var waitTime = 6000;
var fadeTime = 300;
//SLIDESHOW for Arrild Privatskole
//Copyright Anders Riggelsen - 2009

var currentImage;
var currentImageIndex = 0;
var images = Array();
var timer;
var tempTimer = 0;
var slideshow = null;
function loadSlideShow()
{
	slideshow = document.getElementById('slideshow');
	if(slideshow == null)
		return;
	var content = slideshow.childNodes;
	for( var i in content )
	{
		var image = content[i];
		if(image.nodeName != 'IMG')
			continue;
		images.push(image);
		var preload = new Image(1,1); 
		preload.src = image.src;
	}
	if(images.length == 0)
		return;
	
	currentImage = images[currentImageIndex];
	
	slideshow.style.background = '#fff url('+ currentImage.src +') no-repeat';
	
	setOpacity(currentImage,1);
	currentImage.style.visibility = "visible";
	currentImage.style.display = "block";
	
	var nextImageIndex = (currentImageIndex+1)%images.length;
	timer = setTimeout('startFade('+nextImageIndex+')',waitTime);
}

function startFade( nextImageIndex )
{
	tempTimer = fadeTime;
	slideshow.style.background = '#fff url('+ currentImage.src +') no-repeat';
	
	currentImage.style.visibility = "hidden";
	currentImage.style.display = "none";
	setOpacity(currentImage,0);
	
	currentImageIndex = nextImageIndex;	
	currentImage = images[nextImageIndex];

	setOpacity(currentImage,0);
	currentImage.style.visibility = "visible";
	currentImage.style.display = "block";
	fade();
}

function fade()
{
	if(tempTimer>0)
	{
		tempTimer -= 5;
		setOpacity( currentImage, (1.0-tempTimer/(fadeTime*1.0)) );
		timer = setTimeout('fade()',5);
	}
	else
	{
		var nextImageIndex = (currentImageIndex+1)%images.length;
		slideshow.style.background = '#fff url('+ currentImage.src +') no-repeat';
		timer = setTimeout('startFade('+nextImageIndex+')',waitTime);
	}
}

function setOpacity(object,opacity)
{
	object.style.opacity = opacity;
	object.style.filter = 'alpha(opacity=' + Math.round(opacity*100) + ')';
}

function slideshow_next()
{
	clearTimeout(timer);
	var nextImageIndex = (currentImageIndex+1) % images.length;
	startFade(nextImageIndex);
}

function slideshow_prev()
{
	clearTimeout(timer);
	var nextImageIndex = currentImageIndex-1;
	if(nextImageIndex<0)
		nextImageIndex = images.length-1;
	startFade(nextImageIndex);
}

function slideshow_showNavigation()
{
	var nav = document.getElementById('slideshow_navigation');
	nav.style.visibility = "visible";
	nav.style.display = "block";
}

function slideshow_hideNavigation()
{
	var nav = document.getElementById('slideshow_navigation');
	nav.style.visibility = "hidden";
	nav.style.display = "none";
}