var bustcachevar = 0; //bust potential caching of external pages after initial request? (1=yes, 0=no)
var loadstatustext = "<p id='rec_con'><img src='./images/loading.gif' /> Requesting content...</p>";

////NO NEED TO EDIT BELOW////////////////////////
var loadedobjects = "";
var defaultcontentarray = {};
var bustcacheparameter = "";

function loadpage(page_request, containerid) {
	if (page_request.readyState == 4 && (page_request.status == 200 || window.location.href.indexOf("http") == -1)) {
		document.getElementById(containerid).innerHTML = page_request.responseText;
	}
}

function ajaxpage(url, containerid, targetobj) {
	var page_request = false;
	if (window.XMLHttpRequest) { // if Mozilla, Safari etc
		page_request = new XMLHttpRequest();
	}
	else if (window.ActiveXObject) { // if IE
		try {
			page_request = new ActiveXObject("Msxml2.XMLHTTP");
		} 
		catch (e) {
			try {
				page_request = new ActiveXObject("Microsoft.XMLHTTP");
			}
			catch (e2) {}
		}
	}
	else {
		return false;
	}

	var ullist = targetobj.parentNode.parentNode.getElementsByTagName("li");
	for (var i = 0; i < ullist.length; i++) {
		ullist[i].className = "";  //deselect all tabs
	}
	targetobj.parentNode.className = "selected";  //highlight currently clicked on tab
	if (url.indexOf("#default") != -1) { //if simply show default content within container (verus fetch it via ajax)
		document.getElementById(containerid).innerHTML = defaultcontentarray[containerid];
		return;
	}
	document.getElementById(containerid).innerHTML = loadstatustext;
	page_request.onreadystatechange = function() {
		loadpage(page_request, containerid);
	};
	if (bustcachevar) { //if bust caching of external page
		bustcacheparameter = (url.indexOf("?") != -1) ? "&" + new Date().getTime() : "?" + new Date().getTime();
	}
	page_request.open('GET', url + bustcacheparameter, true);
	page_request.send(null);
}

function loadobjs(revattribute) {
	if (revattribute !== null && revattribute !== "") { //if "rev" attribute is defined (load external .js or .css files)
		var objectlist = revattribute.split(/\s*,\s*/); //split the files and store as array
		for (var i = 0; i < objectlist.length; i++) {
			var file = objectlist[i];
			var fileref = null;
			if (loadedobjects.indexOf(file) == -1) { //Check to see if this object has not already been added to page before proceeding
				if (file.indexOf(".js") != -1) { //If object is a js file
					fileref = document.createElement('script');
					fileref.setAttribute("type","text/javascript");
					fileref.setAttribute("src", file);
				}
				else if (file.indexOf(".css") != -1) { //If object is a css file
					fileref = document.createElement("link");
					fileref.setAttribute("rel", "stylesheet");
					fileref.setAttribute("type", "text/css");
					fileref.setAttribute("href", file);
				}
			}
			if (fileref !== null) {
				document.getElementsByTagName("head").item(0).appendChild(fileref);
				loadedobjects += file + " "; //Remember this object as being already added to page
			}
		}
	}
}

function expandtab(tabcontentid, tabnumber) { //interface for selecting a tab (plus expand corresponding content)
	var thetab = document.getElementById(tabcontentid).getElementsByTagName("a")[tabnumber];
	if (thetab.getAttribute("rel")) {
		ajaxpage(thetab.getAttribute("href"), thetab.getAttribute("rel"), thetab);
		loadobjs(thetab.getAttribute("rev"));
	}
}

function savedefaultcontent(contentid) { // save default ajax tab content
	if (typeof defaultcontentarray[contentid] == "undefined") { //if default content hasn't already been saved
		defaultcontentarray[contentid] = document.getElementById(contentid).innerHTML;
	}
}

function startajaxtabs() {
	for (var i = 0; i < arguments.length; i++) { //loop through passed UL ids
		var ulobj = document.getElementById(arguments[i]);
		var ulist = ulobj.getElementsByTagName("li"); //array containing the LI elements within UL
		for (var x = 0; x < ulist.length; x++) { //loop through each LI element
			var ulistlink = ulist[x].getElementsByTagName("a")[0];
			if (ulistlink.getAttribute("rel")) {
				var modifiedurl = ulistlink.getAttribute("href").replace(/^http:\/\/[^\/]+\//i, "http://"+window.location.hostname+"/");
				ulistlink.setAttribute("href", modifiedurl); //replace URL's root domain with dynamic root domain, for ajax security sake
				savedefaultcontent(ulistlink.getAttribute("rel")); //save default ajax tab content
				ulistlink.onclick = function() {
					ajaxpage(this.getAttribute("href"), this.getAttribute("rel"), this);
					loadobjs(this.getAttribute("rev"));
					return false;
				};
				if (ulist[x].className == "selected") {
					ajaxpage(ulistlink.getAttribute("href"), ulistlink.getAttribute("rel"), ulistlink); //auto load currenly selected tab content
					loadobjs(ulistlink.getAttribute("rev")); //auto load any accompanying .js and .css files
				}
			}
		}
	}
}