//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



//**Updated: Sept 11th, 08': Fixed bug whereby drop down content isn't revealed onClick of anchor in Safari/ Google Chrome



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) || (e && e.type=="click")){

			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)}

	}

}