//
// Copyright (c) 2005, Michael Schwarz. (http://www.schwarz-interactive.de/)
// All rights reserved.
//   

var requests = [];

if(typeof(XMLHttpRequest) == 'undefined')
var XMLHttpRequest=function()
{
	var request = null;
	try
	{
		request = new ActiveXObject('Msxml2.XMLHTTP');
	}
	catch(e)
	{
		try
		{
			request = new ActiveXObject('Microsoft.XMLHTTP');
		}
		catch(ee)
		{}
	}
	return request;
}

function ajax_create_request()
{
	for(var i=0; i<requests.length; i++)
	{
		if(requests[i].readyState == 4)
		{
			requests[i].abort();
			return requests[i];
		}
	}
	
	requests[requests.length] = new XMLHttpRequest();
	return requests[requests.length -1];
}

function ajax_request(url, data, callback)
{
	var request = ajax_create_request();
	var async = typeof(callback) == 'function';
	
	if(request)
	{
		if(async) request.onreadystatechange = function()
		{
			if(request.readyState == 4)
				callback(new ajax_response(request));
		}
	}
	
	request.open('POST', url + '&' + data, async);
	request.send('');
	
	if(!async)
		return new ajax_response(request);
}

function ajax_response(request)
{
	this.request = request;
	this.error = null;
	this.value = null;
	
	if(request.status == 200)
	{
		try
		{
			this.value = object_from_json(request.responseText);
		}
		catch(e)
		{
			this.error = e;
		}
	}
	else
	{
		this.error = 'HTTP ' + request.status;
	}
	
	return this;
}

function enc(s)
{
	return escape(escape(s).replace(/\+/g,'%2C').replace(/\"/g,'%22').replace(/\'/g,'%27'));
}

function json_from_object(o)
{

}

function object_from_json(text)
{
	var r = null;
	eval('r='+text+';');
	return r;
}