document.observe('dom:loaded', function(){
	var running = false;
	var maxSpeed = 3;
	var collectionWidth = 0;
	var collectionVector = 0;
	var set1 = $('videoCollection');
	var set2 = $('videoCollection2');
	var ieOffset = 0;
	var set1StartOffset = -125;
	if(Prototype.Browser.IE)
		ieOffset = 5;
	$$('#videoCollection div.videoThumb').each(function(elm){
		collectionWidth += Element.getWidth(elm) + parseInt(elm.getStyle("marginLeft")) + parseInt(elm.getStyle("marginRight"));
	});
	var set2StartOffset = collectionWidth + ieOffset*2 + set1StartOffset;
	set1.setStyle({width: collectionWidth + ieOffset + 'px', left: set1StartOffset + 'px'});
	set2.setStyle({width: collectionWidth + ieOffset + 'px', left: set2StartOffset - ieOffset*2 + 'px'});
	var videoContainerWidth = Element.getWidth('videoContainer');
	
	function moveVideos(vector) {
		var currentLeft1 = parseFloat(set1.getStyle('left'));
		var currentLeft2 = parseFloat(set2.getStyle('left'));
		if(vector < 0) {
			if(currentLeft1 + Element.getWidth(set1) < 0){
				currentLeft1 = currentLeft2 + Element.getWidth(set2) - ieOffset*2;
				set1.setStyle({left: currentLeft1 + 'px'});
			}
			if(currentLeft2 + Element.getWidth(set2) < 0){
				currentLeft2 = currentLeft1 + Element.getWidth(set1) - ieOffset*2;
				set2.setStyle({left: currentLeft2 + 'px'});
			}
		} else {
			if(currentLeft1 > videoContainerWidth){
				currentLeft1 = currentLeft2 - Element.getWidth(set1) + ieOffset*2;
				set1.setStyle({left: currentLeft1 + 'px'});
			}
			if(currentLeft2 > videoContainerWidth){
				currentLeft2 = currentLeft1 - Element.getWidth(set2) + ieOffset*2;
				set2.setStyle({left: currentLeft2 + 'px'});
			}
		}
		//$('categories').update((currentLeft1) + ' ' + (currentLeft2));
		//$('categories').update((currentLeft1+vector) + ' ' + (currentLeft2+vector));
		set1.setStyle({left: (currentLeft1 + vector) + 'px'});
		set2.setStyle({left: (currentLeft2 + vector) + 'px'});
	}
	
	$('leftArrow').observe('mouseover', function(e){
		collectionVector = maxSpeed;
		running = true;
	});
	$('leftArrow').observe('mouseout', function(e){
		running = false;
	});
	$('rightArrow').observe('mouseover', function(e){
		collectionVector = -maxSpeed;
		running = true;
	});
	$('rightArrow').observe('mouseout', function(e){
		running = false;
	});
	
	new PeriodicalExecuter(function(pe) {
		if(collectionVector != 0){
			moveVideos(collectionVector);
			if(!running) {
				if(Prototype.Browser.IE) {
					collectionVector = 0;
				} else {
					collectionVector *= 0.9;
					if(Math.abs(collectionVector) < 0.01) {
						collectionVector = 0;
					}
				}
			}
		}
	}, 0.01);
});