var images = new Array (
  "images/image1.png",
  "images/image2.png",
  "images/image3.png",
  "images/image4.png",
  "images/image5.png",
  "images/image6.png"
);

var menus = new Array (
  "images/menu1.png",
  "images/menu2.png",
  "images/menu3.png",
  "images/menu4.png",
  "images/menu5.png",
  "images/menu6.png"
);

var menus_selected = new Array (
  "images/menu1_sel.png",
  "images/menu2_sel.png",
  "images/menu3_sel.png",
  "images/menu4_sel.png",
  "images/menu5_sel.png",
  "images/menu6_sel.png"
);

var menu_items = new Array (
  "item1",
  "item2",
  "item3",
  "item4",
  "item5",
  "item6"
);

var descriptions = new Array (
  "description1",
  "description2",
  "description3",
  "description4",
  "description5",
  "description6"
);

var lastSelectedIndex = 0;

function onLoad() {
  changeImage(0);
}

function changeImage(index) {

  document.images.screenshot.src = images[index];
  document.getElementById(menu_items[lastSelectedIndex]).src = menus[lastSelectedIndex];
  document.getElementById(menu_items[index]).src = menus_selected[index];
  lastSelectedIndex = index;
  
  var descriptionNode = document.getElementById("description");
  
  children = descriptionNode.childNodes;
  if(children != null) {
    for (var i = 0; i < children.length; i++)
      descriptionNode.removeChild(children[i]);
  }

  children = document.getElementById(descriptions[index]).childNodes;
  if(children != null) {
    for (var j = 0; j < children.length; j++) {
        nodeClone = children[j].cloneNode(true);
        descriptionNode.appendChild(nodeClone);
      }
    }
}