var centerpiece_active = 0;
var centerpiece_delay = 7000;
var centerpiece_loading = false;
var centerpiece_rotating = true;
var centerpiece_timeout = 0;
var centerpieces = new Array();

function centerpiece_advance(reverse)
{
	if (!centerpiece_loading)
	{
		if (reverse)
		{
			if (0 == centerpiece_active)
			{
				var index = centerpieces.length - 1;
			}
			else
			{
				var index = centerpiece_active - 1;
			}
		}
		else
		{
			if (centerpieces.length - 1 == centerpiece_active)
			{
				var index = 0;
			}
			else
			{
				var index = centerpiece_active + 1;
			}
		}
		
		if (centerpiece_rotating && undefined != reverse)
		{
			clearTimeout(centerpiece_timeout);
		}
		
		centerpiece_load(index);
		
		return true;
	}
	
	return false;
}

function centerpiece_load(index)
{
	if (!centerpiece_loading)
	{
		centerpiece_loading = true;
		
		var slideshow = document.getElementById('slideshow');
		var images = slideshow.getElementsByTagName('img');
		var title = slideshow.getElementsByTagName('h2')[0];
		var subtitle = slideshow.getElementsByTagName('h3')[0];
		var description = slideshow.getElementsByTagName('p')[0];
		var link = document.getElementById('link');
		var li = slideshow.getElementsByTagName('li');
		
		var image_on = ('none' == images[0].style.display ? 0 : 1);
		var image_off = ('none' == images[0].style.display ? 1 : 0);
		
		images[image_on].onload = function ()
		{
			this.style.display = '';
			images[image_off].style.display = 'none';
			
			title.innerHTML = centerpieces[index].Centerpieces.title;
			
			if (null == centerpieces[index].Centerpieces.subtitle)
			{
				subtitle.style.display = 'none';
			}
			else
			{
				subtitle.innerHTML = centerpieces[index].Centerpieces.subtitle;
				subtitle.style.display = '';
			}
			
			if (null == centerpieces[index].Centerpieces.description)
			{
				description.style.display = 'none';
			}
			else
			{
				description.innerHTML = centerpieces[index].Centerpieces.description;
				description.style.display = '';
			}
			
			if (null == centerpieces[index].Centerpieces.link)
			{
				link.style.display = 'none';
			}
			else
			{
				link.getElementsByTagName('a')[0].href = centerpieces[index].Centerpieces.link;
				link.style.display = '';
			}
			
			li[centerpiece_active + 1].className = '';
			li[index + 1].className = 'selected';
			
			if (centerpiece_rotating)
			{
				centerpiece_timeout = setTimeout('centerpiece_advance();', centerpiece_delay);
			}
			
			centerpiece_active = index;
			centerpiece_loading = false;
		};
		
		images[image_on].alt = centerpieces[index].Centerpieces.title;
		images[image_on].src = '';
		images[image_on].src = centerpieces[index].Centerpieces.photo.link;
		
		return true;
	}
	
	return false;
}