/* jQuery Session vars v.0.3
 * by Jay Salvat
 * http://www.jaysalvat.com
 * -----------------------------------------------
 * Inspired by an idea from Mario Heiderich
 * http://code.google.com/p/quipt/
 * -----------------------------------------------
 * Requires jquery.json.js by DeadWisdom
 * http://code.google.com/p/jquery-json/
 * -----------------------------------------------
 * CHANGELOG
 * 0.3 -- 11-JUL-08
 * Security improvements
 * Calling manually sessionStart and sessionStop is not required anymore
 * Window.name is keept between pages
 * 0.2 -- 10-JUL-08
 * Now works with functions, objects and arrays
 * 0.1 -- 08-JUL-08
 * First draft
 * -----------------------------------------------
 * USAGE
 * - To Store
 * $(function() {
 * 	$.session("myVar, "value");
 * });
 * 
 * - To Read
 * $(function() {
 * 	alert( $.session("myVar) ); 	
 * });
*/
(function($) {
		var sessionData = {};
		var windowName 	= "";
		var domain 			= location.href.match(/\w+:\/\/[^\/]+/)[0];
		var referrer 		= (document.referrer) ? document.referrer.match(/\w+:\/\/[^\/]+/)[0] : "";

		if(referrer == "" || referrer !== domain) {
			window.name = window.name.replace("#"+domain+"#", "");
		}
			
		function loadData() {
			stored = window.name.split("#"+domain+"#");
			windowName = window.name = stored[0];
			if (data = stored[1]) {	
				$.each(data.split(";"), function(i, data) {
							parts 		= data.split("=");
							varName 	= parts[0];
							varValue 	= unescape(parts[1]);
							sessionData[varName] = varValue;
				});
			}
		}
		
		function saveData() {
			var dataToStore = windowName+"#"+domain+"#";
			$.each(sessionData, function(varName, varValue) {		
					if (varName && varValue) {
						dataToStore += ( varName + "=" + escape( varValue ) + ";" );
					}
			});
			window.name = dataToStore;
		}
		
		$.session = function(name, value) {
			if (value) {
				if ($.isFunction(value)) {
						value = value();
				}
				if ( $.toJSON ) {
					sessionData[name] = $.toJSON(value);
				} else {
					sessionData[name] = value;
				}
			} else {
				if ( $.evalJSON ) {
					return $.evalJSON(sessionData[name]);
				} else {
					return sessionData[name];
				}
			}
		}
		
		$.sessionStop = function() {
			saveData();
		}		
		
		$.sessionStart = function() {
			loadData();
 		}

		$.sessionStart();
		window.onunload = function() { $.sessionStop(); };
		
	})(jQuery);

