// Original:  Angus Turnbull
// Web Site:  http://gusnz.cjb.net

// This script and many more are available free online at
// The JavaScript Source!! http://javascript.internet.com
// Changes
// 20030206 Jeff Best 
// Added popSelect for navigation to ensure that a mouseUp
// in the white-space after a menu item's text was not ignored.
// 20040110 Jeff Best
// Shrunk menu number variable and added menu item variable to
// allow menus to be rearranged by direct dragging and dropping
// of menu and menu item lines.
//

var isDOM = (document.getElementById ? true : false); 
var isIE4 = ((document.all && !isDOM) ? true : false);
var isNS4 = (document.layers ? true : false);

function getRef(id) {
  if (isDOM) return document.getElementById(id);
  if (isIE4) return document.all[id];
  if (isNS4) return document.layers[id];
}

function getSty(id) {
  return (isNS4 ? getRef(id) : getRef(id).style);
} 

// Hide timeout.
var popTimer = 0;

// Array showing highlighted menu items.
var litNow = new Array();

function popSelect(target, url) {
  if ( url && url != "#" ) window.open(url, target)
}

function popOver(menuNum, itemNum) {
  clearTimeout(popTimer);
  hideAllBut(menuNum);
  litNow = getTree(menuNum, itemNum);
  changeCol(litNow, true);
  targetNum = menu[menuNum][itemNum].target;
  if (targetNum > 0) {
    thisX = parseInt(menu[menuNum][0].ref.left) + parseInt(menu[menuNum][itemNum].ref.left);
    thisY = parseInt(menu[menuNum][0].ref.top) + parseInt(menu[menuNum][itemNum].ref.top);
    with (menu[targetNum][0].ref) {
      left = parseInt(thisX + menu[targetNum][0].x);
      top = parseInt(thisY + menu[targetNum][0].y);
      visibility = 'visible';
    }
  }
}

function popOut(menuNum, itemNum) {
  if ((menuNum == 0) && !menu[menuNum][itemNum].target)
    hideAllBut(0)
  else
    popTimer = setTimeout('hideAllBut(0)', 500);

}

function getTree(menuNum, itemNum) {

  // Array index is the menu number. The contents are null (if that menu is not a parent)
  // or the item number in that menu that is an ancestor (to light it up).
  itemArray = new Array(menu.length);

  while(1) {
    itemArray[menuNum] = itemNum;
    // If we've reached the top of the hierarchy, return.
    if (menuNum == 0) return itemArray;
      itemNum = menu[menuNum][0].parentItem;
    menuNum = menu[menuNum][0].parentMenu;
  }
}

// Pass an array and a boolean to specify colour change, true = over colour.
function changeCol(changeArray, isOver) {
  for (menuCount = 0; menuCount < changeArray.length; menuCount++) {
    if (changeArray[menuCount]) {
      newCol = isOver ? menu[menuCount][0].overCol : menu[menuCount][0].backCol;
      // Change the colours of the div/layer background.
      with (menu[menuCount][changeArray[menuCount]].ref) {
        if (isNS4) bgColor = newCol;
        else backgroundColor = newCol;
      }
    }
  }
}

function hideAllBut(menuNum) {
  var keepMenus = getTree(menuNum, 1);
  for (count = 0; count < menu.length; count++)
    if (!keepMenus[count])
      menu[count][0].ref.visibility = 'hidden';
  changeCol(litNow, false);
}

// *** MENU CONSTRUCTION FUNCTIONS ***

function Menu(isVert, popInd, x, y, width, overCol, backCol, borderClass, textClass) {
  // True or false - a vertical menu?
  this.isVert = isVert;
  // The popout indicator used (if any) for this menu.
  this.popInd = popInd
  // Position and size settings.
  this.x = x;
  this.y = y;
  this.width = width;
  // Colours of menu and items.
  this.overCol = overCol;
  this.backCol = backCol;
  // The stylesheet class used for item borders and the text within items.
  this.borderClass = borderClass;
  this.textClass = textClass;
  // Parent menu and item numbers, indexed later.
  this.parentMenu = null;
  this.parentItem = null;
  // Reference to the object's style properties (set later).
  this.ref = null;
}

function Item(text, href, frame, length, spacing, target) {
  this.text = text;
  this.href = href;
  this.frame = frame;
  this.length = length;
  this.spacing = spacing;
  this.target = target;
  // Reference to the object's style properties (set later).
  this.ref = null;
}

function writeMenus() {
  if (!isDOM && !isIE4 && !isNS4) return;

  for (currMenu = 0; currMenu < menu.length; currMenu++) with (menu[currMenu][0]) {
    // Variable for holding HTML for items and positions of next item.
    var str = '', itemX = 0, itemY = 0;

    // Remember, items start from 1 in the array (0 is menu object itself, above).
    // Also use properties of each item nested in the other with() for construction.
    for (currItem = 1; currItem < menu[currMenu].length; currItem++) 
    with (menu[currMenu][currItem]) {
      var itemID = 'menu' + currMenu + 'item' + currItem;

      // The width and height of the menu item - dependent on orientation!
      var w = (isVert ? width : length);
      var h = (isVert ? length : width);

      // Create a div or layer text string with appropriate styles/properties.
      // Thanks to Paul Maden (www.paulmaden.com) for helping debug this in IE4, apparently
      // the width must be a miniumum of 3 for it to work in that browser.
      if (isDOM || isIE4) {
        str += '<div id="' + itemID + '" style="position: absolute; left: ' + itemX + '; top: ' +
               itemY + '; width: ' + w + '; height: ' + h + '; visibility: inherit; ';
        if (backCol) str += 'background: ' + backCol + '; ';
          str += '" ';
      }
      if (isNS4) {
        str += '<layer id="' + itemID + '" left="' + itemX + '" top="' + itemY + '" width="' +  w + 
               '" height="' + h + '" visibility="inherit" ';
        if (backCol) str += 'bgcolor="' + backCol + '" ';
      }
      if (borderClass) str += 'class="' + borderClass + '" ';

      // Add mouseover handlers and finish div/layer.
      str += 'onMouseOver="popOver(' + currMenu + ',' + currItem + ')" '
      str += 'onMouseOut="popOut(' + currMenu + ',' + currItem + ')" '
      str += 'onMouseUp="popSelect(' + "'" + frame + "'" + ',' + "'" + href + "'" + ')">';

      // Add contents of item (default: table with link inside).
      // In IE/NS6+, add padding if there's a border to emulate NS4's layer padding.
      // If a target frame is specified, also add that to the <a> tag.

      str += '<table width="' + (w - 8) + '" border="0" cellspacing="0" cellpadding="' + (!isNS4 &&       
             borderClass ? 3 : 0) + '"><tr><td align="left" height="' + (h - 7) + '">' + '<a class="' + 
             textClass + '" href="' + href + '"' + (frame ? ' target="' + frame + '">' : '>') + text + '</a></td>';
      if (target > 0) {

        // Set target's parents to this menu item.
        menu[target][0].parentMenu = currMenu;
        menu[target][0].parentItem = currItem;

        // Add a popout indicator.
        if (popInd) str += '<td class="' + textClass + '" align="right">' + popInd + '</td>';
      }
      str += '</tr></table>' + (isNS4 ? '</layer>' : '</div>');
      if (isVert) itemY += length + spacing;
      else itemX += length + spacing;
    }
    if (isDOM) {
      var newDiv = document.createElement('div');
      document.getElementsByTagName('body').item(0).appendChild(newDiv);
      newDiv.innerHTML = str;
      ref = newDiv.style;
      ref.position = 'absolute';
      ref.visibility = 'hidden';
    }

    // Insert a div tag to the end of the BODY with menu HTML in place for IE4.
    if (isIE4) {
      document.body.insertAdjacentHTML('beforeEnd', '<div id="menu' + currMenu + 'div" ' + 'style="position: absolute; visibility: hidden">' + str + '</div>');
      ref = getSty('menu' + currMenu + 'div');
    }

    // In NS4, create a reference to a new layer and write the items to it.
    if (isNS4) {
      ref = new Layer(0);
      ref.document.write(str);
      ref.document.close();
    }

    for (currItem = 1; currItem < menu[currMenu].length; currItem++) {
      itemName = 'menu' + currMenu + 'item' + currItem;
      if (isDOM || isIE4) menu[currMenu][currItem].ref = getSty(itemName);
      if (isNS4) menu[currMenu][currItem].ref = ref.document[itemName];
    }
  }

  with(menu[0][0]) {
    ref.left = x;
    ref.top = y;
    ref.visibility = 'visible';
  }
}

// Syntaxes: *** START EDITING HERE, READ THIS SECTION CAREFULLY! ***
//
// menu[menuNumber][0] = new Menu(Vertical menu? (true/false), 'popout indicator', left, top,
// width, 'mouseover colour', 'background colour', 'border stylesheet', 'text stylesheet');
//
// Left and Top are measured on-the-fly relative to the top-left corner of its trigger, or
// for the root menu, the top-left corner of the page.
//
// menu[menuNumber][itemNumber] = new Item('Text', 'URL', 'target frame', length of menu item,
//  additional spacing to next menu item, number of target menu to popout);
//
// If no target menu (popout) is desired, set it to 0. Likewise, if your site does not use
// frames, pass an empty string as a frame target.
//
// Something that needs explaining - the Vertical Menu setup. You can see most menus below
// are 'true', that is they are vertical, except for the first root menu. The 'length' and
// 'width' of an item depends on its orientation -- length is how long the item runs for in
// the direction of the menu, and width is the lateral dimension of the menu. Just look at
// the examples and tweak the numbers, they'll make sense eventually :).

var menu = new Array();

// Default colours passed to most menu constructors (just passed to functions, not
// a global variable - makes things easier to change later in bulk).
var defOver = '#336699', defBack = '#003366';

// Default 'length' of menu items - item height if menu is vertical, width if horizontal.
var defLength = 22;

// We use variables for the meu number (iMN) and menu item (iMI).
// This makes rearranging menus and menu items relatively straight-forward.
// The names are short to avoid making the item lines too long.
var iMN= 0
var iMI= 0

// Menu 0 is the special, 'root' menu from which everything else arises.
menu[iMN] = new Array();

// A non-vertical menu with a few different colours and no popout indicator, as an example.
// *** MOVE ROOT MENU AROUND HERE ***  it's positioned at (5, 0) and is 17px high now.
menu[iMN][iMI++] = new Menu(false, '', 5, 0, 17, '#C0C0C0', '#0C0C0C', '', 'itemText');

// Notice how the targets are all set to nonzero values...
// The 'length' of each of these items is 70, and there is spacing of 1 to the next item.
// Most of the links are set to '#' hashes, make sure you change them to actual files.

menu[iMN][iMI++] = new Item('  Poplog Sites',   '#', '', 100, 0, 1);
menu[iMN][iMI++] = new Item('  Languages',      '#', '', 100, 0, 2);
menu[iMN][iMI++] = new Item('  Libraries',      '#', '', 100, 0, 3);
menu[iMN][iMI++] = new Item('  Contributions',  '#', '', 120, 0, 4);
menu[iMN][iMI++] = new Item('  Contributors',   '#', '', 120, 0, 5);
menu[iMN][iMI++] = new Item('  Documentation',  '#', '', 120, 0, 6); // 7-8 are doc, teach sub-menus
menu[iMN][iMI++] = new Item('  Development',    '#', '', 120, 0, 9);
menu[iMN][iMI++] = new Item('  Help',           '#', '', 100, 0, 10);

// Poplog menu
iMN++
iMI = 0
menu[iMN] = new Array();
menu[iMN][iMI++] = new Menu(true, '>', 0, 22, 240, defOver, defBack, 'itemBorder', 'itemText');
menu[iMN][iMI++] = new Item('poplog.org',               'http://www.poplog.org', '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('OpenPoplog on SourceForge','http://www.sourceforge.net/projects/openpoplog', '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('University of Birmingham', 'http://www.cs.bham.ac.uk/research/poplog/freepoplog.html', '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Sussex University',        'http://www.cogs.susx.ac.uk/users/adrianh/poplog.html', '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Reading University',       'http://www.cvg.cs.reading.ac.uk/poplog', '_top', defLength, 0, 0);

// Languages menu
iMN++
iMI = 0
menu[iMN] = new Array();
menu[iMN][iMI++] = new Menu(true, '>', 0, 22, 160, defOver, defBack, 'itemBorder', 'itemText');
menu[iMN][iMI++] = new Item('Common Lisp',   'http://www.cs.bham.ac.uk/research/poplog/doc/lisphelp/clisp',   '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('ML',            'http://www.cs.bham.ac.uk/research/poplog/doc/pmlhelp/',         '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Pop-11',        'http://www.cs.bham.ac.uk/research/poplog/primer/',              '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Prolog (PDF)',  'http://www.cf.ac.uk/infos/guides/unix/unx016.pdf',              '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Sys-Pop-11',    '#', '', defLength, 0, 0);


// Libraries menu
iMN++
iMI = 0
menu[iMN] = new Array();
menu[iMN][iMI++] = new Menu(true, '>', 0, 22, 160, defOver, defBack, 'itemBorder', 'itemText');
menu[iMN][iMI++] = new Item('Database',       '#',   '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Flavours',       'http://openpoplog.sourceforge.net/ref/flavours.html',                   '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('lr_parser',      '#',   '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('ObjectClass',    'http://www.cs.bham.ac.uk/research/poplog/objectclass/help/objectclass', '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('RC Graphics',    'http://www.cs.bham.ac.uk/research/poplog/freepoplog.html#rclibfiles',   '_top', defLength, 0, 0);

// Contributions menu.
iMN++
iMI = 0
menu[iMN] = new Array();
menu[iMN][iMI++] = new Menu(true, '>', 0, 22, 160, defOver, defBack, 'itemBorder', 'itemText');
menu[iMN][iMI++] = new Item('Eliza',          'http://www.cs.bham.ac.uk/research/poplog/freepoplog.html#teacheliza', '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('GOSPL',          'http://www.poplog.org/gospl',                                         '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('NonLin',         'http://www.cs.bham.ac.uk/research/poplog/freepoplog.html#nonlin',     '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('ODBC for Poplog','http://www.poplog.org/workshop/odbc',                                 '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('PopVision',      'http://www.cogs.susx.ac.uk/users/davidy/teachvision/vision0.html',    '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('PopScheme',      'http://www.cs.bham.ac.uk/research/poplog/freepoplog.html#scheme',     '_top', defLength, 0, 0);
//menu[iMN][iMI++] = new Item('RBFS',          '#',                                                                  '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('SimAgent',       'http://www.cs.bham.ac.uk/~axs/cogaff/simagent.html',                  '_top', defLength, 0, 0);

// Contributors menu
iMN++
iMI = 0
menu[iMN] = new Array();
menu[iMN][iMI++] = new Menu(true, '>', 0, 22, 160, defOver, defBack, 'itemBorder', 'itemText');
menu[iMN][iMI++] = new Item('Credits',              'http://openpoplog.sourceforge.net/credits.html',  '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Rod Burstall',         'http://www.dcs.ed.ac.uk/home/rb/',                '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Chris Mellish',        'http://www.dai.ed.ac.uk/homes/chrism/',           '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Robin J. Popplestone (1938-2004)', 'http://www.inf.ed.ac.uk/events/robinp.html', '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Robert Rae',           'http://www.aiai.ed.ac.uk/~rhr/cv.html',           '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Allan Ramsay',         'http://www.co.umist.ac.uk/~allan/',               '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Aaron Sloman',         'http://www.cs.bham.ac.uk/~axs/',                  '_top', defLength, 0, 0);

// Documentation menu
iMN++
iMI = 0
menu[iMN] = new Array();
menu[iMN][iMI++] = new Menu(true, '>', 0, 22, 160, defOver, defBack, 'itemBorder', 'itemText');
menu[iMN][iMI++] = new Item('Pop-11 Primer',   'http://www.poplog.org/docs/primer',      '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Poplog Man Page', 'http://www.cs.bham.ac.uk/research/poplog/setup/man/man1/poplog.html',      '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('DOC',             '>',      '_top', defLength, 0, iMN + 1);
menu[iMN][iMI++] = new Item('HELP',            'http://openpoplog.sourceforge.net/help/index.html',     '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('REF',             'http://openpoplog.sourceforge.net/ref/index.html',      '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('TEACH',           '>',      '_top', defLength, 0, iMN + 2);
menu[iMN][iMI++] = new Item('NEWS',            'http://openpoplog.sourceforge.net/news.html',           '_top', defLength, 0, 0);

// DOC Menu
iMN++
iMI = 0
menu[iMN] = new Array();
menu[iMN][iMI++] = new Menu(true, '>', 20, 22, 120, defOver, defBack, 'itemBorder', 'itemText');
menu[iMN][iMI++] = new Item('Continuation',  'http://openpoplog.sourceforge.net/doc/continuation.html',      '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('DOC Files',     'http://openpoplog.sourceforge.net/doc/docfiles.html',          '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('HPPA',          'http://openpoplog.sourceforge.net/doc/hppa.html',              '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('M Code',        'http://openpoplog.sourceforge.net/doc/m_code.html',            '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Windows NT',    'http://openpoplog.sourceforge.net/doc/nt.html',                '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Porting Guide', 'http://openpoplog.sourceforge.net/doc/ppg.html',               '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('popc',          'http://openpoplog.sourceforge.net/doc/popc.html',              '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('syspop11',      'http://openpoplog.sourceforge.net/doc/syspop11.html',          '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('sysspec',       'http://openpoplog.sourceforge.net/doc/sysspec.html',           '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('VED Manual',    'http://openpoplog.sourceforge.net/doc/vedmanual.html',         '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('VED User Guide','http://openpoplog.sourceforge.net/doc/veduserguide.html',      '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('X Bibliography','http://openpoplog.sourceforge.net/doc/xbibliography.html',     '_top', defLength, 0, 0);

// TEACH Menu
iMN++
iMI = 0
menu[iMN] = new Array();
menu[iMN][iMI++] = new Menu(true, '>', 20, 22, 120, defOver, defBack, 'itemBorder', 'itemText');

// Development menu
iMN++
iMI = 0
menu[iMN] = new Array();
menu[iMN][iMI++] = new Menu(true, '>', 0, 22, 160, defOver, defBack, 'itemBorder', 'itemText');
menu[iMN][iMI++] = new Item('OpenPoplog and CVS',   'http://openpoplog.sourceforge.net/OpenPoplogCVS.html',          '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Building OpenPoplog',  'http://openpoplog.sourceforge.net/OpenPoplogBuild.html',        '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Installing OpenPoplog','http://openpoplog.sourceforge.net/OpenPoplogInstall.html',      '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Manifesto',            'http://openpoplog.sourceforge.net/manifesto.html',              '_top', defLength, 0, 0);


// Help menu
iMN++
iMI = 0
menu[iMN] = new Array();
// This menu needs to be a fraction wider because of "Poplog Evolution (PDF)"
menu[iMN][iMI++] = new Menu(true, '>', 0, 22, 170, defOver, defBack, 'itemBorder', 'itemText');
menu[iMN][iMI++] = new Item('About OpenPoplog',      'http://openpoplog.sourceforge.net/index.html',              '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('About Poplog',          'http://www.poplog.org/about',                               '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('SourceForge',           'http://www.sourceforge.net',                                '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Poplog Evolution (PDF)','http://www.cs.bham.ac.uk/research/cogaff/sloman.pop11.pdf', '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Copyright',             'http://openpoplog.sourceforge.net/copyright.html',          '_top', defLength, 0, 0);
menu[iMN][iMI++] = new Item('Credits',               'http://openpoplog.sourceforge.net/credits.html',            '_top', defLength, 0, 0);

// *** OPTIONAL CODE FROM HERE DOWN ***

// These two lines handle the window resize bug in NS4. See <body onResize="...">.
// I recommend you leave this here as otherwise when you resize NS4's width menus are hidden.

var popOldWidth = window.innerWidth;
nsResizeHandler = new Function('if (popOldWidth != window.innerWidth) location.reload()');


// This is a quick snippet that captures all clicks on the document and hides the menus
// every time you click. Use if you want.

if (isNS4) document.captureEvents(Event.CLICK);
document.onclick = clickHandle;

function clickHandle(evt)
{
 if (isNS4) document.routeEvent(evt);
 hideAllBut(0);
}


// This is just the moving command for the example.

function moveRoot()
{
 with(menu[0][0].ref) left = ((parseInt(left) < 100) ? 100 : 5);
}
//  End -->