/* menuDropdown.js - implements a dropdown menu based on a HTML list                  
 * Author: Dave Lindquist (http://www.gazingus.org)                                   
 * Modified by: Nicolas Lesbats (nicolas lesbats at laposte net)                      
 * Version: 0.1b (2004-03-11)                                                         
 */                                                                                   
                                                                                      
var maxWidth = 50;                                                                    
/* maximum width of the submenus (in 'em' units) */                                   
                                                                                      
var borderBox  = false;                                                               
var horizontal = new Array();                                                         
var menuTop    = new Array();                                                         
var menuHeight = new Array();                                                         
var menuLeft   = new Array();                                                         
var menuWidth  = new Array();                                                         
                                                                                      
window.onload = function() { loadMenu(); }                                            
                                                                                      
function loadMenu() {                                                                 
  if (!document.getElementById) return;                                               
  var i = 0, j, root, submenus, node, li, link, division;                             
  while (true) {                                                                      
    root = document.getElementById("menuList" + (i + 1));                             
    if (root == null)                                                                 
      break;                                                                          
    submenus = root.getElementsByTagName("ul");                                       
    division = root.parentNode;                                                       
                                                                                      
    if (document.createElement) {                                                     
      /* Win/IE5-6 trick: makes the whole width of the submenus clickable             
       */                                                                             
      for (j = 0; j < submenus.length; j++) {                                         
        node = submenus.item(j);                                                      
        if (node.className == "menu" && node.getElementsByTagName("ul").length == 0) {
          li = document.createElement("li");                                          
          node.appendChild(li);                                                       
          li.style.position = "absolute";                                             
          li.style.visibility = "hidden";                                             
        }                                                                             
      }                                                                               
      /* checks whether the 'width' property applies to the border box or             
       * the content box of an element                                                
       */                                                                             
      if (i == 0) {                                                                   
        li.style.display = "block";                                                   
        li.style.padding = "0";                                                       
        li.style.width   = "2px";                                                     
        li.style.border  = "1px solid";                                               
        if (li.offsetWidth == 2)                                                      
          borderBox = true;                                                           
      }                                                                               
    }                                                                                 
                                                                                      
    initializeMenu(root, division, i);                                                
                                                                                      
    for (j = 0; j < submenus.length; j++) {                                           
      node = submenus.item(j);                                                        
      if (node.className == "menu") {                                                 
        link = node.previousSibling;                                                  
        while (link != null) {                                                        
          if (link.className == "actuator" || link.className == "actuator_selected") {                                         
            initializeSubmenu(node, link, root, division);                            
            node.set();                                                               
            break;                                                                    
          }                                                                           
          link = link.previousSibling;                                                
        }                                                                             
      }                                                                               
    }                                                                                 
    i++;                                                                              
  }                                                                                   
}                                                                                     
                                                                                      
function initializeMenu(root, div, index) {                                           
                                                                                      
  horizontal[index] = menuIsHorizontal(root);                                         
  menuTop[index]    = div.offsetTop;                                                  
  menuHeight[index] = div.offsetHeight;                                               
  menuLeft[index]   = div.offsetLeft;                                                 
  menuWidth[index]  = div.offsetWidth;                                                
                                                                                      
  div.horizontal = function() {                                                       
    return horizontal[index];                                                         
  }                                                                                   
                                                                                      
  div.checkMove = function() {                                                        
    if (this.hasMoved()) this.resetMenu();                                            
  }                                                                                   
                                                                                      
  div.hasMoved = function() {                                                         
    if (menuTop[index]    == this.offsetTop    &&                                     
        menuHeight[index] == this.offsetHeight &&                                     
        menuLeft[index]   == this.offsetLeft   &&                                     
        menuWidth[index]  == this.offsetWidth)                                        
      return false;                                                                   
    return true;                                                                      
  }                                                                                   
                                                                                      
  div.resetMenu = function() {                                                        
    horizontal[index] = menuIsHorizontal(root);                                       
    menuTop[index]    = this.offsetTop;                                               
    menuHeight[index] = this.offsetHeight;                                            
    menuLeft[index]   = this.offsetLeft;                                              
    menuWidth[index]  = this.offsetWidth;                                             
                                                                                      
    var submenus = root.getElementsByTagName("ul");                                   
    for (var j = 0; j < submenus.length; j++) {                                       
      var node = submenus.item(j);                                                    
      if (node.className == "menu") {                                                 
        node.style.right = "";                                                        
        node.style.left  = "";                                                        
        if (!window.opera)                                                            
          node.style.width = "";                                                      
        node.set();                                                                   
      }                                                                               
    }                                                                                 
  }                                                                                   
}                                                                                     
                                                                                      
function menuIsHorizontal(root) {                                                     
  var first = firstElement(root, "LI");                                               
  if (first != null) {                                                                
    var second = first.nextSibling;                                                   
    while (second != null) {                                                          
      if (second.tagName == "LI") {                                                   
        first  = firstElement(first,  "A");                                           
        second = firstElement(second, "A");                                           
        if (first != null && second != null)                                          
          if (first.offsetLeft == second.offsetLeft)                                  
            return false;                                                             
        return true;                                                                  
      }                                                                               
      second = second.nextSibling;                                                    
    }                                                                                 
  }                                                                                   
  return true;                                                                        
}                                                                                     
                                                                                      
function initializeSubmenu(menu, actuator, root, div) {                               
                                                                                      
  var parent = menu.parentNode;                                                       
                                                                                      
  parent.onmouseover = function() {                                                   
    div.checkMove();                                                                  
    menu.style.visibility = "visible";                                                
  }                                                                                   
                                                                                      
  actuator.onfocus = function() {                                                     
    div.checkMove();                                                                  
    menu.style.visibility = "visible";                                                
  }                                                                                   
                                                                                      
  parent.onmouseout = function() {                                                    
    menu.style.visibility = "";                                                       
  }                                                                                   
                                                                                      
  var tags = menu.getElementsByTagName("a");                                          
  var link = tags.item(tags.length - 1);                                              
  if (!link.onblur)                                                                   
    link.onblur = function() {                                                        
      var node = link.parentNode.parentNode;                                          
      while (node != menu) {                                                          
        node.style.visibility = "";                                                   
        node = node.parentNode.parentNode;                                            
      }                                                                               
      menu.style.visibility = "";                                                     
    }                                                                                 
                                                                                      
  if (parent.parentNode == root) {                                                    
    menu.set = function() {                                                           
      setLocation1(this, actuator, root, div);                                        
    }                                                                                 
  } else {                                                                            
    menu.set = function() {                                                           
      setLocation2(this, actuator, div);                                              
    }                                                                                 
  }                                                                                   
}                                                                                     
                                                                                      
function setLocation1(menu, actuator, root, div) {                                    
  var first = firstElement(menu, "LI");                                               
  if (first != null)                                                                  
    if (first.offsetParent == menu)                                                   
      setWidth(menu);                                                                 
  if (div.horizontal()) {                                                             
    if (actuator.offsetParent == menu.offsetParent) {                                 
      menu.style.left = actuator.offsetLeft + "px";                                   
      menu.style.top  = actuator.offsetTop  + actuator.offsetHeight + "px";           
    } else {                                                                          
      /* happens in Win/IE5-6 when some ancestors are 'static' and have their         
       * 'width' or 'height' different than 'auto' */                                 
      var parent = actuator.offsetParent;                                             
      var top  = 0;                                                                   
      var left = 0;                                                                   
      while (parent != menu.offsetParent && parent != null) {                         
        top  = top  + parent.offsetTop;                                               
        left = left + parent.offsetLeft;                                              
        parent = parent.offsetParent;                                                 
      }                                                                               
      menu.style.left = left + actuator.offsetLeft + "px";                            
      menu.style.top  = top  + actuator.offsetTop  + actuator.offsetHeight + "px";    
    }                                                                                 
  } else {                                                                            
    menu.style.top = actuator.offsetTop + "px";                                       
    menu.style.left = (div.offsetWidth + actuator.offsetWidth) / 2 + "px";            
  }                                                                                   
}                                                                                     
                                                                                      
function setLocation2(menu, actuator, div) {                                          
  if (menu.offsetParent != document.body)                                             
    setWidth(menu);                                                                   
  menu.style.top = actuator.offsetTop + "px";                                         
  menu.style.left = actuator.offsetWidth + "px";                                      
}                                                                                     
                                                                                      
function setWidth(menu) {                                                             
  menu.style.right = - maxWidth + "em";                                               
  var width  = 0;                                                                     
  var height = 0;                                                                     
  var items = menu.getElementsByTagName("a");                                         
  for (var i = 0; i < items.length; i++) {                                            
    var link = items.item(i);                                                         
    if (link.parentNode.parentNode == menu) {                                         
      height = height + link.offsetHeight;                                            
      if (link.offsetWidth > width)                                                   
        width = link.offsetWidth;                                                     
    }                                                                                 
  }                                                                                   
  if (borderBox)                                                                      
    width = width + (menu.offsetHeight - height);                                     
  menu.style.width = width + "px";                                                    
}                                                                                     
                                                                                      
function firstElement(node, name) {                                                   
  var first = node.firstChild;                                                        
  while (first != null) {                                                             
    if (first.tagName == name)                                                        
      return first;                                                                   
    first = first.nextSibling;                                                        
  }                                                                                   
  return null;                                                                        
}