var timeout = 500;
var ua = navigator.userAgent.toLowerCase(); 
var isIE = ( (ua.indexOf('msie') != -1) && (ua.indexOf('opera') == -1) && (ua.indexOf('webtv') == -1) ); 

// this fonction apply the CSS style and the event
function initMenu() {
	// a test to avoid some browser like IE4, Opera 6, and IE Mac
	if (Br.DOM) {
		// get some element
		var menu = document.getElementById('xmenu'); // the root element
		var lis = menu.getElementsByTagName('li'); // all the li
		// i am searching for ul element in li element
		for ( var i=0; i<lis.length; i++ ) {
			// is there a ul element ?
			if ( lis.item(i).getElementsByTagName('ul').length > 0 ) {
				// improve IE key navigation
				if ( Br.IE ) {addAnEvent(lis.item(i),'keyup',show); }
				// link events to list item
				addAnEvent(lis.item(i),'mouseover',show);
				addAnEvent(lis.item(i),'mouseout',timeoutHide);
				addAnEvent(lis.item(i),'blur',timeoutHide);
				addAnEvent(lis.item(i),'focus',show);
				  
				// add an id to list item
				lis.item(i).id = "li"+i;
				eval("timeoutli" + i + " = false;");
			}
		}
	}	
}

function addAnEvent( target, eventName, functionName ) {
  var browserVer=parseInt(navigator.appVersion); 

  // zjistim si verzi IE, pokud se nejedna o IE = -1
  var ieVer = getInternetExplorerVersion();

  // apply the method to IE
  if ( Br.IE || ieVer == 9) {
    
    //attachEvent dont work properly with this
    eval('target.on'+eventName+'=functionName');
  } else {
    // apply the method to DOM compliant browsers
    try{
      target.addEventListener( eventName , functionName , true ); // true is important for Opera7
    }catch(e){
      //alert(e.Message + " eventName: "+  eventName + " functionName: " + functionName );
    }
  }
}

// hide the first ul element of the current element
function timeoutHide() {
  // start the timeout
	try { eval( "timeout" + this.id + " = window.setTimeout('hideUlUnder( \"" + this.id + "\" )', " + timeout + " );"); } catch(e) {}
}

// hide the ul elements under the element identified by id
function hideUlUnder( id ) {   
	if (document.getElementById(id)) {
		document.getElementById(id).className = document.getElementById(id).className.replace("sel","");;
		document.getElementById(id).getElementsByTagName('ul')[0].style.visibility = 'hidden';
		SelectHide('visible');
	}
}

// show the first ul element found under this element
function show() {
	// show the sub menu
	this.getElementsByTagName('ul')[0].style.visibility = 'visible';
	// clear the timeout
	//SelectHide('hidden');
	this.className+=" sel"; // pro zapamatovani nadrazeneho
	try { if (eval("timeout"+ this.id)) eval ( "clearTimeout( timeout"+ this.id +");" ); } catch(e) {} 
	hideAllOthersUls( this );
}

// hide all ul on the same level of  this list item
function hideAllOthersUls( currentLi ) {
	var ul = currentLi.parentNode;
	for ( var i=0; i<ul.childNodes.length; i++ ) {
		if ( ul.childNodes[i].id && ul.childNodes[i].id != currentLi.id ) {
			hideUlUnderLi( ul.childNodes[i] );
		}
	}
}

// hide all the ul wich are in the li element
function hideUlUnderLi( li ) {
	li.className = li.className.replace("sel","");
  var uls = li.getElementsByTagName('ul');
  for ( var i=0; i<uls.length; i++ ) {
  	uls.item(i).style.visibility = 'hidden';
	}
} 

function getInternetExplorerVersion()
// Returns the version of Internet Explorer or a -1
// (indicating the use of another browser).
{
  var rv = -1; // Return value assumes failure.
  if (navigator.appName == 'Microsoft Internet Explorer')
  {
    var ua = navigator.userAgent;
    var re  = new RegExp("MSIE ([0-9]{1,}[\.0-9]{0,})");
    if (re.exec(ua) != null)
      rv = parseFloat( RegExp.$1 );
  }
  return rv;
}
function checkVersion()
{
  var msg = "You're not using Internet Explorer.";
  var ver = getInternetExplorerVersion();

  if ( ver > -1 )
  {
    if ( ver >= 8.0 ) 
      msg = "You're using a recent copy of Internet Explorer."
    else
      msg = "You should upgrade your copy of Internet Explorer.";
  }
  alert( msg );
}