/*! Copyright (c) 2010 Brandon Aaron (http://brandonaaron.net)
* Dual licensed under the MIT (MIT_LICENSE.txt)
* and GPL Version 2 (GPL_LICENSE.txt) licenses.
*
* Version: 1.1.1
* Requires jQuery 1.3+
* Docs: http://docs.jquery.com/Plugins/livequery
*/

(function ($)
{

	$.extend($.fn, {
		livequery: function (type, fn, fn2)
		{
			var self = this, q;

			// Handle different call patterns
			if ($.isFunction(type))
				fn2 = fn, fn = type, type = undefined;

			// See if Live Query already exists
			$.each($.livequery.queries, function (i, query)
			{
				if (self.selector == query.selector && self.context == query.context &&
				type == query.type && (!fn || fn.$lqguid == query.fn.$lqguid) && (!fn2 || fn2.$lqguid == query.fn2.$lqguid))
				// Found the query, exit the each loop
					return (q = query) && false;
			});

			// Create new Live Query if it wasn't found
			q = q || new $.livequery(this.selector, this.context, type, fn, fn2);

			// Make sure it is running
			q.stopped = false;

			// Run it immediately for the first time
			q.run();

			// Contnue the chain
			return this;
		},

		expire: function (type, fn, fn2)
		{
			var self = this;

			// Handle different call patterns
			if ($.isFunction(type))
				fn2 = fn, fn = type, type = undefined;

			// Find the Live Query based on arguments and stop it
			$.each($.livequery.queries, function (i, query)
			{
				if (self.selector == query.selector && self.context == query.context &&
				(!type || type == query.type) && (!fn || fn.$lqguid == query.fn.$lqguid) && (!fn2 || fn2.$lqguid == query.fn2.$lqguid) && !this.stopped)
					$.livequery.stop(query.id);
			});

			// Continue the chain
			return this;
		}
	});

	$.livequery = function (selector, context, type, fn, fn2)
	{
		this.selector = selector;
		this.context = context;
		this.type = type;
		this.fn = fn;
		this.fn2 = fn2;
		this.elements = [];
		this.stopped = false;

		// The id is the index of the Live Query in $.livequery.queries
		this.id = $.livequery.queries.push(this) - 1;

		// Mark the functions for matching later on
		fn.$lqguid = fn.$lqguid || $.livequery.guid++;
		if (fn2) fn2.$lqguid = fn2.$lqguid || $.livequery.guid++;

		// Return the Live Query
		return this;
	};

	$.livequery.prototype = {
		stop: function ()
		{
			var query = this;

			if (this.type)
			// Unbind all bound events
				this.elements.unbind(this.type, this.fn);
			else if (this.fn2)
			// Call the second function for all matched elements
				this.elements.each(function (i, el)
				{
					query.fn2.apply(el);
				});

			// Clear out matched elements
			this.elements = [];

			// Stop the Live Query from running until restarted
			this.stopped = true;
		},

		run: function ()
		{
			// Short-circuit if stopped
			if (this.stopped) return;
			var query = this;

			var oEls = this.elements,
			els = $(this.selector, this.context),
			nEls = els.not(oEls);

			// Set elements to the latest set of matched elements
			this.elements = els;

			if (this.type)
			{
				// Bind events to newly matched elements
				nEls.bind(this.type, this.fn);

				// Unbind events to elements no longer matched
				if (oEls.length > 0)
					$.each(oEls, function (i, el)
					{
						if ($.inArray(el, els) < 0)
							$.event.remove(el, query.type, query.fn);
					});
			}
			else
			{
				// Call the first function for newly matched elements
				nEls.each(function ()
				{
					query.fn.apply(this);
				});

				// Call the second function for elements no longer matched
				if (this.fn2 && oEls.length > 0)
					$.each(oEls, function (i, el)
					{
						if ($.inArray(el, els) < 0)
							query.fn2.apply(el);
					});
			}
		}
	};

	$.extend($.livequery, {
		guid: 0,
		queries: [],
		queue: [],
		running: false,
		timeout: null,

		checkQueue: function ()
		{
			if ($.livequery.running && $.livequery.queue.length)
			{
				var length = $.livequery.queue.length;
				// Run each Live Query currently in the queue
				while (length--)
					$.livequery.queries[$.livequery.queue.shift()].run();
			}
		},

		pause: function ()
		{
			// Don't run anymore Live Queries until restarted
			$.livequery.running = false;
		},

		play: function ()
		{
			// Restart Live Queries
			$.livequery.running = true;
			// Request a run of the Live Queries
			$.livequery.run();
		},

		registerPlugin: function ()
		{
			$.each(arguments, function (i, n)
			{
				// Short-circuit if the method doesn't exist
				if (!$.fn[n]) return;

				// Save a reference to the original method
				var old = $.fn[n];

				// Create a new method
				$.fn[n] = function ()
				{
					// Call the original method
					var r = old.apply(this, arguments);

					// Request a run of the Live Queries
					$.livequery.run();

					// Return the original methods result
					return r;
				}
			});
		},

		run: function (id)
		{
			if (id != undefined)
			{
				// Put the particular Live Query in the queue if it doesn't already exist
				if ($.inArray(id, $.livequery.queue) < 0)
					$.livequery.queue.push(id);
			}
			else
			// Put each Live Query in the queue if it doesn't already exist
				$.each($.livequery.queries, function (id)
				{
					if ($.inArray(id, $.livequery.queue) < 0)
						$.livequery.queue.push(id);
				});

			// Clear timeout if it already exists
			if ($.livequery.timeout) clearTimeout($.livequery.timeout);
			// Create a timeout to check the queue and actually run the Live Queries
			$.livequery.timeout = setTimeout($.livequery.checkQueue, 20);
		},

		stop: function (id)
		{
			if (id != undefined)
			// Stop are particular Live Query
				$.livequery.queries[id].stop();
			else
			// Stop all Live Queries
				$.each($.livequery.queries, function (id)
				{
					$.livequery.queries[id].stop();
				});
		}
	});

	// Register core DOM manipulation methods
	$.livequery.registerPlugin('append', 'prepend', 'after', 'before', 'wrap', 'attr', 'removeAttr', 'addClass', 'removeClass', 'toggleClass', 'empty', 'remove', 'html');

	// Run Live Queries when the Document is ready
	$(function () { $.livequery.play(); });

})(jQuery);