function ddtabcontent(tabinterfaceid){
	this.tabinterfaceid=tabinterfaceid //ID of Tab Menu main container
	this.tabs=document.getElementById(tabinterfaceid).getElementsByTagName("a") //Get all tab links within container
	this.enabletabpersistence=true
	this.hottabspositions=[] 
	this.currentTabIndex=0 
	this.subcontentids=[] 
	this.revcontentids=[] 
	this.selectedClassTarget="link"
}

ddtabcontent.getCookie=function(Name){ 
	var re=new RegExp(Name+"=[^;]+", "i"); 
	if (document.cookie.match(re))
		return document.cookie.match(re)[0].split("=")[1]
	return ""
}

ddtabcontent.setCookie=function(name, value){
	document.cookie = name+"="+value+";path=/"
}

ddtabcontent.prototype={

	expandit:function(tabid_or_position){ 
		this.cancelautorun() 
		var tabref=""
		try{
			if (typeof tabid_or_position=="string" && document.getElementById(tabid_or_position).getAttribute("rel"))
				tabref=document.getElementById(tabid_or_position)
			else if (parseInt(tabid_or_position)!=NaN && this.tabs[tabid_or_position].getAttribute("rel")) 
				tabref=this.tabs[tabid_or_position]
		}
		catch(err){alert("Invalid Tab ID or position entered!")}
		if (tabref!="") 
			this.expandtab(tabref)
	},

	cycleit:function(dir, autorun){ 
		if (dir=="next"){
			var currentTabIndex=(this.currentTabIndex<this.hottabspositions.length-1)? this.currentTabIndex+1 : 0
		}
		else if (dir=="prev"){
			var currentTabIndex=(this.currentTabIndex>0)? this.currentTabIndex-1 : this.hottabspositions.length-1
		}
		if (typeof autorun=="undefined") 
			this.cancelautorun() 
		this.expandtab(this.tabs[this.hottabspositions[currentTabIndex]])
	},

	setpersist:function(bool){ //PUBLIC function to toggle persistence feature
			this.enabletabpersistence=bool
	},

	setselectedClassTarget:function(objstr){ 
		this.selectedClassTarget=objstr || "link"
	},

	getselectedClassTarget:function(tabref){ 
		return (this.selectedClassTarget==("linkparent".toLowerCase()))? tabref.parentNode : tabref
	},

	urlparamselect:function(tabinterfaceid){
		var result=window.location.search.match(new RegExp(tabinterfaceid+"=(\\d+)", "i")) //check for "?tabinterfaceid=2" in URL
		return (result==null)? null : parseInt(RegExp.$1) 
	},

	expandtab:function(tabref){
		var subcontentid=tabref.getAttribute("rel") 
		//Get "rev" attr as a string of IDs in the format ",john,george,trey,etc," to easily search through
		var associatedrevids=(tabref.getAttribute("rev"))? ","+tabref.getAttribute("rev").replace(/\s+/, "")+"," : ""
		this.expandsubcontent(subcontentid)
		this.expandrevcontent(associatedrevids)
		for (var i=0; i<this.tabs.length; i++){ //Loop through all tabs, and assign only the selected tab the CSS class "selected"
			this.getselectedClassTarget(this.tabs[i]).className=(this.tabs[i].getAttribute("rel")==subcontentid)? "selected" : ""
		}
		if (this.enabletabpersistence) 
			ddtabcontent.setCookie(this.tabinterfaceid, tabref.tabposition)
		this.setcurrenttabindex(tabref.tabposition) //remember position of selected tab within hottabspositions[] array
	},

	expandsubcontent:function(subcontentid){
		for (var i=0; i<this.subcontentids.length; i++){
			var subcontent=document.getElementById(this.subcontentids[i])
			subcontent.style.display=(subcontent.id==subcontentid)? "block" : "none" 
		}
	},

	expandrevcontent:function(associatedrevids){
		var allrevids=this.revcontentids
		for (var i=0; i<allrevids.length; i++){ 
			//if any values stored within associatedrevids matches one within allrevids, expand that DIV, otherwise, contract it
			document.getElementById(allrevids[i]).style.display=(associatedrevids.indexOf(","+allrevids[i]+",")!=-1)? "block" : "none"
		}
	},

	setcurrenttabindex:function(tabposition){
		for (var i=0; i<this.hottabspositions.length; i++){
			if (tabposition==this.hottabspositions[i]){
				this.currentTabIndex=i
				break
			}
		}
	},

	autorun:function(){ 
		this.cycleit('next', true)
	},

	cancelautorun:function(){
		if (typeof this.autoruntimer!="undefined")
			clearInterval(this.autoruntimer)
	},

	init:function(automodeperiod){
		var persistedtab=ddtabcontent.getCookie(this.tabinterfaceid) //get position of persisted tab (applicable if persistence is enabled)
		var selectedtab=-1 
		var selectedtabfromurl=this.urlparamselect(this.tabinterfaceid) //returns null or index from: tabcontent.htm?tabinterfaceid=index
		this.automodeperiod=automodeperiod || 0
		for (var i=0; i<this.tabs.length; i++){
			this.tabs[i].tabposition=i 
			if (this.tabs[i].getAttribute("rel")){
				var tabinstance=this
				this.hottabspositions[this.hottabspositions.length]=i //store position of "hot" tab ("rel" attr defined) relative to its peers
				this.subcontentids[this.subcontentids.length]=this.tabs[i].getAttribute("rel") //store id of sub content ("rel" attr value)
				this.tabs[i].onclick=function(){
					tabinstance.expandtab(this)
					tabinstance.cancelautorun() 
					return false
				}
				if (this.tabs[i].getAttribute("rev")){ 
					this.revcontentids=this.revcontentids.concat(this.tabs[i].getAttribute("rev").split(/\s*,\s*/))
				}
				if (selectedtabfromurl==i || this.enabletabpersistence && selectedtab==-1 && parseInt(persistedtab)==i || !this.enabletabpersistence && selectedtab==-1 && this.getselectedClassTarget(this.tabs[i]).className=="selected"){
					selectedtab=i //Selected tab index, if found
				}
			}
		} //END for loop
		if (selectedtab!=-1) //if a valid default selected tab index is found
			this.expandtab(this.tabs[selectedtab]) 
		else //if no valid default selected index found
			this.expandtab(this.tabs[this.hottabspositions[0]]) 
		if (parseInt(this.automodeperiod)>500 && this.hottabspositions.length>1){
			this.autoruntimer=setInterval(function(){tabinstance.autorun()}, this.automodeperiod)
		}
	} 

} 