gradientservice.js

// TinyColor v1.4.1
// https://github.com/bgrins/TinyColor
// 2016-07-07, Brian Grinstead, MIT License
/*!
 * All credit goes to 
 * TinyGradient 0.3.1
 * Copyright 2014-2015 Damien "Mistic" Sorel (http://www.strangeplanet.fr)
 * Licensed under MIT (http://opensource.org/licenses/MIT)
 */

app.service('gradientService', function() {

    // Tiny color
    !function(a){function b(a,d){if(a=a?a:"",d=d||{},a instanceof b)return a;if(!(this instanceof b))return new b(a,d);var e=c(a);this._originalInput=a,this._r=e.r,this._g=e.g,this._b=e.b,this._a=e.a,this._roundA=P(100*this._a)/100,this._format=d.format||e.format,this._gradientType=d.gradientType,this._r<1&&(this._r=P(this._r)),this._g<1&&(this._g=P(this._g)),this._b<1&&(this._b=P(this._b)),this._ok=e.ok,this._tc_id=O++}function c(a){var b={r:0,g:0,b:0},c=1,e=null,g=null,i=null,j=!1,k=!1;return"string"==typeof a&&(a=K(a)),"object"==typeof a&&(J(a.r)&&J(a.g)&&J(a.b)?(b=d(a.r,a.g,a.b),j=!0,k="%"===String(a.r).substr(-1)?"prgb":"rgb"):J(a.h)&&J(a.s)&&J(a.v)?(e=G(a.s),g=G(a.v),b=h(a.h,e,g),j=!0,k="hsv"):J(a.h)&&J(a.s)&&J(a.l)&&(e=G(a.s),i=G(a.l),b=f(a.h,e,i),j=!0,k="hsl"),a.hasOwnProperty("a")&&(c=a.a)),c=z(c),{ok:j,format:a.format||k,r:Q(255,R(b.r,0)),g:Q(255,R(b.g,0)),b:Q(255,R(b.b,0)),a:c}}function d(a,b,c){return{r:255*A(a,255),g:255*A(b,255),b:255*A(c,255)}}function e(a,b,c){a=A(a,255),b=A(b,255),c=A(c,255);var d,e,f=R(a,b,c),g=Q(a,b,c),h=(f+g)/2;if(f==g)d=e=0;else{var i=f-g;switch(e=h>.5?i/(2-f-g):i/(f+g),f){case a:d=(b-c)/i+(c>b?6:0);break;case b:d=(c-a)/i+2;break;case c:d=(a-b)/i+4}d/=6}return{h:d,s:e,l:h}}function f(a,b,c){function d(a,b,c){return 0>c&&(c+=1),c>1&&(c-=1),1/6>c?a+6*(b-a)*c:.5>c?b:2/3>c?a+6*(b-a)*(2/3-c):a}var e,f,g;if(a=A(a,360),b=A(b,100),c=A(c,100),0===b)e=f=g=c;else{var h=.5>c?c*(1+b):c+b-c*b,i=2*c-h;e=d(i,h,a+1/3),f=d(i,h,a),g=d(i,h,a-1/3)}return{r:255*e,g:255*f,b:255*g}}function g(a,b,c){a=A(a,255),b=A(b,255),c=A(c,255);var d,e,f=R(a,b,c),g=Q(a,b,c),h=f,i=f-g;if(e=0===f?0:i/f,f==g)d=0;else{switch(f){case a:d=(b-c)/i+(c>b?6:0);break;case b:d=(c-a)/i+2;break;case c:d=(a-b)/i+4}d/=6}return{h:d,s:e,v:h}}function h(b,c,d){b=6*A(b,360),c=A(c,100),d=A(d,100);var e=a.floor(b),f=b-e,g=d*(1-c),h=d*(1-f*c),i=d*(1-(1-f)*c),j=e%6,k=[d,h,g,g,i,d][j],l=[i,d,d,h,g,g][j],m=[g,g,i,d,d,h][j];return{r:255*k,g:255*l,b:255*m}}function i(a,b,c,d){var e=[F(P(a).toString(16)),F(P(b).toString(16)),F(P(c).toString(16))];return d&&e[0].charAt(0)==e[0].charAt(1)&&e[1].charAt(0)==e[1].charAt(1)&&e[2].charAt(0)==e[2].charAt(1)?e[0].charAt(0)+e[1].charAt(0)+e[2].charAt(0):e.join("")}function j(a,b,c,d,e){var f=[F(P(a).toString(16)),F(P(b).toString(16)),F(P(c).toString(16)),F(H(d))];return e&&f[0].charAt(0)==f[0].charAt(1)&&f[1].charAt(0)==f[1].charAt(1)&&f[2].charAt(0)==f[2].charAt(1)&&f[3].charAt(0)==f[3].charAt(1)?f[0].charAt(0)+f[1].charAt(0)+f[2].charAt(0)+f[3].charAt(0):f.join("")}function k(a,b,c,d){var e=[F(H(d)),F(P(a).toString(16)),F(P(b).toString(16)),F(P(c).toString(16))];return e.join("")}function l(a,c){c=0===c?0:c||10;var d=b(a).toHsl();return d.s-=c/100,d.s=B(d.s),b(d)}function m(a,c){c=0===c?0:c||10;var d=b(a).toHsl();return d.s+=c/100,d.s=B(d.s),b(d)}function n(a){return b(a).desaturate(100)}function o(a,c){c=0===c?0:c||10;var d=b(a).toHsl();return d.l+=c/100,d.l=B(d.l),b(d)}function p(a,c){c=0===c?0:c||10;var d=b(a).toRgb();return d.r=R(0,Q(255,d.r-P(255*-(c/100)))),d.g=R(0,Q(255,d.g-P(255*-(c/100)))),d.b=R(0,Q(255,d.b-P(255*-(c/100)))),b(d)}function q(a,c){c=0===c?0:c||10;var d=b(a).toHsl();return d.l-=c/100,d.l=B(d.l),b(d)}function r(a,c){var d=b(a).toHsl(),e=(d.h+c)%360;return d.h=0>e?360+e:e,b(d)}function s(a){var c=b(a).toHsl();return c.h=(c.h+180)%360,b(c)}function t(a){var c=b(a).toHsl(),d=c.h;return[b(a),b({h:(d+120)%360,s:c.s,l:c.l}),b({h:(d+240)%360,s:c.s,l:c.l})]}function u(a){var c=b(a).toHsl(),d=c.h;return[b(a),b({h:(d+90)%360,s:c.s,l:c.l}),b({h:(d+180)%360,s:c.s,l:c.l}),b({h:(d+270)%360,s:c.s,l:c.l})]}function v(a){var c=b(a).toHsl(),d=c.h;return[b(a),b({h:(d+72)%360,s:c.s,l:c.l}),b({h:(d+216)%360,s:c.s,l:c.l})]}function w(a,c,d){c=c||6,d=d||30;var e=b(a).toHsl(),f=360/d,g=[b(a)];for(e.h=(e.h-(f*c>>1)+720)%360;--c;)e.h=(e.h+f)%360,g.push(b(e));return g}function x(a,c){c=c||6;for(var d=b(a).toHsv(),e=d.h,f=d.s,g=d.v,h=[],i=1/c;c--;)h.push(b({h:e,s:f,v:g})),g=(g+i)%1;return h}function y(a){var b={};for(var c in a)a.hasOwnProperty(c)&&(b[a[c]]=c);return b}function z(a){return a=parseFloat(a),(isNaN(a)||0>a||a>1)&&(a=1),a}function A(b,c){D(b)&&(b="100%");var d=E(b);return b=Q(c,R(0,parseFloat(b))),d&&(b=parseInt(b*c,10)/100),a.abs(b-c)<1e-6?1:b%c/parseFloat(c)}function B(a){return Q(1,R(0,a))}function C(a){return parseInt(a,16)}function D(a){return"string"==typeof a&&-1!=a.indexOf(".")&&1===parseFloat(a)}function E(a){return"string"==typeof a&&-1!=a.indexOf("%")}function F(a){return 1==a.length?"0"+a:""+a}function G(a){return 1>=a&&(a=100*a+"%"),a}function H(b){return a.round(255*parseFloat(b)).toString(16)}function I(a){return C(a)/255}function J(a){return!!V.CSS_UNIT.exec(a)}function K(a){a=a.replace(M,"").replace(N,"").toLowerCase();var b=!1;if(T[a])a=T[a],b=!0;else if("transparent"==a)return{r:0,g:0,b:0,a:0,format:"name"};var c;return(c=V.rgb.exec(a))?{r:c[1],g:c[2],b:c[3]}:(c=V.rgba.exec(a))?{r:c[1],g:c[2],b:c[3],a:c[4]}:(c=V.hsl.exec(a))?{h:c[1],s:c[2],l:c[3]}:(c=V.hsla.exec(a))?{h:c[1],s:c[2],l:c[3],a:c[4]}:(c=V.hsv.exec(a))?{h:c[1],s:c[2],v:c[3]}:(c=V.hsva.exec(a))?{h:c[1],s:c[2],v:c[3],a:c[4]}:(c=V.hex8.exec(a))?{r:C(c[1]),g:C(c[2]),b:C(c[3]),a:I(c[4]),format:b?"name":"hex8"}:(c=V.hex6.exec(a))?{r:C(c[1]),g:C(c[2]),b:C(c[3]),format:b?"name":"hex"}:(c=V.hex4.exec(a))?{r:C(c[1]+""+c[1]),g:C(c[2]+""+c[2]),b:C(c[3]+""+c[3]),a:I(c[4]+""+c[4]),format:b?"name":"hex8"}:(c=V.hex3.exec(a))?{r:C(c[1]+""+c[1]),g:C(c[2]+""+c[2]),b:C(c[3]+""+c[3]),format:b?"name":"hex"}:!1}function L(a){var b,c;return a=a||{level:"AA",size:"small"},b=(a.level||"AA").toUpperCase(),c=(a.size||"small").toLowerCase(),"AA"!==b&&"AAA"!==b&&(b="AA"),"small"!==c&&"large"!==c&&(c="small"),{level:b,size:c}}var M=/^\s+/,N=/\s+$/,O=0,P=a.round,Q=a.min,R=a.max,S=a.random;b.prototype={isDark:function(){return this.getBrightness()<128},isLight:function(){return!this.isDark()},isValid:function(){return this._ok},getOriginalInput:function(){return this._originalInput},getFormat:function(){return this._format},getAlpha:function(){return this._a},getBrightness:function(){var a=this.toRgb();return(299*a.r+587*a.g+114*a.b)/1e3},getLuminance:function(){var b,c,d,e,f,g,h=this.toRgb();return b=h.r/255,c=h.g/255,d=h.b/255,e=.03928>=b?b/12.92:a.pow((b+.055)/1.055,2.4),f=.03928>=c?c/12.92:a.pow((c+.055)/1.055,2.4),g=.03928>=d?d/12.92:a.pow((d+.055)/1.055,2.4),.2126*e+.7152*f+.0722*g},setAlpha:function(a){return this._a=z(a),this._roundA=P(100*this._a)/100,this},toHsv:function(){var a=g(this._r,this._g,this._b);return{h:360*a.h,s:a.s,v:a.v,a:this._a}},toHsvString:function(){var a=g(this._r,this._g,this._b),b=P(360*a.h),c=P(100*a.s),d=P(100*a.v);return 1==this._a?"hsv("+b+", "+c+"%, "+d+"%)":"hsva("+b+", "+c+"%, "+d+"%, "+this._roundA+")"},toHsl:function(){var a=e(this._r,this._g,this._b);return{h:360*a.h,s:a.s,l:a.l,a:this._a}},toHslString:function(){var a=e(this._r,this._g,this._b),b=P(360*a.h),c=P(100*a.s),d=P(100*a.l);return 1==this._a?"hsl("+b+", "+c+"%, "+d+"%)":"hsla("+b+", "+c+"%, "+d+"%, "+this._roundA+")"},toHex:function(a){return i(this._r,this._g,this._b,a)},toHexString:function(a){return"#"+this.toHex(a)},toHex8:function(a){return j(this._r,this._g,this._b,this._a,a)},toHex8String:function(a){return"#"+this.toHex8(a)},toRgb:function(){return{r:P(this._r),g:P(this._g),b:P(this._b),a:this._a}},toRgbString:function(){return 1==this._a?"rgb("+P(this._r)+", "+P(this._g)+", "+P(this._b)+")":"rgba("+P(this._r)+", "+P(this._g)+", "+P(this._b)+", "+this._roundA+")"},toPercentageRgb:function(){return{r:P(100*A(this._r,255))+"%",g:P(100*A(this._g,255))+"%",b:P(100*A(this._b,255))+"%",a:this._a}},toPercentageRgbString:function(){return 1==this._a?"rgb("+P(100*A(this._r,255))+"%, "+P(100*A(this._g,255))+"%, "+P(100*A(this._b,255))+"%)":"rgba("+P(100*A(this._r,255))+"%, "+P(100*A(this._g,255))+"%, "+P(100*A(this._b,255))+"%, "+this._roundA+")"},toName:function(){return 0===this._a?"transparent":this._a<1?!1:U[i(this._r,this._g,this._b,!0)]||!1},toFilter:function(a){var c="#"+k(this._r,this._g,this._b,this._a),d=c,e=this._gradientType?"GradientType = 1, ":"";if(a){var f=b(a);d="#"+k(f._r,f._g,f._b,f._a)}return"progid:DXImageTransform.Microsoft.gradient("+e+"startColorstr="+c+",endColorstr="+d+")"},toString:function(a){var b=!!a;a=a||this._format;var c=!1,d=this._a<1&&this._a>=0,e=!b&&d&&("hex"===a||"hex6"===a||"hex3"===a||"hex4"===a||"hex8"===a||"name"===a);return e?"name"===a&&0===this._a?this.toName():this.toRgbString():("rgb"===a&&(c=this.toRgbString()),"prgb"===a&&(c=this.toPercentageRgbString()),("hex"===a||"hex6"===a)&&(c=this.toHexString()),"hex3"===a&&(c=this.toHexString(!0)),"hex4"===a&&(c=this.toHex8String(!0)),"hex8"===a&&(c=this.toHex8String()),"name"===a&&(c=this.toName()),"hsl"===a&&(c=this.toHslString()),"hsv"===a&&(c=this.toHsvString()),c||this.toHexString())},clone:function(){return b(this.toString())},_applyModification:function(a,b){var c=a.apply(null,[this].concat([].slice.call(b)));return this._r=c._r,this._g=c._g,this._b=c._b,this.setAlpha(c._a),this},lighten:function(){return this._applyModification(o,arguments)},brighten:function(){return this._applyModification(p,arguments)},darken:function(){return this._applyModification(q,arguments)},desaturate:function(){return this._applyModification(l,arguments)},saturate:function(){return this._applyModification(m,arguments)},greyscale:function(){return 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e=b(a).toRgb(),f=b(c).toRgb(),g=d/100,h={r:(f.r-e.r)*g+e.r,g:(f.g-e.g)*g+e.g,b:(f.b-e.b)*g+e.b,a:(f.a-e.a)*g+e.a};return b(h)},b.readability=function(c,d){var e=b(c),f=b(d);return(a.max(e.getLuminance(),f.getLuminance())+.05)/(a.min(e.getLuminance(),f.getLuminance())+.05)},b.isReadable=function(a,c,d){var e,f,g=b.readability(a,c);switch(f=!1,e=L(d),e.level+e.size){case"AAsmall":case"AAAlarge":f=g>=4.5;break;case"AAlarge":f=g>=3;break;case"AAAsmall":f=g>=7}return f},b.mostReadable=function(a,c,d){var e,f,g,h,i=null,j=0;d=d||{},f=d.includeFallbackColors,g=d.level,h=d.size;for(var k=0;k<c.length;k++)e=b.readability(a,c[k]),e>j&&(j=e,i=b(c[k]));return b.isReadable(a,i,{level:g,size:h})||!f?i:(d.includeFallbackColors=!1,b.mostReadable(a,["#fff","#000"],d))};var T=b.names={aliceblue:"f0f8ff",antiquewhite:"faebd7",aqua:"0ff",aquamarine:"7fffd4",azure:"f0ffff",beige:"f5f5dc",bisque:"ffe4c4",black:"000",blanchedalmond:"ffebcd",blue:"00f",blueviolet:"8a2be2",brown:"a52a2a",burlywood:"deb887",burntsienna:"ea7e5d",cadetblue:"5f9ea0",chartreuse:"7fff00",chocolate:"d2691e",coral:"ff7f50",cornflowerblue:"6495ed",cornsilk:"fff8dc",crimson:"dc143c",cyan:"0ff",darkblue:"00008b",darkcyan:"008b8b",darkgoldenrod:"b8860b",darkgray:"a9a9a9",darkgreen:"006400",darkgrey:"a9a9a9",darkkhaki:"bdb76b",darkmagenta:"8b008b",darkolivegreen:"556b2f",darkorange:"ff8c00",darkorchid:"9932cc",darkred:"8b0000",darksalmon:"e9967a",darkseagreen:"8fbc8f",darkslateblue:"483d8b",darkslategray:"2f4f4f",darkslategrey:"2f4f4f",darkturquoise:"00ced1",darkviolet:"9400d3",deeppink:"ff1493",deepskyblue:"00bfff",dimgray:"696969",dimgrey:"696969",dodgerblue:"1e90ff",firebrick:"b22222",floralwhite:"fffaf0",forestgreen:"228b22",fuchsia:"f0f",gainsboro:"dcdcdc",ghostwhite:"f8f8ff",gold:"ffd700",goldenrod:"daa520",gray:"808080",green:"008000",greenyellow:"adff2f",grey:"808080",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",lightgreen:"90ee90",lightgrey:"d3d3d3",lightpink:"ffb6c1",lightsalmon:"ffa07a",lightseagreen:"20b2aa",lightskyblue:"87cefa",lightslategray:"789",lightslategrey:"789",lightsteelblue:"b0c4de",lightyellow:"ffffe0",lime:"0f0",limegreen:"32cd32",linen:"faf0e6",magenta:"f0f",maroon:"800000",mediumaquamarine:"66cdaa",mediumblue:"0000cd",mediumorchid:"ba55d3",mediumpurple:"9370db",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:"db7093",papayawhip:"ffefd5",peachpuff:"ffdab9",peru:"cd853f",pink:"ffc0cb",plum:"dda0dd",powderblue:"b0e0e6",purple:"800080",rebeccapurple:"663399",red:"f00",rosybrown:"bc8f8f",royalblue:"4169e1",saddlebrown:"8b4513",salmon:"fa8072",sandybrown:"f4a460",seagreen:"2e8b57",seashell:"fff5ee",sienna:"a0522d",silver:"c0c0c0",skyblue:"87ceeb",slateblue:"6a5acd",slategray:"708090",slategrey:"708090",snow:"fffafa",springgreen:"00ff7f",steelblue:"4682b4",tan:"d2b48c",teal:"008080",thistle:"d8bfd8",tomato:"ff6347",turquoise:"40e0d0",violet:"ee82ee",wheat:"f5deb3",white:"fff",whitesmoke:"f5f5f5",yellow:"ff0",yellowgreen:"9acd32"},U=b.hexNames=y(T),V=function(){var a="[-\\+]?\\d+%?",b="[-\\+]?\\d*\\.\\d+%?",c="(?:"+b+")|(?:"+a+")",d="[\\s|\\(]+("+c+")[,|\\s]+("+c+")[,|\\s]+("+c+")\\s*\\)?",e="[\\s|\\(]+("+c+")[,|\\s]+("+c+")[,|\\s]+("+c+")[,|\\s]+("+c+")\\s*\\)?";return{CSS_UNIT:new RegExp(c),rgb:new RegExp("rgb"+d),rgba:new RegExp("rgba"+e),hsl:new RegExp("hsl"+d),hsla:new RegExp("hsla"+e),hsv:new RegExp("hsv"+d),hsva:new RegExp("hsva"+e),hex3:/^#?([0-9a-fA-F]{1})([0-9a-fA-F]{1})([0-9a-fA-F]{1})$/,hex6:/^#?([0-9a-fA-F]{2})([0-9a-fA-F]{2})([0-9a-fA-F]{2})$/,hex4:/^#?([0-9a-fA-F]{1})([0-9a-fA-F]{1})([0-9a-fA-F]{1})([0-9a-fA-F]{1})$/,hex8:/^#?([0-9a-fA-F]{2})([0-9a-fA-F]{2})([0-9a-fA-F]{2})([0-9a-fA-F]{2})$/}}();"undefined"!=typeof module&&module.exports?module.exports=b:"function"==typeof define&&define.amd?define(function(){return b}):window.tinycolor=b}(Math);


    var Utils = {
        rgba_max: { r: 256, g: 256, b: 256, a: 1 },
        hsva_max: { h: 360, s: 1, v: 1, a: 1 },

        /**
         * Linearly compute the step size between start and end (not normalized)
         * @param {Object} start - rgba or hsva
         * @param {Object} end - rgba or hsva
         * @param {Integer} steps - number of desired steps
         * @return {Object} rgba or hsva
         */
        stepize: function(start, end, steps) {
            var step = {};

            for (var k in start) {
                if (start.hasOwnProperty(k)) {
                    step[k] = (end[k]-start[k]) / steps;
                }
            }

            return step;
        },

        /**
         * Compute the final step color
         * @param {Object} step - rgba or hsva from `stepize`
         * @param {Object} start - rgba or hsva
         * @param {Integer} i - color index
         * @param {Object} max - rgba or hsva of maximum values for each channel
         * @return {Object} rgba or hsva
         */
        interpolate: function(step, start, i, max) {
            var color = {};

            for (var k in start) {
                if (start.hasOwnProperty(k)) {
                    color[k] = step[k] * i + start[k];
                    color[k] = color[k]<0 ? color[k]+max[k] : ( max[k]!=1 ? color[k]%max[k] : color[k] );
                }
            }

            return color;
        },

        /**
         * Generate gradient with RGBa interpolation
         * @param {Object} stop1
         * @param {Object} stop2
         * @param {Integer} steps
         * @param {tinycolor[]} color1 included, color2 excluded
         */
        rgb: function(stop1, stop2, steps) {
            var start = stop1.color.toRgb(),
                end = stop2.color.toRgb(),
                gradient = [stop1.color],
                step = Utils.stepize(start, end, steps),
                color;

            for (var i=1; i<steps; i++) {
                color = Utils.interpolate(step, start, i, Utils.rgba_max);
                gradient.push(tinycolor(color));
            }

            return gradient;
        },

        /**
         * Generate gradient with HSVa interpolation
         * @param {Object} stop1
         * @param {Object} stop2
         * @param {Integer} steps
         * @param {Boolean} trigonometric - true to step in trigonometric order
         * @param {tinycolor[]} color1 included, color2 excluded
         */
        hsv: function(stop1, stop2, steps, trigonometric) {
            var start = stop1.color.toHsv(),
                end = stop2.color.toHsv(),
                gradient = [stop1.color],
                step = Utils.stepize(start, end, steps),
                diff, color;

            // recompute hue
            if ((start.h <= end.h && !trigonometric) || (start.h >= end.h && trigonometric)) {
                diff = end.h-start.h;
            }
            else if (trigonometric) {
                diff = 360-end.h+start.h;
            }
            else {
                diff = 360-start.h+end.h;
            }
            step.h = Math.pow(-1, trigonometric) * Math.abs(diff)*1.0 / steps;

            for (var i=1; i<steps; i++) {
                color = Utils.interpolate(step, start, i, Utils.hsva_max);
                gradient.push(tinycolor(color));
            }

            return gradient;
        },

        /**
         * Compute substeps between each stops
         * @param {Object[]} stops
         * @param {Integer} steps
         * @return {Integer[]}
         */
        substeps: function(stops, steps) {
            var l = stops.length;

            // validation
            steps = parseInt(steps);

            if (isNaN(steps) || steps < 2) {
                throw new Error('Invalid number of steps (< 2)');
            }
            if (steps < l) {
                throw new Error('Number of steps cannot be inferior to number of stops');
            }

            // compute substeps from stop positions
            var substeps = [];

            for (var i=1; i<l; i++) {
                var step = (steps-1) * (stops[i].pos-stops[i-1].pos);
                substeps.push(Math.max(1, Math.round(step)));
            }

            // adjust number of steps
            var totalSubsteps = 1;
            for (var n=l-1; n--;) totalSubsteps+= substeps[n];

            while (totalSubsteps != steps) {
                if (totalSubsteps < steps) {
                    var min = Math.min.apply(null, substeps);
                    substeps[substeps.indexOf(min)]++;
                    totalSubsteps++;
                }
                else {
                    var max = Math.max.apply(null, substeps);
                    substeps[substeps.indexOf(max)]--;
                    totalSubsteps--;
                }
            }

            return substeps;
        }
    };

    /**
     * @class tinygradient
     * @param {mixed} stops
     */

    var TinyGradient = function(stops) {
        // varargs
        if (arguments.length == 1) {
            if (!(arguments[0] instanceof Array)) {
                throw new Error('"stops" is not an array');
            }
            stops = arguments[0];
        }
        else {
            stops = Array.prototype.slice.call(arguments);
        }

        // if we are called as a function, call using new instead
        if (!(this instanceof TinyGradient)) {
            return new TinyGradient(stops);
        }

        // validation
        if (stops.length < 2) {
            throw new Error('Invalid number of stops (< 2)');
        }

        var havingPositions = stops[0].pos !== undefined,
            l = stops.length,
            p = -1;
        // create tinycolor objects and clean positions
        this.stops = stops.map(function(stop, i) {
            var hasPosition = stop.pos !== undefined;
            if (havingPositions ^ hasPosition) {
                throw new Error('Cannot mix positionned and not posionned color stops');
            }

            if (hasPosition) {
                stop = {
                    color: tinycolor(stop.color),
                    pos: stop.pos
                };

                if (stop.pos < 0 || stop.pos > 1) {
                    throw new Error('Color stops positions must be between 0 and 1');
                }
                else if (stop.pos <= p) {
                    throw new Error('Color stops positions are not ordered');
                }
                p = stop.pos;
            }
            else {
                stop = {
                    color: tinycolor(stop),
                    pos: i/(l-1)
                };
            }

            return stop;
        });

        if (this.stops[0].pos !== 0) {
            this.stops.unshift({
                color: this.stops[0].color,
                pos: 0
            });
        }
        if (this.stops[this.stops.length-1].pos !== 1) {
            this.stops.push({
                color: this.stops[this.stops.length-1].color,
                pos: 1
            });
        }
    };

    /**
     * Return new instance with reversed stops
     * @return {tinygradient}
     */
    TinyGradient.prototype.reverse = function() {
        var stops = [];

        this.stops.forEach(function(stop) {
            stops.push({
                color: stop.color,
                pos: 1 - stop.pos
            });
        });

        return new TinyGradient(stops.reverse());
    };

    /**
     * Generate gradient with RGBa interpolation
     * @param {Integer} steps
     * @return {tinycolor[]}
     */
    TinyGradient.prototype.rgb = function(steps) {
        var substeps = Utils.substeps(this.stops, steps),
            gradient = [];

        for (var i=0, l=this.stops.length; i<l-1; i++) {
            gradient = gradient.concat(Utils.rgb(this.stops[i], this.stops[i+1], substeps[i]));
        }

        gradient.push(this.stops[l-1].color);

        return gradient;
    };

    /**
     * Generate gradient with HSVa interpolation
     * @param {Integer} steps
     * @param {Boolean|String} [mode=false]
     *    - false to step in clockwise
     *    - true to step in trigonometric order
     *    - 'short' to use the shortest way
     *    - 'long' to use the longest way
     * @return {tinycolor[]}
     */
    TinyGradient.prototype.hsv = function(steps, mode) {
        var substeps = Utils.substeps(this.stops, steps),
            trigonometric = mode === true,
            parametrized = typeof mode === 'string',
            gradient = [],
            start, end, trig;

        for (var i=0, l=this.stops.length; i<l-1; i++) {
            start = this.stops[i].color.toHsv();
            end = this.stops[i+1].color.toHsv();
                
            if (parametrized) {
                trig = (start.h < end.h && end.h-start.h < 180) || (start.h > end.h && start.h-end.h > 180);
            }
            
            // rgb interpolation if one of the steps in grayscale
            if (start.s===0 || end.s===0) {
                gradient = gradient.concat(Utils.rgb(this.stops[i], this.stops[i+1], substeps[i]));
            }
            else {
                gradient = gradient.concat(Utils.hsv(this.stops[i], this.stops[i+1], substeps[i],
                  (mode==='long' && trig) || (mode==='short' && !trig) || (!parametrized && trigonometric)
                ));
            }
        }

        gradient.push(this.stops[l-1].color);

        return gradient;
    };

    /**
     * Generate CSS3 command (no prefix) for this gradient
     * @param {String} [mode=linear] - 'linear' or 'radial'
     * @param {String} [direction] - default is 'to right' or 'ellipse at center'
     * @return {String}
     */
    TinyGradient.prototype.css = function(mode, direction) {
        mode = mode || 'linear';
        direction = direction || (mode=='linear' ? 'to right' : 'ellipse at center');

        var css = mode + '-gradient(' + direction;
        this.stops.forEach(function(stop) {
            css+= ', ' + stop.color.toRgbString() + ' ' + (stop.pos*100) + '%';
        });
        css+= ')';
        return css;
    };


    /**
     * Initialize and create gradient with RGBa interpolation
     * @see TinyGradient::rgb
     */
    TinyGradient.rgb = function(colors, steps) {
        colors = Array.prototype.slice.call(arguments);
        steps = colors.pop();

        return TinyGradient.apply(null, colors).rgb(steps);
    };

    /**
     * Initialize and create gradient with HSVa interpolation
     * @see TinyGradient::hsv
     */
    TinyGradient.hsv = function(colors, steps, mode) {
        colors = Array.prototype.slice.call(arguments);
        mode = colors.pop();
        steps = colors.pop();

        return TinyGradient.apply(null, colors).hsv(steps, mode);
    };

    /**
     * Initialize and generate CSS3 command for gradient
     * @see TinyGradient::css
     */
    TinyGradient.css = function(colors, mode, direction) {
        colors = Array.prototype.slice.call(arguments);
        direction = colors.pop();
        mode = colors.pop();

        return TinyGradient.apply(null, colors).css(mode, direction);
    };


    this.RGBGradient = function(x,steps){
        colors = TinyGradient(x);
        colors = colors.rgb(steps);
        output = [];
        colors.forEach(function(d){
            r = Math.round(d._r);
            g = Math.round(d._g);
            b = Math.round(d._b);
            temp = 'rgb(' + r + ',' + g + ',' + b + ')'
            temp = tinycolor(temp);
            output.push(temp.toHexString());

        })
        return output;
    }

    this.HSVGradient = function(x,steps){
        colors = TinyGradient(x);
        colors = colors.hsv(steps);
        output = [];
        colors.forEach(function(d){
            r = Math.round(d._r);
            g = Math.round(d._g);
            b = Math.round(d._b);
            temp = 'rgb(' + r + ',' + g + ',' + b + ')'
            temp = tinycolor(temp);
            output.push(temp.toHexString());

        })
        return output;
    }


});