var SUBNAV_CLASS		= 'subnavContainer';
var SUBNAV_HEADER_CLASS	= 'subnavHeader';

var _subnavContainer	= null;
var _navHideTime		= 10;
var _navTimerStarted	= false;

var navBlocks	= {
	'about':	[
		{ title: 'Bio',				url: '/about/' },
		{ title: 'Contact',			url: '/about/contact/' },
		{ title: 'Press Kit',		url: '/about/press-kit/' }
	],
	'books':	[
		{ title: 'Secret Son',		url: '/secret-son/about' },
		{ title: 'Hope and Other Dangerous Pursuits',	url: '/hope-and-other-dangerous-pursuits/about' }
		
	],
	'writings':	[
		{ title: 'Short Stories',	url: '/writings/short-stories/' },
		{ title: 'Essays',			url: '/writings/essays/' },
		{ title: 'Opinion Pieces',	url: '/writings/opinion-pieces/' },
		{ title: 'Book Reviews',	url: '/writings/book-reviews/' },
		{ title: 'Film Reviews',	url: '/writings/film-reviews/' }
	],
	
	'media': [
		{ title: 'Audio',			url: '/media-audio/' },
		{ title: 'Video',			url: '/media-v/' },
		{ title: 'Print',			url: '/media-print/' }
	]
};

function rollNav( navId )
{
	if ( !navBlocks[ navId ] )
	{
		alert( 'Invalid navigation ID "'+ navId +'"' );
		return;
	}

	if ( !_navTimerStarted )
	{
		_navTimerStarted = true;
		navTimer();
	}
	_navHideTime = 30;
	var parentNavPosition = Position.cumulativeOffset( $('nav-'+ navId) );

	if ( _subnavContainer != null )
		Element.remove( _subnavContainer );
	_subnavContainer = document.createElement( 'div' );
	_subnavContainer.className	= SUBNAV_CLASS;
	var subnavHeader			= document.createElement( 'div' );
	subnavHeader.className		= SUBNAV_HEADER_CLASS;
	var subnavHeaderA			= document.createElement( 'a' );
	subnavHeaderA.href			= $('nav-'+ navId).href;
	subnavHeaderA.innerHTML		= $('nav-'+ navId).innerHTML;
	subnavHeader.appendChild( subnavHeaderA );
	_subnavContainer.appendChild( subnavHeader );

	var subnavData	= navBlocks[ navId ];
	for ( var i = 0; i < subnavData.length; i++ )
	{
		var subnavLink = document.createElement( 'a' );
		subnavLink.className	= 'subnav-link';
		subnavLink.href			= subnavData[i].url;
		subnavLink.innerHTML	= subnavData[i].title;
		_subnavContainer.appendChild( subnavLink );
	}
	_subnavContainer.onmousemove = function() { _navHideTime = 10; };
	_subnavContainer.style.left	= '' + ( parentNavPosition['left'] - 40 ) + 'px';
	$('header').appendChild( _subnavContainer );
}

function navTimer()
{
	_navHideTime--;
	if ( _navHideTime <= 0 )
	{
		_navHideTime = 0;
		if ( _subnavContainer != null )
		{
			Element.remove( _subnavContainer );
			_subnavContainer = null;
		}
	}
	setTimeout( "navTimer()", 100 );
}