var repeatRate = 3000; // Change every three seconds

var bigHeight = 0;
var adId = 0;

function StartAdvertRotation()
{
	// Precache images and get largest
	for (var i = 0; i < advert.length; i++)
	{
	        var tmp = new Image();
	        tmp.src = advert[i][1];
	        
	        if (tmp.height > bigHeight)
	        	bigHeight = tmp.height;

	        advert[i][2] = tmp;
	}
	
	// Start at random advert
	adId = Math.floor(Math.random() * advert.length);
	
	// Start
	RotateAdvert();
}

function RotateAdvert()
{
        // Get layer element
        var el = document.getElementById('advert');

        if (el != null)
        {
                // Clear children
                for (var i = 0; i < el.childNodes.length; i++)
                        el.removeChild(el.childNodes[i]);

                // Create link
                var link = document.createElement('a');
                link.href = advert[adId][0];

                // Create and add image
                var adImg = document.createElement('img');
                adImg.src = advert[adId][1];
                adImg.style.borderWidth = 0;
                link.appendChild(adImg);
                
                // Add link
                el.appendChild(link);
                
		        if (adImg.height > bigHeight)
		        	bigHeight = adImg.height;
				el.style.height = bigHeight + 'px';
        }

        /* Repeat after delay */
        setTimeout("RotateAdvert()", repeatRate);

        adId = (++adId % advert.length);
}

function CheckImageSize(img)
{
        // Get layer element
        var el = document.getElementById('advert');

        if (el != null)
        {
		        if (img.height > bigHeight)
		        	bigHeight = img.height;
				el.style.height = bigHeight + 'px';
        }
}