function MenuLeft(id) {
  if (!document.getElementById || !document.getElementsByTagName) {
    return false;
  }
  this.menu = document.getElementById(id);
  this.submenus = this.menu.getElementsByTagName("div");
  this.remember = true;
  this.speed = 3;
  this.markCurrent = true;
  this.oneSmOnly = true;
}
MenuLeft.prototype.init = function () {
  var mainInstance = this;
  for (var i = 0; i < this.submenus.length; i++)
    this.submenus[i].getElementsByTagName("span")[0].onclick = function () {
      mainInstance.toggleMenu(this.parentNode);
    };
  if (this.markCurrent) {
    var links = this.menu.getElementsByTagName("a");
    for (var i = 0; i < links.length; i++)
      if (links[i].href == document.location.href) {
        links[i].className = "current";
        break;
      }
  }
  if (this.remember) {
    var regex = new RegExp("menu_left_" + encodeURIComponent(this.menu.id) + "=([01]+)");
    var match = regex.exec(document.cookie);
    if (match == null) {
      var states = new Array();
      for (var i = 0; i < this.submenus.length; i++)
        this.submenus[i].className = "collapsed";
      var d = new Date();
      d.setTime(d.getTime() + (30 * 24 * 60 * 60 * 1000));
      document.cookie = "menu_left_" + encodeURIComponent(this.menu.id) + "=" + states.join("") + "; expires=" + d.toGMTString() + "; path=/";
      mainInstance.memorize();
    }
    if (match) {
      var states = match[1].split("");
      for (var i = 0; i < states.length; i++) {
        this.submenus[i].className = (states[i] == 0 ? "collapsed" : "");
      }
    }
  }
};
MenuLeft.prototype.toggleMenu = function (submenu) {
  if (submenu.className == "collapsed") {
    this.expandMenu(submenu);
  }
  else {
    this.collapseMenu(submenu);
  }
};
MenuLeft.prototype.expandMenu = function (submenu) {
  var fullHeight = submenu.getElementsByTagName("span")[0].offsetHeight;
  var links = submenu.getElementsByTagName("a");
  for (var i = 0; i < links.length; i++)
    fullHeight += links[i].offsetHeight;
  var moveBy = Math.round(this.speed * links.length);

  var mainInstance = this;
  var intId = setInterval(function () {
    var curHeight = submenu.offsetHeight;
    var newHeight = curHeight + moveBy;
    if (newHeight < fullHeight)
      submenu.style.height = newHeight + "px";
    else {
      clearInterval(intId);
      submenu.style.height = "";
      submenu.className = "";
      mainInstance.memorize();
    }
  }, 30);
  this.collapseOthers(submenu);
};
MenuLeft.prototype.collapseMenu = function (submenu) {
  var minHeight = submenu.getElementsByTagName("span")[0].offsetHeight;
  var moveBy = Math.round(this.speed * submenu.getElementsByTagName("a").length);
  var mainInstance = this;
  var intId = setInterval(function () {
    var curHeight = submenu.offsetHeight;
    var newHeight = curHeight - moveBy;
    if (newHeight > minHeight)
      submenu.style.height = newHeight + "px";
    else {
      clearInterval(intId);
      submenu.style.height = "";
      submenu.className = "collapsed";
      mainInstance.memorize();
    }
  }, 30);
};
MenuLeft.prototype.collapseOthers = function (submenu) {
  if (this.oneSmOnly) {
    for (var i = 0; i < this.submenus.length; i++)
      if (this.submenus[i] != submenu && this.submenus[i].className != "collapsed")
        this.collapseMenu(this.submenus[i]);
  }
};
MenuLeft.prototype.expandAll = function () {
  var oldOneSmOnly = this.oneSmOnly;
  this.oneSmOnly = false;
  for (var i = 0; i < this.submenus.length; i++)
    if (this.submenus[i].className == "collapsed")
      this.expandMenu(this.submenus[i]);
  this.oneSmOnly = oldOneSmOnly;
};
MenuLeft.prototype.collapseAll = function () {
  for (var i = 0; i < this.submenus.length; i++)
    if (this.submenus[i].className != "collapsed")
      this.collapseMenu(this.submenus[i]);
};
MenuLeft.prototype.memorize = function () {
  if (this.remember) {
    var states = new Array();
    for (var i = 0; i < this.submenus.length; i++)
      states.push(this.submenus[i].className == "collapsed" ? 0 : 1);
    var d = new Date();
    d.setTime(d.getTime() + (30 * 24 * 60 * 60 * 1000));
    document.cookie = "menu_left_" + encodeURIComponent(this.menu.id) + "=" + states.join("") + "; expires=" + d.toGMTString() + "; path=/";
  }
};