var interval = 6000;
var random_display = 0;
var imageDir = "images/hilites/";
var waitflag = true;

var imageNum = 0;
imageArray = new Array();
imageArray[imageNum++] = new imageItem(imageDir + "cards.png", "/node/8");
imageArray[imageNum++] = new imageItem(imageDir + "specialty.png", "/node/15");
imageArray[imageNum++] = new imageItem(imageDir + "books.png", "/node/11");

var totalImages = imageArray.length;

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);
    } else {
      waitflag=false;
    }
  }
}

function imageItem(image_location, imgUrl) {
  this.image_item = new Image();
  this.image_item.src = image_location;
  this.image_url = imgUrl;
}

function get_ImageItemLocation(imageObj) {
  return(imageObj.image_item.src)
}

function randNum(x, y) {
  var range = y - x + 1;
  return Math.floor(Math.random() * range) + x;
}

function getNextImage() {
  if (random_display) {
    imageNum = randNum(0, totalImages-1);
  } else {
    imageNum = (imageNum+1) % totalImages;
  }
  var new_image = get_ImageItemLocation(imageArray[imageNum]);
  return(new_image);
}

function getPrevImage() {
  imageNum = (imageNum-1) % totalImages;
  var new_image = get_ImageItemLocation(imageArray[imageNum]);
  return(new_image);
}

function prevImage(place) {
  var new_image = getPrevImage();
  document[place].src = new_image;
}

function switchImage(place) {
  var new_image = getNextImage();

  var doit = "fadeOut('"+place+"', 100)";
  setTimeout(doit, 5000);

  document[place].src = new_image;
  pr=document[place].parentNode;
  pr.href = imageArray[imageNum].image_url;

  fadeIn(place, 0);

  var recur_call = "switchImage('"+place+"')";
  timerID = setTimeout(recur_call, interval);
}