/*!
 * HeadJS     The only script in your <HEAD>    
 * Author     Tero Piirainen  (tipiirai)
 * Maintainer Robert Hoffmann (itechnology)
 * License    MIT / http://bit.ly/mit-license
 *
 * Version 0.99
 * http://headjs.com
 */
/* modify : head ==> Wind */
;
(function(win, undefined) {
	"use strict";

	var doc = win.document,
			domWaiters = [],
			queue = [], // waiters for the "head ready" event
			handlers = {}, // user functions waiting for events
			assets = {}, // loadable items in various states
			isAsync = "async" in doc.createElement("script") || "MozAppearance" in doc.documentElement.style || win.opera,
			isHeadReady,
			isDomReady,
			/*** public API ***/
			headVar = win.head_conf && win.head_conf.head || "Wind",
			api = win[headVar] = (win[headVar] || function() {
		api.ready.apply(null, arguments);
	}),
			// states
			PRELOADING = 1,
			PRELOADED = 2,
			LOADING = 3,
			LOADED = 4;

	// Method 1: simply load and let browser take care of ordering
	if (isAsync) {
		api.load = function() {
			///<summary>
			/// INFO: use cases
			///    head.load("http://domain.com/file.js","http://domain.com/file.js", callBack)
			///    head.load({ label1: "http://domain.com/file.js" }, { label2: "http://domain.com/file.js" }, callBack)
			///</summary> 
			var args = arguments,
					callback = args[args.length - 1],
					items = {};

			if (!isFunction(callback)) {
				callback = null;
			}

			each(args, function(item, i) {
				if (item !== callback) {
					item = getAsset(item);
					items[item.name] = item;

					load(item, callback && i === args.length - 2 ? function() {
						if (allLoaded(items)) {
							one(callback);
						}

					} : null);
				}
			});

			return api;
		};


		// Method 2: preload with text/cache hack
	} else {
		api.load = function() {
			var args = arguments,
					rest = [].slice.call(args, 1),
					next = rest[0];

			// wait for a while. immediate execution causes some browsers to ignore caching
			if (!isHeadReady) {
				queue.push(function() {
					api.load.apply(null, args);
				});

				return api;
			}

			// multiple arguments
			if (!!next) {
				/* Preload with text/cache hack (not good!)
				 * http://blog.getify.com/on-script-loaders/
				 * http://www.nczonline.net/blog/2010/12/21/thoughts-on-script-loaders/
				 * If caching is not configured correctly on the server, then items could load twice !
				 *************************************************************************************/
				each(rest, function(item) {
					if (!isFunction(item)) {
						preLoad(getAsset(item));
					}
				});

				// execute
				load(getAsset(args[0]), isFunction(next) ? next : function() {
					api.load.apply(null, rest);
				});
			}
			else {
				// single item
				load(getAsset(args[0]));
			}

			return api;
		};
	}

	// INFO: for retro compatibility
	api.js = api.load;

	api.test = function(test, success, failure, callback) {
		///<summary>
		/// INFO: use cases:
		///    head.test(condition, null       , "file.NOk" , callback);
		///    head.test(condition, "fileOk.js", null       , callback);        
		///    head.test(condition, "fileOk.js", "file.NOk" , callback);
		///    head.test(condition, "fileOk.js", ["file.NOk", "file.NOk"], callback);
		///    head.test({
		///               test    : condition,
		///               success : [{ label1: "file1Ok.js"  }, { label2: "file2Ok.js" }],
		///               failure : [{ label1: "file1NOk.js" }, { label2: "file2NOk.js" }],
		///               callback: callback
		///    );  
		///    head.test({
		///               test    : condition,
		///               success : ["file1Ok.js" , "file2Ok.js"],
		///               failure : ["file1NOk.js", "file2NOk.js"],
		///               callback: callback
		///    );         
		///</summary>    
		var obj = (typeof test === 'object') ? test : {
			test: test,
			success: !!success ? isArray(success) ? success : [success] : false,
			failure: !!failure ? isArray(failure) ? failure : [failure] : false,
			callback: callback || noop
		};

		// Test Passed ?
		var passed = !!obj.test;

		// Do we have a success case
		if (passed && !!obj.success) {
			obj.success.push(obj.callback);
			api.load.apply(null, obj.success);
		}
		// Do we have a fail case
		else if (!passed && !!obj.failure) {
			obj.failure.push(obj.callback);
			api.load.apply(null, obj.failure);
		}
		else {
			callback();
		}

		return api;
	};

	api.ready = function(key, callback) {
		///<summary>
		/// INFO: use cases:
		///    head.ready(callBack)
		///    head.ready(document , callBack)
		///    head.ready("file.js", callBack);
		///    head.ready("label"  , callBack);        
		///</summary>

		// DOM ready check: head.ready(document, function() { });
		if (key === doc) {
			if (isDomReady) {
				one(callback);
			}
			else {
				domWaiters.push(callback);
			}

			return api;
		}

		// shift arguments
		if (isFunction(key)) {
			callback = key;
			key = "ALL";
		}

		// make sure arguments are sane
		if (typeof key !== 'string' || !isFunction(callback)) {
			return api;
		}

		// This can also be called when we trigger events based on filenames & labels
		var asset = assets[key];

		// item already loaded --> execute and return
		if (asset && asset.state === LOADED || key === 'ALL' && allLoaded() && isDomReady) {
			one(callback);
			return api;
		}

		var arr = handlers[key];
		if (!arr) {
			arr = handlers[key] = [callback];
		}
		else {
			arr.push(callback);
		}

		return api;
	};


	// perform this when DOM is ready
	api.ready(doc, function() {

		if (allLoaded()) {
			each(handlers.ALL, function(callback) {
				one(callback);
			});
		}

		if (api.feature) {
			api.feature("domloaded", true);
		}
	});


	/* private functions
	 *********************/
	function noop() {
		// does nothing
	}

	function each(arr, callback) {
		if (!arr) {
			return;
		}

		// arguments special type
		if (typeof arr === 'object') {
			arr = [].slice.call(arr);
		}

		// do the job
		for (var i = 0, l = arr.length; i < l; i++) {
			callback.call(arr, arr[i], i);
		}
	}

	/* A must read: http://bonsaiden.github.com/JavaScript-Garden
	 ************************************************************/
	function is(type, obj) {
		var clas = Object.prototype.toString.call(obj).slice(8, -1);
		return obj !== undefined && obj !== null && clas === type;
	}

	function isFunction(item) {
		return is("Function", item);
	}

	function isArray(item) {
		return is("Array", item);
	}

	function toLabel(url) {
		///<summary>Converts a url to a file label</summary>
		var items = url.split("/"),
				name = items[items.length - 1],
				i = name.indexOf("?");

		return i !== -1 ? name.substring(0, i) : name;
	}

	// INFO: this look like a "im triggering callbacks all over the place, but only wanna run it one time function" ..should try to make everything work without it if possible
	// INFO: Even better. Look into promises/defered's like jQuery is doing
	function one(callback) {
		///<summary>Execute a callback only once</summary>
		callback = callback || noop;

		if (callback._done) {
			return;
		}

		callback();
		callback._done = 1;
	}

	function getAsset(item) {
		///<summary>
		/// Assets are in the form of
		/// { 
		///     name : label,
		///     url  : url,
		///     state: state
		/// }
		///</summary>
		var asset = {};

		if (typeof item === 'object') {
			for (var label in item) {
				if (!!item[label]) {
					asset = {
						name: label,
						url: item[label]
					};
				}
			}
		}
		else {
			asset = {
				name: toLabel(item),
				url: item
			};
		}

		// is the item already existant
		var existing = assets[asset.name];
		if (existing && existing.url === asset.url) {
			return existing;
		}

		assets[asset.name] = asset;
		return asset;
	}

	function allLoaded(items) {
		items = items || assets;

		for (var name in items) {
			if (items.hasOwnProperty(name) && items[name].state !== LOADED) {
				return false;
			}
		}

		return true;
	}


	function onPreload(asset) {
		asset.state = PRELOADED;

		each(asset.onpreload, function(afterPreload) {
			afterPreload.call();
		});
	}

	function preLoad(asset, callback) {
		if (asset.state === undefined) {

			asset.state = PRELOADING;
			asset.onpreload = [];

			loadAsset({url: asset.url, type: 'cache'}, function() {
				onPreload(asset);
			});
		}
	}

	function load(asset, callback) {
		///<summary>Used with normal loading logic</summary>
		callback = callback || noop;

		if (asset.state === LOADED) {
			callback();
			return;
		}

		// INFO: why would we trigger a ready event when its not really loaded yet ?
		if (asset.state === LOADING) {
			api.ready(asset.name, callback);
			return;
		}

		if (asset.state === PRELOADING) {
			asset.onpreload.push(function() {
				load(asset, callback);
			});
			return;
		}

		asset.state = LOADING;

		loadAsset(asset, function() {
			asset.state = LOADED;
			callback();

			// handlers for this asset
			each(handlers[asset.name], function(fn) {
				one(fn);
			});

			// dom is ready & no assets are queued for loading
			// INFO: shouldn't we be doing the same test above ?
			if (isDomReady && allLoaded()) {
				each(handlers.ALL, function(fn) {
					one(fn);
				});
			}
		});
	}

	/* Parts inspired from: https://github.com/cujojs/curl
	 ******************************************************/
	function loadAsset(asset, callback) {
		callback = callback || noop;

		var ele;
		if (/\.css[^\.]*$/.test(asset.url)) {
			ele = doc.createElement('link');
			ele.type = 'text/' + (asset.type || 'css');
			ele.rel = 'stylesheet';
			ele.href = asset.url;
		}
		else {
			ele = doc.createElement('script');
			ele.type = 'text/' + (asset.type || 'javascript');
			ele.src = asset.url;
		}

		ele.onload = ele.onreadystatechange = process;
		ele.onerror = error;

		/* Good read, but doesn't give much hope !
		 * http://blog.getify.com/on-script-loaders/
		 * http://www.nczonline.net/blog/2010/12/21/thoughts-on-script-loaders/
		 * https://hacks.mozilla.org/2009/06/defer/
		 */

		// ASYNC: load in parellel and execute as soon as possible
		ele.async = false;
		// DEFER: load in parallel but maintain execution order
		ele.defer = false;

		function error(event) {
			event = event || win.event;

			// need some more detailed error handling here

			// release event listeners
			ele.onload = ele.onreadystatechange = ele.onerror = null;

			// do callback
			callback();
		}

		function process(event) {
			event = event || win.event;

			// IE 7/8 (2 events on 1st load)
			// 1) event.type = readystatechange, s.readyState = loading
			// 2) event.type = readystatechange, s.readyState = loaded

			// IE 7/8 (1 event on reload)
			// 1) event.type = readystatechange, s.readyState = complete 

			// event.type === 'readystatechange' && /loaded|complete/.test(s.readyState)

			// IE 9 (3 events on 1st load)
			// 1) event.type = readystatechange, s.readyState = loading
			// 2) event.type = readystatechange, s.readyState = loaded
			// 3) event.type = load            , s.readyState = loaded

			// IE 9 (2 events on reload)
			// 1) event.type = readystatechange, s.readyState = complete 
			// 2) event.type = load            , s.readyState = complete 

			// event.type === 'load'             && /loaded|complete/.test(s.readyState)
			// event.type === 'readystatechange' && /loaded|complete/.test(s.readyState)

			// IE 10 (3 events on 1st load)
			// 1) event.type = readystatechange, s.readyState = loading
			// 2) event.type = load            , s.readyState = complete
			// 3) event.type = readystatechange, s.readyState = loaded

			// IE 10 (3 events on reload)
			// 1) event.type = readystatechange, s.readyState = loaded
			// 2) event.type = load            , s.readyState = complete
			// 3) event.type = readystatechange, s.readyState = complete 

			// event.type === 'load'             && /loaded|complete/.test(s.readyState)
			// event.type === 'readystatechange' && /complete/.test(s.readyState)

			// Other Browsers (1 event on 1st load)
			// 1) event.type = load, s.readyState = undefined

			// Other Browsers (1 event on reload)
			// 1) event.type = load, s.readyState = undefined            

			// event.type == 'load' && s.readyState = undefined


			// !doc.documentMode is for IE6/7, IE8+ have documentMode
			if (event.type === 'load' || (/loaded|complete/.test(ele.readyState) && (!doc.documentMode || doc.documentMode < 9))) {
				// release event listeners               
				ele.onload = ele.onreadystatechange = ele.onerror = null;

				// do callback
				callback();
			}

			// emulates error on browsers that don't create an exception
			// INFO: timeout not clearing ..why ?
			//asset.timeout = win.setTimeout(function () {
			//    error({ type: "timeout" });
			//}, 3000);
		}

		// use insertBefore to keep IE from throwing Operation Aborted (thx Bryan Forbes!)
		var head = doc['head'] || doc.getElementsByTagName('head')[0];
		// but insert at end of head, because otherwise if it is a stylesheet, it will not ovverride values
		head.insertBefore(ele, head.lastChild);
	}

	/* Mix of stuff from jQuery & IEContentLoaded
	 * http://dev.w3.org/html5/spec/the-end.html#the-end
	 ***************************************************/
	function domReady() {
		// Make sure body exists, at least, in case IE gets a little overzealous (jQuery ticket #5443).
		if (!doc.body) {
			// let's not get nasty by setting a timeout too small.. (loop mania guaranteed if assets are queued)
			win.clearTimeout(api.readyTimeout);
			api.readyTimeout = win.setTimeout(domReady, 50);
			return;
		}

		if (!isDomReady) {
			isDomReady = true;
			each(domWaiters, function(fn) {
				one(fn);
			});
		}
	}

	function domContentLoaded() {
		// W3C
		if (doc.addEventListener) {
			doc.removeEventListener("DOMContentLoaded", domContentLoaded, false);
			domReady();
		}

		// IE
		else if (doc.readyState === "complete") {
			// we're here because readyState === "complete" in oldIE
			// which is good enough for us to call the dom ready!            
			doc.detachEvent("onreadystatechange", domContentLoaded);
			domReady();
		}
	}
	;

	// Catch cases where ready() is called after the browser event has already occurred.
	// we once tried to use readyState "interactive" here, but it caused issues like the one
	// discovered by ChrisS here: http://bugs.jquery.com/ticket/12282#comment:15    
	if (doc.readyState === "complete") {
		domReady();
	}

	// W3C
	else if (doc.addEventListener) {
		doc.addEventListener("DOMContentLoaded", domContentLoaded, false);

		// A fallback to window.onload, that will always work
		win.addEventListener("load", domReady, false);
	}

	// IE
	else {
		// Ensure firing before onload, maybe late but safe also for iframes
		doc.attachEvent("onreadystatechange", domContentLoaded);

		// A fallback to window.onload, that will always work
		win.attachEvent("onload", domReady);

		// If IE and not a frame
		// continually check to see if the document is ready
		var top = false;

		try {
			top = win.frameElement == null && doc.documentElement;
		} catch (e) {
		}

		if (top && top.doScroll) {
			(function doScrollCheck() {
				if (!isDomReady) {
					try {
						// Use the trick by Diego Perini
						// http://javascript.nwbox.com/IEContentLoaded/
						top.doScroll("left");
					} catch (error) {
						// let's not get nasty by setting a timeout too small.. (loop mania guaranteed if assets are queued)
						win.clearTimeout(api.readyTimeout);
						api.readyTimeout = win.setTimeout(doScrollCheck, 50);
						return;
					}

					// and execute any waiting functions
					domReady();
				}
			})();
		}
	}

	/*
	 We wait for 300 ms before asset loading starts. for some reason this is needed
	 to make sure assets are cached. Not sure why this happens yet. A case study:
	 
	 https://github.com/headjs/headjs/issues/closed#issue/83
	 */
	setTimeout(function() {
		isHeadReady = true;
		each(queue, function(fn) {
			fn();
		});

	}, 300);

	// browser type & version
	var ua = navigator.userAgent.toLowerCase();

	ua = /(webkit)[ \/]([\w.]+)/.exec(ua) ||
			/(opera)(?:.*version)?[ \/]([\w.]+)/.exec(ua) ||
			/(msie) ([\w.]+)/.exec(ua) ||
			!/compatible/.test(ua) && /(mozilla)(?:.*? rv:([\w.]+))?/.exec(ua) || [];


	if (ua[1] == 'msie') {
		ua[1] = 'ie';
		ua[2] = document.documentMode || ua[2];
	}

	api.browser = {version: ua[2]};
	api.browser[ua[1]] = true;

	// IE specific
	if (api.browser.ie) {
		// HTML5 support
		each("abbr|article|aside|audio|canvas|details|figcaption|figure|footer|header|hgroup|mark|meter|nav|output|progress|section|summary|time|video".split("|"), function(el) {
			doc.createElement(el);
		});
	}

})(window);

/*
 * 防止浏览器不支持console报错
 */
if (!window.console) {
	window.console = {};
	var funs = ["profiles", "memory", "_commandLineAPI", "debug", "error", "info", "log", "warn", "dir", "dirxml", "trace", "assert", "count", "markTimeline", "profile", "profileEnd", "time", "timeEnd", "timeStamp", "group", "groupCollapsed", "groupEnd"];
	for (var i = 0; i < funs.length; i++) {
		console[funs[i]] = function() {
		};
	}
}

/*
 *解决ie6下不支持背景缓存
 */
Wind.ready(function() {
	if (!+'\v1' && !('maxHeight' in document.body.style)) {
		try {
			document.execCommand("BackgroundImageCache", false, true);
		} catch (e) {
		}
	}
});

