var rightInterval = null;
var leftInterval = null;

function InitGalleryControls()
{
	if($('main').getElementsByClassName('gallery').length <= 0)
	{
		return;
	}

	var btns_scrollLeft = $('main').getElementsByClassName('gallery_scroll_left');
	var btns_scrollRight = $('main').getElementsByClassName('gallery_scroll_right');
	
	for(var i = 0; i < btns_scrollLeft.length; i++)
	{
		Event.observe(btns_scrollLeft[i], 'mouseover', StartScrollLeft);
		Event.observe(btns_scrollLeft[i], 'mouseout', StopScrollLeft);
	}
	
	for(var j = 0; j < btns_scrollRight.length; j++)
	{
		Event.observe(btns_scrollRight[j], 'mouseover', StartScrollRight);
		Event.observe(btns_scrollRight[j], 'mouseout', StopScrollRight);
	}
}

function StartScrollRight(Evt)
{
	if(leftInterval != null)
	{
		return;
	}
	
	var elem = $(Event.element(Evt)).up('.gallery');
	
	var scrollRightFunc = function()
	{
		ScrollRight(elem.id);
	}
	
	rightInterval = window.setInterval(scrollRightFunc, 10);
}

function StopScrollRight()
{
	window.clearInterval(rightInterval)
	rightInterval = null;
}

function ScrollRight(GalleryId)
{	
	var galleryTable = $(GalleryId);
	var container = galleryTable.getElementsByClassName('gallery-container')[0];
	var containerWidth = $(container).getWidth();
	var maxScroll = parseInt((containerWidth - 400) * (-1));
	
	if((container.style.marginLeft != null) && (parseInt(container.style.marginLeft.replace(/px/, '')) <= maxScroll))
	{
		return;
	}
	
	if((container.style.marginLeft != null) && (container.style.marginLeft != ''))
	{
		container.style.marginLeft = parseInt(container.style.marginLeft.replace(/px/, '')) - 2 + 'px';
	}
	else
	{
		container.style.marginLeft = '-2px';
	}
}

function StartScrollLeft(Evt)
{
	if(rightInterval != null)
	{
		return;
	}
	
	var elem = $(Event.element(Evt)).up('.gallery');
	
	var scrollLeftFunc = function()
	{
		ScrollLeft(elem.id);
	}
	
	leftInterval = window.setInterval(scrollLeftFunc, 10);
}

function StopScrollLeft()
{
	window.clearInterval(leftInterval)
	leftInterval = null;
}

function ScrollLeft(GalleryId)
{
	var galleryTable = $(GalleryId);
	var container = galleryTable.getElementsByClassName('gallery-container')[0];
	
	if((container.style.marginLeft != null) && (parseInt(container.style.marginLeft.replace(/px/, '')) >= 0))
	{
		return;
	}
	
	if((container.style.marginLeft != null) && (container.style.marginLeft != ''))
	{
		container.style.marginLeft = parseInt(container.style.marginLeft.replace(/px/, '')) + 2 + 'px';
	}
	else
	{
		container.style.marginLeft = '+2px';
	}
}

Event.observe(window, 'load', InitGalleryControls);