var MaxBanners          = -1;
var CurrentBanner 		= 0;
var Delay               = 9;
var TimeoutInstance 	= null;

function GetMaxBanners()
{
	if(MaxBanners == -1)
	{
	    for(ct = 0; ct < 10; ct++)
	    {
			if(document.getElementById("b" + ct) == null)
			{
				MaxBanners = ct;
				break;
			}
	    }
	}

	return MaxBanners;
}

function GetPreviousBannerIndex()
{
	var NewBannerID = CurrentBanner - 1;
	if(NewBannerID < 0)
		NewBannerID = GetMaxBanners() - 1;

	return NewBannerID;
}

function GetNextBannerIndex()
{
	var NewBannerID = CurrentBanner + 1;
	NewBannerID = NewBannerID % GetMaxBanners();

	return NewBannerID;
}

function NavigateBanner(BannerIndex)
{
    clearTimeout(TimeoutInstance);
	return ChangeBanners(BannerIndex);
}

function ChangeBanners(bannerIndex)
{
    var OldBanner	= document.getElementById("b" + CurrentBanner);
	var NewBanner	= document.getElementById("b" + bannerIndex);

	OldBanner.style.display = "none";
	NewBanner.style.display = "block";
	
	CurrentBanner	= bannerIndex;

	AutoPlayNextBanner();

	return false;
}

function MovePrevBanner()
{
	NavigateBanner(GetPreviousBannerIndex());
}
function MoveNextBanner()
{
	NavigateBanner(GetNextBannerIndex());
}

function AutoPlayNextBanner(Timer)
{
	if(Timer == null)
		Timer = Delay;
	else Delay = Timer;
		
	TimeoutInstance = setTimeout("ChangeBanners(" + GetNextBannerIndex() + ")", Timer * 1000);
}