/**
 * Ajax Queue Plugin
 * Homepage: http://jquery.com/plugins/project/ajaxqueue
 * Documentation: http://docs.jquery.com/AjaxQueue
 *
 * Queued Ajax requests.
 * A new Ajax request won't be started until the previous queued 
 * request has finished.
 *
 * Synced Ajax requests.
 * The Ajax request will happen as soon as you call this method, but
 * the callbacks (success/error/complete) won't fire until all previous
 * synced requests have been completed.
 */
(function($){
	var ajax = $.ajax;
	var pendingRequests = {};
	var synced = [];
	var syncedData = [];
	$.ajax = function(settings){
		// create settings for compatibility with ajaxSetup
		settings = jQuery.extend(settings, jQuery.extend({}, jQuery.ajaxSettings, settings));
		var port = settings.port;
		switch(settings.mode){
		case "abort":
			if(pendingRequests[port]){
				pendingRequests[port].abort();
			}
			return pendingRequests[port] = ajax.apply(this, arguments);
		case "queue":
			var _old = settings.complete;
			settings.complete = function(){
				if(_old)
					_old.apply( this, arguments );
				jQuery([ajax]).dequeue("ajax" + port );;
			};
		jQuery([ ajax ]).queue("ajax" + port, function(){
				ajax( settings );
			});
			return;
		case "sync":
			var pos = synced.length;
			synced[ pos ] = {
				error: settings.error,
				success: settings.success,
				complete: settings.complete,
				done: false
			};
			syncedData[ pos ] = {
				error: [],
				success: [],
				complete: []
			};
			settings.error = function(){ syncedData[ pos ].error = arguments; };
			settings.success = function(){ syncedData[ pos ].success = arguments; };
			settings.complete = function(){
				syncedData[ pos ].complete = arguments;
				synced[ pos ].done = true;
			if( pos == 0 || !synced[ pos-1 ])
					for( var i = pos; i < synced.length && synced[i].done; i++ ){
						if ( synced[i].error ) synced[i].error.apply( jQuery, syncedData[i].error );
						if ( synced[i].success ) synced[i].success.apply( jQuery, syncedData[i].success );
						if ( synced[i].complete ) synced[i].complete.apply( jQuery, syncedData[i].complete );
						synced[i] = null;
						syncedData[i] = null;
					}
			};
		}
		return ajax.apply(this, arguments);
	};
})(jQuery);