public function groups()
    {
        if ($this->groups === null) {
            $ident    = $this->ident();
            $metadata = $this->adminSecondaryMenu();

            $this->groups = [];
            if (isset($metadata[$ident]['groups'])) {
                $groups = $metadata[$ident]['groups'];

                if (is_array($groups)) {
                    $this->setGroups($groups);
                }
            }
        }

        return $this->groups;
    }