var isIE5 = (navigator.userAgent.indexOf("MSIE 5.5") > 0  |
             navigator.userAgent.indexOf("MSIE 6.0") > 0) ? 1 : 0;
var isNS6 = (navigator.userAgent.indexOf("Gecko")    > 0) ? 1 : 0;
if (isIE5) {
  document.styleSheets[document.styleSheets.length - 1].addRule("#menuBar", "padding-top:4px");
  document.styleSheets[document.styleSheets.length - 1].addRule("#menuBar", "padding-bottom:3px");
}
var activeButton = null;
if (isIE5)
  document.onmousedown = pageMousedown;
if (isNS6)
  document.addEventListener("mousedown", pageMousedown, true);

function pageMousedown(event) {

  var className;
  if (isIE5)
    className = window.event.srcElement.className;
  if (isNS6)
    className = (event.target.className ?
      event.target.className : event.target.parentNode.className);

  if (className != "menuButton"  && className != "menuItem" &&
      className != "menuItemSep" && activeButton)
    resetButton(activeButton);
}

function buttonClick(button, menuName) {
  button.blur();
  if (!button.menu)
    button.menu = document.getElementById(menuName);
  if (activeButton && activeButton != button)
    resetButton(activeButton);
  if (button.isDepressed)
    resetButton(button);
  else
    depressButton(button);

  return false;
}
function buttonMouseover(button, menuName) {
  if (activeButton && activeButton != button) {
    resetButton(activeButton);
    if (menuName)
      buttonClick(button, menuName);
  }
}
function depressButton(button) {
  button.className = "menuButtonActive";
  if (isIE5 && !button.menu.firstChild.style.width)
    button.menu.firstChild.style.width =
      button.menu.offsetWidth + "px";
  x = getPageOffsetLeft(button);
  y = getPageOffsetTop(button) + button.offsetHeight;
  if (isIE5)
    y += 2;
  if (isNS6) {
    x--;
    y--;
  }
  button.menu.style.left = x + "px";
  button.menu.style.top  = y + "px";
  button.menu.style.visibility = "visible";
  button.isDepressed = true;
  activeButton = button;
}
function resetButton(button) {
  button.className = "menuButton";
  if (button.menu)
    button.menu.style.visibility = "hidden";
  button.isDepressed = false;
  activeButton = null;
}
function getPageOffsetLeft(el) {
  return el.offsetLeft + (el.offsetParent ? getPageOffsetLeft(el.offsetParent) : 0);
}
function getPageOffsetTop(el) {
  return el.offsetTop + (el.offsetParent ? getPageOffsetTop(el.offsetParent) : 0);
}