/*jquery.cascade.js */
/*
 * jQuery UI cascade
 * version: 1.1.1 (6/16/2008)
 * @requires: jQuery v1.2 or later
 * adapted from Yehuda Katz, Rein Henrichs autocomplete plugin
 * Dual licensed under the MIT and GPL licenses:
 *   http://www.opensource.org/licenses/mit-license.php
 *   http://www.gnu.org/licenses/gpl.html
 *
 * Copyright 2008 Mike Nichols
   	
 */

;(function($) {
	$.ui = $.ui || {}; $.ui.cascade = $.ui.cascade || {}; 

	$.fn.cascade = function(parent, opt) {
		if( opt.event ) {
			//namespace our event 
			opt.event = opt.event.replace('.cascade','') + '.cascade';
		}

		opt = $.extend({}, {
			list: [], //static list to use as datasource 
			timeout: 10,//delay before firing getList operation
			getList: function(select) { $(this).trigger("updateList", [opt.list]); }, //function to fetch datasource
			template: function(str) { return "<option value='" + str + "'>" + str + "</option>"; },//applied to each item in datasource      
			match: function(selectedValue) { return true;}, //'this' is the js object, or the current list item from 'getList',
			event: "change.cascade",	//event to listen on parent which fires the cascade
			getParentValue: function(parent) { return $(parent).val(); } //delegate for retrieving the parent element's value
		}, opt);

		if($.ui.cascade.ext) {
			for(var ext in $.ui.cascade.ext) {
				if(opt[ext]) {
					opt = $.extend(opt, $.ui.cascade.ext[ext](opt));
					delete opt[ext];
				}
			}
		}

		return this.each(function() {
			var source = $(parent);
			var self = $(this);

			//bind any events in extensions to each instance
			if($.ui.cascade.event) {
				for(var e in $.ui.cascade.event) {
					self.bind(e + ".cascade",[source],$.ui.cascade.event[e]);
				}
			}

			$(source).bind(opt.event,function() {
				self.trigger("loading.cascade",[source[0]]);

				var selectTimeout = $.data(self, "selectTimeout");
				if(selectTimeout) { window.clearInterval(selectTimeout); }
				$.data(self, "selectTimeout", window.setTimeout(function() {
					self.trigger("cascade"); 
				}, opt.timeout));
			});

			self.bind("cascade", function() {
				self.one("updateList", function(e, list) {
					list = $(list)
						.filter(function() { return opt.match.call(this, opt.getParentValue(parent)); })
						.map(function() { 
							var node = $(opt.template(this))[0];
							return node;
						});

					self.empty(); //clear the source/select

					if (list.length) {
						self.html(list);
					}

					self.trigger("loaded.cascade",[source[0]]);//be sure to fire even if there is no data

					if( self.is(":input") ) {
						self.trigger("change.cascade");
					}
				});
				opt.getList.call(self[0],source);	//call with child element as this
			});
		});
	};
})(jQuery);