define(['jquery'], function($) {
	
	var PageLoader = {		

		blockUI : function() {
			var $block = $("<div/>").attr('id','blocked-ui').appendTo('body').fadeIn();
			$block.data('tick', 1);

			// tick clock every half second
			tick = setInterval(function() {				
				var current = $block.data('tick'),
					next    = current += 1;

				// loop to first after 4
				if (next > 4) {
					next = 1;
				};

				// set class and data for next pass
				$block.removeClass().addClass('tick' + next);
				$block.data('tick', next);

			}, 500);
		},

		unblockUI : function() {
			clearInterval(tick);
			$("#blocked-ui").fadeOut(250, function() { $(this).remove() } );
		},

		beforeUnload : function() {
			// show empty loader before reloading
			// todo?
		}

	}

	// attach page switch event
	// PageLoader.switchSite();

	// attach on before unload event
	// PageLoader.beforeUnload();

	// return object method
	return PageLoader;

});