public function execute()
 {
     // only allowed to global admin
     if (!wa()->getUser()->getRights('webasyst', 'backend')) {
         throw new waRightsException('Access denied.');
     }
     $collection = new contactsCollection('users/all');
     $group = null;
     $memberIds = array();
     if ($id = waRequest::get('id')) {
         $group_model = new waGroupModel();
         $group = $group_model->getById($id);
     }
     if ($group) {
         $user_groups_model = new waUserGroupsModel();
         $memberIds = $user_groups_model->getContactIds($id);
     }
     $users = $collection->getContacts('id,name');
     // array(id => array(id=>...,name=>...))
     $members = array();
     foreach ($memberIds as $mid) {
         if (isset($users[$mid])) {
             $members[$mid] = $users[$mid];
             unset($users[$mid]);
         }
     }
     usort($members, array($this, '_cmp'));
     usort($users, array($this, '_cmp'));
     $this->view->assign('group', $group);
     $this->view->assign('notIncluded', $users);
     $this->view->assign('members', $members);
 }