public function route(array $values, $operator)
    {
        if (!in_array($operator, array('=', '!='))) {
            return $this->translation->text('Unsupported operator');
        }

        $existing = $this->route->getList();

        foreach ($values as $pattern) {
            if (empty($existing[$pattern])) {
                return $this->translation->text('@name is unavailable', array(
                    '@name' => $this->translation->text('Condition')));
            }
        }

        return true;
    }