/* imgfader.js */

function fadeTransition( ndx )
{
	elems = $('imageFader').getElementsByTagName( 'img' );
	iNdx=0;
	
	for( i=0; i < elems.length; i++ )
		if( elems[i].style.display != "none" )
			iNdx=i;
			
	nIdx = (iNdx+1)%elems.length;

	if( ndx >= 5 )
	{
		// Fade up
		
		switch( ndx )
		{
			case 5:
				nOpac=0.2;
				break;
				
			case 6:
				nOpac=0.4;
				break;

			case 7:
				nOpac=0.6;
				break;

			case 8:
				nOpac=0.8;
				break;

			case 9:
				nOpac=1.0;
				break;
		}

		if( ndx == 5 )
		{
			elems[nIdx].style.display = "block";
			elems[iNdx].style.display = "none";
		}

		Element.extend( elems[iNdx] );
		elems[iNdx].setOpacity( nOpac );		
	}
	else
	{
		// Fade down
		switch( ndx )
		{
			case 0:
				nOpac=0.8;
				break;
				
			case 1:
				nOpac=0.6;
				break;

			case 2:
				nOpac=0.4;
				break;

			case 3:
				nOpac=0.2;
				break;

			case 4:
				nOpac=0.0;
				break;
				
			default:
				alert( "Illegal timer!, got "+ndx );
				break;
		}
		
		Element.extend( elems[iNdx] );
		elems[iNdx].setOpacity( nOpac );
	}
	
	if( ndx < 10 )
		setTimeout( "fadeTransition( "+(ndx+1)+")", 50 );
}

function fadeImage()
{
	fadeTransition( 0 );	
	setTimeout( "fadeImage()", 4000 );
}

function initImgFader()
{
	// Walk through the pictures, set display to none for all of them except the first one
	if( $('imageFader'))
	{
		elems = $('imageFader').getElementsByTagName( 'img' );
	
		for( i=1; i < elems.length; i++ )
		{
			elems[i].style.display = "none";
			Element.extend( elems[i] );
			elems[i].setOpacity( 0.0 );
		}
		
		setTimeout( "fadeImage()", 4000 );
	}
}

if (window.addEventListener)
	window.addEventListener("load", initImgFader, false);
else if (window.attachEvent)
	window.attachEvent("onload", initImgFader );