//Drop Down/ Overlapping Content: http://www.dynamicdrive.com
//**Updated: Dec 19th, 07': Added ability to dynamically populate a Drop Down content using an external file (Ajax feature)
//**Updated: Feb 29th, 08':
		//1) Added ability to reveal drop down content via "click" of anchor link (instead of default "mouseover")
		//2) Added ability to disable drop down content from auto hiding when mouse rolls out of it
		//3) Added hidediv(id) public function to directly hide drop down div dynamically

var dropdowncontent={
    disableanchorlink: true, //when user clicks on anchor link, should link itself be disabled (always true if "revealbehavior" above set to "click")
 hidedivmouseout: [true, 200], //Set hiding behavior within Drop Down DIV itself: [hide_div_onmouseover?, miliseconds_before_hiding]
    ajaxloadingmsg: "Loading content. Please wait...", //HTML to show while ajax page is being feched, if applicable
    ajaxbustcache: true, //Bust cache when fetching Ajax pages?

    getposOffset:function(what, offsettype){
	return (what.offsetParent)? what[offsettype]+this.getposOffset(what.offsetParent, offsettype) : what[offsettype]
    },

    isContained:function(m, e){
	var e=window.event || e
	var c=e.relatedTarget || ((e.type=="mouseover")? e.fromElement : e.toElement)
	while (c && c!=m)try {c=c.parentNode} catch(e){c=m}
	if (c==m)
	    return true
	else
	    return false
    },

    show:function(anchorobj, subobj, e){
	if (!this.isContained(anchorobj, e)){
	    var e=window.event || e
	    if (e.type=="click" && subobj.style.visibility=="visible"){
		subobj.style.visibility="hidden"
		return
	    }
	    var horizontaloffset=(subobj.dropposition[0]=="left")? -(subobj.offsetWidth-anchorobj.offsetWidth) : 0 //calculate user added horizontal offset
	    var verticaloffset=(subobj.dropposition[1]=="top")? -subobj.offsetHeight : anchorobj.offsetHeight //calculate user added vertical offset
	    subobj.style.left=this.getposOffset(anchorobj, "offsetLeft") + horizontaloffset + "px"
	    subobj.style.top=this.getposOffset(anchorobj, "offsetTop")+verticaloffset+"px"
	    subobj.style.clip=(subobj.dropposition[1]=="top")? "rect(auto auto auto 0)" : "rect(0 auto 0 0)" //hide drop down box initially via clipping
	    subobj.style.visibility="visible"
	    subobj.startTime=new Date().getTime()
	    subobj.contentheight=parseInt(subobj.offsetHeight)
	    if (typeof window["hidetimer_"+subobj.id]!="undefined") //clear timer that hides drop down box?
		clearTimeout(window["hidetimer_"+subobj.id])
	    this.slideengine(subobj, (subobj.dropposition[1]=="top")? "up" : "down")
	}
    },

    curveincrement:function(percent){
	return (1-Math.cos(percent*Math.PI)) / 2 //return cos curve based value from a percentage input
    },

    slideengine:function(obj, direction){
	var elapsed=new Date().getTime()-obj.startTime //get time animation has run
	if (elapsed<obj.glidetime){ //if time run is less than specified length
	    var distancepercent=(direction=="down")? this.curveincrement(elapsed/obj.glidetime) : 1-this.curveincrement(elapsed/obj.glidetime)
	    var currentclip=(distancepercent*obj.contentheight)+"px"
	    obj.style.clip=(direction=="down")? "rect(0 auto "+currentclip+" 0)" : "rect("+currentclip+" auto auto 0)"
	    window["glidetimer_"+obj.id]=setTimeout(function(){dropdowncontent.slideengine(obj, direction)}, 10)
	}
	else{ //if animation finished
	    obj.style.clip="rect(0 auto auto 0)"
	}
    },

    hide:function(activeobj, subobj, e){
	if (!dropdowncontent.isContained(activeobj, e)){
	    window["hidetimer_"+subobj.id]=setTimeout(function(){
		subobj.style.visibility="hidden"
		subobj.style.left=subobj.style.top=0
		clearTimeout(window["glidetimer_"+subobj.id])
	    }, dropdowncontent.hidedivmouseout[1])
	}
    },

    hidediv:function(subobjid){
	document.getElementById(subobjid).style.visibility="hidden"
    },

    ajaxconnect:function(pageurl, divId){
	var page_request = false
	var bustcacheparameter=""
	if (window.XMLHttpRequest) // if Mozilla, IE7, Safari etc
	    page_request = new XMLHttpRequest()
	else if (window.ActiveXObject){ // if IE6 or below
	    try {
	    page_request = new ActiveXObject("Msxml2.XMLHTTP")
	    } 
	    catch (e){
		try{
		page_request = new ActiveXObject("Microsoft.XMLHTTP")
		}
		catch (e){}
	    }
	}
	else
	    return false
	document.getElementById(divId).innerHTML=this.ajaxloadingmsg //Display "fetching page message"
	page_request.onreadystatechange=function(){dropdowncontent.loadpage(page_request, divId)}
	if (this.ajaxbustcache) //if bust caching of external page
	    bustcacheparameter=(pageurl.indexOf("?")!=-1)? "&"+new Date().getTime() : "?"+new Date().getTime()
	page_request.open('GET', pageurl+bustcacheparameter, true)
	page_request.send(null)
    },

    loadpage:function(page_request, divId){
	if (page_request.readyState == 4 && (page_request.status==200 || window.location.href.indexOf("http")==-1)){
	    document.getElementById(divId).innerHTML=page_request.responseText
	}
    },

 init:function(anchorid, pos, glidetime, revealbehavior){
	var anchorobj=document.getElementById(anchorid)
	var subobj=document.getElementById(anchorobj.getAttribute("rel"))
	var subobjsource=anchorobj.getAttribute("rev")
	if (subobjsource!=null && subobjsource!="")
	    this.ajaxconnect(subobjsource, anchorobj.getAttribute("rel"))
	subobj.dropposition=pos.split("-")
	subobj.glidetime=glidetime || 1000
	subobj.style.left=subobj.style.top=0
	if (typeof revealbehavior=="undefined" || revealbehavior=="mouseover"){
	    anchorobj.onmouseover=function(e){dropdowncontent.show(this, subobj, e)}
	    anchorobj.onmouseout=function(e){dropdowncontent.hide(subobj, subobj, e)}
	    if (this.disableanchorlink) anchorobj.onclick=function(){return false}
	}
	else
	    anchorobj.onclick=function(e){dropdowncontent.show(this, subobj, e); return false}
	if (this.hidedivmouseout[0]==true) //hide drop down DIV when mouse rolls out of it?
	    subobj.onmouseout=function(e){dropdowncontent.hide(this, subobj, e)}
    }
}