/*	The following script is based on a blog post entitled "Onload image fades without flash",
	written by Richard Rutter. It can be found on http://clagnut.com/sandbox/imagefades/ (08/01/07).
	Marco Tresch */

window.onload = function() {playSlideShow(0)}

var pictures = new Array("partynights.jpg", "oktoberfest_08-1.jpg", "oktoberfest_08-2.jpg", "whirlpool24.jpg");
var urls = new Array("http://www.partynights.ch", "http://www.oktoberfest.sh", "http://www.oktoberfest.sh", "http://www.whirlpool24.ch");
var imDir = "img/logos/rotation/";
var imId1 = "bild1";
var imId2 = "bild2";
var delay = 2000;

function playSlideShow(offset) {
    pathNOW = imDir+pictures[offset];
    pathLAST = imDir+pictures[offset-1];

    nr = offset;
    if (nr == 0) {
		  // Erstes Bild anzeigen
	    showImage(pathNOW, imId2, nr);
		  setTimeout('playSlideShow(nr+1)', delay*2);		
	  }
	  else if (nr < pictures.length) {
	   	// Nächstes Bild anzeigen
	 	  clearImage(pathLAST, imId2);
	    showImage(pathNOW, imId1, nr);
		  setTimeout('playSlideShow(nr+1)', delay);
	  }
	  else {
	    // Letztes Bild ausplenden, Slideshow von vorne beginnen
	 	  clearImage(pathLAST, imId2);
		  setTimeout('playSlideShow(0)', delay);
	  }
}

function showImage(imageSrc, imageId, nr) {
  holder = document.getElementById('photoholder');
  holder.setAttribute("onClick", "location.href='" + urls[nr] + "'");
  image = document.getElementById(imageId);
	image.style.visibility = 'visible';
  image.src = imageSrc;
  setOpacity(image, 0);
  fadeIn(imageId,0);	
}

function clearImage(imageSrc, imageId) {
  image = document.getElementById(imageId);
	image.style.visibility = 'visible';
  image.src = imageSrc;
  setOpacity(image, 100);
  fadeOut(imageId,100);	
}

function setOpacity(obj, opacity) {
  opacity = (opacity == 100)?99.999:opacity;
  
  // IE/Win
  obj.style.filter = "alpha(opacity:"+opacity+")";
  
  // Safari<1.2, Konqueror
  obj.style.KHTMLOpacity = opacity/100;
  
  // Older Mozilla and Firefox
  obj.style.MozOpacity = opacity/100;
  
  // Safari 1.2, newer Firefox and Mozilla, CSS3
  obj.style.opacity = opacity/100;
}

function fadeIn(objId,opacity) {
  if (document.getElementById) {
    obj = document.getElementById(objId);
    if (opacity <= 100) {
      setOpacity(obj, opacity);
      opacity += 10;
      window.setTimeout("fadeIn('"+objId+"',"+opacity+")", 100);
    }
  }
}

function fadeOut(objId,opacity) {
  if (document.getElementById) {
    obj = document.getElementById(objId);
    if (opacity >= 0) {
      setOpacity(obj, opacity);
      opacity -= 10;
      window.setTimeout("fadeOut('"+objId+"',"+opacity+")", 100);
    }
		if (opacity < 1) { obj.style.visibility = 'hidden'; }		// IE Bug
  }
}