var ie5 = ( document.getElementById && document.all );
//var ie6 = ( document.getElementById && document.all );
var moz = ( document.getElementById &&! document.all );
var opera = ( navigator.userAgent.indexOf( 'Opera' ) != -1);
var wait, goIn, intRightNow, inUse;
if ( opera ) ie5 = false;

function getObject( obj ) {
	var strObj;
	if ( document.all ) {
		strObj = document.all.item( obj );
	}
	else if (document.getElementById ) {
		strObj = document.getElementById( obj );
	}
	//alert(strObj);
	return strObj;
}



function swapNav( intNavSpan ) {
	// IF MENU OPTION ALREADY SELECTED - EXIT FUNCTION
	if ( getObject( 'nav' + intNavSpan ).style.display == 'inline' ) {
		return;
	}
	
	// IF MENU OPTION SELECTED NOT ALREADY SELECTED	
	if ( intNavSpan != intRightNow ) {
		// IF VAR WAIT NOT NULL - MAKE IT NULL
		if ( typeof wait != 'undefined' ) {
			clearTimeout( wait ); 
		}
		// IF VAR goIn NOT NULL - MAKE IT NULL
		if ( typeof goIn != 'undefined' ) { clearTimeout( goIn ); }
		
		//REGISTER THE CURRENT MENU
		intRightNow = intNavSpan;
		inUse = '';
		swapNav( intNavSpan );
		return;
	}
	
	if ( inUse != '' ) {
		wait = setTimeout( 'swapNav( ' + intNavSpan + ' )', 20);
		return;
	}
	fader( 'navRowSub', 'out' );
	if ( inUse != '' ) {
		wait = setTimeout( 'swapNav( ' + intNavSpan + ' )', 20);
		return;
	}
	
	var maxInt = 7;
	// MAKE ALL SUBMENUS INVISIBLE
	for ( var i = 1; i <= maxInt; i++ ) {
		getObject( 'nav' + i ).style.display = 'none';
	}
	// MAKE SELECTED SUBMENU VISIBLE
	getObject( 'nav' + intNavSpan ).style.display = 'inline';
	fader( 'navRowSub', 'in' );	
}

function fader( objID, dir )  {
	var fade_index;
	if ( inUse !=  '' && inUse != dir ) {
		return;
	}
	if ( ie5 || moz ) {
		inUse = dir;
		
		if( ie5 ) {
			fade_index = getObject( objID ).filters.alpha.opacity;
		}
		if( moz ) {
			fade_index = getObject( objID ).style.MozOpacity * 100;
		}
		fade_index = dir == 'in' ? fade_index + 20 : fade_index - 20;
		index_limit = dir == 'in' ? 100 : 0;
		
		if( ie5 ) {
			getObject( objID ).filters.alpha.opacity = fade_index;
		}		
		if( moz ) {
			getObject( objID ).style.MozOpacity = fade_index / 100;
		}
		
		goIn = setTimeout('fader(\'' + objID + '\', \'' + dir + '\')', 20);
		
		if( ( dir == 'in' && fade_index >= index_limit ) || ( dir == 'out' && fade_index <= index_limit ) ) {
			clearTimeout( goIn );
			inUse = '';
		}
	}
}