$(document).ready(function() { //perform actions when DOM is ready
	
  $('.card01').css({'display' : 'block'});
  
  var z = 0; //for setting the initial z-index's
  var inAnimation = false; //flag for testing if we are in a animation
    
  $('#biz-cards img').each(function() { //set the initial z-index's
    z++; //at the end we have the highest z-index value stored in the z variable
    $(this).css('z-index', z); //apply increased z-index to <img>
  });
  
  setInterval(function() { //interval every 1 second
	swapFirstLast(true); //execute next action
  }, 4000); //1000 = 1 sec
  
  function swapFirstLast(isFirst) {
    if(inAnimation) return false; //if already swapping pictures just return
    else inAnimation = true; //set the flag that we process a image

    var processZindex, direction, newZindex, inDeCrease; //change for previous or next image

    if(isFirst) { processZindex = z; direction = '-'; newZindex = 1; inDeCrease = 1; } //set variables for "next" action
    else { processZindex = 1; direction = '-'; newZindex = z; inDeCrease = -1; } //set variables for "previous" action

    $('#biz-cards img').each(function() { //process each image
        
      if($(this).css('z-index') == processZindex) { //if its the image we need to process
      	
      	if ($(this).next('.case').is('.card06')) {
      			$('.case').fadeOut(200);
        		$('.card01').fadeIn(500);
        	}
        	else {
        		$('.case').fadeOut(200); // hide previously visible description
        		$(this).prev('.case').fadeIn(500); // show next description
    	   	} 
    	   	
        $(this).animate({ 'left' : direction + $(this).width() + 'px' }, 'medium', function() { //animate the img above/under the gallery (assuming all pictures are equal width)
        
        	
          $(this).css('z-index', newZindex) //set new z-index
            .animate({ 'left' : '0' }, 'medium', function() { //animate the image back to its original position
              inAnimation = false; //reset the flag
            });
        });
      } else { //not the image we need to process, only in/de-crease z-index
        $(this).animate({ 'left' : '0' }, 'medium', function() { //make sure to wait swapping the z-index when image is above/under the gallery
          $(this).css('z-index', parseInt($(this).css('z-index')) + inDeCrease); //in/de-crease the z-index by one
        });
      }
    });

    return false; //don't follow the clicked link
  }

  $('#next a').click(function() {
    return swapFirstLast(true); //swap first image to last position
  });

  $('#prev a').click(function() {
    return swapFirstLast(false); //swap last image to first position
  });
  
  $('.click').click(function() {
    return swapFirstLast(true); //swap first image to last position
  });
});