//Chrome Drop Down Menu v2.01- Author: Dynamic Drive (http://www.dynamicdrive.com)
//Last updated: November 14th 06- added iframe shim technique
// Modifications to add support to look at other tags for rel="" support by Andrew Chung, 2008-06-04

var cssdropdown={
  // Default values unless overridden
  disappeardelay: 250,    //set delay in miliseconds before menu disappears onmouseout
  disablemenuclick: true, //when user clicks on a menu item with a drop down menu, disable menu item's link?
  enableswipe: 1,         //enable swipe effect? 1 for yes, 0 for no
  enableiframeshim: 1,    //enable "iframe shim" technique to get drop down menus to correctly appear on top of controls such as form objects in IE5.5/IE6? 1 for yes, 0 for no
  menutag: "a",           //tag to look for menu items with rel="" attributes
  menuattr: "rel",        //Attribute name in the tag used to reference the drop down menu

  //No need to edit beyond here////////////////////////
  dropmenuobj: null, ie: document.all, firefox: document.getElementById&&!document.all, swipetimer: undefined, bottomclip:0,

  getposOffset:function(what, offsettype){
    var totaloffset=(offsettype=="left")? what.offsetLeft : what.offsetTop;
    var parentEl=what.offsetParent;
    while (parentEl!=null){
      totaloffset=(offsettype=="left")? totaloffset+parentEl.offsetLeft : totaloffset+parentEl.offsetTop;
      parentEl=parentEl.offsetParent;
    }
    return totaloffset;
  },

  swipeeffect:function(){
    if (this.bottomclip<parseInt(this.dropmenuobj.offsetHeight)){
      this.bottomclip+=10+(this.bottomclip/10) //unclip drop down menu visibility gradually
      this.dropmenuobj.style.clip="rect(0 auto "+this.bottomclip+"px 0)"
    }
    else
      return
    this.swipetimer=setTimeout("cssdropdown.swipeeffect()", 10)
  },

  showhide:function(obj, e){
    if (this.ie || this.firefox)
      this.dropmenuobj.style.left=this.dropmenuobj.style.top="-500px";
    if (e.type=="click" && obj.visibility==hidden || e.type=="mouseover"){
      if (this.enableswipe==1){
        if (typeof this.swipetimer!="undefined")
          clearTimeout(this.swipetimer);
        obj.clip="rect(0 auto 0 0)"; //hide menu via clipping
        this.bottomclip=0;
        this.swipeeffect();
      }
      obj.visibility="visible";
    }
    else if (e.type=="click")
      obj.visibility="hidden";
  },

  iecompattest:function(){
    return (document.compatMode && document.compatMode!="BackCompat")? document.documentElement : document.body;
  },

  clearbrowseredge:function(obj, whichedge){
    var edgeoffset=0
    if (whichedge=="rightedge"){
      var windowedge=this.ie && !window.opera? this.iecompattest().scrollLeft+this.iecompattest().clientWidth-15 : window.pageXOffset+window.innerWidth-15
      this.dropmenuobj.contentmeasure=this.dropmenuobj.offsetWidth
      if (windowedge-this.dropmenuobj.x < this.dropmenuobj.contentmeasure)  //move menu to the left?
        edgeoffset=this.dropmenuobj.contentmeasure-obj.offsetWidth
    }
    else{
      var topedge=this.ie && !window.opera? this.iecompattest().scrollTop : window.pageYOffset
      var windowedge=this.ie && !window.opera? this.iecompattest().scrollTop+this.iecompattest().clientHeight-15 : window.pageYOffset+window.innerHeight-18
      this.dropmenuobj.contentmeasure=this.dropmenuobj.offsetHeight
      if (windowedge-this.dropmenuobj.y < this.dropmenuobj.contentmeasure){ //move up?
        edgeoffset=this.dropmenuobj.contentmeasure+obj.offsetHeight
        if ((this.dropmenuobj.y-topedge)<this.dropmenuobj.contentmeasure) //up no good either?
          edgeoffset=this.dropmenuobj.y+obj.offsetHeight-topedge
      }
    }
    return edgeoffset
  },

  dropit:function(obj, e, dropmenuID){
    if (this.dropmenuobj!=null) //hide previous menu
      this.dropmenuobj.style.visibility="hidden" //hide menu
    this.clearhidemenu()
    if (this.ie||this.firefox){
      obj.onmouseout=function(){cssdropdown.delayhidemenu()}
      obj.onclick=function(){return !cssdropdown.disablemenuclick} //disable main menu item link onclick?
      this.dropmenuobj=document.getElementById(dropmenuID)
      this.dropmenuobj.onmouseover=function(){cssdropdown.clearhidemenu()}
      this.dropmenuobj.onmouseout=function(e){cssdropdown.dynamichide(e)}
      this.dropmenuobj.onclick=function(){cssdropdown.delayhidemenu()}
      this.showhide(this.dropmenuobj.style, e)
      this.dropmenuobj.x=this.getposOffset(obj, "left")
      this.dropmenuobj.y=this.getposOffset(obj, "top")
      this.dropmenuobj.style.left=this.dropmenuobj.x-this.clearbrowseredge(obj, "rightedge")+"px"
      this.dropmenuobj.style.top=this.dropmenuobj.y-this.clearbrowseredge(obj, "bottomedge")+obj.offsetHeight+1+"px"
      this.positionshim() //call iframe shim function
    }
  },

  positionshim:function(){ //display iframe shim function
  if (this.enableiframeshim && typeof this.shimobject!="undefined"){
    if (this.dropmenuobj.style.visibility=="visible"){
      this.shimobject.style.width=this.dropmenuobj.offsetWidth+"px"
      this.shimobject.style.height=this.dropmenuobj.offsetHeight+"px"
      this.shimobject.style.left=this.dropmenuobj.style.left
      this.shimobject.style.top=this.dropmenuobj.style.top
    }
    this.shimobject.style.display=(this.dropmenuobj.style.visibility=="visible")? "block" : "none"
    }
  },

  hideshim:function(){
    if (this.enableiframeshim && typeof this.shimobject!="undefined")
      this.shimobject.style.display='none'
  },

  contains_firefox:function(a, b) {
    while (b && b.parentNode)
      if ((b = b.parentNode) == a)
        return true;
    return false;
  },

  dynamichide:function(e){
    var evtobj=window.event? window.event : e
    if (this.ie&&!this.dropmenuobj.contains(evtobj.toElement))
      this.delayhidemenu()
    else if (this.firefox&&e.currentTarget!= evtobj.relatedTarget&& !this.contains_firefox(evtobj.currentTarget, evtobj.relatedTarget))
      this.delayhidemenu()
  },

  delayhidemenu:function(){
    this.delayhide=setTimeout("cssdropdown.dropmenuobj.style.visibility='hidden'; cssdropdown.hideshim()",this.disappeardelay) //hide menu
  },

  clearhidemenu:function(){
    if (this.delayhide!="undefined")
      clearTimeout(this.delayhide)
  },

  startchrome:function(){
    var tag = this.menutag;
    var lnk = this.menuattr;
    for (var ids=0; ids<arguments.length; ids++){
      var menuitems=document.getElementById(arguments[ids]).getElementsByTagName(tag)
      for (var i=0; i<menuitems.length; i++){
        if (menuitems[i].getAttribute(lnk)){
          var relvalue=menuitems[i].getAttribute(lnk)
          menuitems[i].onmouseover=function(e){
            var event=typeof e!="undefined"? e : window.event
            cssdropdown.dropit(this,event,this.getAttribute(lnk))
          }
        }
      }
    }
    if (window.createPopup && !window.XmlHttpRequest){ //if IE5.5 to IE6, create iframe for iframe shim technique
      document.write('<IFRAME id="iframeshim"  src="" style="display: none; left: 0; top: 0; z-index: 90; position: absolute; filter: progid:DXImageTransform.Microsoft.Alpha(style=0,opacity=0)" frameBorder="0" scrolling="no"></IFRAME>')
      this.shimobject=document.getElementById("iframeshim") //reference iframe object
    }
  }

}