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

ddtreemenu.closefolder="/vocabweb/img/bullet-arrow-right.gif" //set image path to "closed" folder image
ddtreemenu.openfolder="/vocabweb/img/bullet-arrow-down.gif" //set image path to "open" folder image

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

ddtreemenu.createTree=function(treeid, enablepersist, persistdays) {
  var ultags=getObj(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+")"
      ulelement.parentNode.style.backgroundRepeat="no-repeat";
    }
    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!)
  
  var onclickfunction = 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+")"
      ulelement.parentNode.style.backgroundRepeat="no-repeat";
    }
    else if (submenu.getAttribute("rel")=="open"){
      submenu.style.display="none"
      submenu.setAttribute("rel", "closed")
      ulelement.parentNode.style.backgroundImage="url("+ddtreemenu.closefolder+")"
      ulelement.parentNode.style.backgroundRepeat="no-repeat";
    }
    ddtreemenu.preventpropagate(e)
  }
  if ( navigator.userAgent.indexOf("Safari/3") != -1 ||  navigator.userAgent.indexOf("Safari/4") != -1) {
    ulelement.parentNode.addEventListener('click',onclickfunction,false);
  }
  else {
    ulelement.parentNode.onclick=onclickfunction;
  }


  if ( navigator.userAgent.indexOf("Safari/3") != -1 || navigator.userAgent.indexOf("Safari/4") != -1) {
    ulelement.addEventListener('click',function(e){ddtreemenu.preventpropagate(e)},false);
  }
  else {
    ulelement.onclick=function(e){  ddtreemenu.preventpropagate(e)  }
  }
}

ddtreemenu.expandSubTree=function(treeid, ulelement){ //expand a UL element and any of its parent ULs
  var rootnode=getObj(treeid);
  var currentnode=ulelement
  currentnode.style.display="block"
  currentnode.parentNode.style.backgroundImage="url("+ddtreemenu.openfolder+")"
  currentnode.parentNode.style.backgroundRepeat="no-repeat";
  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.parentNode.style.backgroundRepeat="no-repeat";
    }
    currentnode=currentnode.parentNode
  }
}

ddtreemenu.flatten=function(treeid, action){ //expand or contract all UL elements
  var ultags=getObj(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+")"
    ultags[i].parentNode.style.backgroundRepeat="no-repeat";
  }
}

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