private function snapshotCursorValues(DocumentSnapshot $snapshot, array $orderBy)
    {
        $fieldValues = [];
        foreach ($orderBy as $order) {
            $path = $order['field']['fieldPath'];
            if ($path === self::DOCUMENT_ID) {
                continue;
            }

            $fieldValues[] = $snapshot->get($path);
        }

        $fieldValues[] = $snapshot->reference();
        return $fieldValues;
    }