/* Minification failed. Returning unminified contents.
(362,35-36): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: b
(362,28-29): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: g
(362,21-22): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: r
(363,35-36): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: b
(363,28-29): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: g
(363,21-22): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: r
(364,36-37): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: b
(364,29-30): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: g
(364,21-22): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: r
(365,36-37): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: b
(365,29-30): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: g
(365,21-22): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: r
(366,36-37): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: b
(366,28-29): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: g
(366,21-22): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: r
(367,36-37): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: b
(367,28-29): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: g
(367,21-22): run-time error JS1300: Strict-mode does not allow assignment to undefined variables: r
 */
/*!
 * Chart.js v2.8.0
 * https://www.chartjs.org
 * (c) 2019 Chart.js Contributors
 * Released under the MIT License
 */
(function (global, factory) {
    typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory(function () { try { return require('moment'); } catch (e) { } }()) :
        typeof define === 'function' && define.amd ? define(['require'], function (require) { return factory(function () { try { return require('moment'); } catch (e) { } }()); }) :
            (global.Chart = factory(global.moment));
}(this, (function (moment) {
    'use strict';

    moment = moment && moment.hasOwnProperty('default') ? moment['default'] : moment;

    /* MIT license */

    var conversions = {
        rgb2hsl: rgb2hsl,
        rgb2hsv: rgb2hsv,
        rgb2hwb: rgb2hwb,
        rgb2cmyk: rgb2cmyk,
        rgb2keyword: rgb2keyword,
        rgb2xyz: rgb2xyz,
        rgb2lab: rgb2lab,
        rgb2lch: rgb2lch,

        hsl2rgb: hsl2rgb,
        hsl2hsv: hsl2hsv,
        hsl2hwb: hsl2hwb,
        hsl2cmyk: hsl2cmyk,
        hsl2keyword: hsl2keyword,

        hsv2rgb: hsv2rgb,
        hsv2hsl: hsv2hsl,
        hsv2hwb: hsv2hwb,
        hsv2cmyk: hsv2cmyk,
        hsv2keyword: hsv2keyword,

        hwb2rgb: hwb2rgb,
        hwb2hsl: hwb2hsl,
        hwb2hsv: hwb2hsv,
        hwb2cmyk: hwb2cmyk,
        hwb2keyword: hwb2keyword,

        cmyk2rgb: cmyk2rgb,
        cmyk2hsl: cmyk2hsl,
        cmyk2hsv: cmyk2hsv,
        cmyk2hwb: cmyk2hwb,
        cmyk2keyword: cmyk2keyword,

        keyword2rgb: keyword2rgb,
        keyword2hsl: keyword2hsl,
        keyword2hsv: keyword2hsv,
        keyword2hwb: keyword2hwb,
        keyword2cmyk: keyword2cmyk,
        keyword2lab: keyword2lab,
        keyword2xyz: keyword2xyz,

        xyz2rgb: xyz2rgb,
        xyz2lab: xyz2lab,
        xyz2lch: xyz2lch,

        lab2xyz: lab2xyz,
        lab2rgb: lab2rgb,
        lab2lch: lab2lch,

        lch2lab: lch2lab,
        lch2xyz: lch2xyz,
        lch2rgb: lch2rgb
    };


    function rgb2hsl(rgb) {
        var r = rgb[0] / 255,
            g = rgb[1] / 255,
            b = rgb[2] / 255,
            min = Math.min(r, g, b),
            max = Math.max(r, g, b),
            delta = max - min,
            h, s, l;

        if (max == min)
            h = 0;
        else if (r == max)
            h = (g - b) / delta;
        else if (g == max)
            h = 2 + (b - r) / delta;
        else if (b == max)
            h = 4 + (r - g) / delta;

        h = Math.min(h * 60, 360);

        if (h < 0)
            h += 360;

        l = (min + max) / 2;

        if (max == min)
            s = 0;
        else if (l <= 0.5)
            s = delta / (max + min);
        else
            s = delta / (2 - max - min);

        return [h, s * 100, l * 100];
    }

    function rgb2hsv(rgb) {
        var r = rgb[0],
            g = rgb[1],
            b = rgb[2],
            min = Math.min(r, g, b),
            max = Math.max(r, g, b),
            delta = max - min,
            h, s, v;

        if (max == 0)
            s = 0;
        else
            s = (delta / max * 1000) / 10;

        if (max == min)
            h = 0;
        else if (r == max)
            h = (g - b) / delta;
        else if (g == max)
            h = 2 + (b - r) / delta;
        else if (b == max)
            h = 4 + (r - g) / delta;

        h = Math.min(h * 60, 360);

        if (h < 0)
            h += 360;

        v = ((max / 255) * 1000) / 10;

        return [h, s, v];
    }

    function rgb2hwb(rgb) {
        var r = rgb[0],
            g = rgb[1],
            b = rgb[2],
            h = rgb2hsl(rgb)[0],
            w = 1 / 255 * Math.min(r, Math.min(g, b)),
            b = 1 - 1 / 255 * Math.max(r, Math.max(g, b));

        return [h, w * 100, b * 100];
    }

    function rgb2cmyk(rgb) {
        var r = rgb[0] / 255,
            g = rgb[1] / 255,
            b = rgb[2] / 255,
            c, m, y, k;

        k = Math.min(1 - r, 1 - g, 1 - b);
        c = (1 - r - k) / (1 - k) || 0;
        m = (1 - g - k) / (1 - k) || 0;
        y = (1 - b - k) / (1 - k) || 0;
        return [c * 100, m * 100, y * 100, k * 100];
    }

    function rgb2keyword(rgb) {
        return reverseKeywords[JSON.stringify(rgb)];
    }

    function rgb2xyz(rgb) {
        var r = rgb[0] / 255,
            g = rgb[1] / 255,
            b = rgb[2] / 255;

        // assume sRGB
        r = r > 0.04045 ? Math.pow(((r + 0.055) / 1.055), 2.4) : (r / 12.92);
        g = g > 0.04045 ? Math.pow(((g + 0.055) / 1.055), 2.4) : (g / 12.92);
        b = b > 0.04045 ? Math.pow(((b + 0.055) / 1.055), 2.4) : (b / 12.92);

        var x = (r * 0.4124) + (g * 0.3576) + (b * 0.1805);
        var y = (r * 0.2126) + (g * 0.7152) + (b * 0.0722);
        var z = (r * 0.0193) + (g * 0.1192) + (b * 0.9505);

        return [x * 100, y * 100, z * 100];
    }

    function rgb2lab(rgb) {
        var xyz = rgb2xyz(rgb),
            x = xyz[0],
            y = xyz[1],
            z = xyz[2],
            l, a, b;

        x /= 95.047;
        y /= 100;
        z /= 108.883;

        x = x > 0.008856 ? Math.pow(x, 1 / 3) : (7.787 * x) + (16 / 116);
        y = y > 0.008856 ? Math.pow(y, 1 / 3) : (7.787 * y) + (16 / 116);
        z = z > 0.008856 ? Math.pow(z, 1 / 3) : (7.787 * z) + (16 / 116);

        l = (116 * y) - 16;
        a = 500 * (x - y);
        b = 200 * (y - z);

        return [l, a, b];
    }

    function rgb2lch(args) {
        return lab2lch(rgb2lab(args));
    }

    function hsl2rgb(hsl) {
        var h = hsl[0] / 360,
            s = hsl[1] / 100,
            l = hsl[2] / 100,
            t1, t2, t3, rgb, val;

        if (s == 0) {
            val = l * 255;
            return [val, val, val];
        }

        if (l < 0.5)
            t2 = l * (1 + s);
        else
            t2 = l + s - l * s;
        t1 = 2 * l - t2;

        rgb = [0, 0, 0];
        for (var i = 0; i < 3; i++) {
            t3 = h + 1 / 3 * - (i - 1);
            t3 < 0 && t3++;
            t3 > 1 && t3--;

            if (6 * t3 < 1)
                val = t1 + (t2 - t1) * 6 * t3;
            else if (2 * t3 < 1)
                val = t2;
            else if (3 * t3 < 2)
                val = t1 + (t2 - t1) * (2 / 3 - t3) * 6;
            else
                val = t1;

            rgb[i] = val * 255;
        }

        return rgb;
    }

    function hsl2hsv(hsl) {
        var h = hsl[0],
            s = hsl[1] / 100,
            l = hsl[2] / 100,
            sv, v;

        if (l === 0) {
            // no need to do calc on black
            // also avoids divide by 0 error
            return [0, 0, 0];
        }

        l *= 2;
        s *= (l <= 1) ? l : 2 - l;
        v = (l + s) / 2;
        sv = (2 * s) / (l + s);
        return [h, sv * 100, v * 100];
    }

    function hsl2hwb(args) {
        return rgb2hwb(hsl2rgb(args));
    }

    function hsl2cmyk(args) {
        return rgb2cmyk(hsl2rgb(args));
    }

    function hsl2keyword(args) {
        return rgb2keyword(hsl2rgb(args));
    }


    function hsv2rgb(hsv) {
        var h = hsv[0] / 60,
            s = hsv[1] / 100,
            v = hsv[2] / 100,
            hi = Math.floor(h) % 6;

        var f = h - Math.floor(h),
            p = 255 * v * (1 - s),
            q = 255 * v * (1 - (s * f)),
            t = 255 * v * (1 - (s * (1 - f))),
            v = 255 * v;

        switch (hi) {
            case 0:
                return [v, t, p];
            case 1:
                return [q, v, p];
            case 2:
                return [p, v, t];
            case 3:
                return [p, q, v];
            case 4:
                return [t, p, v];
            case 5:
                return [v, p, q];
        }
    }

    function hsv2hsl(hsv) {
        var h = hsv[0],
            s = hsv[1] / 100,
            v = hsv[2] / 100,
            sl, l;

        l = (2 - s) * v;
        sl = s * v;
        sl /= (l <= 1) ? l : 2 - l;
        sl = sl || 0;
        l /= 2;
        return [h, sl * 100, l * 100];
    }

    function hsv2hwb(args) {
        return rgb2hwb(hsv2rgb(args))
    }

    function hsv2cmyk(args) {
        return rgb2cmyk(hsv2rgb(args));
    }

    function hsv2keyword(args) {
        return rgb2keyword(hsv2rgb(args));
    }

    // http://dev.w3.org/csswg/css-color/#hwb-to-rgb
    function hwb2rgb(hwb) {
        var h = hwb[0] / 360,
            wh = hwb[1] / 100,
            bl = hwb[2] / 100,
            ratio = wh + bl,
            i, v, f, n;

        // wh + bl cant be > 1
        if (ratio > 1) {
            wh /= ratio;
            bl /= ratio;
        }

        i = Math.floor(6 * h);
        v = 1 - bl;
        f = 6 * h - i;
        if ((i & 0x01) != 0) {
            f = 1 - f;
        }
        n = wh + f * (v - wh);  // linear interpolation

        switch (i) {
            default:
            case 6:
            case 0: r = v; g = n; b = wh; break;
            case 1: r = n; g = v; b = wh; break;
            case 2: r = wh; g = v; b = n; break;
            case 3: r = wh; g = n; b = v; break;
            case 4: r = n; g = wh; b = v; break;
            case 5: r = v; g = wh; b = n; break;
        }

        return [r * 255, g * 255, b * 255];
    }

    function hwb2hsl(args) {
        return rgb2hsl(hwb2rgb(args));
    }

    function hwb2hsv(args) {
        return rgb2hsv(hwb2rgb(args));
    }

    function hwb2cmyk(args) {
        return rgb2cmyk(hwb2rgb(args));
    }

    function hwb2keyword(args) {
        return rgb2keyword(hwb2rgb(args));
    }

    function cmyk2rgb(cmyk) {
        var c = cmyk[0] / 100,
            m = cmyk[1] / 100,
            y = cmyk[2] / 100,
            k = cmyk[3] / 100,
            r, g, b;

        r = 1 - Math.min(1, c * (1 - k) + k);
        g = 1 - Math.min(1, m * (1 - k) + k);
        b = 1 - Math.min(1, y * (1 - k) + k);
        return [r * 255, g * 255, b * 255];
    }

    function cmyk2hsl(args) {
        return rgb2hsl(cmyk2rgb(args));
    }

    function cmyk2hsv(args) {
        return rgb2hsv(cmyk2rgb(args));
    }

    function cmyk2hwb(args) {
        return rgb2hwb(cmyk2rgb(args));
    }

    function cmyk2keyword(args) {
        return rgb2keyword(cmyk2rgb(args));
    }


    function xyz2rgb(xyz) {
        var x = xyz[0] / 100,
            y = xyz[1] / 100,
            z = xyz[2] / 100,
            r, g, b;

        r = (x * 3.2406) + (y * -1.5372) + (z * -0.4986);
        g = (x * -0.9689) + (y * 1.8758) + (z * 0.0415);
        b = (x * 0.0557) + (y * -0.2040) + (z * 1.0570);

        // assume sRGB
        r = r > 0.0031308 ? ((1.055 * Math.pow(r, 1.0 / 2.4)) - 0.055)
            : r = (r * 12.92);

        g = g > 0.0031308 ? ((1.055 * Math.pow(g, 1.0 / 2.4)) - 0.055)
            : g = (g * 12.92);

        b = b > 0.0031308 ? ((1.055 * Math.pow(b, 1.0 / 2.4)) - 0.055)
            : b = (b * 12.92);

        r = Math.min(Math.max(0, r), 1);
        g = Math.min(Math.max(0, g), 1);
        b = Math.min(Math.max(0, b), 1);

        return [r * 255, g * 255, b * 255];
    }

    function xyz2lab(xyz) {
        var x = xyz[0],
            y = xyz[1],
            z = xyz[2],
            l, a, b;

        x /= 95.047;
        y /= 100;
        z /= 108.883;

        x = x > 0.008856 ? Math.pow(x, 1 / 3) : (7.787 * x) + (16 / 116);
        y = y > 0.008856 ? Math.pow(y, 1 / 3) : (7.787 * y) + (16 / 116);
        z = z > 0.008856 ? Math.pow(z, 1 / 3) : (7.787 * z) + (16 / 116);

        l = (116 * y) - 16;
        a = 500 * (x - y);
        b = 200 * (y - z);

        return [l, a, b];
    }

    function xyz2lch(args) {
        return lab2lch(xyz2lab(args));
    }

    function lab2xyz(lab) {
        var l = lab[0],
            a = lab[1],
            b = lab[2],
            x, y, z, y2;

        if (l <= 8) {
            y = (l * 100) / 903.3;
            y2 = (7.787 * (y / 100)) + (16 / 116);
        } else {
            y = 100 * Math.pow((l + 16) / 116, 3);
            y2 = Math.pow(y / 100, 1 / 3);
        }

        x = x / 95.047 <= 0.008856 ? x = (95.047 * ((a / 500) + y2 - (16 / 116))) / 7.787 : 95.047 * Math.pow((a / 500) + y2, 3);

        z = z / 108.883 <= 0.008859 ? z = (108.883 * (y2 - (b / 200) - (16 / 116))) / 7.787 : 108.883 * Math.pow(y2 - (b / 200), 3);

        return [x, y, z];
    }

    function lab2lch(lab) {
        var l = lab[0],
            a = lab[1],
            b = lab[2],
            hr, h, c;

        hr = Math.atan2(b, a);
        h = hr * 360 / 2 / Math.PI;
        if (h < 0) {
            h += 360;
        }
        c = Math.sqrt(a * a + b * b);
        return [l, c, h];
    }

    function lab2rgb(args) {
        return xyz2rgb(lab2xyz(args));
    }

    function lch2lab(lch) {
        var l = lch[0],
            c = lch[1],
            h = lch[2],
            a, b, hr;

        hr = h / 360 * 2 * Math.PI;
        a = c * Math.cos(hr);
        b = c * Math.sin(hr);
        return [l, a, b];
    }

    function lch2xyz(args) {
        return lab2xyz(lch2lab(args));
    }

    function lch2rgb(args) {
        return lab2rgb(lch2lab(args));
    }

    function keyword2rgb(keyword) {
        return cssKeywords[keyword];
    }

    function keyword2hsl(args) {
        return rgb2hsl(keyword2rgb(args));
    }

    function keyword2hsv(args) {
        return rgb2hsv(keyword2rgb(args));
    }

    function keyword2hwb(args) {
        return rgb2hwb(keyword2rgb(args));
    }

    function keyword2cmyk(args) {
        return rgb2cmyk(keyword2rgb(args));
    }

    function keyword2lab(args) {
        return rgb2lab(keyword2rgb(args));
    }

    function keyword2xyz(args) {
        return rgb2xyz(keyword2rgb(args));
    }

    var cssKeywords = {
        aliceblue: [240, 248, 255],
        antiquewhite: [250, 235, 215],
        aqua: [0, 255, 255],
        aquamarine: [127, 255, 212],
        azure: [240, 255, 255],
        beige: [245, 245, 220],
        bisque: [255, 228, 196],
        black: [0, 0, 0],
        blanchedalmond: [255, 235, 205],
        blue: [0, 0, 255],
        blueviolet: [138, 43, 226],
        brown: [165, 42, 42],
        burlywood: [222, 184, 135],
        cadetblue: [95, 158, 160],
        chartreuse: [127, 255, 0],
        chocolate: [210, 105, 30],
        coral: [255, 127, 80],
        cornflowerblue: [100, 149, 237],
        cornsilk: [255, 248, 220],
        crimson: [220, 20, 60],
        cyan: [0, 255, 255],
        darkblue: [0, 0, 139],
        darkcyan: [0, 139, 139],
        darkgoldenrod: [184, 134, 11],
        darkgray: [169, 169, 169],
        darkgreen: [0, 100, 0],
        darkgrey: [169, 169, 169],
        darkkhaki: [189, 183, 107],
        darkmagenta: [139, 0, 139],
        darkolivegreen: [85, 107, 47],
        darkorange: [255, 140, 0],
        darkorchid: [153, 50, 204],
        darkred: [139, 0, 0],
        darksalmon: [233, 150, 122],
        darkseagreen: [143, 188, 143],
        darkslateblue: [72, 61, 139],
        darkslategray: [47, 79, 79],
        darkslategrey: [47, 79, 79],
        darkturquoise: [0, 206, 209],
        darkviolet: [148, 0, 211],
        deeppink: [255, 20, 147],
        deepskyblue: [0, 191, 255],
        dimgray: [105, 105, 105],
        dimgrey: [105, 105, 105],
        dodgerblue: [30, 144, 255],
        firebrick: [178, 34, 34],
        floralwhite: [255, 250, 240],
        forestgreen: [34, 139, 34],
        fuchsia: [255, 0, 255],
        gainsboro: [220, 220, 220],
        ghostwhite: [248, 248, 255],
        gold: [255, 215, 0],
        goldenrod: [218, 165, 32],
        gray: [128, 128, 128],
        green: [0, 128, 0],
        greenyellow: [173, 255, 47],
        grey: [128, 128, 128],
        honeydew: [240, 255, 240],
        hotpink: [255, 105, 180],
        indianred: [205, 92, 92],
        indigo: [75, 0, 130],
        ivory: [255, 255, 240],
        khaki: [240, 230, 140],
        lavender: [230, 230, 250],
        lavenderblush: [255, 240, 245],
        lawngreen: [124, 252, 0],
        lemonchiffon: [255, 250, 205],
        lightblue: [173, 216, 230],
        lightcoral: [240, 128, 128],
        lightcyan: [224, 255, 255],
        lightgoldenrodyellow: [250, 250, 210],
        lightgray: [211, 211, 211],
        lightgreen: [144, 238, 144],
        lightgrey: [211, 211, 211],
        lightpink: [255, 182, 193],
        lightsalmon: [255, 160, 122],
        lightseagreen: [32, 178, 170],
        lightskyblue: [135, 206, 250],
        lightslategray: [119, 136, 153],
        lightslategrey: [119, 136, 153],
        lightsteelblue: [176, 196, 222],
        lightyellow: [255, 255, 224],
        lime: [0, 255, 0],
        limegreen: [50, 205, 50],
        linen: [250, 240, 230],
        magenta: [255, 0, 255],
        maroon: [128, 0, 0],
        mediumaquamarine: [102, 205, 170],
        mediumblue: [0, 0, 205],
        mediumorchid: [186, 85, 211],
        mediumpurple: [147, 112, 219],
        mediumseagreen: [60, 179, 113],
        mediumslateblue: [123, 104, 238],
        mediumspringgreen: [0, 250, 154],
        mediumturquoise: [72, 209, 204],
        mediumvioletred: [199, 21, 133],
        midnightblue: [25, 25, 112],
        mintcream: [245, 255, 250],
        mistyrose: [255, 228, 225],
        moccasin: [255, 228, 181],
        navajowhite: [255, 222, 173],
        navy: [0, 0, 128],
        oldlace: [253, 245, 230],
        olive: [128, 128, 0],
        olivedrab: [107, 142, 35],
        orange: [255, 165, 0],
        orangered: [255, 69, 0],
        orchid: [218, 112, 214],
        palegoldenrod: [238, 232, 170],
        palegreen: [152, 251, 152],
        paleturquoise: [175, 238, 238],
        palevioletred: [219, 112, 147],
        papayawhip: [255, 239, 213],
        peachpuff: [255, 218, 185],
        peru: [205, 133, 63],
        pink: [255, 192, 203],
        plum: [221, 160, 221],
        powderblue: [176, 224, 230],
        purple: [128, 0, 128],
        rebeccapurple: [102, 51, 153],
        red: [255, 0, 0],
        rosybrown: [188, 143, 143],
        royalblue: [65, 105, 225],
        saddlebrown: [139, 69, 19],
        salmon: [250, 128, 114],
        sandybrown: [244, 164, 96],
        seagreen: [46, 139, 87],
        seashell: [255, 245, 238],
        sienna: [160, 82, 45],
        silver: [192, 192, 192],
        skyblue: [135, 206, 235],
        slateblue: [106, 90, 205],
        slategray: [112, 128, 144],
        slategrey: [112, 128, 144],
        snow: [255, 250, 250],
        springgreen: [0, 255, 127],
        steelblue: [70, 130, 180],
        tan: [210, 180, 140],
        teal: [0, 128, 128],
        thistle: [216, 191, 216],
        tomato: [255, 99, 71],
        turquoise: [64, 224, 208],
        violet: [238, 130, 238],
        wheat: [245, 222, 179],
        white: [255, 255, 255],
        whitesmoke: [245, 245, 245],
        yellow: [255, 255, 0],
        yellowgreen: [154, 205, 50]
    };

    var reverseKeywords = {};
    for (var key in cssKeywords) {
        reverseKeywords[JSON.stringify(cssKeywords[key])] = key;
    }

    var convert = function () {
        return new Converter();
    };

    for (var func in conversions) {
        // export Raw versions
        convert[func + "Raw"] = (function (func) {
            // accept array or plain args
            return function (arg) {
                if (typeof arg == "number")
                    arg = Array.prototype.slice.call(arguments);
                return conversions[func](arg);
            }
        })(func);

        var pair = /(\w+)2(\w+)/.exec(func),
            from = pair[1],
            to = pair[2];

        // export rgb2hsl and ["rgb"]["hsl"]
        convert[from] = convert[from] || {};

        convert[from][to] = convert[func] = (function (func) {
            return function (arg) {
                if (typeof arg == "number")
                    arg = Array.prototype.slice.call(arguments);

                var val = conversions[func](arg);
                if (typeof val == "string" || val === undefined)
                    return val; // keyword

                for (var i = 0; i < val.length; i++)
                    val[i] = Math.round(val[i]);
                return val;
            }
        })(func);
    }


    /* Converter does lazy conversion and caching */
    var Converter = function () {
        this.convs = {};
    };

    /* Either get the values for a space or
      set the values for a space, depending on args */
    Converter.prototype.routeSpace = function (space, args) {
        var values = args[0];
        if (values === undefined) {
            // color.rgb()
            return this.getValues(space);
        }
        // color.rgb(10, 10, 10)
        if (typeof values == "number") {
            values = Array.prototype.slice.call(args);
        }

        return this.setValues(space, values);
    };

    /* Set the values for a space, invalidating cache */
    Converter.prototype.setValues = function (space, values) {
        this.space = space;
        this.convs = {};
        this.convs[space] = values;
        return this;
    };

    /* Get the values for a space. If there's already
      a conversion for the space, fetch it, otherwise
      compute it */
    Converter.prototype.getValues = function (space) {
        var vals = this.convs[space];
        if (!vals) {
            var fspace = this.space,
                from = this.convs[fspace];
            vals = convert[fspace][space](from);

            this.convs[space] = vals;
        }
        return vals;
    };

    ["rgb", "hsl", "hsv", "cmyk", "keyword"].forEach(function (space) {
        Converter.prototype[space] = function (vals) {
            return this.routeSpace(space, arguments);
        };
    });

    var colorConvert = convert;

    var colorName = {
        "aliceblue": [240, 248, 255],
        "antiquewhite": [250, 235, 215],
        "aqua": [0, 255, 255],
        "aquamarine": [127, 255, 212],
        "azure": [240, 255, 255],
        "beige": [245, 245, 220],
        "bisque": [255, 228, 196],
        "black": [0, 0, 0],
        "blanchedalmond": [255, 235, 205],
        "blue": [0, 0, 255],
        "blueviolet": [138, 43, 226],
        "brown": [165, 42, 42],
        "burlywood": [222, 184, 135],
        "cadetblue": [95, 158, 160],
        "chartreuse": [127, 255, 0],
        "chocolate": [210, 105, 30],
        "coral": [255, 127, 80],
        "cornflowerblue": [100, 149, 237],
        "cornsilk": [255, 248, 220],
        "crimson": [220, 20, 60],
        "cyan": [0, 255, 255],
        "darkblue": [0, 0, 139],
        "darkcyan": [0, 139, 139],
        "darkgoldenrod": [184, 134, 11],
        "darkgray": [169, 169, 169],
        "darkgreen": [0, 100, 0],
        "darkgrey": [169, 169, 169],
        "darkkhaki": [189, 183, 107],
        "darkmagenta": [139, 0, 139],
        "darkolivegreen": [85, 107, 47],
        "darkorange": [255, 140, 0],
        "darkorchid": [153, 50, 204],
        "darkred": [139, 0, 0],
        "darksalmon": [233, 150, 122],
        "darkseagreen": [143, 188, 143],
        "darkslateblue": [72, 61, 139],
        "darkslategray": [47, 79, 79],
        "darkslategrey": [47, 79, 79],
        "darkturquoise": [0, 206, 209],
        "darkviolet": [148, 0, 211],
        "deeppink": [255, 20, 147],
        "deepskyblue": [0, 191, 255],
        "dimgray": [105, 105, 105],
        "dimgrey": [105, 105, 105],
        "dodgerblue": [30, 144, 255],
        "firebrick": [178, 34, 34],
        "floralwhite": [255, 250, 240],
        "forestgreen": [34, 139, 34],
        "fuchsia": [255, 0, 255],
        "gainsboro": [220, 220, 220],
        "ghostwhite": [248, 248, 255],
        "gold": [255, 215, 0],
        "goldenrod": [218, 165, 32],
        "gray": [128, 128, 128],
        "green": [0, 128, 0],
        "greenyellow": [173, 255, 47],
        "grey": [128, 128, 128],
        "honeydew": [240, 255, 240],
        "hotpink": [255, 105, 180],
        "indianred": [205, 92, 92],
        "indigo": [75, 0, 130],
        "ivory": [255, 255, 240],
        "khaki": [240, 230, 140],
        "lavender": [230, 230, 250],
        "lavenderblush": [255, 240, 245],
        "lawngreen": [124, 252, 0],
        "lemonchiffon": [255, 250, 205],
        "lightblue": [173, 216, 230],
        "lightcoral": [240, 128, 128],
        "lightcyan": [224, 255, 255],
        "lightgoldenrodyellow": [250, 250, 210],
        "lightgray": [211, 211, 211],
        "lightgreen": [144, 238, 144],
        "lightgrey": [211, 211, 211],
        "lightpink": [255, 182, 193],
        "lightsalmon": [255, 160, 122],
        "lightseagreen": [32, 178, 170],
        "lightskyblue": [135, 206, 250],
        "lightslategray": [119, 136, 153],
        "lightslategrey": [119, 136, 153],
        "lightsteelblue": [176, 196, 222],
        "lightyellow": [255, 255, 224],
        "lime": [0, 255, 0],
        "limegreen": [50, 205, 50],
        "linen": [250, 240, 230],
        "magenta": [255, 0, 255],
        "maroon": [128, 0, 0],
        "mediumaquamarine": [102, 205, 170],
        "mediumblue": [0, 0, 205],
        "mediumorchid": [186, 85, 211],
        "mediumpurple": [147, 112, 219],
        "mediumseagreen": [60, 179, 113],
        "mediumslateblue": [123, 104, 238],
        "mediumspringgreen": [0, 250, 154],
        "mediumturquoise": [72, 209, 204],
        "mediumvioletred": [199, 21, 133],
        "midnightblue": [25, 25, 112],
        "mintcream": [245, 255, 250],
        "mistyrose": [255, 228, 225],
        "moccasin": [255, 228, 181],
        "navajowhite": [255, 222, 173],
        "navy": [0, 0, 128],
        "oldlace": [253, 245, 230],
        "olive": [128, 128, 0],
        "olivedrab": [107, 142, 35],
        "orange": [255, 165, 0],
        "orangered": [255, 69, 0],
        "orchid": [218, 112, 214],
        "palegoldenrod": [238, 232, 170],
        "palegreen": [152, 251, 152],
        "paleturquoise": [175, 238, 238],
        "palevioletred": [219, 112, 147],
        "papayawhip": [255, 239, 213],
        "peachpuff": [255, 218, 185],
        "peru": [205, 133, 63],
        "pink": [255, 192, 203],
        "plum": [221, 160, 221],
        "powderblue": [176, 224, 230],
        "purple": [128, 0, 128],
        "rebeccapurple": [102, 51, 153],
        "red": [255, 0, 0],
        "rosybrown": [188, 143, 143],
        "royalblue": [65, 105, 225],
        "saddlebrown": [139, 69, 19],
        "salmon": [250, 128, 114],
        "sandybrown": [244, 164, 96],
        "seagreen": [46, 139, 87],
        "seashell": [255, 245, 238],
        "sienna": [160, 82, 45],
        "silver": [192, 192, 192],
        "skyblue": [135, 206, 235],
        "slateblue": [106, 90, 205],
        "slategray": [112, 128, 144],
        "slategrey": [112, 128, 144],
        "snow": [255, 250, 250],
        "springgreen": [0, 255, 127],
        "steelblue": [70, 130, 180],
        "tan": [210, 180, 140],
        "teal": [0, 128, 128],
        "thistle": [216, 191, 216],
        "tomato": [255, 99, 71],
        "turquoise": [64, 224, 208],
        "violet": [238, 130, 238],
        "wheat": [245, 222, 179],
        "white": [255, 255, 255],
        "whitesmoke": [245, 245, 245],
        "yellow": [255, 255, 0],
        "yellowgreen": [154, 205, 50]
    };

    /* MIT license */


    var colorString = {
        getRgba: getRgba,
        getHsla: getHsla,
        getRgb: getRgb,
        getHsl: getHsl,
        getHwb: getHwb,
        getAlpha: getAlpha,

        hexString: hexString,
        rgbString: rgbString,
        rgbaString: rgbaString,
        percentString: percentString,
        percentaString: percentaString,
        hslString: hslString,
        hslaString: hslaString,
        hwbString: hwbString,
        keyword: keyword
    };

    function getRgba(string) {
        if (!string) {
            return;
        }
        var abbr = /^#([a-fA-F0-9]{3,4})$/i,
            hex = /^#([a-fA-F0-9]{6}([a-fA-F0-9]{2})?)$/i,
            rgba = /^rgba?\(\s*([+-]?\d+)\s*,\s*([+-]?\d+)\s*,\s*([+-]?\d+)\s*(?:,\s*([+-]?[\d\.]+)\s*)?\)$/i,
            per = /^rgba?\(\s*([+-]?[\d\.]+)\%\s*,\s*([+-]?[\d\.]+)\%\s*,\s*([+-]?[\d\.]+)\%\s*(?:,\s*([+-]?[\d\.]+)\s*)?\)$/i,
            keyword = /(\w+)/;

        var rgb = [0, 0, 0],
            a = 1,
            match = string.match(abbr),
            hexAlpha = "";
        if (match) {
            match = match[1];
            hexAlpha = match[3];
            for (var i = 0; i < rgb.length; i++) {
                rgb[i] = parseInt(match[i] + match[i], 16);
            }
            if (hexAlpha) {
                a = Math.round((parseInt(hexAlpha + hexAlpha, 16) / 255) * 100) / 100;
            }
        }
        else if (match = string.match(hex)) {
            hexAlpha = match[2];
            match = match[1];
            for (var i = 0; i < rgb.length; i++) {
                rgb[i] = parseInt(match.slice(i * 2, i * 2 + 2), 16);
            }
            if (hexAlpha) {
                a = Math.round((parseInt(hexAlpha, 16) / 255) * 100) / 100;
            }
        }
        else if (match = string.match(rgba)) {
            for (var i = 0; i < rgb.length; i++) {
                rgb[i] = parseInt(match[i + 1]);
            }
            a = parseFloat(match[4]);
        }
        else if (match = string.match(per)) {
            for (var i = 0; i < rgb.length; i++) {
                rgb[i] = Math.round(parseFloat(match[i + 1]) * 2.55);
            }
            a = parseFloat(match[4]);
        }
        else if (match = string.match(keyword)) {
            if (match[1] == "transparent") {
                return [0, 0, 0, 0];
            }
            rgb = colorName[match[1]];
            if (!rgb) {
                return;
            }
        }

        for (var i = 0; i < rgb.length; i++) {
            rgb[i] = scale(rgb[i], 0, 255);
        }
        if (!a && a != 0) {
            a = 1;
        }
        else {
            a = scale(a, 0, 1);
        }
        rgb[3] = a;
        return rgb;
    }

    function getHsla(string) {
        if (!string) {
            return;
        }
        var hsl = /^hsla?\(\s*([+-]?\d+)(?:deg)?\s*,\s*([+-]?[\d\.]+)%\s*,\s*([+-]?[\d\.]+)%\s*(?:,\s*([+-]?[\d\.]+)\s*)?\)/;
        var match = string.match(hsl);
        if (match) {
            var alpha = parseFloat(match[4]);
            var h = scale(parseInt(match[1]), 0, 360),
                s = scale(parseFloat(match[2]), 0, 100),
                l = scale(parseFloat(match[3]), 0, 100),
                a = scale(isNaN(alpha) ? 1 : alpha, 0, 1);
            return [h, s, l, a];
        }
    }

    function getHwb(string) {
        if (!string) {
            return;
        }
        var hwb = /^hwb\(\s*([+-]?\d+)(?:deg)?\s*,\s*([+-]?[\d\.]+)%\s*,\s*([+-]?[\d\.]+)%\s*(?:,\s*([+-]?[\d\.]+)\s*)?\)/;
        var match = string.match(hwb);
        if (match) {
            var alpha = parseFloat(match[4]);
            var h = scale(parseInt(match[1]), 0, 360),
                w = scale(parseFloat(match[2]), 0, 100),
                b = scale(parseFloat(match[3]), 0, 100),
                a = scale(isNaN(alpha) ? 1 : alpha, 0, 1);
            return [h, w, b, a];
        }
    }

    function getRgb(string) {
        var rgba = getRgba(string);
        return rgba && rgba.slice(0, 3);
    }

    function getHsl(string) {
        var hsla = getHsla(string);
        return hsla && hsla.slice(0, 3);
    }

    function getAlpha(string) {
        var vals = getRgba(string);
        if (vals) {
            return vals[3];
        }
        else if (vals = getHsla(string)) {
            return vals[3];
        }
        else if (vals = getHwb(string)) {
            return vals[3];
        }
    }

    // generators
    function hexString(rgba, a) {
        var a = (a !== undefined && rgba.length === 3) ? a : rgba[3];
        return "#" + hexDouble(rgba[0])
            + hexDouble(rgba[1])
            + hexDouble(rgba[2])
            + (
                (a >= 0 && a < 1)
                    ? hexDouble(Math.round(a * 255))
                    : ""
            );
    }

    function rgbString(rgba, alpha) {
        if (alpha < 1 || (rgba[3] && rgba[3] < 1)) {
            return rgbaString(rgba, alpha);
        }
        return "rgb(" + rgba[0] + ", " + rgba[1] + ", " + rgba[2] + ")";
    }

    function rgbaString(rgba, alpha) {
        if (alpha === undefined) {
            alpha = (rgba[3] !== undefined ? rgba[3] : 1);
        }
        return "rgba(" + rgba[0] + ", " + rgba[1] + ", " + rgba[2]
            + ", " + alpha + ")";
    }

    function percentString(rgba, alpha) {
        if (alpha < 1 || (rgba[3] && rgba[3] < 1)) {
            return percentaString(rgba, alpha);
        }
        var r = Math.round(rgba[0] / 255 * 100),
            g = Math.round(rgba[1] / 255 * 100),
            b = Math.round(rgba[2] / 255 * 100);

        return "rgb(" + r + "%, " + g + "%, " + b + "%)";
    }

    function percentaString(rgba, alpha) {
        var r = Math.round(rgba[0] / 255 * 100),
            g = Math.round(rgba[1] / 255 * 100),
            b = Math.round(rgba[2] / 255 * 100);
        return "rgba(" + r + "%, " + g + "%, " + b + "%, " + (alpha || rgba[3] || 1) + ")";
    }

    function hslString(hsla, alpha) {
        if (alpha < 1 || (hsla[3] && hsla[3] < 1)) {
            return hslaString(hsla, alpha);
        }
        return "hsl(" + hsla[0] + ", " + hsla[1] + "%, " + hsla[2] + "%)";
    }

    function hslaString(hsla, alpha) {
        if (alpha === undefined) {
            alpha = (hsla[3] !== undefined ? hsla[3] : 1);
        }
        return "hsla(" + hsla[0] + ", " + hsla[1] + "%, " + hsla[2] + "%, "
            + alpha + ")";
    }

    // hwb is a bit different than rgb(a) & hsl(a) since there is no alpha specific syntax
    // (hwb have alpha optional & 1 is default value)
    function hwbString(hwb, alpha) {
        if (alpha === undefined) {
            alpha = (hwb[3] !== undefined ? hwb[3] : 1);
        }
        return "hwb(" + hwb[0] + ", " + hwb[1] + "%, " + hwb[2] + "%"
            + (alpha !== undefined && alpha !== 1 ? ", " + alpha : "") + ")";
    }

    function keyword(rgb) {
        return reverseNames[rgb.slice(0, 3)];
    }

    // helpers
    function scale(num, min, max) {
        return Math.min(Math.max(min, num), max);
    }

    function hexDouble(num) {
        var str = num.toString(16).toUpperCase();
        return (str.length < 2) ? "0" + str : str;
    }


    //create a list of reverse color names
    var reverseNames = {};
    for (var name in colorName) {
        reverseNames[colorName[name]] = name;
    }

    /* MIT license */



    var Color = function (obj) {
        if (obj instanceof Color) {
            return obj;
        }
        if (!(this instanceof Color)) {
            return new Color(obj);
        }

        this.valid = false;
        this.values = {
            rgb: [0, 0, 0],
            hsl: [0, 0, 0],
            hsv: [0, 0, 0],
            hwb: [0, 0, 0],
            cmyk: [0, 0, 0, 0],
            alpha: 1
        };

        // parse Color() argument
        var vals;
        if (typeof obj === 'string') {
            vals = colorString.getRgba(obj);
            if (vals) {
                this.setValues('rgb', vals);
            } else if (vals = colorString.getHsla(obj)) {
                this.setValues('hsl', vals);
            } else if (vals = colorString.getHwb(obj)) {
                this.setValues('hwb', vals);
            }
        } else if (typeof obj === 'object') {
            vals = obj;
            if (vals.r !== undefined || vals.red !== undefined) {
                this.setValues('rgb', vals);
            } else if (vals.l !== undefined || vals.lightness !== undefined) {
                this.setValues('hsl', vals);
            } else if (vals.v !== undefined || vals.value !== undefined) {
                this.setValues('hsv', vals);
            } else if (vals.w !== undefined || vals.whiteness !== undefined) {
                this.setValues('hwb', vals);
            } else if (vals.c !== undefined || vals.cyan !== undefined) {
                this.setValues('cmyk', vals);
            }
        }
    };

    Color.prototype = {
        isValid: function () {
            return this.valid;
        },
        rgb: function () {
            return this.setSpace('rgb', arguments);
        },
        hsl: function () {
            return this.setSpace('hsl', arguments);
        },
        hsv: function () {
            return this.setSpace('hsv', arguments);
        },
        hwb: function () {
            return this.setSpace('hwb', arguments);
        },
        cmyk: function () {
            return this.setSpace('cmyk', arguments);
        },

        rgbArray: function () {
            return this.values.rgb;
        },
        hslArray: function () {
            return this.values.hsl;
        },
        hsvArray: function () {
            return this.values.hsv;
        },
        hwbArray: function () {
            var values = this.values;
            if (values.alpha !== 1) {
                return values.hwb.concat([values.alpha]);
            }
            return values.hwb;
        },
        cmykArray: function () {
            return this.values.cmyk;
        },
        rgbaArray: function () {
            var values = this.values;
            return values.rgb.concat([values.alpha]);
        },
        hslaArray: function () {
            var values = this.values;
            return values.hsl.concat([values.alpha]);
        },
        alpha: function (val) {
            if (val === undefined) {
                return this.values.alpha;
            }
            this.setValues('alpha', val);
            return this;
        },

        red: function (val) {
            return this.setChannel('rgb', 0, val);
        },
        green: function (val) {
            return this.setChannel('rgb', 1, val);
        },
        blue: function (val) {
            return this.setChannel('rgb', 2, val);
        },
        hue: function (val) {
            if (val) {
                val %= 360;
                val = val < 0 ? 360 + val : val;
            }
            return this.setChannel('hsl', 0, val);
        },
        saturation: function (val) {
            return this.setChannel('hsl', 1, val);
        },
        lightness: function (val) {
            return this.setChannel('hsl', 2, val);
        },
        saturationv: function (val) {
            return this.setChannel('hsv', 1, val);
        },
        whiteness: function (val) {
            return this.setChannel('hwb', 1, val);
        },
        blackness: function (val) {
            return this.setChannel('hwb', 2, val);
        },
        value: function (val) {
            return this.setChannel('hsv', 2, val);
        },
        cyan: function (val) {
            return this.setChannel('cmyk', 0, val);
        },
        magenta: function (val) {
            return this.setChannel('cmyk', 1, val);
        },
        yellow: function (val) {
            return this.setChannel('cmyk', 2, val);
        },
        black: function (val) {
            return this.setChannel('cmyk', 3, val);
        },

        hexString: function () {
            return colorString.hexString(this.values.rgb);
        },
        rgbString: function () {
            return colorString.rgbString(this.values.rgb, this.values.alpha);
        },
        rgbaString: function () {
            return colorString.rgbaString(this.values.rgb, this.values.alpha);
        },
        percentString: function () {
            return colorString.percentString(this.values.rgb, this.values.alpha);
        },
        hslString: function () {
            return colorString.hslString(this.values.hsl, this.values.alpha);
        },
        hslaString: function () {
            return colorString.hslaString(this.values.hsl, this.values.alpha);
        },
        hwbString: function () {
            return colorString.hwbString(this.values.hwb, this.values.alpha);
        },
        keyword: function () {
            return colorString.keyword(this.values.rgb, this.values.alpha);
        },

        rgbNumber: function () {
            var rgb = this.values.rgb;
            return (rgb[0] << 16) | (rgb[1] << 8) | rgb[2];
        },

        luminosity: function () {
            // http://www.w3.org/TR/WCAG20/#relativeluminancedef
            var rgb = this.values.rgb;
            var lum = [];
            for (var i = 0; i < rgb.length; i++) {
                var chan = rgb[i] / 255;
                lum[i] = (chan <= 0.03928) ? chan / 12.92 : Math.pow(((chan + 0.055) / 1.055), 2.4);
            }
            return 0.2126 * lum[0] + 0.7152 * lum[1] + 0.0722 * lum[2];
        },

        contrast: function (color2) {
            // http://www.w3.org/TR/WCAG20/#contrast-ratiodef
            var lum1 = this.luminosity();
            var lum2 = color2.luminosity();
            if (lum1 > lum2) {
                return (lum1 + 0.05) / (lum2 + 0.05);
            }
            return (lum2 + 0.05) / (lum1 + 0.05);
        },

        level: function (color2) {
            var contrastRatio = this.contrast(color2);
            if (contrastRatio >= 7.1) {
                return 'AAA';
            }

            return (contrastRatio >= 4.5) ? 'AA' : '';
        },

        dark: function () {
            // YIQ equation from http://24ways.org/2010/calculating-color-contrast
            var rgb = this.values.rgb;
            var yiq = (rgb[0] * 299 + rgb[1] * 587 + rgb[2] * 114) / 1000;
            return yiq < 128;
        },

        light: function () {
            return !this.dark();
        },

        negate: function () {
            var rgb = [];
            for (var i = 0; i < 3; i++) {
                rgb[i] = 255 - this.values.rgb[i];
            }
            this.setValues('rgb', rgb);
            return this;
        },

        lighten: function (ratio) {
            var hsl = this.values.hsl;
            hsl[2] += hsl[2] * ratio;
            this.setValues('hsl', hsl);
            return this;
        },

        darken: function (ratio) {
            var hsl = this.values.hsl;
            hsl[2] -= hsl[2] * ratio;
            this.setValues('hsl', hsl);
            return this;
        },

        saturate: function (ratio) {
            var hsl = this.values.hsl;
            hsl[1] += hsl[1] * ratio;
            this.setValues('hsl', hsl);
            return this;
        },

        desaturate: function (ratio) {
            var hsl = this.values.hsl;
            hsl[1] -= hsl[1] * ratio;
            this.setValues('hsl', hsl);
            return this;
        },

        whiten: function (ratio) {
            var hwb = this.values.hwb;
            hwb[1] += hwb[1] * ratio;
            this.setValues('hwb', hwb);
            return this;
        },

        blacken: function (ratio) {
            var hwb = this.values.hwb;
            hwb[2] += hwb[2] * ratio;
            this.setValues('hwb', hwb);
            return this;
        },

        greyscale: function () {
            var rgb = this.values.rgb;
            // http://en.wikipedia.org/wiki/Grayscale#Converting_color_to_grayscale
            var val = rgb[0] * 0.3 + rgb[1] * 0.59 + rgb[2] * 0.11;
            this.setValues('rgb', [val, val, val]);
            return this;
        },

        clearer: function (ratio) {
            var alpha = this.values.alpha;
            this.setValues('alpha', alpha - (alpha * ratio));
            return this;
        },

        opaquer: function (ratio) {
            var alpha = this.values.alpha;
            this.setValues('alpha', alpha + (alpha * ratio));
            return this;
        },

        rotate: function (degrees) {
            var hsl = this.values.hsl;
            var hue = (hsl[0] + degrees) % 360;
            hsl[0] = hue < 0 ? 360 + hue : hue;
            this.setValues('hsl', hsl);
            return this;
        },

        /**
         * Ported from sass implementation in C
         * https://github.com/sass/libsass/blob/0e6b4a2850092356aa3ece07c6b249f0221caced/functions.cpp#L209
         */
        mix: function (mixinColor, weight) {
            var color1 = this;
            var color2 = mixinColor;
            var p = weight === undefined ? 0.5 : weight;

            var w = 2 * p - 1;
            var a = color1.alpha() - color2.alpha();

            var w1 = (((w * a === -1) ? w : (w + a) / (1 + w * a)) + 1) / 2.0;
            var w2 = 1 - w1;

            return this
                .rgb(
                    w1 * color1.red() + w2 * color2.red(),
                    w1 * color1.green() + w2 * color2.green(),
                    w1 * color1.blue() + w2 * color2.blue()
                )
                .alpha(color1.alpha() * p + color2.alpha() * (1 - p));
        },

        toJSON: function () {
            return this.rgb();
        },

        clone: function () {
            // NOTE(SB): using node-clone creates a dependency to Buffer when using browserify,
            // making the final build way to big to embed in Chart.js. So let's do it manually,
            // assuming that values to clone are 1 dimension arrays containing only numbers,
            // except 'alpha' which is a number.
            var result = new Color();
            var source = this.values;
            var target = result.values;
            var value, type;

            for (var prop in source) {
                if (source.hasOwnProperty(prop)) {
                    value = source[prop];
                    type = ({}).toString.call(value);
                    if (type === '[object Array]') {
                        target[prop] = value.slice(0);
                    } else if (type === '[object Number]') {
                        target[prop] = value;
                    } else {
                        console.error('unexpected color value:', value);
                    }
                }
            }

            return result;
        }
    };

    Color.prototype.spaces = {
        rgb: ['red', 'green', 'blue'],
        hsl: ['hue', 'saturation', 'lightness'],
        hsv: ['hue', 'saturation', 'value'],
        hwb: ['hue', 'whiteness', 'blackness'],
        cmyk: ['cyan', 'magenta', 'yellow', 'black']
    };

    Color.prototype.maxes = {
        rgb: [255, 255, 255],
        hsl: [360, 100, 100],
        hsv: [360, 100, 100],
        hwb: [360, 100, 100],
        cmyk: [100, 100, 100, 100]
    };

    Color.prototype.getValues = function (space) {
        var values = this.values;
        var vals = {};

        for (var i = 0; i < space.length; i++) {
            vals[space.charAt(i)] = values[space][i];
        }

        if (values.alpha !== 1) {
            vals.a = values.alpha;
        }

        // {r: 255, g: 255, b: 255, a: 0.4}
        return vals;
    };

    Color.prototype.setValues = function (space, vals) {
        var values = this.values;
        var spaces = this.spaces;
        var maxes = this.maxes;
        var alpha = 1;
        var i;

        this.valid = true;

        if (space === 'alpha') {
            alpha = vals;
        } else if (vals.length) {
            // [10, 10, 10]
            values[space] = vals.slice(0, space.length);
            alpha = vals[space.length];
        } else if (vals[space.charAt(0)] !== undefined) {
            // {r: 10, g: 10, b: 10}
            for (i = 0; i < space.length; i++) {
                values[space][i] = vals[space.charAt(i)];
            }

            alpha = vals.a;
        } else if (vals[spaces[space][0]] !== undefined) {
            // {red: 10, green: 10, blue: 10}
            var chans = spaces[space];

            for (i = 0; i < space.length; i++) {
                values[space][i] = vals[chans[i]];
            }

            alpha = vals.alpha;
        }

        values.alpha = Math.max(0, Math.min(1, (alpha === undefined ? values.alpha : alpha)));

        if (space === 'alpha') {
            return false;
        }

        var capped;

        // cap values of the space prior converting all values
        for (i = 0; i < space.length; i++) {
            capped = Math.max(0, Math.min(maxes[space][i], values[space][i]));
            values[space][i] = Math.round(capped);
        }

        // convert to all the other color spaces
        for (var sname in spaces) {
            if (sname !== space) {
                values[sname] = colorConvert[space][sname](values[space]);
            }
        }

        return true;
    };

    Color.prototype.setSpace = function (space, args) {
        var vals = args[0];

        if (vals === undefined) {
            // color.rgb()
            return this.getValues(space);
        }

        // color.rgb(10, 10, 10)
        if (typeof vals === 'number') {
            vals = Array.prototype.slice.call(args);
        }

        this.setValues(space, vals);
        return this;
    };

    Color.prototype.setChannel = function (space, index, val) {
        var svalues = this.values[space];
        if (val === undefined) {
            // color.red()
            return svalues[index];
        } else if (val === svalues[index]) {
            // color.red(color.red())
            return this;
        }

        // color.red(100)
        svalues[index] = val;
        this.setValues(space, svalues);

        return this;
    };

    if (typeof window !== 'undefined') {
        window.Color = Color;
    }

    var chartjsColor = Color;

    /**
     * @namespace Chart.helpers
     */
    var helpers = {
        /**
         * An empty function that can be used, for example, for optional callback.
         */
        noop: function () { },

        /**
         * Returns a unique id, sequentially generated from a global variable.
         * @returns {number}
         * @function
         */
        uid: (function () {
            var id = 0;
            return function () {
                return id++;
            };
        }()),

        /**
         * Returns true if `value` is neither null nor undefined, else returns false.
         * @param {*} value - The value to test.
         * @returns {boolean}
         * @since 2.7.0
         */
        isNullOrUndef: function (value) {
            return value === null || typeof value === 'undefined';
        },

        /**
         * Returns true if `value` is an array (including typed arrays), else returns false.
         * @param {*} value - The value to test.
         * @returns {boolean}
         * @function
         */
        isArray: function (value) {
            if (Array.isArray && Array.isArray(value)) {
                return true;
            }
            var type = Object.prototype.toString.call(value);
            if (type.substr(0, 7) === '[object' && type.substr(-6) === 'Array]') {
                return true;
            }
            return false;
        },

        /**
         * Returns true if `value` is an object (excluding null), else returns false.
         * @param {*} value - The value to test.
         * @returns {boolean}
         * @since 2.7.0
         */
        isObject: function (value) {
            return value !== null && Object.prototype.toString.call(value) === '[object Object]';
        },

        /**
         * Returns true if `value` is a finite number, else returns false
         * @param {*} value  - The value to test.
         * @returns {boolean}
         */
        isFinite: function (value) {
            return (typeof value === 'number' || value instanceof Number) && isFinite(value);
        },

        /**
         * Returns `value` if defined, else returns `defaultValue`.
         * @param {*} value - The value to return if defined.
         * @param {*} defaultValue - The value to return if `value` is undefined.
         * @returns {*}
         */
        valueOrDefault: function (value, defaultValue) {
            return typeof value === 'undefined' ? defaultValue : value;
        },

        /**
         * Returns value at the given `index` in array if defined, else returns `defaultValue`.
         * @param {Array} value - The array to lookup for value at `index`.
         * @param {number} index - The index in `value` to lookup for value.
         * @param {*} defaultValue - The value to return if `value[index]` is undefined.
         * @returns {*}
         */
        valueAtIndexOrDefault: function (value, index, defaultValue) {
            return helpers.valueOrDefault(helpers.isArray(value) ? value[index] : value, defaultValue);
        },

        /**
         * Calls `fn` with the given `args` in the scope defined by `thisArg` and returns the
         * value returned by `fn`. If `fn` is not a function, this method returns undefined.
         * @param {function} fn - The function to call.
         * @param {Array|undefined|null} args - The arguments with which `fn` should be called.
         * @param {object} [thisArg] - The value of `this` provided for the call to `fn`.
         * @returns {*}
         */
        callback: function (fn, args, thisArg) {
            if (fn && typeof fn.call === 'function') {
                return fn.apply(thisArg, args);
            }
        },

        /**
         * Note(SB) for performance sake, this method should only be used when loopable type
         * is unknown or in none intensive code (not called often and small loopable). Else
         * it's preferable to use a regular for() loop and save extra function calls.
         * @param {object|Array} loopable - The object or array to be iterated.
         * @param {function} fn - The function to call for each item.
         * @param {object} [thisArg] - The value of `this` provided for the call to `fn`.
         * @param {boolean} [reverse] - If true, iterates backward on the loopable.
         */
        each: function (loopable, fn, thisArg, reverse) {
            var i, len, keys;
            if (helpers.isArray(loopable)) {
                len = loopable.length;
                if (reverse) {
                    for (i = len - 1; i >= 0; i--) {
                        fn.call(thisArg, loopable[i], i);
                    }
                } else {
                    for (i = 0; i < len; i++) {
                        fn.call(thisArg, loopable[i], i);
                    }
                }
            } else if (helpers.isObject(loopable)) {
                keys = Object.keys(loopable);
                len = keys.length;
                for (i = 0; i < len; i++) {
                    fn.call(thisArg, loopable[keys[i]], keys[i]);
                }
            }
        },

        /**
         * Returns true if the `a0` and `a1` arrays have the same content, else returns false.
         * @see https://stackoverflow.com/a/14853974
         * @param {Array} a0 - The array to compare
         * @param {Array} a1 - The array to compare
         * @returns {boolean}
         */
        arrayEquals: function (a0, a1) {
            var i, ilen, v0, v1;

            if (!a0 || !a1 || a0.length !== a1.length) {
                return false;
            }

            for (i = 0, ilen = a0.length; i < ilen; ++i) {
                v0 = a0[i];
                v1 = a1[i];

                if (v0 instanceof Array && v1 instanceof Array) {
                    if (!helpers.arrayEquals(v0, v1)) {
                        return false;
                    }
                } else if (v0 !== v1) {
                    // NOTE: two different object instances will never be equal: {x:20} != {x:20}
                    return false;
                }
            }

            return true;
        },

        /**
         * Returns a deep copy of `source` without keeping references on objects and arrays.
         * @param {*} source - The value to clone.
         * @returns {*}
         */
        clone: function (source) {
            if (helpers.isArray(source)) {
                return source.map(helpers.clone);
            }

            if (helpers.isObject(source)) {
                var target = {};
                var keys = Object.keys(source);
                var klen = keys.length;
                var k = 0;

                for (; k < klen; ++k) {
                    target[keys[k]] = helpers.clone(source[keys[k]]);
                }

                return target;
            }

            return source;
        },

        /**
         * The default merger when Chart.helpers.merge is called without merger option.
         * Note(SB): also used by mergeConfig and mergeScaleConfig as fallback.
         * @private
         */
        _merger: function (key, target, source, options) {
            var tval = target[key];
            var sval = source[key];

            if (helpers.isObject(tval) && helpers.isObject(sval)) {
                helpers.merge(tval, sval, options);
            } else {
                target[key] = helpers.clone(sval);
            }
        },

        /**
         * Merges source[key] in target[key] only if target[key] is undefined.
         * @private
         */
        _mergerIf: function (key, target, source) {
            var tval = target[key];
            var sval = source[key];

            if (helpers.isObject(tval) && helpers.isObject(sval)) {
                helpers.mergeIf(tval, sval);
            } else if (!target.hasOwnProperty(key)) {
                target[key] = helpers.clone(sval);
            }
        },

        /**
         * Recursively deep copies `source` properties into `target` with the given `options`.
         * IMPORTANT: `target` is not cloned and will be updated with `source` properties.
         * @param {object} target - The target object in which all sources are merged into.
         * @param {object|object[]} source - Object(s) to merge into `target`.
         * @param {object} [options] - Merging options:
         * @param {function} [options.merger] - The merge method (key, target, source, options)
         * @returns {object} The `target` object.
         */
        merge: function (target, source, options) {
            var sources = helpers.isArray(source) ? source : [source];
            var ilen = sources.length;
            var merge, i, keys, klen, k;

            if (!helpers.isObject(target)) {
                return target;
            }

            options = options || {};
            merge = options.merger || helpers._merger;

            for (i = 0; i < ilen; ++i) {
                source = sources[i];
                if (!helpers.isObject(source)) {
                    continue;
                }

                keys = Object.keys(source);
                for (k = 0, klen = keys.length; k < klen; ++k) {
                    merge(keys[k], target, source, options);
                }
            }

            return target;
        },

        /**
         * Recursively deep copies `source` properties into `target` *only* if not defined in target.
         * IMPORTANT: `target` is not cloned and will be updated with `source` properties.
         * @param {object} target - The target object in which all sources are merged into.
         * @param {object|object[]} source - Object(s) to merge into `target`.
         * @returns {object} The `target` object.
         */
        mergeIf: function (target, source) {
            return helpers.merge(target, source, { merger: helpers._mergerIf });
        },

        /**
         * Applies the contents of two or more objects together into the first object.
         * @param {object} target - The target object in which all objects are merged into.
         * @param {object} arg1 - Object containing additional properties to merge in target.
         * @param {object} argN - Additional objects containing properties to merge in target.
         * @returns {object} The `target` object.
         */
        extend: function (target) {
            var setFn = function (value, key) {
                target[key] = value;
            };
            for (var i = 1, ilen = arguments.length; i < ilen; ++i) {
                helpers.each(arguments[i], setFn);
            }
            return target;
        },

        /**
         * Basic javascript inheritance based on the model created in Backbone.js
         */
        inherits: function (extensions) {
            var me = this;
            var ChartElement = (extensions && extensions.hasOwnProperty('constructor')) ? extensions.constructor : function () {
                return me.apply(this, arguments);
            };

            var Surrogate = function () {
                this.constructor = ChartElement;
            };

            Surrogate.prototype = me.prototype;
            ChartElement.prototype = new Surrogate();
            ChartElement.extend = helpers.inherits;

            if (extensions) {
                helpers.extend(ChartElement.prototype, extensions);
            }

            ChartElement.__super__ = me.prototype;
            return ChartElement;
        }
    };

    var helpers_core = helpers;

    // DEPRECATIONS

    /**
     * Provided for backward compatibility, use Chart.helpers.callback instead.
     * @function Chart.helpers.callCallback
     * @deprecated since version 2.6.0
     * @todo remove at version 3
     * @private
     */
    helpers.callCallback = helpers.callback;

    /**
     * Provided for backward compatibility, use Array.prototype.indexOf instead.
     * Array.prototype.indexOf compatibility: Chrome, Opera, Safari, FF1.5+, IE9+
     * @function Chart.helpers.indexOf
     * @deprecated since version 2.7.0
     * @todo remove at version 3
     * @private
     */
    helpers.indexOf = function (array, item, fromIndex) {
        return Array.prototype.indexOf.call(array, item, fromIndex);
    };

    /**
     * Provided for backward compatibility, use Chart.helpers.valueOrDefault instead.
     * @function Chart.helpers.getValueOrDefault
     * @deprecated since version 2.7.0
     * @todo remove at version 3
     * @private
     */
    helpers.getValueOrDefault = helpers.valueOrDefault;

    /**
     * Provided for backward compatibility, use Chart.helpers.valueAtIndexOrDefault instead.
     * @function Chart.helpers.getValueAtIndexOrDefault
     * @deprecated since version 2.7.0
     * @todo remove at version 3
     * @private
     */
    helpers.getValueAtIndexOrDefault = helpers.valueAtIndexOrDefault;

    /**
     * Easing functions adapted from Robert Penner's easing equations.
     * @namespace Chart.helpers.easingEffects
     * @see http://www.robertpenner.com/easing/
     */
    var effects = {
        linear: function (t) {
            return t;
        },

        easeInQuad: function (t) {
            return t * t;
        },

        easeOutQuad: function (t) {
            return -t * (t - 2);
        },

        easeInOutQuad: function (t) {
            if ((t /= 0.5) < 1) {
                return 0.5 * t * t;
            }
            return -0.5 * ((--t) * (t - 2) - 1);
        },

        easeInCubic: function (t) {
            return t * t * t;
        },

        easeOutCubic: function (t) {
            return (t = t - 1) * t * t + 1;
        },

        easeInOutCubic: function (t) {
            if ((t /= 0.5) < 1) {
                return 0.5 * t * t * t;
            }
            return 0.5 * ((t -= 2) * t * t + 2);
        },

        easeInQuart: function (t) {
            return t * t * t * t;
        },

        easeOutQuart: function (t) {
            return -((t = t - 1) * t * t * t - 1);
        },

        easeInOutQuart: function (t) {
            if ((t /= 0.5) < 1) {
                return 0.5 * t * t * t * t;
            }
            return -0.5 * ((t -= 2) * t * t * t - 2);
        },

        easeInQuint: function (t) {
            return t * t * t * t * t;
        },

        easeOutQuint: function (t) {
            return (t = t - 1) * t * t * t * t + 1;
        },

        easeInOutQuint: function (t) {
            if ((t /= 0.5) < 1) {
                return 0.5 * t * t * t * t * t;
            }
            return 0.5 * ((t -= 2) * t * t * t * t + 2);
        },

        easeInSine: function (t) {
            return -Math.cos(t * (Math.PI / 2)) + 1;
        },

        easeOutSine: function (t) {
            return Math.sin(t * (Math.PI / 2));
        },

        easeInOutSine: function (t) {
            return -0.5 * (Math.cos(Math.PI * t) - 1);
        },

        easeInExpo: function (t) {
            return (t === 0) ? 0 : Math.pow(2, 10 * (t - 1));
        },

        easeOutExpo: function (t) {
            return (t === 1) ? 1 : -Math.pow(2, -10 * t) + 1;
        },

        easeInOutExpo: function (t) {
            if (t === 0) {
                return 0;
            }
            if (t === 1) {
                return 1;
            }
            if ((t /= 0.5) < 1) {
                return 0.5 * Math.pow(2, 10 * (t - 1));
            }
            return 0.5 * (-Math.pow(2, -10 * --t) + 2);
        },

        easeInCirc: function (t) {
            if (t >= 1) {
                return t;
            }
            return -(Math.sqrt(1 - t * t) - 1);
        },

        easeOutCirc: function (t) {
            return Math.sqrt(1 - (t = t - 1) * t);
        },

        easeInOutCirc: function (t) {
            if ((t /= 0.5) < 1) {
                return -0.5 * (Math.sqrt(1 - t * t) - 1);
            }
            return 0.5 * (Math.sqrt(1 - (t -= 2) * t) + 1);
        },

        easeInElastic: function (t) {
            var s = 1.70158;
            var p = 0;
            var a = 1;
            if (t === 0) {
                return 0;
            }
            if (t === 1) {
                return 1;
            }
            if (!p) {
                p = 0.3;
            }
            if (a < 1) {
                a = 1;
                s = p / 4;
            } else {
                s = p / (2 * Math.PI) * Math.asin(1 / a);
            }
            return -(a * Math.pow(2, 10 * (t -= 1)) * Math.sin((t - s) * (2 * Math.PI) / p));
        },

        easeOutElastic: function (t) {
            var s = 1.70158;
            var p = 0;
            var a = 1;
            if (t === 0) {
                return 0;
            }
            if (t === 1) {
                return 1;
            }
            if (!p) {
                p = 0.3;
            }
            if (a < 1) {
                a = 1;
                s = p / 4;
            } else {
                s = p / (2 * Math.PI) * Math.asin(1 / a);
            }
            return a * Math.pow(2, -10 * t) * Math.sin((t - s) * (2 * Math.PI) / p) + 1;
        },

        easeInOutElastic: function (t) {
            var s = 1.70158;
            var p = 0;
            var a = 1;
            if (t === 0) {
                return 0;
            }
            if ((t /= 0.5) === 2) {
                return 1;
            }
            if (!p) {
                p = 0.45;
            }
            if (a < 1) {
                a = 1;
                s = p / 4;
            } else {
                s = p / (2 * Math.PI) * Math.asin(1 / a);
            }
            if (t < 1) {
                return -0.5 * (a * Math.pow(2, 10 * (t -= 1)) * Math.sin((t - s) * (2 * Math.PI) / p));
            }
            return a * Math.pow(2, -10 * (t -= 1)) * Math.sin((t - s) * (2 * Math.PI) / p) * 0.5 + 1;
        },
        easeInBack: function (t) {
            var s = 1.70158;
            return t * t * ((s + 1) * t - s);
        },

        easeOutBack: function (t) {
            var s = 1.70158;
            return (t = t - 1) * t * ((s + 1) * t + s) + 1;
        },

        easeInOutBack: function (t) {
            var s = 1.70158;
            if ((t /= 0.5) < 1) {
                return 0.5 * (t * t * (((s *= (1.525)) + 1) * t - s));
            }
            return 0.5 * ((t -= 2) * t * (((s *= (1.525)) + 1) * t + s) + 2);
        },

        easeInBounce: function (t) {
            return 1 - effects.easeOutBounce(1 - t);
        },

        easeOutBounce: function (t) {
            if (t < (1 / 2.75)) {
                return 7.5625 * t * t;
            }
            if (t < (2 / 2.75)) {
                return 7.5625 * (t -= (1.5 / 2.75)) * t + 0.75;
            }
            if (t < (2.5 / 2.75)) {
                return 7.5625 * (t -= (2.25 / 2.75)) * t + 0.9375;
            }
            return 7.5625 * (t -= (2.625 / 2.75)) * t + 0.984375;
        },

        easeInOutBounce: function (t) {
            if (t < 0.5) {
                return effects.easeInBounce(t * 2) * 0.5;
            }
            return effects.easeOutBounce(t * 2 - 1) * 0.5 + 0.5;
        }
    };

    var helpers_easing = {
        effects: effects
    };

    // DEPRECATIONS

    /**
     * Provided for backward compatibility, use Chart.helpers.easing.effects instead.
     * @function Chart.helpers.easingEffects
     * @deprecated since version 2.7.0
     * @todo remove at version 3
     * @private
     */
    helpers_core.easingEffects = effects;

    var PI = Math.PI;
    var RAD_PER_DEG = PI / 180;
    var DOUBLE_PI = PI * 2;
    var HALF_PI = PI / 2;
    var QUARTER_PI = PI / 4;
    var TWO_THIRDS_PI = PI * 2 / 3;

    /**
     * @namespace Chart.helpers.canvas
     */
    var exports$1 = {
        /**
         * Clears the entire canvas associated to the given `chart`.
         * @param {Chart} chart - The chart for which to clear the canvas.
         */
        clear: function (chart) {
            chart.ctx.clearRect(0, 0, chart.width, chart.height);
        },

        /**
         * Creates a "path" for a rectangle with rounded corners at position (x, y) with a
         * given size (width, height) and the same `radius` for all corners.
         * @param {CanvasRenderingContext2D} ctx - The canvas 2D Context.
         * @param {number} x - The x axis of the coordinate for the rectangle starting point.
         * @param {number} y - The y axis of the coordinate for the rectangle starting point.
         * @param {number} width - The rectangle's width.
         * @param {number} height - The rectangle's height.
         * @param {number} radius - The rounded amount (in pixels) for the four corners.
         * @todo handle `radius` as top-left, top-right, bottom-right, bottom-left array/object?
         */
        roundedRect: function (ctx, x, y, width, height, radius) {
            if (radius) {
                var r = Math.min(radius, height / 2, width / 2);
                var left = x + r;
                var top = y + r;
                var right = x + width - r;
                var bottom = y + height - r;

                ctx.moveTo(x, top);
                if (left < right && top < bottom) {
                    ctx.arc(left, top, r, -PI, -HALF_PI);
                    ctx.arc(right, top, r, -HALF_PI, 0);
                    ctx.arc(right, bottom, r, 0, HALF_PI);
                    ctx.arc(left, bottom, r, HALF_PI, PI);
                } else if (left < right) {
                    ctx.moveTo(left, y);
                    ctx.arc(right, top, r, -HALF_PI, HALF_PI);
                    ctx.arc(left, top, r, HALF_PI, PI + HALF_PI);
                } else if (top < bottom) {
                    ctx.arc(left, top, r, -PI, 0);
                    ctx.arc(left, bottom, r, 0, PI);
                } else {
                    ctx.arc(left, top, r, -PI, PI);
                }
                ctx.closePath();
                ctx.moveTo(x, y);
            } else {
                ctx.rect(x, y, width, height);
            }
        },

        drawPoint: function (ctx, style, radius, x, y, rotation) {
            var type, xOffset, yOffset, size, cornerRadius;
            var rad = (rotation || 0) * RAD_PER_DEG;

            if (style && typeof style === 'object') {
                type = style.toString();
                if (type === '[object HTMLImageElement]' || type === '[object HTMLCanvasElement]') {
                    ctx.drawImage(style, x - style.width / 2, y - style.height / 2, style.width, style.height);
                    return;
                }
            }

            if (isNaN(radius) || radius <= 0) {
                return;
            }

            ctx.beginPath();

            switch (style) {
                // Default includes circle
                default:
                    ctx.arc(x, y, radius, 0, DOUBLE_PI);
                    ctx.closePath();
                    break;
                case 'triangle':
                    ctx.moveTo(x + Math.sin(rad) * radius, y - Math.cos(rad) * radius);
                    rad += TWO_THIRDS_PI;
                    ctx.lineTo(x + Math.sin(rad) * radius, y - Math.cos(rad) * radius);
                    rad += TWO_THIRDS_PI;
                    ctx.lineTo(x + Math.sin(rad) * radius, y - Math.cos(rad) * radius);
                    ctx.closePath();
                    break;
                case 'rectRounded':
                    // NOTE: the rounded rect implementation changed to use `arc` instead of
                    // `quadraticCurveTo` since it generates better results when rect is
                    // almost a circle. 0.516 (instead of 0.5) produces results with visually
                    // closer proportion to the previous impl and it is inscribed in the
                    // circle with `radius`. For more details, see the following PRs:
                    // https://github.com/chartjs/Chart.js/issues/5597
                    // https://github.com/chartjs/Chart.js/issues/5858
                    cornerRadius = radius * 0.516;
                    size = radius - cornerRadius;
                    xOffset = Math.cos(rad + QUARTER_PI) * size;
                    yOffset = Math.sin(rad + QUARTER_PI) * size;
                    ctx.arc(x - xOffset, y - yOffset, cornerRadius, rad - PI, rad - HALF_PI);
                    ctx.arc(x + yOffset, y - xOffset, cornerRadius, rad - HALF_PI, rad);
                    ctx.arc(x + xOffset, y + yOffset, cornerRadius, rad, rad + HALF_PI);
                    ctx.arc(x - yOffset, y + xOffset, cornerRadius, rad + HALF_PI, rad + PI);
                    ctx.closePath();
                    break;
                case 'rect':
                    if (!rotation) {
                        size = Math.SQRT1_2 * radius;
                        ctx.rect(x - size, y - size, 2 * size, 2 * size);
                        break;
                    }
                    rad += QUARTER_PI;
                /* falls through */
                case 'rectRot':
                    xOffset = Math.cos(rad) * radius;
                    yOffset = Math.sin(rad) * radius;
                    ctx.moveTo(x - xOffset, y - yOffset);
                    ctx.lineTo(x + yOffset, y - xOffset);
                    ctx.lineTo(x + xOffset, y + yOffset);
                    ctx.lineTo(x - yOffset, y + xOffset);
                    ctx.closePath();
                    break;
                case 'crossRot':
                    rad += QUARTER_PI;
                /* falls through */
                case 'cross':
                    xOffset = Math.cos(rad) * radius;
                    yOffset = Math.sin(rad) * radius;
                    ctx.moveTo(x - xOffset, y - yOffset);
                    ctx.lineTo(x + xOffset, y + yOffset);
                    ctx.moveTo(x + yOffset, y - xOffset);
                    ctx.lineTo(x - yOffset, y + xOffset);
                    break;
                case 'star':
                    xOffset = Math.cos(rad) * radius;
                    yOffset = Math.sin(rad) * radius;
                    ctx.moveTo(x - xOffset, y - yOffset);
                    ctx.lineTo(x + xOffset, y + yOffset);
                    ctx.moveTo(x + yOffset, y - xOffset);
                    ctx.lineTo(x - yOffset, y + xOffset);
                    rad += QUARTER_PI;
                    xOffset = Math.cos(rad) * radius;
                    yOffset = Math.sin(rad) * radius;
                    ctx.moveTo(x - xOffset, y - yOffset);
                    ctx.lineTo(x + xOffset, y + yOffset);
                    ctx.moveTo(x + yOffset, y - xOffset);
                    ctx.lineTo(x - yOffset, y + xOffset);
                    break;
                case 'line':
                    xOffset = Math.cos(rad) * radius;
                    yOffset = Math.sin(rad) * radius;
                    ctx.moveTo(x - xOffset, y - yOffset);
                    ctx.lineTo(x + xOffset, y + yOffset);
                    break;
                case 'dash':
                    ctx.moveTo(x, y);
                    ctx.lineTo(x + Math.cos(rad) * radius, y + Math.sin(rad) * radius);
                    break;
            }

            ctx.fill();
            ctx.stroke();
        },

        /**
         * Returns true if the point is inside the rectangle
         * @param {object} point - The point to test
         * @param {object} area - The rectangle
         * @returns {boolean}
         * @private
         */
        _isPointInArea: function (point, area) {
            var epsilon = 1e-6; // 1e-6 is margin in pixels for accumulated error.

            return point.x > area.left - epsilon && point.x < area.right + epsilon &&
                point.y > area.top - epsilon && point.y < area.bottom + epsilon;
        },

        clipArea: function (ctx, area) {
            ctx.save();
            ctx.beginPath();
            ctx.rect(area.left, area.top, area.right - area.left, area.bottom - area.top);
            ctx.clip();
        },

        unclipArea: function (ctx) {
            ctx.restore();
        },

        lineTo: function (ctx, previous, target, flip) {
            var stepped = target.steppedLine;
            if (stepped) {
                if (stepped === 'middle') {
                    var midpoint = (previous.x + target.x) / 2.0;
                    ctx.lineTo(midpoint, flip ? target.y : previous.y);
                    ctx.lineTo(midpoint, flip ? previous.y : target.y);
                } else if ((stepped === 'after' && !flip) || (stepped !== 'after' && flip)) {
                    ctx.lineTo(previous.x, target.y);
                } else {
                    ctx.lineTo(target.x, previous.y);
                }
                ctx.lineTo(target.x, target.y);
                return;
            }

            if (!target.tension) {
                ctx.lineTo(target.x, target.y);
                return;
            }

            ctx.bezierCurveTo(
                flip ? previous.controlPointPreviousX : previous.controlPointNextX,
                flip ? previous.controlPointPreviousY : previous.controlPointNextY,
                flip ? target.controlPointNextX : target.controlPointPreviousX,
                flip ? target.controlPointNextY : target.controlPointPreviousY,
                target.x,
                target.y);
        }
    };

    var helpers_canvas = exports$1;

    // DEPRECATIONS

    /**
     * Provided for backward compatibility, use Chart.helpers.canvas.clear instead.
     * @namespace Chart.helpers.clear
     * @deprecated since version 2.7.0
     * @todo remove at version 3
     * @private
     */
    helpers_core.clear = exports$1.clear;

    /**
     * Provided for backward compatibility, use Chart.helpers.canvas.roundedRect instead.
     * @namespace Chart.helpers.drawRoundedRectangle
     * @deprecated since version 2.7.0
     * @todo remove at version 3
     * @private
     */
    helpers_core.drawRoundedRectangle = function (ctx) {
        ctx.beginPath();
        exports$1.roundedRect.apply(exports$1, arguments);
    };

    var defaults = {
        /**
         * @private
         */
        _set: function (scope, values) {
            return helpers_core.merge(this[scope] || (this[scope] = {}), values);
        }
    };

    defaults._set('global', {
        defaultColor: 'rgba(0,0,0,0.1)',
        defaultFontColor: '#666',
        defaultFontFamily: "'Helvetica Neue', 'Helvetica', 'Arial', sans-serif",
        defaultFontSize: 12,
        defaultFontStyle: 'normal',
        defaultLineHeight: 1.2,
        showLines: true
    });

    var core_defaults = defaults;

    var valueOrDefault = helpers_core.valueOrDefault;

    /**
     * Converts the given font object into a CSS font string.
     * @param {object} font - A font object.
     * @return {string} The CSS font string. See https://developer.mozilla.org/en-US/docs/Web/CSS/font
     * @private
     */
    function toFontString(font) {
        if (!font || helpers_core.isNullOrUndef(font.size) || helpers_core.isNullOrUndef(font.family)) {
            return null;
        }

        return (font.style ? font.style + ' ' : '')
            + (font.weight ? font.weight + ' ' : '')
            + font.size + 'px '
            + font.family;
    }

    /**
     * @alias Chart.helpers.options
     * @namespace
     */
    var helpers_options = {
        /**
         * Converts the given line height `value` in pixels for a specific font `size`.
         * @param {number|string} value - The lineHeight to parse (eg. 1.6, '14px', '75%', '1.6em').
         * @param {number} size - The font size (in pixels) used to resolve relative `value`.
         * @returns {number} The effective line height in pixels (size * 1.2 if value is invalid).
         * @see https://developer.mozilla.org/en-US/docs/Web/CSS/line-height
         * @since 2.7.0
         */
        toLineHeight: function (value, size) {
            var matches = ('' + value).match(/^(normal|(\d+(?:\.\d+)?)(px|em|%)?)$/);
            if (!matches || matches[1] === 'normal') {
                return size * 1.2;
            }

            value = +matches[2];

            switch (matches[3]) {
                case 'px':
                    return value;
                case '%':
                    value /= 100;
                    break;
                default:
                    break;
            }

            return size * value;
        },

        /**
         * Converts the given value into a padding object with pre-computed width/height.
         * @param {number|object} value - If a number, set the value to all TRBL component,
         *  else, if and object, use defined properties and sets undefined ones to 0.
         * @returns {object} The padding values (top, right, bottom, left, width, height)
         * @since 2.7.0
         */
        toPadding: function (value) {
            var t, r, b, l;

            if (helpers_core.isObject(value)) {
                t = +value.top || 0;
                r = +value.right || 0;
                b = +value.bottom || 0;
                l = +value.left || 0;
            } else {
                t = r = b = l = +value || 0;
            }

            return {
                top: t,
                right: r,
                bottom: b,
                left: l,
                height: t + b,
                width: l + r
            };
        },

        /**
         * Parses font options and returns the font object.
         * @param {object} options - A object that contains font options to be parsed.
         * @return {object} The font object.
         * @todo Support font.* options and renamed to toFont().
         * @private
         */
        _parseFont: function (options) {
            var globalDefaults = core_defaults.global;
            var size = valueOrDefault(options.fontSize, globalDefaults.defaultFontSize);
            var font = {
                family: valueOrDefault(options.fontFamily, globalDefaults.defaultFontFamily),
                lineHeight: helpers_core.options.toLineHeight(valueOrDefault(options.lineHeight, globalDefaults.defaultLineHeight), size),
                size: size,
                style: valueOrDefault(options.fontStyle, globalDefaults.defaultFontStyle),
                weight: null,
                string: ''
            };

            font.string = toFontString(font);
            return font;
        },

        /**
         * Evaluates the given `inputs` sequentially and returns the first defined value.
         * @param {Array} inputs - An array of values, falling back to the last value.
         * @param {object} [context] - If defined and the current value is a function, the value
         * is called with `context` as first argument and the result becomes the new input.
         * @param {number} [index] - If defined and the current value is an array, the value
         * at `index` become the new input.
         * @since 2.7.0
         */
        resolve: function (inputs, context, index) {
            var i, ilen, value;

            for (i = 0, ilen = inputs.length; i < ilen; ++i) {
                value = inputs[i];
                if (value === undefined) {
                    continue;
                }
                if (context !== undefined && typeof value === 'function') {
                    value = value(context);
                }
                if (index !== undefined && helpers_core.isArray(value)) {
                    value = value[index];
                }
                if (value !== undefined) {
                    return value;
                }
            }
        }
    };

    var helpers$1 = helpers_core;
    var easing = helpers_easing;
    var canvas = helpers_canvas;
    var options = helpers_options;
    helpers$1.easing = easing;
    helpers$1.canvas = canvas;
    helpers$1.options = options;

    function interpolate(start, view, model, ease) {
        var keys = Object.keys(model);
        var i, ilen, key, actual, origin, target, type, c0, c1;

        for (i = 0, ilen = keys.length; i < ilen; ++i) {
            key = keys[i];

            target = model[key];

            // if a value is added to the model after pivot() has been called, the view
            // doesn't contain it, so let's initialize the view to the target value.
            if (!view.hasOwnProperty(key)) {
                view[key] = target;
            }

            actual = view[key];

            if (actual === target || key[0] === '_') {
                continue;
            }

            if (!start.hasOwnProperty(key)) {
                start[key] = actual;
            }

            origin = start[key];

            type = typeof target;

            if (type === typeof origin) {
                if (type === 'string') {
                    c0 = chartjsColor(origin);
                    if (c0.valid) {
                        c1 = chartjsColor(target);
                        if (c1.valid) {
                            view[key] = c1.mix(c0, ease).rgbString();
                            continue;
                        }
                    }
                } else if (helpers$1.isFinite(origin) && helpers$1.isFinite(target)) {
                    view[key] = origin + (target - origin) * ease;
                    continue;
                }
            }

            view[key] = target;
        }
    }

    var Element = function (configuration) {
        helpers$1.extend(this, configuration);
        this.initialize.apply(this, arguments);
    };

    helpers$1.extend(Element.prototype, {

        initialize: function () {
            this.hidden = false;
        },

        pivot: function () {
            var me = this;
            if (!me._view) {
                me._view = helpers$1.clone(me._model);
            }
            me._start = {};
            return me;
        },

        transition: function (ease) {
            var me = this;
            var model = me._model;
            var start = me._start;
            var view = me._view;

            // No animation -> No Transition
            if (!model || ease === 1) {
                me._view = model;
                me._start = null;
                return me;
            }

            if (!view) {
                view = me._view = {};
            }

            if (!start) {
                start = me._start = {};
            }

            interpolate(start, view, model, ease);

            return me;
        },

        tooltipPosition: function () {
            return {
                x: this._model.x,
                y: this._model.y
            };
        },

        hasValue: function () {
            return helpers$1.isNumber(this._model.x) && helpers$1.isNumber(this._model.y);
        }
    });

    Element.extend = helpers$1.inherits;

    var core_element = Element;

    var exports$2 = core_element.extend({
        chart: null, // the animation associated chart instance
        currentStep: 0, // the current animation step
        numSteps: 60, // default number of steps
        easing: '', // the easing to use for this animation
        render: null, // render function used by the animation service

        onAnimationProgress: null, // user specified callback to fire on each step of the animation
        onAnimationComplete: null, // user specified callback to fire when the animation finishes
    });

    var core_animation = exports$2;

    // DEPRECATIONS

    /**
     * Provided for backward compatibility, use Chart.Animation instead
     * @prop Chart.Animation#animationObject
     * @deprecated since version 2.6.0
     * @todo remove at version 3
     */
    Object.defineProperty(exports$2.prototype, 'animationObject', {
        get: function () {
            return this;
        }
    });

    /**
     * Provided for backward compatibility, use Chart.Animation#chart instead
     * @prop Chart.Animation#chartInstance
     * @deprecated since version 2.6.0
     * @todo remove at version 3
     */
    Object.defineProperty(exports$2.prototype, 'chartInstance', {
        get: function () {
            return this.chart;
        },
        set: function (value) {
            this.chart = value;
        }
    });

    core_defaults._set('global', {
        animation: {
            duration: 1000,
            easing: 'easeOutQuart',
            onProgress: helpers$1.noop,
            onComplete: helpers$1.noop
        }
    });

    var core_animations = {
        animations: [],
        request: null,

        /**
         * @param {Chart} chart - The chart to animate.
         * @param {Chart.Animation} animation - The animation that we will animate.
         * @param {number} duration - The animation duration in ms.
         * @param {boolean} lazy - if true, the chart is not marked as animating to enable more responsive interactions
         */
        addAnimation: function (chart, animation, duration, lazy) {
            var animations = this.animations;
            var i, ilen;

            animation.chart = chart;
            animation.startTime = Date.now();
            animation.duration = duration;

            if (!lazy) {
                chart.animating = true;
            }

            for (i = 0, ilen = animations.length; i < ilen; ++i) {
                if (animations[i].chart === chart) {
                    animations[i] = animation;
                    return;
                }
            }

            animations.push(animation);

            // If there are no animations queued, manually kickstart a digest, for lack of a better word
            if (animations.length === 1) {
                this.requestAnimationFrame();
            }
        },

        cancelAnimation: function (chart) {
            var index = helpers$1.findIndex(this.animations, function (animation) {
                return animation.chart === chart;
            });

            if (index !== -1) {
                this.animations.splice(index, 1);
                chart.animating = false;
            }
        },

        requestAnimationFrame: function () {
            var me = this;
            if (me.request === null) {
                // Skip animation frame requests until the active one is executed.
                // This can happen when processing mouse events, e.g. 'mousemove'
                // and 'mouseout' events will trigger multiple renders.
                me.request = helpers$1.requestAnimFrame.call(window, function () {
                    me.request = null;
                    me.startDigest();
                });
            }
        },

        /**
         * @private
         */
        startDigest: function () {
            var me = this;

            me.advance();

            // Do we have more stuff to animate?
            if (me.animations.length > 0) {
                me.requestAnimationFrame();
            }
        },

        /**
         * @private
         */
        advance: function () {
            var animations = this.animations;
            var animation, chart, numSteps, nextStep;
            var i = 0;

            // 1 animation per chart, so we are looping charts here
            while (i < animations.length) {
                animation = animations[i];
                chart = animation.chart;
                numSteps = animation.numSteps;

                // Make sure that currentStep starts at 1
                // https://github.com/chartjs/Chart.js/issues/6104
                nextStep = Math.floor((Date.now() - animation.startTime) / animation.duration * numSteps) + 1;
                animation.currentStep = Math.min(nextStep, numSteps);

                helpers$1.callback(animation.render, [chart, animation], chart);
                helpers$1.callback(animation.onAnimationProgress, [animation], chart);

                if (animation.currentStep >= numSteps) {
                    helpers$1.callback(animation.onAnimationComplete, [animation], chart);
                    chart.animating = false;
                    animations.splice(i, 1);
                } else {
                    ++i;
                }
            }
        }
    };

    var resolve = helpers$1.options.resolve;

    var arrayEvents = ['push', 'pop', 'shift', 'splice', 'unshift'];

    /**
     * Hooks the array methods that add or remove values ('push', pop', 'shift', 'splice',
     * 'unshift') and notify the listener AFTER the array has been altered. Listeners are
     * called on the 'onData*' callbacks (e.g. onDataPush, etc.) with same arguments.
     */
    function listenArrayEvents(array, listener) {
        if (array._chartjs) {
            array._chartjs.listeners.push(listener);
            return;
        }

        Object.defineProperty(array, '_chartjs', {
            configurable: true,
            enumerable: false,
            value: {
                listeners: [listener]
            }
        });

        arrayEvents.forEach(function (key) {
            var method = 'onData' + key.charAt(0).toUpperCase() + key.slice(1);
            var base = array[key];

            Object.defineProperty(array, key, {
                configurable: true,
                enumerable: false,
                value: function () {
                    var args = Array.prototype.slice.call(arguments);
                    var res = base.apply(this, args);

                    helpers$1.each(array._chartjs.listeners, function (object) {
                        if (typeof object[method] === 'function') {
                            object[method].apply(object, args);
                        }
                    });

                    return res;
                }
            });
        });
    }

    /**
     * Removes the given array event listener and cleanup extra attached properties (such as
     * the _chartjs stub and overridden methods) if array doesn't have any more listeners.
     */
    function unlistenArrayEvents(array, listener) {
        var stub = array._chartjs;
        if (!stub) {
            return;
        }

        var listeners = stub.listeners;
        var index = listeners.indexOf(listener);
        if (index !== -1) {
            listeners.splice(index, 1);
        }

        if (listeners.length > 0) {
            return;
        }

        arrayEvents.forEach(function (key) {
            delete array[key];
        });

        delete array._chartjs;
    }

    // Base class for all dataset controllers (line, bar, etc)
    var DatasetController = function (chart, datasetIndex) {
        this.initialize(chart, datasetIndex);
    };

    helpers$1.extend(DatasetController.prototype, {

        /**
         * Element type used to generate a meta dataset (e.g. Chart.element.Line).
         * @type {Chart.core.element}
         */
        datasetElementType: null,

        /**
         * Element type used to generate a meta data (e.g. Chart.element.Point).
         * @type {Chart.core.element}
         */
        dataElementType: null,

        initialize: function (chart, datasetIndex) {
            var me = this;
            me.chart = chart;
            me.index = datasetIndex;
            me.linkScales();
            me.addElements();
        },

        updateIndex: function (datasetIndex) {
            this.index = datasetIndex;
        },

        linkScales: function () {
            var me = this;
            var meta = me.getMeta();
            var dataset = me.getDataset();

            if (meta.xAxisID === null || !(meta.xAxisID in me.chart.scales)) {
                meta.xAxisID = dataset.xAxisID || me.chart.options.scales.xAxes[0].id;
            }
            if (meta.yAxisID === null || !(meta.yAxisID in me.chart.scales)) {
                meta.yAxisID = dataset.yAxisID || me.chart.options.scales.yAxes[0].id;
            }
        },

        getDataset: function () {
            return this.chart.data.datasets[this.index];
        },

        getMeta: function () {
            return this.chart.getDatasetMeta(this.index);
        },

        getScaleForId: function (scaleID) {
            return this.chart.scales[scaleID];
        },

        /**
         * @private
         */
        _getValueScaleId: function () {
            return this.getMeta().yAxisID;
        },

        /**
         * @private
         */
        _getIndexScaleId: function () {
            return this.getMeta().xAxisID;
        },

        /**
         * @private
         */
        _getValueScale: function () {
            return this.getScaleForId(this._getValueScaleId());
        },

        /**
         * @private
         */
        _getIndexScale: function () {
            return this.getScaleForId(this._getIndexScaleId());
        },

        reset: function () {
            this.update(true);
        },

        /**
         * @private
         */
        destroy: function () {
            if (this._data) {
                unlistenArrayEvents(this._data, this);
            }
        },

        createMetaDataset: function () {
            var me = this;
            var type = me.datasetElementType;
            return type && new type({
                _chart: me.chart,
                _datasetIndex: me.index
            });
        },

        createMetaData: function (index) {
            var me = this;
            var type = me.dataElementType;
            return type && new type({
                _chart: me.chart,
                _datasetIndex: me.index,
                _index: index
            });
        },

        addElements: function () {
            var me = this;
            var meta = me.getMeta();
            var data = me.getDataset().data || [];
            var metaData = meta.data;
            var i, ilen;

            for (i = 0, ilen = data.length; i < ilen; ++i) {
                metaData[i] = metaData[i] || me.createMetaData(i);
            }

            meta.dataset = meta.dataset || me.createMetaDataset();
        },

        addElementAndReset: function (index) {
            var element = this.createMetaData(index);
            this.getMeta().data.splice(index, 0, element);
            this.updateElement(element, index, true);
        },

        buildOrUpdateElements: function () {
            var me = this;
            var dataset = me.getDataset();
            var data = dataset.data || (dataset.data = []);

            // In order to correctly handle data addition/deletion animation (an thus simulate
            // real-time charts), we need to monitor these data modifications and synchronize
            // the internal meta data accordingly.
            if (me._data !== data) {
                if (me._data) {
                    // This case happens when the user replaced the data array instance.
                    unlistenArrayEvents(me._data, me);
                }

                if (data && Object.isExtensible(data)) {
                    listenArrayEvents(data, me);
                }
                me._data = data;
            }

            // Re-sync meta data in case the user replaced the data array or if we missed
            // any updates and so make sure that we handle number of datapoints changing.
            me.resyncElements();
        },

        update: helpers$1.noop,

        transition: function (easingValue) {
            var meta = this.getMeta();
            var elements = meta.data || [];
            var ilen = elements.length;
            var i = 0;

            for (; i < ilen; ++i) {
                elements[i].transition(easingValue);
            }

            if (meta.dataset) {
                meta.dataset.transition(easingValue);
            }
        },

        draw: function () {
            var meta = this.getMeta();
            var elements = meta.data || [];
            var ilen = elements.length;
            var i = 0;

            if (meta.dataset) {
                meta.dataset.draw();
            }

            for (; i < ilen; ++i) {
                elements[i].draw();
            }
        },

        removeHoverStyle: function (element) {
            helpers$1.merge(element._model, element.$previousStyle || {});
            delete element.$previousStyle;
        },

        setHoverStyle: function (element) {
            var dataset = this.chart.data.datasets[element._datasetIndex];
            var index = element._index;
            var custom = element.custom || {};
            var model = element._model;
            var getHoverColor = helpers$1.getHoverColor;

            element.$previousStyle = {
                backgroundColor: model.backgroundColor,
                borderColor: model.borderColor,
                borderWidth: model.borderWidth
            };

            model.backgroundColor = resolve([custom.hoverBackgroundColor, dataset.hoverBackgroundColor, getHoverColor(model.backgroundColor)], undefined, index);
            model.borderColor = resolve([custom.hoverBorderColor, dataset.hoverBorderColor, getHoverColor(model.borderColor)], undefined, index);
            model.borderWidth = resolve([custom.hoverBorderWidth, dataset.hoverBorderWidth, model.borderWidth], undefined, index);
        },

        /**
         * @private
         */
        resyncElements: function () {
            var me = this;
            var meta = me.getMeta();
            var data = me.getDataset().data;
            var numMeta = meta.data.length;
            var numData = data.length;

            if (numData < numMeta) {
                meta.data.splice(numData, numMeta - numData);
            } else if (numData > numMeta) {
                me.insertElements(numMeta, numData - numMeta);
            }
        },

        /**
         * @private
         */
        insertElements: function (start, count) {
            for (var i = 0; i < count; ++i) {
                this.addElementAndReset(start + i);
            }
        },

        /**
         * @private
         */
        onDataPush: function () {
            var count = arguments.length;
            this.insertElements(this.getDataset().data.length - count, count);
        },

        /**
         * @private
         */
        onDataPop: function () {
            this.getMeta().data.pop();
        },

        /**
         * @private
         */
        onDataShift: function () {
            this.getMeta().data.shift();
        },

        /**
         * @private
         */
        onDataSplice: function (start, count) {
            this.getMeta().data.splice(start, count);
            this.insertElements(start, arguments.length - 2);
        },

        /**
         * @private
         */
        onDataUnshift: function () {
            this.insertElements(0, arguments.length);
        }
    });

    DatasetController.extend = helpers$1.inherits;

    var core_datasetController = DatasetController;

    core_defaults._set('global', {
        elements: {
            arc: {
                backgroundColor: core_defaults.global.defaultColor,
                borderColor: '#fff',
                borderWidth: 2,
                borderAlign: 'center'
            }
        }
    });

    var element_arc = core_element.extend({
        inLabelRange: function (mouseX) {
            var vm = this._view;

            if (vm) {
                return (Math.pow(mouseX - vm.x, 2) < Math.pow(vm.radius + vm.hoverRadius, 2));
            }
            return false;
        },

        inRange: function (chartX, chartY) {
            var vm = this._view;

            if (vm) {
                var pointRelativePosition = helpers$1.getAngleFromPoint(vm, { x: chartX, y: chartY });
                var angle = pointRelativePosition.angle;
                var distance = pointRelativePosition.distance;

                // Sanitise angle range
                var startAngle = vm.startAngle;
                var endAngle = vm.endAngle;
                while (endAngle < startAngle) {
                    endAngle += 2.0 * Math.PI;
                }
                while (angle > endAngle) {
                    angle -= 2.0 * Math.PI;
                }
                while (angle < startAngle) {
                    angle += 2.0 * Math.PI;
                }

                // Check if within the range of the open/close angle
                var betweenAngles = (angle >= startAngle && angle <= endAngle);
                var withinRadius = (distance >= vm.innerRadius && distance <= vm.outerRadius);

                return (betweenAngles && withinRadius);
            }
            return false;
        },

        getCenterPoint: function () {
            var vm = this._view;
            var halfAngle = (vm.startAngle + vm.endAngle) / 2;
            var halfRadius = (vm.innerRadius + vm.outerRadius) / 2;
            return {
                x: vm.x + Math.cos(halfAngle) * halfRadius,
                y: vm.y + Math.sin(halfAngle) * halfRadius
            };
        },

        getArea: function () {
            var vm = this._view;
            return Math.PI * ((vm.endAngle - vm.startAngle) / (2 * Math.PI)) * (Math.pow(vm.outerRadius, 2) - Math.pow(vm.innerRadius, 2));
        },

        tooltipPosition: function () {
            var vm = this._view;
            var centreAngle = vm.startAngle + ((vm.endAngle - vm.startAngle) / 2);
            var rangeFromCentre = (vm.outerRadius - vm.innerRadius) / 2 + vm.innerRadius;

            return {
                x: vm.x + (Math.cos(centreAngle) * rangeFromCentre),
                y: vm.y + (Math.sin(centreAngle) * rangeFromCentre)
            };
        },

        draw: function () {
            var ctx = this._chart.ctx;
            var vm = this._view;
            var sA = vm.startAngle;
            var eA = vm.endAngle;
            var pixelMargin = (vm.borderAlign === 'inner') ? 0.33 : 0;
            var angleMargin;

            ctx.save();

            ctx.beginPath();
            ctx.arc(vm.x, vm.y, Math.max(vm.outerRadius - pixelMargin, 0), sA, eA);
            ctx.arc(vm.x, vm.y, vm.innerRadius, eA, sA, true);
            ctx.closePath();

            ctx.fillStyle = vm.backgroundColor;
            ctx.fill();

            if (vm.borderWidth) {
                if (vm.borderAlign === 'inner') {
                    // Draw an inner border by cliping the arc and drawing a double-width border
                    // Enlarge the clipping arc by 0.33 pixels to eliminate glitches between borders
                    ctx.beginPath();
                    angleMargin = pixelMargin / vm.outerRadius;
                    ctx.arc(vm.x, vm.y, vm.outerRadius, sA - angleMargin, eA + angleMargin);
                    if (vm.innerRadius > pixelMargin) {
                        angleMargin = pixelMargin / vm.innerRadius;
                        ctx.arc(vm.x, vm.y, vm.innerRadius - pixelMargin, eA + angleMargin, sA - angleMargin, true);
                    } else {
                        ctx.arc(vm.x, vm.y, pixelMargin, eA + Math.PI / 2, sA - Math.PI / 2);
                    }
                    ctx.closePath();
                    ctx.clip();

                    ctx.beginPath();
                    ctx.arc(vm.x, vm.y, vm.outerRadius, sA, eA);
                    ctx.arc(vm.x, vm.y, vm.innerRadius, eA, sA, true);
                    ctx.closePath();

                    ctx.lineWidth = vm.borderWidth * 2;
                    ctx.lineJoin = 'round';
                } else {
                    ctx.lineWidth = vm.borderWidth;
                    ctx.lineJoin = 'bevel';
                }

                ctx.strokeStyle = vm.borderColor;
                ctx.stroke();
            }

            ctx.restore();
        }
    });

    var valueOrDefault$1 = helpers$1.valueOrDefault;

    var defaultColor = core_defaults.global.defaultColor;

    core_defaults._set('global', {
        elements: {
            line: {
                tension: 0.4,
                backgroundColor: defaultColor,
                borderWidth: 3,
                borderColor: defaultColor,
                borderCapStyle: 'butt',
                borderDash: [],
                borderDashOffset: 0.0,
                borderJoinStyle: 'miter',
                capBezierPoints: true,
                fill: true, // do we fill in the area between the line and its base axis
            }
        }
    });

    var element_line = core_element.extend({
        draw: function () {
            var me = this;
            var vm = me._view;
            var ctx = me._chart.ctx;
            var spanGaps = vm.spanGaps;
            var points = me._children.slice(); // clone array
            var globalDefaults = core_defaults.global;
            var globalOptionLineElements = globalDefaults.elements.line;
            var lastDrawnIndex = -1;
            var index, current, previous, currentVM;

            // If we are looping, adding the first point again
            if (me._loop && points.length) {
                points.push(points[0]);
            }

            ctx.save();

            // Stroke Line Options
            ctx.lineCap = vm.borderCapStyle || globalOptionLineElements.borderCapStyle;

            // IE 9 and 10 do not support line dash
            if (ctx.setLineDash) {
                ctx.setLineDash(vm.borderDash || globalOptionLineElements.borderDash);
            }

            ctx.lineDashOffset = valueOrDefault$1(vm.borderDashOffset, globalOptionLineElements.borderDashOffset);
            ctx.lineJoin = vm.borderJoinStyle || globalOptionLineElements.borderJoinStyle;
            ctx.lineWidth = valueOrDefault$1(vm.borderWidth, globalOptionLineElements.borderWidth);
            ctx.strokeStyle = vm.borderColor || globalDefaults.defaultColor;

            // Stroke Line
            ctx.beginPath();
            lastDrawnIndex = -1;

            for (index = 0; index < points.length; ++index) {
                current = points[index];
                previous = helpers$1.previousItem(points, index);
                currentVM = current._view;

                // First point moves to it's starting position no matter what
                if (index === 0) {
                    if (!currentVM.skip) {
                        ctx.moveTo(currentVM.x, currentVM.y);
                        lastDrawnIndex = index;
                    }
                } else {
                    previous = lastDrawnIndex === -1 ? previous : points[lastDrawnIndex];

                    if (!currentVM.skip) {
                        if ((lastDrawnIndex !== (index - 1) && !spanGaps) || lastDrawnIndex === -1) {
                            // There was a gap and this is the first point after the gap
                            ctx.moveTo(currentVM.x, currentVM.y);
                        } else {
                            // Line to next point
                            helpers$1.canvas.lineTo(ctx, previous._view, current._view);
                        }
                        lastDrawnIndex = index;
                    }
                }
            }

            ctx.stroke();
            ctx.restore();
        }
    });

    var valueOrDefault$2 = helpers$1.valueOrDefault;

    var defaultColor$1 = core_defaults.global.defaultColor;

    core_defaults._set('global', {
        elements: {
            point: {
                radius: 3,
                pointStyle: 'circle',
                backgroundColor: defaultColor$1,
                borderColor: defaultColor$1,
                borderWidth: 1,
                // Hover
                hitRadius: 1,
                hoverRadius: 4,
                hoverBorderWidth: 1
            }
        }
    });

    function xRange(mouseX) {
        var vm = this._view;
        return vm ? (Math.abs(mouseX - vm.x) < vm.radius + vm.hitRadius) : false;
    }

    function yRange(mouseY) {
        var vm = this._view;
        return vm ? (Math.abs(mouseY - vm.y) < vm.radius + vm.hitRadius) : false;
    }

    var element_point = core_element.extend({
        inRange: function (mouseX, mouseY) {
            var vm = this._view;
            return vm ? ((Math.pow(mouseX - vm.x, 2) + Math.pow(mouseY - vm.y, 2)) < Math.pow(vm.hitRadius + vm.radius, 2)) : false;
        },

        inLabelRange: xRange,
        inXRange: xRange,
        inYRange: yRange,

        getCenterPoint: function () {
            var vm = this._view;
            return {
                x: vm.x,
                y: vm.y
            };
        },

        getArea: function () {
            return Math.PI * Math.pow(this._view.radius, 2);
        },

        tooltipPosition: function () {
            var vm = this._view;
            return {
                x: vm.x,
                y: vm.y,
                padding: vm.radius + vm.borderWidth
            };
        },

        draw: function (chartArea) {
            var vm = this._view;
            var ctx = this._chart.ctx;
            var pointStyle = vm.pointStyle;
            var rotation = vm.rotation;
            var radius = vm.radius;
            var x = vm.x;
            var y = vm.y;
            var globalDefaults = core_defaults.global;
            var defaultColor = globalDefaults.defaultColor; // eslint-disable-line no-shadow

            if (vm.skip) {
                return;
            }

            // Clipping for Points.
            if (chartArea === undefined || helpers$1.canvas._isPointInArea(vm, chartArea)) {
                ctx.strokeStyle = vm.borderColor || defaultColor;
                ctx.lineWidth = valueOrDefault$2(vm.borderWidth, globalDefaults.elements.point.borderWidth);
                ctx.fillStyle = vm.backgroundColor || defaultColor;
                helpers$1.canvas.drawPoint(ctx, pointStyle, radius, x, y, rotation);
            }
        }
    });

    var defaultColor$2 = core_defaults.global.defaultColor;

    core_defaults._set('global', {
        elements: {
            rectangle: {
                backgroundColor: defaultColor$2,
                borderColor: defaultColor$2,
                borderSkipped: 'bottom',
                borderWidth: 0
            }
        }
    });

    function isVertical(vm) {
        return vm && vm.width !== undefined;
    }

    /**
     * Helper function to get the bounds of the bar regardless of the orientation
     * @param bar {Chart.Element.Rectangle} the bar
     * @return {Bounds} bounds of the bar
     * @private
     */
    function getBarBounds(vm) {
        var x1, x2, y1, y2, half;

        if (isVertical(vm)) {
            half = vm.width / 2;
            x1 = vm.x - half;
            x2 = vm.x + half;
            y1 = Math.min(vm.y, vm.base);
            y2 = Math.max(vm.y, vm.base);
        } else {
            half = vm.height / 2;
            x1 = Math.min(vm.x, vm.base);
            x2 = Math.max(vm.x, vm.base);
            y1 = vm.y - half;
            y2 = vm.y + half;
        }

        return {
            left: x1,
            top: y1,
            right: x2,
            bottom: y2
        };
    }

    function swap(orig, v1, v2) {
        return orig === v1 ? v2 : orig === v2 ? v1 : orig;
    }

    function parseBorderSkipped(vm) {
        var edge = vm.borderSkipped;
        var res = {};

        if (!edge) {
            return res;
        }

        if (vm.horizontal) {
            if (vm.base > vm.x) {
                edge = swap(edge, 'left', 'right');
            }
        } else if (vm.base < vm.y) {
            edge = swap(edge, 'bottom', 'top');
        }

        res[edge] = true;
        return res;
    }

    function parseBorderWidth(vm, maxW, maxH) {
        var value = vm.borderWidth;
        var skip = parseBorderSkipped(vm);
        var t, r, b, l;

        if (helpers$1.isObject(value)) {
            t = +value.top || 0;
            r = +value.right || 0;
            b = +value.bottom || 0;
            l = +value.left || 0;
        } else {
            t = r = b = l = +value || 0;
        }

        return {
            t: skip.top || (t < 0) ? 0 : t > maxH ? maxH : t,
            r: skip.right || (r < 0) ? 0 : r > maxW ? maxW : r,
            b: skip.bottom || (b < 0) ? 0 : b > maxH ? maxH : b,
            l: skip.left || (l < 0) ? 0 : l > maxW ? maxW : l
        };
    }

    function boundingRects(vm) {
        var bounds = getBarBounds(vm);
        var width = bounds.right - bounds.left;
        var height = bounds.bottom - bounds.top;
        var border = parseBorderWidth(vm, width / 2, height / 2);

        return {
            outer: {
                x: bounds.left,
                y: bounds.top,
                w: width,
                h: height
            },
            inner: {
                x: bounds.left + border.l,
                y: bounds.top + border.t,
                w: width - border.l - border.r,
                h: height - border.t - border.b
            }
        };
    }

    function inRange(vm, x, y) {
        var skipX = x === null;
        var skipY = y === null;
        var bounds = !vm || (skipX && skipY) ? false : getBarBounds(vm);

        return bounds
            && (skipX || x >= bounds.left && x <= bounds.right)
            && (skipY || y >= bounds.top && y <= bounds.bottom);
    }

    var element_rectangle = core_element.extend({
        draw: function () {
            var ctx = this._chart.ctx;
            var vm = this._view;
            var rects = boundingRects(vm);
            var outer = rects.outer;
            var inner = rects.inner;

            ctx.fillStyle = vm.backgroundColor;
            ctx.fillRect(outer.x, outer.y, outer.w, outer.h);

            if (outer.w === inner.w && outer.h === inner.h) {
                return;
            }

            ctx.save();
            ctx.beginPath();
            ctx.rect(outer.x, outer.y, outer.w, outer.h);
            ctx.clip();
            ctx.fillStyle = vm.borderColor;
            ctx.rect(inner.x, inner.y, inner.w, inner.h);
            ctx.fill('evenodd');
            ctx.restore();
        },

        height: function () {
            var vm = this._view;
            return vm.base - vm.y;
        },

        inRange: function (mouseX, mouseY) {
            return inRange(this._view, mouseX, mouseY);
        },

        inLabelRange: function (mouseX, mouseY) {
            var vm = this._view;
            return isVertical(vm)
                ? inRange(vm, mouseX, null)
                : inRange(vm, null, mouseY);
        },

        inXRange: function (mouseX) {
            return inRange(this._view, mouseX, null);
        },

        inYRange: function (mouseY) {
            return inRange(this._view, null, mouseY);
        },

        getCenterPoint: function () {
            var vm = this._view;
            var x, y;
            if (isVertical(vm)) {
                x = vm.x;
                y = (vm.y + vm.base) / 2;
            } else {
                x = (vm.x + vm.base) / 2;
                y = vm.y;
            }

            return { x: x, y: y };
        },

        getArea: function () {
            var vm = this._view;

            return isVertical(vm)
                ? vm.width * Math.abs(vm.y - vm.base)
                : vm.height * Math.abs(vm.x - vm.base);
        },

        tooltipPosition: function () {
            var vm = this._view;
            return {
                x: vm.x,
                y: vm.y
            };
        }
    });

    var elements = {};
    var Arc = element_arc;
    var Line = element_line;
    var Point = element_point;
    var Rectangle = element_rectangle;
    elements.Arc = Arc;
    elements.Line = Line;
    elements.Point = Point;
    elements.Rectangle = Rectangle;

    var resolve$1 = helpers$1.options.resolve;

    core_defaults._set('bar', {
        hover: {
            mode: 'label'
        },

        scales: {
            xAxes: [{
                type: 'category',
                categoryPercentage: 0.8,
                barPercentage: 0.9,
                offset: true,
                gridLines: {
                    offsetGridLines: true
                }
            }],

            yAxes: [{
                type: 'linear'
            }]
        }
    });

    /**
     * Computes the "optimal" sample size to maintain bars equally sized while preventing overlap.
     * @private
     */
    function computeMinSampleSize(scale, pixels) {
        var min = scale.isHorizontal() ? scale.width : scale.height;
        var ticks = scale.getTicks();
        var prev, curr, i, ilen;

        for (i = 1, ilen = pixels.length; i < ilen; ++i) {
            min = Math.min(min, Math.abs(pixels[i] - pixels[i - 1]));
        }

        for (i = 0, ilen = ticks.length; i < ilen; ++i) {
            curr = scale.getPixelForTick(i);
            min = i > 0 ? Math.min(min, curr - prev) : min;
            prev = curr;
        }

        return min;
    }

    /**
     * Computes an "ideal" category based on the absolute bar thickness or, if undefined or null,
     * uses the smallest interval (see computeMinSampleSize) that prevents bar overlapping. This
     * mode currently always generates bars equally sized (until we introduce scriptable options?).
     * @private
     */
    function computeFitCategoryTraits(index, ruler, options) {
        var thickness = options.barThickness;
        var count = ruler.stackCount;
        var curr = ruler.pixels[index];
        var size, ratio;

        if (helpers$1.isNullOrUndef(thickness)) {
            size = ruler.min * options.categoryPercentage;
            ratio = options.barPercentage;
        } else {
            // When bar thickness is enforced, category and bar percentages are ignored.
            // Note(SB): we could add support for relative bar thickness (e.g. barThickness: '50%')
            // and deprecate barPercentage since this value is ignored when thickness is absolute.
            size = thickness * count;
            ratio = 1;
        }

        return {
            chunk: size / count,
            ratio: ratio,
            start: curr - (size / 2)
        };
    }

    /**
     * Computes an "optimal" category that globally arranges bars side by side (no gap when
     * percentage options are 1), based on the previous and following categories. This mode
     * generates bars with different widths when data are not evenly spaced.
     * @private
     */
    function computeFlexCategoryTraits(index, ruler, options) {
        var pixels = ruler.pixels;
        var curr = pixels[index];
        var prev = index > 0 ? pixels[index - 1] : null;
        var next = index < pixels.length - 1 ? pixels[index + 1] : null;
        var percent = options.categoryPercentage;
        var start, size;

        if (prev === null) {
            // first data: its size is double based on the next point or,
            // if it's also the last data, we use the scale size.
            prev = curr - (next === null ? ruler.end - ruler.start : next - curr);
        }

        if (next === null) {
            // last data: its size is also double based on the previous point.
            next = curr + curr - prev;
        }

        start = curr - (curr - Math.min(prev, next)) / 2 * percent;
        size = Math.abs(next - prev) / 2 * percent;

        return {
            chunk: size / ruler.stackCount,
            ratio: options.barPercentage,
            start: start
        };
    }

    var controller_bar = core_datasetController.extend({

        dataElementType: elements.Rectangle,

        initialize: function () {
            var me = this;
            var meta;

            core_datasetController.prototype.initialize.apply(me, arguments);

            meta = me.getMeta();
            meta.stack = me.getDataset().stack;
            meta.bar = true;
        },

        update: function (reset) {
            var me = this;
            var rects = me.getMeta().data;
            var i, ilen;

            me._ruler = me.getRuler();

            for (i = 0, ilen = rects.length; i < ilen; ++i) {
                me.updateElement(rects[i], i, reset);
            }
        },

        updateElement: function (rectangle, index, reset) {
            var me = this;
            var meta = me.getMeta();
            var dataset = me.getDataset();
            var options = me._resolveElementOptions(rectangle, index);

            rectangle._xScale = me.getScaleForId(meta.xAxisID);
            rectangle._yScale = me.getScaleForId(meta.yAxisID);
            rectangle._datasetIndex = me.index;
            rectangle._index = index;
            rectangle._model = {
                backgroundColor: options.backgroundColor,
                borderColor: options.borderColor,
                borderSkipped: options.borderSkipped,
                borderWidth: options.borderWidth,
                datasetLabel: dataset.label,
                label: me.chart.data.labels[index]
            };

            me._updateElementGeometry(rectangle, index, reset);

            rectangle.pivot();
        },

        /**
         * @private
         */
        _updateElementGeometry: function (rectangle, index, reset) {
            var me = this;
            var model = rectangle._model;
            var vscale = me._getValueScale();
            var base = vscale.getBasePixel();
            var horizontal = vscale.isHorizontal();
            var ruler = me._ruler || me.getRuler();
            var vpixels = me.calculateBarValuePixels(me.index, index);
            var ipixels = me.calculateBarIndexPixels(me.index, index, ruler);

            model.horizontal = horizontal;
            model.base = reset ? base : vpixels.base;
            model.x = horizontal ? reset ? base : vpixels.head : ipixels.center;
            model.y = horizontal ? ipixels.center : reset ? base : vpixels.head;
            model.height = horizontal ? ipixels.size : undefined;
            model.width = horizontal ? undefined : ipixels.size;
        },

        /**
         * Returns the stacks based on groups and bar visibility.
         * @param {number} [last] - The dataset index
         * @returns {string[]} The list of stack IDs
         * @private
         */
        _getStacks: function (last) {
            var me = this;
            var chart = me.chart;
            var scale = me._getIndexScale();
            var stacked = scale.options.stacked;
            var ilen = last === undefined ? chart.data.datasets.length : last + 1;
            var stacks = [];
            var i, meta;

            for (i = 0; i < ilen; ++i) {
                meta = chart.getDatasetMeta(i);
                if (meta.bar && chart.isDatasetVisible(i) &&
                    (stacked === false ||
                        (stacked === true && stacks.indexOf(meta.stack) === -1) ||
                        (stacked === undefined && (meta.stack === undefined || stacks.indexOf(meta.stack) === -1)))) {
                    stacks.push(meta.stack);
                }
            }

            return stacks;
        },

        /**
         * Returns the effective number of stacks based on groups and bar visibility.
         * @private
         */
        getStackCount: function () {
            return this._getStacks().length;
        },

        /**
         * Returns the stack index for the given dataset based on groups and bar visibility.
         * @param {number} [datasetIndex] - The dataset index
         * @param {string} [name] - The stack name to find
         * @returns {number} The stack index
         * @private
         */
        getStackIndex: function (datasetIndex, name) {
            var stacks = this._getStacks(datasetIndex);
            var index = (name !== undefined)
                ? stacks.indexOf(name)
                : -1; // indexOf returns -1 if element is not present

            return (index === -1)
                ? stacks.length - 1
                : index;
        },

        /**
         * @private
         */
        getRuler: function () {
            var me = this;
            var scale = me._getIndexScale();
            var stackCount = me.getStackCount();
            var datasetIndex = me.index;
            var isHorizontal = scale.isHorizontal();
            var start = isHorizontal ? scale.left : scale.top;
            var end = start + (isHorizontal ? scale.width : scale.height);
            var pixels = [];
            var i, ilen, min;

            for (i = 0, ilen = me.getMeta().data.length; i < ilen; ++i) {
                pixels.push(scale.getPixelForValue(null, i, datasetIndex));
            }

            min = helpers$1.isNullOrUndef(scale.options.barThickness)
                ? computeMinSampleSize(scale, pixels)
                : -1;

            return {
                min: min,
                pixels: pixels,
                start: start,
                end: end,
                stackCount: stackCount,
                scale: scale
            };
        },

        /**
         * Note: pixel values are not clamped to the scale area.
         * @private
         */
        calculateBarValuePixels: function (datasetIndex, index) {
            var me = this;
            var chart = me.chart;
            var meta = me.getMeta();
            var scale = me._getValueScale();
            var isHorizontal = scale.isHorizontal();
            var datasets = chart.data.datasets;
            var value = +scale.getRightValue(datasets[datasetIndex].data[index]);
            var minBarLength = scale.options.minBarLength;
            var stacked = scale.options.stacked;
            var stack = meta.stack;
            var start = 0;
            var i, imeta, ivalue, base, head, size;

            if (stacked || (stacked === undefined && stack !== undefined)) {
                for (i = 0; i < datasetIndex; ++i) {
                    imeta = chart.getDatasetMeta(i);

                    if (imeta.bar &&
                        imeta.stack === stack &&
                        imeta.controller._getValueScaleId() === scale.id &&
                        chart.isDatasetVisible(i)) {

                        ivalue = +scale.getRightValue(datasets[i].data[index]);
                        if ((value < 0 && ivalue < 0) || (value >= 0 && ivalue > 0)) {
                            start += ivalue;
                        }
                    }
                }
            }

            base = scale.getPixelForValue(start);
            head = scale.getPixelForValue(start + value);
            size = head - base;

            if (minBarLength !== undefined && Math.abs(size) < minBarLength) {
                size = minBarLength;
                if (value >= 0 && !isHorizontal || value < 0 && isHorizontal) {
                    head = base - minBarLength;
                } else {
                    head = base + minBarLength;
                }
            }

            return {
                size: size,
                base: base,
                head: head,
                center: head + size / 2
            };
        },

        /**
         * @private
         */
        calculateBarIndexPixels: function (datasetIndex, index, ruler) {
            var me = this;
            var options = ruler.scale.options;
            var range = options.barThickness === 'flex'
                ? computeFlexCategoryTraits(index, ruler, options)
                : computeFitCategoryTraits(index, ruler, options);

            var stackIndex = me.getStackIndex(datasetIndex, me.getMeta().stack);
            var center = range.start + (range.chunk * stackIndex) + (range.chunk / 2);
            var size = Math.min(
                helpers$1.valueOrDefault(options.maxBarThickness, Infinity),
                range.chunk * range.ratio);

            return {
                base: center - size / 2,
                head: center + size / 2,
                center: center,
                size: size
            };
        },

        draw: function () {
            var me = this;
            var chart = me.chart;
            var scale = me._getValueScale();
            var rects = me.getMeta().data;
            var dataset = me.getDataset();
            var ilen = rects.length;
            var i = 0;

            helpers$1.canvas.clipArea(chart.ctx, chart.chartArea);

            for (; i < ilen; ++i) {
                if (!isNaN(scale.getRightValue(dataset.data[i]))) {
                    rects[i].draw();
                }
            }

            helpers$1.canvas.unclipArea(chart.ctx);
        },

        /**
         * @private
         */
        _resolveElementOptions: function (rectangle, index) {
            var me = this;
            var chart = me.chart;
            var datasets = chart.data.datasets;
            var dataset = datasets[me.index];
            var custom = rectangle.custom || {};
            var options = chart.options.elements.rectangle;
            var values = {};
            var i, ilen, key;

            // Scriptable options
            var context = {
                chart: chart,
                dataIndex: index,
                dataset: dataset,
                datasetIndex: me.index
            };

            var keys = [
                'backgroundColor',
                'borderColor',
                'borderSkipped',
                'borderWidth'
            ];

            for (i = 0, ilen = keys.length; i < ilen; ++i) {
                key = keys[i];
                values[key] = resolve$1([
                    custom[key],
                    dataset[key],
                    options[key]
                ], context, index);
            }

            return values;
        }
    });

    var valueOrDefault$3 = helpers$1.valueOrDefault;
    var resolve$2 = helpers$1.options.resolve;

    core_defaults._set('bubble', {
        hover: {
            mode: 'single'
        },

        scales: {
            xAxes: [{
                type: 'linear', // bubble should probably use a linear scale by default
                position: 'bottom',
                id: 'x-axis-0' // need an ID so datasets can reference the scale
            }],
            yAxes: [{
                type: 'linear',
                position: 'left',
                id: 'y-axis-0'
            }]
        },

        tooltips: {
            callbacks: {
                title: function () {
                    // Title doesn't make sense for scatter since we format the data as a point
                    return '';
                },
                label: function (item, data) {
                    var datasetLabel = data.datasets[item.datasetIndex].label || '';
                    var dataPoint = data.datasets[item.datasetIndex].data[item.index];
                    return datasetLabel + ': (' + item.xLabel + ', ' + item.yLabel + ', ' + dataPoint.r + ')';
                }
            }
        }
    });

    var controller_bubble = core_datasetController.extend({
        /**
         * @protected
         */
        dataElementType: elements.Point,

        /**
         * @protected
         */
        update: function (reset) {
            var me = this;
            var meta = me.getMeta();
            var points = meta.data;

            // Update Points
            helpers$1.each(points, function (point, index) {
                me.updateElement(point, index, reset);
            });
        },

        /**
         * @protected
         */
        updateElement: function (point, index, reset) {
            var me = this;
            var meta = me.getMeta();
            var custom = point.custom || {};
            var xScale = me.getScaleForId(meta.xAxisID);
            var yScale = me.getScaleForId(meta.yAxisID);
            var options = me._resolveElementOptions(point, index);
            var data = me.getDataset().data[index];
            var dsIndex = me.index;

            var x = reset ? xScale.getPixelForDecimal(0.5) : xScale.getPixelForValue(typeof data === 'object' ? data : NaN, index, dsIndex);
            var y = reset ? yScale.getBasePixel() : yScale.getPixelForValue(data, index, dsIndex);

            point._xScale = xScale;
            point._yScale = yScale;
            point._options = options;
            point._datasetIndex = dsIndex;
            point._index = index;
            point._model = {
                backgroundColor: options.backgroundColor,
                borderColor: options.borderColor,
                borderWidth: options.borderWidth,
                hitRadius: options.hitRadius,
                pointStyle: options.pointStyle,
                rotation: options.rotation,
                radius: reset ? 0 : options.radius,
                skip: custom.skip || isNaN(x) || isNaN(y),
                x: x,
                y: y,
            };

            point.pivot();
        },

        /**
         * @protected
         */
        setHoverStyle: function (point) {
            var model = point._model;
            var options = point._options;
            var getHoverColor = helpers$1.getHoverColor;

            point.$previousStyle = {
                backgroundColor: model.backgroundColor,
                borderColor: model.borderColor,
                borderWidth: model.borderWidth,
                radius: model.radius
            };

            model.backgroundColor = valueOrDefault$3(options.hoverBackgroundColor, getHoverColor(options.backgroundColor));
            model.borderColor = valueOrDefault$3(options.hoverBorderColor, getHoverColor(options.borderColor));
            model.borderWidth = valueOrDefault$3(options.hoverBorderWidth, options.borderWidth);
            model.radius = options.radius + options.hoverRadius;
        },

        /**
         * @private
         */
        _resolveElementOptions: function (point, index) {
            var me = this;
            var chart = me.chart;
            var datasets = chart.data.datasets;
            var dataset = datasets[me.index];
            var custom = point.custom || {};
            var options = chart.options.elements.point;
            var data = dataset.data[index];
            var values = {};
            var i, ilen, key;

            // Scriptable options
            var context = {
                chart: chart,
                dataIndex: index,
                dataset: dataset,
                datasetIndex: me.index
            };

            var keys = [
                'backgroundColor',
                'borderColor',
                'borderWidth',
                'hoverBackgroundColor',
                'hoverBorderColor',
                'hoverBorderWidth',
                'hoverRadius',
                'hitRadius',
                'pointStyle',
                'rotation'
            ];

            for (i = 0, ilen = keys.length; i < ilen; ++i) {
                key = keys[i];
                values[key] = resolve$2([
                    custom[key],
                    dataset[key],
                    options[key]
                ], context, index);
            }

            // Custom radius resolution
            values.radius = resolve$2([
                custom.radius,
                data ? data.r : undefined,
                dataset.radius,
                options.radius
            ], context, index);

            return values;
        }
    });

    var resolve$3 = helpers$1.options.resolve;
    var valueOrDefault$4 = helpers$1.valueOrDefault;

    core_defaults._set('doughnut', {
        animation: {
            // Boolean - Whether we animate the rotation of the Doughnut
            animateRotate: true,
            // Boolean - Whether we animate scaling the Doughnut from the centre
            animateScale: false
        },
        hover: {
            mode: 'single'
        },
        legendCallback: function (chart) {
            var text = [];
            text.push('<ul class="' + chart.id + '-legend">');

            var data = chart.data;
            var datasets = data.datasets;
            var labels = data.labels;

            if (datasets.length) {
                for (var i = 0; i < datasets[0].data.length; ++i) {
                    text.push('<li><span style="background-color:' + datasets[0].backgroundColor[i] + '"></span>');
                    if (labels[i]) {
                        text.push(labels[i]);
                    }
                    text.push('</li>');
                }
            }

            text.push('</ul>');
            return text.join('');
        },
        legend: {
            labels: {
                generateLabels: function (chart) {
                    var data = chart.data;
                    if (data.labels.length && data.datasets.length) {
                        return data.labels.map(function (label, i) {
                            var meta = chart.getDatasetMeta(0);
                            var ds = data.datasets[0];
                            var arc = meta.data[i];
                            var custom = arc && arc.custom || {};
                            var arcOpts = chart.options.elements.arc;
                            var fill = resolve$3([custom.backgroundColor, ds.backgroundColor, arcOpts.backgroundColor], undefined, i);
                            var stroke = resolve$3([custom.borderColor, ds.borderColor, arcOpts.borderColor], undefined, i);
                            var bw = resolve$3([custom.borderWidth, ds.borderWidth, arcOpts.borderWidth], undefined, i);

                            return {
                                text: label,
                                fillStyle: fill,
                                strokeStyle: stroke,
                                lineWidth: bw,
                                hidden: isNaN(ds.data[i]) || meta.data[i].hidden,

                                // Extra data used for toggling the correct item
                                index: i
                            };
                        });
                    }
                    return [];
                }
            },

            onClick: function (e, legendItem) {
                var index = legendItem.index;
                var chart = this.chart;
                var i, ilen, meta;

                for (i = 0, ilen = (chart.data.datasets || []).length; i < ilen; ++i) {
                    meta = chart.getDatasetMeta(i);
                    // toggle visibility of index if exists
                    if (meta.data[index]) {
                        meta.data[index].hidden = !meta.data[index].hidden;
                    }
                }

                chart.update();
            }
        },

        // The percentage of the chart that we cut out of the middle.
        cutoutPercentage: 50,

        // The rotation of the chart, where the first data arc begins.
        rotation: Math.PI * -0.5,

        // The total circumference of the chart.
        circumference: Math.PI * 2.0,

        // Need to override these to give a nice default
        tooltips: {
            callbacks: {
                title: function () {
                    return '';
                },
                label: function (tooltipItem, data) {
                    var dataLabel = data.labels[tooltipItem.index];
                    var value = ': ' + data.datasets[tooltipItem.datasetIndex].data[tooltipItem.index];

                    if (helpers$1.isArray(dataLabel)) {
                        // show value on first line of multiline label
                        // need to clone because we are changing the value
                        dataLabel = dataLabel.slice();
                        dataLabel[0] += value;
                    } else {
                        dataLabel += value;
                    }

                    return dataLabel;
                }
            }
        }
    });

    var controller_doughnut = core_datasetController.extend({

        dataElementType: elements.Arc,

        linkScales: helpers$1.noop,

        // Get index of the dataset in relation to the visible datasets. This allows determining the inner and outer radius correctly
        getRingIndex: function (datasetIndex) {
            var ringIndex = 0;

            for (var j = 0; j < datasetIndex; ++j) {
                if (this.chart.isDatasetVisible(j)) {
                    ++ringIndex;
                }
            }

            return ringIndex;
        },

        update: function (reset) {
            var me = this;
            var chart = me.chart;
            var chartArea = chart.chartArea;
            var opts = chart.options;
            var availableWidth = chartArea.right - chartArea.left;
            var availableHeight = chartArea.bottom - chartArea.top;
            var minSize = Math.min(availableWidth, availableHeight);
            var offset = { x: 0, y: 0 };
            var meta = me.getMeta();
            var arcs = meta.data;
            var cutoutPercentage = opts.cutoutPercentage;
            var circumference = opts.circumference;
            var chartWeight = me._getRingWeight(me.index);
            var i, ilen;

            // If the chart's circumference isn't a full circle, calculate minSize as a ratio of the width/height of the arc
            if (circumference < Math.PI * 2.0) {
                var startAngle = opts.rotation % (Math.PI * 2.0);
                startAngle += Math.PI * 2.0 * (startAngle >= Math.PI ? -1 : startAngle < -Math.PI ? 1 : 0);
                var endAngle = startAngle + circumference;
                var start = { x: Math.cos(startAngle), y: Math.sin(startAngle) };
                var end = { x: Math.cos(endAngle), y: Math.sin(endAngle) };
                var contains0 = (startAngle <= 0 && endAngle >= 0) || (startAngle <= Math.PI * 2.0 && Math.PI * 2.0 <= endAngle);
                var contains90 = (startAngle <= Math.PI * 0.5 && Math.PI * 0.5 <= endAngle) || (startAngle <= Math.PI * 2.5 && Math.PI * 2.5 <= endAngle);
                var contains180 = (startAngle <= -Math.PI && -Math.PI <= endAngle) || (startAngle <= Math.PI && Math.PI <= endAngle);
                var contains270 = (startAngle <= -Math.PI * 0.5 && -Math.PI * 0.5 <= endAngle) || (startAngle <= Math.PI * 1.5 && Math.PI * 1.5 <= endAngle);
                var cutout = cutoutPercentage / 100.0;
                var min = { x: contains180 ? -1 : Math.min(start.x * (start.x < 0 ? 1 : cutout), end.x * (end.x < 0 ? 1 : cutout)), y: contains270 ? -1 : Math.min(start.y * (start.y < 0 ? 1 : cutout), end.y * (end.y < 0 ? 1 : cutout)) };
                var max = { x: contains0 ? 1 : Math.max(start.x * (start.x > 0 ? 1 : cutout), end.x * (end.x > 0 ? 1 : cutout)), y: contains90 ? 1 : Math.max(start.y * (start.y > 0 ? 1 : cutout), end.y * (end.y > 0 ? 1 : cutout)) };
                var size = { width: (max.x - min.x) * 0.5, height: (max.y - min.y) * 0.5 };
                minSize = Math.min(availableWidth / size.width, availableHeight / size.height);
                offset = { x: (max.x + min.x) * -0.5, y: (max.y + min.y) * -0.5 };
            }

            for (i = 0, ilen = arcs.length; i < ilen; ++i) {
                arcs[i]._options = me._resolveElementOptions(arcs[i], i);
            }

            chart.borderWidth = me.getMaxBorderWidth();
            chart.outerRadius = Math.max((minSize - chart.borderWidth) / 2, 0);
            chart.innerRadius = Math.max(cutoutPercentage ? (chart.outerRadius / 100) * (cutoutPercentage) : 0, 0);
            chart.radiusLength = (chart.outerRadius - chart.innerRadius) / (me._getVisibleDatasetWeightTotal() || 1);
            chart.offsetX = offset.x * chart.outerRadius;
            chart.offsetY = offset.y * chart.outerRadius;

            meta.total = me.calculateTotal();

            me.outerRadius = chart.outerRadius - chart.radiusLength * me._getRingWeightOffset(me.index);
            me.innerRadius = Math.max(me.outerRadius - chart.radiusLength * chartWeight, 0);

            for (i = 0, ilen = arcs.length; i < ilen; ++i) {
                me.updateElement(arcs[i], i, reset);
            }
        },

        updateElement: function (arc, index, reset) {
            var me = this;
            var chart = me.chart;
            var chartArea = chart.chartArea;
            var opts = chart.options;
            var animationOpts = opts.animation;
            var centerX = (chartArea.left + chartArea.right) / 2;
            var centerY = (chartArea.top + chartArea.bottom) / 2;
            var startAngle = opts.rotation; // non reset case handled later
            var endAngle = opts.rotation; // non reset case handled later
            var dataset = me.getDataset();
            var circumference = reset && animationOpts.animateRotate ? 0 : arc.hidden ? 0 : me.calculateCircumference(dataset.data[index]) * (opts.circumference / (2.0 * Math.PI));
            var innerRadius = reset && animationOpts.animateScale ? 0 : me.innerRadius;
            var outerRadius = reset && animationOpts.animateScale ? 0 : me.outerRadius;
            var options = arc._options || {};

            helpers$1.extend(arc, {
                // Utility
                _datasetIndex: me.index,
                _index: index,

                // Desired view properties
                _model: {
                    backgroundColor: options.backgroundColor,
                    borderColor: options.borderColor,
                    borderWidth: options.borderWidth,
                    borderAlign: options.borderAlign,
                    x: centerX + chart.offsetX,
                    y: centerY + chart.offsetY,
                    startAngle: startAngle,
                    endAngle: endAngle,
                    circumference: circumference,
                    outerRadius: outerRadius,
                    innerRadius: innerRadius,
                    label: helpers$1.valueAtIndexOrDefault(dataset.label, index, chart.data.labels[index])
                }
            });

            var model = arc._model;

            // Set correct angles if not resetting
            if (!reset || !animationOpts.animateRotate) {
                if (index === 0) {
                    model.startAngle = opts.rotation;
                } else {
                    model.startAngle = me.getMeta().data[index - 1]._model.endAngle;
                }

                model.endAngle = model.startAngle + model.circumference;
            }

            arc.pivot();
        },

        calculateTotal: function () {
            var dataset = this.getDataset();
            var meta = this.getMeta();
            var total = 0;
            var value;

            helpers$1.each(meta.data, function (element, index) {
                value = dataset.data[index];
                if (!isNaN(value) && !element.hidden) {
                    total += Math.abs(value);
                }
            });

            /* if (total === 0) {
                total = NaN;
            }*/

            return total;
        },

        calculateCircumference: function (value) {
            var total = this.getMeta().total;
            if (total > 0 && !isNaN(value)) {
                return (Math.PI * 2.0) * (Math.abs(value) / total);
            }
            return 0;
        },

        // gets the max border or hover width to properly scale pie charts
        getMaxBorderWidth: function (arcs) {
            var me = this;
            var max = 0;
            var chart = me.chart;
            var i, ilen, meta, arc, controller, options, borderWidth, hoverWidth;

            if (!arcs) {
                // Find the outmost visible dataset
                for (i = 0, ilen = chart.data.datasets.length; i < ilen; ++i) {
                    if (chart.isDatasetVisible(i)) {
                        meta = chart.getDatasetMeta(i);
                        arcs = meta.data;
                        if (i !== me.index) {
                            controller = meta.controller;
                        }
                        break;
                    }
                }
            }

            if (!arcs) {
                return 0;
            }

            for (i = 0, ilen = arcs.length; i < ilen; ++i) {
                arc = arcs[i];
                options = controller ? controller._resolveElementOptions(arc, i) : arc._options;
                if (options.borderAlign !== 'inner') {
                    borderWidth = options.borderWidth;
                    hoverWidth = options.hoverBorderWidth;

                    max = borderWidth > max ? borderWidth : max;
                    max = hoverWidth > max ? hoverWidth : max;
                }
            }
            return max;
        },

        /**
         * @protected
         */
        setHoverStyle: function (arc) {
            var model = arc._model;
            var options = arc._options;
            var getHoverColor = helpers$1.getHoverColor;

            arc.$previousStyle = {
                backgroundColor: model.backgroundColor,
                borderColor: model.borderColor,
                borderWidth: model.borderWidth,
            };

            model.backgroundColor = valueOrDefault$4(options.hoverBackgroundColor, getHoverColor(options.backgroundColor));
            model.borderColor = valueOrDefault$4(options.hoverBorderColor, getHoverColor(options.borderColor));
            model.borderWidth = valueOrDefault$4(options.hoverBorderWidth, options.borderWidth);
        },

        /**
         * @private
         */
        _resolveElementOptions: function (arc, index) {
            var me = this;
            var chart = me.chart;
            var dataset = me.getDataset();
            var custom = arc.custom || {};
            var options = chart.options.elements.arc;
            var values = {};
            var i, ilen, key;

            // Scriptable options
            var context = {
                chart: chart,
                dataIndex: index,
                dataset: dataset,
                datasetIndex: me.index
            };

            var keys = [
                'backgroundColor',
                'borderColor',
                'borderWidth',
                'borderAlign',
                'hoverBackgroundColor',
                'hoverBorderColor',
                'hoverBorderWidth',
            ];

            for (i = 0, ilen = keys.length; i < ilen; ++i) {
                key = keys[i];
                values[key] = resolve$3([
                    custom[key],
                    dataset[key],
                    options[key]
                ], context, index);
            }

            return values;
        },

        /**
         * Get radius length offset of the dataset in relation to the visible datasets weights. This allows determining the inner and outer radius correctly
         * @private
         */
        _getRingWeightOffset: function (datasetIndex) {
            var ringWeightOffset = 0;

            for (var i = 0; i < datasetIndex; ++i) {
                if (this.chart.isDatasetVisible(i)) {
                    ringWeightOffset += this._getRingWeight(i);
                }
            }

            return ringWeightOffset;
        },

        /**
         * @private
         */
        _getRingWeight: function (dataSetIndex) {
            return Math.max(valueOrDefault$4(this.chart.data.datasets[dataSetIndex].weight, 1), 0);
        },

        /**
         * Returns the sum of all visibile data set weights.  This value can be 0.
         * @private
         */
        _getVisibleDatasetWeightTotal: function () {
            return this._getRingWeightOffset(this.chart.data.datasets.length);
        }
    });

    core_defaults._set('horizontalBar', {
        hover: {
            mode: 'index',
            axis: 'y'
        },

        scales: {
            xAxes: [{
                type: 'linear',
                position: 'bottom'
            }],

            yAxes: [{
                type: 'category',
                position: 'left',
                categoryPercentage: 0.8,
                barPercentage: 0.9,
                offset: true,
                gridLines: {
                    offsetGridLines: true
                }
            }]
        },

        elements: {
            rectangle: {
                borderSkipped: 'left'
            }
        },

        tooltips: {
            mode: 'index',
            axis: 'y'
        }
    });

    var controller_horizontalBar = controller_bar.extend({
        /**
         * @private
         */
        _getValueScaleId: function () {
            return this.getMeta().xAxisID;
        },

        /**
         * @private
         */
        _getIndexScaleId: function () {
            return this.getMeta().yAxisID;
        }
    });

    var valueOrDefault$5 = helpers$1.valueOrDefault;
    var resolve$4 = helpers$1.options.resolve;
    var isPointInArea = helpers$1.canvas._isPointInArea;

    core_defaults._set('line', {
        showLines: true,
        spanGaps: false,

        hover: {
            mode: 'label'
        },

        scales: {
            xAxes: [{
                type: 'category',
                id: 'x-axis-0'
            }],
            yAxes: [{
                type: 'linear',
                id: 'y-axis-0'
            }]
        }
    });

    function lineEnabled(dataset, options) {
        return valueOrDefault$5(dataset.showLine, options.showLines);
    }

    var controller_line = core_datasetController.extend({

        datasetElementType: elements.Line,

        dataElementType: elements.Point,

        update: function (reset) {
            var me = this;
            var meta = me.getMeta();
            var line = meta.dataset;
            var points = meta.data || [];
            var scale = me.getScaleForId(meta.yAxisID);
            var dataset = me.getDataset();
            var showLine = lineEnabled(dataset, me.chart.options);
            var i, ilen;

            // Update Line
            if (showLine) {
                // Compatibility: If the properties are defined with only the old name, use those values
                if ((dataset.tension !== undefined) && (dataset.lineTension === undefined)) {
                    dataset.lineTension = dataset.tension;
                }

                // Utility
                line._scale = scale;
                line._datasetIndex = me.index;
                // Data
                line._children = points;
                // Model
                line._model = me._resolveLineOptions(line);

                line.pivot();
            }

            // Update Points
            for (i = 0, ilen = points.length; i < ilen; ++i) {
                me.updateElement(points[i], i, reset);
            }

            if (showLine && line._model.tension !== 0) {
                me.updateBezierControlPoints();
            }

            // Now pivot the point for animation
            for (i = 0, ilen = points.length; i < ilen; ++i) {
                points[i].pivot();
            }
        },

        updateElement: function (point, index, reset) {
            var me = this;
            var meta = me.getMeta();
            var custom = point.custom || {};
            var dataset = me.getDataset();
            var datasetIndex = me.index;
            var value = dataset.data[index];
            var yScale = me.getScaleForId(meta.yAxisID);
            var xScale = me.getScaleForId(meta.xAxisID);
            var lineModel = meta.dataset._model;
            var x, y;

            var options = me._resolvePointOptions(point, index);

            x = xScale.getPixelForValue(typeof value === 'object' ? value : NaN, index, datasetIndex);
            y = reset ? yScale.getBasePixel() : me.calculatePointY(value, index, datasetIndex);

            // Utility
            point._xScale = xScale;
            point._yScale = yScale;
            point._options = options;
            point._datasetIndex = datasetIndex;
            point._index = index;

            // Desired view properties
            point._model = {
                x: x,
                y: y,
                skip: custom.skip || isNaN(x) || isNaN(y),
                // Appearance
                radius: options.radius,
                pointStyle: options.pointStyle,
                rotation: options.rotation,
                backgroundColor: options.backgroundColor,
                borderColor: options.borderColor,
                borderWidth: options.borderWidth,
                tension: valueOrDefault$5(custom.tension, lineModel ? lineModel.tension : 0),
                steppedLine: lineModel ? lineModel.steppedLine : false,
                // Tooltip
                hitRadius: options.hitRadius
            };
        },

        /**
         * @private
         */
        _resolvePointOptions: function (element, index) {
            var me = this;
            var chart = me.chart;
            var dataset = chart.data.datasets[me.index];
            var custom = element.custom || {};
            var options = chart.options.elements.point;
            var values = {};
            var i, ilen, key;

            // Scriptable options
            var context = {
                chart: chart,
                dataIndex: index,
                dataset: dataset,
                datasetIndex: me.index
            };

            var ELEMENT_OPTIONS = {
                backgroundColor: 'pointBackgroundColor',
                borderColor: 'pointBorderColor',
                borderWidth: 'pointBorderWidth',
                hitRadius: 'pointHitRadius',
                hoverBackgroundColor: 'pointHoverBackgroundColor',
                hoverBorderColor: 'pointHoverBorderColor',
                hoverBorderWidth: 'pointHoverBorderWidth',
                hoverRadius: 'pointHoverRadius',
                pointStyle: 'pointStyle',
                radius: 'pointRadius',
                rotation: 'pointRotation'
            };
            var keys = Object.keys(ELEMENT_OPTIONS);

            for (i = 0, ilen = keys.length; i < ilen; ++i) {
                key = keys[i];
                values[key] = resolve$4([
                    custom[key],
                    dataset[ELEMENT_OPTIONS[key]],
                    dataset[key],
                    options[key]
                ], context, index);
            }

            return values;
        },

        /**
         * @private
         */
        _resolveLineOptions: function (element) {
            var me = this;
            var chart = me.chart;
            var dataset = chart.data.datasets[me.index];
            var custom = element.custom || {};
            var options = chart.options;
            var elementOptions = options.elements.line;
            var values = {};
            var i, ilen, key;

            var keys = [
                'backgroundColor',
                'borderWidth',
                'borderColor',
                'borderCapStyle',
                'borderDash',
                'borderDashOffset',
                'borderJoinStyle',
                'fill',
                'cubicInterpolationMode'
            ];

            for (i = 0, ilen = keys.length; i < ilen; ++i) {
                key = keys[i];
                values[key] = resolve$4([
                    custom[key],
                    dataset[key],
                    elementOptions[key]
                ]);
            }

            // The default behavior of lines is to break at null values, according
            // to https://github.com/chartjs/Chart.js/issues/2435#issuecomment-216718158
            // This option gives lines the ability to span gaps
            values.spanGaps = valueOrDefault$5(dataset.spanGaps, options.spanGaps);
            values.tension = valueOrDefault$5(dataset.lineTension, elementOptions.tension);
            values.steppedLine = resolve$4([custom.steppedLine, dataset.steppedLine, elementOptions.stepped]);

            return values;
        },

        calculatePointY: function (value, index, datasetIndex) {
            var me = this;
            var chart = me.chart;
            var meta = me.getMeta();
            var yScale = me.getScaleForId(meta.yAxisID);
            var sumPos = 0;
            var sumNeg = 0;
            var i, ds, dsMeta;

            if (yScale.options.stacked) {
                for (i = 0; i < datasetIndex; i++) {
                    ds = chart.data.datasets[i];
                    dsMeta = chart.getDatasetMeta(i);
                    if (dsMeta.type === 'line' && dsMeta.yAxisID === yScale.id && chart.isDatasetVisible(i)) {
                        var stackedRightValue = Number(yScale.getRightValue(ds.data[index]));
                        if (stackedRightValue < 0) {
                            sumNeg += stackedRightValue || 0;
                        } else {
                            sumPos += stackedRightValue || 0;
                        }
                    }
                }

                var rightValue = Number(yScale.getRightValue(value));
                if (rightValue < 0) {
                    return yScale.getPixelForValue(sumNeg + rightValue);
                }
                return yScale.getPixelForValue(sumPos + rightValue);
            }

            return yScale.getPixelForValue(value);
        },

        updateBezierControlPoints: function () {
            var me = this;
            var chart = me.chart;
            var meta = me.getMeta();
            var lineModel = meta.dataset._model;
            var area = chart.chartArea;
            var points = meta.data || [];
            var i, ilen, model, controlPoints;

            // Only consider points that are drawn in case the spanGaps option is used
            if (lineModel.spanGaps) {
                points = points.filter(function (pt) {
                    return !pt._model.skip;
                });
            }

            function capControlPoint(pt, min, max) {
                return Math.max(Math.min(pt, max), min);
            }

            if (lineModel.cubicInterpolationMode === 'monotone') {
                helpers$1.splineCurveMonotone(points);
            } else {
                for (i = 0, ilen = points.length; i < ilen; ++i) {
                    model = points[i]._model;
                    controlPoints = helpers$1.splineCurve(
                        helpers$1.previousItem(points, i)._model,
                        model,
                        helpers$1.nextItem(points, i)._model,
                        lineModel.tension
                    );
                    model.controlPointPreviousX = controlPoints.previous.x;
                    model.controlPointPreviousY = controlPoints.previous.y;
                    model.controlPointNextX = controlPoints.next.x;
                    model.controlPointNextY = controlPoints.next.y;
                }
            }

            if (chart.options.elements.line.capBezierPoints) {
                for (i = 0, ilen = points.length; i < ilen; ++i) {
                    model = points[i]._model;
                    if (isPointInArea(model, area)) {
                        if (i > 0 && isPointInArea(points[i - 1]._model, area)) {
                            model.controlPointPreviousX = capControlPoint(model.controlPointPreviousX, area.left, area.right);
                            model.controlPointPreviousY = capControlPoint(model.controlPointPreviousY, area.top, area.bottom);
                        }
                        if (i < points.length - 1 && isPointInArea(points[i + 1]._model, area)) {
                            model.controlPointNextX = capControlPoint(model.controlPointNextX, area.left, area.right);
                            model.controlPointNextY = capControlPoint(model.controlPointNextY, area.top, area.bottom);
                        }
                    }
                }
            }
        },

        draw: function () {
            var me = this;
            var chart = me.chart;
            var meta = me.getMeta();
            var points = meta.data || [];
            var area = chart.chartArea;
            var ilen = points.length;
            var halfBorderWidth;
            var i = 0;

            if (lineEnabled(me.getDataset(), chart.options)) {
                halfBorderWidth = (meta.dataset._model.borderWidth || 0) / 2;

                helpers$1.canvas.clipArea(chart.ctx, {
                    left: area.left,
                    right: area.right,
                    top: area.top - halfBorderWidth,
                    bottom: area.bottom + halfBorderWidth
                });

                meta.dataset.draw();

                helpers$1.canvas.unclipArea(chart.ctx);
            }

            // Draw the points
            for (; i < ilen; ++i) {
                points[i].draw(area);
            }
        },

        /**
         * @protected
         */
        setHoverStyle: function (point) {
            var model = point._model;
            var options = point._options;
            var getHoverColor = helpers$1.getHoverColor;

            point.$previousStyle = {
                backgroundColor: model.backgroundColor,
                borderColor: model.borderColor,
                borderWidth: model.borderWidth,
                radius: model.radius
            };

            model.backgroundColor = valueOrDefault$5(options.hoverBackgroundColor, getHoverColor(options.backgroundColor));
            model.borderColor = valueOrDefault$5(options.hoverBorderColor, getHoverColor(options.borderColor));
            model.borderWidth = valueOrDefault$5(options.hoverBorderWidth, options.borderWidth);
            model.radius = valueOrDefault$5(options.hoverRadius, options.radius);
        },
    });

    var resolve$5 = helpers$1.options.resolve;

    core_defaults._set('polarArea', {
        scale: {
            type: 'radialLinear',
            angleLines: {
                display: false
            },
            gridLines: {
                circular: true
            },
            pointLabels: {
                display: false
            },
            ticks: {
                beginAtZero: true
            }
        },

        // Boolean - Whether to animate the rotation of the chart
        animation: {
            animateRotate: true,
            animateScale: true
        },

        startAngle: -0.5 * Math.PI,
        legendCallback: function (chart) {
            var text = [];
            text.push('<ul class="' + chart.id + '-legend">');

            var data = chart.data;
            var datasets = data.datasets;
            var labels = data.labels;

            if (datasets.length) {
                for (var i = 0; i < datasets[0].data.length; ++i) {
                    text.push('<li><span style="background-color:' + datasets[0].backgroundColor[i] + '"></span>');
                    if (labels[i]) {
                        text.push(labels[i]);
                    }
                    text.push('</li>');
                }
            }

            text.push('</ul>');
            return text.join('');
        },
        legend: {
            labels: {
                generateLabels: function (chart) {
                    var data = chart.data;
                    if (data.labels.length && data.datasets.length) {
                        return data.labels.map(function (label, i) {
                            var meta = chart.getDatasetMeta(0);
                            var ds = data.datasets[0];
                            var arc = meta.data[i];
                            var custom = arc.custom || {};
                            var arcOpts = chart.options.elements.arc;
                            var fill = resolve$5([custom.backgroundColor, ds.backgroundColor, arcOpts.backgroundColor], undefined, i);
                            var stroke = resolve$5([custom.borderColor, ds.borderColor, arcOpts.borderColor], undefined, i);
                            var bw = resolve$5([custom.borderWidth, ds.borderWidth, arcOpts.borderWidth], undefined, i);

                            return {
                                text: label,
                                fillStyle: fill,
                                strokeStyle: stroke,
                                lineWidth: bw,
                                hidden: isNaN(ds.data[i]) || meta.data[i].hidden,

                                // Extra data used for toggling the correct item
                                index: i
                            };
                        });
                    }
                    return [];
                }
            },

            onClick: function (e, legendItem) {
                var index = legendItem.index;
                var chart = this.chart;
                var i, ilen, meta;

                for (i = 0, ilen = (chart.data.datasets || []).length; i < ilen; ++i) {
                    meta = chart.getDatasetMeta(i);
                    meta.data[index].hidden = !meta.data[index].hidden;
                }

                chart.update();
            }
        },

        // Need to override these to give a nice default
        tooltips: {
            callbacks: {
                title: function () {
                    return '';
                },
                label: function (item, data) {
                    return data.labels[item.index] + ': ' + item.yLabel;
                }
            }
        }
    });

    var controller_polarArea = core_datasetController.extend({

        dataElementType: elements.Arc,

        linkScales: helpers$1.noop,

        update: function (reset) {
            var me = this;
            var dataset = me.getDataset();
            var meta = me.getMeta();
            var start = me.chart.options.startAngle || 0;
            var starts = me._starts = [];
            var angles = me._angles = [];
            var arcs = meta.data;
            var i, ilen, angle;

            me._updateRadius();

            meta.count = me.countVisibleElements();

            for (i = 0, ilen = dataset.data.length; i < ilen; i++) {
                starts[i] = start;
                angle = me._computeAngle(i);
                angles[i] = angle;
                start += angle;
            }

            for (i = 0, ilen = arcs.length; i < ilen; ++i) {
                arcs[i]._options = me._resolveElementOptions(arcs[i], i);
                me.updateElement(arcs[i], i, reset);
            }
        },

        /**
         * @private
         */
        _updateRadius: function () {
            var me = this;
            var chart = me.chart;
            var chartArea = chart.chartArea;
            var opts = chart.options;
            var minSize = Math.min(chartArea.right - chartArea.left, chartArea.bottom - chartArea.top);

            chart.outerRadius = Math.max(minSize / 2, 0);
            chart.innerRadius = Math.max(opts.cutoutPercentage ? (chart.outerRadius / 100) * (opts.cutoutPercentage) : 1, 0);
            chart.radiusLength = (chart.outerRadius - chart.innerRadius) / chart.getVisibleDatasetCount();

            me.outerRadius = chart.outerRadius - (chart.radiusLength * me.index);
            me.innerRadius = me.outerRadius - chart.radiusLength;
        },

        updateElement: function (arc, index, reset) {
            var me = this;
            var chart = me.chart;
            var dataset = me.getDataset();
            var opts = chart.options;
            var animationOpts = opts.animation;
            var scale = chart.scale;
            var labels = chart.data.labels;

            var centerX = scale.xCenter;
            var centerY = scale.yCenter;

            // var negHalfPI = -0.5 * Math.PI;
            var datasetStartAngle = opts.startAngle;
            var distance = arc.hidden ? 0 : scale.getDistanceFromCenterForValue(dataset.data[index]);
            var startAngle = me._starts[index];
            var endAngle = startAngle + (arc.hidden ? 0 : me._angles[index]);

            var resetRadius = animationOpts.animateScale ? 0 : scale.getDistanceFromCenterForValue(dataset.data[index]);
            var options = arc._options || {};

            helpers$1.extend(arc, {
                // Utility
                _datasetIndex: me.index,
                _index: index,
                _scale: scale,

                // Desired view properties
                _model: {
                    backgroundColor: options.backgroundColor,
                    borderColor: options.borderColor,
                    borderWidth: options.borderWidth,
                    borderAlign: options.borderAlign,
                    x: centerX,
                    y: centerY,
                    innerRadius: 0,
                    outerRadius: reset ? resetRadius : distance,
                    startAngle: reset && animationOpts.animateRotate ? datasetStartAngle : startAngle,
                    endAngle: reset && animationOpts.animateRotate ? datasetStartAngle : endAngle,
                    label: helpers$1.valueAtIndexOrDefault(labels, index, labels[index])
                }
            });

            arc.pivot();
        },

        countVisibleElements: function () {
            var dataset = this.getDataset();
            var meta = this.getMeta();
            var count = 0;

            helpers$1.each(meta.data, function (element, index) {
                if (!isNaN(dataset.data[index]) && !element.hidden) {
                    count++;
                }
            });

            return count;
        },

        /**
         * @protected
         */
        setHoverStyle: function (arc) {
            var model = arc._model;
            var options = arc._options;
            var getHoverColor = helpers$1.getHoverColor;
            var valueOrDefault = helpers$1.valueOrDefault;

            arc.$previousStyle = {
                backgroundColor: model.backgroundColor,
                borderColor: model.borderColor,
                borderWidth: model.borderWidth,
            };

            model.backgroundColor = valueOrDefault(options.hoverBackgroundColor, getHoverColor(options.backgroundColor));
            model.borderColor = valueOrDefault(options.hoverBorderColor, getHoverColor(options.borderColor));
            model.borderWidth = valueOrDefault(options.hoverBorderWidth, options.borderWidth);
        },

        /**
         * @private
         */
        _resolveElementOptions: function (arc, index) {
            var me = this;
            var chart = me.chart;
            var dataset = me.getDataset();
            var custom = arc.custom || {};
            var options = chart.options.elements.arc;
            var values = {};
            var i, ilen, key;

            // Scriptable options
            var context = {
                chart: chart,
                dataIndex: index,
                dataset: dataset,
                datasetIndex: me.index
            };

            var keys = [
                'backgroundColor',
                'borderColor',
                'borderWidth',
                'borderAlign',
                'hoverBackgroundColor',
                'hoverBorderColor',
                'hoverBorderWidth',
            ];

            for (i = 0, ilen = keys.length; i < ilen; ++i) {
                key = keys[i];
                values[key] = resolve$5([
                    custom[key],
                    dataset[key],
                    options[key]
                ], context, index);
            }

            return values;
        },

        /**
         * @private
         */
        _computeAngle: function (index) {
            var me = this;
            var count = this.getMeta().count;
            var dataset = me.getDataset();
            var meta = me.getMeta();

            if (isNaN(dataset.data[index]) || meta.data[index].hidden) {
                return 0;
            }

            // Scriptable options
            var context = {
                chart: me.chart,
                dataIndex: index,
                dataset: dataset,
                datasetIndex: me.index
            };

            return resolve$5([
                me.chart.options.elements.arc.angle,
                (2 * Math.PI) / count
            ], context, index);
        }
    });

    core_defaults._set('pie', helpers$1.clone(core_defaults.doughnut));
    core_defaults._set('pie', {
        cutoutPercentage: 0
    });

    // Pie charts are Doughnut chart with different defaults
    var controller_pie = controller_doughnut;

    var valueOrDefault$6 = helpers$1.valueOrDefault;
    var resolve$6 = helpers$1.options.resolve;

    core_defaults._set('radar', {
        scale: {
            type: 'radialLinear'
        },
        elements: {
            line: {
                tension: 0 // no bezier in radar
            }
        }
    });

    var controller_radar = core_datasetController.extend({

        datasetElementType: elements.Line,

        dataElementType: elements.Point,

        linkScales: helpers$1.noop,

        update: function (reset) {
            var me = this;
            var meta = me.getMeta();
            var line = meta.dataset;
            var points = meta.data || [];
            var scale = me.chart.scale;
            var dataset = me.getDataset();
            var i, ilen;

            // Compatibility: If the properties are defined with only the old name, use those values
            if ((dataset.tension !== undefined) && (dataset.lineTension === undefined)) {
                dataset.lineTension = dataset.tension;
            }

            // Utility
            line._scale = scale;
            line._datasetIndex = me.index;
            // Data
            line._children = points;
            line._loop = true;
            // Model
            line._model = me._resolveLineOptions(line);

            line.pivot();

            // Update Points
            for (i = 0, ilen = points.length; i < ilen; ++i) {
                me.updateElement(points[i], i, reset);
            }

            // Update bezier control points
            me.updateBezierControlPoints();

            // Now pivot the point for animation
            for (i = 0, ilen = points.length; i < ilen; ++i) {
                points[i].pivot();
            }
        },

        updateElement: function (point, index, reset) {
            var me = this;
            var custom = point.custom || {};
            var dataset = me.getDataset();
            var scale = me.chart.scale;
            var pointPosition = scale.getPointPositionForValue(index, dataset.data[index]);
            var options = me._resolvePointOptions(point, index);
            var lineModel = me.getMeta().dataset._model;
            var x = reset ? scale.xCenter : pointPosition.x;
            var y = reset ? scale.yCenter : pointPosition.y;

            // Utility
            point._scale = scale;
            point._options = options;
            point._datasetIndex = me.index;
            point._index = index;

            // Desired view properties
            point._model = {
                x: x, // value not used in dataset scale, but we want a consistent API between scales
                y: y,
                skip: custom.skip || isNaN(x) || isNaN(y),
                // Appearance
                radius: options.radius,
                pointStyle: options.pointStyle,
                rotation: options.rotation,
                backgroundColor: options.backgroundColor,
                borderColor: options.borderColor,
                borderWidth: options.borderWidth,
                tension: valueOrDefault$6(custom.tension, lineModel ? lineModel.tension : 0),

                // Tooltip
                hitRadius: options.hitRadius
            };
        },

        /**
         * @private
         */
        _resolvePointOptions: function (element, index) {
            var me = this;
            var chart = me.chart;
            var dataset = chart.data.datasets[me.index];
            var custom = element.custom || {};
            var options = chart.options.elements.point;
            var values = {};
            var i, ilen, key;

            // Scriptable options
            var context = {
                chart: chart,
                dataIndex: index,
                dataset: dataset,
                datasetIndex: me.index
            };

            var ELEMENT_OPTIONS = {
                backgroundColor: 'pointBackgroundColor',
                borderColor: 'pointBorderColor',
                borderWidth: 'pointBorderWidth',
                hitRadius: 'pointHitRadius',
                hoverBackgroundColor: 'pointHoverBackgroundColor',
                hoverBorderColor: 'pointHoverBorderColor',
                hoverBorderWidth: 'pointHoverBorderWidth',
                hoverRadius: 'pointHoverRadius',
                pointStyle: 'pointStyle',
                radius: 'pointRadius',
                rotation: 'pointRotation'
            };
            var keys = Object.keys(ELEMENT_OPTIONS);

            for (i = 0, ilen = keys.length; i < ilen; ++i) {
                key = keys[i];
                values[key] = resolve$6([
                    custom[key],
                    dataset[ELEMENT_OPTIONS[key]],
                    dataset[key],
                    options[key]
                ], context, index);
            }

            return values;
        },

        /**
         * @private
         */
        _resolveLineOptions: function (element) {
            var me = this;
            var chart = me.chart;
            var dataset = chart.data.datasets[me.index];
            var custom = element.custom || {};
            var options = chart.options.elements.line;
            var values = {};
            var i, ilen, key;

            var keys = [
                'backgroundColor',
                'borderWidth',
                'borderColor',
                'borderCapStyle',
                'borderDash',
                'borderDashOffset',
                'borderJoinStyle',
                'fill'
            ];

            for (i = 0, ilen = keys.length; i < ilen; ++i) {
                key = keys[i];
                values[key] = resolve$6([
                    custom[key],
                    dataset[key],
                    options[key]
                ]);
            }

            values.tension = valueOrDefault$6(dataset.lineTension, options.tension);

            return values;
        },

        updateBezierControlPoints: function () {
            var me = this;
            var meta = me.getMeta();
            var area = me.chart.chartArea;
            var points = meta.data || [];
            var i, ilen, model, controlPoints;

            function capControlPoint(pt, min, max) {
                return Math.max(Math.min(pt, max), min);
            }

            for (i = 0, ilen = points.length; i < ilen; ++i) {
                model = points[i]._model;
                controlPoints = helpers$1.splineCurve(
                    helpers$1.previousItem(points, i, true)._model,
                    model,
                    helpers$1.nextItem(points, i, true)._model,
                    model.tension
                );

                // Prevent the bezier going outside of the bounds of the graph
                model.controlPointPreviousX = capControlPoint(controlPoints.previous.x, area.left, area.right);
                model.controlPointPreviousY = capControlPoint(controlPoints.previous.y, area.top, area.bottom);
                model.controlPointNextX = capControlPoint(controlPoints.next.x, area.left, area.right);
                model.controlPointNextY = capControlPoint(controlPoints.next.y, area.top, area.bottom);
            }
        },

        setHoverStyle: function (point) {
            var model = point._model;
            var options = point._options;
            var getHoverColor = helpers$1.getHoverColor;

            point.$previousStyle = {
                backgroundColor: model.backgroundColor,
                borderColor: model.borderColor,
                borderWidth: model.borderWidth,
                radius: model.radius
            };

            model.backgroundColor = valueOrDefault$6(options.hoverBackgroundColor, getHoverColor(options.backgroundColor));
            model.borderColor = valueOrDefault$6(options.hoverBorderColor, getHoverColor(options.borderColor));
            model.borderWidth = valueOrDefault$6(options.hoverBorderWidth, options.borderWidth);
            model.radius = valueOrDefault$6(options.hoverRadius, options.radius);
        }
    });

    core_defaults._set('scatter', {
        hover: {
            mode: 'single'
        },

        scales: {
            xAxes: [{
                id: 'x-axis-1',    // need an ID so datasets can reference the scale
                type: 'linear',    // scatter should not use a category axis
                position: 'bottom'
            }],
            yAxes: [{
                id: 'y-axis-1',
                type: 'linear',
                position: 'left'
            }]
        },

        showLines: false,

        tooltips: {
            callbacks: {
                title: function () {
                    return '';     // doesn't make sense for scatter since data are formatted as a point
                },
                label: function (item) {
                    return '(' + item.xLabel + ', ' + item.yLabel + ')';
                }
            }
        }
    });

    // Scatter charts use line controllers
    var controller_scatter = controller_line;

    // NOTE export a map in which the key represents the controller type, not
    // the class, and so must be CamelCase in order to be correctly retrieved
    // by the controller in core.controller.js (`controllers[meta.type]`).

    var controllers = {
        bar: controller_bar,
        bubble: controller_bubble,
        doughnut: controller_doughnut,
        horizontalBar: controller_horizontalBar,
        line: controller_line,
        polarArea: controller_polarArea,
        pie: controller_pie,
        radar: controller_radar,
        scatter: controller_scatter
    };

    /**
     * Helper function to get relative position for an event
     * @param {Event|IEvent} event - The event to get the position for
     * @param {Chart} chart - The chart
     * @returns {object} the event position
     */
    function getRelativePosition(e, chart) {
        if (e.native) {
            return {
                x: e.x,
                y: e.y
            };
        }

        return helpers$1.getRelativePosition(e, chart);
    }

    /**
     * Helper function to traverse all of the visible elements in the chart
     * @param {Chart} chart - the chart
     * @param {function} handler - the callback to execute for each visible item
     */
    function parseVisibleItems(chart, handler) {
        var datasets = chart.data.datasets;
        var meta, i, j, ilen, jlen;

        for (i = 0, ilen = datasets.length; i < ilen; ++i) {
            if (!chart.isDatasetVisible(i)) {
                continue;
            }

            meta = chart.getDatasetMeta(i);
            for (j = 0, jlen = meta.data.length; j < jlen; ++j) {
                var element = meta.data[j];
                if (!element._view.skip) {
                    handler(element);
                }
            }
        }
    }

    /**
     * Helper function to get the items that intersect the event position
     * @param {ChartElement[]} items - elements to filter
     * @param {object} position - the point to be nearest to
     * @return {ChartElement[]} the nearest items
     */
    function getIntersectItems(chart, position) {
        var elements = [];

        parseVisibleItems(chart, function (element) {
            if (element.inRange(position.x, position.y)) {
                elements.push(element);
            }
        });

        return elements;
    }

    /**
     * Helper function to get the items nearest to the event position considering all visible items in teh chart
     * @param {Chart} chart - the chart to look at elements from
     * @param {object} position - the point to be nearest to
     * @param {boolean} intersect - if true, only consider items that intersect the position
     * @param {function} distanceMetric - function to provide the distance between points
     * @return {ChartElement[]} the nearest items
     */
    function getNearestItems(chart, position, intersect, distanceMetric) {
        var minDistance = Number.POSITIVE_INFINITY;
        var nearestItems = [];

        parseVisibleItems(chart, function (element) {
            if (intersect && !element.inRange(position.x, position.y)) {
                return;
            }

            var center = element.getCenterPoint();
            var distance = distanceMetric(position, center);
            if (distance < minDistance) {
                nearestItems = [element];
                minDistance = distance;
            } else if (distance === minDistance) {
                // Can have multiple items at the same distance in which case we sort by size
                nearestItems.push(element);
            }
        });

        return nearestItems;
    }

    /**
     * Get a distance metric function for two points based on the
     * axis mode setting
     * @param {string} axis - the axis mode. x|y|xy
     */
    function getDistanceMetricForAxis(axis) {
        var useX = axis.indexOf('x') !== -1;
        var useY = axis.indexOf('y') !== -1;

        return function (pt1, pt2) {
            var deltaX = useX ? Math.abs(pt1.x - pt2.x) : 0;
            var deltaY = useY ? Math.abs(pt1.y - pt2.y) : 0;
            return Math.sqrt(Math.pow(deltaX, 2) + Math.pow(deltaY, 2));
        };
    }

    function indexMode(chart, e, options) {
        var position = getRelativePosition(e, chart);
        // Default axis for index mode is 'x' to match old behaviour
        options.axis = options.axis || 'x';
        var distanceMetric = getDistanceMetricForAxis(options.axis);
        var items = options.intersect ? getIntersectItems(chart, position) : getNearestItems(chart, position, false, distanceMetric);
        var elements = [];

        if (!items.length) {
            return [];
        }

        chart.data.datasets.forEach(function (dataset, datasetIndex) {
            if (chart.isDatasetVisible(datasetIndex)) {
                var meta = chart.getDatasetMeta(datasetIndex);
                var element = meta.data[items[0]._index];

                // don't count items that are skipped (null data)
                if (element && !element._view.skip) {
                    elements.push(element);
                }
            }
        });

        return elements;
    }

    /**
     * @interface IInteractionOptions
     */
    /**
     * If true, only consider items that intersect the point
     * @name IInterfaceOptions#boolean
     * @type Boolean
     */

    /**
     * Contains interaction related functions
     * @namespace Chart.Interaction
     */
    var core_interaction = {
        // Helper function for different modes
        modes: {
            single: function (chart, e) {
                var position = getRelativePosition(e, chart);
                var elements = [];

                parseVisibleItems(chart, function (element) {
                    if (element.inRange(position.x, position.y)) {
                        elements.push(element);
                        return elements;
                    }
                });

                return elements.slice(0, 1);
            },

            /**
             * @function Chart.Interaction.modes.label
             * @deprecated since version 2.4.0
             * @todo remove at version 3
             * @private
             */
            label: indexMode,

            /**
             * Returns items at the same index. If the options.intersect parameter is true, we only return items if we intersect something
             * If the options.intersect mode is false, we find the nearest item and return the items at the same index as that item
             * @function Chart.Interaction.modes.index
             * @since v2.4.0
             * @param {Chart} chart - the chart we are returning items from
             * @param {Event} e - the event we are find things at
             * @param {IInteractionOptions} options - options to use during interaction
             * @return {Chart.Element[]} Array of elements that are under the point. If none are found, an empty array is returned
             */
            index: indexMode,

            /**
             * Returns items in the same dataset. If the options.intersect parameter is true, we only return items if we intersect something
             * If the options.intersect is false, we find the nearest item and return the items in that dataset
             * @function Chart.Interaction.modes.dataset
             * @param {Chart} chart - the chart we are returning items from
             * @param {Event} e - the event we are find things at
             * @param {IInteractionOptions} options - options to use during interaction
             * @return {Chart.Element[]} Array of elements that are under the point. If none are found, an empty array is returned
             */
            dataset: function (chart, e, options) {
                var position = getRelativePosition(e, chart);
                options.axis = options.axis || 'xy';
                var distanceMetric = getDistanceMetricForAxis(options.axis);
                var items = options.intersect ? getIntersectItems(chart, position) : getNearestItems(chart, position, false, distanceMetric);

                if (items.length > 0) {
                    items = chart.getDatasetMeta(items[0]._datasetIndex).data;
                }

                return items;
            },

            /**
             * @function Chart.Interaction.modes.x-axis
             * @deprecated since version 2.4.0. Use index mode and intersect == true
             * @todo remove at version 3
             * @private
             */
            'x-axis': function (chart, e) {
                return indexMode(chart, e, { intersect: false });
            },

            /**
             * Point mode returns all elements that hit test based on the event position
             * of the event
             * @function Chart.Interaction.modes.intersect
             * @param {Chart} chart - the chart we are returning items from
             * @param {Event} e - the event we are find things at
             * @return {Chart.Element[]} Array of elements that are under the point. If none are found, an empty array is returned
             */
            point: function (chart, e) {
                var position = getRelativePosition(e, chart);
                return getIntersectItems(chart, position);
            },

            /**
             * nearest mode returns the element closest to the point
             * @function Chart.Interaction.modes.intersect
             * @param {Chart} chart - the chart we are returning items from
             * @param {Event} e - the event we are find things at
             * @param {IInteractionOptions} options - options to use
             * @return {Chart.Element[]} Array of elements that are under the point. If none are found, an empty array is returned
             */
            nearest: function (chart, e, options) {
                var position = getRelativePosition(e, chart);
                options.axis = options.axis || 'xy';
                var distanceMetric = getDistanceMetricForAxis(options.axis);
                return getNearestItems(chart, position, options.intersect, distanceMetric);
            },

            /**
             * x mode returns the elements that hit-test at the current x coordinate
             * @function Chart.Interaction.modes.x
             * @param {Chart} chart - the chart we are returning items from
             * @param {Event} e - the event we are find things at
             * @param {IInteractionOptions} options - options to use
             * @return {Chart.Element[]} Array of elements that are under the point. If none are found, an empty array is returned
             */
            x: function (chart, e, options) {
                var position = getRelativePosition(e, chart);
                var items = [];
                var intersectsItem = false;

                parseVisibleItems(chart, function (element) {
                    if (element.inXRange(position.x)) {
                        items.push(element);
                    }

                    if (element.inRange(position.x, position.y)) {
                        intersectsItem = true;
                    }
                });

                // If we want to trigger on an intersect and we don't have any items
                // that intersect the position, return nothing
                if (options.intersect && !intersectsItem) {
                    items = [];
                }
                return items;
            },

            /**
             * y mode returns the elements that hit-test at the current y coordinate
             * @function Chart.Interaction.modes.y
             * @param {Chart} chart - the chart we are returning items from
             * @param {Event} e - the event we are find things at
             * @param {IInteractionOptions} options - options to use
             * @return {Chart.Element[]} Array of elements that are under the point. If none are found, an empty array is returned
             */
            y: function (chart, e, options) {
                var position = getRelativePosition(e, chart);
                var items = [];
                var intersectsItem = false;

                parseVisibleItems(chart, function (element) {
                    if (element.inYRange(position.y)) {
                        items.push(element);
                    }

                    if (element.inRange(position.x, position.y)) {
                        intersectsItem = true;
                    }
                });

                // If we want to trigger on an intersect and we don't have any items
                // that intersect the position, return nothing
                if (options.intersect && !intersectsItem) {
                    items = [];
                }
                return items;
            }
        }
    };

    function filterByPosition(array, position) {
        return helpers$1.where(array, function (v) {
            return v.position === position;
        });
    }

    function sortByWeight(array, reverse) {
        array.forEach(function (v, i) {
            v._tmpIndex_ = i;
            return v;
        });
        array.sort(function (a, b) {
            var v0 = reverse ? b : a;
            var v1 = reverse ? a : b;
            return v0.weight === v1.weight ?
                v0._tmpIndex_ - v1._tmpIndex_ :
                v0.weight - v1.weight;
        });
        array.forEach(function (v) {
            delete v._tmpIndex_;
        });
    }

    function findMaxPadding(boxes) {
        var top = 0;
        var left = 0;
        var bottom = 0;
        var right = 0;
        helpers$1.each(boxes, function (box) {
            if (box.getPadding) {
                var boxPadding = box.getPadding();
                top = Math.max(top, boxPadding.top);
                left = Math.max(left, boxPadding.left);
                bottom = Math.max(bottom, boxPadding.bottom);
                right = Math.max(right, boxPadding.right);
            }
        });
        return {
            top: top,
            left: left,
            bottom: bottom,
            right: right
        };
    }

    function addSizeByPosition(boxes, size) {
        helpers$1.each(boxes, function (box) {
            size[box.position] += box.isHorizontal() ? box.height : box.width;
        });
    }

    core_defaults._set('global', {
        layout: {
            padding: {
                top: 0,
                right: 0,
                bottom: 0,
                left: 0
            }
        }
    });

    /**
     * @interface ILayoutItem
     * @prop {string} position - The position of the item in the chart layout. Possible values are
     * 'left', 'top', 'right', 'bottom', and 'chartArea'
     * @prop {number} weight - The weight used to sort the item. Higher weights are further away from the chart area
     * @prop {boolean} fullWidth - if true, and the item is horizontal, then push vertical boxes down
     * @prop {function} isHorizontal - returns true if the layout item is horizontal (ie. top or bottom)
     * @prop {function} update - Takes two parameters: width and height. Returns size of item
     * @prop {function} getPadding -  Returns an object with padding on the edges
     * @prop {number} width - Width of item. Must be valid after update()
     * @prop {number} height - Height of item. Must be valid after update()
     * @prop {number} left - Left edge of the item. Set by layout system and cannot be used in update
     * @prop {number} top - Top edge of the item. Set by layout system and cannot be used in update
     * @prop {number} right - Right edge of the item. Set by layout system and cannot be used in update
     * @prop {number} bottom - Bottom edge of the item. Set by layout system and cannot be used in update
     */

    // The layout service is very self explanatory.  It's responsible for the layout within a chart.
    // Scales, Legends and Plugins all rely on the layout service and can easily register to be placed anywhere they need
    // It is this service's responsibility of carrying out that layout.
    var core_layouts = {
        defaults: {},

        /**
         * Register a box to a chart.
         * A box is simply a reference to an object that requires layout. eg. Scales, Legend, Title.
         * @param {Chart} chart - the chart to use
         * @param {ILayoutItem} item - the item to add to be layed out
         */
        addBox: function (chart, item) {
            if (!chart.boxes) {
                chart.boxes = [];
            }

            // initialize item with default values
            item.fullWidth = item.fullWidth || false;
            item.position = item.position || 'top';
            item.weight = item.weight || 0;

            chart.boxes.push(item);
        },

        /**
         * Remove a layoutItem from a chart
         * @param {Chart} chart - the chart to remove the box from
         * @param {ILayoutItem} layoutItem - the item to remove from the layout
         */
        removeBox: function (chart, layoutItem) {
            var index = chart.boxes ? chart.boxes.indexOf(layoutItem) : -1;
            if (index !== -1) {
                chart.boxes.splice(index, 1);
            }
        },

        /**
         * Sets (or updates) options on the given `item`.
         * @param {Chart} chart - the chart in which the item lives (or will be added to)
         * @param {ILayoutItem} item - the item to configure with the given options
         * @param {object} options - the new item options.
         */
        configure: function (chart, item, options) {
            var props = ['fullWidth', 'position', 'weight'];
            var ilen = props.length;
            var i = 0;
            var prop;

            for (; i < ilen; ++i) {
                prop = props[i];
                if (options.hasOwnProperty(prop)) {
                    item[prop] = options[prop];
                }
            }
        },

        /**
         * Fits boxes of the given chart into the given size by having each box measure itself
         * then running a fitting algorithm
         * @param {Chart} chart - the chart
         * @param {number} width - the width to fit into
         * @param {number} height - the height to fit into
         */
        update: function (chart, width, height) {
            if (!chart) {
                return;
            }

            var layoutOptions = chart.options.layout || {};
            var padding = helpers$1.options.toPadding(layoutOptions.padding);
            var leftPadding = padding.left;
            var rightPadding = padding.right;
            var topPadding = padding.top;
            var bottomPadding = padding.bottom;

            var leftBoxes = filterByPosition(chart.boxes, 'left');
            var rightBoxes = filterByPosition(chart.boxes, 'right');
            var topBoxes = filterByPosition(chart.boxes, 'top');
            var bottomBoxes = filterByPosition(chart.boxes, 'bottom');
            var chartAreaBoxes = filterByPosition(chart.boxes, 'chartArea');

            // Sort boxes by weight. A higher weight is further away from the chart area
            sortByWeight(leftBoxes, true);
            sortByWeight(rightBoxes, false);
            sortByWeight(topBoxes, true);
            sortByWeight(bottomBoxes, false);

            var verticalBoxes = leftBoxes.concat(rightBoxes);
            var horizontalBoxes = topBoxes.concat(bottomBoxes);
            var outerBoxes = verticalBoxes.concat(horizontalBoxes);

            // Essentially we now have any number of boxes on each of the 4 sides.
            // Our canvas looks like the following.
            // The areas L1 and L2 are the left axes. R1 is the right axis, T1 is the top axis and
            // B1 is the bottom axis
            // There are also 4 quadrant-like locations (left to right instead of clockwise) reserved for chart overlays
            // These locations are single-box locations only, when trying to register a chartArea location that is already taken,
            // an error will be thrown.
            //
            // |----------------------------------------------------|
            // |                  T1 (Full Width)                   |
            // |----------------------------------------------------|
            // |    |    |                 T2                  |    |
            // |    |----|-------------------------------------|----|
            // |    |    | C1 |                           | C2 |    |
            // |    |    |----|                           |----|    |
            // |    |    |                                     |    |
            // | L1 | L2 |           ChartArea (C0)            | R1 |
            // |    |    |                                     |    |
            // |    |    |----|                           |----|    |
            // |    |    | C3 |                           | C4 |    |
            // |    |----|-------------------------------------|----|
            // |    |    |                 B1                  |    |
            // |----------------------------------------------------|
            // |                  B2 (Full Width)                   |
            // |----------------------------------------------------|
            //
            // What we do to find the best sizing, we do the following
            // 1. Determine the minimum size of the chart area.
            // 2. Split the remaining width equally between each vertical axis
            // 3. Split the remaining height equally between each horizontal axis
            // 4. Give each layout the maximum size it can be. The layout will return it's minimum size
            // 5. Adjust the sizes of each axis based on it's minimum reported size.
            // 6. Refit each axis
            // 7. Position each axis in the final location
            // 8. Tell the chart the final location of the chart area
            // 9. Tell any axes that overlay the chart area the positions of the chart area

            // Step 1
            var chartWidth = width - leftPadding - rightPadding;
            var chartHeight = height - topPadding - bottomPadding;
            var chartAreaWidth = chartWidth / 2; // min 50%

            // Step 2
            var verticalBoxWidth = (width - chartAreaWidth) / verticalBoxes.length;

            // Step 3
            // TODO re-limit horizontal axis height (this limit has affected only padding calculation since PR 1837)
            // var horizontalBoxHeight = (height - chartAreaHeight) / horizontalBoxes.length;

            // Step 4
            var maxChartAreaWidth = chartWidth;
            var maxChartAreaHeight = chartHeight;
            var outerBoxSizes = { top: topPadding, left: leftPadding, bottom: bottomPadding, right: rightPadding };
            var minBoxSizes = [];
            var maxPadding;

            function getMinimumBoxSize(box) {
                var minSize;
                var isHorizontal = box.isHorizontal();

                if (isHorizontal) {
                    minSize = box.update(box.fullWidth ? chartWidth : maxChartAreaWidth, chartHeight / 2);
                    maxChartAreaHeight -= minSize.height;
                } else {
                    minSize = box.update(verticalBoxWidth, maxChartAreaHeight);
                    maxChartAreaWidth -= minSize.width;
                }

                minBoxSizes.push({
                    horizontal: isHorizontal,
                    width: minSize.width,
                    box: box,
                });
            }

            helpers$1.each(outerBoxes, getMinimumBoxSize);

            // If a horizontal box has padding, we move the left boxes over to avoid ugly charts (see issue #2478)
            maxPadding = findMaxPadding(outerBoxes);

            // At this point, maxChartAreaHeight and maxChartAreaWidth are the size the chart area could
            // be if the axes are drawn at their minimum sizes.
            // Steps 5 & 6

            // Function to fit a box
            function fitBox(box) {
                var minBoxSize = helpers$1.findNextWhere(minBoxSizes, function (minBox) {
                    return minBox.box === box;
                });

                if (minBoxSize) {
                    if (minBoxSize.horizontal) {
                        var scaleMargin = {
                            left: Math.max(outerBoxSizes.left, maxPadding.left),
                            right: Math.max(outerBoxSizes.right, maxPadding.right),
                            top: 0,
                            bottom: 0
                        };

                        // Don't use min size here because of label rotation. When the labels are rotated, their rotation highly depends
                        // on the margin. Sometimes they need to increase in size slightly
                        box.update(box.fullWidth ? chartWidth : maxChartAreaWidth, chartHeight / 2, scaleMargin);
                    } else {
                        box.update(minBoxSize.width, maxChartAreaHeight);
                    }
                }
            }

            // Update, and calculate the left and right margins for the horizontal boxes
            helpers$1.each(verticalBoxes, fitBox);
            addSizeByPosition(verticalBoxes, outerBoxSizes);

            // Set the Left and Right margins for the horizontal boxes
            helpers$1.each(horizontalBoxes, fitBox);
            addSizeByPosition(horizontalBoxes, outerBoxSizes);

            function finalFitVerticalBox(box) {
                var minBoxSize = helpers$1.findNextWhere(minBoxSizes, function (minSize) {
                    return minSize.box === box;
                });

                var scaleMargin = {
                    left: 0,
                    right: 0,
                    top: outerBoxSizes.top,
                    bottom: outerBoxSizes.bottom
                };

                if (minBoxSize) {
                    box.update(minBoxSize.width, maxChartAreaHeight, scaleMargin);
                }
            }

            // Let the left layout know the final margin
            helpers$1.each(verticalBoxes, finalFitVerticalBox);

            // Recalculate because the size of each layout might have changed slightly due to the margins (label rotation for instance)
            outerBoxSizes = { top: topPadding, left: leftPadding, bottom: bottomPadding, right: rightPadding };
            addSizeByPosition(outerBoxes, outerBoxSizes);

            // We may be adding some padding to account for rotated x axis labels
            var leftPaddingAddition = Math.max(maxPadding.left - outerBoxSizes.left, 0);
            outerBoxSizes.left += leftPaddingAddition;
            outerBoxSizes.right += Math.max(maxPadding.right - outerBoxSizes.right, 0);

            var topPaddingAddition = Math.max(maxPadding.top - outerBoxSizes.top, 0);
            outerBoxSizes.top += topPaddingAddition;
            outerBoxSizes.bottom += Math.max(maxPadding.bottom - outerBoxSizes.bottom, 0);

            // Figure out if our chart area changed. This would occur if the dataset layout label rotation
            // changed due to the application of the margins in step 6. Since we can only get bigger, this is safe to do
            // without calling `fit` again
            var newMaxChartAreaHeight = height - outerBoxSizes.top - outerBoxSizes.bottom;
            var newMaxChartAreaWidth = width - outerBoxSizes.left - outerBoxSizes.right;

            if (newMaxChartAreaWidth !== maxChartAreaWidth || newMaxChartAreaHeight !== maxChartAreaHeight) {
                helpers$1.each(verticalBoxes, function (box) {
                    box.height = newMaxChartAreaHeight;
                });

                helpers$1.each(horizontalBoxes, function (box) {
                    if (!box.fullWidth) {
                        box.width = newMaxChartAreaWidth;
                    }
                });

                maxChartAreaHeight = newMaxChartAreaHeight;
                maxChartAreaWidth = newMaxChartAreaWidth;
            }

            // Step 7 - Position the boxes
            var left = leftPadding + leftPaddingAddition;
            var top = topPadding + topPaddingAddition;

            function placeBox(box) {
                if (box.isHorizontal()) {
                    box.left = box.fullWidth ? leftPadding : outerBoxSizes.left;
                    box.right = box.fullWidth ? width - rightPadding : outerBoxSizes.left + maxChartAreaWidth;
                    box.top = top;
                    box.bottom = top + box.height;

                    // Move to next point
                    top = box.bottom;

                } else {

                    box.left = left;
                    box.right = left + box.width;
                    box.top = outerBoxSizes.top;
                    box.bottom = outerBoxSizes.top + maxChartAreaHeight;

                    // Move to next point
                    left = box.right;
                }
            }

            helpers$1.each(leftBoxes.concat(topBoxes), placeBox);

            // Account for chart width and height
            left += maxChartAreaWidth;
            top += maxChartAreaHeight;

            helpers$1.each(rightBoxes, placeBox);
            helpers$1.each(bottomBoxes, placeBox);

            // Step 8
            chart.chartArea = {
                left: outerBoxSizes.left,
                top: outerBoxSizes.top,
                right: outerBoxSizes.left + maxChartAreaWidth,
                bottom: outerBoxSizes.top + maxChartAreaHeight
            };

            // Step 9
            helpers$1.each(chartAreaBoxes, function (box) {
                box.left = chart.chartArea.left;
                box.top = chart.chartArea.top;
                box.right = chart.chartArea.right;
                box.bottom = chart.chartArea.bottom;

                box.update(maxChartAreaWidth, maxChartAreaHeight);
            });
        }
    };

    /**
     * Platform fallback implementation (minimal).
     * @see https://github.com/chartjs/Chart.js/pull/4591#issuecomment-319575939
     */

    var platform_basic = {
        acquireContext: function (item) {
            if (item && item.canvas) {
                // Support for any object associated to a canvas (including a context2d)
                item = item.canvas;
            }

            return item && item.getContext('2d') || null;
        }
    };

    var platform_dom = "/*\n * DOM element rendering detection\n * https://davidwalsh.name/detect-node-insertion\n */\n@keyframes chartjs-render-animation {\n\tfrom { opacity: 0.99; }\n\tto { opacity: 1; }\n}\n\n.chartjs-render-monitor {\n\tanimation: chartjs-render-animation 0.001s;\n}\n\n/*\n * DOM element resizing detection\n * https://github.com/marcj/css-element-queries\n */\n.chartjs-size-monitor,\n.chartjs-size-monitor-expand,\n.chartjs-size-monitor-shrink {\n\tposition: absolute;\n\tdirection: ltr;\n\tleft: 0;\n\ttop: 0;\n\tright: 0;\n\tbottom: 0;\n\toverflow: hidden;\n\tpointer-events: none;\n\tvisibility: hidden;\n\tz-index: -1;\n}\n\n.chartjs-size-monitor-expand > div {\n\tposition: absolute;\n\twidth: 1000000px;\n\theight: 1000000px;\n\tleft: 0;\n\ttop: 0;\n}\n\n.chartjs-size-monitor-shrink > div {\n\tposition: absolute;\n\twidth: 200%;\n\theight: 200%;\n\tleft: 0;\n\ttop: 0;\n}\n";

    var platform_dom$1 = /*#__PURE__*/Object.freeze({
        default: platform_dom
    });

    function getCjsExportFromNamespace(n) {
        return n && n.default || n;
    }

    var stylesheet = getCjsExportFromNamespace(platform_dom$1);

    var EXPANDO_KEY = '$chartjs';
    var CSS_PREFIX = 'chartjs-';
    var CSS_SIZE_MONITOR = CSS_PREFIX + 'size-monitor';
    var CSS_RENDER_MONITOR = CSS_PREFIX + 'render-monitor';
    var CSS_RENDER_ANIMATION = CSS_PREFIX + 'render-animation';
    var ANIMATION_START_EVENTS = ['animationstart', 'webkitAnimationStart'];

    /**
     * DOM event types -> Chart.js event types.
     * Note: only events with different types are mapped.
     * @see https://developer.mozilla.org/en-US/docs/Web/Events
     */
    var EVENT_TYPES = {
        touchstart: 'mousedown',
        touchmove: 'mousemove',
        touchend: 'mouseup',
        pointerenter: 'mouseenter',
        pointerdown: 'mousedown',
        pointermove: 'mousemove',
        pointerup: 'mouseup',
        pointerleave: 'mouseout',
        pointerout: 'mouseout'
    };

    /**
     * The "used" size is the final value of a dimension property after all calculations have
     * been performed. This method uses the computed style of `element` but returns undefined
     * if the computed style is not expressed in pixels. That can happen in some cases where
     * `element` has a size relative to its parent and this last one is not yet displayed,
     * for example because of `display: none` on a parent node.
     * @see https://developer.mozilla.org/en-US/docs/Web/CSS/used_value
     * @returns {number} Size in pixels or undefined if unknown.
     */
    function readUsedSize(element, property) {
        var value = helpers$1.getStyle(element, property);
        var matches = value && value.match(/^(\d+)(\.\d+)?px$/);
        return matches ? Number(matches[1]) : undefined;
    }

    /**
     * Initializes the canvas style and render size without modifying the canvas display size,
     * since responsiveness is handled by the controller.resize() method. The config is used
     * to determine the aspect ratio to apply in case no explicit height has been specified.
     */
    function initCanvas(canvas, config) {
        var style = canvas.style;

        // NOTE(SB) canvas.getAttribute('width') !== canvas.width: in the first case it
        // returns null or '' if no explicit value has been set to the canvas attribute.
        var renderHeight = canvas.getAttribute('height');
        var renderWidth = canvas.getAttribute('width');

        // Chart.js modifies some canvas values that we want to restore on destroy
        canvas[EXPANDO_KEY] = {
            initial: {
                height: renderHeight,
                width: renderWidth,
                style: {
                    display: style.display,
                    height: style.height,
                    width: style.width
                }
            }
        };

        // Force canvas to display as block to avoid extra space caused by inline
        // elements, which would interfere with the responsive resize process.
        // https://github.com/chartjs/Chart.js/issues/2538
        style.display = style.display || 'block';

        if (renderWidth === null || renderWidth === '') {
            var displayWidth = readUsedSize(canvas, 'width');
            if (displayWidth !== undefined) {
                canvas.width = displayWidth;
            }
        }

        if (renderHeight === null || renderHeight === '') {
            if (canvas.style.height === '') {
                // If no explicit render height and style height, let's apply the aspect ratio,
                // which one can be specified by the user but also by charts as default option
                // (i.e. options.aspectRatio). If not specified, use canvas aspect ratio of 2.
                canvas.height = canvas.width / (config.options.aspectRatio || 2);
            } else {
                var displayHeight = readUsedSize(canvas, 'height');
                if (displayWidth !== undefined) {
                    canvas.height = displayHeight;
                }
            }
        }

        return canvas;
    }

    /**
     * Detects support for options object argument in addEventListener.
     * https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/addEventListener#Safely_detecting_option_support
     * @private
     */
    var supportsEventListenerOptions = (function () {
        var supports = false;
        try {
            var options = Object.defineProperty({}, 'passive', {
                // eslint-disable-next-line getter-return
                get: function () {
                    supports = true;
                }
            });
            window.addEventListener('e', null, options);
        } catch (e) {
            // continue regardless of error
        }
        return supports;
    }());

    // Default passive to true as expected by Chrome for 'touchstart' and 'touchend' events.
    // https://github.com/chartjs/Chart.js/issues/4287
    var eventListenerOptions = supportsEventListenerOptions ? { passive: true } : false;

    function addListener(node, type, listener) {
        node.addEventListener(type, listener, eventListenerOptions);
    }

    function removeListener(node, type, listener) {
        node.removeEventListener(type, listener, eventListenerOptions);
    }

    function createEvent(type, chart, x, y, nativeEvent) {
        return {
            type: type,
            chart: chart,
            native: nativeEvent || null,
            x: x !== undefined ? x : null,
            y: y !== undefined ? y : null,
        };
    }

    function fromNativeEvent(event, chart) {
        var type = EVENT_TYPES[event.type] || event.type;
        var pos = helpers$1.getRelativePosition(event, chart);
        return createEvent(type, chart, pos.x, pos.y, event);
    }

    function throttled(fn, thisArg) {
        var ticking = false;
        var args = [];

        return function () {
            args = Array.prototype.slice.call(arguments);
            thisArg = thisArg || this;

            if (!ticking) {
                ticking = true;
                helpers$1.requestAnimFrame.call(window, function () {
                    ticking = false;
                    fn.apply(thisArg, args);
                });
            }
        };
    }

    function createDiv(cls) {
        var el = document.createElement('div');
        el.className = cls || '';
        return el;
    }

    // Implementation based on https://github.com/marcj/css-element-queries
    function createResizer(handler) {
        var maxSize = 1000000;

        // NOTE(SB) Don't use innerHTML because it could be considered unsafe.
        // https://github.com/chartjs/Chart.js/issues/5902
        var resizer = createDiv(CSS_SIZE_MONITOR);
        var expand = createDiv(CSS_SIZE_MONITOR + '-expand');
        var shrink = createDiv(CSS_SIZE_MONITOR + '-shrink');

        expand.appendChild(createDiv());
        shrink.appendChild(createDiv());

        resizer.appendChild(expand);
        resizer.appendChild(shrink);
        resizer._reset = function () {
            expand.scrollLeft = maxSize;
            expand.scrollTop = maxSize;
            shrink.scrollLeft = maxSize;
            shrink.scrollTop = maxSize;
        };

        var onScroll = function () {
            resizer._reset();
            handler();
        };

        addListener(expand, 'scroll', onScroll.bind(expand, 'expand'));
        addListener(shrink, 'scroll', onScroll.bind(shrink, 'shrink'));

        return resizer;
    }

    // https://davidwalsh.name/detect-node-insertion
    function watchForRender(node, handler) {
        var expando = node[EXPANDO_KEY] || (node[EXPANDO_KEY] = {});
        var proxy = expando.renderProxy = function (e) {
            if (e.animationName === CSS_RENDER_ANIMATION) {
                handler();
            }
        };

        helpers$1.each(ANIMATION_START_EVENTS, function (type) {
            addListener(node, type, proxy);
        });

        // #4737: Chrome might skip the CSS animation when the CSS_RENDER_MONITOR class
        // is removed then added back immediately (same animation frame?). Accessing the
        // `offsetParent` property will force a reflow and re-evaluate the CSS animation.
        // https://gist.github.com/paulirish/5d52fb081b3570c81e3a#box-metrics
        // https://github.com/chartjs/Chart.js/issues/4737
        expando.reflow = !!node.offsetParent;

        node.classList.add(CSS_RENDER_MONITOR);
    }

    function unwatchForRender(node) {
        var expando = node[EXPANDO_KEY] || {};
        var proxy = expando.renderProxy;

        if (proxy) {
            helpers$1.each(ANIMATION_START_EVENTS, function (type) {
                removeListener(node, type, proxy);
            });

            delete expando.renderProxy;
        }

        node.classList.remove(CSS_RENDER_MONITOR);
    }

    function addResizeListener(node, listener, chart) {
        var expando = node[EXPANDO_KEY] || (node[EXPANDO_KEY] = {});

        // Let's keep track of this added resizer and thus avoid DOM query when removing it.
        var resizer = expando.resizer = createResizer(throttled(function () {
            if (expando.resizer) {
                var container = chart.options.maintainAspectRatio && node.parentNode;
                var w = container ? container.clientWidth : 0;
                listener(createEvent('resize', chart));
                if (container && container.clientWidth < w && chart.canvas) {
                    // If the container size shrank during chart resize, let's assume
                    // scrollbar appeared. So we resize again with the scrollbar visible -
                    // effectively making chart smaller and the scrollbar hidden again.
                    // Because we are inside `throttled`, and currently `ticking`, scroll
                    // events are ignored during this whole 2 resize process.
                    // If we assumed wrong and something else happened, we are resizing
                    // twice in a frame (potential performance issue)
                    listener(createEvent('resize', chart));
                }
            }
        }));

        // The resizer needs to be attached to the node parent, so we first need to be
        // sure that `node` is attached to the DOM before injecting the resizer element.
        watchForRender(node, function () {
            if (expando.resizer) {
                var container = node.parentNode;
                if (container && container !== resizer.parentNode) {
                    container.insertBefore(resizer, container.firstChild);
                }

                // The container size might have changed, let's reset the resizer state.
                resizer._reset();
            }
        });
    }

    function removeResizeListener(node) {
        var expando = node[EXPANDO_KEY] || {};
        var resizer = expando.resizer;

        delete expando.resizer;
        unwatchForRender(node);

        if (resizer && resizer.parentNode) {
            resizer.parentNode.removeChild(resizer);
        }
    }

    function injectCSS(platform, css) {
        // https://stackoverflow.com/q/3922139
        var style = platform._style || document.createElement('style');
        if (!platform._style) {
            platform._style = style;
            css = '/* Chart.js */\n' + css;
            style.setAttribute('type', 'text/css');
            document.getElementsByTagName('head')[0].appendChild(style);
        }

        style.appendChild(document.createTextNode(css));
    }

    var platform_dom$2 = {
        /**
         * When `true`, prevents the automatic injection of the stylesheet required to
         * correctly detect when the chart is added to the DOM and then resized. This
         * switch has been added to allow external stylesheet (`dist/Chart(.min)?.js`)
         * to be manually imported to make this library compatible with any CSP.
         * See https://github.com/chartjs/Chart.js/issues/5208
         */
        disableCSSInjection: false,

        /**
         * This property holds whether this platform is enabled for the current environment.
         * Currently used by platform.js to select the proper implementation.
         * @private
         */
        _enabled: typeof window !== 'undefined' && typeof document !== 'undefined',

        /**
         * @private
         */
        _ensureLoaded: function () {
            if (this._loaded) {
                return;
            }

            this._loaded = true;

            // https://github.com/chartjs/Chart.js/issues/5208
            if (!this.disableCSSInjection) {
                injectCSS(this, stylesheet);
            }
        },

        acquireContext: function (item, config) {
            if (typeof item === 'string') {
                item = document.getElementById(item);
            } else if (item.length) {
                // Support for array based queries (such as jQuery)
                item = item[0];
            }

            if (item && item.canvas) {
                // Support for any object associated to a canvas (including a context2d)
                item = item.canvas;
            }

            // To prevent canvas fingerprinting, some add-ons undefine the getContext
            // method, for example: https://github.com/kkapsner/CanvasBlocker
            // https://github.com/chartjs/Chart.js/issues/2807
            var context = item && item.getContext && item.getContext('2d');

            // Load platform resources on first chart creation, to make possible to change
            // platform options after importing the library (e.g. `disableCSSInjection`).
            this._ensureLoaded();

            // `instanceof HTMLCanvasElement/CanvasRenderingContext2D` fails when the item is
            // inside an iframe or when running in a protected environment. We could guess the
            // types from their toString() value but let's keep things flexible and assume it's
            // a sufficient condition if the item has a context2D which has item as `canvas`.
            // https://github.com/chartjs/Chart.js/issues/3887
            // https://github.com/chartjs/Chart.js/issues/4102
            // https://github.com/chartjs/Chart.js/issues/4152
            if (context && context.canvas === item) {
                initCanvas(item, config);
                return context;
            }

            return null;
        },

        releaseContext: function (context) {
            var canvas = context.canvas;
            if (!canvas[EXPANDO_KEY]) {
                return;
            }

            var initial = canvas[EXPANDO_KEY].initial;
            ['height', 'width'].forEach(function (prop) {
                var value = initial[prop];
                if (helpers$1.isNullOrUndef(value)) {
                    canvas.removeAttribute(prop);
                } else {
                    canvas.setAttribute(prop, value);
                }
            });

            helpers$1.each(initial.style || {}, function (value, key) {
                canvas.style[key] = value;
            });

            // The canvas render size might have been changed (and thus the state stack discarded),
            // we can't use save() and restore() to restore the initial state. So make sure that at
            // least the canvas context is reset to the default state by setting the canvas width.
            // https://www.w3.org/TR/2011/WD-html5-20110525/the-canvas-element.html
            // eslint-disable-next-line no-self-assign
            canvas.width = canvas.width;

            delete canvas[EXPANDO_KEY];
        },

        addEventListener: function (chart, type, listener) {
            var canvas = chart.canvas;
            if (type === 'resize') {
                // Note: the resize event is not supported on all browsers.
                addResizeListener(canvas, listener, chart);
                return;
            }

            var expando = listener[EXPANDO_KEY] || (listener[EXPANDO_KEY] = {});
            var proxies = expando.proxies || (expando.proxies = {});
            var proxy = proxies[chart.id + '_' + type] = function (event) {
                listener(fromNativeEvent(event, chart));
            };

            addListener(canvas, type, proxy);
        },

        removeEventListener: function (chart, type, listener) {
            var canvas = chart.canvas;
            if (type === 'resize') {
                // Note: the resize event is not supported on all browsers.
                removeResizeListener(canvas);
                return;
            }

            var expando = listener[EXPANDO_KEY] || {};
            var proxies = expando.proxies || {};
            var proxy = proxies[chart.id + '_' + type];
            if (!proxy) {
                return;
            }

            removeListener(canvas, type, proxy);
        }
    };

    // DEPRECATIONS

    /**
     * Provided for backward compatibility, use EventTarget.addEventListener instead.
     * EventTarget.addEventListener compatibility: Chrome, Opera 7, Safari, FF1.5+, IE9+
     * @see https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/addEventListener
     * @function Chart.helpers.addEvent
     * @deprecated since version 2.7.0
     * @todo remove at version 3
     * @private
     */
    helpers$1.addEvent = addListener;

    /**
     * Provided for backward compatibility, use EventTarget.removeEventListener instead.
     * EventTarget.removeEventListener compatibility: Chrome, Opera 7, Safari, FF1.5+, IE9+
     * @see https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/removeEventListener
     * @function Chart.helpers.removeEvent
     * @deprecated since version 2.7.0
     * @todo remove at version 3
     * @private
     */
    helpers$1.removeEvent = removeListener;

    // @TODO Make possible to select another platform at build time.
    var implementation = platform_dom$2._enabled ? platform_dom$2 : platform_basic;

    /**
     * @namespace Chart.platform
     * @see https://chartjs.gitbooks.io/proposals/content/Platform.html
     * @since 2.4.0
     */
    var platform = helpers$1.extend({
        /**
         * @since 2.7.0
         */
        initialize: function () { },

        /**
         * Called at chart construction time, returns a context2d instance implementing
         * the [W3C Canvas 2D Context API standard]{@link https://www.w3.org/TR/2dcontext/}.
         * @param {*} item - The native item from which to acquire context (platform specific)
         * @param {object} options - The chart options
         * @returns {CanvasRenderingContext2D} context2d instance
         */
        acquireContext: function () { },

        /**
         * Called at chart destruction time, releases any resources associated to the context
         * previously returned by the acquireContext() method.
         * @param {CanvasRenderingContext2D} context - The context2d instance
         * @returns {boolean} true if the method succeeded, else false
         */
        releaseContext: function () { },

        /**
         * Registers the specified listener on the given chart.
         * @param {Chart} chart - Chart from which to listen for event
         * @param {string} type - The ({@link IEvent}) type to listen for
         * @param {function} listener - Receives a notification (an object that implements
         * the {@link IEvent} interface) when an event of the specified type occurs.
         */
        addEventListener: function () { },

        /**
         * Removes the specified listener previously registered with addEventListener.
         * @param {Chart} chart - Chart from which to remove the listener
         * @param {string} type - The ({@link IEvent}) type to remove
         * @param {function} listener - The listener function to remove from the event target.
         */
        removeEventListener: function () { }

    }, implementation);

    core_defaults._set('global', {
        plugins: {}
    });

    /**
     * The plugin service singleton
     * @namespace Chart.plugins
     * @since 2.1.0
     */
    var core_plugins = {
        /**
         * Globally registered plugins.
         * @private
         */
        _plugins: [],

        /**
         * This identifier is used to invalidate the descriptors cache attached to each chart
         * when a global plugin is registered or unregistered. In this case, the cache ID is
         * incremented and descriptors are regenerated during following API calls.
         * @private
         */
        _cacheId: 0,

        /**
         * Registers the given plugin(s) if not already registered.
         * @param {IPlugin[]|IPlugin} plugins plugin instance(s).
         */
        register: function (plugins) {
            var p = this._plugins;
            ([]).concat(plugins).forEach(function (plugin) {
                if (p.indexOf(plugin) === -1) {
                    p.push(plugin);
                }
            });

            this._cacheId++;
        },

        /**
         * Unregisters the given plugin(s) only if registered.
         * @param {IPlugin[]|IPlugin} plugins plugin instance(s).
         */
        unregister: function (plugins) {
            var p = this._plugins;
            ([]).concat(plugins).forEach(function (plugin) {
                var idx = p.indexOf(plugin);
                if (idx !== -1) {
                    p.splice(idx, 1);
                }
            });

            this._cacheId++;
        },

        /**
         * Remove all registered plugins.
         * @since 2.1.5
         */
        clear: function () {
            this._plugins = [];
            this._cacheId++;
        },

        /**
         * Returns the number of registered plugins?
         * @returns {number}
         * @since 2.1.5
         */
        count: function () {
            return this._plugins.length;
        },

        /**
         * Returns all registered plugin instances.
         * @returns {IPlugin[]} array of plugin objects.
         * @since 2.1.5
         */
        getAll: function () {
            return this._plugins;
        },

        /**
         * Calls enabled plugins for `chart` on the specified hook and with the given args.
         * This method immediately returns as soon as a plugin explicitly returns false. The
         * returned value can be used, for instance, to interrupt the current action.
         * @param {Chart} chart - The chart instance for which plugins should be called.
         * @param {string} hook - The name of the plugin method to call (e.g. 'beforeUpdate').
         * @param {Array} [args] - Extra arguments to apply to the hook call.
         * @returns {boolean} false if any of the plugins return false, else returns true.
         */
        notify: function (chart, hook, args) {
            var descriptors = this.descriptors(chart);
            var ilen = descriptors.length;
            var i, descriptor, plugin, params, method;

            for (i = 0; i < ilen; ++i) {
                descriptor = descriptors[i];
                plugin = descriptor.plugin;
                method = plugin[hook];
                if (typeof method === 'function') {
                    params = [chart].concat(args || []);
                    params.push(descriptor.options);
                    if (method.apply(plugin, params) === false) {
                        return false;
                    }
                }
            }

            return true;
        },

        /**
         * Returns descriptors of enabled plugins for the given chart.
         * @returns {object[]} [{ plugin, options }]
         * @private
         */
        descriptors: function (chart) {
            var cache = chart.$plugins || (chart.$plugins = {});
            if (cache.id === this._cacheId) {
                return cache.descriptors;
            }

            var plugins = [];
            var descriptors = [];
            var config = (chart && chart.config) || {};
            var options = (config.options && config.options.plugins) || {};

            this._plugins.concat(config.plugins || []).forEach(function (plugin) {
                var idx = plugins.indexOf(plugin);
                if (idx !== -1) {
                    return;
                }

                var id = plugin.id;
                var opts = options[id];
                if (opts === false) {
                    return;
                }

                if (opts === true) {
                    opts = helpers$1.clone(core_defaults.global.plugins[id]);
                }

                plugins.push(plugin);
                descriptors.push({
                    plugin: plugin,
                    options: opts || {}
                });
            });

            cache.descriptors = descriptors;
            cache.id = this._cacheId;
            return descriptors;
        },

        /**
         * Invalidates cache for the given chart: descriptors hold a reference on plugin option,
         * but in some cases, this reference can be changed by the user when updating options.
         * https://github.com/chartjs/Chart.js/issues/5111#issuecomment-355934167
         * @private
         */
        _invalidate: function (chart) {
            delete chart.$plugins;
        }
    };

    var core_scaleService = {
        // Scale registration object. Extensions can register new scale types (such as log or DB scales) and then
        // use the new chart options to grab the correct scale
        constructors: {},
        // Use a registration function so that we can move to an ES6 map when we no longer need to support
        // old browsers

        // Scale config defaults
        defaults: {},
        registerScaleType: function (type, scaleConstructor, scaleDefaults) {
            this.constructors[type] = scaleConstructor;
            this.defaults[type] = helpers$1.clone(scaleDefaults);
        },
        getScaleConstructor: function (type) {
            return this.constructors.hasOwnProperty(type) ? this.constructors[type] : undefined;
        },
        getScaleDefaults: function (type) {
            // Return the scale defaults merged with the global settings so that we always use the latest ones
            return this.defaults.hasOwnProperty(type) ? helpers$1.merge({}, [core_defaults.scale, this.defaults[type]]) : {};
        },
        updateScaleDefaults: function (type, additions) {
            var me = this;
            if (me.defaults.hasOwnProperty(type)) {
                me.defaults[type] = helpers$1.extend(me.defaults[type], additions);
            }
        },
        addScalesToLayout: function (chart) {
            // Adds each scale to the chart.boxes array to be sized accordingly
            helpers$1.each(chart.scales, function (scale) {
                // Set ILayoutItem parameters for backwards compatibility
                scale.fullWidth = scale.options.fullWidth;
                scale.position = scale.options.position;
                scale.weight = scale.options.weight;
                core_layouts.addBox(chart, scale);
            });
        }
    };

    var valueOrDefault$7 = helpers$1.valueOrDefault;

    core_defaults._set('global', {
        tooltips: {
            enabled: true,
            custom: null,
            mode: 'nearest',
            position: 'average',
            intersect: true,
            backgroundColor: 'rgba(0,0,0,0.8)',
            titleFontStyle: 'bold',
            titleSpacing: 2,
            titleMarginBottom: 6,
            titleFontColor: '#fff',
            titleAlign: 'left',
            bodySpacing: 2,
            bodyFontColor: '#fff',
            bodyAlign: 'left',
            footerFontStyle: 'bold',
            footerSpacing: 2,
            footerMarginTop: 6,
            footerFontColor: '#fff',
            footerAlign: 'left',
            yPadding: 6,
            xPadding: 6,
            caretPadding: 2,
            caretSize: 5,
            cornerRadius: 6,
            multiKeyBackground: '#fff',
            displayColors: true,
            borderColor: 'rgba(0,0,0,0)',
            borderWidth: 0,
            callbacks: {
                // Args are: (tooltipItems, data)
                beforeTitle: helpers$1.noop,
                title: function (tooltipItems, data) {
                    var title = '';
                    var labels = data.labels;
                    var labelCount = labels ? labels.length : 0;

                    if (tooltipItems.length > 0) {
                        var item = tooltipItems[0];
                        if (item.label) {
                            title = item.label;
                        } else if (item.xLabel) {
                            title = item.xLabel;
                        } else if (labelCount > 0 && item.index < labelCount) {
                            title = labels[item.index];
                        }
                    }

                    return title;
                },
                afterTitle: helpers$1.noop,

                // Args are: (tooltipItems, data)
                beforeBody: helpers$1.noop,

                // Args are: (tooltipItem, data)
                beforeLabel: helpers$1.noop,
                label: function (tooltipItem, data) {
                    var label = data.datasets[tooltipItem.datasetIndex].label || '';

                    if (label) {
                        label += ': ';
                    }
                    if (!helpers$1.isNullOrUndef(tooltipItem.value)) {
                        label += tooltipItem.value;
                    } else {
                        label += tooltipItem.yLabel;
                    }
                    return label;
                },
                labelColor: function (tooltipItem, chart) {
                    var meta = chart.getDatasetMeta(tooltipItem.datasetIndex);
                    var activeElement = meta.data[tooltipItem.index];
                    var view = activeElement._view;
                    return {
                        borderColor: view.borderColor,
                        backgroundColor: view.backgroundColor
                    };
                },
                labelTextColor: function () {
                    return this._options.bodyFontColor;
                },
                afterLabel: helpers$1.noop,

                // Args are: (tooltipItems, data)
                afterBody: helpers$1.noop,

                // Args are: (tooltipItems, data)
                beforeFooter: helpers$1.noop,
                footer: helpers$1.noop,
                afterFooter: helpers$1.noop
            }
        }
    });

    var positioners = {
        /**
         * Average mode places the tooltip at the average position of the elements shown
         * @function Chart.Tooltip.positioners.average
         * @param elements {ChartElement[]} the elements being displayed in the tooltip
         * @returns {object} tooltip position
         */
        average: function (elements) {
            if (!elements.length) {
                return false;
            }

            var i, len;
            var x = 0;
            var y = 0;
            var count = 0;

            for (i = 0, len = elements.length; i < len; ++i) {
                var el = elements[i];
                if (el && el.hasValue()) {
                    var pos = el.tooltipPosition();
                    x += pos.x;
                    y += pos.y;
                    ++count;
                }
            }

            return {
                x: x / count,
                y: y / count
            };
        },

        /**
         * Gets the tooltip position nearest of the item nearest to the event position
         * @function Chart.Tooltip.positioners.nearest
         * @param elements {Chart.Element[]} the tooltip elements
         * @param eventPosition {object} the position of the event in canvas coordinates
         * @returns {object} the tooltip position
         */
        nearest: function (elements, eventPosition) {
            var x = eventPosition.x;
            var y = eventPosition.y;
            var minDistance = Number.POSITIVE_INFINITY;
            var i, len, nearestElement;

            for (i = 0, len = elements.length; i < len; ++i) {
                var el = elements[i];
                if (el && el.hasValue()) {
                    var center = el.getCenterPoint();
                    var d = helpers$1.distanceBetweenPoints(eventPosition, center);

                    if (d < minDistance) {
                        minDistance = d;
                        nearestElement = el;
                    }
                }
            }

            if (nearestElement) {
                var tp = nearestElement.tooltipPosition();
                x = tp.x;
                y = tp.y;
            }

            return {
                x: x,
                y: y
            };
        }
    };

    // Helper to push or concat based on if the 2nd parameter is an array or not
    function pushOrConcat(base, toPush) {
        if (toPush) {
            if (helpers$1.isArray(toPush)) {
                // base = base.concat(toPush);
                Array.prototype.push.apply(base, toPush);
            } else {
                base.push(toPush);
            }
        }

        return base;
    }

    /**
     * Returns array of strings split by newline
     * @param {string} value - The value to split by newline.
     * @returns {string[]} value if newline present - Returned from String split() method
     * @function
     */
    function splitNewlines(str) {
        if ((typeof str === 'string' || str instanceof String) && str.indexOf('\n') > -1) {
            return str.split('\n');
        }
        return str;
    }


    /**
     * Private helper to create a tooltip item model
     * @param element - the chart element (point, arc, bar) to create the tooltip item for
     * @return new tooltip item
     */
    function createTooltipItem(element) {
        var xScale = element._xScale;
        var yScale = element._yScale || element._scale; // handle radar || polarArea charts
        var index = element._index;
        var datasetIndex = element._datasetIndex;
        var controller = element._chart.getDatasetMeta(datasetIndex).controller;
        var indexScale = controller._getIndexScale();
        var valueScale = controller._getValueScale();

        return {
            xLabel: xScale ? xScale.getLabelForIndex(index, datasetIndex) : '',
            yLabel: yScale ? yScale.getLabelForIndex(index, datasetIndex) : '',
            label: indexScale ? '' + indexScale.getLabelForIndex(index, datasetIndex) : '',
            value: valueScale ? '' + valueScale.getLabelForIndex(index, datasetIndex) : '',
            index: index,
            datasetIndex: datasetIndex,
            x: element._model.x,
            y: element._model.y
        };
    }

    /**
     * Helper to get the reset model for the tooltip
     * @param tooltipOpts {object} the tooltip options
     */
    function getBaseModel(tooltipOpts) {
        var globalDefaults = core_defaults.global;

        return {
            // Positioning
            xPadding: tooltipOpts.xPadding,
            yPadding: tooltipOpts.yPadding,
            xAlign: tooltipOpts.xAlign,
            yAlign: tooltipOpts.yAlign,

            // Body
            bodyFontColor: tooltipOpts.bodyFontColor,
            _bodyFontFamily: valueOrDefault$7(tooltipOpts.bodyFontFamily, globalDefaults.defaultFontFamily),
            _bodyFontStyle: valueOrDefault$7(tooltipOpts.bodyFontStyle, globalDefaults.defaultFontStyle),
            _bodyAlign: tooltipOpts.bodyAlign,
            bodyFontSize: valueOrDefault$7(tooltipOpts.bodyFontSize, globalDefaults.defaultFontSize),
            bodySpacing: tooltipOpts.bodySpacing,

            // Title
            titleFontColor: tooltipOpts.titleFontColor,
            _titleFontFamily: valueOrDefault$7(tooltipOpts.titleFontFamily, globalDefaults.defaultFontFamily),
            _titleFontStyle: valueOrDefault$7(tooltipOpts.titleFontStyle, globalDefaults.defaultFontStyle),
            titleFontSize: valueOrDefault$7(tooltipOpts.titleFontSize, globalDefaults.defaultFontSize),
            _titleAlign: tooltipOpts.titleAlign,
            titleSpacing: tooltipOpts.titleSpacing,
            titleMarginBottom: tooltipOpts.titleMarginBottom,

            // Footer
            footerFontColor: tooltipOpts.footerFontColor,
            _footerFontFamily: valueOrDefault$7(tooltipOpts.footerFontFamily, globalDefaults.defaultFontFamily),
            _footerFontStyle: valueOrDefault$7(tooltipOpts.footerFontStyle, globalDefaults.defaultFontStyle),
            footerFontSize: valueOrDefault$7(tooltipOpts.footerFontSize, globalDefaults.defaultFontSize),
            _footerAlign: tooltipOpts.footerAlign,
            footerSpacing: tooltipOpts.footerSpacing,
            footerMarginTop: tooltipOpts.footerMarginTop,

            // Appearance
            caretSize: tooltipOpts.caretSize,
            cornerRadius: tooltipOpts.cornerRadius,
            backgroundColor: tooltipOpts.backgroundColor,
            opacity: 0,
            legendColorBackground: tooltipOpts.multiKeyBackground,
            displayColors: tooltipOpts.displayColors,
            borderColor: tooltipOpts.borderColor,
            borderWidth: tooltipOpts.borderWidth
        };
    }

    /**
     * Get the size of the tooltip
     */
    function getTooltipSize(tooltip, model) {
        var ctx = tooltip._chart.ctx;

        var height = model.yPadding * 2; // Tooltip Padding
        var width = 0;

        // Count of all lines in the body
        var body = model.body;
        var combinedBodyLength = body.reduce(function (count, bodyItem) {
            return count + bodyItem.before.length + bodyItem.lines.length + bodyItem.after.length;
        }, 0);
        combinedBodyLength += model.beforeBody.length + model.afterBody.length;

        var titleLineCount = model.title.length;
        var footerLineCount = model.footer.length;
        var titleFontSize = model.titleFontSize;
        var bodyFontSize = model.bodyFontSize;
        var footerFontSize = model.footerFontSize;

        height += titleLineCount * titleFontSize; // Title Lines
        height += titleLineCount ? (titleLineCount - 1) * model.titleSpacing : 0; // Title Line Spacing
        height += titleLineCount ? model.titleMarginBottom : 0; // Title's bottom Margin
        height += combinedBodyLength * bodyFontSize; // Body Lines
        height += combinedBodyLength ? (combinedBodyLength - 1) * model.bodySpacing : 0; // Body Line Spacing
        height += footerLineCount ? model.footerMarginTop : 0; // Footer Margin
        height += footerLineCount * (footerFontSize); // Footer Lines
        height += footerLineCount ? (footerLineCount - 1) * model.footerSpacing : 0; // Footer Line Spacing

        // Title width
        var widthPadding = 0;
        var maxLineWidth = function (line) {
            width = Math.max(width, ctx.measureText(line).width + widthPadding);
        };

        ctx.font = helpers$1.fontString(titleFontSize, model._titleFontStyle, model._titleFontFamily);
        helpers$1.each(model.title, maxLineWidth);

        // Body width
        ctx.font = helpers$1.fontString(bodyFontSize, model._bodyFontStyle, model._bodyFontFamily);
        helpers$1.each(model.beforeBody.concat(model.afterBody), maxLineWidth);

        // Body lines may include some extra width due to the color box
        widthPadding = model.displayColors ? (bodyFontSize + 2) : 0;
        helpers$1.each(body, function (bodyItem) {
            helpers$1.each(bodyItem.before, maxLineWidth);
            helpers$1.each(bodyItem.lines, maxLineWidth);
            helpers$1.each(bodyItem.after, maxLineWidth);
        });

        // Reset back to 0
        widthPadding = 0;

        // Footer width
        ctx.font = helpers$1.fontString(footerFontSize, model._footerFontStyle, model._footerFontFamily);
        helpers$1.each(model.footer, maxLineWidth);

        // Add padding
        width += 2 * model.xPadding;

        return {
            width: width,
            height: height
        };
    }

    /**
     * Helper to get the alignment of a tooltip given the size
     */
    function determineAlignment(tooltip, size) {
        var model = tooltip._model;
        var chart = tooltip._chart;
        var chartArea = tooltip._chart.chartArea;
        var xAlign = 'center';
        var yAlign = 'center';

        if (model.y < size.height) {
            yAlign = 'top';
        } else if (model.y > (chart.height - size.height)) {
            yAlign = 'bottom';
        }

        var lf, rf; // functions to determine left, right alignment
        var olf, orf; // functions to determine if left/right alignment causes tooltip to go outside chart
        var yf; // function to get the y alignment if the tooltip goes outside of the left or right edges
        var midX = (chartArea.left + chartArea.right) / 2;
        var midY = (chartArea.top + chartArea.bottom) / 2;

        if (yAlign === 'center') {
            lf = function (x) {
                return x <= midX;
            };
            rf = function (x) {
                return x > midX;
            };
        } else {
            lf = function (x) {
                return x <= (size.width / 2);
            };
            rf = function (x) {
                return x >= (chart.width - (size.width / 2));
            };
        }

        olf = function (x) {
            return x + size.width + model.caretSize + model.caretPadding > chart.width;
        };
        orf = function (x) {
            return x - size.width - model.caretSize - model.caretPadding < 0;
        };
        yf = function (y) {
            return y <= midY ? 'top' : 'bottom';
        };

        if (lf(model.x)) {
            xAlign = 'left';

            // Is tooltip too wide and goes over the right side of the chart.?
            if (olf(model.x)) {
                xAlign = 'center';
                yAlign = yf(model.y);
            }
        } else if (rf(model.x)) {
            xAlign = 'right';

            // Is tooltip too wide and goes outside left edge of canvas?
            if (orf(model.x)) {
                xAlign = 'center';
                yAlign = yf(model.y);
            }
        }

        var opts = tooltip._options;
        return {
            xAlign: opts.xAlign ? opts.xAlign : xAlign,
            yAlign: opts.yAlign ? opts.yAlign : yAlign
        };
    }

    /**
     * Helper to get the location a tooltip needs to be placed at given the initial position (via the vm) and the size and alignment
     */
    function getBackgroundPoint(vm, size, alignment, chart) {
        // Background Position
        var x = vm.x;
        var y = vm.y;

        var caretSize = vm.caretSize;
        var caretPadding = vm.caretPadding;
        var cornerRadius = vm.cornerRadius;
        var xAlign = alignment.xAlign;
        var yAlign = alignment.yAlign;
        var paddingAndSize = caretSize + caretPadding;
        var radiusAndPadding = cornerRadius + caretPadding;

        if (xAlign === 'right') {
            x -= size.width;
        } else if (xAlign === 'center') {
            x -= (size.width / 2);
            if (x + size.width > chart.width) {
                x = chart.width - size.width;
            }
            if (x < 0) {
                x = 0;
            }
        }

        if (yAlign === 'top') {
            y += paddingAndSize;
        } else if (yAlign === 'bottom') {
            y -= size.height + paddingAndSize;
        } else {
            y -= (size.height / 2);
        }

        if (yAlign === 'center') {
            if (xAlign === 'left') {
                x += paddingAndSize;
            } else if (xAlign === 'right') {
                x -= paddingAndSize;
            }
        } else if (xAlign === 'left') {
            x -= radiusAndPadding;
        } else if (xAlign === 'right') {
            x += radiusAndPadding;
        }

        return {
            x: x,
            y: y
        };
    }

    function getAlignedX(vm, align) {
        return align === 'center'
            ? vm.x + vm.width / 2
            : align === 'right'
                ? vm.x + vm.width - vm.xPadding
                : vm.x + vm.xPadding;
    }

    /**
     * Helper to build before and after body lines
     */
    function getBeforeAfterBodyLines(callback) {
        return pushOrConcat([], splitNewlines(callback));
    }

    var exports$3 = core_element.extend({
        initialize: function () {
            this._model = getBaseModel(this._options);
            this._lastActive = [];
        },

        // Get the title
        // Args are: (tooltipItem, data)
        getTitle: function () {
            var me = this;
            var opts = me._options;
            var callbacks = opts.callbacks;

            var beforeTitle = callbacks.beforeTitle.apply(me, arguments);
            var title = callbacks.title.apply(me, arguments);
            var afterTitle = callbacks.afterTitle.apply(me, arguments);

            var lines = [];
            lines = pushOrConcat(lines, splitNewlines(beforeTitle));
            lines = pushOrConcat(lines, splitNewlines(title));
            lines = pushOrConcat(lines, splitNewlines(afterTitle));

            return lines;
        },

        // Args are: (tooltipItem, data)
        getBeforeBody: function () {
            return getBeforeAfterBodyLines(this._options.callbacks.beforeBody.apply(this, arguments));
        },

        // Args are: (tooltipItem, data)
        getBody: function (tooltipItems, data) {
            var me = this;
            var callbacks = me._options.callbacks;
            var bodyItems = [];

            helpers$1.each(tooltipItems, function (tooltipItem) {
                var bodyItem = {
                    before: [],
                    lines: [],
                    after: []
                };
                pushOrConcat(bodyItem.before, splitNewlines(callbacks.beforeLabel.call(me, tooltipItem, data)));
                pushOrConcat(bodyItem.lines, callbacks.label.call(me, tooltipItem, data));
                pushOrConcat(bodyItem.after, splitNewlines(callbacks.afterLabel.call(me, tooltipItem, data)));

                bodyItems.push(bodyItem);
            });

            return bodyItems;
        },

        // Args are: (tooltipItem, data)
        getAfterBody: function () {
            return getBeforeAfterBodyLines(this._options.callbacks.afterBody.apply(this, arguments));
        },

        // Get the footer and beforeFooter and afterFooter lines
        // Args are: (tooltipItem, data)
        getFooter: function () {
            var me = this;
            var callbacks = me._options.callbacks;

            var beforeFooter = callbacks.beforeFooter.apply(me, arguments);
            var footer = callbacks.footer.apply(me, arguments);
            var afterFooter = callbacks.afterFooter.apply(me, arguments);

            var lines = [];
            lines = pushOrConcat(lines, splitNewlines(beforeFooter));
            lines = pushOrConcat(lines, splitNewlines(footer));
            lines = pushOrConcat(lines, splitNewlines(afterFooter));

            return lines;
        },

        update: function (changed) {
            var me = this;
            var opts = me._options;

            // Need to regenerate the model because its faster than using extend and it is necessary due to the optimization in Chart.Element.transition
            // that does _view = _model if ease === 1. This causes the 2nd tooltip update to set properties in both the view and model at the same time
            // which breaks any animations.
            var existingModel = me._model;
            var model = me._model = getBaseModel(opts);
            var active = me._active;

            var data = me._data;

            // In the case where active.length === 0 we need to keep these at existing values for good animations
            var alignment = {
                xAlign: existingModel.xAlign,
                yAlign: existingModel.yAlign
            };
            var backgroundPoint = {
                x: existingModel.x,
                y: existingModel.y
            };
            var tooltipSize = {
                width: existingModel.width,
                height: existingModel.height
            };
            var tooltipPosition = {
                x: existingModel.caretX,
                y: existingModel.caretY
            };

            var i, len;

            if (active.length) {
                model.opacity = 1;

                var labelColors = [];
                var labelTextColors = [];
                tooltipPosition = positioners[opts.position].call(me, active, me._eventPosition);

                var tooltipItems = [];
                for (i = 0, len = active.length; i < len; ++i) {
                    tooltipItems.push(createTooltipItem(active[i]));
                }

                // If the user provided a filter function, use it to modify the tooltip items
                if (opts.filter) {
                    tooltipItems = tooltipItems.filter(function (a) {
                        return opts.filter(a, data);
                    });
                }

                // If the user provided a sorting function, use it to modify the tooltip items
                if (opts.itemSort) {
                    tooltipItems = tooltipItems.sort(function (a, b) {
                        return opts.itemSort(a, b, data);
                    });
                }

                // Determine colors for boxes
                helpers$1.each(tooltipItems, function (tooltipItem) {
                    labelColors.push(opts.callbacks.labelColor.call(me, tooltipItem, me._chart));
                    labelTextColors.push(opts.callbacks.labelTextColor.call(me, tooltipItem, me._chart));
                });


                // Build the Text Lines
                model.title = me.getTitle(tooltipItems, data);
                model.beforeBody = me.getBeforeBody(tooltipItems, data);
                model.body = me.getBody(tooltipItems, data);
                model.afterBody = me.getAfterBody(tooltipItems, data);
                model.footer = me.getFooter(tooltipItems, data);

                // Initial positioning and colors
                model.x = tooltipPosition.x;
                model.y = tooltipPosition.y;
                model.caretPadding = opts.caretPadding;
                model.labelColors = labelColors;
                model.labelTextColors = labelTextColors;

                // data points
                model.dataPoints = tooltipItems;

                // We need to determine alignment of the tooltip
                tooltipSize = getTooltipSize(this, model);
                alignment = determineAlignment(this, tooltipSize);
                // Final Size and Position
                backgroundPoint = getBackgroundPoint(model, tooltipSize, alignment, me._chart);
            } else {
                model.opacity = 0;
            }

            model.xAlign = alignment.xAlign;
            model.yAlign = alignment.yAlign;
            model.x = backgroundPoint.x;
            model.y = backgroundPoint.y;
            model.width = tooltipSize.width;
            model.height = tooltipSize.height;

            // Point where the caret on the tooltip points to
            model.caretX = tooltipPosition.x;
            model.caretY = tooltipPosition.y;

            me._model = model;

            if (changed && opts.custom) {
                opts.custom.call(me, model);
            }

            return me;
        },

        drawCaret: function (tooltipPoint, size) {
            var ctx = this._chart.ctx;
            var vm = this._view;
            var caretPosition = this.getCaretPosition(tooltipPoint, size, vm);

            ctx.lineTo(caretPosition.x1, caretPosition.y1);
            ctx.lineTo(caretPosition.x2, caretPosition.y2);
            ctx.lineTo(caretPosition.x3, caretPosition.y3);
        },
        getCaretPosition: function (tooltipPoint, size, vm) {
            var x1, x2, x3, y1, y2, y3;
            var caretSize = vm.caretSize;
            var cornerRadius = vm.cornerRadius;
            var xAlign = vm.xAlign;
            var yAlign = vm.yAlign;
            var ptX = tooltipPoint.x;
            var ptY = tooltipPoint.y;
            var width = size.width;
            var height = size.height;

            if (yAlign === 'center') {
                y2 = ptY + (height / 2);

                if (xAlign === 'left') {
                    x1 = ptX;
                    x2 = x1 - caretSize;
                    x3 = x1;

                    y1 = y2 + caretSize;
                    y3 = y2 - caretSize;
                } else {
                    x1 = ptX + width;
                    x2 = x1 + caretSize;
                    x3 = x1;

                    y1 = y2 - caretSize;
                    y3 = y2 + caretSize;
                }
            } else {
                if (xAlign === 'left') {
                    x2 = ptX + cornerRadius + (caretSize);
                    x1 = x2 - caretSize;
                    x3 = x2 + caretSize;
                } else if (xAlign === 'right') {
                    x2 = ptX + width - cornerRadius - caretSize;
                    x1 = x2 - caretSize;
                    x3 = x2 + caretSize;
                } else {
                    x2 = vm.caretX;
                    x1 = x2 - caretSize;
                    x3 = x2 + caretSize;
                }
                if (yAlign === 'top') {
                    y1 = ptY;
                    y2 = y1 - caretSize;
                    y3 = y1;
                } else {
                    y1 = ptY + height;
                    y2 = y1 + caretSize;
                    y3 = y1;
                    // invert drawing order
                    var tmp = x3;
                    x3 = x1;
                    x1 = tmp;
                }
            }
            return { x1: x1, x2: x2, x3: x3, y1: y1, y2: y2, y3: y3 };
        },

        drawTitle: function (pt, vm, ctx) {
            var title = vm.title;

            if (title.length) {
                pt.x = getAlignedX(vm, vm._titleAlign);

                ctx.textAlign = vm._titleAlign;
                ctx.textBaseline = 'top';

                var titleFontSize = vm.titleFontSize;
                var titleSpacing = vm.titleSpacing;

                ctx.fillStyle = vm.titleFontColor;
                ctx.font = helpers$1.fontString(titleFontSize, vm._titleFontStyle, vm._titleFontFamily);

                var i, len;
                for (i = 0, len = title.length; i < len; ++i) {
                    ctx.fillText(title[i], pt.x, pt.y);
                    pt.y += titleFontSize + titleSpacing; // Line Height and spacing

                    if (i + 1 === title.length) {
                        pt.y += vm.titleMarginBottom - titleSpacing; // If Last, add margin, remove spacing
                    }
                }
            }
        },

        drawBody: function (pt, vm, ctx) {
            var bodyFontSize = vm.bodyFontSize;
            var bodySpacing = vm.bodySpacing;
            var bodyAlign = vm._bodyAlign;
            var body = vm.body;
            var drawColorBoxes = vm.displayColors;
            var labelColors = vm.labelColors;
            var xLinePadding = 0;
            var colorX = drawColorBoxes ? getAlignedX(vm, 'left') : 0;
            var textColor;

            ctx.textAlign = bodyAlign;
            ctx.textBaseline = 'top';
            ctx.font = helpers$1.fontString(bodyFontSize, vm._bodyFontStyle, vm._bodyFontFamily);

            pt.x = getAlignedX(vm, bodyAlign);

            // Before Body
            var fillLineOfText = function (line) {
                ctx.fillText(line, pt.x + xLinePadding, pt.y);
                pt.y += bodyFontSize + bodySpacing;
            };

            // Before body lines
            ctx.fillStyle = vm.bodyFontColor;
            helpers$1.each(vm.beforeBody, fillLineOfText);

            xLinePadding = drawColorBoxes && bodyAlign !== 'right'
                ? bodyAlign === 'center' ? (bodyFontSize / 2 + 1) : (bodyFontSize + 2)
                : 0;

            // Draw body lines now
            helpers$1.each(body, function (bodyItem, i) {
                textColor = vm.labelTextColors[i];
                ctx.fillStyle = textColor;
                helpers$1.each(bodyItem.before, fillLineOfText);

                helpers$1.each(bodyItem.lines, function (line) {
                    // Draw Legend-like boxes if needed
                    if (drawColorBoxes) {
                        // Fill a white rect so that colours merge nicely if the opacity is < 1
                        ctx.fillStyle = vm.legendColorBackground;
                        ctx.fillRect(colorX, pt.y, bodyFontSize, bodyFontSize);

                        // Border
                        ctx.lineWidth = 1;
                        ctx.strokeStyle = labelColors[i].borderColor;
                        ctx.strokeRect(colorX, pt.y, bodyFontSize, bodyFontSize);

                        // Inner square
                        ctx.fillStyle = labelColors[i].backgroundColor;
                        ctx.fillRect(colorX + 1, pt.y + 1, bodyFontSize - 2, bodyFontSize - 2);
                        ctx.fillStyle = textColor;
                    }

                    fillLineOfText(line);
                });

                helpers$1.each(bodyItem.after, fillLineOfText);
            });

            // Reset back to 0 for after body
            xLinePadding = 0;

            // After body lines
            helpers$1.each(vm.afterBody, fillLineOfText);
            pt.y -= bodySpacing; // Remove last body spacing
        },

        drawFooter: function (pt, vm, ctx) {
            var footer = vm.footer;

            if (footer.length) {
                pt.x = getAlignedX(vm, vm._footerAlign);
                pt.y += vm.footerMarginTop;

                ctx.textAlign = vm._footerAlign;
                ctx.textBaseline = 'top';

                ctx.fillStyle = vm.footerFontColor;
                ctx.font = helpers$1.fontString(vm.footerFontSize, vm._footerFontStyle, vm._footerFontFamily);

                helpers$1.each(footer, function (line) {
                    ctx.fillText(line, pt.x, pt.y);
                    pt.y += vm.footerFontSize + vm.footerSpacing;
                });
            }
        },

        drawBackground: function (pt, vm, ctx, tooltipSize) {
            ctx.fillStyle = vm.backgroundColor;
            ctx.strokeStyle = vm.borderColor;
            ctx.lineWidth = vm.borderWidth;
            var xAlign = vm.xAlign;
            var yAlign = vm.yAlign;
            var x = pt.x;
            var y = pt.y;
            var width = tooltipSize.width;
            var height = tooltipSize.height;
            var radius = vm.cornerRadius;

            ctx.beginPath();
            ctx.moveTo(x + radius, y);
            if (yAlign === 'top') {
                this.drawCaret(pt, tooltipSize);
            }
            ctx.lineTo(x + width - radius, y);
            ctx.quadraticCurveTo(x + width, y, x + width, y + radius);
            if (yAlign === 'center' && xAlign === 'right') {
                this.drawCaret(pt, tooltipSize);
            }
            ctx.lineTo(x + width, y + height - radius);
            ctx.quadraticCurveTo(x + width, y + height, x + width - radius, y + height);
            if (yAlign === 'bottom') {
                this.drawCaret(pt, tooltipSize);
            }
            ctx.lineTo(x + radius, y + height);
            ctx.quadraticCurveTo(x, y + height, x, y + height - radius);
            if (yAlign === 'center' && xAlign === 'left') {
                this.drawCaret(pt, tooltipSize);
            }
            ctx.lineTo(x, y + radius);
            ctx.quadraticCurveTo(x, y, x + radius, y);
            ctx.closePath();

            ctx.fill();

            if (vm.borderWidth > 0) {
                ctx.stroke();
            }
        },

        draw: function () {
            var ctx = this._chart.ctx;
            var vm = this._view;

            if (vm.opacity === 0) {
                return;
            }

            var tooltipSize = {
                width: vm.width,
                height: vm.height
            };
            var pt = {
                x: vm.x,
                y: vm.y
            };

            // IE11/Edge does not like very small opacities, so snap to 0
            var opacity = Math.abs(vm.opacity < 1e-3) ? 0 : vm.opacity;

            // Truthy/falsey value for empty tooltip
            var hasTooltipContent = vm.title.length || vm.beforeBody.length || vm.body.length || vm.afterBody.length || vm.footer.length;

            if (this._options.enabled && hasTooltipContent) {
                ctx.save();
                ctx.globalAlpha = opacity;

                // Draw Background
                this.drawBackground(pt, vm, ctx, tooltipSize);

                // Draw Title, Body, and Footer
                pt.y += vm.yPadding;

                // Titles
                this.drawTitle(pt, vm, ctx);

                // Body
                this.drawBody(pt, vm, ctx);

                // Footer
                this.drawFooter(pt, vm, ctx);

                ctx.restore();
            }
        },

        /**
         * Handle an event
         * @private
         * @param {IEvent} event - The event to handle
         * @returns {boolean} true if the tooltip changed
         */
        handleEvent: function (e) {
            var me = this;
            var options = me._options;
            var changed = false;

            me._lastActive = me._lastActive || [];

            // Find Active Elements for tooltips
            if (e.type === 'mouseout') {
                me._active = [];
            } else {
                me._active = me._chart.getElementsAtEventForMode(e, options.mode, options);
            }

            // Remember Last Actives
            changed = !helpers$1.arrayEquals(me._active, me._lastActive);

            // Only handle target event on tooltip change
            if (changed) {
                me._lastActive = me._active;

                if (options.enabled || options.custom) {
                    me._eventPosition = {
                        x: e.x,
                        y: e.y
                    };

                    me.update(true);
                    me.pivot();
                }
            }

            return changed;
        }
    });

    /**
     * @namespace Chart.Tooltip.positioners
     */
    var positioners_1 = positioners;

    var core_tooltip = exports$3;
    core_tooltip.positioners = positioners_1;

    var valueOrDefault$8 = helpers$1.valueOrDefault;

    core_defaults._set('global', {
        elements: {},
        events: [
            'mousemove',
            'mouseout',
            'click',
            'touchstart',
            'touchmove'
        ],
        hover: {
            onHover: null,
            mode: 'nearest',
            intersect: true,
            animationDuration: 400
        },
        onClick: null,
        maintainAspectRatio: true,
        responsive: true,
        responsiveAnimationDuration: 0
    });

    /**
     * Recursively merge the given config objects representing the `scales` option
     * by incorporating scale defaults in `xAxes` and `yAxes` array items, then
     * returns a deep copy of the result, thus doesn't alter inputs.
     */
    function mergeScaleConfig(/* config objects ... */) {
        return helpers$1.merge({}, [].slice.call(arguments), {
            merger: function (key, target, source, options) {
                if (key === 'xAxes' || key === 'yAxes') {
                    var slen = source[key].length;
                    var i, type, scale;

                    if (!target[key]) {
                        target[key] = [];
                    }

                    for (i = 0; i < slen; ++i) {
                        scale = source[key][i];
                        type = valueOrDefault$8(scale.type, key === 'xAxes' ? 'category' : 'linear');

                        if (i >= target[key].length) {
                            target[key].push({});
                        }

                        if (!target[key][i].type || (scale.type && scale.type !== target[key][i].type)) {
                            // new/untyped scale or type changed: let's apply the new defaults
                            // then merge source scale to correctly overwrite the defaults.
                            helpers$1.merge(target[key][i], [core_scaleService.getScaleDefaults(type), scale]);
                        } else {
                            // scales type are the same
                            helpers$1.merge(target[key][i], scale);
                        }
                    }
                } else {
                    helpers$1._merger(key, target, source, options);
                }
            }
        });
    }

    /**
     * Recursively merge the given config objects as the root options by handling
     * default scale options for the `scales` and `scale` properties, then returns
     * a deep copy of the result, thus doesn't alter inputs.
     */
    function mergeConfig(/* config objects ... */) {
        return helpers$1.merge({}, [].slice.call(arguments), {
            merger: function (key, target, source, options) {
                var tval = target[key] || {};
                var sval = source[key];

                if (key === 'scales') {
                    // scale config merging is complex. Add our own function here for that
                    target[key] = mergeScaleConfig(tval, sval);
                } else if (key === 'scale') {
                    // used in polar area & radar charts since there is only one scale
                    target[key] = helpers$1.merge(tval, [core_scaleService.getScaleDefaults(sval.type), sval]);
                } else {
                    helpers$1._merger(key, target, source, options);
                }
            }
        });
    }

    function initConfig(config) {
        config = config || {};

        // Do NOT use mergeConfig for the data object because this method merges arrays
        // and so would change references to labels and datasets, preventing data updates.
        var data = config.data = config.data || {};
        data.datasets = data.datasets || [];
        data.labels = data.labels || [];

        config.options = mergeConfig(
            core_defaults.global,
            core_defaults[config.type],
            config.options || {});

        return config;
    }

    function updateConfig(chart) {
        var newOptions = chart.options;

        helpers$1.each(chart.scales, function (scale) {
            core_layouts.removeBox(chart, scale);
        });

        newOptions = mergeConfig(
            core_defaults.global,
            core_defaults[chart.config.type],
            newOptions);

        chart.options = chart.config.options = newOptions;
        chart.ensureScalesHaveIDs();
        chart.buildOrUpdateScales();

        // Tooltip
        chart.tooltip._options = newOptions.tooltips;
        chart.tooltip.initialize();
    }

    function positionIsHorizontal(position) {
        return position === 'top' || position === 'bottom';
    }

    var Chart = function (item, config) {
        this.construct(item, config);
        return this;
    };

    helpers$1.extend(Chart.prototype, /** @lends Chart */ {
        /**
         * @private
         */
        construct: function (item, config) {
            var me = this;

            config = initConfig(config);

            var context = platform.acquireContext(item, config);
            var canvas = context && context.canvas;
            var height = canvas && canvas.height;
            var width = canvas && canvas.width;

            me.id = helpers$1.uid();
            me.ctx = context;
            me.canvas = canvas;
            me.config = config;
            me.width = width;
            me.height = height;
            me.aspectRatio = height ? width / height : null;
            me.options = config.options;
            me._bufferedRender = false;

            /**
             * Provided for backward compatibility, Chart and Chart.Controller have been merged,
             * the "instance" still need to be defined since it might be called from plugins.
             * @prop Chart#chart
             * @deprecated since version 2.6.0
             * @todo remove at version 3
             * @private
             */
            me.chart = me;
            me.controller = me; // chart.chart.controller #inception

            // Add the chart instance to the global namespace
            Chart.instances[me.id] = me;

            // Define alias to the config data: `chart.data === chart.config.data`
            Object.defineProperty(me, 'data', {
                get: function () {
                    return me.config.data;
                },
                set: function (value) {
                    me.config.data = value;
                }
            });

            if (!context || !canvas) {
                // The given item is not a compatible context2d element, let's return before finalizing
                // the chart initialization but after setting basic chart / controller properties that
                // can help to figure out that the chart is not valid (e.g chart.canvas !== null);
                // https://github.com/chartjs/Chart.js/issues/2807
                console.error("Failed to create chart: can't acquire context from the given item");
                return;
            }

            me.initialize();
            me.update();
        },

        /**
         * @private
         */
        initialize: function () {
            var me = this;

            // Before init plugin notification
            core_plugins.notify(me, 'beforeInit');

            helpers$1.retinaScale(me, me.options.devicePixelRatio);

            me.bindEvents();

            if (me.options.responsive) {
                // Initial resize before chart draws (must be silent to preserve initial animations).
                me.resize(true);
            }

            // Make sure scales have IDs and are built before we build any controllers.
            me.ensureScalesHaveIDs();
            me.buildOrUpdateScales();
            me.initToolTip();

            // After init plugin notification
            core_plugins.notify(me, 'afterInit');

            return me;
        },

        clear: function () {
            helpers$1.canvas.clear(this);
            return this;
        },

        stop: function () {
            // Stops any current animation loop occurring
            core_animations.cancelAnimation(this);
            return this;
        },

        resize: function (silent) {
            var me = this;
            var options = me.options;
            var canvas = me.canvas;
            var aspectRatio = (options.maintainAspectRatio && me.aspectRatio) || null;

            // the canvas render width and height will be casted to integers so make sure that
            // the canvas display style uses the same integer values to avoid blurring effect.

            // Set to 0 instead of canvas.size because the size defaults to 300x150 if the element is collapsed
            var newWidth = Math.max(0, Math.floor(helpers$1.getMaximumWidth(canvas)));
            var newHeight = Math.max(0, Math.floor(aspectRatio ? newWidth / aspectRatio : helpers$1.getMaximumHeight(canvas)));

            if (me.width === newWidth && me.height === newHeight) {
                return;
            }

            canvas.width = me.width = newWidth;
            canvas.height = me.height = newHeight;
            canvas.style.width = newWidth + 'px';
            canvas.style.height = newHeight + 'px';

            helpers$1.retinaScale(me, options.devicePixelRatio);

            if (!silent) {
                // Notify any plugins about the resize
                var newSize = { width: newWidth, height: newHeight };
                core_plugins.notify(me, 'resize', [newSize]);

                // Notify of resize
                if (options.onResize) {
                    options.onResize(me, newSize);
                }

                me.stop();
                me.update({
                    duration: options.responsiveAnimationDuration
                });
            }
        },

        ensureScalesHaveIDs: function () {
            var options = this.options;
            var scalesOptions = options.scales || {};
            var scaleOptions = options.scale;

            helpers$1.each(scalesOptions.xAxes, function (xAxisOptions, index) {
                xAxisOptions.id = xAxisOptions.id || ('x-axis-' + index);
            });

            helpers$1.each(scalesOptions.yAxes, function (yAxisOptions, index) {
                yAxisOptions.id = yAxisOptions.id || ('y-axis-' + index);
            });

            if (scaleOptions) {
                scaleOptions.id = scaleOptions.id || 'scale';
            }
        },

        /**
         * Builds a map of scale ID to scale object for future lookup.
         */
        buildOrUpdateScales: function () {
            var me = this;
            var options = me.options;
            var scales = me.scales || {};
            var items = [];
            var updated = Object.keys(scales).reduce(function (obj, id) {
                obj[id] = false;
                return obj;
            }, {});

            if (options.scales) {
                items = items.concat(
                    (options.scales.xAxes || []).map(function (xAxisOptions) {
                        return { options: xAxisOptions, dtype: 'category', dposition: 'bottom' };
                    }),
                    (options.scales.yAxes || []).map(function (yAxisOptions) {
                        return { options: yAxisOptions, dtype: 'linear', dposition: 'left' };
                    })
                );
            }

            if (options.scale) {
                items.push({
                    options: options.scale,
                    dtype: 'radialLinear',
                    isDefault: true,
                    dposition: 'chartArea'
                });
            }

            helpers$1.each(items, function (item) {
                var scaleOptions = item.options;
                var id = scaleOptions.id;
                var scaleType = valueOrDefault$8(scaleOptions.type, item.dtype);

                if (positionIsHorizontal(scaleOptions.position) !== positionIsHorizontal(item.dposition)) {
                    scaleOptions.position = item.dposition;
                }

                updated[id] = true;
                var scale = null;
                if (id in scales && scales[id].type === scaleType) {
                    scale = scales[id];
                    scale.options = scaleOptions;
                    scale.ctx = me.ctx;
                    scale.chart = me;
                } else {
                    var scaleClass = core_scaleService.getScaleConstructor(scaleType);
                    if (!scaleClass) {
                        return;
                    }
                    scale = new scaleClass({
                        id: id,
                        type: scaleType,
                        options: scaleOptions,
                        ctx: me.ctx,
                        chart: me
                    });
                    scales[scale.id] = scale;
                }

                scale.mergeTicksOptions();

                // TODO(SB): I think we should be able to remove this custom case (options.scale)
                // and consider it as a regular scale part of the "scales"" map only! This would
                // make the logic easier and remove some useless? custom code.
                if (item.isDefault) {
                    me.scale = scale;
                }
            });
            // clear up discarded scales
            helpers$1.each(updated, function (hasUpdated, id) {
                if (!hasUpdated) {
                    delete scales[id];
                }
            });

            me.scales = scales;

            core_scaleService.addScalesToLayout(this);
        },

        buildOrUpdateControllers: function () {
            var me = this;
            var newControllers = [];

            helpers$1.each(me.data.datasets, function (dataset, datasetIndex) {
                var meta = me.getDatasetMeta(datasetIndex);
                var type = dataset.type || me.config.type;

                if (meta.type && meta.type !== type) {
                    me.destroyDatasetMeta(datasetIndex);
                    meta = me.getDatasetMeta(datasetIndex);
                }
                meta.type = type;

                if (meta.controller) {
                    meta.controller.updateIndex(datasetIndex);
                    meta.controller.linkScales();
                } else {
                    var ControllerClass = controllers[meta.type];
                    if (ControllerClass === undefined) {
                        throw new Error('"' + meta.type + '" is not a chart type.');
                    }

                    meta.controller = new ControllerClass(me, datasetIndex);
                    newControllers.push(meta.controller);
                }
            }, me);

            return newControllers;
        },

        /**
         * Reset the elements of all datasets
         * @private
         */
        resetElements: function () {
            var me = this;
            helpers$1.each(me.data.datasets, function (dataset, datasetIndex) {
                me.getDatasetMeta(datasetIndex).controller.reset();
            }, me);
        },

        /**
        * Resets the chart back to it's state before the initial animation
        */
        reset: function () {
            this.resetElements();
            this.tooltip.initialize();
        },

        update: function (config) {
            var me = this;

            if (!config || typeof config !== 'object') {
                // backwards compatibility
                config = {
                    duration: config,
                    lazy: arguments[1]
                };
            }

            updateConfig(me);

            // plugins options references might have change, let's invalidate the cache
            // https://github.com/chartjs/Chart.js/issues/5111#issuecomment-355934167
            core_plugins._invalidate(me);

            if (core_plugins.notify(me, 'beforeUpdate') === false) {
                return;
            }

            // In case the entire data object changed
            me.tooltip._data = me.data;

            // Make sure dataset controllers are updated and new controllers are reset
            var newControllers = me.buildOrUpdateControllers();

            // Make sure all dataset controllers have correct meta data counts
            helpers$1.each(me.data.datasets, function (dataset, datasetIndex) {
                me.getDatasetMeta(datasetIndex).controller.buildOrUpdateElements();
            }, me);

            me.updateLayout();

            // Can only reset the new controllers after the scales have been updated
            if (me.options.animation && me.options.animation.duration) {
                helpers$1.each(newControllers, function (controller) {
                    controller.reset();
                });
            }

            me.updateDatasets();

            // Need to reset tooltip in case it is displayed with elements that are removed
            // after update.
            me.tooltip.initialize();

            // Last active contains items that were previously in the tooltip.
            // When we reset the tooltip, we need to clear it
            me.lastActive = [];

            // Do this before render so that any plugins that need final scale updates can use it
            core_plugins.notify(me, 'afterUpdate');

            if (me._bufferedRender) {
                me._bufferedRequest = {
                    duration: config.duration,
                    easing: config.easing,
                    lazy: config.lazy
                };
            } else {
                me.render(config);
            }
        },

        /**
         * Updates the chart layout unless a plugin returns `false` to the `beforeLayout`
         * hook, in which case, plugins will not be called on `afterLayout`.
         * @private
         */
        updateLayout: function () {
            var me = this;

            if (core_plugins.notify(me, 'beforeLayout') === false) {
                return;
            }

            core_layouts.update(this, this.width, this.height);

            /**
             * Provided for backward compatibility, use `afterLayout` instead.
             * @method IPlugin#afterScaleUpdate
             * @deprecated since version 2.5.0
             * @todo remove at version 3
             * @private
             */
            core_plugins.notify(me, 'afterScaleUpdate');
            core_plugins.notify(me, 'afterLayout');
        },

        /**
         * Updates all datasets unless a plugin returns `false` to the `beforeDatasetsUpdate`
         * hook, in which case, plugins will not be called on `afterDatasetsUpdate`.
         * @private
         */
        updateDatasets: function () {
            var me = this;

            if (core_plugins.notify(me, 'beforeDatasetsUpdate') === false) {
                return;
            }

            for (var i = 0, ilen = me.data.datasets.length; i < ilen; ++i) {
                me.updateDataset(i);
            }

            core_plugins.notify(me, 'afterDatasetsUpdate');
        },

        /**
         * Updates dataset at index unless a plugin returns `false` to the `beforeDatasetUpdate`
         * hook, in which case, plugins will not be called on `afterDatasetUpdate`.
         * @private
         */
        updateDataset: function (index) {
            var me = this;
            var meta = me.getDatasetMeta(index);
            var args = {
                meta: meta,
                index: index
            };

            if (core_plugins.notify(me, 'beforeDatasetUpdate', [args]) === false) {
                return;
            }

            meta.controller.update();

            core_plugins.notify(me, 'afterDatasetUpdate', [args]);
        },

        render: function (config) {
            var me = this;

            if (!config || typeof config !== 'object') {
                // backwards compatibility
                config = {
                    duration: config,
                    lazy: arguments[1]
                };
            }

            var animationOptions = me.options.animation;
            var duration = valueOrDefault$8(config.duration, animationOptions && animationOptions.duration);
            var lazy = config.lazy;

            if (core_plugins.notify(me, 'beforeRender') === false) {
                return;
            }

            var onComplete = function (animation) {
                core_plugins.notify(me, 'afterRender');
                helpers$1.callback(animationOptions && animationOptions.onComplete, [animation], me);
            };

            if (animationOptions && duration) {
                var animation = new core_animation({
                    numSteps: duration / 16.66, // 60 fps
                    easing: config.easing || animationOptions.easing,

                    render: function (chart, animationObject) {
                        var easingFunction = helpers$1.easing.effects[animationObject.easing];
                        var currentStep = animationObject.currentStep;
                        var stepDecimal = currentStep / animationObject.numSteps;

                        chart.draw(easingFunction(stepDecimal), stepDecimal, currentStep);
                    },

                    onAnimationProgress: animationOptions.onProgress,
                    onAnimationComplete: onComplete
                });

                core_animations.addAnimation(me, animation, duration, lazy);
            } else {
                me.draw();

                // See https://github.com/chartjs/Chart.js/issues/3781
                onComplete(new core_animation({ numSteps: 0, chart: me }));
            }

            return me;
        },

        draw: function (easingValue) {
            var me = this;

            me.clear();

            if (helpers$1.isNullOrUndef(easingValue)) {
                easingValue = 1;
            }

            me.transition(easingValue);

            if (me.width <= 0 || me.height <= 0) {
                return;
            }

            if (core_plugins.notify(me, 'beforeDraw', [easingValue]) === false) {
                return;
            }

            // Draw all the scales
            helpers$1.each(me.boxes, function (box) {
                box.draw(me.chartArea);
            }, me);

            me.drawDatasets(easingValue);
            me._drawTooltip(easingValue);

            core_plugins.notify(me, 'afterDraw', [easingValue]);
        },

        /**
         * @private
         */
        transition: function (easingValue) {
            var me = this;

            for (var i = 0, ilen = (me.data.datasets || []).length; i < ilen; ++i) {
                if (me.isDatasetVisible(i)) {
                    me.getDatasetMeta(i).controller.transition(easingValue);
                }
            }

            me.tooltip.transition(easingValue);
        },

        /**
         * Draws all datasets unless a plugin returns `false` to the `beforeDatasetsDraw`
         * hook, in which case, plugins will not be called on `afterDatasetsDraw`.
         * @private
         */
        drawDatasets: function (easingValue) {
            var me = this;

            if (core_plugins.notify(me, 'beforeDatasetsDraw', [easingValue]) === false) {
                return;
            }

            // Draw datasets reversed to support proper line stacking
            for (var i = (me.data.datasets || []).length - 1; i >= 0; --i) {
                if (me.isDatasetVisible(i)) {
                    me.drawDataset(i, easingValue);
                }
            }

            core_plugins.notify(me, 'afterDatasetsDraw', [easingValue]);
        },

        /**
         * Draws dataset at index unless a plugin returns `false` to the `beforeDatasetDraw`
         * hook, in which case, plugins will not be called on `afterDatasetDraw`.
         * @private
         */
        drawDataset: function (index, easingValue) {
            var me = this;
            var meta = me.getDatasetMeta(index);
            var args = {
                meta: meta,
                index: index,
                easingValue: easingValue
            };

            if (core_plugins.notify(me, 'beforeDatasetDraw', [args]) === false) {
                return;
            }

            meta.controller.draw(easingValue);

            core_plugins.notify(me, 'afterDatasetDraw', [args]);
        },

        /**
         * Draws tooltip unless a plugin returns `false` to the `beforeTooltipDraw`
         * hook, in which case, plugins will not be called on `afterTooltipDraw`.
         * @private
         */
        _drawTooltip: function (easingValue) {
            var me = this;
            var tooltip = me.tooltip;
            var args = {
                tooltip: tooltip,
                easingValue: easingValue
            };

            if (core_plugins.notify(me, 'beforeTooltipDraw', [args]) === false) {
                return;
            }

            tooltip.draw();

            core_plugins.notify(me, 'afterTooltipDraw', [args]);
        },

        /**
         * Get the single element that was clicked on
         * @return An object containing the dataset index and element index of the matching element. Also contains the rectangle that was draw
         */
        getElementAtEvent: function (e) {
            return core_interaction.modes.single(this, e);
        },

        getElementsAtEvent: function (e) {
            return core_interaction.modes.label(this, e, { intersect: true });
        },

        getElementsAtXAxis: function (e) {
            return core_interaction.modes['x-axis'](this, e, { intersect: true });
        },

        getElementsAtEventForMode: function (e, mode, options) {
            var method = core_interaction.modes[mode];
            if (typeof method === 'function') {
                return method(this, e, options);
            }

            return [];
        },

        getDatasetAtEvent: function (e) {
            return core_interaction.modes.dataset(this, e, { intersect: true });
        },

        getDatasetMeta: function (datasetIndex) {
            var me = this;
            var dataset = me.data.datasets[datasetIndex];
            if (!dataset._meta) {
                dataset._meta = {};
            }

            var meta = dataset._meta[me.id];
            if (!meta) {
                meta = dataset._meta[me.id] = {
                    type: null,
                    data: [],
                    dataset: null,
                    controller: null,
                    hidden: null,			// See isDatasetVisible() comment
                    xAxisID: null,
                    yAxisID: null
                };
            }

            return meta;
        },

        getVisibleDatasetCount: function () {
            var count = 0;
            for (var i = 0, ilen = this.data.datasets.length; i < ilen; ++i) {
                if (this.isDatasetVisible(i)) {
                    count++;
                }
            }
            return count;
        },

        isDatasetVisible: function (datasetIndex) {
            var meta = this.getDatasetMeta(datasetIndex);

            // meta.hidden is a per chart dataset hidden flag override with 3 states: if true or false,
            // the dataset.hidden value is ignored, else if null, the dataset hidden state is returned.
            return typeof meta.hidden === 'boolean' ? !meta.hidden : !this.data.datasets[datasetIndex].hidden;
        },

        generateLegend: function () {
            return this.options.legendCallback(this);
        },

        /**
         * @private
         */
        destroyDatasetMeta: function (datasetIndex) {
            var id = this.id;
            var dataset = this.data.datasets[datasetIndex];
            var meta = dataset._meta && dataset._meta[id];

            if (meta) {
                meta.controller.destroy();
                delete dataset._meta[id];
            }
        },

        destroy: function () {
            var me = this;
            var canvas = me.canvas;
            var i, ilen;

            me.stop();

            // dataset controllers need to cleanup associated data
            for (i = 0, ilen = me.data.datasets.length; i < ilen; ++i) {
                me.destroyDatasetMeta(i);
            }

            if (canvas) {
                me.unbindEvents();
                helpers$1.canvas.clear(me);
                platform.releaseContext(me.ctx);
                me.canvas = null;
                me.ctx = null;
            }

            core_plugins.notify(me, 'destroy');

            delete Chart.instances[me.id];
        },

        toBase64Image: function () {
            return this.canvas.toDataURL.apply(this.canvas, arguments);
        },

        initToolTip: function () {
            var me = this;
            me.tooltip = new core_tooltip({
                _chart: me,
                _chartInstance: me, // deprecated, backward compatibility
                _data: me.data,
                _options: me.options.tooltips
            }, me);
        },

        /**
         * @private
         */
        bindEvents: function () {
            var me = this;
            var listeners = me._listeners = {};
            var listener = function () {
                me.eventHandler.apply(me, arguments);
            };

            helpers$1.each(me.options.events, function (type) {
                platform.addEventListener(me, type, listener);
                listeners[type] = listener;
            });

            // Elements used to detect size change should not be injected for non responsive charts.
            // See https://github.com/chartjs/Chart.js/issues/2210
            if (me.options.responsive) {
                listener = function () {
                    me.resize();
                };

                platform.addEventListener(me, 'resize', listener);
                listeners.resize = listener;
            }
        },

        /**
         * @private
         */
        unbindEvents: function () {
            var me = this;
            var listeners = me._listeners;
            if (!listeners) {
                return;
            }

            delete me._listeners;
            helpers$1.each(listeners, function (listener, type) {
                platform.removeEventListener(me, type, listener);
            });
        },

        updateHoverStyle: function (elements, mode, enabled) {
            var method = enabled ? 'setHoverStyle' : 'removeHoverStyle';
            var element, i, ilen;

            for (i = 0, ilen = elements.length; i < ilen; ++i) {
                element = elements[i];
                if (element) {
                    this.getDatasetMeta(element._datasetIndex).controller[method](element);
                }
            }
        },

        /**
         * @private
         */
        eventHandler: function (e) {
            var me = this;
            var tooltip = me.tooltip;

            if (core_plugins.notify(me, 'beforeEvent', [e]) === false) {
                return;
            }

            // Buffer any update calls so that renders do not occur
            me._bufferedRender = true;
            me._bufferedRequest = null;

            var changed = me.handleEvent(e);
            // for smooth tooltip animations issue #4989
            // the tooltip should be the source of change
            // Animation check workaround:
            // tooltip._start will be null when tooltip isn't animating
            if (tooltip) {
                changed = tooltip._start
                    ? tooltip.handleEvent(e)
                    : changed | tooltip.handleEvent(e);
            }

            core_plugins.notify(me, 'afterEvent', [e]);

            var bufferedRequest = me._bufferedRequest;
            if (bufferedRequest) {
                // If we have an update that was triggered, we need to do a normal render
                me.render(bufferedRequest);
            } else if (changed && !me.animating) {
                // If entering, leaving, or changing elements, animate the change via pivot
                me.stop();

                // We only need to render at this point. Updating will cause scales to be
                // recomputed generating flicker & using more memory than necessary.
                me.render({
                    duration: me.options.hover.animationDuration,
                    lazy: true
                });
            }

            me._bufferedRender = false;
            me._bufferedRequest = null;

            return me;
        },

        /**
         * Handle an event
         * @private
         * @param {IEvent} event the event to handle
         * @return {boolean} true if the chart needs to re-render
         */
        handleEvent: function (e) {
            var me = this;
            var options = me.options || {};
            var hoverOptions = options.hover;
            var changed = false;

            me.lastActive = me.lastActive || [];

            // Find Active Elements for hover and tooltips
            if (e.type === 'mouseout') {
                me.active = [];
            } else {
                me.active = me.getElementsAtEventForMode(e, hoverOptions.mode, hoverOptions);
            }

            // Invoke onHover hook
            // Need to call with native event here to not break backwards compatibility
            helpers$1.callback(options.onHover || options.hover.onHover, [e.native, me.active], me);

            if (e.type === 'mouseup' || e.type === 'click') {
                if (options.onClick) {
                    // Use e.native here for backwards compatibility
                    options.onClick.call(me, e.native, me.active);
                }
            }

            // Remove styling for last active (even if it may still be active)
            if (me.lastActive.length) {
                me.updateHoverStyle(me.lastActive, hoverOptions.mode, false);
            }

            // Built in hover styling
            if (me.active.length && hoverOptions.mode) {
                me.updateHoverStyle(me.active, hoverOptions.mode, true);
            }

            changed = !helpers$1.arrayEquals(me.active, me.lastActive);

            // Remember Last Actives
            me.lastActive = me.active;

            return changed;
        }
    });

    /**
     * NOTE(SB) We actually don't use this container anymore but we need to keep it
     * for backward compatibility. Though, it can still be useful for plugins that
     * would need to work on multiple charts?!
     */
    Chart.instances = {};

    var core_controller = Chart;

    // DEPRECATIONS

    /**
     * Provided for backward compatibility, use Chart instead.
     * @class Chart.Controller
     * @deprecated since version 2.6
     * @todo remove at version 3
     * @private
     */
    Chart.Controller = Chart;

    /**
     * Provided for backward compatibility, not available anymore.
     * @namespace Chart
     * @deprecated since version 2.8
     * @todo remove at version 3
     * @private
     */
    Chart.types = {};

    /**
     * Provided for backward compatibility, not available anymore.
     * @namespace Chart.helpers.configMerge
     * @deprecated since version 2.8.0
     * @todo remove at version 3
     * @private
     */
    helpers$1.configMerge = mergeConfig;

    /**
     * Provided for backward compatibility, not available anymore.
     * @namespace Chart.helpers.scaleMerge
     * @deprecated since version 2.8.0
     * @todo remove at version 3
     * @private
     */
    helpers$1.scaleMerge = mergeScaleConfig;

    var core_helpers = function () {

        // -- Basic js utility methods

        helpers$1.where = function (collection, filterCallback) {
            if (helpers$1.isArray(collection) && Array.prototype.filter) {
                return collection.filter(filterCallback);
            }
            var filtered = [];

            helpers$1.each(collection, function (item) {
                if (filterCallback(item)) {
                    filtered.push(item);
                }
            });

            return filtered;
        };
        helpers$1.findIndex = Array.prototype.findIndex ?
            function (array, callback, scope) {
                return array.findIndex(callback, scope);
            } :
            function (array, callback, scope) {
                scope = scope === undefined ? array : scope;
                for (var i = 0, ilen = array.length; i < ilen; ++i) {
                    if (callback.call(scope, array[i], i, array)) {
                        return i;
                    }
                }
                return -1;
            };
        helpers$1.findNextWhere = function (arrayToSearch, filterCallback, startIndex) {
            // Default to start of the array
            if (helpers$1.isNullOrUndef(startIndex)) {
                startIndex = -1;
            }
            for (var i = startIndex + 1; i < arrayToSearch.length; i++) {
                var currentItem = arrayToSearch[i];
                if (filterCallback(currentItem)) {
                    return currentItem;
                }
            }
        };
        helpers$1.findPreviousWhere = function (arrayToSearch, filterCallback, startIndex) {
            // Default to end of the array
            if (helpers$1.isNullOrUndef(startIndex)) {
                startIndex = arrayToSearch.length;
            }
            for (var i = startIndex - 1; i >= 0; i--) {
                var currentItem = arrayToSearch[i];
                if (filterCallback(currentItem)) {
                    return currentItem;
                }
            }
        };

        // -- Math methods
        helpers$1.isNumber = function (n) {
            return !isNaN(parseFloat(n)) && isFinite(n);
        };
        helpers$1.almostEquals = function (x, y, epsilon) {
            return Math.abs(x - y) < epsilon;
        };
        helpers$1.almostWhole = function (x, epsilon) {
            var rounded = Math.round(x);
            return (((rounded - epsilon) < x) && ((rounded + epsilon) > x));
        };
        helpers$1.max = function (array) {
            return array.reduce(function (max, value) {
                if (!isNaN(value)) {
                    return Math.max(max, value);
                }
                return max;
            }, Number.NEGATIVE_INFINITY);
        };
        helpers$1.min = function (array) {
            return array.reduce(function (min, value) {
                if (!isNaN(value)) {
                    return Math.min(min, value);
                }
                return min;
            }, Number.POSITIVE_INFINITY);
        };
        helpers$1.sign = Math.sign ?
            function (x) {
                return Math.sign(x);
            } :
            function (x) {
                x = +x; // convert to a number
                if (x === 0 || isNaN(x)) {
                    return x;
                }
                return x > 0 ? 1 : -1;
            };
        helpers$1.log10 = Math.log10 ?
            function (x) {
                return Math.log10(x);
            } :
            function (x) {
                var exponent = Math.log(x) * Math.LOG10E; // Math.LOG10E = 1 / Math.LN10.
                // Check for whole powers of 10,
                // which due to floating point rounding error should be corrected.
                var powerOf10 = Math.round(exponent);
                var isPowerOf10 = x === Math.pow(10, powerOf10);

                return isPowerOf10 ? powerOf10 : exponent;
            };
        helpers$1.toRadians = function (degrees) {
            return degrees * (Math.PI / 180);
        };
        helpers$1.toDegrees = function (radians) {
            return radians * (180 / Math.PI);
        };

        /**
         * Returns the number of decimal places
         * i.e. the number of digits after the decimal point, of the value of this Number.
         * @param {number} x - A number.
         * @returns {number} The number of decimal places.
         * @private
         */
        helpers$1._decimalPlaces = function (x) {
            if (!helpers$1.isFinite(x)) {
                return;
            }
            var e = 1;
            var p = 0;
            while (Math.round(x * e) / e !== x) {
                e *= 10;
                p++;
            }
            return p;
        };

        // Gets the angle from vertical upright to the point about a centre.
        helpers$1.getAngleFromPoint = function (centrePoint, anglePoint) {
            var distanceFromXCenter = anglePoint.x - centrePoint.x;
            var distanceFromYCenter = anglePoint.y - centrePoint.y;
            var radialDistanceFromCenter = Math.sqrt(distanceFromXCenter * distanceFromXCenter + distanceFromYCenter * distanceFromYCenter);

            var angle = Math.atan2(distanceFromYCenter, distanceFromXCenter);

            if (angle < (-0.5 * Math.PI)) {
                angle += 2.0 * Math.PI; // make sure the returned angle is in the range of (-PI/2, 3PI/2]
            }

            return {
                angle: angle,
                distance: radialDistanceFromCenter
            };
        };
        helpers$1.distanceBetweenPoints = function (pt1, pt2) {
            return Math.sqrt(Math.pow(pt2.x - pt1.x, 2) + Math.pow(pt2.y - pt1.y, 2));
        };

        /**
         * Provided for backward compatibility, not available anymore
         * @function Chart.helpers.aliasPixel
         * @deprecated since version 2.8.0
         * @todo remove at version 3
         */
        helpers$1.aliasPixel = function (pixelWidth) {
            return (pixelWidth % 2 === 0) ? 0 : 0.5;
        };

        /**
         * Returns the aligned pixel value to avoid anti-aliasing blur
         * @param {Chart} chart - The chart instance.
         * @param {number} pixel - A pixel value.
         * @param {number} width - The width of the element.
         * @returns {number} The aligned pixel value.
         * @private
         */
        helpers$1._alignPixel = function (chart, pixel, width) {
            var devicePixelRatio = chart.currentDevicePixelRatio;
            var halfWidth = width / 2;
            return Math.round((pixel - halfWidth) * devicePixelRatio) / devicePixelRatio + halfWidth;
        };

        helpers$1.splineCurve = function (firstPoint, middlePoint, afterPoint, t) {
            // Props to Rob Spencer at scaled innovation for his post on splining between points
            // http://scaledinnovation.com/analytics/splines/aboutSplines.html

            // This function must also respect "skipped" points

            var previous = firstPoint.skip ? middlePoint : firstPoint;
            var current = middlePoint;
            var next = afterPoint.skip ? middlePoint : afterPoint;

            var d01 = Math.sqrt(Math.pow(current.x - previous.x, 2) + Math.pow(current.y - previous.y, 2));
            var d12 = Math.sqrt(Math.pow(next.x - current.x, 2) + Math.pow(next.y - current.y, 2));

            var s01 = d01 / (d01 + d12);
            var s12 = d12 / (d01 + d12);

            // If all points are the same, s01 & s02 will be inf
            s01 = isNaN(s01) ? 0 : s01;
            s12 = isNaN(s12) ? 0 : s12;

            var fa = t * s01; // scaling factor for triangle Ta
            var fb = t * s12;

            return {
                previous: {
                    x: current.x - fa * (next.x - previous.x),
                    y: current.y - fa * (next.y - previous.y)
                },
                next: {
                    x: current.x + fb * (next.x - previous.x),
                    y: current.y + fb * (next.y - previous.y)
                }
            };
        };
        helpers$1.EPSILON = Number.EPSILON || 1e-14;
        helpers$1.splineCurveMonotone = function (points) {
            // This function calculates BÃ©zier control points in a similar way than |splineCurve|,
            // but preserves monotonicity of the provided data and ensures no local extremums are added
            // between the dataset discrete points due to the interpolation.
            // See : https://en.wikipedia.org/wiki/Monotone_cubic_interpolation

            var pointsWithTangents = (points || []).map(function (point) {
                return {
                    model: point._model,
                    deltaK: 0,
                    mK: 0
                };
            });

            // Calculate slopes (deltaK) and initialize tangents (mK)
            var pointsLen = pointsWithTangents.length;
            var i, pointBefore, pointCurrent, pointAfter;
            for (i = 0; i < pointsLen; ++i) {
                pointCurrent = pointsWithTangents[i];
                if (pointCurrent.model.skip) {
                    continue;
                }

                pointBefore = i > 0 ? pointsWithTangents[i - 1] : null;
                pointAfter = i < pointsLen - 1 ? pointsWithTangents[i + 1] : null;
                if (pointAfter && !pointAfter.model.skip) {
                    var slopeDeltaX = (pointAfter.model.x - pointCurrent.model.x);

                    // In the case of two points that appear at the same x pixel, slopeDeltaX is 0
                    pointCurrent.deltaK = slopeDeltaX !== 0 ? (pointAfter.model.y - pointCurrent.model.y) / slopeDeltaX : 0;
                }

                if (!pointBefore || pointBefore.model.skip) {
                    pointCurrent.mK = pointCurrent.deltaK;
                } else if (!pointAfter || pointAfter.model.skip) {
                    pointCurrent.mK = pointBefore.deltaK;
                } else if (this.sign(pointBefore.deltaK) !== this.sign(pointCurrent.deltaK)) {
                    pointCurrent.mK = 0;
                } else {
                    pointCurrent.mK = (pointBefore.deltaK + pointCurrent.deltaK) / 2;
                }
            }

            // Adjust tangents to ensure monotonic properties
            var alphaK, betaK, tauK, squaredMagnitude;
            for (i = 0; i < pointsLen - 1; ++i) {
                pointCurrent = pointsWithTangents[i];
                pointAfter = pointsWithTangents[i + 1];
                if (pointCurrent.model.skip || pointAfter.model.skip) {
                    continue;
                }

                if (helpers$1.almostEquals(pointCurrent.deltaK, 0, this.EPSILON)) {
                    pointCurrent.mK = pointAfter.mK = 0;
                    continue;
                }

                alphaK = pointCurrent.mK / pointCurrent.deltaK;
                betaK = pointAfter.mK / pointCurrent.deltaK;
                squaredMagnitude = Math.pow(alphaK, 2) + Math.pow(betaK, 2);
                if (squaredMagnitude <= 9) {
                    continue;
                }

                tauK = 3 / Math.sqrt(squaredMagnitude);
                pointCurrent.mK = alphaK * tauK * pointCurrent.deltaK;
                pointAfter.mK = betaK * tauK * pointCurrent.deltaK;
            }

            // Compute control points
            var deltaX;
            for (i = 0; i < pointsLen; ++i) {
                pointCurrent = pointsWithTangents[i];
                if (pointCurrent.model.skip) {
                    continue;
                }

                pointBefore = i > 0 ? pointsWithTangents[i - 1] : null;
                pointAfter = i < pointsLen - 1 ? pointsWithTangents[i + 1] : null;
                if (pointBefore && !pointBefore.model.skip) {
                    deltaX = (pointCurrent.model.x - pointBefore.model.x) / 3;
                    pointCurrent.model.controlPointPreviousX = pointCurrent.model.x - deltaX;
                    pointCurrent.model.controlPointPreviousY = pointCurrent.model.y - deltaX * pointCurrent.mK;
                }
                if (pointAfter && !pointAfter.model.skip) {
                    deltaX = (pointAfter.model.x - pointCurrent.model.x) / 3;
                    pointCurrent.model.controlPointNextX = pointCurrent.model.x + deltaX;
                    pointCurrent.model.controlPointNextY = pointCurrent.model.y + deltaX * pointCurrent.mK;
                }
            }
        };
        helpers$1.nextItem = function (collection, index, loop) {
            if (loop) {
                return index >= collection.length - 1 ? collection[0] : collection[index + 1];
            }
            return index >= collection.length - 1 ? collection[collection.length - 1] : collection[index + 1];
        };
        helpers$1.previousItem = function (collection, index, loop) {
            if (loop) {
                return index <= 0 ? collection[collection.length - 1] : collection[index - 1];
            }
            return index <= 0 ? collection[0] : collection[index - 1];
        };
        // Implementation of the nice number algorithm used in determining where axis labels will go
        helpers$1.niceNum = function (range, round) {
            var exponent = Math.floor(helpers$1.log10(range));
            var fraction = range / Math.pow(10, exponent);
            var niceFraction;

            if (round) {
                if (fraction < 1.5) {
                    niceFraction = 1;
                } else if (fraction < 3) {
                    niceFraction = 2;
                } else if (fraction < 7) {
                    niceFraction = 5;
                } else {
                    niceFraction = 10;
                }
            } else if (fraction <= 1.0) {
                niceFraction = 1;
            } else if (fraction <= 2) {
                niceFraction = 2;
            } else if (fraction <= 5) {
                niceFraction = 5;
            } else {
                niceFraction = 10;
            }

            return niceFraction * Math.pow(10, exponent);
        };
        // Request animation polyfill - https://www.paulirish.com/2011/requestanimationframe-for-smart-animating/
        helpers$1.requestAnimFrame = (function () {
            if (typeof window === 'undefined') {
                return function (callback) {
                    callback();
                };
            }
            return window.requestAnimationFrame ||
                window.webkitRequestAnimationFrame ||
                window.mozRequestAnimationFrame ||
                window.oRequestAnimationFrame ||
                window.msRequestAnimationFrame ||
                function (callback) {
                    return window.setTimeout(callback, 1000 / 60);
                };
        }());
        // -- DOM methods
        helpers$1.getRelativePosition = function (evt, chart) {
            var mouseX, mouseY;
            var e = evt.originalEvent || evt;
            var canvas = evt.target || evt.srcElement;
            var boundingRect = canvas.getBoundingClientRect();

            var touches = e.touches;
            if (touches && touches.length > 0) {
                mouseX = touches[0].clientX;
                mouseY = touches[0].clientY;

            } else {
                mouseX = e.clientX;
                mouseY = e.clientY;
            }

            // Scale mouse coordinates into canvas coordinates
            // by following the pattern laid out by 'jerryj' in the comments of
            // https://www.html5canvastutorials.com/advanced/html5-canvas-mouse-coordinates/
            var paddingLeft = parseFloat(helpers$1.getStyle(canvas, 'padding-left'));
            var paddingTop = parseFloat(helpers$1.getStyle(canvas, 'padding-top'));
            var paddingRight = parseFloat(helpers$1.getStyle(canvas, 'padding-right'));
            var paddingBottom = parseFloat(helpers$1.getStyle(canvas, 'padding-bottom'));
            var width = boundingRect.right - boundingRect.left - paddingLeft - paddingRight;
            var height = boundingRect.bottom - boundingRect.top - paddingTop - paddingBottom;

            // We divide by the current device pixel ratio, because the canvas is scaled up by that amount in each direction. However
            // the backend model is in unscaled coordinates. Since we are going to deal with our model coordinates, we go back here
            mouseX = Math.round((mouseX - boundingRect.left - paddingLeft) / (width) * canvas.width / chart.currentDevicePixelRatio);
            mouseY = Math.round((mouseY - boundingRect.top - paddingTop) / (height) * canvas.height / chart.currentDevicePixelRatio);

            return {
                x: mouseX,
                y: mouseY
            };

        };

        // Private helper function to convert max-width/max-height values that may be percentages into a number
        function parseMaxStyle(styleValue, node, parentProperty) {
            var valueInPixels;
            if (typeof styleValue === 'string') {
                valueInPixels = parseInt(styleValue, 10);

                if (styleValue.indexOf('%') !== -1) {
                    // percentage * size in dimension
                    valueInPixels = valueInPixels / 100 * node.parentNode[parentProperty];
                }
            } else {
                valueInPixels = styleValue;
            }

            return valueInPixels;
        }

        /**
         * Returns if the given value contains an effective constraint.
         * @private
         */
        function isConstrainedValue(value) {
            return value !== undefined && value !== null && value !== 'none';
        }

        /**
         * Returns the max width or height of the given DOM node in a cross-browser compatible fashion
         * @param {HTMLElement} domNode - the node to check the constraint on
         * @param {string} maxStyle - the style that defines the maximum for the direction we are using ('max-width' / 'max-height')
         * @param {string} percentageProperty - property of parent to use when calculating width as a percentage
         * @see {@link https://www.nathanaeljones.com/blog/2013/reading-max-width-cross-browser}
         */
        function getConstraintDimension(domNode, maxStyle, percentageProperty) {
            var view = document.defaultView;
            var parentNode = helpers$1._getParentNode(domNode);
            var constrainedNode = view.getComputedStyle(domNode)[maxStyle];
            var constrainedContainer = view.getComputedStyle(parentNode)[maxStyle];
            var hasCNode = isConstrainedValue(constrainedNode);
            var hasCContainer = isConstrainedValue(constrainedContainer);
            var infinity = Number.POSITIVE_INFINITY;

            if (hasCNode || hasCContainer) {
                return Math.min(
                    hasCNode ? parseMaxStyle(constrainedNode, domNode, percentageProperty) : infinity,
                    hasCContainer ? parseMaxStyle(constrainedContainer, parentNode, percentageProperty) : infinity);
            }

            return 'none';
        }
        // returns Number or undefined if no constraint
        helpers$1.getConstraintWidth = function (domNode) {
            return getConstraintDimension(domNode, 'max-width', 'clientWidth');
        };
        // returns Number or undefined if no constraint
        helpers$1.getConstraintHeight = function (domNode) {
            return getConstraintDimension(domNode, 'max-height', 'clientHeight');
        };
        /**
         * @private
           */
        helpers$1._calculatePadding = function (container, padding, parentDimension) {
            padding = helpers$1.getStyle(container, padding);

            return padding.indexOf('%') > -1 ? parentDimension * parseInt(padding, 10) / 100 : parseInt(padding, 10);
        };
        /**
         * @private
         */
        helpers$1._getParentNode = function (domNode) {
            var parent = domNode.parentNode;
            if (parent && parent.toString() === '[object ShadowRoot]') {
                parent = parent.host;
            }
            return parent;
        };
        helpers$1.getMaximumWidth = function (domNode) {
            var container = helpers$1._getParentNode(domNode);
            if (!container) {
                return domNode.clientWidth;
            }

            var clientWidth = container.clientWidth;
            var paddingLeft = helpers$1._calculatePadding(container, 'padding-left', clientWidth);
            var paddingRight = helpers$1._calculatePadding(container, 'padding-right', clientWidth);

            var w = clientWidth - paddingLeft - paddingRight;
            var cw = helpers$1.getConstraintWidth(domNode);
            return isNaN(cw) ? w : Math.min(w, cw);
        };
        helpers$1.getMaximumHeight = function (domNode) {
            var container = helpers$1._getParentNode(domNode);
            if (!container) {
                return domNode.clientHeight;
            }

            var clientHeight = container.clientHeight;
            var paddingTop = helpers$1._calculatePadding(container, 'padding-top', clientHeight);
            var paddingBottom = helpers$1._calculatePadding(container, 'padding-bottom', clientHeight);

            var h = clientHeight - paddingTop - paddingBottom;
            var ch = helpers$1.getConstraintHeight(domNode);
            return isNaN(ch) ? h : Math.min(h, ch);
        };
        helpers$1.getStyle = function (el, property) {
            return el.currentStyle ?
                el.currentStyle[property] :
                document.defaultView.getComputedStyle(el, null).getPropertyValue(property);
        };
        helpers$1.retinaScale = function (chart, forceRatio) {
            var pixelRatio = chart.currentDevicePixelRatio = forceRatio || (typeof window !== 'undefined' && window.devicePixelRatio) || 1;
            if (pixelRatio === 1) {
                return;
            }

            var canvas = chart.canvas;
            var height = chart.height;
            var width = chart.width;

            canvas.height = height * pixelRatio;
            canvas.width = width * pixelRatio;
            chart.ctx.scale(pixelRatio, pixelRatio);

            // If no style has been set on the canvas, the render size is used as display size,
            // making the chart visually bigger, so let's enforce it to the "correct" values.
            // See https://github.com/chartjs/Chart.js/issues/3575
            if (!canvas.style.height && !canvas.style.width) {
                canvas.style.height = height + 'px';
                canvas.style.width = width + 'px';
            }
        };
        // -- Canvas methods
        helpers$1.fontString = function (pixelSize, fontStyle, fontFamily) {
            return fontStyle + ' ' + pixelSize + 'px ' + fontFamily;
        };
        helpers$1.longestText = function (ctx, font, arrayOfThings, cache) {
            cache = cache || {};
            var data = cache.data = cache.data || {};
            var gc = cache.garbageCollect = cache.garbageCollect || [];

            if (cache.font !== font) {
                data = cache.data = {};
                gc = cache.garbageCollect = [];
                cache.font = font;
            }

            ctx.font = font;
            var longest = 0;
            helpers$1.each(arrayOfThings, function (thing) {
                // Undefined strings and arrays should not be measured
                if (thing !== undefined && thing !== null && helpers$1.isArray(thing) !== true) {
                    longest = helpers$1.measureText(ctx, data, gc, longest, thing);
                } else if (helpers$1.isArray(thing)) {
                    // if it is an array lets measure each element
                    // to do maybe simplify this function a bit so we can do this more recursively?
                    helpers$1.each(thing, function (nestedThing) {
                        // Undefined strings and arrays should not be measured
                        if (nestedThing !== undefined && nestedThing !== null && !helpers$1.isArray(nestedThing)) {
                            longest = helpers$1.measureText(ctx, data, gc, longest, nestedThing);
                        }
                    });
                }
            });

            var gcLen = gc.length / 2;
            if (gcLen > arrayOfThings.length) {
                for (var i = 0; i < gcLen; i++) {
                    delete data[gc[i]];
                }
                gc.splice(0, gcLen);
            }
            return longest;
        };
        helpers$1.measureText = function (ctx, data, gc, longest, string) {
            var textWidth = data[string];
            if (!textWidth) {
                textWidth = data[string] = ctx.measureText(string).width;
                gc.push(string);
            }
            if (textWidth > longest) {
                longest = textWidth;
            }
            return longest;
        };
        helpers$1.numberOfLabelLines = function (arrayOfThings) {
            var numberOfLines = 1;
            helpers$1.each(arrayOfThings, function (thing) {
                if (helpers$1.isArray(thing)) {
                    if (thing.length > numberOfLines) {
                        numberOfLines = thing.length;
                    }
                }
            });
            return numberOfLines;
        };

        helpers$1.color = !chartjsColor ?
            function (value) {
                console.error('Color.js not found!');
                return value;
            } :
            function (value) {
                /* global CanvasGradient */
                if (value instanceof CanvasGradient) {
                    value = core_defaults.global.defaultColor;
                }

                return chartjsColor(value);
            };

        helpers$1.getHoverColor = function (colorValue) {
            /* global CanvasPattern */
            return (colorValue instanceof CanvasPattern || colorValue instanceof CanvasGradient) ?
                colorValue :
                helpers$1.color(colorValue).saturate(0.5).darken(0.1).rgbString();
        };
    };

    function abstract() {
        throw new Error(
            'This method is not implemented: either no adapter can ' +
            'be found or an incomplete integration was provided.'
        );
    }

    /**
     * Date adapter (current used by the time scale)
     * @namespace Chart._adapters._date
     * @memberof Chart._adapters
     * @private
     */

    /**
     * Currently supported unit string values.
     * @typedef {('millisecond'|'second'|'minute'|'hour'|'day'|'week'|'month'|'quarter'|'year')}
     * @memberof Chart._adapters._date
     * @name Unit
     */

    /**
     * @class
     */
    function DateAdapter(options) {
        this.options = options || {};
    }

    helpers$1.extend(DateAdapter.prototype, /** @lends DateAdapter */ {
        /**
         * Returns a map of time formats for the supported formatting units defined
         * in Unit as well as 'datetime' representing a detailed date/time string.
         * @returns {{string: string}}
         */
        formats: abstract,

        /**
         * Parses the given `value` and return the associated timestamp.
         * @param {any} value - the value to parse (usually comes from the data)
         * @param {string} [format] - the expected data format
         * @returns {(number|null)}
         * @function
         */
        parse: abstract,

        /**
         * Returns the formatted date in the specified `format` for a given `timestamp`.
         * @param {number} timestamp - the timestamp to format
         * @param {string} format - the date/time token
         * @return {string}
         * @function
         */
        format: abstract,

        /**
         * Adds the specified `amount` of `unit` to the given `timestamp`.
         * @param {number} timestamp - the input timestamp
         * @param {number} amount - the amount to add
         * @param {Unit} unit - the unit as string
         * @return {number}
         * @function
         */
        add: abstract,

        /**
         * Returns the number of `unit` between the given timestamps.
         * @param {number} max - the input timestamp (reference)
         * @param {number} min - the timestamp to substract
         * @param {Unit} unit - the unit as string
         * @return {number}
         * @function
         */
        diff: abstract,

        /**
         * Returns start of `unit` for the given `timestamp`.
         * @param {number} timestamp - the input timestamp
         * @param {Unit} unit - the unit as string
         * @param {number} [weekday] - the ISO day of the week with 1 being Monday
         * and 7 being Sunday (only needed if param *unit* is `isoWeek`).
         * @function
         */
        startOf: abstract,

        /**
         * Returns end of `unit` for the given `timestamp`.
         * @param {number} timestamp - the input timestamp
         * @param {Unit} unit - the unit as string
         * @function
         */
        endOf: abstract,

        // DEPRECATIONS

        /**
         * Provided for backward compatibility for scale.getValueForPixel(),
         * this method should be overridden only by the moment adapter.
         * @deprecated since version 2.8.0
         * @todo remove at version 3
         * @private
         */
        _create: function (value) {
            return value;
        }
    });

    DateAdapter.override = function (members) {
        helpers$1.extend(DateAdapter.prototype, members);
    };

    var _date = DateAdapter;

    var core_adapters = {
        _date: _date
    };

    /**
     * Namespace to hold static tick generation functions
     * @namespace Chart.Ticks
     */
    var core_ticks = {
        /**
         * Namespace to hold formatters for different types of ticks
         * @namespace Chart.Ticks.formatters
         */
        formatters: {
            /**
             * Formatter for value labels
             * @method Chart.Ticks.formatters.values
             * @param value the value to display
             * @return {string|string[]} the label to display
             */
            values: function (value) {
                return helpers$1.isArray(value) ? value : '' + value;
            },

            /**
             * Formatter for linear numeric ticks
             * @method Chart.Ticks.formatters.linear
             * @param tickValue {number} the value to be formatted
             * @param index {number} the position of the tickValue parameter in the ticks array
             * @param ticks {number[]} the list of ticks being converted
             * @return {string} string representation of the tickValue parameter
             */
            linear: function (tickValue, index, ticks) {
                // If we have lots of ticks, don't use the ones
                var delta = ticks.length > 3 ? ticks[2] - ticks[1] : ticks[1] - ticks[0];

                // If we have a number like 2.5 as the delta, figure out how many decimal places we need
                if (Math.abs(delta) > 1) {
                    if (tickValue !== Math.floor(tickValue)) {
                        // not an integer
                        delta = tickValue - Math.floor(tickValue);
                    }
                }

                var logDelta = helpers$1.log10(Math.abs(delta));
                var tickString = '';

                if (tickValue !== 0) {
                    var maxTick = Math.max(Math.abs(ticks[0]), Math.abs(ticks[ticks.length - 1]));
                    if (maxTick < 1e-4) { // all ticks are small numbers; use scientific notation
                        var logTick = helpers$1.log10(Math.abs(tickValue));
                        tickString = tickValue.toExponential(Math.floor(logTick) - Math.floor(logDelta));
                    } else {
                        var numDecimal = -1 * Math.floor(logDelta);
                        numDecimal = Math.max(Math.min(numDecimal, 20), 0); // toFixed has a max of 20 decimal places
                        tickString = tickValue.toFixed(numDecimal);
                    }
                } else {
                    tickString = '0'; // never show decimal places for 0
                }

                return tickString;
            },

            logarithmic: function (tickValue, index, ticks) {
                var remain = tickValue / (Math.pow(10, Math.floor(helpers$1.log10(tickValue))));

                if (tickValue === 0) {
                    return '0';
                } else if (remain === 1 || remain === 2 || remain === 5 || index === 0 || index === ticks.length - 1) {
                    return tickValue.toExponential();
                }
                return '';
            }
        }
    };

    var valueOrDefault$9 = helpers$1.valueOrDefault;
    var valueAtIndexOrDefault = helpers$1.valueAtIndexOrDefault;

    core_defaults._set('scale', {
        display: true,
        position: 'left',
        offset: false,

        // grid line settings
        gridLines: {
            display: true,
            color: 'rgba(0, 0, 0, 0.1)',
            lineWidth: 1,
            drawBorder: true,
            drawOnChartArea: true,
            drawTicks: true,
            tickMarkLength: 10,
            zeroLineWidth: 1,
            zeroLineColor: 'rgba(0,0,0,0.25)',
            zeroLineBorderDash: [],
            zeroLineBorderDashOffset: 0.0,
            offsetGridLines: false,
            borderDash: [],
            borderDashOffset: 0.0
        },

        // scale label
        scaleLabel: {
            // display property
            display: false,

            // actual label
            labelString: '',

            // top/bottom padding
            padding: {
                top: 4,
                bottom: 4
            }
        },

        // label settings
        ticks: {
            beginAtZero: false,
            minRotation: 0,
            maxRotation: 50,
            mirror: false,
            padding: 0,
            reverse: false,
            display: true,
            autoSkip: true,
            autoSkipPadding: 0,
            labelOffset: 0,
            // We pass through arrays to be rendered as multiline labels, we convert Others to strings here.
            callback: core_ticks.formatters.values,
            minor: {},
            major: {}
        }
    });

    function labelsFromTicks(ticks) {
        var labels = [];
        var i, ilen;

        for (i = 0, ilen = ticks.length; i < ilen; ++i) {
            labels.push(ticks[i].label);
        }

        return labels;
    }

    function getPixelForGridLine(scale, index, offsetGridLines) {
        var lineValue = scale.getPixelForTick(index);

        if (offsetGridLines) {
            if (scale.getTicks().length === 1) {
                lineValue -= scale.isHorizontal() ?
                    Math.max(lineValue - scale.left, scale.right - lineValue) :
                    Math.max(lineValue - scale.top, scale.bottom - lineValue);
            } else if (index === 0) {
                lineValue -= (scale.getPixelForTick(1) - lineValue) / 2;
            } else {
                lineValue -= (lineValue - scale.getPixelForTick(index - 1)) / 2;
            }
        }
        return lineValue;
    }

    function computeTextSize(context, tick, font) {
        return helpers$1.isArray(tick) ?
            helpers$1.longestText(context, font, tick) :
            context.measureText(tick).width;
    }

    var core_scale = core_element.extend({
        /**
         * Get the padding needed for the scale
         * @method getPadding
         * @private
         * @returns {Padding} the necessary padding
         */
        getPadding: function () {
            var me = this;
            return {
                left: me.paddingLeft || 0,
                top: me.paddingTop || 0,
                right: me.paddingRight || 0,
                bottom: me.paddingBottom || 0
            };
        },

        /**
         * Returns the scale tick objects ({label, major})
         * @since 2.7
         */
        getTicks: function () {
            return this._ticks;
        },

        // These methods are ordered by lifecyle. Utilities then follow.
        // Any function defined here is inherited by all scale types.
        // Any function can be extended by the scale type

        mergeTicksOptions: function () {
            var ticks = this.options.ticks;
            if (ticks.minor === false) {
                ticks.minor = {
                    display: false
                };
            }
            if (ticks.major === false) {
                ticks.major = {
                    display: false
                };
            }
            for (var key in ticks) {
                if (key !== 'major' && key !== 'minor') {
                    if (typeof ticks.minor[key] === 'undefined') {
                        ticks.minor[key] = ticks[key];
                    }
                    if (typeof ticks.major[key] === 'undefined') {
                        ticks.major[key] = ticks[key];
                    }
                }
            }
        },
        beforeUpdate: function () {
            helpers$1.callback(this.options.beforeUpdate, [this]);
        },

        update: function (maxWidth, maxHeight, margins) {
            var me = this;
            var i, ilen, labels, label, ticks, tick;

            // Update Lifecycle - Probably don't want to ever extend or overwrite this function ;)
            me.beforeUpdate();

            // Absorb the master measurements
            me.maxWidth = maxWidth;
            me.maxHeight = maxHeight;
            me.margins = helpers$1.extend({
                left: 0,
                right: 0,
                top: 0,
                bottom: 0
            }, margins);

            me._maxLabelLines = 0;
            me.longestLabelWidth = 0;
            me.longestTextCache = me.longestTextCache || {};

            // Dimensions
            me.beforeSetDimensions();
            me.setDimensions();
            me.afterSetDimensions();

            // Data min/max
            me.beforeDataLimits();
            me.determineDataLimits();
            me.afterDataLimits();

            // Ticks - `this.ticks` is now DEPRECATED!
            // Internal ticks are now stored as objects in the PRIVATE `this._ticks` member
            // and must not be accessed directly from outside this class. `this.ticks` being
            // around for long time and not marked as private, we can't change its structure
            // without unexpected breaking changes. If you need to access the scale ticks,
            // use scale.getTicks() instead.

            me.beforeBuildTicks();

            // New implementations should return an array of objects but for BACKWARD COMPAT,
            // we still support no return (`this.ticks` internally set by calling this method).
            ticks = me.buildTicks() || [];

            // Allow modification of ticks in callback.
            ticks = me.afterBuildTicks(ticks) || ticks;

            me.beforeTickToLabelConversion();

            // New implementations should return the formatted tick labels but for BACKWARD
            // COMPAT, we still support no return (`this.ticks` internally changed by calling
            // this method and supposed to contain only string values).
            labels = me.convertTicksToLabels(ticks) || me.ticks;

            me.afterTickToLabelConversion();

            me.ticks = labels;   // BACKWARD COMPATIBILITY

            // IMPORTANT: from this point, we consider that `this.ticks` will NEVER change!

            // BACKWARD COMPAT: synchronize `_ticks` with labels (so potentially `this.ticks`)
            for (i = 0, ilen = labels.length; i < ilen; ++i) {
                label = labels[i];
                tick = ticks[i];
                if (!tick) {
                    ticks.push(tick = {
                        label: label,
                        major: false
                    });
                } else {
                    tick.label = label;
                }
            }

            me._ticks = ticks;

            // Tick Rotation
            me.beforeCalculateTickRotation();
            me.calculateTickRotation();
            me.afterCalculateTickRotation();
            // Fit
            me.beforeFit();
            me.fit();
            me.afterFit();
            //
            me.afterUpdate();

            return me.minSize;

        },
        afterUpdate: function () {
            helpers$1.callback(this.options.afterUpdate, [this]);
        },

        //

        beforeSetDimensions: function () {
            helpers$1.callback(this.options.beforeSetDimensions, [this]);
        },
        setDimensions: function () {
            var me = this;
            // Set the unconstrained dimension before label rotation
            if (me.isHorizontal()) {
                // Reset position before calculating rotation
                me.width = me.maxWidth;
                me.left = 0;
                me.right = me.width;
            } else {
                me.height = me.maxHeight;

                // Reset position before calculating rotation
                me.top = 0;
                me.bottom = me.height;
            }

            // Reset padding
            me.paddingLeft = 0;
            me.paddingTop = 0;
            me.paddingRight = 0;
            me.paddingBottom = 0;
        },
        afterSetDimensions: function () {
            helpers$1.callback(this.options.afterSetDimensions, [this]);
        },

        // Data limits
        beforeDataLimits: function () {
            helpers$1.callback(this.options.beforeDataLimits, [this]);
        },
        determineDataLimits: helpers$1.noop,
        afterDataLimits: function () {
            helpers$1.callback(this.options.afterDataLimits, [this]);
        },

        //
        beforeBuildTicks: function () {
            helpers$1.callback(this.options.beforeBuildTicks, [this]);
        },
        buildTicks: helpers$1.noop,
        afterBuildTicks: function (ticks) {
            var me = this;
            // ticks is empty for old axis implementations here
            if (helpers$1.isArray(ticks) && ticks.length) {
                return helpers$1.callback(me.options.afterBuildTicks, [me, ticks]);
            }
            // Support old implementations (that modified `this.ticks` directly in buildTicks)
            me.ticks = helpers$1.callback(me.options.afterBuildTicks, [me, me.ticks]) || me.ticks;
            return ticks;
        },

        beforeTickToLabelConversion: function () {
            helpers$1.callback(this.options.beforeTickToLabelConversion, [this]);
        },
        convertTicksToLabels: function () {
            var me = this;
            // Convert ticks to strings
            var tickOpts = me.options.ticks;
            me.ticks = me.ticks.map(tickOpts.userCallback || tickOpts.callback, this);
        },
        afterTickToLabelConversion: function () {
            helpers$1.callback(this.options.afterTickToLabelConversion, [this]);
        },

        //

        beforeCalculateTickRotation: function () {
            helpers$1.callback(this.options.beforeCalculateTickRotation, [this]);
        },
        calculateTickRotation: function () {
            var me = this;
            var context = me.ctx;
            var tickOpts = me.options.ticks;
            var labels = labelsFromTicks(me._ticks);

            // Get the width of each grid by calculating the difference
            // between x offsets between 0 and 1.
            var tickFont = helpers$1.options._parseFont(tickOpts);
            context.font = tickFont.string;

            var labelRotation = tickOpts.minRotation || 0;

            if (labels.length && me.options.display && me.isHorizontal()) {
                var originalLabelWidth = helpers$1.longestText(context, tickFont.string, labels, me.longestTextCache);
                var labelWidth = originalLabelWidth;
                var cosRotation, sinRotation;

                // Allow 3 pixels x2 padding either side for label readability
                var tickWidth = me.getPixelForTick(1) - me.getPixelForTick(0) - 6;

                // Max label rotation can be set or default to 90 - also act as a loop counter
                while (labelWidth > tickWidth && labelRotation < tickOpts.maxRotation) {
                    var angleRadians = helpers$1.toRadians(labelRotation);
                    cosRotation = Math.cos(angleRadians);
                    sinRotation = Math.sin(angleRadians);

                    if (sinRotation * originalLabelWidth > me.maxHeight) {
                        // go back one step
                        labelRotation--;
                        break;
                    }

                    labelRotation++;
                    labelWidth = cosRotation * originalLabelWidth;
                }
            }

            me.labelRotation = labelRotation;
        },
        afterCalculateTickRotation: function () {
            helpers$1.callback(this.options.afterCalculateTickRotation, [this]);
        },

        //

        beforeFit: function () {
            helpers$1.callback(this.options.beforeFit, [this]);
        },
        fit: function () {
            var me = this;
            // Reset
            var minSize = me.minSize = {
                width: 0,
                height: 0
            };

            var labels = labelsFromTicks(me._ticks);

            var opts = me.options;
            var tickOpts = opts.ticks;
            var scaleLabelOpts = opts.scaleLabel;
            var gridLineOpts = opts.gridLines;
            var display = me._isVisible();
            var position = opts.position;
            var isHorizontal = me.isHorizontal();

            var parseFont = helpers$1.options._parseFont;
            var tickFont = parseFont(tickOpts);
            var tickMarkLength = opts.gridLines.tickMarkLength;

            // Width
            if (isHorizontal) {
                // subtract the margins to line up with the chartArea if we are a full width scale
                minSize.width = me.isFullWidth() ? me.maxWidth - me.margins.left - me.margins.right : me.maxWidth;
            } else {
                minSize.width = display && gridLineOpts.drawTicks ? tickMarkLength : 0;
            }

            // height
            if (isHorizontal) {
                minSize.height = display && gridLineOpts.drawTicks ? tickMarkLength : 0;
            } else {
                minSize.height = me.maxHeight; // fill all the height
            }

            // Are we showing a title for the scale?
            if (scaleLabelOpts.display && display) {
                var scaleLabelFont = parseFont(scaleLabelOpts);
                var scaleLabelPadding = helpers$1.options.toPadding(scaleLabelOpts.padding);
                var deltaHeight = scaleLabelFont.lineHeight + scaleLabelPadding.height;

                if (isHorizontal) {
                    minSize.height += deltaHeight;
                } else {
                    minSize.width += deltaHeight;
                }
            }

            // Don't bother fitting the ticks if we are not showing the labels
            if (tickOpts.display && display) {
                var largestTextWidth = helpers$1.longestText(me.ctx, tickFont.string, labels, me.longestTextCache);
                var tallestLabelHeightInLines = helpers$1.numberOfLabelLines(labels);
                var lineSpace = tickFont.size * 0.5;
                var tickPadding = me.options.ticks.padding;

                // Store max number of lines and widest label for _autoSkip
                me._maxLabelLines = tallestLabelHeightInLines;
                me.longestLabelWidth = largestTextWidth;

                if (isHorizontal) {
                    var angleRadians = helpers$1.toRadians(me.labelRotation);
                    var cosRotation = Math.cos(angleRadians);
                    var sinRotation = Math.sin(angleRadians);

                    // TODO - improve this calculation
                    var labelHeight = (sinRotation * largestTextWidth)
                        + (tickFont.lineHeight * tallestLabelHeightInLines)
                        + lineSpace; // padding

                    minSize.height = Math.min(me.maxHeight, minSize.height + labelHeight + tickPadding);

                    me.ctx.font = tickFont.string;
                    var firstLabelWidth = computeTextSize(me.ctx, labels[0], tickFont.string);
                    var lastLabelWidth = computeTextSize(me.ctx, labels[labels.length - 1], tickFont.string);
                    var offsetLeft = me.getPixelForTick(0) - me.left;
                    var offsetRight = me.right - me.getPixelForTick(labels.length - 1);
                    var paddingLeft, paddingRight;

                    // Ensure that our ticks are always inside the canvas. When rotated, ticks are right aligned
                    // which means that the right padding is dominated by the font height
                    if (me.labelRotation !== 0) {
                        paddingLeft = position === 'bottom' ? (cosRotation * firstLabelWidth) : (cosRotation * lineSpace);
                        paddingRight = position === 'bottom' ? (cosRotation * lineSpace) : (cosRotation * lastLabelWidth);
                    } else {
                        paddingLeft = firstLabelWidth / 2;
                        paddingRight = lastLabelWidth / 2;
                    }
                    me.paddingLeft = Math.max(paddingLeft - offsetLeft, 0) + 3; // add 3 px to move away from canvas edges
                    me.paddingRight = Math.max(paddingRight - offsetRight, 0) + 3;
                } else {
                    // A vertical axis is more constrained by the width. Labels are the
                    // dominant factor here, so get that length first and account for padding
                    if (tickOpts.mirror) {
                        largestTextWidth = 0;
                    } else {
                        // use lineSpace for consistency with horizontal axis
                        // tickPadding is not implemented for horizontal
                        largestTextWidth += tickPadding + lineSpace;
                    }

                    minSize.width = Math.min(me.maxWidth, minSize.width + largestTextWidth);

                    me.paddingTop = tickFont.size / 2;
                    me.paddingBottom = tickFont.size / 2;
                }
            }

            me.handleMargins();

            me.width = minSize.width;
            me.height = minSize.height;
        },

        /**
         * Handle margins and padding interactions
         * @private
         */
        handleMargins: function () {
            var me = this;
            if (me.margins) {
                me.paddingLeft = Math.max(me.paddingLeft - me.margins.left, 0);
                me.paddingTop = Math.max(me.paddingTop - me.margins.top, 0);
                me.paddingRight = Math.max(me.paddingRight - me.margins.right, 0);
                me.paddingBottom = Math.max(me.paddingBottom - me.margins.bottom, 0);
            }
        },

        afterFit: function () {
            helpers$1.callback(this.options.afterFit, [this]);
        },

        // Shared Methods
        isHorizontal: function () {
            return this.options.position === 'top' || this.options.position === 'bottom';
        },
        isFullWidth: function () {
            return (this.options.fullWidth);
        },

        // Get the correct value. NaN bad inputs, If the value type is object get the x or y based on whether we are horizontal or not
        getRightValue: function (rawValue) {
            // Null and undefined values first
            if (helpers$1.isNullOrUndef(rawValue)) {
                return NaN;
            }
            // isNaN(object) returns true, so make sure NaN is checking for a number; Discard Infinite values
            if ((typeof rawValue === 'number' || rawValue instanceof Number) && !isFinite(rawValue)) {
                return NaN;
            }
            // If it is in fact an object, dive in one more level
            if (rawValue) {
                if (this.isHorizontal()) {
                    if (rawValue.x !== undefined) {
                        return this.getRightValue(rawValue.x);
                    }
                } else if (rawValue.y !== undefined) {
                    return this.getRightValue(rawValue.y);
                }
            }

            // Value is good, return it
            return rawValue;
        },

        /**
         * Used to get the value to display in the tooltip for the data at the given index
         * @param index
         * @param datasetIndex
         */
        getLabelForIndex: helpers$1.noop,

        /**
         * Returns the location of the given data point. Value can either be an index or a numerical value
         * The coordinate (0, 0) is at the upper-left corner of the canvas
         * @param value
         * @param index
         * @param datasetIndex
         */
        getPixelForValue: helpers$1.noop,

        /**
         * Used to get the data value from a given pixel. This is the inverse of getPixelForValue
         * The coordinate (0, 0) is at the upper-left corner of the canvas
         * @param pixel
         */
        getValueForPixel: helpers$1.noop,

        /**
         * Returns the location of the tick at the given index
         * The coordinate (0, 0) is at the upper-left corner of the canvas
         */
        getPixelForTick: function (index) {
            var me = this;
            var offset = me.options.offset;
            if (me.isHorizontal()) {
                var innerWidth = me.width - (me.paddingLeft + me.paddingRight);
                var tickWidth = innerWidth / Math.max((me._ticks.length - (offset ? 0 : 1)), 1);
                var pixel = (tickWidth * index) + me.paddingLeft;

                if (offset) {
                    pixel += tickWidth / 2;
                }

                var finalVal = me.left + pixel;
                finalVal += me.isFullWidth() ? me.margins.left : 0;
                return finalVal;
            }
            var innerHeight = me.height - (me.paddingTop + me.paddingBottom);
            return me.top + (index * (innerHeight / (me._ticks.length - 1)));
        },

        /**
         * Utility for getting the pixel location of a percentage of scale
         * The coordinate (0, 0) is at the upper-left corner of the canvas
         */
        getPixelForDecimal: function (decimal) {
            var me = this;
            if (me.isHorizontal()) {
                var innerWidth = me.width - (me.paddingLeft + me.paddingRight);
                var valueOffset = (innerWidth * decimal) + me.paddingLeft;

                var finalVal = me.left + valueOffset;
                finalVal += me.isFullWidth() ? me.margins.left : 0;
                return finalVal;
            }
            return me.top + (decimal * me.height);
        },

        /**
         * Returns the pixel for the minimum chart value
         * The coordinate (0, 0) is at the upper-left corner of the canvas
         */
        getBasePixel: function () {
            return this.getPixelForValue(this.getBaseValue());
        },

        getBaseValue: function () {
            var me = this;
            var min = me.min;
            var max = me.max;

            return me.beginAtZero ? 0 :
                min < 0 && max < 0 ? max :
                    min > 0 && max > 0 ? min :
                        0;
        },

        /**
         * Returns a subset of ticks to be plotted to avoid overlapping labels.
         * @private
         */
        _autoSkip: function (ticks) {
            var me = this;
            var isHorizontal = me.isHorizontal();
            var optionTicks = me.options.ticks.minor;
            var tickCount = ticks.length;
            var skipRatio = false;
            var maxTicks = optionTicks.maxTicksLimit;

            // Total space needed to display all ticks. First and last ticks are
            // drawn as their center at end of axis, so tickCount-1
            var ticksLength = me._tickSize() * (tickCount - 1);

            // Axis length
            var axisLength = isHorizontal
                ? me.width - (me.paddingLeft + me.paddingRight)
                : me.height - (me.paddingTop + me.PaddingBottom);

            var result = [];
            var i, tick;

            if (ticksLength > axisLength) {
                skipRatio = 1 + Math.floor(ticksLength / axisLength);
            }

            // if they defined a max number of optionTicks,
            // increase skipRatio until that number is met
            if (tickCount > maxTicks) {
                skipRatio = Math.max(skipRatio, 1 + Math.floor(tickCount / maxTicks));
            }

            for (i = 0; i < tickCount; i++) {
                tick = ticks[i];

                if (skipRatio > 1 && i % skipRatio > 0) {
                    // leave tick in place but make sure it's not displayed (#4635)
                    delete tick.label;
                }
                result.push(tick);
            }
            return result;
        },

        /**
         * @private
         */
        _tickSize: function () {
            var me = this;
            var isHorizontal = me.isHorizontal();
            var optionTicks = me.options.ticks.minor;

            // Calculate space needed by label in axis direction.
            var rot = helpers$1.toRadians(me.labelRotation);
            var cos = Math.abs(Math.cos(rot));
            var sin = Math.abs(Math.sin(rot));

            var padding = optionTicks.autoSkipPadding || 0;
            var w = (me.longestLabelWidth + padding) || 0;

            var tickFont = helpers$1.options._parseFont(optionTicks);
            var h = (me._maxLabelLines * tickFont.lineHeight + padding) || 0;

            // Calculate space needed for 1 tick in axis direction.
            return isHorizontal
                ? h * cos > w * sin ? w / cos : h / sin
                : h * sin < w * cos ? h / cos : w / sin;
        },

        /**
         * @private
         */
        _isVisible: function () {
            var me = this;
            var chart = me.chart;
            var display = me.options.display;
            var i, ilen, meta;

            if (display !== 'auto') {
                return !!display;
            }

            // When 'auto', the scale is visible if at least one associated dataset is visible.
            for (i = 0, ilen = chart.data.datasets.length; i < ilen; ++i) {
                if (chart.isDatasetVisible(i)) {
                    meta = chart.getDatasetMeta(i);
                    if (meta.xAxisID === me.id || meta.yAxisID === me.id) {
                        return true;
                    }
                }
            }

            return false;
        },

        /**
         * Actually draw the scale on the canvas
         * @param {object} chartArea - the area of the chart to draw full grid lines on
         */
        draw: function (chartArea) {
            var me = this;
            var options = me.options;

            if (!me._isVisible()) {
                return;
            }

            var chart = me.chart;
            var context = me.ctx;
            var globalDefaults = core_defaults.global;
            var defaultFontColor = globalDefaults.defaultFontColor;
            var optionTicks = options.ticks.minor;
            var optionMajorTicks = options.ticks.major || optionTicks;
            var gridLines = options.gridLines;
            var scaleLabel = options.scaleLabel;
            var position = options.position;

            var isRotated = me.labelRotation !== 0;
            var isMirrored = optionTicks.mirror;
            var isHorizontal = me.isHorizontal();

            var parseFont = helpers$1.options._parseFont;
            var ticks = optionTicks.display && optionTicks.autoSkip ? me._autoSkip(me.getTicks()) : me.getTicks();
            var tickFontColor = valueOrDefault$9(optionTicks.fontColor, defaultFontColor);
            var tickFont = parseFont(optionTicks);
            var lineHeight = tickFont.lineHeight;
            var majorTickFontColor = valueOrDefault$9(optionMajorTicks.fontColor, defaultFontColor);
            var majorTickFont = parseFont(optionMajorTicks);
            var tickPadding = optionTicks.padding;
            var labelOffset = optionTicks.labelOffset;

            var tl = gridLines.drawTicks ? gridLines.tickMarkLength : 0;

            var scaleLabelFontColor = valueOrDefault$9(scaleLabel.fontColor, defaultFontColor);
            var scaleLabelFont = parseFont(scaleLabel);
            var scaleLabelPadding = helpers$1.options.toPadding(scaleLabel.padding);
            var labelRotationRadians = helpers$1.toRadians(me.labelRotation);

            var itemsToDraw = [];

            var axisWidth = gridLines.drawBorder ? valueAtIndexOrDefault(gridLines.lineWidth, 0, 0) : 0;
            var alignPixel = helpers$1._alignPixel;
            var borderValue, tickStart, tickEnd;

            if (position === 'top') {
                borderValue = alignPixel(chart, me.bottom, axisWidth);
                tickStart = me.bottom - tl;
                tickEnd = borderValue - axisWidth / 2;
            } else if (position === 'bottom') {
                borderValue = alignPixel(chart, me.top, axisWidth);
                tickStart = borderValue + axisWidth / 2;
                tickEnd = me.top + tl;
            } else if (position === 'left') {
                borderValue = alignPixel(chart, me.right, axisWidth);
                tickStart = me.right - tl;
                tickEnd = borderValue - axisWidth / 2;
            } else {
                borderValue = alignPixel(chart, me.left, axisWidth);
                tickStart = borderValue + axisWidth / 2;
                tickEnd = me.left + tl;
            }

            var epsilon = 0.0000001; // 0.0000001 is margin in pixels for Accumulated error.

            helpers$1.each(ticks, function (tick, index) {
                // autoskipper skipped this tick (#4635)
                if (helpers$1.isNullOrUndef(tick.label)) {
                    return;
                }

                var label = tick.label;
                var lineWidth, lineColor, borderDash, borderDashOffset;
                if (index === me.zeroLineIndex && options.offset === gridLines.offsetGridLines) {
                    // Draw the first index specially
                    lineWidth = gridLines.zeroLineWidth;
                    lineColor = gridLines.zeroLineColor;
                    borderDash = gridLines.zeroLineBorderDash || [];
                    borderDashOffset = gridLines.zeroLineBorderDashOffset || 0.0;
                } else {
                    lineWidth = valueAtIndexOrDefault(gridLines.lineWidth, index);
                    lineColor = valueAtIndexOrDefault(gridLines.color, index);
                    borderDash = gridLines.borderDash || [];
                    borderDashOffset = gridLines.borderDashOffset || 0.0;
                }

                // Common properties
                var tx1, ty1, tx2, ty2, x1, y1, x2, y2, labelX, labelY, textOffset, textAlign;
                var labelCount = helpers$1.isArray(label) ? label.length : 1;
                var lineValue = getPixelForGridLine(me, index, gridLines.offsetGridLines);

                if (isHorizontal) {
                    var labelYOffset = tl + tickPadding;

                    if (lineValue < me.left - epsilon) {
                        lineColor = 'rgba(0,0,0,0)';
                    }

                    tx1 = tx2 = x1 = x2 = alignPixel(chart, lineValue, lineWidth);
                    ty1 = tickStart;
                    ty2 = tickEnd;
                    labelX = me.getPixelForTick(index) + labelOffset; // x values for optionTicks (need to consider offsetLabel option)

                    if (position === 'top') {
                        y1 = alignPixel(chart, chartArea.top, axisWidth) + axisWidth / 2;
                        y2 = chartArea.bottom;
                        textOffset = ((!isRotated ? 0.5 : 1) - labelCount) * lineHeight;
                        textAlign = !isRotated ? 'center' : 'left';
                        labelY = me.bottom - labelYOffset;
                    } else {
                        y1 = chartArea.top;
                        y2 = alignPixel(chart, chartArea.bottom, axisWidth) - axisWidth / 2;
                        textOffset = (!isRotated ? 0.5 : 0) * lineHeight;
                        textAlign = !isRotated ? 'center' : 'right';
                        labelY = me.top + labelYOffset;
                    }
                } else {
                    var labelXOffset = (isMirrored ? 0 : tl) + tickPadding;

                    if (lineValue < me.top - epsilon) {
                        lineColor = 'rgba(0,0,0,0)';
                    }

                    tx1 = tickStart;
                    tx2 = tickEnd;
                    ty1 = ty2 = y1 = y2 = alignPixel(chart, lineValue, lineWidth);
                    labelY = me.getPixelForTick(index) + labelOffset;
                    textOffset = (1 - labelCount) * lineHeight / 2;

                    if (position === 'left') {
                        x1 = alignPixel(chart, chartArea.left, axisWidth) + axisWidth / 2;
                        x2 = chartArea.right;
                        textAlign = isMirrored ? 'left' : 'right';
                        labelX = me.right - labelXOffset;
                    } else {
                        x1 = chartArea.left;
                        x2 = alignPixel(chart, chartArea.right, axisWidth) - axisWidth / 2;
                        textAlign = isMirrored ? 'right' : 'left';
                        labelX = me.left + labelXOffset;
                    }
                }

                itemsToDraw.push({
                    tx1: tx1,
                    ty1: ty1,
                    tx2: tx2,
                    ty2: ty2,
                    x1: x1,
                    y1: y1,
                    x2: x2,
                    y2: y2,
                    labelX: labelX,
                    labelY: labelY,
                    glWidth: lineWidth,
                    glColor: lineColor,
                    glBorderDash: borderDash,
                    glBorderDashOffset: borderDashOffset,
                    rotation: -1 * labelRotationRadians,
                    label: label,
                    major: tick.major,
                    textOffset: textOffset,
                    textAlign: textAlign
                });
            });

            // Draw all of the tick labels, tick marks, and grid lines at the correct places
            helpers$1.each(itemsToDraw, function (itemToDraw) {
                var glWidth = itemToDraw.glWidth;
                var glColor = itemToDraw.glColor;

                if (gridLines.display && glWidth && glColor) {
                    context.save();
                    context.lineWidth = glWidth;
                    context.strokeStyle = glColor;
                    if (context.setLineDash) {
                        context.setLineDash(itemToDraw.glBorderDash);
                        context.lineDashOffset = itemToDraw.glBorderDashOffset;
                    }

                    context.beginPath();

                    if (gridLines.drawTicks) {
                        context.moveTo(itemToDraw.tx1, itemToDraw.ty1);
                        context.lineTo(itemToDraw.tx2, itemToDraw.ty2);
                    }

                    if (gridLines.drawOnChartArea) {
                        context.moveTo(itemToDraw.x1, itemToDraw.y1);
                        context.lineTo(itemToDraw.x2, itemToDraw.y2);
                    }

                    context.stroke();
                    context.restore();
                }

                if (optionTicks.display) {
                    // Make sure we draw text in the correct color and font
                    context.save();
                    context.translate(itemToDraw.labelX, itemToDraw.labelY);
                    context.rotate(itemToDraw.rotation);
                    context.font = itemToDraw.major ? majorTickFont.string : tickFont.string;
                    context.fillStyle = itemToDraw.major ? majorTickFontColor : tickFontColor;
                    context.textBaseline = 'middle';
                    context.textAlign = itemToDraw.textAlign;

                    var label = itemToDraw.label;
                    var y = itemToDraw.textOffset;
                    if (helpers$1.isArray(label)) {
                        for (var i = 0; i < label.length; ++i) {
                            // We just make sure the multiline element is a string here..
                            context.fillText('' + label[i], 0, y);
                            y += lineHeight;
                        }
                    } else {
                        context.fillText(label, 0, y);
                    }
                    context.restore();
                }
            });

            if (scaleLabel.display) {
                // Draw the scale label
                var scaleLabelX;
                var scaleLabelY;
                var rotation = 0;
                var halfLineHeight = scaleLabelFont.lineHeight / 2;

                if (isHorizontal) {
                    scaleLabelX = me.left + ((me.right - me.left) / 2); // midpoint of the width
                    scaleLabelY = position === 'bottom'
                        ? me.bottom - halfLineHeight - scaleLabelPadding.bottom
                        : me.top + halfLineHeight + scaleLabelPadding.top;
                } else {
                    var isLeft = position === 'left';
                    scaleLabelX = isLeft
                        ? me.left + halfLineHeight + scaleLabelPadding.top
                        : me.right - halfLineHeight - scaleLabelPadding.top;
                    scaleLabelY = me.top + ((me.bottom - me.top) / 2);
                    rotation = isLeft ? -0.5 * Math.PI : 0.5 * Math.PI;
                }

                context.save();
                context.translate(scaleLabelX, scaleLabelY);
                context.rotate(rotation);
                context.textAlign = 'center';
                context.textBaseline = 'middle';
                context.fillStyle = scaleLabelFontColor; // render in correct colour
                context.font = scaleLabelFont.string;
                context.fillText(scaleLabel.labelString, 0, 0);
                context.restore();
            }

            if (axisWidth) {
                // Draw the line at the edge of the axis
                var firstLineWidth = axisWidth;
                var lastLineWidth = valueAtIndexOrDefault(gridLines.lineWidth, ticks.length - 1, 0);
                var x1, x2, y1, y2;

                if (isHorizontal) {
                    x1 = alignPixel(chart, me.left, firstLineWidth) - firstLineWidth / 2;
                    x2 = alignPixel(chart, me.right, lastLineWidth) + lastLineWidth / 2;
                    y1 = y2 = borderValue;
                } else {
                    y1 = alignPixel(chart, me.top, firstLineWidth) - firstLineWidth / 2;
                    y2 = alignPixel(chart, me.bottom, lastLineWidth) + lastLineWidth / 2;
                    x1 = x2 = borderValue;
                }

                context.lineWidth = axisWidth;
                context.strokeStyle = valueAtIndexOrDefault(gridLines.color, 0);
                context.beginPath();
                context.moveTo(x1, y1);
                context.lineTo(x2, y2);
                context.stroke();
            }
        }
    });

    var defaultConfig = {
        position: 'bottom'
    };

    var scale_category = core_scale.extend({
        /**
        * Internal function to get the correct labels. If data.xLabels or data.yLabels are defined, use those
        * else fall back to data.labels
        * @private
        */
        getLabels: function () {
            var data = this.chart.data;
            return this.options.labels || (this.isHorizontal() ? data.xLabels : data.yLabels) || data.labels;
        },

        determineDataLimits: function () {
            var me = this;
            var labels = me.getLabels();
            me.minIndex = 0;
            me.maxIndex = labels.length - 1;
            var findIndex;

            if (me.options.ticks.min !== undefined) {
                // user specified min value
                findIndex = labels.indexOf(me.options.ticks.min);
                me.minIndex = findIndex !== -1 ? findIndex : me.minIndex;
            }

            if (me.options.ticks.max !== undefined) {
                // user specified max value
                findIndex = labels.indexOf(me.options.ticks.max);
                me.maxIndex = findIndex !== -1 ? findIndex : me.maxIndex;
            }

            me.min = labels[me.minIndex];
            me.max = labels[me.maxIndex];
        },

        buildTicks: function () {
            var me = this;
            var labels = me.getLabels();
            // If we are viewing some subset of labels, slice the original array
            me.ticks = (me.minIndex === 0 && me.maxIndex === labels.length - 1) ? labels : labels.slice(me.minIndex, me.maxIndex + 1);
        },

        getLabelForIndex: function (index, datasetIndex) {
            var me = this;
            var chart = me.chart;

            if (chart.getDatasetMeta(datasetIndex).controller._getValueScaleId() === me.id) {
                return me.getRightValue(chart.data.datasets[datasetIndex].data[index]);
            }

            return me.ticks[index - me.minIndex];
        },

        // Used to get data value locations.  Value can either be an index or a numerical value
        getPixelForValue: function (value, index) {
            var me = this;
            var offset = me.options.offset;
            // 1 is added because we need the length but we have the indexes
            var offsetAmt = Math.max((me.maxIndex + 1 - me.minIndex - (offset ? 0 : 1)), 1);

            // If value is a data object, then index is the index in the data array,
            // not the index of the scale. We need to change that.
            var valueCategory;
            if (value !== undefined && value !== null) {
                valueCategory = me.isHorizontal() ? value.x : value.y;
            }
            if (valueCategory !== undefined || (value !== undefined && isNaN(index))) {
                var labels = me.getLabels();
                value = valueCategory || value;
                var idx = labels.indexOf(value);
                index = idx !== -1 ? idx : index;
            }

            if (me.isHorizontal()) {
                var valueWidth = me.width / offsetAmt;
                var widthOffset = (valueWidth * (index - me.minIndex));

                if (offset) {
                    widthOffset += (valueWidth / 2);
                }

                return me.left + widthOffset;
            }
            var valueHeight = me.height / offsetAmt;
            var heightOffset = (valueHeight * (index - me.minIndex));

            if (offset) {
                heightOffset += (valueHeight / 2);
            }

            return me.top + heightOffset;
        },

        getPixelForTick: function (index) {
            return this.getPixelForValue(this.ticks[index], index + this.minIndex, null);
        },

        getValueForPixel: function (pixel) {
            var me = this;
            var offset = me.options.offset;
            var value;
            var offsetAmt = Math.max((me._ticks.length - (offset ? 0 : 1)), 1);
            var horz = me.isHorizontal();
            var valueDimension = (horz ? me.width : me.height) / offsetAmt;

            pixel -= horz ? me.left : me.top;

            if (offset) {
                pixel -= (valueDimension / 2);
            }

            if (pixel <= 0) {
                value = 0;
            } else {
                value = Math.round(pixel / valueDimension);
            }

            return value + me.minIndex;
        },

        getBasePixel: function () {
            return this.bottom;
        }
    });

    // INTERNAL: static default options, registered in src/index.js
    var _defaults = defaultConfig;
    scale_category._defaults = _defaults;

    var noop = helpers$1.noop;
    var isNullOrUndef = helpers$1.isNullOrUndef;

    /**
     * Generate a set of linear ticks
     * @param generationOptions the options used to generate the ticks
     * @param dataRange the range of the data
     * @returns {number[]} array of tick values
     */
    function generateTicks(generationOptions, dataRange) {
        var ticks = [];
        // To get a "nice" value for the tick spacing, we will use the appropriately named
        // "nice number" algorithm. See https://stackoverflow.com/questions/8506881/nice-label-algorithm-for-charts-with-minimum-ticks
        // for details.

        var MIN_SPACING = 1e-14;
        var stepSize = generationOptions.stepSize;
        var unit = stepSize || 1;
        var maxNumSpaces = generationOptions.maxTicks - 1;
        var min = generationOptions.min;
        var max = generationOptions.max;
        var precision = generationOptions.precision;
        var rmin = dataRange.min;
        var rmax = dataRange.max;
        var spacing = helpers$1.niceNum((rmax - rmin) / maxNumSpaces / unit) * unit;
        var factor, niceMin, niceMax, numSpaces;

        // Beyond MIN_SPACING floating point numbers being to lose precision
        // such that we can't do the math necessary to generate ticks
        if (spacing < MIN_SPACING && isNullOrUndef(min) && isNullOrUndef(max)) {
            return [rmin, rmax];
        }

        numSpaces = Math.ceil(rmax / spacing) - Math.floor(rmin / spacing);
        if (numSpaces > maxNumSpaces) {
            // If the calculated num of spaces exceeds maxNumSpaces, recalculate it
            spacing = helpers$1.niceNum(numSpaces * spacing / maxNumSpaces / unit) * unit;
        }

        if (stepSize || isNullOrUndef(precision)) {
            // If a precision is not specified, calculate factor based on spacing
            factor = Math.pow(10, helpers$1._decimalPlaces(spacing));
        } else {
            // If the user specified a precision, round to that number of decimal places
            factor = Math.pow(10, precision);
            spacing = Math.ceil(spacing * factor) / factor;
        }

        niceMin = Math.floor(rmin / spacing) * spacing;
        niceMax = Math.ceil(rmax / spacing) * spacing;

        // If min, max and stepSize is set and they make an evenly spaced scale use it.
        if (stepSize) {
            // If very close to our whole number, use it.
            if (!isNullOrUndef(min) && helpers$1.almostWhole(min / spacing, spacing / 1000)) {
                niceMin = min;
            }
            if (!isNullOrUndef(max) && helpers$1.almostWhole(max / spacing, spacing / 1000)) {
                niceMax = max;
            }
        }

        numSpaces = (niceMax - niceMin) / spacing;
        // If very close to our rounded value, use it.
        if (helpers$1.almostEquals(numSpaces, Math.round(numSpaces), spacing / 1000)) {
            numSpaces = Math.round(numSpaces);
        } else {
            numSpaces = Math.ceil(numSpaces);
        }

        niceMin = Math.round(niceMin * factor) / factor;
        niceMax = Math.round(niceMax * factor) / factor;
        ticks.push(isNullOrUndef(min) ? niceMin : min);
        for (var j = 1; j < numSpaces; ++j) {
            ticks.push(Math.round((niceMin + j * spacing) * factor) / factor);
        }
        ticks.push(isNullOrUndef(max) ? niceMax : max);

        return ticks;
    }

    var scale_linearbase = core_scale.extend({
        getRightValue: function (value) {
            if (typeof value === 'string') {
                return +value;
            }
            return core_scale.prototype.getRightValue.call(this, value);
        },

        handleTickRangeOptions: function () {
            var me = this;
            var opts = me.options;
            var tickOpts = opts.ticks;

            // If we are forcing it to begin at 0, but 0 will already be rendered on the chart,
            // do nothing since that would make the chart weird. If the user really wants a weird chart
            // axis, they can manually override it
            if (tickOpts.beginAtZero) {
                var minSign = helpers$1.sign(me.min);
                var maxSign = helpers$1.sign(me.max);

                if (minSign < 0 && maxSign < 0) {
                    // move the top up to 0
                    me.max = 0;
                } else if (minSign > 0 && maxSign > 0) {
                    // move the bottom down to 0
                    me.min = 0;
                }
            }

            var setMin = tickOpts.min !== undefined || tickOpts.suggestedMin !== undefined;
            var setMax = tickOpts.max !== undefined || tickOpts.suggestedMax !== undefined;

            if (tickOpts.min !== undefined) {
                me.min = tickOpts.min;
            } else if (tickOpts.suggestedMin !== undefined) {
                if (me.min === null) {
                    me.min = tickOpts.suggestedMin;
                } else {
                    me.min = Math.min(me.min, tickOpts.suggestedMin);
                }
            }

            if (tickOpts.max !== undefined) {
                me.max = tickOpts.max;
            } else if (tickOpts.suggestedMax !== undefined) {
                if (me.max === null) {
                    me.max = tickOpts.suggestedMax;
                } else {
                    me.max = Math.max(me.max, tickOpts.suggestedMax);
                }
            }

            if (setMin !== setMax) {
                // We set the min or the max but not both.
                // So ensure that our range is good
                // Inverted or 0 length range can happen when
                // ticks.min is set, and no datasets are visible
                if (me.min >= me.max) {
                    if (setMin) {
                        me.max = me.min + 1;
                    } else {
                        me.min = me.max - 1;
                    }
                }
            }

            if (me.min === me.max) {
                me.max++;

                if (!tickOpts.beginAtZero) {
                    me.min--;
                }
            }
        },

        getTickLimit: function () {
            var me = this;
            var tickOpts = me.options.ticks;
            var stepSize = tickOpts.stepSize;
            var maxTicksLimit = tickOpts.maxTicksLimit;
            var maxTicks;

            if (stepSize) {
                maxTicks = Math.ceil(me.max / stepSize) - Math.floor(me.min / stepSize) + 1;
            } else {
                maxTicks = me._computeTickLimit();
                maxTicksLimit = maxTicksLimit || 11;
            }

            if (maxTicksLimit) {
                maxTicks = Math.min(maxTicksLimit, maxTicks);
            }

            return maxTicks;
        },

        _computeTickLimit: function () {
            return Number.POSITIVE_INFINITY;
        },

        handleDirectionalChanges: noop,

        buildTicks: function () {
            var me = this;
            var opts = me.options;
            var tickOpts = opts.ticks;

            // Figure out what the max number of ticks we can support it is based on the size of
            // the axis area. For now, we say that the minimum tick spacing in pixels must be 40
            // We also limit the maximum number of ticks to 11 which gives a nice 10 squares on
            // the graph. Make sure we always have at least 2 ticks
            var maxTicks = me.getTickLimit();
            maxTicks = Math.max(2, maxTicks);

            var numericGeneratorOptions = {
                maxTicks: maxTicks,
                min: tickOpts.min,
                max: tickOpts.max,
                precision: tickOpts.precision,
                stepSize: helpers$1.valueOrDefault(tickOpts.fixedStepSize, tickOpts.stepSize)
            };
            var ticks = me.ticks = generateTicks(numericGeneratorOptions, me);

            me.handleDirectionalChanges();

            // At this point, we need to update our max and min given the tick values since we have expanded the
            // range of the scale
            me.max = helpers$1.max(ticks);
            me.min = helpers$1.min(ticks);

            if (tickOpts.reverse) {
                ticks.reverse();

                me.start = me.max;
                me.end = me.min;
            } else {
                me.start = me.min;
                me.end = me.max;
            }
        },

        convertTicksToLabels: function () {
            var me = this;
            me.ticksAsNumbers = me.ticks.slice();
            me.zeroLineIndex = me.ticks.indexOf(0);

            core_scale.prototype.convertTicksToLabels.call(me);
        }
    });

    var defaultConfig$1 = {
        position: 'left',
        ticks: {
            callback: core_ticks.formatters.linear
        }
    };

    var scale_linear = scale_linearbase.extend({
        determineDataLimits: function () {
            var me = this;
            var opts = me.options;
            var chart = me.chart;
            var data = chart.data;
            var datasets = data.datasets;
            var isHorizontal = me.isHorizontal();
            var DEFAULT_MIN = 0;
            var DEFAULT_MAX = 1;

            function IDMatches(meta) {
                return isHorizontal ? meta.xAxisID === me.id : meta.yAxisID === me.id;
            }

            // First Calculate the range
            me.min = null;
            me.max = null;

            var hasStacks = opts.stacked;
            if (hasStacks === undefined) {
                helpers$1.each(datasets, function (dataset, datasetIndex) {
                    if (hasStacks) {
                        return;
                    }

                    var meta = chart.getDatasetMeta(datasetIndex);
                    if (chart.isDatasetVisible(datasetIndex) && IDMatches(meta) &&
                        meta.stack !== undefined) {
                        hasStacks = true;
                    }
                });
            }

            if (opts.stacked || hasStacks) {
                var valuesPerStack = {};

                helpers$1.each(datasets, function (dataset, datasetIndex) {
                    var meta = chart.getDatasetMeta(datasetIndex);
                    var key = [
                        meta.type,
                        // we have a separate stack for stack=undefined datasets when the opts.stacked is undefined
                        ((opts.stacked === undefined && meta.stack === undefined) ? datasetIndex : ''),
                        meta.stack
                    ].join('.');

                    if (valuesPerStack[key] === undefined) {
                        valuesPerStack[key] = {
                            positiveValues: [],
                            negativeValues: []
                        };
                    }

                    // Store these per type
                    var positiveValues = valuesPerStack[key].positiveValues;
                    var negativeValues = valuesPerStack[key].negativeValues;

                    if (chart.isDatasetVisible(datasetIndex) && IDMatches(meta)) {
                        helpers$1.each(dataset.data, function (rawValue, index) {
                            var value = +me.getRightValue(rawValue);
                            if (isNaN(value) || meta.data[index].hidden) {
                                return;
                            }

                            positiveValues[index] = positiveValues[index] || 0;
                            negativeValues[index] = negativeValues[index] || 0;

                            if (opts.relativePoints) {
                                positiveValues[index] = 100;
                            } else if (value < 0) {
                                negativeValues[index] += value;
                            } else {
                                positiveValues[index] += value;
                            }
                        });
                    }
                });

                helpers$1.each(valuesPerStack, function (valuesForType) {
                    var values = valuesForType.positiveValues.concat(valuesForType.negativeValues);
                    var minVal = helpers$1.min(values);
                    var maxVal = helpers$1.max(values);
                    me.min = me.min === null ? minVal : Math.min(me.min, minVal);
                    me.max = me.max === null ? maxVal : Math.max(me.max, maxVal);
                });

            } else {
                helpers$1.each(datasets, function (dataset, datasetIndex) {
                    var meta = chart.getDatasetMeta(datasetIndex);
                    if (chart.isDatasetVisible(datasetIndex) && IDMatches(meta)) {
                        helpers$1.each(dataset.data, function (rawValue, index) {
                            var value = +me.getRightValue(rawValue);
                            if (isNaN(value) || meta.data[index].hidden) {
                                return;
                            }

                            if (me.min === null) {
                                me.min = value;
                            } else if (value < me.min) {
                                me.min = value;
                            }

                            if (me.max === null) {
                                me.max = value;
                            } else if (value > me.max) {
                                me.max = value;
                            }
                        });
                    }
                });
            }

            me.min = isFinite(me.min) && !isNaN(me.min) ? me.min : DEFAULT_MIN;
            me.max = isFinite(me.max) && !isNaN(me.max) ? me.max : DEFAULT_MAX;

            // Common base implementation to handle ticks.min, ticks.max, ticks.beginAtZero
            this.handleTickRangeOptions();
        },

        // Returns the maximum number of ticks based on the scale dimension
        _computeTickLimit: function () {
            var me = this;
            var tickFont;

            if (me.isHorizontal()) {
                return Math.ceil(me.width / 40);
            }
            tickFont = helpers$1.options._parseFont(me.options.ticks);
            return Math.ceil(me.height / tickFont.lineHeight);
        },

        // Called after the ticks are built. We need
        handleDirectionalChanges: function () {
            if (!this.isHorizontal()) {
                // We are in a vertical orientation. The top value is the highest. So reverse the array
                this.ticks.reverse();
            }
        },

        getLabelForIndex: function (index, datasetIndex) {
            return +this.getRightValue(this.chart.data.datasets[datasetIndex].data[index]);
        },

        // Utils
        getPixelForValue: function (value) {
            // This must be called after fit has been run so that
            // this.left, this.top, this.right, and this.bottom have been defined
            var me = this;
            var start = me.start;

            var rightValue = +me.getRightValue(value);
            var pixel;
            var range = me.end - start;

            if (me.isHorizontal()) {
                pixel = me.left + (me.width / range * (rightValue - start));
            } else {
                pixel = me.bottom - (me.height / range * (rightValue - start));
            }
            return pixel;
        },

        getValueForPixel: function (pixel) {
            var me = this;
            var isHorizontal = me.isHorizontal();
            var innerDimension = isHorizontal ? me.width : me.height;
            var offset = (isHorizontal ? pixel - me.left : me.bottom - pixel) / innerDimension;
            return me.start + ((me.end - me.start) * offset);
        },

        getPixelForTick: function (index) {
            return this.getPixelForValue(this.ticksAsNumbers[index]);
        }
    });

    // INTERNAL: static default options, registered in src/index.js
    var _defaults$1 = defaultConfig$1;
    scale_linear._defaults = _defaults$1;

    var valueOrDefault$a = helpers$1.valueOrDefault;

    /**
     * Generate a set of logarithmic ticks
     * @param generationOptions the options used to generate the ticks
     * @param dataRange the range of the data
     * @returns {number[]} array of tick values
     */
    function generateTicks$1(generationOptions, dataRange) {
        var ticks = [];

        var tickVal = valueOrDefault$a(generationOptions.min, Math.pow(10, Math.floor(helpers$1.log10(dataRange.min))));

        var endExp = Math.floor(helpers$1.log10(dataRange.max));
        var endSignificand = Math.ceil(dataRange.max / Math.pow(10, endExp));
        var exp, significand;

        if (tickVal === 0) {
            exp = Math.floor(helpers$1.log10(dataRange.minNotZero));
            significand = Math.floor(dataRange.minNotZero / Math.pow(10, exp));

            ticks.push(tickVal);
            tickVal = significand * Math.pow(10, exp);
        } else {
            exp = Math.floor(helpers$1.log10(tickVal));
            significand = Math.floor(tickVal / Math.pow(10, exp));
        }
        var precision = exp < 0 ? Math.pow(10, Math.abs(exp)) : 1;

        do {
            ticks.push(tickVal);

            ++significand;
            if (significand === 10) {
                significand = 1;
                ++exp;
                precision = exp >= 0 ? 1 : precision;
            }

            tickVal = Math.round(significand * Math.pow(10, exp) * precision) / precision;
        } while (exp < endExp || (exp === endExp && significand < endSignificand));

        var lastTick = valueOrDefault$a(generationOptions.max, tickVal);
        ticks.push(lastTick);

        return ticks;
    }

    var defaultConfig$2 = {
        position: 'left',

        // label settings
        ticks: {
            callback: core_ticks.formatters.logarithmic
        }
    };

    // TODO(v3): change this to positiveOrDefault
    function nonNegativeOrDefault(value, defaultValue) {
        return helpers$1.isFinite(value) && value >= 0 ? value : defaultValue;
    }

    var scale_logarithmic = core_scale.extend({
        determineDataLimits: function () {
            var me = this;
            var opts = me.options;
            var chart = me.chart;
            var data = chart.data;
            var datasets = data.datasets;
            var isHorizontal = me.isHorizontal();
            function IDMatches(meta) {
                return isHorizontal ? meta.xAxisID === me.id : meta.yAxisID === me.id;
            }

            // Calculate Range
            me.min = null;
            me.max = null;
            me.minNotZero = null;

            var hasStacks = opts.stacked;
            if (hasStacks === undefined) {
                helpers$1.each(datasets, function (dataset, datasetIndex) {
                    if (hasStacks) {
                        return;
                    }

                    var meta = chart.getDatasetMeta(datasetIndex);
                    if (chart.isDatasetVisible(datasetIndex) && IDMatches(meta) &&
                        meta.stack !== undefined) {
                        hasStacks = true;
                    }
                });
            }

            if (opts.stacked || hasStacks) {
                var valuesPerStack = {};

                helpers$1.each(datasets, function (dataset, datasetIndex) {
                    var meta = chart.getDatasetMeta(datasetIndex);
                    var key = [
                        meta.type,
                        // we have a separate stack for stack=undefined datasets when the opts.stacked is undefined
                        ((opts.stacked === undefined && meta.stack === undefined) ? datasetIndex : ''),
                        meta.stack
                    ].join('.');

                    if (chart.isDatasetVisible(datasetIndex) && IDMatches(meta)) {
                        if (valuesPerStack[key] === undefined) {
                            valuesPerStack[key] = [];
                        }

                        helpers$1.each(dataset.data, function (rawValue, index) {
                            var values = valuesPerStack[key];
                            var value = +me.getRightValue(rawValue);
                            // invalid, hidden and negative values are ignored
                            if (isNaN(value) || meta.data[index].hidden || value < 0) {
                                return;
                            }
                            values[index] = values[index] || 0;
                            values[index] += value;
                        });
                    }
                });

                helpers$1.each(valuesPerStack, function (valuesForType) {
                    if (valuesForType.length > 0) {
                        var minVal = helpers$1.min(valuesForType);
                        var maxVal = helpers$1.max(valuesForType);
                        me.min = me.min === null ? minVal : Math.min(me.min, minVal);
                        me.max = me.max === null ? maxVal : Math.max(me.max, maxVal);
                    }
                });

            } else {
                helpers$1.each(datasets, function (dataset, datasetIndex) {
                    var meta = chart.getDatasetMeta(datasetIndex);
                    if (chart.isDatasetVisible(datasetIndex) && IDMatches(meta)) {
                        helpers$1.each(dataset.data, function (rawValue, index) {
                            var value = +me.getRightValue(rawValue);
                            // invalid, hidden and negative values are ignored
                            if (isNaN(value) || meta.data[index].hidden || value < 0) {
                                return;
                            }

                            if (me.min === null) {
                                me.min = value;
                            } else if (value < me.min) {
                                me.min = value;
                            }

                            if (me.max === null) {
                                me.max = value;
                            } else if (value > me.max) {
                                me.max = value;
                            }

                            if (value !== 0 && (me.minNotZero === null || value < me.minNotZero)) {
                                me.minNotZero = value;
                            }
                        });
                    }
                });
            }

            // Common base implementation to handle ticks.min, ticks.max
            this.handleTickRangeOptions();
        },

        handleTickRangeOptions: function () {
            var me = this;
            var tickOpts = me.options.ticks;
            var DEFAULT_MIN = 1;
            var DEFAULT_MAX = 10;

            me.min = nonNegativeOrDefault(tickOpts.min, me.min);
            me.max = nonNegativeOrDefault(tickOpts.max, me.max);

            if (me.min === me.max) {
                if (me.min !== 0 && me.min !== null) {
                    me.min = Math.pow(10, Math.floor(helpers$1.log10(me.min)) - 1);
                    me.max = Math.pow(10, Math.floor(helpers$1.log10(me.max)) + 1);
                } else {
                    me.min = DEFAULT_MIN;
                    me.max = DEFAULT_MAX;
                }
            }
            if (me.min === null) {
                me.min = Math.pow(10, Math.floor(helpers$1.log10(me.max)) - 1);
            }
            if (me.max === null) {
                me.max = me.min !== 0
                    ? Math.pow(10, Math.floor(helpers$1.log10(me.min)) + 1)
                    : DEFAULT_MAX;
            }
            if (me.minNotZero === null) {
                if (me.min > 0) {
                    me.minNotZero = me.min;
                } else if (me.max < 1) {
                    me.minNotZero = Math.pow(10, Math.floor(helpers$1.log10(me.max)));
                } else {
                    me.minNotZero = DEFAULT_MIN;
                }
            }
        },

        buildTicks: function () {
            var me = this;
            var tickOpts = me.options.ticks;
            var reverse = !me.isHorizontal();

            var generationOptions = {
                min: nonNegativeOrDefault(tickOpts.min),
                max: nonNegativeOrDefault(tickOpts.max)
            };
            var ticks = me.ticks = generateTicks$1(generationOptions, me);

            // At this point, we need to update our max and min given the tick values since we have expanded the
            // range of the scale
            me.max = helpers$1.max(ticks);
            me.min = helpers$1.min(ticks);

            if (tickOpts.reverse) {
                reverse = !reverse;
                me.start = me.max;
                me.end = me.min;
            } else {
                me.start = me.min;
                me.end = me.max;
            }
            if (reverse) {
                ticks.reverse();
            }
        },

        convertTicksToLabels: function () {
            this.tickValues = this.ticks.slice();

            core_scale.prototype.convertTicksToLabels.call(this);
        },

        // Get the correct tooltip label
        getLabelForIndex: function (index, datasetIndex) {
            return +this.getRightValue(this.chart.data.datasets[datasetIndex].data[index]);
        },

        getPixelForTick: function (index) {
            return this.getPixelForValue(this.tickValues[index]);
        },

        /**
         * Returns the value of the first tick.
         * @param {number} value - The minimum not zero value.
         * @return {number} The first tick value.
         * @private
         */
        _getFirstTickValue: function (value) {
            var exp = Math.floor(helpers$1.log10(value));
            var significand = Math.floor(value / Math.pow(10, exp));

            return significand * Math.pow(10, exp);
        },

        getPixelForValue: function (value) {
            var me = this;
            var tickOpts = me.options.ticks;
            var reverse = tickOpts.reverse;
            var log10 = helpers$1.log10;
            var firstTickValue = me._getFirstTickValue(me.minNotZero);
            var offset = 0;
            var innerDimension, pixel, start, end, sign;

            value = +me.getRightValue(value);
            if (reverse) {
                start = me.end;
                end = me.start;
                sign = -1;
            } else {
                start = me.start;
                end = me.end;
                sign = 1;
            }
            if (me.isHorizontal()) {
                innerDimension = me.width;
                pixel = reverse ? me.right : me.left;
            } else {
                innerDimension = me.height;
                sign *= -1; // invert, since the upper-left corner of the canvas is at pixel (0, 0)
                pixel = reverse ? me.top : me.bottom;
            }
            if (value !== start) {
                if (start === 0) { // include zero tick
                    offset = valueOrDefault$a(tickOpts.fontSize, core_defaults.global.defaultFontSize);
                    innerDimension -= offset;
                    start = firstTickValue;
                }
                if (value !== 0) {
                    offset += innerDimension / (log10(end) - log10(start)) * (log10(value) - log10(start));
                }
                pixel += sign * offset;
            }
            return pixel;
        },

        getValueForPixel: function (pixel) {
            var me = this;
            var tickOpts = me.options.ticks;
            var reverse = tickOpts.reverse;
            var log10 = helpers$1.log10;
            var firstTickValue = me._getFirstTickValue(me.minNotZero);
            var innerDimension, start, end, value;

            if (reverse) {
                start = me.end;
                end = me.start;
            } else {
                start = me.start;
                end = me.end;
            }
            if (me.isHorizontal()) {
                innerDimension = me.width;
                value = reverse ? me.right - pixel : pixel - me.left;
            } else {
                innerDimension = me.height;
                value = reverse ? pixel - me.top : me.bottom - pixel;
            }
            if (value !== start) {
                if (start === 0) { // include zero tick
                    var offset = valueOrDefault$a(tickOpts.fontSize, core_defaults.global.defaultFontSize);
                    value -= offset;
                    innerDimension -= offset;
                    start = firstTickValue;
                }
                value *= log10(end) - log10(start);
                value /= innerDimension;
                value = Math.pow(10, log10(start) + value);
            }
            return value;
        }
    });

    // INTERNAL: static default options, registered in src/index.js
    var _defaults$2 = defaultConfig$2;
    scale_logarithmic._defaults = _defaults$2;

    var valueOrDefault$b = helpers$1.valueOrDefault;
    var valueAtIndexOrDefault$1 = helpers$1.valueAtIndexOrDefault;
    var resolve$7 = helpers$1.options.resolve;

    var defaultConfig$3 = {
        display: true,

        // Boolean - Whether to animate scaling the chart from the centre
        animate: true,
        position: 'chartArea',

        angleLines: {
            display: true,
            color: 'rgba(0, 0, 0, 0.1)',
            lineWidth: 1,
            borderDash: [],
            borderDashOffset: 0.0
        },

        gridLines: {
            circular: false
        },

        // label settings
        ticks: {
            // Boolean - Show a backdrop to the scale label
            showLabelBackdrop: true,

            // String - The colour of the label backdrop
            backdropColor: 'rgba(255,255,255,0.75)',

            // Number - The backdrop padding above & below the label in pixels
            backdropPaddingY: 2,

            // Number - The backdrop padding to the side of the label in pixels
            backdropPaddingX: 2,

            callback: core_ticks.formatters.linear
        },

        pointLabels: {
            // Boolean - if true, show point labels
            display: true,

            // Number - Point label font size in pixels
            fontSize: 10,

            // Function - Used to convert point labels
            callback: function (label) {
                return label;
            }
        }
    };

    function getValueCount(scale) {
        var opts = scale.options;
        return opts.angleLines.display || opts.pointLabels.display ? scale.chart.data.labels.length : 0;
    }

    function getTickBackdropHeight(opts) {
        var tickOpts = opts.ticks;

        if (tickOpts.display && opts.display) {
            return valueOrDefault$b(tickOpts.fontSize, core_defaults.global.defaultFontSize) + tickOpts.backdropPaddingY * 2;
        }
        return 0;
    }

    function measureLabelSize(ctx, lineHeight, label) {
        if (helpers$1.isArray(label)) {
            return {
                w: helpers$1.longestText(ctx, ctx.font, label),
                h: label.length * lineHeight
            };
        }

        return {
            w: ctx.measureText(label).width,
            h: lineHeight
        };
    }

    function determineLimits(angle, pos, size, min, max) {
        if (angle === min || angle === max) {
            return {
                start: pos - (size / 2),
                end: pos + (size / 2)
            };
        } else if (angle < min || angle > max) {
            return {
                start: pos - size,
                end: pos
            };
        }

        return {
            start: pos,
            end: pos + size
        };
    }

    /**
     * Helper function to fit a radial linear scale with point labels
     */
    function fitWithPointLabels(scale) {

        // Right, this is really confusing and there is a lot of maths going on here
        // The gist of the problem is here: https://gist.github.com/nnnick/696cc9c55f4b0beb8fe9
        //
        // Reaction: https://dl.dropboxusercontent.com/u/34601363/toomuchscience.gif
        //
        // Solution:
        //
        // We assume the radius of the polygon is half the size of the canvas at first
        // at each index we check if the text overlaps.
        //
        // Where it does, we store that angle and that index.
        //
        // After finding the largest index and angle we calculate how much we need to remove
        // from the shape radius to move the point inwards by that x.
        //
        // We average the left and right distances to get the maximum shape radius that can fit in the box
        // along with labels.
        //
        // Once we have that, we can find the centre point for the chart, by taking the x text protrusion
        // on each side, removing that from the size, halving it and adding the left x protrusion width.
        //
        // This will mean we have a shape fitted to the canvas, as large as it can be with the labels
        // and position it in the most space efficient manner
        //
        // https://dl.dropboxusercontent.com/u/34601363/yeahscience.gif

        var plFont = helpers$1.options._parseFont(scale.options.pointLabels);

        // Get maximum radius of the polygon. Either half the height (minus the text width) or half the width.
        // Use this to calculate the offset + change. - Make sure L/R protrusion is at least 0 to stop issues with centre points
        var furthestLimits = {
            l: 0,
            r: scale.width,
            t: 0,
            b: scale.height - scale.paddingTop
        };
        var furthestAngles = {};
        var i, textSize, pointPosition;

        scale.ctx.font = plFont.string;
        scale._pointLabelSizes = [];

        var valueCount = getValueCount(scale);
        for (i = 0; i < valueCount; i++) {
            pointPosition = scale.getPointPosition(i, scale.drawingArea + 5);
            textSize = measureLabelSize(scale.ctx, plFont.lineHeight, scale.pointLabels[i] || '');
            scale._pointLabelSizes[i] = textSize;

            // Add quarter circle to make degree 0 mean top of circle
            var angleRadians = scale.getIndexAngle(i);
            var angle = helpers$1.toDegrees(angleRadians) % 360;
            var hLimits = determineLimits(angle, pointPosition.x, textSize.w, 0, 180);
            var vLimits = determineLimits(angle, pointPosition.y, textSize.h, 90, 270);

            if (hLimits.start < furthestLimits.l) {
                furthestLimits.l = hLimits.start;
                furthestAngles.l = angleRadians;
            }

            if (hLimits.end > furthestLimits.r) {
                furthestLimits.r = hLimits.end;
                furthestAngles.r = angleRadians;
            }

            if (vLimits.start < furthestLimits.t) {
                furthestLimits.t = vLimits.start;
                furthestAngles.t = angleRadians;
            }

            if (vLimits.end > furthestLimits.b) {
                furthestLimits.b = vLimits.end;
                furthestAngles.b = angleRadians;
            }
        }

        scale.setReductions(scale.drawingArea, furthestLimits, furthestAngles);
    }

    function getTextAlignForAngle(angle) {
        if (angle === 0 || angle === 180) {
            return 'center';
        } else if (angle < 180) {
            return 'left';
        }

        return 'right';
    }

    function fillText(ctx, text, position, lineHeight) {
        var y = position.y + lineHeight / 2;
        var i, ilen;

        if (helpers$1.isArray(text)) {
            for (i = 0, ilen = text.length; i < ilen; ++i) {
                ctx.fillText(text[i], position.x, y);
                y += lineHeight;
            }
        } else {
            ctx.fillText(text, position.x, y);
        }
    }

    function adjustPointPositionForLabelHeight(angle, textSize, position) {
        if (angle === 90 || angle === 270) {
            position.y -= (textSize.h / 2);
        } else if (angle > 270 || angle < 90) {
            position.y -= textSize.h;
        }
    }

    function drawPointLabels(scale) {
        var ctx = scale.ctx;
        var opts = scale.options;
        var angleLineOpts = opts.angleLines;
        var gridLineOpts = opts.gridLines;
        var pointLabelOpts = opts.pointLabels;
        var lineWidth = valueOrDefault$b(angleLineOpts.lineWidth, gridLineOpts.lineWidth);
        var lineColor = valueOrDefault$b(angleLineOpts.color, gridLineOpts.color);
        var tickBackdropHeight = getTickBackdropHeight(opts);

        ctx.save();
        ctx.lineWidth = lineWidth;
        ctx.strokeStyle = lineColor;
        if (ctx.setLineDash) {
            ctx.setLineDash(resolve$7([angleLineOpts.borderDash, gridLineOpts.borderDash, []]));
            ctx.lineDashOffset = resolve$7([angleLineOpts.borderDashOffset, gridLineOpts.borderDashOffset, 0.0]);
        }

        var outerDistance = scale.getDistanceFromCenterForValue(opts.ticks.reverse ? scale.min : scale.max);

        // Point Label Font
        var plFont = helpers$1.options._parseFont(pointLabelOpts);

        ctx.font = plFont.string;
        ctx.textBaseline = 'middle';

        for (var i = getValueCount(scale) - 1; i >= 0; i--) {
            if (angleLineOpts.display && lineWidth && lineColor) {
                var outerPosition = scale.getPointPosition(i, outerDistance);
                ctx.beginPath();
                ctx.moveTo(scale.xCenter, scale.yCenter);
                ctx.lineTo(outerPosition.x, outerPosition.y);
                ctx.stroke();
            }

            if (pointLabelOpts.display) {
                // Extra pixels out for some label spacing
                var extra = (i === 0 ? tickBackdropHeight / 2 : 0);
                var pointLabelPosition = scale.getPointPosition(i, outerDistance + extra + 5);

                // Keep this in loop since we may support array properties here
                var pointLabelFontColor = valueAtIndexOrDefault$1(pointLabelOpts.fontColor, i, core_defaults.global.defaultFontColor);
                ctx.fillStyle = pointLabelFontColor;

                var angleRadians = scale.getIndexAngle(i);
                var angle = helpers$1.toDegrees(angleRadians);
                ctx.textAlign = getTextAlignForAngle(angle);
                adjustPointPositionForLabelHeight(angle, scale._pointLabelSizes[i], pointLabelPosition);
                fillText(ctx, scale.pointLabels[i] || '', pointLabelPosition, plFont.lineHeight);
            }
        }
        ctx.restore();
    }

    function drawRadiusLine(scale, gridLineOpts, radius, index) {
        var ctx = scale.ctx;
        var circular = gridLineOpts.circular;
        var valueCount = getValueCount(scale);
        var lineColor = valueAtIndexOrDefault$1(gridLineOpts.color, index - 1);
        var lineWidth = valueAtIndexOrDefault$1(gridLineOpts.lineWidth, index - 1);
        var pointPosition;

        if ((!circular && !valueCount) || !lineColor || !lineWidth) {
            return;
        }

        ctx.save();
        ctx.strokeStyle = lineColor;
        ctx.lineWidth = lineWidth;
        if (ctx.setLineDash) {
            ctx.setLineDash(gridLineOpts.borderDash || []);
            ctx.lineDashOffset = gridLineOpts.borderDashOffset || 0.0;
        }

        ctx.beginPath();
        if (circular) {
            // Draw circular arcs between the points
            ctx.arc(scale.xCenter, scale.yCenter, radius, 0, Math.PI * 2);
        } else {
            // Draw straight lines connecting each index
            pointPosition = scale.getPointPosition(0, radius);
            ctx.moveTo(pointPosition.x, pointPosition.y);

            for (var i = 1; i < valueCount; i++) {
                pointPosition = scale.getPointPosition(i, radius);
                ctx.lineTo(pointPosition.x, pointPosition.y);
            }
        }
        ctx.closePath();
        ctx.stroke();
        ctx.restore();
    }

    function numberOrZero(param) {
        return helpers$1.isNumber(param) ? param : 0;
    }

    var scale_radialLinear = scale_linearbase.extend({
        setDimensions: function () {
            var me = this;

            // Set the unconstrained dimension before label rotation
            me.width = me.maxWidth;
            me.height = me.maxHeight;
            me.paddingTop = getTickBackdropHeight(me.options) / 2;
            me.xCenter = Math.floor(me.width / 2);
            me.yCenter = Math.floor((me.height - me.paddingTop) / 2);
            me.drawingArea = Math.min(me.height - me.paddingTop, me.width) / 2;
        },

        determineDataLimits: function () {
            var me = this;
            var chart = me.chart;
            var min = Number.POSITIVE_INFINITY;
            var max = Number.NEGATIVE_INFINITY;

            helpers$1.each(chart.data.datasets, function (dataset, datasetIndex) {
                if (chart.isDatasetVisible(datasetIndex)) {
                    var meta = chart.getDatasetMeta(datasetIndex);

                    helpers$1.each(dataset.data, function (rawValue, index) {
                        var value = +me.getRightValue(rawValue);
                        if (isNaN(value) || meta.data[index].hidden) {
                            return;
                        }

                        min = Math.min(value, min);
                        max = Math.max(value, max);
                    });
                }
            });

            me.min = (min === Number.POSITIVE_INFINITY ? 0 : min);
            me.max = (max === Number.NEGATIVE_INFINITY ? 0 : max);

            // Common base implementation to handle ticks.min, ticks.max, ticks.beginAtZero
            me.handleTickRangeOptions();
        },

        // Returns the maximum number of ticks based on the scale dimension
        _computeTickLimit: function () {
            return Math.ceil(this.drawingArea / getTickBackdropHeight(this.options));
        },

        convertTicksToLabels: function () {
            var me = this;

            scale_linearbase.prototype.convertTicksToLabels.call(me);

            // Point labels
            me.pointLabels = me.chart.data.labels.map(me.options.pointLabels.callback, me);
        },

        getLabelForIndex: function (index, datasetIndex) {
            return +this.getRightValue(this.chart.data.datasets[datasetIndex].data[index]);
        },

        fit: function () {
            var me = this;
            var opts = me.options;

            if (opts.display && opts.pointLabels.display) {
                fitWithPointLabels(me);
            } else {
                me.setCenterPoint(0, 0, 0, 0);
            }
        },

        /**
         * Set radius reductions and determine new radius and center point
         * @private
         */
        setReductions: function (largestPossibleRadius, furthestLimits, furthestAngles) {
            var me = this;
            var radiusReductionLeft = furthestLimits.l / Math.sin(furthestAngles.l);
            var radiusReductionRight = Math.max(furthestLimits.r - me.width, 0) / Math.sin(furthestAngles.r);
            var radiusReductionTop = -furthestLimits.t / Math.cos(furthestAngles.t);
            var radiusReductionBottom = -Math.max(furthestLimits.b - (me.height - me.paddingTop), 0) / Math.cos(furthestAngles.b);

            radiusReductionLeft = numberOrZero(radiusReductionLeft);
            radiusReductionRight = numberOrZero(radiusReductionRight);
            radiusReductionTop = numberOrZero(radiusReductionTop);
            radiusReductionBottom = numberOrZero(radiusReductionBottom);

            me.drawingArea = Math.min(
                Math.floor(largestPossibleRadius - (radiusReductionLeft + radiusReductionRight) / 2),
                Math.floor(largestPossibleRadius - (radiusReductionTop + radiusReductionBottom) / 2));
            me.setCenterPoint(radiusReductionLeft, radiusReductionRight, radiusReductionTop, radiusReductionBottom);
        },

        setCenterPoint: function (leftMovement, rightMovement, topMovement, bottomMovement) {
            var me = this;
            var maxRight = me.width - rightMovement - me.drawingArea;
            var maxLeft = leftMovement + me.drawingArea;
            var maxTop = topMovement + me.drawingArea;
            var maxBottom = (me.height - me.paddingTop) - bottomMovement - me.drawingArea;

            me.xCenter = Math.floor(((maxLeft + maxRight) / 2) + me.left);
            me.yCenter = Math.floor(((maxTop + maxBottom) / 2) + me.top + me.paddingTop);
        },

        getIndexAngle: function (index) {
            var angleMultiplier = (Math.PI * 2) / getValueCount(this);
            var startAngle = this.chart.options && this.chart.options.startAngle ?
                this.chart.options.startAngle :
                0;

            var startAngleRadians = startAngle * Math.PI * 2 / 360;

            // Start from the top instead of right, so remove a quarter of the circle
            return index * angleMultiplier + startAngleRadians;
        },

        getDistanceFromCenterForValue: function (value) {
            var me = this;

            if (value === null) {
                return 0; // null always in center
            }

            // Take into account half font size + the yPadding of the top value
            var scalingFactor = me.drawingArea / (me.max - me.min);
            if (me.options.ticks.reverse) {
                return (me.max - value) * scalingFactor;
            }
            return (value - me.min) * scalingFactor;
        },

        getPointPosition: function (index, distanceFromCenter) {
            var me = this;
            var thisAngle = me.getIndexAngle(index) - (Math.PI / 2);
            return {
                x: Math.cos(thisAngle) * distanceFromCenter + me.xCenter,
                y: Math.sin(thisAngle) * distanceFromCenter + me.yCenter
            };
        },

        getPointPositionForValue: function (index, value) {
            return this.getPointPosition(index, this.getDistanceFromCenterForValue(value));
        },

        getBasePosition: function () {
            var me = this;
            var min = me.min;
            var max = me.max;

            return me.getPointPositionForValue(0,
                me.beginAtZero ? 0 :
                    min < 0 && max < 0 ? max :
                        min > 0 && max > 0 ? min :
                            0);
        },

        draw: function () {
            var me = this;
            var opts = me.options;
            var gridLineOpts = opts.gridLines;
            var tickOpts = opts.ticks;

            if (opts.display) {
                var ctx = me.ctx;
                var startAngle = this.getIndexAngle(0);
                var tickFont = helpers$1.options._parseFont(tickOpts);

                if (opts.angleLines.display || opts.pointLabels.display) {
                    drawPointLabels(me);
                }

                helpers$1.each(me.ticks, function (label, index) {
                    // Don't draw a centre value (if it is minimum)
                    if (index > 0 || tickOpts.reverse) {
                        var yCenterOffset = me.getDistanceFromCenterForValue(me.ticksAsNumbers[index]);

                        // Draw circular lines around the scale
                        if (gridLineOpts.display && index !== 0) {
                            drawRadiusLine(me, gridLineOpts, yCenterOffset, index);
                        }

                        if (tickOpts.display) {
                            var tickFontColor = valueOrDefault$b(tickOpts.fontColor, core_defaults.global.defaultFontColor);
                            ctx.font = tickFont.string;

                            ctx.save();
                            ctx.translate(me.xCenter, me.yCenter);
                            ctx.rotate(startAngle);

                            if (tickOpts.showLabelBackdrop) {
                                var labelWidth = ctx.measureText(label).width;
                                ctx.fillStyle = tickOpts.backdropColor;
                                ctx.fillRect(
                                    -labelWidth / 2 - tickOpts.backdropPaddingX,
                                    -yCenterOffset - tickFont.size / 2 - tickOpts.backdropPaddingY,
                                    labelWidth + tickOpts.backdropPaddingX * 2,
                                    tickFont.size + tickOpts.backdropPaddingY * 2
                                );
                            }

                            ctx.textAlign = 'center';
                            ctx.textBaseline = 'middle';
                            ctx.fillStyle = tickFontColor;
                            ctx.fillText(label, 0, -yCenterOffset);
                            ctx.restore();
                        }
                    }
                });
            }
        }
    });

    // INTERNAL: static default options, registered in src/index.js
    var _defaults$3 = defaultConfig$3;
    scale_radialLinear._defaults = _defaults$3;

    var valueOrDefault$c = helpers$1.valueOrDefault;

    // Integer constants are from the ES6 spec.
    var MIN_INTEGER = Number.MIN_SAFE_INTEGER || -9007199254740991;
    var MAX_INTEGER = Number.MAX_SAFE_INTEGER || 9007199254740991;

    var INTERVALS = {
        millisecond: {
            common: true,
            size: 1,
            steps: [1, 2, 5, 10, 20, 50, 100, 250, 500]
        },
        second: {
            common: true,
            size: 1000,
            steps: [1, 2, 5, 10, 15, 30]
        },
        minute: {
            common: true,
            size: 60000,
            steps: [1, 2, 5, 10, 15, 30]
        },
        hour: {
            common: true,
            size: 3600000,
            steps: [1, 2, 3, 6, 12]
        },
        day: {
            common: true,
            size: 86400000,
            steps: [1, 2, 5]
        },
        week: {
            common: false,
            size: 604800000,
            steps: [1, 2, 3, 4]
        },
        month: {
            common: true,
            size: 2.628e9,
            steps: [1, 2, 3]
        },
        quarter: {
            common: false,
            size: 7.884e9,
            steps: [1, 2, 3, 4]
        },
        year: {
            common: true,
            size: 3.154e10
        }
    };

    var UNITS = Object.keys(INTERVALS);

    function sorter(a, b) {
        return a - b;
    }

    function arrayUnique(items) {
        var hash = {};
        var out = [];
        var i, ilen, item;

        for (i = 0, ilen = items.length; i < ilen; ++i) {
            item = items[i];
            if (!hash[item]) {
                hash[item] = true;
                out.push(item);
            }
        }

        return out;
    }

    /**
     * Returns an array of {time, pos} objects used to interpolate a specific `time` or position
     * (`pos`) on the scale, by searching entries before and after the requested value. `pos` is
     * a decimal between 0 and 1: 0 being the start of the scale (left or top) and 1 the other
     * extremity (left + width or top + height). Note that it would be more optimized to directly
     * store pre-computed pixels, but the scale dimensions are not guaranteed at the time we need
     * to create the lookup table. The table ALWAYS contains at least two items: min and max.
     *
     * @param {number[]} timestamps - timestamps sorted from lowest to highest.
     * @param {string} distribution - If 'linear', timestamps will be spread linearly along the min
     * and max range, so basically, the table will contains only two items: {min, 0} and {max, 1}.
     * If 'series', timestamps will be positioned at the same distance from each other. In this
     * case, only timestamps that break the time linearity are registered, meaning that in the
     * best case, all timestamps are linear, the table contains only min and max.
     */
    function buildLookupTable(timestamps, min, max, distribution) {
        if (distribution === 'linear' || !timestamps.length) {
            return [
                { time: min, pos: 0 },
                { time: max, pos: 1 }
            ];
        }

        var table = [];
        var items = [min];
        var i, ilen, prev, curr, next;

        for (i = 0, ilen = timestamps.length; i < ilen; ++i) {
            curr = timestamps[i];
            if (curr > min && curr < max) {
                items.push(curr);
            }
        }

        items.push(max);

        for (i = 0, ilen = items.length; i < ilen; ++i) {
            next = items[i + 1];
            prev = items[i - 1];
            curr = items[i];

            // only add points that breaks the scale linearity
            if (prev === undefined || next === undefined || Math.round((next + prev) / 2) !== curr) {
                table.push({ time: curr, pos: i / (ilen - 1) });
            }
        }

        return table;
    }

    // @see adapted from https://www.anujgakhar.com/2014/03/01/binary-search-in-javascript/
    function lookup(table, key, value) {
        var lo = 0;
        var hi = table.length - 1;
        var mid, i0, i1;

        while (lo >= 0 && lo <= hi) {
            mid = (lo + hi) >> 1;
            i0 = table[mid - 1] || null;
            i1 = table[mid];

            if (!i0) {
                // given value is outside table (before first item)
                return { lo: null, hi: i1 };
            } else if (i1[key] < value) {
                lo = mid + 1;
            } else if (i0[key] > value) {
                hi = mid - 1;
            } else {
                return { lo: i0, hi: i1 };
            }
        }

        // given value is outside table (after last item)
        return { lo: i1, hi: null };
    }

    /**
     * Linearly interpolates the given source `value` using the table items `skey` values and
     * returns the associated `tkey` value. For example, interpolate(table, 'time', 42, 'pos')
     * returns the position for a timestamp equal to 42. If value is out of bounds, values at
     * index [0, 1] or [n - 1, n] are used for the interpolation.
     */
    function interpolate$1(table, skey, sval, tkey) {
        var range = lookup(table, skey, sval);

        // Note: the lookup table ALWAYS contains at least 2 items (min and max)
        var prev = !range.lo ? table[0] : !range.hi ? table[table.length - 2] : range.lo;
        var next = !range.lo ? table[1] : !range.hi ? table[table.length - 1] : range.hi;

        var span = next[skey] - prev[skey];
        var ratio = span ? (sval - prev[skey]) / span : 0;
        var offset = (next[tkey] - prev[tkey]) * ratio;

        return prev[tkey] + offset;
    }

    function toTimestamp(scale, input) {
        var adapter = scale._adapter;
        var options = scale.options.time;
        var parser = options.parser;
        var format = parser || options.format;
        var value = input;

        if (typeof parser === 'function') {
            value = parser(value);
        }

        // Only parse if its not a timestamp already
        if (!helpers$1.isFinite(value)) {
            value = typeof format === 'string'
                ? adapter.parse(value, format)
                : adapter.parse(value);
        }

        if (value !== null) {
            return +value;
        }

        // Labels are in an incompatible format and no `parser` has been provided.
        // The user might still use the deprecated `format` option for parsing.
        if (!parser && typeof format === 'function') {
            value = format(input);

            // `format` could return something else than a timestamp, if so, parse it
            if (!helpers$1.isFinite(value)) {
                value = adapter.parse(value);
            }
        }

        return value;
    }

    function parse(scale, input) {
        if (helpers$1.isNullOrUndef(input)) {
            return null;
        }

        var options = scale.options.time;
        var value = toTimestamp(scale, scale.getRightValue(input));
        if (value === null) {
            return value;
        }

        if (options.round) {
            value = +scale._adapter.startOf(value, options.round);
        }

        return value;
    }

    /**
     * Returns the number of unit to skip to be able to display up to `capacity` number of ticks
     * in `unit` for the given `min` / `max` range and respecting the interval steps constraints.
     */
    function determineStepSize(min, max, unit, capacity) {
        var range = max - min;
        var interval = INTERVALS[unit];
        var milliseconds = interval.size;
        var steps = interval.steps;
        var i, ilen, factor;

        if (!steps) {
            return Math.ceil(range / (capacity * milliseconds));
        }

        for (i = 0, ilen = steps.length; i < ilen; ++i) {
            factor = steps[i];
            if (Math.ceil(range / (milliseconds * factor)) <= capacity) {
                break;
            }
        }

        return factor;
    }

    /**
     * Figures out what unit results in an appropriate number of auto-generated ticks
     */
    function determineUnitForAutoTicks(minUnit, min, max, capacity) {
        var ilen = UNITS.length;
        var i, interval, factor;

        for (i = UNITS.indexOf(minUnit); i < ilen - 1; ++i) {
            interval = INTERVALS[UNITS[i]];
            factor = interval.steps ? interval.steps[interval.steps.length - 1] : MAX_INTEGER;

            if (interval.common && Math.ceil((max - min) / (factor * interval.size)) <= capacity) {
                return UNITS[i];
            }
        }

        return UNITS[ilen - 1];
    }

    /**
     * Figures out what unit to format a set of ticks with
     */
    function determineUnitForFormatting(scale, ticks, minUnit, min, max) {
        var ilen = UNITS.length;
        var i, unit;

        for (i = ilen - 1; i >= UNITS.indexOf(minUnit); i--) {
            unit = UNITS[i];
            if (INTERVALS[unit].common && scale._adapter.diff(max, min, unit) >= ticks.length) {
                return unit;
            }
        }

        return UNITS[minUnit ? UNITS.indexOf(minUnit) : 0];
    }

    function determineMajorUnit(unit) {
        for (var i = UNITS.indexOf(unit) + 1, ilen = UNITS.length; i < ilen; ++i) {
            if (INTERVALS[UNITS[i]].common) {
                return UNITS[i];
            }
        }
    }

    /**
     * Generates a maximum of `capacity` timestamps between min and max, rounded to the
     * `minor` unit, aligned on the `major` unit and using the given scale time `options`.
     * Important: this method can return ticks outside the min and max range, it's the
     * responsibility of the calling code to clamp values if needed.
     */
    function generate(scale, min, max, capacity) {
        var adapter = scale._adapter;
        var options = scale.options;
        var timeOpts = options.time;
        var minor = timeOpts.unit || determineUnitForAutoTicks(timeOpts.minUnit, min, max, capacity);
        var major = determineMajorUnit(minor);
        var stepSize = valueOrDefault$c(timeOpts.stepSize, timeOpts.unitStepSize);
        var weekday = minor === 'week' ? timeOpts.isoWeekday : false;
        var majorTicksEnabled = options.ticks.major.enabled;
        var interval = INTERVALS[minor];
        var first = min;
        var last = max;
        var ticks = [];
        var time;

        if (!stepSize) {
            stepSize = determineStepSize(min, max, minor, capacity);
        }

        // For 'week' unit, handle the first day of week option
        if (weekday) {
            first = +adapter.startOf(first, 'isoWeek', weekday);
            last = +adapter.startOf(last, 'isoWeek', weekday);
        }

        // Align first/last ticks on unit
        first = +adapter.startOf(first, weekday ? 'day' : minor);
        last = +adapter.startOf(last, weekday ? 'day' : minor);

        // Make sure that the last tick include max
        if (last < max) {
            last = +adapter.add(last, 1, minor);
        }

        time = first;

        if (majorTicksEnabled && major && !weekday && !timeOpts.round) {
            // Align the first tick on the previous `minor` unit aligned on the `major` unit:
            // we first aligned time on the previous `major` unit then add the number of full
            // stepSize there is between first and the previous major time.
            time = +adapter.startOf(time, major);
            time = +adapter.add(time, ~~((first - time) / (interval.size * stepSize)) * stepSize, minor);
        }

        for (; time < last; time = +adapter.add(time, stepSize, minor)) {
            ticks.push(+time);
        }

        ticks.push(+time);

        return ticks;
    }

    /**
     * Returns the start and end offsets from edges in the form of {start, end}
     * where each value is a relative width to the scale and ranges between 0 and 1.
     * They add extra margins on the both sides by scaling down the original scale.
     * Offsets are added when the `offset` option is true.
     */
    function computeOffsets(table, ticks, min, max, options) {
        var start = 0;
        var end = 0;
        var first, last;

        if (options.offset && ticks.length) {
            if (!options.time.min) {
                first = interpolate$1(table, 'time', ticks[0], 'pos');
                if (ticks.length === 1) {
                    start = 1 - first;
                } else {
                    start = (interpolate$1(table, 'time', ticks[1], 'pos') - first) / 2;
                }
            }
            if (!options.time.max) {
                last = interpolate$1(table, 'time', ticks[ticks.length - 1], 'pos');
                if (ticks.length === 1) {
                    end = last;
                } else {
                    end = (last - interpolate$1(table, 'time', ticks[ticks.length - 2], 'pos')) / 2;
                }
            }
        }

        return { start: start, end: end };
    }

    function ticksFromTimestamps(scale, values, majorUnit) {
        var ticks = [];
        var i, ilen, value, major;

        for (i = 0, ilen = values.length; i < ilen; ++i) {
            value = values[i];
            major = majorUnit ? value === +scale._adapter.startOf(value, majorUnit) : false;

            ticks.push({
                value: value,
                major: major
            });
        }

        return ticks;
    }

    var defaultConfig$4 = {
        position: 'bottom',

        /**
         * Data distribution along the scale:
         * - 'linear': data are spread according to their time (distances can vary),
         * - 'series': data are spread at the same distance from each other.
         * @see https://github.com/chartjs/Chart.js/pull/4507
         * @since 2.7.0
         */
        distribution: 'linear',

        /**
         * Scale boundary strategy (bypassed by min/max time options)
         * - `data`: make sure data are fully visible, ticks outside are removed
         * - `ticks`: make sure ticks are fully visible, data outside are truncated
         * @see https://github.com/chartjs/Chart.js/pull/4556
         * @since 2.7.0
         */
        bounds: 'data',

        adapters: {},
        time: {
            parser: false, // false == a pattern string from https://momentjs.com/docs/#/parsing/string-format/ or a custom callback that converts its argument to a moment
            format: false, // DEPRECATED false == date objects, moment object, callback or a pattern string from https://momentjs.com/docs/#/parsing/string-format/
            unit: false, // false == automatic or override with week, month, year, etc.
            round: false, // none, or override with week, month, year, etc.
            displayFormat: false, // DEPRECATED
            isoWeekday: false, // override week start day - see https://momentjs.com/docs/#/get-set/iso-weekday/
            minUnit: 'millisecond',
            displayFormats: {}
        },
        ticks: {
            autoSkip: false,

            /**
             * Ticks generation input values:
             * - 'auto': generates "optimal" ticks based on scale size and time options.
             * - 'data': generates ticks from data (including labels from data {t|x|y} objects).
             * - 'labels': generates ticks from user given `data.labels` values ONLY.
             * @see https://github.com/chartjs/Chart.js/pull/4507
             * @since 2.7.0
             */
            source: 'auto',

            major: {
                enabled: false
            }
        }
    };

    var scale_time = core_scale.extend({
        initialize: function () {
            this.mergeTicksOptions();
            core_scale.prototype.initialize.call(this);
        },

        update: function () {
            var me = this;
            var options = me.options;
            var time = options.time || (options.time = {});
            var adapter = me._adapter = new core_adapters._date(options.adapters.date);

            // DEPRECATIONS: output a message only one time per update
            if (time.format) {
                console.warn('options.time.format is deprecated and replaced by options.time.parser.');
            }

            // Backward compatibility: before introducing adapter, `displayFormats` was
            // supposed to contain *all* unit/string pairs but this can't be resolved
            // when loading the scale (adapters are loaded afterward), so let's populate
            // missing formats on update
            helpers$1.mergeIf(time.displayFormats, adapter.formats());

            return core_scale.prototype.update.apply(me, arguments);
        },

        /**
         * Allows data to be referenced via 't' attribute
         */
        getRightValue: function (rawValue) {
            if (rawValue && rawValue.t !== undefined) {
                rawValue = rawValue.t;
            }
            return core_scale.prototype.getRightValue.call(this, rawValue);
        },

        determineDataLimits: function () {
            var me = this;
            var chart = me.chart;
            var adapter = me._adapter;
            var timeOpts = me.options.time;
            var unit = timeOpts.unit || 'day';
            var min = MAX_INTEGER;
            var max = MIN_INTEGER;
            var timestamps = [];
            var datasets = [];
            var labels = [];
            var i, j, ilen, jlen, data, timestamp;
            var dataLabels = chart.data.labels || [];

            // Convert labels to timestamps
            for (i = 0, ilen = dataLabels.length; i < ilen; ++i) {
                labels.push(parse(me, dataLabels[i]));
            }

            // Convert data to timestamps
            for (i = 0, ilen = (chart.data.datasets || []).length; i < ilen; ++i) {
                if (chart.isDatasetVisible(i)) {
                    data = chart.data.datasets[i].data;

                    // Let's consider that all data have the same format.
                    if (helpers$1.isObject(data[0])) {
                        datasets[i] = [];

                        for (j = 0, jlen = data.length; j < jlen; ++j) {
                            timestamp = parse(me, data[j]);
                            timestamps.push(timestamp);
                            datasets[i][j] = timestamp;
                        }
                    } else {
                        for (j = 0, jlen = labels.length; j < jlen; ++j) {
                            timestamps.push(labels[j]);
                        }
                        datasets[i] = labels.slice(0);
                    }
                } else {
                    datasets[i] = [];
                }
            }

            if (labels.length) {
                // Sort labels **after** data have been converted
                labels = arrayUnique(labels).sort(sorter);
                min = Math.min(min, labels[0]);
                max = Math.max(max, labels[labels.length - 1]);
            }

            if (timestamps.length) {
                timestamps = arrayUnique(timestamps).sort(sorter);
                min = Math.min(min, timestamps[0]);
                max = Math.max(max, timestamps[timestamps.length - 1]);
            }

            min = parse(me, timeOpts.min) || min;
            max = parse(me, timeOpts.max) || max;

            // In case there is no valid min/max, set limits based on unit time option
            min = min === MAX_INTEGER ? +adapter.startOf(Date.now(), unit) : min;
            max = max === MIN_INTEGER ? +adapter.endOf(Date.now(), unit) + 1 : max;

            // Make sure that max is strictly higher than min (required by the lookup table)
            me.min = Math.min(min, max);
            me.max = Math.max(min + 1, max);

            // PRIVATE
            me._horizontal = me.isHorizontal();
            me._table = [];
            me._timestamps = {
                data: timestamps,
                datasets: datasets,
                labels: labels
            };
        },

        buildTicks: function () {
            var me = this;
            var min = me.min;
            var max = me.max;
            var options = me.options;
            var timeOpts = options.time;
            var timestamps = [];
            var ticks = [];
            var i, ilen, timestamp;

            switch (options.ticks.source) {
                case 'data':
                    timestamps = me._timestamps.data;
                    break;
                case 'labels':
                    timestamps = me._timestamps.labels;
                    break;
                case 'auto':
                default:
                    timestamps = generate(me, min, max, me.getLabelCapacity(min), options);
            }

            if (options.bounds === 'ticks' && timestamps.length) {
                min = timestamps[0];
                max = timestamps[timestamps.length - 1];
            }

            // Enforce limits with user min/max options
            min = parse(me, timeOpts.min) || min;
            max = parse(me, timeOpts.max) || max;

            // Remove ticks outside the min/max range
            for (i = 0, ilen = timestamps.length; i < ilen; ++i) {
                timestamp = timestamps[i];
                if (timestamp >= min && timestamp <= max) {
                    ticks.push(timestamp);
                }
            }

            me.min = min;
            me.max = max;

            // PRIVATE
            me._unit = timeOpts.unit || determineUnitForFormatting(me, ticks, timeOpts.minUnit, me.min, me.max);
            me._majorUnit = determineMajorUnit(me._unit);
            me._table = buildLookupTable(me._timestamps.data, min, max, options.distribution);
            me._offsets = computeOffsets(me._table, ticks, min, max, options);

            if (options.ticks.reverse) {
                ticks.reverse();
            }

            return ticksFromTimestamps(me, ticks, me._majorUnit);
        },

        getLabelForIndex: function (index, datasetIndex) {
            var me = this;
            var adapter = me._adapter;
            var data = me.chart.data;
            var timeOpts = me.options.time;
            var label = data.labels && index < data.labels.length ? data.labels[index] : '';
            var value = data.datasets[datasetIndex].data[index];

            if (helpers$1.isObject(value)) {
                label = me.getRightValue(value);
            }
            if (timeOpts.tooltipFormat) {
                return adapter.format(toTimestamp(me, label), timeOpts.tooltipFormat);
            }
            if (typeof label === 'string') {
                return label;
            }
            return adapter.format(toTimestamp(me, label), timeOpts.displayFormats.datetime);
        },

        /**
         * Function to format an individual tick mark
         * @private
         */
        tickFormatFunction: function (time, index, ticks, format) {
            var me = this;
            var adapter = me._adapter;
            var options = me.options;
            var formats = options.time.displayFormats;
            var minorFormat = formats[me._unit];
            var majorUnit = me._majorUnit;
            var majorFormat = formats[majorUnit];
            var majorTime = +adapter.startOf(time, majorUnit);
            var majorTickOpts = options.ticks.major;
            var major = majorTickOpts.enabled && majorUnit && majorFormat && time === majorTime;
            var label = adapter.format(time, format ? format : major ? majorFormat : minorFormat);
            var tickOpts = major ? majorTickOpts : options.ticks.minor;
            var formatter = valueOrDefault$c(tickOpts.callback, tickOpts.userCallback);

            return formatter ? formatter(label, index, ticks) : label;
        },

        convertTicksToLabels: function (ticks) {
            var labels = [];
            var i, ilen;

            for (i = 0, ilen = ticks.length; i < ilen; ++i) {
                labels.push(this.tickFormatFunction(ticks[i].value, i, ticks));
            }

            return labels;
        },

        /**
         * @private
         */
        getPixelForOffset: function (time) {
            var me = this;
            var isReverse = me.options.ticks.reverse;
            var size = me._horizontal ? me.width : me.height;
            var start = me._horizontal ? isReverse ? me.right : me.left : isReverse ? me.bottom : me.top;
            var pos = interpolate$1(me._table, 'time', time, 'pos');
            var offset = size * (me._offsets.start + pos) / (me._offsets.start + 1 + me._offsets.end);

            return isReverse ? start - offset : start + offset;
        },

        getPixelForValue: function (value, index, datasetIndex) {
            var me = this;
            var time = null;

            if (index !== undefined && datasetIndex !== undefined) {
                time = me._timestamps.datasets[datasetIndex][index];
            }

            if (time === null) {
                time = parse(me, value);
            }

            if (time !== null) {
                return me.getPixelForOffset(time);
            }
        },

        getPixelForTick: function (index) {
            var ticks = this.getTicks();
            return index >= 0 && index < ticks.length ?
                this.getPixelForOffset(ticks[index].value) :
                null;
        },

        getValueForPixel: function (pixel) {
            var me = this;
            var size = me._horizontal ? me.width : me.height;
            var start = me._horizontal ? me.left : me.top;
            var pos = (size ? (pixel - start) / size : 0) * (me._offsets.start + 1 + me._offsets.start) - me._offsets.end;
            var time = interpolate$1(me._table, 'pos', pos, 'time');

            // DEPRECATION, we should return time directly
            return me._adapter._create(time);
        },

        /**
         * Crude approximation of what the label width might be
         * @private
         */
        getLabelWidth: function (label) {
            var me = this;
            var ticksOpts = me.options.ticks;
            var tickLabelWidth = me.ctx.measureText(label).width;
            var angle = helpers$1.toRadians(ticksOpts.maxRotation);
            var cosRotation = Math.cos(angle);
            var sinRotation = Math.sin(angle);
            var tickFontSize = valueOrDefault$c(ticksOpts.fontSize, core_defaults.global.defaultFontSize);

            return (tickLabelWidth * cosRotation) + (tickFontSize * sinRotation);
        },

        /**
         * @private
         */
        getLabelCapacity: function (exampleTime) {
            var me = this;

            // pick the longest format (milliseconds) for guestimation
            var format = me.options.time.displayFormats.millisecond;
            var exampleLabel = me.tickFormatFunction(exampleTime, 0, [], format);
            var tickLabelWidth = me.getLabelWidth(exampleLabel);
            var innerWidth = me.isHorizontal() ? me.width : me.height;
            var capacity = Math.floor(innerWidth / tickLabelWidth);

            return capacity > 0 ? capacity : 1;
        }
    });

    // INTERNAL: static default options, registered in src/index.js
    var _defaults$4 = defaultConfig$4;
    scale_time._defaults = _defaults$4;

    var scales = {
        category: scale_category,
        linear: scale_linear,
        logarithmic: scale_logarithmic,
        radialLinear: scale_radialLinear,
        time: scale_time
    };

    var FORMATS = {
        datetime: 'MMM D, YYYY, h:mm:ss a',
        millisecond: 'h:mm:ss.SSS a',
        second: 'h:mm:ss a',
        minute: 'h:mm a',
        hour: 'hA',
        day: 'MMM D',
        week: 'll',
        month: 'MMM YYYY',
        quarter: '[Q]Q - YYYY',
        year: 'YYYY'
    };

    core_adapters._date.override(typeof moment === 'function' ? {
        _id: 'moment', // DEBUG ONLY

        formats: function () {
            return FORMATS;
        },

        parse: function (value, format) {
            if (typeof value === 'string' && typeof format === 'string') {
                value = moment(value, format);
            } else if (!(value instanceof moment)) {
                value = moment(value);
            }
            return value.isValid() ? value.valueOf() : null;
        },

        format: function (time, format) {
            return moment(time).format(format);
        },

        add: function (time, amount, unit) {
            return moment(time).add(amount, unit).valueOf();
        },

        diff: function (max, min, unit) {
            return moment.duration(moment(max).diff(moment(min))).as(unit);
        },

        startOf: function (time, unit, weekday) {
            time = moment(time);
            if (unit === 'isoWeek') {
                return time.isoWeekday(weekday).valueOf();
            }
            return time.startOf(unit).valueOf();
        },

        endOf: function (time, unit) {
            return moment(time).endOf(unit).valueOf();
        },

        // DEPRECATIONS

        /**
         * Provided for backward compatibility with scale.getValueForPixel().
         * @deprecated since version 2.8.0
         * @todo remove at version 3
         * @private
         */
        _create: function (time) {
            return moment(time);
        },
    } : {});

    core_defaults._set('global', {
        plugins: {
            filler: {
                propagate: true
            }
        }
    });

    var mappers = {
        dataset: function (source) {
            var index = source.fill;
            var chart = source.chart;
            var meta = chart.getDatasetMeta(index);
            var visible = meta && chart.isDatasetVisible(index);
            var points = (visible && meta.dataset._children) || [];
            var length = points.length || 0;

            return !length ? null : function (point, i) {
                return (i < length && points[i]._view) || null;
            };
        },

        boundary: function (source) {
            var boundary = source.boundary;
            var x = boundary ? boundary.x : null;
            var y = boundary ? boundary.y : null;

            return function (point) {
                return {
                    x: x === null ? point.x : x,
                    y: y === null ? point.y : y,
                };
            };
        }
    };

    // @todo if (fill[0] === '#')
    function decodeFill(el, index, count) {
        var model = el._model || {};
        var fill = model.fill;
        var target;

        if (fill === undefined) {
            fill = !!model.backgroundColor;
        }

        if (fill === false || fill === null) {
            return false;
        }

        if (fill === true) {
            return 'origin';
        }

        target = parseFloat(fill, 10);
        if (isFinite(target) && Math.floor(target) === target) {
            if (fill[0] === '-' || fill[0] === '+') {
                target = index + target;
            }

            if (target === index || target < 0 || target >= count) {
                return false;
            }

            return target;
        }

        switch (fill) {
            // compatibility
            case 'bottom':
                return 'start';
            case 'top':
                return 'end';
            case 'zero':
                return 'origin';
            // supported boundaries
            case 'origin':
            case 'start':
            case 'end':
                return fill;
            // invalid fill values
            default:
                return false;
        }
    }

    function computeBoundary(source) {
        var model = source.el._model || {};
        var scale = source.el._scale || {};
        var fill = source.fill;
        var target = null;
        var horizontal;

        if (isFinite(fill)) {
            return null;
        }

        // Backward compatibility: until v3, we still need to support boundary values set on
        // the model (scaleTop, scaleBottom and scaleZero) because some external plugins and
        // controllers might still use it (e.g. the Smith chart).

        if (fill === 'start') {
            target = model.scaleBottom === undefined ? scale.bottom : model.scaleBottom;
        } else if (fill === 'end') {
            target = model.scaleTop === undefined ? scale.top : model.scaleTop;
        } else if (model.scaleZero !== undefined) {
            target = model.scaleZero;
        } else if (scale.getBasePosition) {
            target = scale.getBasePosition();
        } else if (scale.getBasePixel) {
            target = scale.getBasePixel();
        }

        if (target !== undefined && target !== null) {
            if (target.x !== undefined && target.y !== undefined) {
                return target;
            }

            if (helpers$1.isFinite(target)) {
                horizontal = scale.isHorizontal();
                return {
                    x: horizontal ? target : null,
                    y: horizontal ? null : target
                };
            }
        }

        return null;
    }

    function resolveTarget(sources, index, propagate) {
        var source = sources[index];
        var fill = source.fill;
        var visited = [index];
        var target;

        if (!propagate) {
            return fill;
        }

        while (fill !== false && visited.indexOf(fill) === -1) {
            if (!isFinite(fill)) {
                return fill;
            }

            target = sources[fill];
            if (!target) {
                return false;
            }

            if (target.visible) {
                return fill;
            }

            visited.push(fill);
            fill = target.fill;
        }

        return false;
    }

    function createMapper(source) {
        var fill = source.fill;
        var type = 'dataset';

        if (fill === false) {
            return null;
        }

        if (!isFinite(fill)) {
            type = 'boundary';
        }

        return mappers[type](source);
    }

    function isDrawable(point) {
        return point && !point.skip;
    }

    function drawArea(ctx, curve0, curve1, len0, len1) {
        var i;

        if (!len0 || !len1) {
            return;
        }

        // building first area curve (normal)
        ctx.moveTo(curve0[0].x, curve0[0].y);
        for (i = 1; i < len0; ++i) {
            helpers$1.canvas.lineTo(ctx, curve0[i - 1], curve0[i]);
        }

        // joining the two area curves
        ctx.lineTo(curve1[len1 - 1].x, curve1[len1 - 1].y);

        // building opposite area curve (reverse)
        for (i = len1 - 1; i > 0; --i) {
            helpers$1.canvas.lineTo(ctx, curve1[i], curve1[i - 1], true);
        }
    }

    function doFill(ctx, points, mapper, view, color, loop) {
        var count = points.length;
        var span = view.spanGaps;
        var curve0 = [];
        var curve1 = [];
        var len0 = 0;
        var len1 = 0;
        var i, ilen, index, p0, p1, d0, d1;

        ctx.beginPath();

        for (i = 0, ilen = (count + !!loop); i < ilen; ++i) {
            index = i % count;
            p0 = points[index]._view;
            p1 = mapper(p0, index, view);
            d0 = isDrawable(p0);
            d1 = isDrawable(p1);

            if (d0 && d1) {
                len0 = curve0.push(p0);
                len1 = curve1.push(p1);
            } else if (len0 && len1) {
                if (!span) {
                    drawArea(ctx, curve0, curve1, len0, len1);
                    len0 = len1 = 0;
                    curve0 = [];
                    curve1 = [];
                } else {
                    if (d0) {
                        curve0.push(p0);
                    }
                    if (d1) {
                        curve1.push(p1);
                    }
                }
            }
        }

        drawArea(ctx, curve0, curve1, len0, len1);

        ctx.closePath();
        ctx.fillStyle = color;
        ctx.fill();
    }

    var plugin_filler = {
        id: 'filler',

        afterDatasetsUpdate: function (chart, options) {
            var count = (chart.data.datasets || []).length;
            var propagate = options.propagate;
            var sources = [];
            var meta, i, el, source;

            for (i = 0; i < count; ++i) {
                meta = chart.getDatasetMeta(i);
                el = meta.dataset;
                source = null;

                if (el && el._model && el instanceof elements.Line) {
                    source = {
                        visible: chart.isDatasetVisible(i),
                        fill: decodeFill(el, i, count),
                        chart: chart,
                        el: el
                    };
                }

                meta.$filler = source;
                sources.push(source);
            }

            for (i = 0; i < count; ++i) {
                source = sources[i];
                if (!source) {
                    continue;
                }

                source.fill = resolveTarget(sources, i, propagate);
                source.boundary = computeBoundary(source);
                source.mapper = createMapper(source);
            }
        },

        beforeDatasetDraw: function (chart, args) {
            var meta = args.meta.$filler;
            if (!meta) {
                return;
            }

            var ctx = chart.ctx;
            var el = meta.el;
            var view = el._view;
            var points = el._children || [];
            var mapper = meta.mapper;
            var color = view.backgroundColor || core_defaults.global.defaultColor;

            if (mapper && color && points.length) {
                helpers$1.canvas.clipArea(ctx, chart.chartArea);
                doFill(ctx, points, mapper, view, color, el._loop);
                helpers$1.canvas.unclipArea(ctx);
            }
        }
    };

    var noop$1 = helpers$1.noop;
    var valueOrDefault$d = helpers$1.valueOrDefault;

    core_defaults._set('global', {
        legend: {
            display: true,
            position: 'top',
            fullWidth: true,
            reverse: false,
            weight: 1000,

            // a callback that will handle
            onClick: function (e, legendItem) {
                var index = legendItem.datasetIndex;
                var ci = this.chart;
                var meta = ci.getDatasetMeta(index);

                // See controller.isDatasetVisible comment
                meta.hidden = meta.hidden === null ? !ci.data.datasets[index].hidden : null;

                // We hid a dataset ... rerender the chart
                ci.update();
            },

            onHover: null,
            onLeave: null,

            labels: {
                boxWidth: 40,
                padding: 10,
                // Generates labels shown in the legend
                // Valid properties to return:
                // text : text to display
                // fillStyle : fill of coloured box
                // strokeStyle: stroke of coloured box
                // hidden : if this legend item refers to a hidden item
                // lineCap : cap style for line
                // lineDash
                // lineDashOffset :
                // lineJoin :
                // lineWidth :
                generateLabels: function (chart) {
                    var data = chart.data;
                    return helpers$1.isArray(data.datasets) ? data.datasets.map(function (dataset, i) {
                        return {
                            text: dataset.label,
                            fillStyle: (!helpers$1.isArray(dataset.backgroundColor) ? dataset.backgroundColor : dataset.backgroundColor[0]),
                            hidden: !chart.isDatasetVisible(i),
                            lineCap: dataset.borderCapStyle,
                            lineDash: dataset.borderDash,
                            lineDashOffset: dataset.borderDashOffset,
                            lineJoin: dataset.borderJoinStyle,
                            lineWidth: dataset.borderWidth,
                            strokeStyle: dataset.borderColor,
                            pointStyle: dataset.pointStyle,

                            // Below is extra data used for toggling the datasets
                            datasetIndex: i
                        };
                    }, this) : [];
                }
            }
        },

        legendCallback: function (chart) {
            var text = [];
            text.push('<ul class="' + chart.id + '-legend">');
            for (var i = 0; i < chart.data.datasets.length; i++) {
                text.push('<li><span style="background-color:' + chart.data.datasets[i].backgroundColor + '"></span>');
                if (chart.data.datasets[i].label) {
                    text.push(chart.data.datasets[i].label);
                }
                text.push('</li>');
            }
            text.push('</ul>');
            return text.join('');
        }
    });

    /**
     * Helper function to get the box width based on the usePointStyle option
     * @param {object} labelopts - the label options on the legend
     * @param {number} fontSize - the label font size
     * @return {number} width of the color box area
     */
    function getBoxWidth(labelOpts, fontSize) {
        return labelOpts.usePointStyle && labelOpts.boxWidth > fontSize ?
            fontSize :
            labelOpts.boxWidth;
    }

    /**
     * IMPORTANT: this class is exposed publicly as Chart.Legend, backward compatibility required!
     */
    var Legend = core_element.extend({

        initialize: function (config) {
            helpers$1.extend(this, config);

            // Contains hit boxes for each dataset (in dataset order)
            this.legendHitBoxes = [];

            /**
                 * @private
                 */
            this._hoveredItem = null;

            // Are we in doughnut mode which has a different data type
            this.doughnutMode = false;
        },

        // These methods are ordered by lifecycle. Utilities then follow.
        // Any function defined here is inherited by all legend types.
        // Any function can be extended by the legend type

        beforeUpdate: noop$1,
        update: function (maxWidth, maxHeight, margins) {
            var me = this;

            // Update Lifecycle - Probably don't want to ever extend or overwrite this function ;)
            me.beforeUpdate();

            // Absorb the master measurements
            me.maxWidth = maxWidth;
            me.maxHeight = maxHeight;
            me.margins = margins;

            // Dimensions
            me.beforeSetDimensions();
            me.setDimensions();
            me.afterSetDimensions();
            // Labels
            me.beforeBuildLabels();
            me.buildLabels();
            me.afterBuildLabels();

            // Fit
            me.beforeFit();
            me.fit();
            me.afterFit();
            //
            me.afterUpdate();

            return me.minSize;
        },
        afterUpdate: noop$1,

        //

        beforeSetDimensions: noop$1,
        setDimensions: function () {
            var me = this;
            // Set the unconstrained dimension before label rotation
            if (me.isHorizontal()) {
                // Reset position before calculating rotation
                me.width = me.maxWidth;
                me.left = 0;
                me.right = me.width;
            } else {
                me.height = me.maxHeight;

                // Reset position before calculating rotation
                me.top = 0;
                me.bottom = me.height;
            }

            // Reset padding
            me.paddingLeft = 0;
            me.paddingTop = 0;
            me.paddingRight = 0;
            me.paddingBottom = 0;

            // Reset minSize
            me.minSize = {
                width: 0,
                height: 0
            };
        },
        afterSetDimensions: noop$1,

        //

        beforeBuildLabels: noop$1,
        buildLabels: function () {
            var me = this;
            var labelOpts = me.options.labels || {};
            var legendItems = helpers$1.callback(labelOpts.generateLabels, [me.chart], me) || [];

            if (labelOpts.filter) {
                legendItems = legendItems.filter(function (item) {
                    return labelOpts.filter(item, me.chart.data);
                });
            }

            if (me.options.reverse) {
                legendItems.reverse();
            }

            me.legendItems = legendItems;
        },
        afterBuildLabels: noop$1,

        //

        beforeFit: noop$1,
        fit: function () {
            var me = this;
            var opts = me.options;
            var labelOpts = opts.labels;
            var display = opts.display;

            var ctx = me.ctx;

            var labelFont = helpers$1.options._parseFont(labelOpts);
            var fontSize = labelFont.size;

            // Reset hit boxes
            var hitboxes = me.legendHitBoxes = [];

            var minSize = me.minSize;
            var isHorizontal = me.isHorizontal();

            if (isHorizontal) {
                minSize.width = me.maxWidth; // fill all the width
                minSize.height = display ? 10 : 0;
            } else {
                minSize.width = display ? 10 : 0;
                minSize.height = me.maxHeight; // fill all the height
            }

            // Increase sizes here
            if (display) {
                ctx.font = labelFont.string;

                if (isHorizontal) {
                    // Labels

                    // Width of each line of legend boxes. Labels wrap onto multiple lines when there are too many to fit on one
                    var lineWidths = me.lineWidths = [0];
                    var totalHeight = 0;

                    ctx.textAlign = 'left';
                    ctx.textBaseline = 'top';

                    helpers$1.each(me.legendItems, function (legendItem, i) {
                        var boxWidth = getBoxWidth(labelOpts, fontSize);
                        var width = boxWidth + (fontSize / 2) + ctx.measureText(legendItem.text).width;

                        if (i === 0 || lineWidths[lineWidths.length - 1] + width + labelOpts.padding > minSize.width) {
                            totalHeight += fontSize + labelOpts.padding;
                            lineWidths[lineWidths.length - (i > 0 ? 0 : 1)] = labelOpts.padding;
                        }

                        // Store the hitbox width and height here. Final position will be updated in `draw`
                        hitboxes[i] = {
                            left: 0,
                            top: 0,
                            width: width,
                            height: fontSize
                        };

                        lineWidths[lineWidths.length - 1] += width + labelOpts.padding;
                    });

                    minSize.height += totalHeight;

                } else {
                    var vPadding = labelOpts.padding;
                    var columnWidths = me.columnWidths = [];
                    var totalWidth = labelOpts.padding;
                    var currentColWidth = 0;
                    var currentColHeight = 0;
                    var itemHeight = fontSize + vPadding;

                    helpers$1.each(me.legendItems, function (legendItem, i) {
                        var boxWidth = getBoxWidth(labelOpts, fontSize);
                        var itemWidth = boxWidth + (fontSize / 2) + ctx.measureText(legendItem.text).width;

                        // If too tall, go to new column
                        if (i > 0 && currentColHeight + itemHeight > minSize.height - vPadding) {
                            totalWidth += currentColWidth + labelOpts.padding;
                            columnWidths.push(currentColWidth); // previous column width

                            currentColWidth = 0;
                            currentColHeight = 0;
                        }

                        // Get max width
                        currentColWidth = Math.max(currentColWidth, itemWidth);
                        currentColHeight += itemHeight;

                        // Store the hitbox width and height here. Final position will be updated in `draw`
                        hitboxes[i] = {
                            left: 0,
                            top: 0,
                            width: itemWidth,
                            height: fontSize
                        };
                    });

                    totalWidth += currentColWidth;
                    columnWidths.push(currentColWidth);
                    minSize.width += totalWidth;
                }
            }

            me.width = minSize.width;
            me.height = minSize.height;
        },
        afterFit: noop$1,

        // Shared Methods
        isHorizontal: function () {
            return this.options.position === 'top' || this.options.position === 'bottom';
        },

        // Actually draw the legend on the canvas
        draw: function () {
            var me = this;
            var opts = me.options;
            var labelOpts = opts.labels;
            var globalDefaults = core_defaults.global;
            var defaultColor = globalDefaults.defaultColor;
            var lineDefault = globalDefaults.elements.line;
            var legendWidth = me.width;
            var lineWidths = me.lineWidths;

            if (opts.display) {
                var ctx = me.ctx;
                var fontColor = valueOrDefault$d(labelOpts.fontColor, globalDefaults.defaultFontColor);
                var labelFont = helpers$1.options._parseFont(labelOpts);
                var fontSize = labelFont.size;
                var cursor;

                // Canvas setup
                ctx.textAlign = 'left';
                ctx.textBaseline = 'middle';
                ctx.lineWidth = 0.5;
                ctx.strokeStyle = fontColor; // for strikethrough effect
                ctx.fillStyle = fontColor; // render in correct colour
                ctx.font = labelFont.string;

                var boxWidth = getBoxWidth(labelOpts, fontSize);
                var hitboxes = me.legendHitBoxes;

                // current position
                var drawLegendBox = function (x, y, legendItem) {
                    if (isNaN(boxWidth) || boxWidth <= 0) {
                        return;
                    }

                    // Set the ctx for the box
                    ctx.save();

                    var lineWidth = valueOrDefault$d(legendItem.lineWidth, lineDefault.borderWidth);
                    ctx.fillStyle = valueOrDefault$d(legendItem.fillStyle, defaultColor);
                    ctx.lineCap = valueOrDefault$d(legendItem.lineCap, lineDefault.borderCapStyle);
                    ctx.lineDashOffset = valueOrDefault$d(legendItem.lineDashOffset, lineDefault.borderDashOffset);
                    ctx.lineJoin = valueOrDefault$d(legendItem.lineJoin, lineDefault.borderJoinStyle);
                    ctx.lineWidth = lineWidth;
                    ctx.strokeStyle = valueOrDefault$d(legendItem.strokeStyle, defaultColor);

                    if (ctx.setLineDash) {
                        // IE 9 and 10 do not support line dash
                        ctx.setLineDash(valueOrDefault$d(legendItem.lineDash, lineDefault.borderDash));
                    }

                    if (opts.labels && opts.labels.usePointStyle) {
                        // Recalculate x and y for drawPoint() because its expecting
                        // x and y to be center of figure (instead of top left)
                        var radius = boxWidth * Math.SQRT2 / 2;
                        var centerX = x + boxWidth / 2;
                        var centerY = y + fontSize / 2;

                        // Draw pointStyle as legend symbol
                        helpers$1.canvas.drawPoint(ctx, legendItem.pointStyle, radius, centerX, centerY);
                    } else {
                        // Draw box as legend symbol
                        if (lineWidth !== 0) {
                            ctx.strokeRect(x, y, boxWidth, fontSize);
                        }
                        ctx.fillRect(x, y, boxWidth, fontSize);
                    }

                    ctx.restore();
                };
                var fillText = function (x, y, legendItem, textWidth) {
                    var halfFontSize = fontSize / 2;
                    var xLeft = boxWidth + halfFontSize + x;
                    var yMiddle = y + halfFontSize;

                    ctx.fillText(legendItem.text, xLeft, yMiddle);

                    if (legendItem.hidden) {
                        // Strikethrough the text if hidden
                        ctx.beginPath();
                        ctx.lineWidth = 2;
                        ctx.moveTo(xLeft, yMiddle);
                        ctx.lineTo(xLeft + textWidth, yMiddle);
                        ctx.stroke();
                    }
                };

                // Horizontal
                var isHorizontal = me.isHorizontal();
                if (isHorizontal) {
                    cursor = {
                        x: me.left + ((legendWidth - lineWidths[0]) / 2) + labelOpts.padding,
                        y: me.top + labelOpts.padding,
                        line: 0
                    };
                } else {
                    cursor = {
                        x: me.left + labelOpts.padding,
                        y: me.top + labelOpts.padding,
                        line: 0
                    };
                }

                var itemHeight = fontSize + labelOpts.padding;
                helpers$1.each(me.legendItems, function (legendItem, i) {
                    var textWidth = ctx.measureText(legendItem.text).width;
                    var width = boxWidth + (fontSize / 2) + textWidth;
                    var x = cursor.x;
                    var y = cursor.y;

                    // Use (me.left + me.minSize.width) and (me.top + me.minSize.height)
                    // instead of me.right and me.bottom because me.width and me.height
                    // may have been changed since me.minSize was calculated
                    if (isHorizontal) {
                        if (i > 0 && x + width + labelOpts.padding > me.left + me.minSize.width) {
                            y = cursor.y += itemHeight;
                            cursor.line++;
                            x = cursor.x = me.left + ((legendWidth - lineWidths[cursor.line]) / 2) + labelOpts.padding;
                        }
                    } else if (i > 0 && y + itemHeight > me.top + me.minSize.height) {
                        x = cursor.x = x + me.columnWidths[cursor.line] + labelOpts.padding;
                        y = cursor.y = me.top + labelOpts.padding;
                        cursor.line++;
                    }

                    drawLegendBox(x, y, legendItem);

                    hitboxes[i].left = x;
                    hitboxes[i].top = y;

                    // Fill the actual label
                    fillText(x, y, legendItem, textWidth);

                    if (isHorizontal) {
                        cursor.x += width + labelOpts.padding;
                    } else {
                        cursor.y += itemHeight;
                    }

                });
            }
        },

        /**
         * @private
         */
        _getLegendItemAt: function (x, y) {
            var me = this;
            var i, hitBox, lh;

            if (x >= me.left && x <= me.right && y >= me.top && y <= me.bottom) {
                // See if we are touching one of the dataset boxes
                lh = me.legendHitBoxes;
                for (i = 0; i < lh.length; ++i) {
                    hitBox = lh[i];

                    if (x >= hitBox.left && x <= hitBox.left + hitBox.width && y >= hitBox.top && y <= hitBox.top + hitBox.height) {
                        // Touching an element
                        return me.legendItems[i];
                    }
                }
            }

            return null;
        },

        /**
         * Handle an event
         * @private
         * @param {IEvent} event - The event to handle
         */
        handleEvent: function (e) {
            var me = this;
            var opts = me.options;
            var type = e.type === 'mouseup' ? 'click' : e.type;
            var hoveredItem;

            if (type === 'mousemove') {
                if (!opts.onHover && !opts.onLeave) {
                    return;
                }
            } else if (type === 'click') {
                if (!opts.onClick) {
                    return;
                }
            } else {
                return;
            }

            // Chart event already has relative position in it
            hoveredItem = me._getLegendItemAt(e.x, e.y);

            if (type === 'click') {
                if (hoveredItem && opts.onClick) {
                    // use e.native for backwards compatibility
                    opts.onClick.call(me, e.native, hoveredItem);
                }
            } else {
                if (opts.onLeave && hoveredItem !== me._hoveredItem) {
                    if (me._hoveredItem) {
                        opts.onLeave.call(me, e.native, me._hoveredItem);
                    }
                    me._hoveredItem = hoveredItem;
                }

                if (opts.onHover && hoveredItem) {
                    // use e.native for backwards compatibility
                    opts.onHover.call(me, e.native, hoveredItem);
                }
            }
        }
    });

    function createNewLegendAndAttach(chart, legendOpts) {
        var legend = new Legend({
            ctx: chart.ctx,
            options: legendOpts,
            chart: chart
        });

        core_layouts.configure(chart, legend, legendOpts);
        core_layouts.addBox(chart, legend);
        chart.legend = legend;
    }

    var plugin_legend = {
        id: 'legend',

        /**
         * Backward compatibility: since 2.1.5, the legend is registered as a plugin, making
         * Chart.Legend obsolete. To avoid a breaking change, we export the Legend as part of
         * the plugin, which one will be re-exposed in the chart.js file.
         * https://github.com/chartjs/Chart.js/pull/2640
         * @private
         */
        _element: Legend,

        beforeInit: function (chart) {
            var legendOpts = chart.options.legend;

            if (legendOpts) {
                createNewLegendAndAttach(chart, legendOpts);
            }
        },

        beforeUpdate: function (chart) {
            var legendOpts = chart.options.legend;
            var legend = chart.legend;

            if (legendOpts) {
                helpers$1.mergeIf(legendOpts, core_defaults.global.legend);

                if (legend) {
                    core_layouts.configure(chart, legend, legendOpts);
                    legend.options = legendOpts;
                } else {
                    createNewLegendAndAttach(chart, legendOpts);
                }
            } else if (legend) {
                core_layouts.removeBox(chart, legend);
                delete chart.legend;
            }
        },

        afterEvent: function (chart, e) {
            var legend = chart.legend;
            if (legend) {
                legend.handleEvent(e);
            }
        }
    };

    var noop$2 = helpers$1.noop;

    core_defaults._set('global', {
        title: {
            display: false,
            fontStyle: 'bold',
            fullWidth: true,
            padding: 10,
            position: 'top',
            text: '',
            weight: 2000         // by default greater than legend (1000) to be above
        }
    });

    /**
     * IMPORTANT: this class is exposed publicly as Chart.Legend, backward compatibility required!
     */
    var Title = core_element.extend({
        initialize: function (config) {
            var me = this;
            helpers$1.extend(me, config);

            // Contains hit boxes for each dataset (in dataset order)
            me.legendHitBoxes = [];
        },

        // These methods are ordered by lifecycle. Utilities then follow.

        beforeUpdate: noop$2,
        update: function (maxWidth, maxHeight, margins) {
            var me = this;

            // Update Lifecycle - Probably don't want to ever extend or overwrite this function ;)
            me.beforeUpdate();

            // Absorb the master measurements
            me.maxWidth = maxWidth;
            me.maxHeight = maxHeight;
            me.margins = margins;

            // Dimensions
            me.beforeSetDimensions();
            me.setDimensions();
            me.afterSetDimensions();
            // Labels
            me.beforeBuildLabels();
            me.buildLabels();
            me.afterBuildLabels();

            // Fit
            me.beforeFit();
            me.fit();
            me.afterFit();
            //
            me.afterUpdate();

            return me.minSize;

        },
        afterUpdate: noop$2,

        //

        beforeSetDimensions: noop$2,
        setDimensions: function () {
            var me = this;
            // Set the unconstrained dimension before label rotation
            if (me.isHorizontal()) {
                // Reset position before calculating rotation
                me.width = me.maxWidth;
                me.left = 0;
                me.right = me.width;
            } else {
                me.height = me.maxHeight;

                // Reset position before calculating rotation
                me.top = 0;
                me.bottom = me.height;
            }

            // Reset padding
            me.paddingLeft = 0;
            me.paddingTop = 0;
            me.paddingRight = 0;
            me.paddingBottom = 0;

            // Reset minSize
            me.minSize = {
                width: 0,
                height: 0
            };
        },
        afterSetDimensions: noop$2,

        //

        beforeBuildLabels: noop$2,
        buildLabels: noop$2,
        afterBuildLabels: noop$2,

        //

        beforeFit: noop$2,
        fit: function () {
            var me = this;
            var opts = me.options;
            var display = opts.display;
            var minSize = me.minSize;
            var lineCount = helpers$1.isArray(opts.text) ? opts.text.length : 1;
            var fontOpts = helpers$1.options._parseFont(opts);
            var textSize = display ? (lineCount * fontOpts.lineHeight) + (opts.padding * 2) : 0;

            if (me.isHorizontal()) {
                minSize.width = me.maxWidth; // fill all the width
                minSize.height = textSize;
            } else {
                minSize.width = textSize;
                minSize.height = me.maxHeight; // fill all the height
            }

            me.width = minSize.width;
            me.height = minSize.height;

        },
        afterFit: noop$2,

        // Shared Methods
        isHorizontal: function () {
            var pos = this.options.position;
            return pos === 'top' || pos === 'bottom';
        },

        // Actually draw the title block on the canvas
        draw: function () {
            var me = this;
            var ctx = me.ctx;
            var opts = me.options;

            if (opts.display) {
                var fontOpts = helpers$1.options._parseFont(opts);
                var lineHeight = fontOpts.lineHeight;
                var offset = lineHeight / 2 + opts.padding;
                var rotation = 0;
                var top = me.top;
                var left = me.left;
                var bottom = me.bottom;
                var right = me.right;
                var maxWidth, titleX, titleY;

                ctx.fillStyle = helpers$1.valueOrDefault(opts.fontColor, core_defaults.global.defaultFontColor); // render in correct colour
                ctx.font = fontOpts.string;

                // Horizontal
                if (me.isHorizontal()) {
                    titleX = left + ((right - left) / 2); // midpoint of the width
                    titleY = top + offset;
                    maxWidth = right - left;
                } else {
                    titleX = opts.position === 'left' ? left + offset : right - offset;
                    titleY = top + ((bottom - top) / 2);
                    maxWidth = bottom - top;
                    rotation = Math.PI * (opts.position === 'left' ? -0.5 : 0.5);
                }

                ctx.save();
                ctx.translate(titleX, titleY);
                ctx.rotate(rotation);
                ctx.textAlign = 'center';
                ctx.textBaseline = 'middle';

                var text = opts.text;
                if (helpers$1.isArray(text)) {
                    var y = 0;
                    for (var i = 0; i < text.length; ++i) {
                        ctx.fillText(text[i], 0, y, maxWidth);
                        y += lineHeight;
                    }
                } else {
                    ctx.fillText(text, 0, 0, maxWidth);
                }

                ctx.restore();
            }
        }
    });

    function createNewTitleBlockAndAttach(chart, titleOpts) {
        var title = new Title({
            ctx: chart.ctx,
            options: titleOpts,
            chart: chart
        });

        core_layouts.configure(chart, title, titleOpts);
        core_layouts.addBox(chart, title);
        chart.titleBlock = title;
    }

    var plugin_title = {
        id: 'title',

        /**
         * Backward compatibility: since 2.1.5, the title is registered as a plugin, making
         * Chart.Title obsolete. To avoid a breaking change, we export the Title as part of
         * the plugin, which one will be re-exposed in the chart.js file.
         * https://github.com/chartjs/Chart.js/pull/2640
         * @private
         */
        _element: Title,

        beforeInit: function (chart) {
            var titleOpts = chart.options.title;

            if (titleOpts) {
                createNewTitleBlockAndAttach(chart, titleOpts);
            }
        },

        beforeUpdate: function (chart) {
            var titleOpts = chart.options.title;
            var titleBlock = chart.titleBlock;

            if (titleOpts) {
                helpers$1.mergeIf(titleOpts, core_defaults.global.title);

                if (titleBlock) {
                    core_layouts.configure(chart, titleBlock, titleOpts);
                    titleBlock.options = titleOpts;
                } else {
                    createNewTitleBlockAndAttach(chart, titleOpts);
                }
            } else if (titleBlock) {
                core_layouts.removeBox(chart, titleBlock);
                delete chart.titleBlock;
            }
        }
    };

    var plugins = {};
    var filler = plugin_filler;
    var legend = plugin_legend;
    var title = plugin_title;
    plugins.filler = filler;
    plugins.legend = legend;
    plugins.title = title;

    /**
     * @namespace Chart
     */


    core_controller.helpers = helpers$1;

    // @todo dispatch these helpers into appropriated helpers/helpers.* file and write unit tests!
    core_helpers(core_controller);

    core_controller._adapters = core_adapters;
    core_controller.Animation = core_animation;
    core_controller.animationService = core_animations;
    core_controller.controllers = controllers;
    core_controller.DatasetController = core_datasetController;
    core_controller.defaults = core_defaults;
    core_controller.Element = core_element;
    core_controller.elements = elements;
    core_controller.Interaction = core_interaction;
    core_controller.layouts = core_layouts;
    core_controller.platform = platform;
    core_controller.plugins = core_plugins;
    core_controller.Scale = core_scale;
    core_controller.scaleService = core_scaleService;
    core_controller.Ticks = core_ticks;
    core_controller.Tooltip = core_tooltip;

    // Register built-in scales

    core_controller.helpers.each(scales, function (scale, type) {
        core_controller.scaleService.registerScaleType(type, scale, scale._defaults);
    });

    // Load to register built-in adapters (as side effects)


    // Loading built-in plugins

    for (var k in plugins) {
        if (plugins.hasOwnProperty(k)) {
            core_controller.plugins.register(plugins[k]);
        }
    }

    core_controller.platform.initialize();

    var src = core_controller;
    if (typeof window !== 'undefined') {
        window.Chart = core_controller;
    }

    // DEPRECATIONS

    /**
     * Provided for backward compatibility, not available anymore
     * @namespace Chart.Chart
     * @deprecated since version 2.8.0
     * @todo remove at version 3
     * @private
     */
    core_controller.Chart = core_controller;

    /**
     * Provided for backward compatibility, not available anymore
     * @namespace Chart.Legend
     * @deprecated since version 2.1.5
     * @todo remove at version 3
     * @private
     */
    core_controller.Legend = plugins.legend._element;

    /**
     * Provided for backward compatibility, not available anymore
     * @namespace Chart.Title
     * @deprecated since version 2.1.5
     * @todo remove at version 3
     * @private
     */
    core_controller.Title = plugins.title._element;

    /**
     * Provided for backward compatibility, use Chart.plugins instead
     * @namespace Chart.pluginService
     * @deprecated since version 2.1.5
     * @todo remove at version 3
     * @private
     */
    core_controller.pluginService = core_controller.plugins;

    /**
     * Provided for backward compatibility, inheriting from Chart.PlugingBase has no
     * effect, instead simply create/register plugins via plain JavaScript objects.
     * @interface Chart.PluginBase
     * @deprecated since version 2.5.0
     * @todo remove at version 3
     * @private
     */
    core_controller.PluginBase = core_controller.Element.extend({});

    /**
     * Provided for backward compatibility, use Chart.helpers.canvas instead.
     * @namespace Chart.canvasHelpers
     * @deprecated since version 2.6.0
     * @todo remove at version 3
     * @private
     */
    core_controller.canvasHelpers = core_controller.helpers.canvas;

    /**
     * Provided for backward compatibility, use Chart.layouts instead.
     * @namespace Chart.layoutService
     * @deprecated since version 2.7.3
     * @todo remove at version 3
     * @private
     */
    core_controller.layoutService = core_controller.layouts;

    /**
     * Provided for backward compatibility, not available anymore.
     * @namespace Chart.LinearScaleBase
     * @deprecated since version 2.8
     * @todo remove at version 3
     * @private
     */
    core_controller.LinearScaleBase = scale_linearbase;

    /**
     * Provided for backward compatibility, instead we should create a new Chart
     * by setting the type in the config (`new Chart(id, {type: '{chart-type}'}`).
     * @deprecated since version 2.8.0
     * @todo remove at version 3
     */
    core_controller.helpers.each(
        [
            'Bar',
            'Bubble',
            'Doughnut',
            'Line',
            'PolarArea',
            'Radar',
            'Scatter'
        ],
        function (klass) {
            core_controller[klass] = function (ctx, cfg) {
                return new core_controller(ctx, core_controller.helpers.merge(cfg || {}, {
                    type: klass.charAt(0).toLowerCase() + klass.slice(1)
                }));
            };
        }
    );

    return src;

})));;
