$(function(){
	
	(function($){

		$banner_area = $("#banner_area");
		$banner_area_items = $(".banner_item", $banner_area);
		$banner_no_of_elements = $banner_area_items.size(); 
		$banner_current_element = 0; 
		
		function slider(options, element) { 
			var defaults = {
				speedOverlayUp: 0,
				speedOverlayDown: 0,
				speedOverlayWait: 0,
				speedFadeOut: 200
			}; 
			var options = $.extend(defaults, options); 
			     
			var $currentObj = $(element);
			var $overlay = $(".overlay", $currentObj); 
			var animateSliderStart = function(){
				return $overlay
					.animate({
						bottom: 0
					}, options.speedOverlayUp)
					.delay(5000) 
					.queue(function(n) { 
						$overlay.animate({
							bottom: "-75px"
						}, options.speedOverlayDown,
							function(){
								$currentObj.css("zIndex", 100);
								showNextItem();
								$currentObj.fadeOut(options.speedFadeOut, function(){
									slider( options, $($banner_area_items[$banner_current_element]) );
									$currentObj.css("zIndex", 1);
								});
							}
						)
					})
					.dequeue();
			} 
			var showNextItem = function() {
				$banner_current_element++;  
				if ($banner_current_element == $banner_no_of_elements) { 
					$banner_current_element = 0; 
				}
				$($banner_area_items[$banner_current_element]).css("zIndex", 1).show(); 
			}
			
			// start animation for current slider 
			animateSliderStart();  
		}; 
		
		function doSlider($element) {
			slider({
				speedOverlayUp: 1500,
				speedOverlayDown: 1000,
				speedOverlayWait: 3000,
				speedFadeOut: 1000
			}, $element);
		}
		doSlider($(".visible", $banner_area));
		
	})(jQuery);  
	
})