function setupPhotoGallery() {
	
	function getImages() {
		return $$('#image-container .gallery img');
	}
	
	function getIndexOf(image) {
		var images = getImages();
		for (var i = 0; i < images.length; i++) {
			if (images[i] == image) return i;
		}
	}

	function getActiveIndex() {
		var active = $$('#image-container .gallery img.active')[0];
		return getIndexOf(active);
	}
	
	function showImageAt(index) {
		var images = getImages();
		var currentImage = images[getActiveIndex()];
		var newImage = images[index];		
		
		// hide current image, and show new image
		currentImage.removeClassName('active');
		newImage.addClassName('active');
		
		// display the new image's caption
		$('caption').innerHTML = newImage.title;
		
		// update the number displayed ("1 of 10")
		$$('#photo-number span')[0].innerHTML = index + 1;
		
		// show/hide the "prev" & "next" buttons when at either end of gallery
		$('prev-btn').show();
		$('next-btn').show();
		if (index == 0) $('prev-btn').hide();
		if (index == getImages().length - 1) $('next-btn').hide();
	}
	
	$('prev-btn').hide();

	$('prev-btn').observe('click', function(e) {
		var newIndex = getActiveIndex() - 1;
		if (newIndex >= 0) showImageAt(newIndex);
		Event.stop(e);
	});

	$('next-btn').observe('click', function(e) {
		var newIndex = getActiveIndex() + 1;
		if (newIndex < getImages().length) showImageAt(newIndex);
		Event.stop(e);
	});
	
}