var persisteduls=new Object();
var ddtreemenu=new Object();

ddtreemenu.closefolder="../images/closed.gif"; //set image path to "closed" folder image
ddtreemenu.openfolder="../images/open.gif"; //set image path to "open" folder image

//////////No need to edit beyond here///////////////////////////

ddtreemenu.createTree=function(treeid){
	var ultags=document.getElementById(treeid).getElementsByTagName("ul");
	for (var i=0; i<ultags.length; i++) {
		ddtreemenu.buildSubTree(treeid, ultags[i], i);
	}
}

ddtreemenu.buildSubTree=function(treeid, ulelement, index){
	ulelement.parentNode.className="submenu";
	if (ulelement.getAttribute("rel")==null || ulelement.getAttribute("rel")==false) {//if no cookie and UL has NO rel attribute explicted added by user
		ulelement.setAttribute("rel", "closed");
	} else if (ulelement.getAttribute("rel")=="open") {//else if no cookie and this UL has an explicit rel value of "open"
		ddtreemenu.expandSubTree(treeid, ulelement); //expand this UL plus all parent ULs (so the most inner UL is revealed!)
	}
	ulelement.parentNode.onclick=function(e){
		var submenu=this.getElementsByTagName("ul")[0];
		if (submenu.getAttribute("rel")=="closed"){
			submenu.style.display="block";
			submenu.setAttribute("rel", "open");
			ulelement.parentNode.style.backgroundImage="url("+ddtreemenu.openfolder+")";
		} else if (submenu.getAttribute("rel")=="open"){
			submenu.style.display="none";
			submenu.setAttribute("rel", "closed");
			ulelement.parentNode.style.backgroundImage="url("+ddtreemenu.closefolder+")";
		}
		ddtreemenu.preventpropagate(e);
	}
	ulelement.onclick=function(e){
		ddtreemenu.preventpropagate(e);
	}
}

ddtreemenu.expandSubTree=function(treeid, ulelement){ //expand a UL element and any of its parent ULs
	var rootnode=document.getElementById(treeid);
	var currentnode=ulelement;
	currentnode.style.display="block";
	currentnode.parentNode.style.backgroundImage="url("+ddtreemenu.openfolder+")";
	while (currentnode!=rootnode){
		if (currentnode.tagName=="UL"){ //if parent node is a UL, expand it too
			currentnode.style.display="block";
			currentnode.setAttribute("rel", "open"); //indicate it's open
			currentnode.parentNode.style.backgroundImage="url("+ddtreemenu.openfolder+")";
		}
		currentnode=currentnode.parentNode;
	}
}

ddtreemenu.flatten=function(treeid, action){ //expand or contract all UL elements
	var ultags=document.getElementById(treeid).getElementsByTagName("ul");
	for (var i=0; i<ultags.length; i++){
		ultags[i].style.display=(action=="expand")? "block" : "none";
		var relvalue=(action=="expand")? "open" : "closed";
		ultags[i].setAttribute("rel", relvalue);
		ultags[i].parentNode.style.backgroundImage=(action=="expand")? "url("+ddtreemenu.openfolder+")" : "url("+ddtreemenu.closefolder+")";
	}
}

////A few utility functions below//////////////////////

ddtreemenu.searcharray=function(thearray, value){ //searches an array for the entered value. If found, delete value from array
	var isfound=false;
	for (var i=0; i<thearray.length; i++){
		if (thearray[i]==value){
			isfound=true;
			thearray.shift(); //delete this element from array for efficiency sake
			break;
		}
	}
	return isfound;
}

ddtreemenu.preventpropagate=function(e){ //prevent action from bubbling upwards
	if (typeof e!="undefined") {
		e.stopPropagation();
	} else {
		event.cancelBubble=true;
	}
}

ddtreemenu.dotask=function(target, functionref, tasktype){ //assign a function to execute to an event handler (ie: onunload)
	var tasktype=(window.addEventListener)? tasktype : "on"+tasktype;
	if (target.addEventListener) {
		target.addEventListener(tasktype, functionref, false);
	} else if (target.attachEvent) {
		target.attachEvent(tasktype, functionref);
	}
}