/**
 * Represents an RGB color and provides helper functions on it e.g. to get
 * color components in HSL color space.
 */
Ext.define('Ext.util.Color', {
    alternateClassName: 'Ext.draw.Color',
    statics: {
        colorToHexRe: /(.*?)rgb\((\d+),\s*(\d+),\s*(\d+)\)/,
        rgbToHexRe: /\s*rgb\((\d+),\s*(\d+),\s*(\d+)\)/,
        rgbaToHexRe: /\s*rgba\((\d+),\s*(\d+),\s*(\d+),\s*([\.\d]+)\)/,
        hexRe: /\s*#([0-9a-fA-F][0-9a-fA-F]?)([0-9a-fA-F][0-9a-fA-F]?)([0-9a-fA-F][0-9a-fA-F]?)\s*/,

        // Note that 'none' ia an invalid color string.
        // When assigned to the fillStyle/strokeStyle/shadowColor properties
        // of a Canvas context, those properties won't change their values.
        NONE: 'none',
        RGBA_NONE: 'rgba(0, 0, 0, 0)'
    },

    isColor: true,
    /**
     * @cfg {Number} lightnessFactor
     *
     * The default factor to compute the lighter or darker color.
     */
    lightnessFactor: 0.2,

    /**
     * @constructor
     * @param {Number} red Red component (0..255)
     * @param {Number} green Green component (0..255)
     * @param {Number} blue Blue component (0..255)
     * @param {Number} [alpha=1] (optional) Alpha component (0..1)
     */
    constructor: function (red, green, blue, alpha) {
        this.setRGB(red, green, blue, alpha);
    },

    clone: function() {
        var me = this;
        return new this.self(me.r, me.g, me.b, me.a);
    },

    setRGB: function (red, green, blue, alpha) {
        var me = this;
        me.r = Math.min(255, Math.max(0, red));
        me.g = Math.min(255, Math.max(0, green));
        me.b = Math.min(255, Math.max(0, blue));
        if (alpha === undefined) {
            me.a = 1;
        } else {
            me.a = Math.min(1, Math.max(0, alpha));
        }
    },

    /**
     * The the brightness of a color as defined by W3C:
     * https://www.w3.org/TR/AERT#color-contrast
     * @return {Number} The brightness, between `0` and `100`.
     */
    getBrightness: function() {
        var r = this.r / 255 * 100,
            g = this.g / 255 * 100,
            b = this.b / 255 * 100;

        return ((r * 299) + (g * 587) + (b * 114)) / 1000;
    },

    /**
     * Returns the gray value (0 to 255) of the color.
     *
     * The gray value is calculated using the formula r*0.3 + g*0.59 + b*0.11.
     *
     * @return {Number}
     */
    getGrayscale: function () {
        // http://en.wikipedia.org/wiki/Grayscale#Converting_color_to_grayscale
        return this.r * 0.3 + this.g * 0.59 + this.b * 0.11;
    },

    /**
     * Get the equivalent HSL components of the color.
     * @return {Number[]}
     */
    getHSL: function () {
        var me = this,
            r = me.r / 255,
            g = me.g / 255,
            b = me.b / 255,
            max = Math.max(r, g, b),
            min = Math.min(r, g, b),
            delta = max - min,
            h,
            s = 0,
            l = 0.5 * (max + min);

        // min==max means achromatic (hue is undefined)
        if (min !== max) {
            s = (l <= 0.5) ? delta / (max + min) : delta / (2 - max - min);
            if (r === max) {
                h = 60 * (g - b) / delta;
            } else if (g === max) {
                h = 120 + 60 * (b - r) / delta;
            } else {
                h = 240 + 60 * (r - g) / delta;
            }
            if (h < 0) {
                h += 360;
            }
            if (h >= 360) {
                h -= 360;
            }
        }

        return [h, s, l];
    },

    /**
     * Get the equivalent HSV components of the color.
     * @return {Number[]}
     */
    getHSV: function() {
        var me = this,
            r = me.r / 255,
            g = me.g / 255,
            b = me.b / 255,
            max = Math.max(r, g, b),
            min = Math.min(r, g, b),
            C = max - min,
            h,
            s = 0,
            v = max;

        // min == max means achromatic (hue is undefined)
        if (min != max) {
            s = v ? C / v : 0;
            if (r === max) {
                h = 60 * (g - b) / C;
            } else if (g === max) {
                h = 60 * (b - r) / C + 120;
            } else {
                h = 60 * (r - g) / C + 240;
            }
            if (h < 0) {
                h += 360;
            }
            if (h >= 360) {
                h -= 360;
            }
        }

        return [h, s, v];
    },

    /**
     * Set current color based on the specified HSL values.
     *
     * @param {Number} h Hue component [0..360)
     * @param {Number} s Saturation component [0..1]
     * @param {Number} l Lightness component [0..1]
     * @return {Ext.util.Color}
     */
    setHSL: function (h, s, l) {
        var me = this,
            abs = Math.abs,
            c, x, m;

        h = (h % 360 + 360 ) % 360;
        s = s > 1 ? 1 : s < 0 ? 0 : s;
        l = l > 1 ? 1 : l < 0 ? 0 : l;

        if (s === 0 || h === null) {
            l *= 255;
            me.setRGB(l, l, l);
        } else {
            // http://en.wikipedia.org/wiki/HSL_and_HSV#From_HSL
            h /= 60;
            c = s * (1 - abs(2 * l - 1));  // chroma
            x = c * (1 - abs(h % 2 - 1));  // second largest component
            m = l - c / 2;                 // lightness adjustment

            m *= 255;
            c *= 255;
            x *= 255;

            switch (Math.floor(h)) {
                case 0:
                    me.setRGB(c + m, x + m, m);
                    break;
                case 1:
                    me.setRGB(x + m, c + m, m);
                    break;
                case 2:
                    me.setRGB(m, c + m, x + m);
                    break;
                case 3:
                    me.setRGB(m, x + m, c + m);
                    break;
                case 4:
                    me.setRGB(x + m, m, c + m);
                    break;
                case 5:
                    me.setRGB(c + m, m, x + m);
                    break;
            }
        }
        return me;
    },

    /**
     * Set current color based on the specified HSV values.
     *
     * @param {Number} h Hue component [0..360)
     * @param {Number} s Saturation component [0..1]
     * @param {Number} v Value component [0..1]
     * @return {Ext.util.Color}
     */
    setHSV: function (h, s, v) {
        var me = this,
            c, x, m;

        h = (h % 360 + 360 ) % 360;
        s = s > 1 ? 1 : s < 0 ? 0 : s;
        v = v > 1 ? 1 : v < 0 ? 0 : v;

        if (s === 0 || h === null) {
            v *= 255;
            me.setRGB(v, v, v);
        } else {
            // http://en.wikipedia.org/wiki/HSL_and_HSV#From_HSV
            h /= 60;
            c = v * s;                          // chroma
            x = c * (1 - Math.abs(h % 2 - 1));  // second largest component
            m = v - c;                          // value adjustment

            m *= 255;
            c *= 255;
            x *= 255;

            switch (Math.floor(h)) {
                case 0:
                    me.setRGB(c + m, x + m, m);
                    break;
                case 1:
                    me.setRGB(x + m, c + m, m);
                    break;
                case 2:
                    me.setRGB(m, c + m, x + m);
                    break;
                case 3:
                    me.setRGB(m, x + m, c + m);
                    break;
                case 4:
                    me.setRGB(x + m, m, c + m);
                    break;
                case 5:
                    me.setRGB(c + m, m, x + m);
                    break;
            }
        }
        return me;
    },

    /**
     * Returns a new color that is lighter than this color in the HSL color space.
     * @param {Number} [factor=0.2] Lighter factor (0..1).
     * @return {Ext.util.Color}
     */
    createLighter: function (factor) {
        var color = this.clone();
        color.lighten(factor);
        return color;
    },

    /**
     * Lighten this color in the HSL color space.
     * @param {Number} [factor=0.2] Lighten factor (0..1).
     */
    lighten: function(factor) {
        if (!factor && factor !== 0) {
            factor = this.lightnessFactor;
        }
        var hsl = this.getHSL();
        this.setHSL(hsl[0], hsl[1], Ext.Number.constrain(hsl[2] + factor, 0, 1));
    },

    /**
     * Returns a new color that is darker than this color in the HSL color space.
     * @param {Number} [factor=0.2] Darker factor (0..1).
     * @return {Ext.util.Color}
     */
    createDarker: function (factor) {
        var color = this.clone();
        color.darken(factor);
        return color;
    },

    /**
     * Darken this color in the HSL color space.
     * @param {Number} [factor=0.2] Darken factor (0..1).
     */
    darken: function(factor) {
        if (!factor && factor !== 0) {
            factor = this.lightnessFactor;
        }
        return this.lighten(-factor);
    },

    /**
     * toString() returns a color in hex format ('#rrggbb') if the alpha is 1. If the 
     * alpha is less than one, toString() returns the color in RGBA format ('rgba(255,0,0,0.3)').
     * 
     * @return {String}
     */
    toString: function () {
        var me = this,
            round = Math.round;

        if (me.a === 1) {
            var r = round(me.r).toString(16),
                g = round(me.g).toString(16),
                b = round(me.b).toString(16);
            r = (r.length === 1) ? '0' + r : r;
            g = (g.length === 1) ? '0' + g : g;
            b = (b.length === 1) ? '0' + b : b;
            return ['#', r, g, b].join('');
        } else {
            return 'rgba(' + [
                round(me.r),
                round(me.g),
                round(me.b),
                me.a === 0 ? 0 : me.a.toFixed(15)
            ].join(', ') + ')';
            // Even though things like 'rgba(0,0,0,0)' will probably get converted to
            // 'rgba(0, 0, 0, 0)' when assigned to ctx.fillStyle or ctx.strokeStyle,
            // we can't be sure this is the case for every browser, so for consistency
            // with the Ext.draw.Color.RGBA_NONE (which is used a lot for checks)
            // we join using the ', ' and not ',' here.
        }
    },

    /**
     * Get this color in hexadecimal format.
     * @return {String} The color in hexadecimal format.
     */
    toHex: function (color) {
        var r = this.r,
            g = this.g,
            b = this.b,
            rgb = b | (g << 8) | (r << 16);

        return '#' + ('000000' + rgb.toString(16)).slice(-6);
    },

    /**
     * Parse the string and set the current color.
     *
     * Supported formats: 
     * 
     * + '#rrggbb'
     * + '#rgb', 'rgb(r,g,b)'
     * + 'rgba(r,g,b,a)'
     * + supported CSS color names (e.g., 'black', 'white', etc).
     *
     * If the string is not recognized, setFromString returns rgba(0,0,0,0).
     *
     * @param {String} Color Color as string.
     * @return this
     */
    setFromString: function (str) {
        var values, r, g, b, a = 1,
            parse = parseInt;

        if (str === Ext.util.Color.NONE) {
            this.r = this.g = this.b = this.a = 0;
            return this;
        }

        if ((str.length === 4 || str.length === 7) && str.substr(0, 1) === '#') {
            values = str.match(Ext.util.Color.hexRe);
            if (values) {
                r = parse(values[1], 16) >> 0;
                g = parse(values[2], 16) >> 0;
                b = parse(values[3], 16) >> 0;
                if (str.length === 4) {
                    r += (r * 16);
                    g += (g * 16);
                    b += (b * 16);
                }
            }
        }
        else if ((values = str.match(Ext.util.Color.rgbToHexRe))) {
            r = +values[1];
            g = +values[2];
            b = +values[3];
        } else if ((values = str.match(Ext.util.Color.rgbaToHexRe))) {
            r = +values[1];
            g = +values[2];
            b = +values[3];
            a = +values[4];
        } else {
            if (Ext.util.Color.ColorList.hasOwnProperty(str.toLowerCase())) {
                return this.setFromString(Ext.util.Color.ColorList[str.toLowerCase()]);
            }
        }
        if (typeof r === 'undefined') {
            return this;
        }
        this.r = r;
        this.g = g;
        this.b = b;
        this.a = a;
        return this;
    }
}, function () {
    var flyColor = new this();

    this.addStatics({
        /**
         * Returns a flyweight instance of Ext.util.Color.
         *
         * Can be called with either a CSS color string or with separate
         * arguments for red, green, blue, alpha.
         *
         * @param {Number/String} red Red component (0..255) or CSS color string.
         * @param {Number} [green] Green component (0..255)
         * @param {Number} [blue] Blue component (0..255)
         * @param {Number} [alpha=1] Alpha component (0..1)
         * @return {Ext.util.Color}
         * @static
         */
        fly: function (red, green, blue, alpha) {
            switch (arguments.length) {
                case 1:
                    flyColor.setFromString(red);
                    break;
                case 3:
                case 4:
                    flyColor.setRGB(red, green, blue, alpha);
                    break;
                default:
                    return null;
            }
            return flyColor;
        },

        ColorList: {
            aliceblue: '#f0f8ff',
            antiquewhite: '#faebd7',
            aqua: '#00ffff',
            aquamarine: '#7fffd4',
            azure: '#f0ffff',
            beige: '#f5f5dc',
            bisque: '#ffe4c4',
            black: '#000000',
            blanchedalmond: '#ffebcd',
            blue: '#0000ff',
            blueviolet: '#8a2be2',
            brown: '#a52a2a',
            burlywood: '#deb887',
            cadetblue: '#5f9ea0',
            chartreuse: '#7fff00',
            chocolate: '#d2691e',
            coral: '#ff7f50',
            cornflowerblue: '#6495ed',
            cornsilk: '#fff8dc',
            crimson: '#dc143c',
            cyan: '#00ffff',
            darkblue: '#00008b',
            darkcyan: '#008b8b',
            darkgoldenrod: '#b8860b',
            darkgray: '#a9a9a9',
            darkgreen: '#006400',
            darkkhaki: '#bdb76b',
            darkmagenta: '#8b008b',
            darkolivegreen: '#556b2f',
            darkorange: '#ff8c00',
            darkorchid: '#9932cc',
            darkred: '#8b0000',
            darksalmon: '#e9967a',
            darkseagreen: '#8fbc8f',
            darkslateblue: '#483d8b',
            darkslategray: '#2f4f4f',
            darkturquoise: '#00ced1',
            darkviolet: '#9400d3',
            deeppink: '#ff1493',
            deepskyblue: '#00bfff',
            dimgray: '#696969',
            dodgerblue: '#1e90ff',
            firebrick: '#b22222',
            floralwhite: '#fffaf0',
            forestgreen: '#228b22',
            fuchsia: '#ff00ff',
            gainsboro: '#dcdcdc',
            ghostwhite: '#f8f8ff',
            gold: '#ffd700',
            goldenrod: '#daa520',
            gray: '#808080',
            green: '#008000',
            greenyellow: '#adff2f',
            honeydew: '#f0fff0',
            hotpink: '#ff69b4',
            indianred: '#cd5c5c',
            indigo: '#4b0082',
            ivory: '#fffff0',
            khaki: '#f0e68c',
            lavender: '#e6e6fa',
            lavenderblush: '#fff0f5',
            lawngreen: '#7cfc00',
            lemonchiffon: '#fffacd',
            lightblue: '#add8e6',
            lightcoral: '#f08080',
            lightcyan: '#e0ffff',
            lightgoldenrodyellow: '#fafad2',
            lightgray: '#d3d3d3',
            lightgrey: '#d3d3d3',
            lightgreen: '#90ee90',
            lightpink: '#ffb6c1',
            lightsalmon: '#ffa07a',
            lightseagreen: '#20b2aa',
            lightskyblue: '#87cefa',
            lightslategray: '#778899',
            lightsteelblue: '#b0c4de',
            lightyellow: '#ffffe0',
            lime: '#00ff00',
            limegreen: '#32cd32',
            linen: '#faf0e6',
            magenta: '#ff00ff',
            maroon: '#800000',
            mediumaquamarine: '#66cdaa',
            mediumblue: '#0000cd',
            mediumorchid: '#ba55d3',
            mediumpurple: '#9370d8',
            mediumseagreen: '#3cb371',
            mediumslateblue: '#7b68ee',
            mediumspringgreen: '#00fa9a',
            mediumturquoise: '#48d1cc',
            mediumvioletred: '#c71585',
            midnightblue: '#191970',
            mintcream: '#f5fffa',
            mistyrose: '#ffe4e1',
            moccasin: '#ffe4b5',
            navajowhite: '#ffdead',
            navy: '#000080',
            oldlace: '#fdf5e6',
            olive: '#808000',
            olivedrab: '#6b8e23',
            orange: '#ffa500',
            orangered: '#ff4500',
            orchid: '#da70d6',
            palegoldenrod: '#eee8aa',
            palegreen: '#98fb98',
            paleturquoise: '#afeeee',
            palevioletred: '#d87093',
            papayawhip: '#ffefd5',
            peachpuff: '#ffdab9',
            peru: '#cd853f',
            pink: '#ffc0cb',
            plum: '#dda0dd',
            powderblue: '#b0e0e6',
            purple: '#800080',
            red: '#ff0000',
            rosybrown: '#bc8f8f',
            royalblue: '#4169e1',
            saddlebrown: '#8b4513',
            salmon: '#fa8072',
            sandybrown: '#f4a460',
            seagreen: '#2e8b57',
            seashell: '#fff5ee',
            sienna: '#a0522d',
            silver: '#c0c0c0',
            skyblue: '#87ceeb',
            slateblue: '#6a5acd',
            slategray: '#708090',
            snow: '#fffafa',
            springgreen: '#00ff7f',
            steelblue: '#4682b4',
            tan: '#d2b48c',
            teal: '#008080',
            thistle: '#d8bfd8',
            tomato: '#ff6347',
            turquoise: '#40e0d0',
            violet: '#ee82ee',
            wheat: '#f5deb3',
            white: '#ffffff',
            whitesmoke: '#f5f5f5',
            yellow: '#ffff00',
            yellowgreen: '#9acd32'
        },

        /**
         * Create a new color based on the specified HSL values.
         *
         * @param {Number} h Hue component [0..360)
         * @param {Number} s Saturation component [0..1]
         * @param {Number} l Lightness component [0..1]
         * @return {Ext.util.Color}
         * @static
         */
        fromHSL: function (h, s, l) {
            return (new this(0, 0, 0, 0)).setHSL(h, s, l);
        },

        /**
         * Create a new color based on the specified HSV values.
         *
         * @param {Number} h Hue component [0..360)
         * @param {Number} s Saturation component [0..1]
         * @param {Number} v Value component [0..1]
         * @return {Ext.util.Color}
         * @static
         */
        fromHSV: function (h, s, v) {
            return (new this(0, 0, 0, 0)).setHSL(h, s, v);
        },

        /**
         * Parse the string and create a new color.
         *
         * Supported formats: 
         * 
         * + '#rrggbb'
         * + '#rgb', 'rgb(r,g,b)'
         * + 'rgba(r,g,b,a)'
         * + supported CSS color names (e.g., 'black', 'white', etc).
         *
         * If the string is not recognized, fromString returns rgba(0,0,0,0).
         *
         * @param {String} color Color as string.
         * @return {Ext.util.Color}
         * @static
         */
        fromString: function (color) {
            return (new this(0, 0, 0, 0)).setFromString(color);
        },

        /**
         * Convenience method for creating a color.
         *
         * Can be called with several different combinations of arguments:
         *
         *     // Ext.util.Color is returned unchanged.
         *     Ext.util.Color.create(new Ext.util.color(255, 0, 0, 0));
         *
         *     // CSS color string.
         *     Ext.util.Color.create("red");
         *
         *     // Array of red, green, blue, alpha
         *     Ext.util.Color.create([255, 0, 0, 0]);
         *
         *     // Separate arguments of red, green, blue, alpha
         *     Ext.util.Color.create(255, 0, 0, 0);
         *
         *     // Returns black when no arguments given.
         *     Ext.util.Color.create();
         *
         * @param {Ext.util.Color/String/Number[]/Number} [red] Red component (0..255),
         * CSS color string or array of all components.
         * @param {Number} [green] Green component (0..255)
         * @param {Number} [blue] Blue component (0..255)
         * @param {Number} [alpha=1] Alpha component (0..1)
         * @return {Ext.util.Color}
         * @static
         */
        create: function (arg) {
            if (arg instanceof this) {
                return arg;
            } else if (Ext.isArray(arg)) {
                return new Ext.util.Color(arg[0], arg[1], arg[2], arg[3]);
            } else if (Ext.isString(arg)) {
                return Ext.util.Color.fromString(arg);
            } else if (arguments.length > 2) {
                return new Ext.util.Color(arguments[0], arguments[1], arguments[2], arguments[3]);
            } else {
                return new Ext.util.Color(0, 0, 0, 0);
            }
        }
    });
});