var currentImg=1;

var effectInProgress=false;


window.onload=function()
{
	if (document.getElementById('boxScrollTrack')!=null && document.getElementById('boxScroll')!=null && document.getElementById('boxScroll').scrollHeight>document.getElementById('boxScroll').offsetHeight)
	{
		document.getElementById('boxScrollTrack').style.display="block";
		
		slider1=new Control.Slider('boxScrollHandle','boxScrollTrack', {axis: 'vertical'});
		
		slider1.options.onSlide = function(value)
		{
			document.getElementById('boxScroll').scrollTop=(document.getElementById('boxScroll').scrollHeight-document.getElementById('boxScroll').offsetHeight)*value;
		}

		slider1.options.onChange = function(value)
		{
			document.getElementById('boxScroll').scrollTop=(document.getElementById('boxScroll').scrollHeight-document.getElementById('boxScroll').offsetHeight)*value;
		}
		
		
		Event.observe('boxScroll', 'DOMMouseScroll', wheel);
			
		Event.observe('boxScroll', 'mousewheel', wheel);		
	}
	
	if (document.getElementById('current')!=null && slider1!=null)
	{
		slider1.setValue(document.getElementById('current').offsetTop/(document.getElementById('boxScroll').scrollHeight-document.getElementById('boxScroll').offsetHeight));
	}
}


function showImage(id)
{
	if (id!=currentImg && !effectInProgress)
	{
		new Effect.Parallel([
		new Effect.Fade("work"+currentImg,{from: 1, to: 0, sync: true}),
		new Effect.Appear("work"+id,{from: 0, to: 1, sync: true}),	
		new Effect.Fade("workThumb"+currentImg,{from: 1, to: 0, sync: true}),
		new Effect.Appear("workThumb"+id,{from: 0, to: 1, sync: true})],
		
		{duration: 1, queue: 'end', beforeStart: function(){effectInProgress=true;}, afterFinish: function(){effectInProgress=false;}});
		
		currentImg=id;
	}
}

function handle(delta)
{
	slider1.setValueBy(-delta/12);
	
	document.getElementById('boxScroll').scrollTop=(document.getElementById('boxScroll').scrollHeight-document.getElementById('boxScroll').offsetHeight)*slider1.value;
	
}

function wheel(event)
{
	var delta = 0;
	
	if (!event)	event = window.event;
	
	if (event.wheelDelta)
	delta = event.wheelDelta/120;
	else if (window.opera) delta = -delta;
	else if (event.detail) delta = -event.detail/3;
	
	if (delta) handle(delta);

	if (event.preventDefault) event.preventDefault();
	
	event.returnValue = false;
}