public function prepareFileContent($rawContent, array $meta = array())
    {
        // remove meta header
        $metaHeaderPattern = "/^(\/(\*)|---)[[:blank:]]*(?:\r)?\n"
            . "(?:(.*?)(?:\r)?\n)?(?(2)\*\/|---)[[:blank:]]*(?:(?:\r)?\n|$)/s";
        $markdown = preg_replace($metaHeaderPattern, '', $rawContent, 1);

        // replace placeholders
        $markdown = $this->substituteFileContent($markdown, $meta);

        return $markdown;
    }