tabcontent

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=[] //Array to store position of tabs that have a "rel" attr defined, relative to all tab links, within container
 this.subcontentids=[] //Array to store ids of the sub contents ("rel" attr values)
 this.revcontentids=[] //Array to store ids of arbitrary contents to expand/contact as well ("rev" attr values)
 this.selectedClassTarget="link" //keyword to indicate which target element to assign "selected" CSS class ("linkparent" or "link")
}

ddtabcontent.getCookie=function(Name){
 var re=new RegExp(Name+"=[^;]+", "i"); //construct RE to search for target name/value pair
 if (document.cookie.match(re)) //if cookie found
  return document.cookie.match(re)[0].split("=")[1] //return its value
 return ""
}

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

ddtabcontent.prototype={

 expandit:function(tabid_or_position){ //PUBLIC function to select a tab either by its ID or position(int) within its peers
  this.cancelautorun() //stop auto cycling of tabs (if running)
  var tabref=""
  try{
   if (typeof tabid_or_position=="string" && document.getElementById(tabid_or_position).getAttribute("rel")) //if specified tab contains "rel" attr
    tabref=document.getElementById(tabid_or_position)
   else if (parseInt(tabid_or_position)!=NaN && this.tabs[tabid_or_position].getAttribute("rel")) //if specified tab contains "rel" attr
    tabref=this.tabs[tabid_or_position]
  }
  catch(err){alert("Invalid Tab ID or position entered!")}
  if (tabref!="") //if a valid tab is found based on function parameter
   this.expandtab(tabref) //expand this tab
 },

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

 setselectedClassTarget:function(objstr){ //PUBLIC function to set which target element to assign "selected" CSS class ("linkparent" or "link")
  this.selectedClassTarget=objstr || "link"
 },

 getselectedClassTarget:function(tabref){ //Returns target element to assign "selected" CSS class to
  return (this.selectedClassTarget==("linkparent".toLowerCase()))? tabref.parentNode : tabref
 },

 expandtab:function(tabref){
  var subcontentid=tabref.getAttribute("rel") //Get id of subcontent to expand
  //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) //if persistence enabled, save selected tab position(int) relative to its peers
   ddtabcontent.setCookie(this.tabinterfaceid, tabref.tabposition)
 },

 expandsubcontent:function(subcontentid){
  for (var i=0; i<this.subcontentids.length; i++){
   var subcontent=document.getElementById(this.subcontentids[i]) //cache current subcontent obj (in for loop)
   subcontent.style.display=(subcontent.id==subcontentid)? "block" : "none" //"show" or hide sub content based on matching id attr value
  }
 },

 expandrevcontent:function(associatedrevids){
  var allrevids=this.revcontentids
  for (var i=0; i<allrevids.length; i++){ //Loop through rev attributes for all tabs in this tab interface
   //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"
  }
 },

 autorun:function(){ //function to auto cycle through and select tabs based on a set interval
  var currentTabIndex=this.automode_currentTabIndex //index within this.hottabspositions to begin
  var hottabspositions=this.hottabspositions //Array containing position numbers of "hot" tabs (those with a "rel" attr)
  this.expandtab(this.tabs[hottabspositions[currentTabIndex]])
  this.automode_currentTabIndex=(currentTabIndex<hottabspositions.length-1)? currentTabIndex+1 : 0 //increment currentTabIndex
 },

 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 persisterror=true //Bool variable to check whether persisted tab position is valid (can become invalid if user has modified tab structure)
  this.automodeperiod=automodeperiod || 0
  for (var i=0; i<this.tabs.length; i++){
   this.tabs[i].tabposition=i //remember position of tab relative to its peers
   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() //stop auto cycling of tabs (if running)
     return false
    }
    if (this.tabs[i].getAttribute("rev")){ //if "rev" attr defined, store each value within "rev" as an array element
     this.revcontentids=this.revcontentids.concat(this.tabs[i].getAttribute("rev").split(/\s*,\s*/))
    }
    if (this.enabletabpersistence && parseInt(persistedtab)==i || !this.enabletabpersistence && this.getselectedClassTarget(this.tabs[i]).className=="selected"){
     this.expandtab(this.tabs[i]) //expand current tab if it's the persisted tab, or if persist=off, carries the "selected" CSS class
     persisterror=false //Persisted tab (if applicable) was found, so set "persisterror" to false
     //If currently selected tab's index(i) is greater than 0, this means its not the 1st tab, so set the tab to begin in automode to 1st tab:
     this.automode_currentTabIndex=(i>0)? 0 : 1
    }
   }
  } //END for loop
  if (persisterror) //if an error has occured while trying to retrieve persisted tab (based on its position within its peers)
   this.expandtab(this.tabs[this.hottabspositions[0]]) //Just select first tab that contains a "rel" attr
  if (parseInt(this.automodeperiod)>500 && this.hottabspositions.length>1){
   this.automode_currentTabIndex=this.automode_currentTabIndex || 0
   this.autoruntimer=setInterval(function(){tabinstance.autorun()}, this.automodeperiod)
  }
 } //END int() function