//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)}
	},

// 01/16/09 MT: Added functions for image links and area links within an image map
	
	initLink:function(linkid, pos, glidetime, revealbehavior){
		if (document.getElementById(linkid) != null) {
			var linkobj = document.getElementById(linkid)
			var subid = (linkobj.getAttribute("rel") != null)? linkobj.getAttribute("rel") : linkobj.getAttribute("lang")
			if (document.getElementById(subid) != null) {
				var subobj = document.getElementById(subid)
				var subobjsource = (linkobj.getAttribute("rev") != null)? linkobj.getAttribute("rev") : linkobj.getAttribute("xml:lang")
				if (subobjsource != null && subobjsource != "")
					this.ajaxconnect(subobjsource, subid)
				subobj.dropposition = pos.split("-")
				subobj.glidetime = glidetime || 1000
				subobj.style.left = subobj.style.top = 0
				if (typeof revealbehavior == "undefined" || revealbehavior == "mouseover"){
					linkobj.onmouseover = function(e){dropdowncontent.showLink(this, subobj, e)}
					linkobj.onmouseout = function(e){dropdowncontent.hide(subobj, subobj, e)}
					if (this.disableanchorlink) linkobj.onclick = function(){return false}
				}
				else
					linkobj.onclick = function(e){dropdowncontent.showLink(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)}
			}	
		}
	},

	showLink:function(linkobj, subobj, e){
		if (!this.isContained(linkobj, e) || (e && e.type == "click")){
			var e = window.event || e
			if (e.type == "click" && subobj.style.visibility == "visible"){
				subobj.style.visibility = "hidden"
				return
			}
			if (linkobj.parentNode&&typeof linkobj.parentNode.tagName !== 'undefined' && linkobj.parentNode.tagName.toLowerCase() == 'map'){
				var mapIm = linkobj.parentNode.parentNode.getElementsByTagName('img')
				for (var i_tem = 0; i_tem < mapIm.length; i_tem++)
					if (mapIm[i_tem].getAttribute('usemap', 0) && mapIm[i_tem].getAttribute('usemap', 0).replace(/^.*(#.*)/g,'$1') == '#' + linkobj.parentNode.name) {
						var linkObjOffsetWidth = linkobj.parentNode.parentNode.offsetWidth
						var linkObjOffsetHeight = linkobj.parentNode.parentNode.offsetHeight
					}	
			}
			else if (linkobj.childNodes[0]&&typeof linkobj.childNodes[0].tagName !== 'undefined' && linkobj.childNodes[0].tagName.toLowerCase() == 'img'){
				var linkObjOffsetWidth = linkobj.childNodes[0].offsetWidth
				var linkObjOffsetHeight = linkobj.childNodes[0].offsetHeight
			}
			else {
				var linkObjOffsetWidth = linkobj.offsetWidth
				var linkObjOffsetHeight = linkobj.offsetHeight
			}
			var horizontaloffset = (subobj.dropposition[0] == "left")? -(subobj.offsetWidth - linkObjOffsetWidth) : 0 //calculate user added horizontal offset
			var verticaloffset = (subobj.dropposition[1] == "top")? -subobj.offsetHeight : linkObjOffsetHeight //calculate user added vertical offset
			subobj.style.left = this.getposOffsetLink(linkobj, "offsetLeft") + horizontaloffset + "px"
			subobj.style.top = this.getposOffsetLink(linkobj, "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")
		}
	},
	
	getposOffsetLink:function (what, offsettype){
		if (what.parentNode&&typeof what.parentNode.tagName !== 'undefined' && what.parentNode.tagName.toLowerCase() == 'map'){
			var totaloffset = 0
			var mapIm = what.parentNode.parentNode.getElementsByTagName('img')
			for (var i_tem = 0; i_tem < mapIm.length; i_tem++)
				if (mapIm[i_tem].getAttribute('usemap', 0) && mapIm[i_tem].getAttribute('usemap', 0).replace(/^.*(#.*)/g,'$1') == '#' + what.parentNode.name)
					var parentEl = mapIm[i_tem];
		}
		else if (what.childNodes[0]&&typeof what.childNodes[0].tagName !== 'undefined' && what.childNodes[0].tagName.toLowerCase() == 'img'){
			var totaloffset = (offsettype == "offsetLeft")? what.childNodes[0].offsetLeft : what.childNodes[0].offsetTop;
			var parentEl = what.childNodes[0]
		}
		else {
			var totaloffset = (offsettype == "offsetLeft")? what.offsetLeft : what.offsetTop;
			var parentEl = what.offsetParent;
		}
		while (parentEl != null){
			totaloffset = (offsettype == "offsetLeft")? totaloffset + parentEl.offsetLeft : totaloffset + parentEl.offsetTop;
			parentEl = parentEl.offsetParent;
		}
		return totaloffset;
	}
}