/*
 * Folks Ajax Framework
 *
 * Copyright (c) 2008 Eduardo Dias (www.codeplex.com/folks)
 * Licensed under the Ms-PL license.
 *
 */
var Folks = 
{
	//Private fiels
	__evtt : "__EVENTTARGET",
	__evta : "__EVENTARGUMENT",
	__evtv : "__EVENTVALIDATION",
	__vs : "__VIEWSTATE",
	__lf : "__LASTFOCUS",
	
	//Initialization
	init : function()
	{
		$(document).ready(Folks.initialize);
	},
	initialize : function ()
	{
		window.__originalDoPostBack = window.__doPostBack;
		window.__doPostBack = Folks.doPostBack;
		$('form').find(':submit').each(Folks.configureButton);
	},
	//PostBack
	ensureEventTarget : function(eventTarget)
	{
		var target = $('*[name=' + eventTarget + ']');
		
		if(target.length == 0)
			target = $('#' + eventTarget);
		if(target.length == 0)
			target = $('*[name=' + eventTarget.substring(0, eventTarget.lastIndexOf('$')) + ']');
		
		return target;
	},
	ensureEventFields : function()
	{
		var field = '<input type="hidden" />';
		var evtt = $('#' + Folks.__evtt);
		var evta = $('#' + Folks.__evta);
		
		if(evtt.length == 0)
			$(field).attr('id', Folks.__evtt).attr('name', Folks.__evtt).appendTo('form');
			
		if(evta.length == 0)
			$(field).attr('id', Folks.__evta).attr('name', Folks.__evta).appendTo('form');
	},
	doPostBack : function(eventTarget, eventArgument)
	{
		var status = false;
		var target = Folks.ensureEventTarget(eventTarget);
		try
		{
			if(target.is('*[rel=folks]') || target.parents('*[rel=folks]').length > 0)
			{
				Folks.ensureEventFields();
				$('#' + Folks.__evtt).val(eventTarget);
				$('#' + Folks.__evta).val(eventArgument);
				var data = Folks.parseData(target, eventTarget, eventArgument);
				$.ajax
				(
					{
						url : $('form').attr('action'),
						type : "POST",
						dataType : "html", 
						data : data,
						success : Folks.renderResponse, 
						error : Folks.renderError
					}
				);
				status = true;
			}
			else if(window.__originalDoPostBack != null)
			{
				window.__originalDoPostBack(eventTarget, eventArgument);
				status = true;
			}
		}
		catch(ex)
		{
			if(ex != null && ex.message != null)
				alert(ex.message);
		}
		if(target.is(':submit'))
			return status;
	},
	//Parse
	parseData : function(target, eventTarget, eventArgument)
	{
		var data = {};
		var dataStr = "data = {";
		if(!target.is(':radio,:checkbox,:submit'))
			dataStr += Folks.parseCommonForm();
		else
			dataStr += Folks.parseRadioCheckboxSubmit(target, eventArgument);
		dataStr	+= "}";
		eval(dataStr);
		return data;
		
	},
	parseCommonForm : function()
	{
		var dataStr = '';
		var form = Folks.$($('form').attr('id'));
		
		if(form != null && form.elements != null)
			for(var i=0;i<form.elements.length;i++)
				dataStr += Folks.parseDataItem($(form.elements[i]), null, (i<form.elements.length-1)); 
		return dataStr;
	},
	parseRadioCheckboxSubmit : function(target, eventArgument)
	{
		var dataStr = '';
		dataStr += Folks.parseDataItem($('#' + Folks.__evtt), target.attr('name'));
		dataStr += Folks.parseDataItem($('#' + Folks.__evta), eventArgument);
		dataStr += Folks.parseDataItem($('#' + Folks.__evtv));
		dataStr += Folks.parseDataItem($('#' + Folks.__vs));
		dataStr += Folks.parseDataItem($('#' + Folks.__lf));
		dataStr += Folks.parseDataItem(target, target.val());
		var crs = $(':checked');
		crs.each
		(
			function()
			{
				var cr = $(this);
				dataStr += Folks.parseDataItem(cr, cr.val(), (crs.index(cr[0]) < crs.length - 1));
			}
		);
		return dataStr;
	},
	parseDataItem : function(element, value, comma)
	{
		var item = '';
		if(!element.is(':radio,:checkbox') || (element.is(':radio,:checkbox') && element.is(':checked')))
		{
			value = value || element.val();
			if(value != null){
				item += element.attr('name') + ' : ';
				item += '\'' + value + '\'';
				item += (comma == null || comma == true) ? ',' : '';
			}
		}
		return item;	
	},
	//Rendering
	renderResponse : function(response)
	{ 
		$('form').html($('<div>').append(response).find('form').html());
		Folks.initialize();
	},
	renderError : function(request, error, exception)
	{
		if(request.status == '500')
		{
			var response = request.responseText;
			response = response.replace(/[\w\s\S]*<title>/, '');
			response = response.replace(/<\/title>[\w\s\S]*/, '');
			alert(response);
		}
	},
	
	//Utils
	configureButton : function()
	{
		$(this).unbind('click').bind('click', function(){ return !Folks.doPostBack($(this).attr('name'), ''); });
	},
	escape : function(text)
	{
		return text.split('\\').join('\\\\'); 
	},
	$ : function(id)
	{
		return document.getElementById(id);
	}
}
Folks.init();