/*
 ======================================================================
 RSS JavaScript Ticker object
 Author: George at JavaScriptKit.com/ DynamicDrive.com
 Created: Feb 5th, 2006. Updated: Feb 5th, 2006
 ======================================================================
*/

function createAjaxObj(){
var httprequest=false
if (window.XMLHttpRequest){ // if Mozilla, Safari etc
httprequest=new XMLHttpRequest()
if (httprequest.overrideMimeType)
httprequest.overrideMimeType('text/xml')
}
else if (window.ActiveXObject){ // if IE
try {
httprequest=new ActiveXObject("Msxml2.XMLHTTP");
} 
catch (e){
try{
httprequest=new ActiveXObject("Microsoft.XMLHTTP");
}
catch (e){}
}
}
return httprequest
}

// -------------------------------------------------------------------
// Main RSS Ticker Object function
// rss_ticker(RSS_id, cachetime, divId, divClass, delay, optionalswitch)
// -------------------------------------------------------------------

function rss_ticker(RSS_id, cachetime, divId, divClass, delay, optionalswitch){
this.RSS_id=RSS_id //Array key indicating which RSS feed to display
this.cachetime=cachetime //Time to cache feed, in minutes. 0=no cache.
this.tickerid=divId //ID of ticker div to display information
this.delay=delay //Delay between msg change, in miliseconds.
this.logicswitch=(typeof optionalswitch!="undefined")? optionalswitch : -1
this.mouseoverBol=0 //Boolean to indicate whether mouse is currently over ticker (and pause it if it is)
this.pointer=0
this.ajaxobj=createAjaxObj()
document.write('<div align="center" id="'+divId+'" class="'+divClass+'">Initializing ticker...</div>')
this.getAjaxcontent()
}

// -------------------------------------------------------------------
// getAjaxcontent()- Makes asynchronous GET request to "rssfetch.php" with the supplied parameters
// -------------------------------------------------------------------

rss_ticker.prototype.getAjaxcontent=function(){
if (this.ajaxobj){
var instanceOfTicker=this
var parameters="id="+encodeURIComponent(this.RSS_id)+"&cachetime="+this.cachetime+"&bustcache="+new Date().getTime()
this.ajaxobj.onreadystatechange=function(){instanceOfTicker.initialize()}
this.ajaxobj.open('GET', "rssfetch.php?"+parameters, true)
this.ajaxobj.send(null)
}
}

// -------------------------------------------------------------------
// initialize()- Initialize ticker method.
// -Gets contents of RSS content and parse it using JavaScript DOM methods 
// -------------------------------------------------------------------

rss_ticker.prototype.initialize=function(){ 
if (this.ajaxobj.readyState == 4){ //if request of file completed
if (this.ajaxobj.status==200){ //if request was successful
var xmldata=this.ajaxobj.responseXML
if(xmldata.getElementsByTagName("item").length==0){ //if no <item> elements found in returned content
document.getElementById(this.tickerid).innerHTML="<b>Error</b> fetching remote RSS feed!<br />"+this.ajaxobj.responseText
return
}
var instanceOfTicker=this
this.feeditems=xmldata.getElementsByTagName("item")

//Cycle through RSS XML object and store each peice of the item element as an attribute of the element
for (var i=0; i<this.feeditems.length; i++){
this.feeditems[i].setAttribute("ctitle", this.feeditems[i].getElementsByTagName("title")[0].firstChild.nodeValue)
this.feeditems[i].setAttribute("clink", this.feeditems[i].getElementsByTagName("link")[0].firstChild.nodeValue)
this.feeditems[i].setAttribute("cdescription", this.feeditems[i].getElementsByTagName("description")[0].firstChild.nodeValue)
}
document.getElementById(this.tickerid).onmouseover=function(){instanceOfTicker.mouseoverBol=1}
document.getElementById(this.tickerid).onmouseout=function(){instanceOfTicker.mouseoverBol=0}
this.rotatemsg()
}
}
}

// -------------------------------------------------------------------
// rotatemsg()- Rotate through RSS messages and displays them
// -------------------------------------------------------------------

rss_ticker.prototype.rotatemsg=function(){
var instanceOfTicker=this
if (this.mouseoverBol==1) //if mouse is currently over ticker, do nothing (pause it)
setTimeout(function(){instanceOfTicker.rotatemsg()}, 100)
else{
var tickerDiv=document.getElementById(this.tickerid)
var tickercontent='<a href="'+this.feeditems[this.pointer].getAttribute("clink")+'">'+this.feeditems[this.pointer].getAttribute("ctitle")+'</a>'
if (this.logicswitch=="showdescription")
tickercontent+="<br /><br />"+this.feeditems[this.pointer].getAttribute("cdescription")
tickerDiv.innerHTML=tickercontent
this.pointer=(this.pointer<this.feeditems.length-1)? this.pointer+1 : 0
setTimeout(function(){instanceOfTicker.rotatemsg()}, this.delay) //update container every second
}
}