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 ) {
	// apply the method to IE
	if ( Br.IE ) {
		//attachEvent dont work properly with this
		eval('target.on'+eventName+'=functionName');
	}
	// apply the method to DOM compliant browsers
	else {
		target.addEventListener( eventName , functionName , true ); // true is important for Opera7
	}
}

// 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';
	}
}