$('#document').ready(function(){
	var scrolling = null;
	//scroll
	$('#g_scroll_down').mousedown(function(){
		scroll_down();
	});
	$('#g_scroll_up').mousedown(function(){
		scroll_up();
	});
	
	$('#g_scroll_down').mouseup(function(){
		stop_scroll();
	});
	$('#g_scroll_up').mouseup(function(){
		stop_scroll();
	});
	
	//click on a thumb
	$('#thumbs_li_inside img').click(function(){
		//capturare the thumb id and generate the identifier
		var img = $(this).attr('alt');
		var dir = $('#iw_gallery').val();
		img = dir+'/'+img;
		$('#gallery_placeholder').attr('src',img);
	});
});

function scroll_up(){
    var d = document.getElementById('thumbs_li');
    d.scrollTop = d.scrollTop - 50;
    scrolling = window.setTimeout(function() {
        scroll_up();
    }, 100);
}

function scroll_down(){
    var d = document.getElementById('thumbs_li');
    d.scrollTop = d.scrollTop + 50;
    scrolling = window.setTimeout(function() {
        scroll_down();
    }, 100);
}

function stop_scroll(){
	window.clearTimeout(scrolling);
}