protected function prepareMessage($message)
    {
        list($text, $level, $category, $timestamp) = $message;

        $level = Logger::getLevelName($level);
        $timestamp = date('c', $timestamp);

        $result = ArrayHelper::merge(
            $this->parseText($text),
            ['level' => $level, 'category' => $category, '@timestamp' => $timestamp]
        );

        if (isset($message[4]) === true) {
            $result['trace'] = $message[4];
        }

        return $result;
    }