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bower_components/bootstrap/docs/assets/js/holder/holder.js

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/*

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);