if (!document.getElementById && document.all) {
	document.getElementById = function(id) {
		return document.all[id];
	}
}

// navigates content
function PlayerNavigator() {

	// id of the node currently selected
	var m_index = new Array();
	var m_current_item = 0;
	
	function PlayerNavigator_Load() {
		for (var i = 0; i < document.links.length; i++) {
			m_index[i] = new Object();
			m_index[i].id = document.links[i].id;
			m_index[i].href = document.links[i].href;
			m_index[i].type = document.links[i].type;
		}
	}
	
	function PlayerNavigator_TurnPage( direction, resume ) {
		if (m_index[m_current_item].type == 'imsqti_xmlv1p1' && !resume) {
			top.frames['content'].turnPage(direction);
		}
		else {
			this.GotoPage(m_current_item + direction);
		}
	}
	
	function PlayerNavigator_FindPage( page ) {
		for (var i = 0; i < m_index.length; i++) {
			if (m_index[i].id == page) return i;
		}
		return 0;
	}
	
	function PlayerNavigator_GotoPage( page ) {
		if (page < m_index.length && page >= 0) {
				this.SelectNode(false);
				m_current_item = page;
				top.frames['content'].location = m_index[m_current_item].href;
				this.SelectNode(true);
		}
	}
	
	function PlayerNavigator_SelectNode( b ) {
		var c = b ? "navcurrent" : "nav";
		var e = document.getElementById(m_index[m_current_item].id);
		var p = e.parentElement ? e.parentElement : e.parentNode;
		p.className = c;
	}
	
	PlayerNavigator.prototype.Load = PlayerNavigator_Load;
	PlayerNavigator.prototype.FindPage = PlayerNavigator_FindPage;
	PlayerNavigator.prototype.GotoPage = PlayerNavigator_GotoPage;
	PlayerNavigator.prototype.TurnPage = PlayerNavigator_TurnPage;
	PlayerNavigator.prototype.SelectNode = PlayerNavigator_SelectNode;
}

var player_navigator = new PlayerNavigator();

function turnPage( direction ) {
	player_navigator.TurnPage(direction, false);
}

function resume( direction ) {
	player_navigator.TurnPage(direction, true);
}

function navclick( e ) {
	var n = player_navigator.FindPage(e.id);
	player_navigator.GotoPage(n);
	var p = e.parentElement ? e.parentElement : e.parentNode;
	p.className = "navcurrent";
}