/*

Holder - 2.0 - client side image placeholders

(c) 2012-2013 Ivan Malopinsky / http://imsky.co

Provided under the Apache 2.0 License: http://www.apache.org/licenses/LICENSE-2.0

Commercial use requires attribution.

*/

var Holder = Holder || {};

(function (app, win) {

var preempted = false,

fallback = false,

canvas = document.createElement('canvas');

//getElementsByClassName polyfill

document.getElementsByClassName||(document.getElementsByClassName=function(e){var t=document,n,r,i,s=[];if(t.querySelectorAll)return t.querySelectorAll("."+e);if(t.evaluate){r=".//*[contains(concat(' ', @class, ' '), ' "+e+" ')]",n=t.evaluate(r,t,null,0,null);while(i=n.iterateNext())s.push(i)}else{n=t.getElementsByTagName("*"),r=new RegExp("(^|\\s)"+e+"(\\s|$)");for(i=0;i<n.length;i++)r.test(n[i].className)&&s.push(n[i])}return s})

//getComputedStyle polyfill

window.getComputedStyle||(window.getComputedStyle=function(e,t){return this.el=e,this.getPropertyValue=function(t){var n=/(\-([a-z]){1})/g;return t=="float"&&(t="styleFloat"),n.test(t)&&(t=t.replace(n,function(){return arguments[2].toUpperCase()})),e.currentStyle[t]?e.currentStyle[t]:null},this})

//http://javascript.nwbox.com/ContentLoaded by Diego Perini with modifications

function contentLoaded(n,t){var l="complete",s="readystatechange",u=!1,h=u,c=!0,i=n.document,a=i.documentElement,e=i.addEventListener?"addEventListener":"attachEvent",v=i.addEventListener?"removeEventListener":"detachEvent",f=i.addEventListener?"":"on",r=function(e){(e.type!=s||i.readyState==l)&&((e.type=="load"?n:i)[v](f+e.type,r,u),!h&&(h=!0)&&t.call(n,null))},o=function(){try{a.doScroll("left")}catch(n){setTimeout(o,50);return}r("poll")};if(i.readyState==l)t.call(n,"lazy");else{if(i.createEventObject&&a.doScroll){try{c=!n.frameElement}catch(y){}c&&o()}i[e](f+"DOMContentLoaded",r,u),i[e](f+s,r,u),n[e](f+"load",r,u)}};

//https://gist.github.com/991057 by Jed Schmidt with modifications

function selector(a){

	a=a.match(/^(\W)?(.*)/);var b=document["getElement"+(a[1]?a[1]=="#"?"ById":"sByClassName":"sByTagName")](a[2]);

	var ret=[];	b!=null&&(b.length?ret=b:b.length==0?ret=b:ret=[b]);	return ret;

}

//shallow object property extend

function extend(a,b){var c={};for(var d in a)c[d]=a[d];for(var e in b)c[e]=b[e];return c}

//hasOwnProperty polyfill

if (!Object.prototype.hasOwnProperty)

	Object.prototype.hasOwnProperty = function(prop) {

		var proto = this.__proto__ || this.constructor.prototype;

		return (prop in this) && (!(prop in proto) || proto[prop] !== this[prop]);

	}

function text_size(width, height, template) {

	height = parseInt(height,10);

	width = parseInt(width,10);

	var bigSide = Math.max(height, width)

	var smallSide = Math.min(height, width)

	var scale = 1 / 12;

	var newHeight = Math.min(smallSide * 0.75, 0.75 * bigSide * scale);

	return {

		height: Math.round(Math.max(template.size, newHeight))

	}

}

function draw(ctx, dimensions, template, ratio) {

	var ts = text_size(dimensions.width, dimensions.height, template);

	var text_height = ts.height;

	var width = dimensions.width * ratio,

		height = dimensions.height * ratio;

	var font = template.font ? template.font : "sans-serif";

	canvas.width = width;

	canvas.height = height;

	ctx.textAlign = "center";

	ctx.textBaseline = "middle";

	ctx.fillStyle = template.background;

	ctx.fillRect(0, 0, width, height);

	ctx.fillStyle = template.foreground;

	ctx.font = "bold " + text_height + "px " + font;

	var text = template.text ? template.text : (Math.floor(dimensions.width) + "x" + Math.floor(dimensions.height));

	var text_width = ctx.measureText(text).width;

	if (text_width / width >= 0.75) {

		text_height = Math.floor(text_height * 0.75 * (width/text_width));

	}

	//Resetting font size if necessary

	ctx.font = "bold " + (text_height * ratio) + "px " + font;

	ctx.fillText(text, (width / 2), (height / 2), width);

	return canvas.toDataURL("image/png");

}

function render(mode, el, holder, src) {

	var dimensions = holder.dimensions,

		theme = holder.theme,

		text = holder.text ? decodeURIComponent(holder.text) : holder.text;

	var dimensions_caption = dimensions.width + "x" + dimensions.height;

	theme = (text ? extend(theme, {

		text: text

	}) : theme);

	theme = (holder.font ? extend(theme, {

		font: holder.font

	}) : theme);

	if (mode == "image") {

		el.setAttribute("data-src", src);

		el.setAttribute("alt", text ? text : theme.text ? theme.text + " [" + dimensions_caption + "]" : dimensions_caption);

		if (fallback || !holder.auto) {

			el.style.width = dimensions.width + "px";

			el.style.height = dimensions.height + "px";

		}

		if (fallback) {

			el.style.backgroundColor = theme.background;

		} else {

			el.setAttribute("src", draw(ctx, dimensions, theme, ratio));

		}

	} else if (mode == "background") {

		if (!fallback) {

			el.style.backgroundImage = "url(" + draw(ctx, dimensions, theme, ratio) + ")";

			el.style.backgroundSize = dimensions.width + "px " + dimensions.height + "px";

		}

	} else if (mode == "fluid") {

		el.setAttribute("data-src", src);

		el.setAttribute("alt", text ? text : theme.text ? theme.text + " [" + dimensions_caption + "]" : dimensions_caption);

		if (dimensions.height.substr(-1) == "%") {

			el.style.height = dimensions.height

		} else {

			el.style.height = dimensions.height + "px"

		}

		if (dimensions.width.substr(-1) == "%") {

			el.style.width = dimensions.width

		} else {

			el.style.width = dimensions.width + "px"

		}

		if (el.style.display == "inline" || el.style.display == "") {

			el.style.display = "block";

		}

		if (fallback) {

			el.style.backgroundColor = theme.background;

		} else {

			el.holderData = holder;

			fluid_images.push(el);

			fluid_update(el);

		}

	}

};

function fluid_update(element) {

	var images;

	if (element.nodeType == null) {

		images = fluid_images;

	} else {

		images = [element]

	}

	for (i in images) {

		var el = images[i]

		if (el.holderData) {

			var holder = el.holderData;

			el.setAttribute("src", draw(ctx, {

				height: el.clientHeight,

				width: el.clientWidth

			}, holder.theme, ratio));

		}

	}

}

function parse_flags(flags, options) {

	var ret = {

		theme: settings.themes.gray

	}, render = false;

	for (sl = flags.length, j = 0; j < sl; j++) {

		var flag = flags[j];

		if (app.flags.dimensions.match(flag)) {

			render = true;

			ret.dimensions = app.flags.dimensions.output(flag);

		} else if (app.flags.fluid.match(flag)) {

			render = true;

			ret.dimensions = app.flags.fluid.output(flag);

			ret.fluid = true;

		} else if (app.flags.colors.match(flag)) {

			ret.theme = app.flags.colors.output(flag);

		} else if (options.themes[flag]) {

			//If a theme is specified, it will override custom colors

			ret.theme = options.themes[flag];

		} else if (app.flags.text.match(flag)) {

			ret.text = app.flags.text.output(flag);

		} else if (app.flags.font.match(flag)) {

			ret.font = app.flags.font.output(flag);

		} else if (app.flags.auto.match(flag)) {

			ret.auto = true;

		}

	}

	return render ? ret : false;

};

if (!canvas.getContext) {

	fallback = true;

} else {

	if (canvas.toDataURL("image/png")

		.indexOf("data:image/png") < 0) {

		//Android doesn't support data URI

		fallback = true;

	} else {

		var ctx = canvas.getContext("2d");

	}

}

var dpr = 1, bsr = 1;

if(!fallback){

    dpr = window.devicePixelRatio || 1,

    bsr = ctx.webkitBackingStorePixelRatio || ctx.mozBackingStorePixelRatio || ctx.msBackingStorePixelRatio || ctx.oBackingStorePixelRatio || ctx.backingStorePixelRatio || 1;

}

var ratio = dpr / bsr;

var fluid_images = [];

var settings = {

	domain: "holder.js",

	images: "img",

	bgnodes: ".holderjs",

	themes: {

		"gray": {

			background: "#eee",

			foreground: "#aaa",

			size: 12

		},

		"social": {

			background: "#3a5a97",

			foreground: "#fff",

			size: 12

		},

		"industrial": {

			background: "#434A52",

			foreground: "#C2F200",

			size: 12

		}

	},

	stylesheet: ".holderjs-fluid {font-size:16px;font-weight:bold;text-align:center;font-family:sans-serif;margin:0}"

};

app.flags = {

	dimensions: {

		regex: /^(\d+)x(\d+)$/,

		output: function (val) {

			var exec = this.regex.exec(val);

			return {

				width: +exec[1],

				height: +exec[2]

			}

		}

	},

	fluid: {

		regex: /^([0-9%]+)x([0-9%]+)$/,

		output: function (val) {

			var exec = this.regex.exec(val);

			return {

				width: exec[1],

				height: exec[2]

			}

		}

	},

	colors: {

		regex: /#([0-9a-f]{3,})\:#([0-9a-f]{3,})/i,

		output: function (val) {

			var exec = this.regex.exec(val);

			return {

				size: settings.themes.gray.size,

				foreground: "#" + exec[2],

				background: "#" + exec[1]

			}

		}

	},

	text: {

		regex: /text\:(.*)/,

		output: function (val) {

			return this.regex.exec(val)[1];

		}

	},

	font: {

		regex: /font\:(.*)/,

		output: function (val) {

			return this.regex.exec(val)[1];

		}

	},

	auto: {

		regex: /^auto$/

	}

}

for (var flag in app.flags) {

	if (!app.flags.hasOwnProperty(flag)) continue;

	app.flags[flag].match = function (val) {

		return val.match(this.regex)

	}

}

app.add_theme = function (name, theme) {

	name != null && theme != null && (settings.themes[name] = theme);

	return app;

};

app.add_image = function (src, el) {

	var node = selector(el);

	if (node.length) {

		for (var i = 0, l = node.length; i < l; i++) {

			var img = document.createElement("img")

			img.setAttribute("data-src", src);

			node[i].appendChild(img);

		}

	}

	return app;

};

app.run = function (o) {

	var options = extend(settings, o),

	    images = [], imageNodes = [], bgnodes = [];

	if(typeof(options.images) == "string"){

	    imageNodes = selector(options.images);

	}

	else if (window.NodeList && options.images instanceof window.NodeList) {

		imageNodes = options.images;

	} else if (window.Node && options.images instanceof window.Node) {

		imageNodes = [options.images];

	}

	if(typeof(options.bgnodes) == "string"){

	    bgnodes = selector(options.bgnodes);

	} else if (window.NodeList && options.elements instanceof window.NodeList) {

		bgnodes = options.bgnodes;

	} else if (window.Node && options.bgnodes instanceof window.Node) {

		bgnodes = [options.bgnodes];

	}

	preempted = true;

	for (i = 0, l = imageNodes.length; i < l; i++) images.push(imageNodes[i]);

	var holdercss = document.getElementById("holderjs-style");

	if (!holdercss) {

		holdercss = document.createElement("style");

		holdercss.setAttribute("id", "holderjs-style");

		holdercss.type = "text/css";

		document.getElementsByTagName("head")[0].appendChild(holdercss);

	}

	if (!options.nocss) {

	    if (holdercss.styleSheet) {

		    holdercss.styleSheet.cssText += options.stylesheet;

	    } else {

		    holdercss.appendChild(document.createTextNode(options.stylesheet));

	    }

	}

	var cssregex = new RegExp(options.domain + "\/(.*?)\"?\\)");

	for (var l = bgnodes.length, i = 0; i < l; i++) {

		var src = window.getComputedStyle(bgnodes[i], null)

			.getPropertyValue("background-image");

		var flags = src.match(cssregex);

		var bgsrc = bgnodes[i].getAttribute("data-background-src");

		if (flags) {

			var holder = parse_flags(flags[1].split("/"), options);

			if (holder) {

				render("background", bgnodes[i], holder, src);

			}

		}

		else if(bgsrc != null){

		    var holder = parse_flags(bgsrc.substr(bgsrc.lastIndexOf(options.domain) + options.domain.length + 1)

				.split("/"), options);

		    if(holder){

			render("background", bgnodes[i], holder, src);

		    }

		}

	}

	for (l = images.length, i = 0; i < l; i++) {

		var attr_src = attr_data_src = src = null;

		try{

		    attr_src = images[i].getAttribute("src");

		    attr_datasrc = images[i].getAttribute("data-src");

		}catch(e){}

		if (attr_datasrc == null && !! attr_src && attr_src.indexOf(options.domain) >= 0) {

			src = attr_src;

		} else if ( !! attr_datasrc && attr_datasrc.indexOf(options.domain) >= 0) {

			src = attr_datasrc;

		}

		if (src) {

			var holder = parse_flags(src.substr(src.lastIndexOf(options.domain) + options.domain.length + 1)

				.split("/"), options);

			if (holder) {

				if (holder.fluid) {

					render("fluid", images[i], holder, src)

				} else {

					render("image", images[i], holder, src);

				}

			}

		}

	}

	return app;

};

contentLoaded(win, function () {

	if (window.addEventListener) {

		window.addEventListener("resize", fluid_update, false);

		window.addEventListener("orientationchange", fluid_update, false);

	} else {

		window.attachEvent("onresize", fluid_update)

	}

	preempted || app.run();

});

if (typeof define === "function" && define.amd) {

	define("Holder", [], function () {

		return app;

	});

}

})(Holder, window);