/*
Holder - 1.9 - 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) {
var dimension_arr = [height, width].sort();
var maxFactor = Math.round(dimension_arr[1] / 16),
minFactor = Math.round(dimension_arr[0] / 16);
var text_height = Math.max(template.size, maxFactor);
return {
height: text_height
}
}
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 : (dimensions.width + "x" + dimensions.height);
if (ctx.measureText(text).width / width > 1) {
text_height = template.size / (ctx.measureText(text).width / 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);
var ratio = 1;
if(window.devicePixelRatio && window.devicePixelRatio > 1){
ratio = window.devicePixelRatio;
}
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 (!fallback) {
el.style.backgroundImage = "url(" + draw(ctx, dimensions, theme, ratio) + ")";
el.style.backgroundSize = dimensions.width+"px "+dimensions.height+"px";
}
}
};
function fluid(el, holder, src) {
var dimensions = holder.dimensions,
theme = holder.theme,
text = holder.text;
var dimensions_caption = dimensions.width + "x" + dimensions.height;
theme = (text ? extend(theme, {
text: text
}) : theme);
var fluid = document.createElement("div");
fluid.style.backgroundColor = theme.background;
fluid.style.color = theme.foreground;
fluid.className = el.className + " holderjs-fluid";
fluid.style.width = holder.dimensions.width + (holder.dimensions.width.indexOf("%")>0?"":"px");
fluid.style.height = holder.dimensions.height + (holder.dimensions.height.indexOf("%")>0?"":"px");
fluid.id = el.id;
el.style.width=0;
el.style.height=0;
if (theme.text) {
fluid.appendChild(document.createTextNode(theme.text))
} else {
fluid.appendChild(document.createTextNode(dimensions_caption))
fluid_images.push(fluid);
setTimeout(fluid_update, 0);
}
el.parentNode.insertBefore(fluid, el.nextSibling)
if(window.jQuery){
jQuery(function($){
$(el).on("load", function(){
el.style.width = fluid.style.width;
el.style.height = fluid.style.height;
$(el).show();
$(fluid).remove();
});
})
}
}
function fluid_update() {
for (i in fluid_images) {
if(!fluid_images.hasOwnProperty(i)) continue;
var el = fluid_images[i],
label = el.firstChild;
el.style.lineHeight = el.offsetHeight+"px";
label.data = el.offsetWidth + "x" + el.offsetHeight;
}
}
function parse_flags(flags, options) {
var ret = {
theme: settings.themes.gray
}, render = false;
for (sl = flags.length, j = 0; j < sl; j++) {
var flag = flags[j];
if (app.flags.dimensions.match(flag)) {
render = true;
ret.dimensions = app.flags.dimensions.output(flag);
} else if (app.flags.fluid.match(flag)) {
render = true;
ret.dimensions = app.flags.fluid.output(flag);
ret.fluid = true;
} else if (app.flags.colors.match(flag)) {
ret.theme = app.flags.colors.output(flag);
} else if (options.themes[flag]) {
//If a theme is specified, it will override custom colors
ret.theme = options.themes[flag];
} else if (app.flags.text.match(flag)) {
ret.text = app.flags.text.output(flag);
} else if(app.flags.font.match(flag)){
ret.font = app.flags.font.output(flag);
}
else if(app.flags.auto.match(flag)){
ret.auto = true;
}
}
return render ? ret : false;
};
if (!canvas.getContext) {
fallback = true;
} else {
if (canvas.toDataURL("image/png")
.indexOf("data:image/png") < 0) {
//Android doesn't support data URI
fallback = true;
} else {
var ctx = canvas.getContext("2d");
}
}
var fluid_images = [];
var settings = {
domain: "holder.js",
images: "img",
bgnodes: ".holderjs",
themes: {
"gray": {
background: "#eee",
foreground: "#aaa",
size: 12
},
"social": {
background: "#3a5a97",
foreground: "#fff",
size: 12
},
"industrial": {
background: "#434A52",
foreground: "#C2F200",
size: 12
}
},
stylesheet: ".holderjs-fluid {font-size:16px;font-weight:bold;text-align:center;font-family:sans-serif;margin:0}"
};
app.flags = {
dimensions: {
regex: /^(\d+)x(\d+)$/,
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 = [];
if(options.images instanceof window.NodeList){
imageNodes = options.images;
}
else if(options.images instanceof window.Node){
imageNodes = [options.images];
}
else{
imageNodes = selector(options.images);
}
if(options.elements instanceof window.NodeList){
bgnodes = options.bgnodes;
}
else if(options.bgnodes instanceof window.Node){
bgnodes = [options.bgnodes];
}
else{
bgnodes = selector(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(holdercss.styleSheet){
holdercss.styleSheet += options.stylesheet;
}
else{
holdercss.textContent+= 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);
if (flags) {
var holder = parse_flags(flags[1].split("/"), options);
if (holder) {
render("background", bgnodes[i], holder, src);
}
}
}
for (var l = images.length, i = 0; i < l; i++) {
var src = images[i].getAttribute("src") || images[i].getAttribute("data-src");
if (src != null && src.indexOf(options.domain) >= 0) {
var holder = parse_flags(src.substr(src.lastIndexOf(options.domain) + options.domain.length + 1)
.split("/"), options);
if (holder) {
if (holder.fluid) {
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);
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