/**
 * ScrollObject: Scroll div contents with Javascript - http://germ.wordpress.com/2006/04/10/scroll-div-contents-with-javascript/
 *
 *  usage: put this after the scrollbox div:  var div_scroll1 = new ScrollObject('div_scroll1', 'scroll_box');
 *
 */


function ScrollObject(scrollname, div_name, up_name, down_name)
{
	this.div_name = div_name;
	this.name = scrollname;
	this.scrollCursor = 0;
	this.speed = 10;
	this.timeoutID = 0;
	this.div_obj = null;
	this.up_name = up_name;
	this.dn_name = down_name;

	{
		if (document.getElementById)
		{
			div_obj = document.getElementById(this.div_name);
			if (div_obj)
			{
				this.div_obj = div_obj;
				this.div_obj.style.overflow = 'hidden';
			}
			div_up_obj = document.getElementById(this.up_name);
			div_dn_obj = document.getElementById(this.dn_name);
			if (div_up_obj && div_dn_obj)
			{
				div_up_obj.onmouseover = function() { eval(scrollname + ".scrollUp();") };
				div_up_obj.onmouseout = function() { eval(scrollname + ".stopScroll();") };
				div_dn_obj.onmouseover = function() { eval(scrollname + ".scrollDown();") };
				div_dn_obj.onmouseout = function() { eval(scrollname + ".stopScroll();") };
			}
		}
	}

	this.stopScroll = function()
	{
		clearTimeout(this.timeoutID);
	}

	this.scrollUp = function()
	{
		if (this.div_obj)
		{
//SL add
			if (this.div_obj.scrollTop!=this.scrollCursor) this.scrollCursor = this.div_obj.scrollTop;
//SL end
			this.scrollCursor = (this.scrollCursor - this.speed) < 0 ? 0 : this.scrollCursor - this.speed;
			this.div_obj.scrollTop = this.scrollCursor;
			this.timeoutID = setTimeout(this.name + ".scrollUp()", 60);
		}
	}

	this.scrollDown = function()
	{
		if (this.div_obj)
		{
//SL add
			if (this.div_obj.scrollTop!=this.scrollCursor) this.scrollCursor = this.div_obj.scrollTop;
//SL end
			this.scrollCursor += this.speed;
			this.div_obj.scrollTop = this.scrollCursor;
			this.timeoutID = setTimeout(this.name + ".scrollDown()", 60);
		}
	}

	this.resetScroll = function()
	{
		if (this.div_obj)
		{
			this.div_obj.scrollTop = 0;
			this.scrollCursor = 0;
		}
	}
}