var current = 1;
var active = false;

function align(el){
	el.setStyle("top", Math.round((810 - el.getHeight()) / 2));
	el.setStyle("left", Math.round((810 - el.getWidth()) / 2));
}
function change(n){
	active = false;
	//$('loading').setStyle('display', 'block');
	
	$('loading').setStyle('opacity', 1);
	nextImage = "fotos-maribingo/" + n.toString() + ".jpg";
	var images = [nextImage];
	var loader = new Asset.images(images, {
		onComplete: function(){
			//$('loading').setStyle('display', 'none');
			$('loading').fade(0);
			if(current % 2 == 0){
				$('nex').set("src", nextImage);
				align($('nex'));
				$('nex').get('tween', {property: 'opacity'}).start(1);
				$('pri').get('tween', {property: 'opacity'}).start(0).chain(function(){
					active = true;
				});
			}else{
				$('pri').set("src", nextImage);
				align($('pri'));
				$('pri').get('tween', {property: 'opacity'}).start(1);
				$('nex').get('tween', {property: 'opacity'}).start(0).chain(function(){
					active = true;
				});
			}
		}
	});
}

window.addEvent('domready', function(){
	$('nex').setStyle('opacity', 0);
	$('nex').setStyle('display', 'block');
	$('loading').setStyle('opacity', 0);
	$('next').addEvent('click', function(ev){
		ev = new Event(ev).stop();
		if(current < 14 && active){
			current++;
			change(current);
		}
	});
	$('prev').addEvent('click', function(ev){
		ev = new Event(ev).stop();
		if(current > 1 && active){
			current--;
			change(current);
		}
	});
});

window.addEvent('load', function(){active = true;});