+function nav(&$a) {
+
+ /**
+ *
+ * Build page header and site navigation bars
+ *
+ */
+
+ if(!(x($a->page,'nav')))
+ $a->page['nav'] = '';
+
+ /**
+ * Placeholder div for popup panel
+ */
+
+ $a->page['nav'] .= '<div id="panel" style="display: none;"></div>' ;
+
+ /**
+ *
+ * Our network is distributed, and as you visit friends some of the
+ * sites look exactly the same - it isn't always easy to know where you are.
+ * Display the current site location as a navigation aid.
+ *
+ */
+
+ $myident = ((is_array($a->user) && isset($a->user['nickname'])) ? $a->user['nickname'] . '@' : '');
+
+ $sitelocation = $myident . substr($a->get_baseurl(),strpos($a->get_baseurl(),'//') + 2 );
+
+
+ // nav links: array of array('href', 'text', 'extra css classes')
+ $nav = Array();
+
+ /**
+ * Display login or logout
+ */
+
+ if(local_user()) {
+ $nav['logout'] = Array('logout',t('Logout'), "");
+ }
+ else {
+ $nav['login'] = Array('login',t('Login'), ($a->module == 'login'?'nav-selected':''));
+ }
+
+
+ /**
+ * "Home" should also take you home from an authenticated remote profile connection
+ */
+
+ $homelink = ((x($_SESSION,'visitor_home')) ? $_SESSION['visitor_home'] : '');
+
+ if(($a->module != 'home') && (! (local_user())))
+ $nav['home'] = array($homelink, t('Home'), "");
+
+
+ if(($a->config['register_policy'] == REGISTER_OPEN) && (! local_user()) && (! remote_user()))
+ $nav['register'] = array('register',t('Register'), "");
+
+ $help_url = $a->get_baseurl() . '/help';