/***********************************************
* Simple Tree Menu- © Dynamic Drive DHTML code library (www.dynamicdrive.com)
* This notice MUST stay intact for legal use
* Visit Dynamic Drive at http://www.dynamicdrive.com/ for full source code
***********************************************/

var persisteduls = new Object();
var ddtreemenu   = new Object();
	
//////////No need to edit beyond here///////////////////////////

ddtreemenu.createTree = function(treeid, enablepersist, persistdays)
{
	var ultags = document.getElementById(treeid).getElementsByTagName("ul");

	if(typeof persisteduls[treeid] == "undefined")
		persisteduls[treeid] = (enablepersist == true && ddtreemenu.getCookie(treeid) != "") ? ddtreemenu.getCookie(treeid).split(",") : "";

	for(var i = 0 ; i < ultags.length ; i++)
		ddtreemenu.buildSubTree(treeid, ultags[i], i);

	if(enablepersist == true) //if enable persist feature
	{
		var durationdays = (typeof persistdays == "undefined") ? 1 : parseInt(persistdays);

		ddtreemenu.dotask(window, function(){ ddtreemenu.rememberstate(treeid, durationdays); }, "unload"); //save opened UL indexes on body unload
	}
}

ddtreemenu.buildSubTree = function(treeid, ulelement, index)
{
	ulelement.parentNode.className = "submenu";

	if(typeof persisteduls[treeid] == "object") //if cookie exists (persisteduls[treeid] is an array versus "" string)
	{
		if(ddtreemenu.searcharray(persisteduls[treeid], index))
		{
			ulelement.setAttribute("rel", "open");
			ulelement.style.display = "block";
			ulelement.parentNode.style.backgroundImage = "url("+ddtreemenu.openfolder+")";
		}
		else
			ulelement.setAttribute("rel", "closed");
	} //end cookie persist code
	else 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+")";
	}
}

ddtreemenu.rememberstate = function(treeid, durationdays) //store index of opened ULs relative to other ULs in Tree into cookie
{
	var ultags  = document.getElementById(treeid).getElementsByTagName("ul");
	var openuls = new Array();

	for(var i = 0 ; i < ultags.length ; i++)
	{
		if(ultags[i].getAttribute("rel") == "open")
			openuls[openuls.length] = i; //save the index of the opened UL (relative to the entire list of ULs) as an array element
	}

	if(openuls.length == 0) //if there are no opened ULs to save/persist
		openuls[0] = "none open"; //set array value to string to simply indicate all ULs should persist with state being closed

	ddtreemenu.setCookie(treeid, openuls.join(","), durationdays); //populate cookie with value treeid=1,2,3 etc (where 1,2... are the indexes of the opened ULs)
}

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

ddtreemenu.getCookie = function(Name) //get cookie value
{
	var re = new RegExp(Name+"=[^;]+", "i"); //construct RE to search for target name/value pair

	if(document.cookie.match(re)) //if cookie found
		return document.cookie.match(re)[0].split("=")[1]; //return its value

	return "";
}

ddtreemenu.setCookie = function(name, value, days) //set cookei value
{
	var expireDate = new Date();
	//set "expstring" to either future or past date, to set or delete cookie, respectively
	var expstring = expireDate.setDate(expireDate.getDate()+parseInt(days));

	document.cookie = name+"="+value+"; expires="+expireDate.toGMTString()+"; path=/";
}

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);
}