// http://www.frank-rahn.de/examples/ajax/

var request;
var destination;
var instances=0;
var objs=[];


function processStateChange()
{
	switch (request.readyState)
	{
		case 0: 	// uninitialized
		case 1: 	// loading
		case 2: 	// loaded
					contentDiv = document.getElementById(destination);
					if (contentDiv)
					{
						contentDiv.style.cursor = "wait";
					}
					break;
		case 3: 	// interactive
					break;
		case 4: 	// complete
					contentDiv = document.getElementById(destination);
					if (contentDiv)
					{
						if (request.status == 200 || request.status == 0)
						{
							response = request.responseText;
							contentDiv.innerHTML = response;
						}
						else
						{
							contentDiv.innerHTML = "<p style=\"color: red;\">Error: Status " + request.status + ", Message: " + request.statusText + "</p>";
						}
						contentDiv.style.cursor = "auto";
					}
					else
					{
						window.status = "No Content-DIV found";
					}
					break;
		default:	contentDiv = document.getElementById(destination);
					if (contentDiv)
					{
						contentDiv.innerHTML = "<p style=\"color: red;\">Error: Unknown Ready State</p>";
					}
					else
					{
						window.status = "No Content-DIV found and unknown Ready State";
					}
					contentDiv.style.cursor = "auto";
					break;
	}
}


function loadHTML(url, dest, data)
{
	destination = dest;
	if (window.XMLHttpRequest)
	{
		// Non-IE browsers, exc. IE7!
		request = new XMLHttpRequest();
	}
	else if (window.ActiveXObject)
	{
		// IE browser
		try
		{
			request = new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch(e)
		{
			request = new ActiveXObject("Microsoft.XMLHTTP");
		}
	}
	else
	{
		request = new XMLHttpRequestOld();
	}

	request.onreadystatechange = processStateChange;
	request.open("POST", url, true);

	if (data)
	{
		request.setRequestHeader("Content-Type", "text/xml");
	}
	request.send(data);
}


function XMLHttpRequestOld()
{
	var i = 0;
	var url = '';
	var responseText = '';
	var responseXML = null;

	this.onreadystatechange = function()
	{
		return false;
	}

	this.open = function(method, url, b)
	{
		// TODO: POST methods
		this.i = ++instances; // id number of this request
		this.url = url;
		var iframe = document.createElement("<iframe id=\"Rahn_iframe_" + this.i + "\" style=\"display:none\" type=\"text/plain\"></iframe>");
		document.body.appendChild(iframe);
	}

	this.send = function(postdata)
	{
		// TODO: use the postdata
		var el = document.getElementById('Rahn_iframe_' + this.i);
		el.src = this.url;
		objs[this.i] = this;
		setTimeout('XMLHttpRequestOld_checkState(' + this.i + ')', 500);
	}

	return true;
}


function XMLHttpRequestOld_checkState(inst)
{
	var el = document.getElementById('Rahn_iframe_' + inst);
	if (el.readyState == 'complete')
	{
		var responseXML = window.frames['Rahn_iframe_' + inst].document.body.childNodes[0];
		objs[inst].responseXML = responseXML;
		objs[inst].responseText = responseXML.data;
		objs[inst].readyState = 4;
		objs[inst].status = 200;
		objs[inst].onreadystatechange();
		el.parentNode.removeChild(el);
	}
	else
	{
		setTimeout('XMLHttpRequestOld_checkState(' + inst + ')', 500);
	}
}