/*
Smart Cache Slide Show
Copyright Jason Moon
*/

function CacheImage(ImageSource) { // TURNS THE STRING INTO AN IMAGE OBJECT
   var ImageObject = new Image();
   ImageObject.src = ImageSource;
   return ImageObject;
}

function ShowSlide(Direction) {
   if (SlideReady) {
      NextSlide = CurrentSlide + Direction;
      // THIS WILL DISABLE THE BUTTONS (IE-ONLY)
      document.SlideShow.Previous.className = (NextSlide <= 0) ? 'disabled' : '';
      document.SlideShow.Next.className = (NextSlide >= (Slides.length-1)) ? 'disabled' : '';    
 if ((NextSlide >= 0) && (NextSlide < Slides.length)) {
            document.images['Screen'].src = Slides[NextSlide].src;
            CurrentSlide = NextSlide++;
            Message = 'Picture ' + (CurrentSlide+1) + ' of ' + Slides.length;
            self.defaultStatus = Message;
            if (Direction == 1) CacheNextSlide();
			document.SlideShow.Count.value = (CurrentSlide+1) + '/' + Slides.length;
      }
      return true;
   }
}

function Download() {
   if (Slides[NextSlide].complete) {
      SlideReady = true;
      self.defaultStatus = Message;
   }
   else setTimeout("Download()", 100); // CHECKS DOWNLOAD STATUS EVERY 100 MS
   return true;
}

function CacheNextSlide() {
   if ((NextSlide < Slides.length) && (typeof Slides[NextSlide] == 'string'))
{ // ONLY CACHES THE IMAGES ONCE
      SlideReady = false;
      self.defaultStatus = 'Downloading next picture...';
      Slides[NextSlide] = CacheImage(Slides[NextSlide]);
      Download();
   }
   return true;
}

function StartSlideShow() {
   CurrentSlide = -1;
   Slides[0] = CacheImage(Slides[0]);
   SlideReady = true;
   ShowSlide(1);
}