var ad = {};

ad.rotateTimer = null;
ad.liArray = null;

ad.rotateGallery = function()
{
	for ( var i = 0; i<ad.liArray.length; i++ )
	{
		if ( ad.liArray[i].className == 'shown' )
		{
			ad.liArray[i].className = '';
			nextIndex = i + 1;
			if ( nextIndex >= ad.liArray.length ) nextIndex = 0;
			ad.liArray[nextIndex].className = 'shown';
			break;			
		}
	}
}

ad.startRotation = function()
{
	var gallery = document.getElementById('adGallery');
	if (null == gallery) return null;
	ad.liArray = gallery.getElementsByTagName('li');
	if ( 0 == ad.liArray.length ) return;

	var shownFlag = false;
	for ( var i = 0; i<ad.liArray.length; i++ )
	{
		if ( ad.liArray[i].className == 'shown' )
		{
			shownFlag = true;
			break;			
		}
	}
	if ( shownFlag == false ) ad.liArray[0].className = 'shown';

	ad.rotateTimer = setInterval(ad.rotateGallery, 2000);
}

window.onload = ad.startRotation;