node-less/lib/color.js

Less Compiler For Node

(function (module) {

    var operate = require('./operate.js');

    var Color = function (rgb, a) {
        if (Array.isArray(rgb)) {
            this.rgb = rgb;
        } else if (rgb.length == 6) {
            this.rgb = rgb.match(/.{2}/g).map(function (c) {
                return parseInt(c, 16);
            });
        } else {
            this.rgb = rgb.split('').map(function (c) {
                return parseInt(c + c, 16);
            });
        }
        this.alpha = typeof(a) === 'number' ? a : 1;
    };

    Color.prototype = {
        type: "Color",
        eval: function () { return this },
        luma: function () { return (0.2126 * this.rgb[0] / 255) + (0.7152 * this.rgb[1] / 255) + (0.0722 * this.rgb[2] / 255); },
        toCSS: function (env, doNotCompress) {
            var compress = env && env.compress && !doNotCompress;
            if (this.alpha < 1.0) {
                return "rgba(" + this.rgb.map(function (c) {
                    return Math.round(c);
                }).concat(this.alpha).join(',' + (compress ? '' : ' ')) + ")";
            } else {
                var color = this.rgb.map(function (i) {
                    i = Math.round(i);
                    i = (i > 255 ? 255 : (i < 0 ? 0 : i)).toString(16);
                    return i.length === 1 ? '0' + i : i;
                }).join('');
                if (compress) {
                    color = color.split('');
                    if (color[0] == color[1] && color[2] == color[3] && color[4] == color[5]) {
                        color = color[0] + color[2] + color[4];
                    } else {
                        color = color.join('');
                    }
                }
                return '#' + color;
            }
        },
        operate: function (env, op, other) {
            var result = [];
            if (! (other instanceof Color)) {
                other = other.toColor();
            }
            for (var c = 0; c < 3; c++) {
                result[c] = operate(env, op, this.rgb[c], other.rgb[c]);
            }
            return new Color(result, this.alpha + other.alpha);
        },

        toHSL: function () {
            var r = this.rgb[0] / 255,
                g = this.rgb[1] / 255,
                b = this.rgb[2] / 255,
                a = this.alpha;
            var max = Math.max(r, g, b), min = Math.min(r, g, b);
            var h, s, l = (max + min) / 2, d = max - min;
            if (max === min) {
                h = s = 0;
            } else {
                s = l > 0.5 ? d / (2 - max - min) : d / (max + min);
                switch (max) {
                    case r: h = (g - b) / d + (g < b ? 6 : 0); break;
                    case g: h = (b - r) / d + 2;               break;
                    case b: h = (r - g) / d + 4;               break;
                }
                h /= 6;
            }
            return { h: h * 360, s: s, l: l, a: a };
        },
        toHSV: function () {
            var r = this.rgb[0] / 255,
                g = this.rgb[1] / 255,
                b = this.rgb[2] / 255,
                a = this.alpha;
            var max = Math.max(r, g, b), min = Math.min(r, g, b);
            var h, s, v = max;
            var d = max - min;
            if (max === 0) {
                s = 0;
            } else {
                s = d / max;
            }
            if (max === min) {
                h = 0;
            } else {
                switch(max){
                    case r: h = (g - b) / d + (g < b ? 6 : 0); break;
                    case g: h = (b - r) / d + 2; break;
                    case b: h = (r - g) / d + 4; break;
                }
                h /= 6;
            }
            return { h: h * 360, s: s, v: v, a: a };
        },
        toARGB: function () {
            var argb = [Math.round(this.alpha * 255)].concat(this.rgb);
            return '#' + argb.map(function (i) {
                i = Math.round(i);
                i = (i > 255 ? 255 : (i < 0 ? 0 : i)).toString(16);
                return i.length === 1 ? '0' + i : i;
            }).join('');
        },
        compare: function (x) {
            if (!x.rgb) {
                return -1;
            }
            return (x.rgb[0] === this.rgb[0] &&
                x.rgb[1] === this.rgb[1] &&
                x.rgb[2] === this.rgb[2] &&
                x.alpha === this.alpha) ? 0 : -1;
        }
    };

    module.exports = Color;

})(module);