/* @flow */
'use strict';

// http://dev.w3.org/csswg/css-color/

type ColorArray = [number, number, number, number | null];

const HEX3 = /^#([a-f0-9]{3})$/i;
const hex3 = (value: string): ColorArray | false => {
    const match = value.match(HEX3);
    if (match) {
        return [
            parseInt(match[1][0] + match[1][0], 16),
            parseInt(match[1][1] + match[1][1], 16),
            parseInt(match[1][2] + match[1][2], 16),
            null
        ];
    }
    return false;
};

const HEX6 = /^#([a-f0-9]{6})$/i;
const hex6 = (value: string): ColorArray | false => {
    const match = value.match(HEX6);
    if (match) {
        return [
            parseInt(match[1].substring(0, 2), 16),
            parseInt(match[1].substring(2, 4), 16),
            parseInt(match[1].substring(4, 6), 16),
            null
        ];
    }
    return false;
};

const RGB = /^rgb\(\s*(\d{1,3})\s*,\s*(\d{1,3})\s*,\s*(\d{1,3})\s*\)$/;
const rgb = (value: string): ColorArray | false => {
    const match = value.match(RGB);
    if (match) {
        return [Number(match[1]), Number(match[2]), Number(match[3]), null];
    }
    return false;
};

const RGBA = /^rgba\(\s*(\d{1,3})\s*,\s*(\d{1,3})\s*,\s*(\d{1,3})\s*,\s*(\d?\.?\d+)\s*\)$/;
const rgba = (value: string): ColorArray | false => {
    const match = value.match(RGBA);
    if (match && match.length > 4) {
        return [Number(match[1]), Number(match[2]), Number(match[3]), Number(match[4])];
    }
    return false;
};

const fromArray = (array: Array<number>): ColorArray => {
    return [
        Math.min(array[0], 255),
        Math.min(array[1], 255),
        Math.min(array[2], 255),
        array.length > 3 ? array[3] : null
    ];
};

const namedColor = (name: string): ColorArray | false => {
    const color: ColorArray | void = NAMED_COLORS[name.toLowerCase()];
    return color ? color : false;
};

export default class Color {
    r: number;
    g: number;
    b: number;
    a: number | null;

    constructor(value: string | Array<number>) {
        const [r, g, b, a] = Array.isArray(value)
            ? fromArray(value)
            : hex3(value) ||
              rgb(value) ||
              rgba(value) ||
              namedColor(value) ||
              hex6(value) || [0, 0, 0, null];
        this.r = r;
        this.g = g;
        this.b = b;
        this.a = a;
    }

    isTransparent(): boolean {
        return this.a === 0;
    }

    toString(): string {
        return this.a !== null && this.a !== 1
            ? `rgba(${this.r},${this.g},${this.b},${this.a})`
            : `rgb(${this.r},${this.g},${this.b})`;
    }
}

const NAMED_COLORS = {
    transparent: [0, 0, 0, 0],
    aliceblue: [240, 248, 255, null],
    antiquewhite: [250, 235, 215, null],
    aqua: [0, 255, 255, null],
    aquamarine: [127, 255, 212, null],
    azure: [240, 255, 255, null],
    beige: [245, 245, 220, null],
    bisque: [255, 228, 196, null],
    black: [0, 0, 0, null],
    blanchedalmond: [255, 235, 205, null],
    blue: [0, 0, 255, null],
    blueviolet: [138, 43, 226, null],
    brown: [165, 42, 42, null],
    burlywood: [222, 184, 135, null],
    cadetblue: [95, 158, 160, null],
    chartreuse: [127, 255, 0, null],
    chocolate: [210, 105, 30, null],
    coral: [255, 127, 80, null],
    cornflowerblue: [100, 149, 237, null],
    cornsilk: [255, 248, 220, null],
    crimson: [220, 20, 60, null],
    cyan: [0, 255, 255, null],
    darkblue: [0, 0, 139, null],
    darkcyan: [0, 139, 139, null],
    darkgoldenrod: [184, 134, 11, null],
    darkgray: [169, 169, 169, null],
    darkgreen: [0, 100, 0, null],
    darkgrey: [169, 169, 169, null],
    darkkhaki: [189, 183, 107, null],
    darkmagenta: [139, 0, 139, null],
    darkolivegreen: [85, 107, 47, null],
    darkorange: [255, 140, 0, null],
    darkorchid: [153, 50, 204, null],
    darkred: [139, 0, 0, null],
    darksalmon: [233, 150, 122, null],
    darkseagreen: [143, 188, 143, null],
    darkslateblue: [72, 61, 139, null],
    darkslategray: [47, 79, 79, null],
    darkslategrey: [47, 79, 79, null],
    darkturquoise: [0, 206, 209, null],
    darkviolet: [148, 0, 211, null],
    deeppink: [255, 20, 147, null],
    deepskyblue: [0, 191, 255, null],
    dimgray: [105, 105, 105, null],
    dimgrey: [105, 105, 105, null],
    dodgerblue: [30, 144, 255, null],
    firebrick: [178, 34, 34, null],
    floralwhite: [255, 250, 240, null],
    forestgreen: [34, 139, 34, null],
    fuchsia: [255, 0, 255, null],
    gainsboro: [220, 220, 220, null],
    ghostwhite: [248, 248, 255, null],
    gold: [255, 215, 0, null],
    goldenrod: [218, 165, 32, null],
    gray: [128, 128, 128, null],
    green: [0, 128, 0, null],
    greenyellow: [173, 255, 47, null],
    grey: [128, 128, 128, null],
    honeydew: [240, 255, 240, null],
    hotpink: [255, 105, 180, null],
    indianred: [205, 92, 92, null],
    indigo: [75, 0, 130, null],
    ivory: [255, 255, 240, null],
    khaki: [240, 230, 140, null],
    lavender: [230, 230, 250, null],
    lavenderblush: [255, 240, 245, null],
    lawngreen: [124, 252, 0, null],
    lemonchiffon: [255, 250, 205, null],
    lightblue: [173, 216, 230, null],
    lightcoral: [240, 128, 128, null],
    lightcyan: [224, 255, 255, null],
    lightgoldenrodyellow: [250, 250, 210, null],
    lightgray: [211, 211, 211, null],
    lightgreen: [144, 238, 144, null],
    lightgrey: [211, 211, 211, null],
    lightpink: [255, 182, 193, null],
    lightsalmon: [255, 160, 122, null],
    lightseagreen: [32, 178, 170, null],
    lightskyblue: [135, 206, 250, null],
    lightslategray: [119, 136, 153, null],
    lightslategrey: [119, 136, 153, null],
    lightsteelblue: [176, 196, 222, null],
    lightyellow: [255, 255, 224, null],
    lime: [0, 255, 0, null],
    limegreen: [50, 205, 50, null],
    linen: [250, 240, 230, null],
    magenta: [255, 0, 255, null],
    maroon: [128, 0, 0, null],
    mediumaquamarine: [102, 205, 170, null],
    mediumblue: [0, 0, 205, null],
    mediumorchid: [186, 85, 211, null],
    mediumpurple: [147, 112, 219, null],
    mediumseagreen: [60, 179, 113, null],
    mediumslateblue: [123, 104, 238, null],
    mediumspringgreen: [0, 250, 154, null],
    mediumturquoise: [72, 209, 204, null],
    mediumvioletred: [199, 21, 133, null],
    midnightblue: [25, 25, 112, null],
    mintcream: [245, 255, 250, null],
    mistyrose: [255, 228, 225, null],
    moccasin: [255, 228, 181, null],
    navajowhite: [255, 222, 173, null],
    navy: [0, 0, 128, null],
    oldlace: [253, 245, 230, null],
    olive: [128, 128, 0, null],
    olivedrab: [107, 142, 35, null],
    orange: [255, 165, 0, null],
    orangered: [255, 69, 0, null],
    orchid: [218, 112, 214, null],
    palegoldenrod: [238, 232, 170, null],
    palegreen: [152, 251, 152, null],
    paleturquoise: [175, 238, 238, null],
    palevioletred: [219, 112, 147, null],
    papayawhip: [255, 239, 213, null],
    peachpuff: [255, 218, 185, null],
    peru: [205, 133, 63, null],
    pink: [255, 192, 203, null],
    plum: [221, 160, 221, null],
    powderblue: [176, 224, 230, null],
    purple: [128, 0, 128, null],
    rebeccapurple: [102, 51, 153, null],
    red: [255, 0, 0, null],
    rosybrown: [188, 143, 143, null],
    royalblue: [65, 105, 225, null],
    saddlebrown: [139, 69, 19, null],
    salmon: [250, 128, 114, null],
    sandybrown: [244, 164, 96, null],
    seagreen: [46, 139, 87, null],
    seashell: [255, 245, 238, null],
    sienna: [160, 82, 45, null],
    silver: [192, 192, 192, null],
    skyblue: [135, 206, 235, null],
    slateblue: [106, 90, 205, null],
    slategray: [112, 128, 144, null],
    slategrey: [112, 128, 144, null],
    snow: [255, 250, 250, null],
    springgreen: [0, 255, 127, null],
    steelblue: [70, 130, 180, null],
    tan: [210, 180, 140, null],
    teal: [0, 128, 128, null],
    thistle: [216, 191, 216, null],
    tomato: [255, 99, 71, null],
    turquoise: [64, 224, 208, null],
    violet: [238, 130, 238, null],
    wheat: [245, 222, 179, null],
    white: [255, 255, 255, null],
    whitesmoke: [245, 245, 245, null],
    yellow: [255, 255, 0, null],
    yellowgreen: [154, 205, 50, null]
};

export const TRANSPARENT = new Color([0, 0, 0, 0]);