var TeaserSlider =
{
	numberOfImages : null,
	lastImage : -1,
	
	GetNumberOfImages : function()
	{
		if (this.numberOfImages == null)
		{
			this.numberOfImages = $('.nivoSlider img').length;
		}
		
		return this.numberOfImages;
	},
	
	GetRandomImage : function()
	{
		var randomImage;
		
		do
		{
			randomImage = Math.floor(Math.random() * this.GetNumberOfImages());
		} while (randomImage == this.lastImage);
		
		this.lastImage = randomImage;
		
		return randomImage;
	},
	
	SetNivoRandomNextImage : function(element)
	{
		var nextImage = this.GetRandomImage() - 1;
		$('.nivoSlider').data('nivo:vars').currentSlide = nextImage;
	}
};

$(document).ready(function()
{
	jQuery('.nivoSlider').nivoSlider({
        effect : 'random',
        slices : 15,
        boxCols : 8,
        boxRows : 4,
        animSpeed : Config.teaserSliderFadingTime,
        pauseTime : Config.teaserSliderStandTime,
        startSlide : TeaserSlider.GetRandomImage(), // random start image
        directionNav : true,
        directionNavHide : true,
        controlNav : true,
        controlNavThumbs : false,
        controlNavThumbsFromRel : true,
        keyboardNav : true,
        pauseOnHover : true,
        manualAdvance : false,
		beforeChange : function(element) { TeaserSlider.SetNivoRandomNextImage(element); } // random next image
    });
});