/**
 * @author yuval_raz
 */
onload = function(){
	var main_content, scrollable, scroll_up, scroll_down, scroll_location_bottom, scroll_height;
	main_content = document.getElementById("main_content");
	scrollable = document.getElementById("scrollable");
	scroll_up = document.getElementById("scroll_up");
	scroll_down = document.getElementById("scroll_down");
	scroll_height = scrollable.offsetHeight;
	var i = 0;
	function scroll_it_up(){
		scrollable.style.top = i  + 'px';
		if (i == scroll_height){
			return;
		}
		else{i++;i++;}
	}
	scroll_up.onmouseover = function(){
	   if(this.timer==null){
	     this.timer = setInterval(scroll_it_up, 10);
	   }
	}
	scroll_up.onmouseout = function(){ clearTimeout(this.timer); this.timer=null; }

	function scroll_it_down(){
		scrollable.style.top = i  + 'px';
		if (i == scroll_height){
			return;
		}
		else{i--;i--}
	}
	scroll_down.onmouseover = function(){
	   if(this.timer==null){
	     this.timer = setInterval(scroll_it_down, 10);
	   }
	}
	scroll_down.onmouseout = function(){ clearTimeout(this.timer); this.timer=null; }
}