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

ddtreemenu.closefolder="../Img/mnuClosed.png" //set image path to "closed" folder image
ddtreemenu.openfolder="../Img/mnuOpen.png" //set image path to "open" folder image

//////////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+")"
}
}

//store index of opened ULs relative to other ULs in Tree into cookie
ddtreemenu.rememberstate=function(treeid, durationdays)
{
   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 ""
}

//set cookei value
ddtreemenu.setCookie=function(name, value, days)
{
   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=/";
}

//searches an array for the entered value. If found, delete value from array
ddtreemenu.searcharray=function(thearray, value)
{
   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
}

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

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