/* scroll.js */
/*

*/

var orginalpos = null;
var pos = null;
var height = null;
var factor = null;
var DimensionsElement = "inthemiddle";
var DimensionsElementViewPort = "content";


Event.observe(window, 'load', function() {
	GetDimensions();
	Event.observe(window, 'resize', GetResizedDimensions);
});


function GetDimensions()
{
	element = DimensionsElement;
	
	pos = originalpos = $(element).positionedOffset()[1];
	height = $(element).getHeight();
	vpheight = $(element).getOffsetParent().getOffsetParent().getHeight();
	factor = Math.ceil(height / Math.ceil(height / vpheight));
	
	/*
	s = "pos: "+pos+"\nheight: "+height+"\nvpheight: "+vpheight+"\nfactor: "+factor;
	alert (s);
	*/
}


function GetResizedDimensions()
{
	element = DimensionsElement;
	
	vpheight = $(element).getOffsetParent().getOffsetParent().getHeight();
	factor = Math.ceil(height / Math.ceil(height / vpheight));
}


function movedown(element)
{
	pos = $(element).positionedOffset()[1];

	if (pos < originalpos)
	{
		new Effect.Move($(element), { x: 0, y: factor, mode: 'relative' });
		pos += factor;
	}
}


function moveup(element)
{
	pos = $(element).positionedOffset()[1];
	
	if (pos + height > originalpos + factor)
	{
		new Effect.Move($(element), { x: 0, y: -factor, mode: 'relative' });
		pos -= factor;
	}
}