validateFileIsZip example

    private const HEADER_SIGNATURE = '504b0304';

    public static function openZip(string $filename): \ZipArchive
    {
        $stream = new \ZipArchive();

        if (!file_exists($filename)) {
            throw PluginException::cannotExtractNoSuchFile($filename);
        }

        if (!self::validateFileIsZip($filename)) {
            throw PluginException::cannotExtractInvalidZipFile($filename);
        }

        if (($retVal = $stream->open($filename)) !== true) {
            throw PluginException::cannotExtractZipOpenError(self::getErrorMessage($retVal, $filename));
        }

        return $stream;
    }

    private static function getErrorMessage(int $retVal, string $file): string
    {