/** Head JS The only script in your Copyright Tero Piirainen (tipiirai) License MIT / http://bit.ly/mit-license http://headjs.com */ (function(doc) { var head = doc.documentElement, ie = navigator.userAgent.toLowerCase().indexOf("msie") != -1, ready = false, // is HEAD "ready" queue = [], // if not -> defer execution handlers = {}, // user functions waiting for events scripts = {}; // loadable scripts in different states /*** public API ***/ var head_var = window.head_conf && head_conf.head || "head", api = window[head_var] = (window[head_var] || function() { api.ready.apply(null, arguments); }); api.js = function() { var args = arguments, rest = [].slice.call(args, 1), next = rest[0]; if (!ready) { queue.push(function() { api.js.apply(null, args); }); return api; } // multiple arguments if (next) { // preload the rest if (!isFunc(next)) { each(rest, function(el) { if (!isFunc(el)) { preload(getScript(el)); } }); } // load all recursively in order load(getScript(args[0]), isFunc(next) ? next : function() { api.js.apply(null, rest); }); // single script } else { load(getScript(args[0])); } return api; }; api.ready = function(key, fn) { var script = scripts[key]; if (script && script.state == 'loaded') { fn.call(); return api; } // shift arguments if (isFunc(key)) { fn = key; key = "ALL"; } var arr = handlers[key]; if (!arr) { arr = handlers[key] = [fn]; } else { arr.push(fn); } return api; }; /* api.dump = function() { console.dir(scripts); }; */ /*** private functions ***/ function getScript(url) { var script = scripts[url.name || url]; if (script) { return script; } if (typeof url == 'object') { for (var key in url) { if (url[key]) { script = { name: key, url: url[key] }; } } } else { var els = url.split("/"), name = els[els.length -1], i = name.indexOf("?"); script = { name: i != -1 ? name.substring(0, i) : name, url: url }; } scripts[script.name] = script; return script; } function each(arr, fn) { if (!arr) { return; } // arguments special type if (typeof arr == 'object') { arr = [].slice.call(arr); } // do the job for (var i = 0; i < arr.length; i++) { fn.call(arr, arr[i], i); } } function isFunc(el) { return Object.prototype.toString.call(el) == '[object Function]'; } function onPreload(script) { script.state = "preloaded"; each(script.onpreload, function(el) { el.call(); }); } function preload(script, callback) { if (!script.state) { script.state = "preloading"; script.onpreload = []; /* Browser detection required. Firefox does not support script.type = text/cache http://www.phpied.com/preload-cssjavascript-without-execution/ */ if (/Firefox/.test(navigator.userAgent)) { var obj = doc.createElement('object'); obj.data = script.url; obj.width = 0; obj.height = 0; obj.onload = function() { onPreload(script); // avoid spinning progress indicator with setTimeout setTimeout(function() { head.removeChild(obj); }, 1); }; head.appendChild(obj); } else { scriptTag({ src: script.url, type: 'cache'}, function() { onPreload(script); }); } } } function load(script, callback) { if (script.state == 'loaded') { return callback(); } if (script.state == 'preloading') { return script.onpreload.push(function() { load(script, callback); }); } script.state = 'loading'; scriptTag(script.url, function() { script.state = 'loaded'; if (callback) { callback.call(); } // handlers for this script each(handlers[script.name], function(fn) { fn.call(); }); // TODO: do not run until DOM is loaded var allLoaded = true; for (var name in scripts) { if (scripts[name].state != 'loaded') { allLoaded = false; } } if (allLoaded) { each(handlers.ALL, function(fn) { if (!fn.done) { fn.call(); } fn.done = true; }); } }); } // if callback == true --> preload function scriptTag(src, callback) { var elem = doc.createElement('script'); elem.type = 'text/' + (src.type || 'javascript'); elem.src = src.src || src; elem.onreadystatechange = elem.onload = function() { var state = elem.readyState; if (!callback.done && (!state || /loaded|complete/.test(state))) { callback.call(); callback.done = true; } // cleanup. IE runs into trouble if (!ie) { head.removeChild(elem); } }; head.appendChild(elem); } /* Start after a small delay: guessing that the the head tag needs to be closed */ setTimeout(function() { ready = true; each(queue, function(fn) { fn.call(); }); }, 200); })(document);