/**
  * @return string
  */
 public function admin()
 {
     Piwik::checkUserHasSuperUserAccess();
     $view = new View('@LoginLdap/index');
     ControllerAdmin::setBasicVariablesAdminView($view);
     if (!function_exists('ldap_connect')) {
         $notification = new Notification(Piwik::translate('LoginLdap_LdapFunctionsMissing'));
         $notification->context = Notification::CONTEXT_ERROR;
         $notification->type = Notification::TYPE_PERSISTENT;
         Notification\Manager::notify('LoginLdap_LdapFunctionsMissing', $notification);
     }
     $this->setBasicVariablesView($view);
     $serverNames = Config::getServerNameList() ?: array();
     $view->servers = array();
     if (empty($serverNames)) {
         try {
             $serverInfo = ServerInfo::makeFromOldConfig()->getProperties();
             $serverInfo['name'] = 'server';
             $view->servers[] = $serverInfo;
         } catch (Exception $ex) {
             // ignore
         }
     } else {
         foreach ($serverNames as $server) {
             $serverConfig = Config::getServerConfig($server);
             if (!empty($serverConfig)) {
                 $serverConfig['name'] = $server;
                 $view->servers[] = $serverConfig;
             }
         }
     }
     $view->ldapConfig = Config::getPluginOptionValuesWithDefaults();
     $view->isLoginControllerActivated = PluginManager::getInstance()->isPluginActivated('Login');
     $view->updatedFromPre30 = Option::get('LoginLdap_updatedFromPre3_0');
     return $view->render();
 }