/*
*********************************************************************************************
*											    *
*	Scrolling Layer Function							    *
*	Author: BPPR									    *
*											    *
*	Usage:										    *
*											    *
*	layerScroll(layer, maxTop, MaxBottom, direction)		 		    *
*											    *
*	layer = the layer name that is going to be moved				    *
*	maxTop = pixel position (top) of layer when top is reached			    *
*	maxBottom = pixel position (top) of layer when bottom is reached		    *
*	direction = up or down								    *
*											    *
*	Notes:										    *
*	The movement effect needs to layers be implemented.  One layer that only shows	    *
*	part of the layer being moved and the layer to be moved.  Layer names should be as  *
*	follows:									    *
* 											    *
*	The layer that hides the rest of the data on the layer to be moved should be named  *
*	exactly the same as the layer to be moved but with a "B" added at the end.	    *
*											    *
* 	if layer to be moved = layer							    *
*	then showing layer should be layerB						    *
*											    *
*********************************************************************************************
*/

var scrolling
var isNav, isNav6, isIE

if (navigator.appName == "Netscape" && navigator.appVersion.substring(0,3) == "4.7")
{
	isNav = true
}

else if (navigator.appVersion.indexOf("MSIE") != -1)
{
	isIE = true
}

else if(navigator.appName == "Netscape" && navigator.appVersion.substring(0,3) == "5.0")
{
	isNav6 = true
}

function layerScroll(layer, maxTop, maxBottom, direction)
{
    var page;
    var t;

    if(isIE)
    {
    	eval("page = document.all." + layer + ".style");
    	t = parseInt(eval("page.top"));
    }
    else if(isNav)   
    {
    	eval("page = document." + layer + "B.document." + layer);
    	t = parseInt(eval("page.top"));
    }
    else if(isNav6)
    {
	page = document.getElementById(layer)
    	t = parseInt(page.style.top);
    }	
 	if (direction == "up")
 	{
		if (t > maxBottom)
		{		
			if(isIE || isNav)
			{
				eval("page.top = " + t + " - 3"); 
				scrolling = setTimeout("layerScroll('" + layer + "', " + maxTop + ", " + maxBottom + ", 'up')", 1)		
			}

			else if(isNav6)
			{
				t = t - 3;
				page.style.top = t + "px";
				scrolling = setTimeout("layerScroll('" + layer + "', " + maxTop + ", " + maxBottom + ", 'up')", 1)		
			}	
		}
		else
		{}	
	}
 	else
 	{
		if (t < maxTop)
		{
			if(isIE || isNav)
			{
				eval("page.top = " + t + " + 3");
				scrolling = setTimeout("layerScroll('" + layer + "', " + maxTop + ", " + maxBottom + ", 'down')", 1)
			}

			else if(isNav6)
			{	
				t = t + 3;		
				page.style.top = t + "px";
				
				scrolling = setTimeout("layerScroll('" + layer + "', " + maxTop + ", " + maxBottom + ", 'down')", 1)
			}
		}	
		else
		{}
	}		
}

function layerGo(layer, position)
{
    var page;
    
    if(isIE)
    {
    	eval("page = document.all." + layer + ".style");
    	eval("page.top = " + position); 			
    }
    else if(isNav)  
    {
    	eval("page = document." + layer + "B.document." + layer);
    	eval("page.top = " + position); 			
    }
    else if(isNav6)
    {
	page = document.getElementById(layer);
	page.style.top = position + "px";
    }
}


function stop()
{
  clearTimeout(scrolling);
}