jQuery.extend({
	historyCurrentHash: undefined,
	historyCallback: undefined,
	historyIframeSrc: undefined,
	historyNeedIframe: jQuery.browser.msie && (jQuery.browser.version < 8 || document.documentMode < 8),
	
	historyInit: function(callback, src){
		jQuery.historyCallback = callback;
		if (src) jQuery.historyIframeSrc = src;
		var current_hash = location.hash.replace(/\?.*$/, '');
		
		jQuery.historyCurrentHash = current_hash;
		if (jQuery.historyNeedIframe) {
			// To stop the callback firing twice during initilization if no hash present
			if (jQuery.historyCurrentHash == '') {
				jQuery.historyCurrentHash = '#';
			}
		
			// add hidden iframe for IE
			jQuery("body").prepend('<iframe id="jQuery_history" style="display: none;"'+
				' src="javascript:false;"></iframe>'
			);
			var ihistory = jQuery("#jQuery_history")[0];
			var iframe = ihistory.contentWindow.document;
			iframe.open();
			iframe.close();
			iframe.location.hash = current_hash;
		}
		else if (jQuery.browser.safari) {
			// etablish back/forward stacks
			jQuery.historyBackStack = [];
			jQuery.historyBackStack.length = history.length;
			jQuery.historyForwardStack = [];
			jQuery.lastHistoryLength = history.length;
			
			jQuery.isFirst = true;
		}
		if(current_hash){
			//jQuery.historyCallback(current_hash.replace(/^#/, ''));
			current_hash = current_hash.split('&');
			var action = current_hash[0];
			var callback = current_hash[1];
			var params = current_hash[2];
			if (action != null && callback != null){
				action = action.replace(/^#/, '');
				jQuery.historyCallback(action, eval(callback), params);
			}
		}
		setInterval(jQuery.historyCheck, 100);
	},
	
	historyAddHistory: function(hash) {
		// This makes the looping function do something
		jQuery.historyBackStack.push(hash);
		
		jQuery.historyForwardStack.length = 0; // clear forwardStack (true click occured)
		this.isFirst = true;
	},
	
	historyCheck: function(){
		if (jQuery.historyNeedIframe) {
			// On IE, check for location.hash of iframe
			var ihistory = jQuery("#jQuery_history")[0];
			var iframe = ihistory.contentDocument || ihistory.contentWindow.document;
			var current_hash = iframe.location.hash.replace(/\?.*$/, '');
			if(current_hash != jQuery.historyCurrentHash) {
				location.hash = current_hash;
				jQuery.historyCurrentHash = current_hash;
				var hashParser = current_hash.replace(/^#/, '');
				hashParser = hashParser.split('&');
				var action = hashParser[0];
				var callback = eval(hashParser[1]);
				var params = hashParser[2];
				if (action == "")
					window.location.reload(true);
				jQuery.historyCallback(action, callback, params);
			}
		} else {
			// otherwise, check for location.hash
			var current_hash = location.hash.replace(/\?.*$/, '');
			if(current_hash != jQuery.historyCurrentHash) {
				jQuery.historyCurrentHash = current_hash;
				var hashParser = current_hash.replace(/^#/, '');
				hashParser = hashParser.split('&');
				var action = hashParser[0];
				var callback = eval(hashParser[1]);
				var params = hashParser[2];
				if (action == "")
					window.location.reload(true);
				jQuery.historyCallback(action, callback, params);
			}
		}
	},
	historyLoad: function(action, callback, params){
		//hash = decodeURIComponent(hash.replace(/\?.*$/, ''));
		var hash = "#" + action + "&" + getFunctionName(callback, action);
		if (params != undefined)
			hash += "&" + params;
			
		location.hash = hash;
		jQuery.historyCurrentHash = hash;
		
		
		if (jQuery.historyNeedIframe && (jQuery.browser.msie && (jQuery.browser.version < 8))) {
			var ihistory = jQuery("#jQuery_history")[0];
			var iframe = ihistory.contentWindow.document;
			iframe.open();
			iframe.close();
			iframe.location.hash = hash;
			jQuery.lastHistoryLength = history.length;
			jQuery.historyCallback(action, callback, params);
		}
		else if (jQuery.browser.safari) {
			jQuery.dontCheck = true;
			// Manually keep track of the history values for Safari
			this.historyAddHistory(hash);
			
			// Wait a while before allowing checking so that Safari has time to update the "history" object
			// correctly (otherwise the check loop would detect a false change in hash).
			var fn = function() {jQuery.dontCheck = false;};
			window.setTimeout(fn, 200);
			jQuery.historyCallback(action, callback, params);
			// N.B. "location.hash=" must be the last line of code for Safari as execution stops afterwards.
			//      By explicitly using the "location.hash" command (instead of using a variable set to "location.hash") the
			//      URL in the browser and the "history" object are both updated correctly.
			location.hash = hash;
		}
		else {
			jQuery.historyCallback(action, callback, params);
		}
	}
});