// Functions to create and work the sub section drop down menus for the
// L2_starter template, and the L3 stock template.
// Updated 2005-01-20

// The number of miliseconds before the sub nav is hidden
var menuTimeOut = 1000;

// Is true if the browser supports the standard DOM
var dom = document.getElementById;

// Will contain an array of sub menu IDs
var menu = new Array();

// Index value when the menu variable gets filled initially
var menuIndice = 0;

// Sentinal variable to determine if the mouse is over the sub menu
var onMenu = false;

// Holds a reference to a sub menu so the sub menu helper function that
// hides the sub menu can access that object.
var globalobj;

// Sentinal variable to determine whether the user agent accessing this
// page is using a computer monitor (screen). This is a crude method for
// determining the CSS media type and is only set to true when an alternate
// style sheet of a certain media is activated.
var mediaScreen = false;

function initializeMenu() {
  if (dom) {
    // Activate the style sheet to format the DHTML menu
    activateStyleSheet("DHTMLmenu");
    
    // Variables to hold references to a DOM node
    var LInode, DIVnode, ULnode, navRoot = document.getElementById("navRoot");
    // Loop variables
    var i=0,j=0,k=0;
    
    // Parse the DOM to add menu IDs to a global array
    for (i=0; i < navRoot.childNodes.length; i++) {
      LInode = navRoot.childNodes[i];
      if (LInode.nodeName == "LI" && LInode.className == "hasSubs") {
        correctIELayering(LInode, 900 - menuIndice);
        for (j=0; j < LInode.childNodes.length; j++) {
          DIVnode = LInode.childNodes[j];
          // The vertical menu, like that used in the L2_starter template
          // gets caught right here
          if (DIVnode.nodeName == "UL" && DIVnode.className == "subs") {
            menu[menuIndice] = DIVnode.getAttribute("id");
            menuIndice++;
          }
          // The horizontal menu, like that in template L3 has an extra DIV
          // tag used to fix a positioning bug in Safari 1.0.x that encases
          // the UL tag that contains the sub menu.
          else if (DIVnode.nodeName == "DIV" && DIVnode.className == "fixSafari") {
            correctIELayering(DIVnode, 900 - menuIndice);
            for (k=0; k < DIVnode.childNodes.length; k++) {
              ULnode = DIVnode.childNodes[k];
              if (ULnode.nodeName == "UL" && ULnode.className == "subs") {
                menu[menuIndice] = ULnode.getAttribute("id");
                menuIndice++;
              }
            }
          }
        }
      }
    }
  }
}

function showMenu(obj) {
  if (dom) {
    var topLevelSection;
    onMenu = true;
    
    // Hide all sub menus, regardless of which one has been moused over
    for (var i = 0; i < menu.length; i++) {
      document.getElementById(menu[i]).style.visibility = "hidden";
    }
    
    // Make the requested sub menu visible
    document.getElementById(obj).style.visibility = "visible";
    topLevelSection = document.getElementById(obj);
    topLevelSection = topLevelSection.parentNode;
    
    // Assign a class name to a top level section name (encased in a <span>
    // tag) so that the SPAN tag can be styled when the user mouses over a
    // sub menu item.
    for (var i = 0; i < topLevelSection.childNodes.length; i++) {
      if (topLevelSection.childNodes[i].nodeName == "SPAN") {
        topLevelSection.childNodes[i].className = "topLevelSection";
      }
    }
    onMenu = true;
  }
}

function hideMenu(obj) {
  globalobj = obj
  if (dom) {
    var topLevelSection;
    onMenu = false;
    
    // Wait before actually hiding the menu, in case the user moves over
    // another sub menu item.
    setTimeout("hideMenuHelper()",menuTimeOut);
    
    topLevelSection = document.getElementById(obj);
    topLevelSection = topLevelSection.parentNode;
    for (var i = 0; i < topLevelSection.childNodes.length; i++) {
      if (topLevelSection.childNodes[i].nodeName == "A" || topLevelSection.childNodes[i].nodeName == "SPAN") {
        topLevelSection.childNodes[i].className = "";
      }
    }
  }
}

function hideMenuHelper() {
  if (dom && onMenu == false && mediaScreen) {
    var obj = globalobj;
    document.getElementById(obj).style.visibility = "hidden";
  }
}

function keepMenu(obj) {
  onMenu = true;
  if (dom) {
  var topLevelSection = document.getElementById(obj);
    topLevelSection = topLevelSection.parentNode;
    for (var i = 0; i < topLevelSection.childNodes.length; i++) {
      if (topLevelSection.childNodes[i].nodeName == "A" || topLevelSection.childNodes[i].nodeName == "SPAN") {
        topLevelSection.childNodes[i].className = "topLevelSection";
      }
    }
  }
}

// Activate Alternate Style Sheet
// cssTitle: The value of the title attribute for the alternate style sheet
// you want to enable
function Original_activateStyleSheet(cssTitle) {
  if (dom) {
    var linkTags = document.getElementsByTagName("link");
    for (var i = 0; i < linkTags.length; i++) {
      if (linkTags[i].getAttribute("title") == cssTitle) {
        linkTags[i].disabled = true; // Required by Internet Explorer
        linkTags[i].disabled = false;
        mediaScreen = true;
      }
    }
  }
}

function activateStyleSheet(title) {
/*
  2011-08-10: This method was rewritten to provide a fix for Safari 5.1,
  because of a bug in this browser that does not process "a.disabled = false".
  Compare to the original version above.

  The trick: The code finds the following CSS stylesheet link:

    L2, L6: <link rel="stylesheet" type="text/css" media="handheld" href="/css/{$template}/{$skin}/handheld/basic.css" />
    L7, L8: <link rel="stylesheet" type="text/css" media="handheld" href="/css/{$template}/handheld/basic.css" />

  by searching all links for the only one that has "handheld" as the value for the "media" attribute. It then searches
  for the link with a "title" attribute matching the value passed in (in our case "DHTMLmenu"). It grabs the "href" for
  the DHTMLmenu link and overwrites the "href" for the handheld link (which IS NOT an alternate stylesheet) and finally
  changes the "media" attribute from "handheld" to "screen" - essentially swapping the alternate stylesheet with the
  handheld stylesheet.  Doing that fixes the broken fly-out menus in Safari v5.1.

  NOTE: Once Apple releases a patch to fix Safari, the original function above can be restored and this one deleted.
*/
  var a, link, href = '';
  for (var i = 0; (a = document.getElementsByTagName("link")[i]); i++) {
    // If this object is the link element that will hold the link to the enabled stylesheet, store the reference
    if (a.getAttribute("media") == "handheld") link = a;         
    if (a.getAttribute("rel").indexOf("style") != -1 && a.getAttribute("title")) {
      if (a.getAttribute("title") == title) {
        href = a.href;
        mediaScreen = true;
      }
    }
  }
  // Set href attribute of the link element
  link.setAttribute("href", href);
  link.setAttribute("media", 'screen');
}

// Internet Explorer doesn't layer relatively and absolutely positioned
// elements correctly. The top level section further down the menu
// (relatively positioned) would appear above a list of sub sections
// (absolutely positioned and given a higher z-index).
//
// ARGUMENTS:
// node   - A reference to the DOM node that needs the z-index adjusted
// zindex - The z-index to be given to node
function correctIELayering(node, zindex) {
  if (dom && document.all)
    node.style.zIndex = zindex;
}

// L6 - Submenu Nav Bar
// If submenu navigation <ul> is empty of elements (nodeType = 1)
// don't display an empty submenu - remove the container <div>
// by setting it's "display" style to "none".
//
// Look for "elements" specifically (nodeType = 1), because there 
// could be HTML comments (nodeType = 8) in the <ul>, but it would
// still render as nothing in the browser.
function toggleSubMenuNavBarDisplay(searchElement, hideElement, disableDropdowns) {

  if((searchElement == null || hideElement == null) && ! disableDropdowns) {
    initializeMenu();
    return;
  }

  var ul = document.getElementById(searchElement);
  var flag = false;

  if (ul == null) {
    flag = true;
  } else {
    if (ul.hasChildNodes()) {
      flag = true;
      for (i=0; i<ul.childNodes.length; i++) {
        if (ul.childNodes[i].nodeType == "1") {
          flag = false;
          break;
        }
      }
    } else {
      flag = true;
    }
  }
  if (flag) {
    document.getElementById(hideElement).style.display = "none";
  } else {
    if (searchElement == "navRoot" && ! disableDropdowns) initializeMenu();
  }
}