// Extension developed by David G. Miles 
// Original Scrollable Area code developed by Thomas Brattli 
function verifyCompatibleBrowser(){ 
    this.ver=navigator.appVersion 
    this.dom=document.getElementById?1:0 
	this.ie5=((this.ver.indexOf("MSIE 5")>-1 || this.ver.indexOf("MSIE 6")>-1) && this.dom)?1:0; 
    this.ie4=(document.all && !this.dom)?1:0; 
    this.ns5=(this.dom && parseInt(this.ver) >= 5) ?1:0; 
    this.ns4=(document.layers && !this.dom)?1:0; 
    this.bw=(this.ie5 || this.ie4 || this.ns4 || this.ns5) 
    return this ;
} 

var bw=new verifyCompatibleBrowser();
var speed=50;
 
var loop, timer;
var initialised; 
var objContainer,objScroller;

function ConstructObject(obj,nest){ 
    nest=(!nest) ? '':'document.'+nest+'.';
    this.el=bw.dom?document.getElementById(obj):bw.ie4?document.all[obj]:bw.ns4?eval(nest+'document.'+obj):0;
    this.css=bw.dom?document.getElementById(obj).style:bw.ie4?document.all[obj].style:bw.ns4?eval(nest+'document.'+obj):0;
    this.scrollHeight=bw.ns4?this.css.document.height:this.el.offsetHeight;
    this.clipHeight=bw.ns4?this.css.clip.height:this.el.offsetHeight;
    this.up=MoveAreaUp;this.down=MoveAreaDown; 
    this.MoveArea=MoveArea;
	this.x; 
	this.y; 
    this.obj = obj + "Object";
    eval(this.obj + "=this");
    return this;
}

function MoveArea(x,y){ 
   this.x=x;this.y=y;
   this.css.left=this.x;
   this.css.top=this.y;
} 
 
function MoveAreaDown(move){
	if(bw.ie5 || bw.ie4) {
		if(this.y>-parseInt(divContent.style.height)+objContainer.clipHeight) {
    		this.MoveArea(0,this.y-move);
	    	if(loop) setTimeout(this.obj+".down("+move+")",speed);
		} 
		
	} else {
		if(this.y>-this.scrollHeight+objContainer.clipHeight) { 
    		this.MoveArea(0,this.y-move);
	    	if(loop) setTimeout(this.obj+".down("+move+")",speed);
		} 
 	}
}

function MoveAreaUp(move){ 
		if(this.y<0) {
    		this.MoveArea(0,this.y-move);
		    if(loop) 
				setTimeout(this.obj+".up("+move+")",speed);
		}
} 
 
function PerformScroll(speed){

	if(initialised){ 
		loop=true; 
		if(speed>0){
		 objScroller.down(speed);
		}
		else {
		objScroller.up(speed);
		}
	} 
} 
 
function CeaseScroll(){ 
    loop=false;
    if(timer) clearTimeout(timer);
} 

function InitialiseScrollableArea(){ 
	objContainer = new ConstructObject('divContainer');
    objScroller=new ConstructObject('divContent','divContainer');
    objScroller.MoveArea(0,0);
    objContainer.css.visibility='visible';
    initialised=true; 
    
} 
// end absolutely positioned scrollable area object scripts