private function handleUseragentGroup(Lexer $lexer) : int
    {
        $useragentPosition = 0;

        do {
            $code = $lexer->lex();

            if (self::JSON_OBJECT_START === $code) {
                $code = $this->handleUseragentBlock($lexer, $useragentPosition);
                ++$useragentPosition;
            }
        } while (self::JSON_ARRAY_END !== $code);

        return $lexer->lex();
    }