/*
* xajax 0.4
*/

var xajaxDebug=false;
var xajaxRequestURI=false;

function Xajax()
{
	this.DebugMessage = function(text){if (xajaxDebug) alert("Xajax Debug:\n " + text)}
	this.workId = 'xajaxWork'+ new Date().getTime();
	this.depth = 0;

	//Get the XMLHttpRequest Object
	this.getRequestObject = function()
	{
		this.DebugMessage("Initializing Request Object..");				var req;
		try
		{
			req=new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch (e)
		{
			try
			{
				req=new ActiveXObject("Microsoft.XMLHTTP");
			}
			catch (e2)
			{
				req=null;
			}
		}
		if(!req && typeof XMLHttpRequest != "undefined")
		req = new XMLHttpRequest();

		if (!req) this.DebugMessage("Request Object Instantiation failed.");
		return req;
	}

	// xajax.$() is shorthand for document.getElementById() 
	// trap errors if sId is empty or object
	this.$ = function(sId)
	{
		try {
			return document.getElementById(sId);
		} catch(e) {
			return false;
		}
	}

	// xajax.getFormValues() builds a query string XML message from the elements of a form object
	this.getFormValues = function(frm,force)
	{
		var objForm;
		if (!force) force = false; 
		if (typeof(frm) == "string")
			objForm = this.$(frm);
		else
			objForm = frm;
		var sXml = "<xjxquery><q>";
		if (objForm && objForm.tagName == 'FORM')
		{
			var formElements = objForm.elements;
			for( var i=0; i < formElements.length; i++)
			{
				var name = formElements[i].name;
				if (name) {
					if ((formElements[i].type == 'radio' || formElements[i].type == 'checkbox') && formElements[i].checked == false) {
						if (!force) continue;
						var val = formElements[i].checked ? formElements[i].value : '';
					} else {
						var val = formElements[i].value;
					}
					if (sXml != '<xjxquery><q>') {
						sXml += '&';
					}
					sXml += name+"="+encodeURIComponent(val);
				}
			}
		}

		sXml +="</q></xjxquery>";

		return sXml;
	}

	// Generates an XML message that xajax can understand from a javascript object
	this.objectToXML = function(obj)
	{
		var sXml = "<xjxobj>";
		for (i in obj)
		{
			try
			{
				if (i == 'constructor')
				continue;
				if (obj[i] && typeof(obj[i]) == 'function')
				continue;

				var key = i;
				var value = obj[i];
				//if (key == 'cart') alert("typeof:" + typeof(value) + " contr:" + value.constructor);
				if (value && typeof(value)=="object" &&
				(value.constructor == Array
				) && this.depth <= 50)
				{
					//alert("here");
					this.depth++;
					value = this.objectToXML(value);
					this.depth--;
				}

				sXml += "<e><k>"+key+"</k><v>"+value+"</v></e>";

			}
			catch(e)
			{
				this.DebugMessage(e);					}
		}
		sXml += "</xjxobj>";

		return sXml;
	}

	// Sends a XMLHttpRequest to call the specified PHP function on the server
	this.call = function(sFunction, aArgs, sRequestType)
	{
		var i,r,postData;
		//if (document.body)	document.body.style.cursor = 'wait';

		this.DebugMessage("Starting xajax..." + xajaxRequestURI);
		var xajaxRequestType = sRequestType;
		var uri = '/xajax/';

		if ( (location.pathname.substring(0,7) == '/admin/') || (location.pathname.substring(0,6) == 'admin/') ) {
			uri = '/admin/index.php';
		}
		if (xajaxRequestURI != false) {
			uri = xajaxRequestURI;
			
		}

		var value;
		switch(xajaxRequestType)
		{
			case 0:{
				var uriGet = uri.indexOf("?")==-1?"?xajax="+encodeURIComponent(sFunction):"&xajax="+encodeURIComponent(sFunction);
				for (i = 0; i<aArgs.length; i++)
				{
					value = aArgs[i];
					if (typeof(value)=="object")
					value = this.objectToXML(value);
					uriGet += "&xajaxargs[]="+encodeURIComponent(value);
				}
				uriGet += "&xajaxr=" + new Date().getTime();
				uri += uriGet;
				postData = null;
			} break;
			case 1:{
				postData = "xajax="+encodeURIComponent(sFunction);
				postData += "&xajaxr="+new Date().getTime();
				for (i = 0; i <aArgs.length; i++)
				{
					value = aArgs[i];
					if (typeof(value)=="object")
					value = this.objectToXML(value);
					postData = postData+"&xajaxargs[]="+encodeURIComponent(value);
				}
			} break;
			default:
			alert("Illegal request type: " + xajaxRequestType); return false; break;
		}
		r = this.getRequestObject();
		r.open(xajaxRequestType==0?"GET":"POST", uri, true);
		if (xajaxRequestType == 1)
		{
			try
			{
				r.setRequestHeader("Method", "POST " + uri + " HTTP/1.1");
				r.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
			}
			catch(e)
			{
				alert("Your browser does not appear to  support asynchronous requests using POST.");
				return false;
			}
		}
		r.onreadystatechange = function()
		{
			if (r.readyState != 4)
			return;

			if (r.status==200)
			{
				xajax.DebugMessage("Received:\n" + r.responseText);
				var data = r.responseXML;

				if (data)
				xajax.processResponse(data);
			}
		}
		this.DebugMessage("Calling "+sFunction +" uri="+uri+" (post:"+ postData +")");
		r.send(postData);
		this.DebugMessage(sFunction + " waiting..");
		delete r;
		return true;
	}

	// Tests if the new Data is the same as the extant data
	this.willChange = function(element, attribute, newData)
	{
		var oldData;
		if (attribute == "innerHTML")
		{
			tmpXajax = this.$(this.workId);
			if (tmpXajax == null)
			{
				tmpXajax = document.createElement("div");
				tmpXajax.setAttribute('id',this.workId);
				tmpXajax.style.display = "none";
				tmpXajax.style.visibility = "hidden";
				document.body.appendChild(tmpXajax);
			}
			tmpXajax.innerHTML = newData;
			newData = tmpXajax.innerHTML;
		}
		eval("oldData=document.getElementById('"+element+"')."+attribute);
		if (newData != oldData)
		return true;

		return false;
	}

	//Process XML xajaxResponses returned from the request
	this.processResponse = function(xml)
	{
		var tmpXajax = null;

		var oxml = xml;
		xml = xml.documentElement;

		if (!xml) {
			this.DebugMessage("Warning: Empty Response Object..");
			//document.body.style.cursor = 'default';
			return;
		}
		for (var i=0; i<xml.childNodes.length; i++)
		{
			if (xml.childNodes[i].nodeName == "alert")
			{
				if (xml.childNodes[i].firstChild)
				alert(xml.childNodes[i].firstChild.nodeValue);
			}
			if (xml.childNodes[i].nodeName == "jscript")
			{
				if (xml.childNodes[i].firstChild)
				eval(xml.childNodes[i].firstChild.nodeValue);
			}
			if (xml.childNodes[i].nodeName == "update")
			{
				var action;
				var element;
				var attribute;
				var search;
				var data;
				var type;
				var objElement;

				for (j=0; j<xml.childNodes[i].attributes.length; j++)
				{
					if (xml.childNodes[i].attributes[j].name == "action")
					{
						action = xml.childNodes[i].attributes[j].value;
					}
				}

				var node = xml.childNodes[i];
				for (j=0;j<node.childNodes.length;j++)
				{
					if (node.childNodes[j].nodeName == "target")
					{
						for (k=0; k<node.childNodes[j].attributes.length; k++)
						{
							if (node.childNodes[j].attributes[k].name == "attribute")
							{
								attribute = node.childNodes[j].attributes[k].value;
							}
						}
						element = node.childNodes[j].firstChild.nodeValue;
					}
					if (node.childNodes[j].nodeName == "search")
					{
						if (node.childNodes[j].firstChild)
						search = node.childNodes[j].firstChild.nodeValue;
						else
						search = "";
					}
					if (node.childNodes[j].nodeName == "data")
					{
						if (node.childNodes[j].firstChild)
						data = node.childNodes[j].firstChild.nodeValue;
						else
						data = "";
					}

					if (node.childNodes[j].nodeName == "type")
					{
						if (node.childNodes[j].firstChild)
						type = node.childNodes[j].firstChild.nodeValue;
						else
						type = "";
					}
				}
				if (action=="assign")
				{
					if (this.willChange(element,attribute,data))
					{
						eval("document.getElementById('"+element+"')."+attribute+"=data;");
					}
				}
				if (action=="append")
				eval("document.getElementById('"+element+"')."+attribute+"+=data;");
				if (action=="prepend")
				eval("document.getElementById('"+element+"')."+attribute+"=data+document.getElementById('"+element+"')."+attribute);
				if (action=="replace")
				{
					eval("var v=document.getElementById('"+element+"')."+attribute);
					var v2 = v.indexOf(search)==-1?v:"";
					while (v.indexOf(search) > -1)
					{
						x = v.indexOf(search)+search.length+1;
						v2 += v.substr(0,x).replace(search,data);
						v = v.substr(x,v.length-x);
					}
					if (this.willChange(element,attribute,v2))
					eval('document.getElementById("'+element+'").'+attribute+'=v2;');
				}
				if (action=="clear")
				eval("document.getElementById('"+element+"')."+attribute+"='';");
				if (action=="remove")
				{
					objElement = this.$(element);
					if (objElement.parentNode && objElement.parentNode.removeChild)
					{
						objElement.parentNode.removeChild(objElement);
					}
				}
				if (action=="create")
				{
					var objParent = this.$(element);
					objElement = document.createElement(attribute);
					objElement.setAttribute('id',data);
					if (type && type != '')
					objElement.setAttribute('type',type);
					objParent.appendChild(objElement);
					if (objParent.tagName == "FORM")
					{

					}
				}
			}
		}
		//document.body.style.cursor = 'default';
	}
}

var xajax=new Xajax();