var tIndex = 0;//used when adding elements to the array
var slideshowInterval = 10;
var cb = 0;//currentbanner
var NUM_BANNER_LOCATIONS = 0;
var bannerArray = new Array();
var snippetArray = new Array();

function Banner(theImage, theDescription, theLinkText, theURL, theLinkTarget, theLinkLocation, thePopup, thePopupHeight, thePopupWidth, theBannerLocation){
//the banner object
	this.image = theImage;
	this.description = theDescription;
	this.linktext = theLinkText;
	//theURL == "" ? this.url = "#" : this.url = theURL;
	this.url = theURL;
	theLinkTarget == "Current Window" ? this.linktarget = "_self" : this.linktarget = "_blank";
	this.linklocation = theLinkLocation;
	this.popup = thePopup;
	this.popupHeight = thePopupHeight;
	this.popupWidth = thePopupWidth;
	this.bannerlocation = theBannerLocation;
	this.bannerSnippet = "";
}

function addElement(theImage, theDescription, theLinkText, theURL, theLinkTarget, theLinkLocation, thePopup, thePopupHeight, thePopupWidth, theBannerLocation){
//this function takes bannerArray and makes the current subscript (tIndex) a banner object with the given parameters
	bannerArray[tIndex] = new Banner(theImage, theDescription, theLinkText, theURL, theLinkTarget, theLinkLocation, thePopup, thePopupHeight, thePopupWidth, theBannerLocation);
	//build the bannerSnippet
	if(bannerArray[tIndex].popup =="1")//build the snippet to open in a popup window
	{
		if(bannerArray[tIndex].linklocation == "image")//if the link location is an image...
		{
			if(bannerArray[tIndex].description == "")//if the description is missing
				bannerArray[tIndex].bannerSnippet = '<a href="' + bannerArray[tIndex].url + '" target="Console" onclick="if (window.open) {Console=window.open(this.href,this.target,\'toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars=no,resizable=no,width=' + bannerArray[tIndex].popupWidth + ',height=' + bannerArray[tIndex].popupHeight + '\'); return false;} else { return true;}">' + bannerArray[tIndex].image + '</a>';
			else//assume there is a description
				bannerArray[tIndex].bannerSnippet = '<a href="' + bannerArray[tIndex].url + '" target="Console" onclick="if (window.open) {Console=window.open(this.href,this.target,\'toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars=no,resizable=no,width=' + bannerArray[tIndex].popupWidth + ',height=' + bannerArray[tIndex].popupHeight + '\'); return false;} else { return true;}">' + bannerArray[tIndex].image + '</a><br>' + bannerArray[tIndex].description;
		}
		if(bannerArray[tIndex].linklocation == "description")//if the link location is the description
		{
			if(bannerArray[tIndex].image == "")//if there is no image			
				bannerArray[tIndex].bannerSnippet = bannerArray[tIndex].description + ' <a href="' + bannerArray[tIndex].url + '" target="Console" onclick="if (window.open) {Console=window.open(this.href,this.target,\'toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars=no,resizable=no,width=' + bannerArray[tIndex].popupWidth + ',height=' + bannerArray[tIndex].popupHeight + '\'); return false;} else { return true;}">';
			else//assume there is an image
				bannerArray[tIndex].bannerSnippet = bannerArray[tIndex].image + '<br>' + bannerArray[tIndex].description + ' <a href="' + bannerArray[tIndex].url + '" target="Console" onclick="if (window.open) {Console=window.open(this.href,this.target,\'toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars=no,resizable=no,width=' + bannerArray[tIndex].popupWidth + ',height=' + bannerArray[tIndex].popupHeight + '\'); return false;} else { return true;}">';
				  
			if (bannerArray[tIndex].linktext == "")//if there is no link text
				bannerArray[tIndex].bannerSnippet += 'Click here for more</a>';
			else//assume there is link text
				bannerArray[tIndex].bannerSnippet += bannerArray[tIndex].linktext + '</a>';
		}
	}
	
	else//build snippet to open in a regular window
	{
		var urlLink;
		if(bannerArray[tIndex].linklocation == "image")//if the link location is an image...
		{
			if(bannerArray[tIndex].description == ""){//if the description is missing
				//don't generate a link tag if no url is provided
				bannerArray[tIndex].url == "" ? urlLink = "" : urlLink = '<a href="' + bannerArray[tIndex].url + '" target="' + bannerArray[tIndex].linktarget + '">';
				bannerArray[tIndex].bannerSnippet = urlLink + bannerArray[tIndex].image;
				urlLink != "" ? bannerArray[tIndex].bannerSnippet += '</a>':null;//if there is a link, close the tag
			}
			else{//assume there is a description
				//don't generate a link tag if no url is provided
				bannerArray[tIndex].url == "" ? urlLink = "" : urlLink = '<a href="' + bannerArray[tIndex].url + '" target="' + bannerArray[tIndex].linktarget + '">';
				bannerArray[tIndex].bannerSnippet = urlLink + bannerArray[tIndex].image;
				urlLink != "" ? bannerArray[tIndex].bannerSnippet += '</a>':null;//if there is a link, close the tag
				bannerArray[tIndex].bannerSnippet += '<br>' + bannerArray[tIndex].description;
			}
		}
		if(bannerArray[tIndex].linklocation == "description")//if the link location is the description
		{
			if(bannerArray[tIndex].image == "")//if there is no image
				bannerArray[tIndex].bannerSnippet = bannerArray[tIndex].description + ' <a href="' + bannerArray[tIndex].url + '" target="' + bannerArray[tIndex].linktarget + '">';
			else//assume there is an image
				bannerArray[tIndex].bannerSnippet = bannerArray[tIndex].image + '<br>' + bannerArray[tIndex].description + ' <a href="' + bannerArray[tIndex].url + '" target="' + bannerArray[tIndex].linktarget + '">';	
			if (bannerArray[tIndex].linktext == "")//if there is no link text
				bannerArray[tIndex].bannerSnippet += 'Click here for more</a>';
			else//assume there is link text
				bannerArray[tIndex].bannerSnippet += bannerArray[tIndex].linktext + '</a>';
		}
	}
	//document.write('<form name="form1" method="post" action=""><textarea name="textarea" cols="150" rows="5">' + bannerArray[tIndex].bannerSnippet + '</textarea></form>');
	++tIndex;
}

function build2DArray(){
//the 2-dimensional will contain the banner location, and the banners for that location
//example:  banner[banner_location][banners]
	var eIndex = 0;
	for (var i = 1; i <= NUM_BANNER_LOCATIONS; i++){//for every banner location
		snippetArray[i] = new Array();//create 2 dimensional array
		for (var e = 0; e < bannerArray.length; e++){//for every banner
			if (i == parseInt(bannerArray[e].bannerlocation)){//if this banner belongs in the current location
				snippetArray[i][eIndex] = bannerArray[e];
				eIndex++;}//using eIndex instead of e eliminates gaps in the array
		}
		eIndex = 0;
	}
}
	
function getNumberOfBanners(){
//this finds the number of banner locations being used
	var maxNum = 0;
	for (var i = 0; i < bannerArray.length; i++){
		if (parseInt(bannerArray[i].bannerlocation) > maxNum)
			maxNum = bannerArray[i].bannerlocation;
	}
	return maxNum;
}

function RotateBanners(){
	for (var i = 1; i <= NUM_BANNER_LOCATIONS; i++){//for every banner location
		var BannerID = "banner" + i;//the banner ID that will be replaced
		cb = bannerArray[i];//bannerArray now hold the current banner for each location
		if (snippetArray[i].length > 1 ){//only rotate the banner if there is more than one
			ChangeBanner(BannerID, snippetArray[i][cb].bannerSnippet);
			bannerArray[i] = (bannerArray[i] + 1) % snippetArray[i].length;
		}
	}
}

function ChangeBanner(id, bannerSnippet)
{
	parentDIV = document.getElementById(id);
	oldChild = parentDIV.childNodes[0];
	newChild = document.createElement('div');
	newChild.innerHTML = bannerSnippet;
	parentDIV.replaceChild(newChild, oldChild);
}

function pickRandom(banLocation, ID)
{
/*'banLocation' is the banner location where a random banner will be chosen from
  if '0' is used, a random banner will be chosen from all avaiable locations*/
/*'ID' is the banner location where the random banner will be displayed*/
NUM_BANNER_LOCATIONS = getNumberOfBanners();
build2DArray();

if (banLocation <= 0 || banLocation > NUM_BANNER_LOCATIONS)
	//randomly choose a banner location between 1 and the number of banner locations
	var randBannerLocation = Math.floor(Math.random() * NUM_BANNER_LOCATIONS ) + 1;
else
	randBannerLocation = banLocation;	
//randomly choose a banner from the location chosen above
var randBanner = Math.floor(Math.random() * snippetArray[randBannerLocation].length);
ChangeBanner(ID, snippetArray[randBannerLocation][randBanner].bannerSnippet);//display the banner
}

function initializeBanners(){
//this sets the div's to their initial banner
	NUM_BANNER_LOCATIONS = getNumberOfBanners();
	build2DArray();
	
	for (var i = 1; i <= NUM_BANNER_LOCATIONS; i++){//for every banner location
		var ID = "banner" + i;//the banner ID that will be replaced
		ChangeBanner(ID, snippetArray[i][0].bannerSnippet);//this sets the initial banner
	}
	//because bannerArray is no longer needed at this point, it will be used to contain the current banner information
	for (var i = 1; i <= NUM_BANNER_LOCATIONS; i++){//for every banner location
		bannerArray[i] = 0;//the new current banner is the next banner in the array
		bannerArray[i] = (bannerArray[i] + 1) % snippetArray[i].length;
	}
		
	setInterval("RotateBanners()",slideshowInterval * 1000);
}