// Globals
var _cmIDCount = 0;
var _cmIDName = 'cmSubMenuID';        // for creating submenu id

var _cmTimeOut = null;            // how long the menu would stay
var _cmCurrentItem = null;        // the current menu item being selected;

var _command_no_action_ = new Object ();    // indicate that the item cannot be hovered.
var _cmSplit = new Object ();        // indicate that the item is a menu split

var _cmItemList = new Array ();        // a simple list of items

// default node properties
var _cmNodeProperties =
{
    // main menu display attributes
    //
    // Note.  When the menu bar is horizontal,
    // _folderLeft and _folderRight are
    // put in <span></span>.  When the menu
    // bar is vertical, they would be put in
    // a separate TD cell.

    // HTML code to the left of the folder item
    _folderLeft: '',
    // HTML code to the right of the folder item
    _folderRight: '',
    // HTML code to the left of the regular item
    _itemLeft: '',
    // HTML code to the right of the regular item
    _itemRight: '',

    // sub menu display attributes

    // HTML code to the left of the folder item
    folderLeft: '',
    // HTML code to the right of the folder item
    folderRight: '',
    // HTML code to the left of the regular item
    itemLeft: '',
    // HTML code to the right of the regular item
    itemRight: '',
    // cell spacing for main menu
    mainSpacing: 0,
    // cell spacing for sub menus
    subSpacing: 0,
    // auto dispear time for submenus in milli-seconds
    delay: 500
};

//////////////////////////////////////////////////////////////////////
//
// Drawing Functions and Utility Functions
//
//////////////////////////////////////////////////////////////////////

//
// produce a new unique id
//
function cmNewID ()
{
    return _cmIDName + (++_cmIDCount);
}

//
// return the property string for the menu item
//
function cmActionItem (item, prefix, isMain, idSub, orient, nodeProperties)
{
    // var index = _cmItemList.push (item) - 1;
    _cmItemList[_cmItemList.length] = item;
    var index = _cmItemList.length - 1;
    idSub = (!idSub) ? 'null' : ('\'' + idSub + '\'');
    orient = '\'' + orient + '\'';
    prefix = '\'' + prefix + '\'';
    return ' onmouseover="cmItemMouseOver (this,' + prefix + ',' + isMain + ',' + idSub + ',' + orient + ',' + index + ')" onmouseout="cmItemMouseOut (this,' + nodeProperties.delay + ')" onmousedown="cmItemMouseDown (this,' + index + ')" onmouseup="cmItemMouseUp (this,' + index + ')"';
}

function cmNoActionItem (item, prefix)
{
    return item[1];
}

function cmSplitItem (prefix, isMain, vertical)
{
    var classStr = 'cm' + prefix;
    if (isMain)
    {
        classStr += 'Main';
        if (vertical)
            classStr += 'HSplit';
        else
            classStr += 'VSplit';
    }
    else
        classStr += 'HSplit';
    var item = eval (classStr);
    return cmNoActionItem (item, prefix);
}

//
// draw the sub menu recursively
//
function cmDrawSubMenu (subMenu, prefix, id, orient, nodeProperties)
{
    var str = '<div class="' + prefix + 'SubMenu" id="' + id + '"><table summary="sub menu" cellspacing="' + nodeProperties.subSpacing + '" class="' + prefix + 'SubMenuTable">';
    var strSub = '';
    var item;
    var idSub;
    var hasChild;

    var i;

    var classStr;

    for (i = 5; i < subMenu.length; ++i)
    {
        item = subMenu[i];
        if (!item)
            continue;

        hasChild = (item.length > 5);
        idSub = hasChild ? cmNewID () : null;

        str += '<tr class="' + prefix + 'MenuItem"' + cmActionItem (item, prefix, 0, idSub, orient, nodeProperties) + '>';

        if (item == _cmSplit)
        {
            str += cmSplitItem (prefix, 0, true);
            str += '</tr>';
            continue;
        }

        if (item[0] == _command_no_action_)
        {
            str += cmNoActionItem (item, prefix);
            str += '</tr>';
            continue;
        }

        classStr = prefix + 'Menu';
        classStr += hasChild ? 'Folder' : 'Item';

        str += '<td nowrap class="' + classStr + 'Left">';

        if (item[0] != null && item[0] != _command_no_action_)
            str += item[0];
        else
            str += hasChild ? nodeProperties.folderLeft : nodeProperties.itemLeft;

        str += '<td nowrap class="' + classStr + 'Text">' + item[1];

        str += '<td nowrap class="' + classStr + 'Right">';

        if (hasChild)
        {
            str += nodeProperties.folderRight;
            strSub += cmDrawSubMenu (item, prefix, idSub, orient, nodeProperties);
        }
        else
            str += nodeProperties.itemRight;
        str += '</td></tr>';
    }

    str += '</table></div>' + strSub;
    return str;
}

//
// The function that builds the menu inside the specified element id.
//
// @param    id    id of the element
//        orient    orientation of the menu in [hv][ab][lr] format
//        menu    the menu object to be drawn
//        nodeProperties    properties for each menu node
//
function cmDraw (id, menu, orient, nodeProperties, prefix)
{
    var obj = cmGetObject (id);

    if (!nodeProperties)
        nodeProperties = _cmNodeProperties;
    if (!prefix)
        prefix = '';

    var str = '<table summary="main menu" class="' + prefix + 'Menu" cellspacing="' + nodeProperties.mainSpacing + '">';
    var strSub = '';

    if (!orient)
        orient = 'hbr';

    var orientStr = String (orient);
    var orientSub;
    var vertical;

    // draw the main menu items
    if (orientStr.charAt (0) == 'h')
    {
        // horizontal menu
        orientSub = 'v' + orientStr.substr (1, 2);
        str += '<tr>';
        vertical = false;
    }
    else
    {
        // vertical menu
        orientSub = 'v' + orientStr.substr (1, 2);
        vertical = true;
    }

    var i;
    var item;
    var idSub;
    var hasChild;

    var classStr;

    for (i = 0; i < menu.length; ++i)
    {
        item = menu[i];

        if (!item)
            continue;

        str += vertical ? '<tr' : '<td';
        str += ' class="' + prefix + 'MainItem"';

        hasChild = (item.length > 5);
        idSub = hasChild ? cmNewID () : null;

        str += cmActionItem (item, prefix, 1, idSub, orient, nodeProperties) + '>';

        if (item == _cmSplit)
        {
            str += cmSplitItem (prefix, 1, vertical);
            str += vertical? '</tr>' : '</td>';
            continue;
        }

        if (item[0] == _command_no_action_)
        {
            str += cmNoActionItem (item, prefix);
            str += vertical? '</tr>' : '</td>';
            continue;
        }

        classStr = prefix + 'Main' + (hasChild ? 'Folder' : 'Item');

        str += vertical ? '<td' : '<span';
        str += ' class="' + classStr + 'Left">';
       

        str += (item[0] == null) ? (hasChild ? nodeProperties._folderLeft : nodeProperties._itemLeft)
                     : item[0];
        str += vertical ? '</td>' : '</span>';

        str += vertical ? '<td' : '<span';
        str += ' class="' + classStr + 'Text">';
        str += item[1];

        str += vertical ? '</td>' : '</span>';

        str += vertical ? '<td' : '<span';
        str += ' class="' + classStr + 'Right">';

        str += hasChild ? nodeProperties._folderRight : nodeProperties._itemRight;

        str += vertical ? '</td>' : '</span>';

        str += vertical ? '</tr>' : '</td>';

        if (hasChild)
            strSub += cmDrawSubMenu (item, prefix, idSub, orientSub, nodeProperties);
    }
    if (!vertical)
        str += '</tr>';
    str += '</table>' + strSub;
    obj.innerHTML = str;
    //document.write ("<xmp>" + str + "</xmp>");
}

//////////////////////////////////////////////////////////////////////
//
// Mouse Event Handling Functions
//
//////////////////////////////////////////////////////////////////////

//
// action should be taken for mouse moving in to the menu item
//
function cmItemMouseOver (obj, prefix, isMain, idSub, orient, index)
{
    clearTimeout (_cmTimeOut);

    if (!obj.cmPrefix)
    {
        obj.cmPrefix = prefix;
        obj.cmIsMain = isMain;
    }

    var thisMenu = cmGetThisMenu (obj, prefix);

    // insert obj into cmItems if cmItems doesn't have obj
    if (!thisMenu.cmItems)
        thisMenu.cmItems = new Array ();
    var i;
    for (i = 0; i < thisMenu.cmItems.length; ++i)
    {
        if (thisMenu.cmItems[i] == obj)
            break;
    }
    if (i == thisMenu.cmItems.length)
    {
        //thisMenu.cmItems.push (obj);
        thisMenu.cmItems[i] = obj;
    }

    // hide the previous submenu that is not this branch
    if (_cmCurrentItem)
    {
        // occationally, we get this case when user
        // move the mouse slowly to the border
        if (_cmCurrentItem == thisMenu)
            return;

        var thatPrefix = _cmCurrentItem.cmPrefix;
        var thatMenu = cmGetThisMenu (_cmCurrentItem, thatPrefix);
        if (thatMenu != thisMenu.cmParentMenu)
        {
            if (_cmCurrentItem.cmIsMain)
                _cmCurrentItem.className = thatPrefix + 'MainItem';
            else
                _cmCurrentItem.className = thatPrefix + 'MenuItem';
            if (thatMenu.id != idSub)
                cmHideMenu (thatMenu, thisMenu, thatPrefix);
        }
    }

    // okay, set the current menu to this obj
    _cmCurrentItem = obj;

    // just in case, reset all items in this menu to MenuItem
    cmResetMenu (thisMenu, prefix);

    var item = _cmItemList[index];
    var isDefaultItem = cmIsDefaultItem (item);

    if (isDefaultItem)
    {
        if (isMain)
            obj.className = prefix + 'MainItemHover';
        else
            obj.className = prefix + 'MenuItemHover';
    }

    if (idSub)
    {
        var subMenu = cmGetObject(idSub);
        if (subMenu)
            cmShowSubMenu(obj, prefix, subMenu, orient);
    }

    var descript = '';
    if (item.length > 4)
        descript = (item[4] != null) ? item[4] : (item[2] ? item[2] : descript);
    else if (item.length > 2)
        descript = (item[2] ? item[2] : descript);

    window.defaultStatus = descript;
}

//
// action should be taken for mouse moving out of the menu item
//
function cmItemMouseOut (obj, delayTime)
{
    if (!delayTime)
        delayTime = _cmNodeProperties.delay;
    _cmTimeOut = window.setTimeout ('cmHideMenuTime ()', delayTime);
    window.defaultStatus = '';
}

//
// action should be taken for mouse button down at a menu item
//
function cmItemMouseDown (obj, index)
{
    if (cmIsDefaultItem (_cmItemList[index]))
    {
        if (obj.cmIsMain)
            obj.className = obj.cmPrefix + 'MainItemActive';
        else
            obj.className = obj.cmPrefix + 'MenuItemActive';
    }
}

//
// action should be taken for mouse button up at a menu item
//
function cmItemMouseUp (obj, index)
{
    var item = _cmItemList[index];

    var link = null, target = '_self';

    if (item.length > 2)
        link = item[2];
    if (item.length > 3)
        target = item[3] ? item[3] : target;

    if (link != null)
    {
        window.open (link, target);
    }

    var prefix = obj.cmPrefix;
    var thisMenu = cmGetThisMenu (obj, prefix);

    var hasChild = (item.length > 5);
    if (hasChild)
    {
        if (cmIsDefaultItem (item))
        {
            if (obj.cmIsMain)
                obj.className = prefix + 'MainItemHover';
            else
                obj.className = prefix + 'MenuItemHover';
        }
    }
}

//////////////////////////////////////////////////////////////////////
//
// Mouse Event Support Utility Functions
//
//////////////////////////////////////////////////////////////////////

//
// move submenu to the appropriate location
//
// @param    obj    the menu item that opens up the subMenu
//        subMenu    the sub menu to be shown
//        orient    the orientation of the subMenu
//
function cmMoveSubMenu (obj, subMenu, orient)
{
    var mode = String (orient);
    var p = subMenu.offsetParent;
    if (mode.charAt (0) == 'h')
    {
        if (mode.charAt (1) == 'b')
            subMenu.style.top = (cmGetYAt (obj, p) + obj.offsetHeight) + 'px';
        else
            subMenu.style.top = (cmGetYAt (obj, p) - subMenu.offsetHeight) + 'px';
        if (mode.charAt (2) == 'r')
            subMenu.style.left = (cmGetXAt (obj, p)) + 'px';
        else
            subMenu.style.left = (cmGetXAt (obj, p) + obj.offsetWidth - subMenu.offsetWidth) + 'px';
    }
    else
    {
        if (mode.charAt (2) == 'r')
            subMenu.style.left = (cmGetXAt (obj, p) + obj.offsetWidth) + 'px';
        else
            subMenu.style.left = (cmGetXAt (obj, p) - subMenu.offsetWidth) + 'px';
        if (mode.charAt (1) == 'b')
            subMenu.style.top = (cmGetYAt (obj, p)) + 'px';
        else
            subMenu.style.top = (cmGetYAt (obj, p) + obj.offsetHeight - subMenu.offsetHeight) + 'px';
        //alert (subMenu.style.top + ', ' + cmGetY (obj) + ', ' + obj.offsetHeight);
    }
}

//
// show the subMenu w/ specified orientation
// also move it to the correct coordinates
//
// @param    obj    the menu item that opens up the subMenu
//        subMenu    the sub menu to be shown
//        orient    the orientation of the subMenu
//
function cmShowSubMenu (obj, prefix, subMenu, orient)
{
    if (!subMenu.cmParentMenu)
    {
        // establish the tree w/ back edge
        var thisMenu = cmGetThisMenu (obj, prefix);
        subMenu.cmParentMenu = thisMenu;
        if (!thisMenu.cmSubMenu)
            thisMenu.cmSubMenu = new Array ();
        //thisMenu.cmSubMenu.push (subMenu);
        thisMenu.cmSubMenu[thisMenu.cmSubMenu.length] = subMenu;
    }

    // position the sub menu
    cmMoveSubMenu (obj, subMenu, orient);
    subMenu.style.visibility = 'visible';

    //
    // On IE, controls such as SELECT, OBJECT, IFRAME (before 5.5)
    // are window based controls.  So, if sub menu and these controls
    // overlap, sub menu would be hid behind them.  Thus, one needs to
    // turn the visibility of these controls off when the
    // sub menu is showing, and turn their visibility back on
    //
    if (document.all)    // it is IE
    {
        subMenu.cmOverlap = new Array ();
/*@cc_on @*/
/*@if (@_jscript_version >= 5.5)
@else @*/
        cmHideControl ("IFRAME", subMenu);
/*@end @*/
        cmHideControl ("SELECT", subMenu);
        cmHideControl ("OBJECT", subMenu);
    }
}

//
// reset all the menu items to class MenuItem in thisMenu
//
function cmResetMenu (thisMenu, prefix)
{
    if (thisMenu.cmItems)
    {
        var i;
        var str;
        var items = thisMenu.cmItems;
        for (i = 0; i < items.length; ++i)
        {
            if (items[i].cmIsMain)
                str = prefix + 'MainItem';
            else
                str = prefix + 'MenuItem';
            if (items[i].className != str)
                items[i].className = str;
        }
    }
}

//
// called by the timer to hide the menu
//
function cmHideMenuTime ()
{
    if (_cmCurrentItem)
    {
        var prefix = _cmCurrentItem.cmPrefix;
        cmHideMenu (cmGetThisMenu (_cmCurrentItem, prefix), null, prefix);
    }
}

//
// hide thisMenu, children of thisMenu, as well as the ancestor
// of thisMenu until currentMenu is encountered.  currentMenu
// will not be hidden
//
function cmHideMenu (thisMenu, currentMenu, prefix)
{
    var str = prefix + 'SubMenu';

    // hide the down stream menus
    if (thisMenu.cmSubMenu)
    {
        var i;
        for (i = 0; i < thisMenu.cmSubMenu.length; ++i)
        {
            cmHideSubMenu (thisMenu.cmSubMenu[i], prefix);
        }
    }

    // hide the upstream menus
    while (thisMenu && thisMenu != currentMenu)
    {
        cmResetMenu (thisMenu, prefix);
        if (thisMenu.className == str)
        {
            thisMenu.style.visibility = 'hidden';
            cmShowControl (thisMenu);
        }
        else
            break;
        thisMenu = cmGetThisMenu (thisMenu.cmParentMenu, prefix);
    }
}

//
// hide thisMenu as well as its sub menus if thisMenu is not
// already hidden
//
function cmHideSubMenu (thisMenu, prefix)
{
    if (thisMenu.style.visibility == 'hidden')
        return;
    if (thisMenu.cmSubMenu)
    {
        var i;
        for (i = 0; i < thisMenu.cmSubMenu.length; ++i)
        {
            cmHideSubMenu (thisMenu.cmSubMenu[i], prefix);
        }
    }
    cmResetMenu (thisMenu, prefix);
    thisMenu.style.visibility = 'hidden';
    cmShowControl (thisMenu);
}

//
// hide a control such as IFRAME
//
function cmHideControl (tagName, subMenu)
{
    var x = cmGetX (subMenu);
    var y = cmGetY (subMenu);
    var w = subMenu.offsetWidth;
    var h = subMenu.offsetHeight;

    var i;
    for (i = 0; i < document.all.tags(tagName).length; ++i)
    {
        var obj = document.all.tags(tagName)[i];
        if (!obj || !obj.offsetParent)
            continue;

        // check if the object and the subMenu overlap

        var ox = cmGetX (obj);
        var oy = cmGetY (obj);
        var ow = obj.offsetWidth;
        var oh = obj.offsetHeight;

        if (ox > (x + w) || (ox + ow) < x)
            continue;
        if (oy > (y + h) || (oy + oh) < y)
            continue;
        //subMenu.cmOverlap.push (obj);
        subMenu.cmOverlap[subMenu.cmOverlap.length] = obj;
        obj.style.visibility = "hidden";
    }
}

//
// show the control hidden by the subMenu
//
function cmShowControl (subMenu)
{
    if (subMenu.cmOverlap)
    {
        var i;
        for (i = 0; i < subMenu.cmOverlap.length; ++i)
            subMenu.cmOverlap[i].style.visibility = "";
    }
    subMenu.cmOverlap = null;
}

//
// returns the main menu or the submenu table where this obj (menu item)
// is in
//
function cmGetThisMenu (obj, prefix)
{
    var str1 = prefix + 'SubMenu';
    var str2 = prefix + 'Menu';
    while (obj)
    {
        if (obj.className == str1 || obj.className == str2)
            return obj;
        obj = obj.parentNode;
    }
    return null;
}

//
// return true if this item is handled using default handlers
//
function cmIsDefaultItem (item)
{
    if (item == _cmSplit || item[0] == _command_no_action_)
        return false;
    return true;
}

//
// returns the object baring the id
//
function cmGetObject (id)
{
    if (document.all)
        return document.all[id];
    return document.getElementById (id);
}

//
// functions that obtain the coordinates of an HTML element
//
function cmGetX (obj)
{
    var x = 0;

    do
    {
        x += obj.offsetLeft;
        obj = obj.offsetParent;
    }
    while (obj);
    return x;
}

function cmGetXAt (obj, elm)
{
    var x = 0;

    while (obj && obj != elm)
    {
        x += obj.offsetLeft;
        obj = obj.offsetParent;
    }
    return x;
}

function cmGetY (obj)
{
    var y = 0;
    do
    {
        y += obj.offsetTop;
        obj = obj.offsetParent;
    }
    while (obj);
    return y;
}

function cmGetYAt (obj, elm)
{
    var y = 0;

    while (obj && obj != elm)
    {
        y += obj.offsetTop;
        obj = obj.offsetParent;
    }
    return y;
}

//
// debug function, ignore :)
//
function cmGetProperties (obj)
{
    if (obj == undefined)
        return 'undefined';
    if (obj == null)
        return 'null';

    var msg = obj + ':\n';
    var i;
    for (i in obj)
        msg += i + ' = ' + obj[i] + '; ';
    return msg;
}