public function getCdrFile(): string
    {
        $name = static::filterFilename($this->name);

        // get attributes
        $comment = $this->opt->getComment();

        // get dos timestamp
        $time = static::dosTime($this->opt->getTime()->getTimestamp());

        $footer = $this->buildZip64ExtraBlock();

        $fields = [
            ['V', ZipStream::CDR_FILE_SIGNATURE],   // Central file header signature
            ['v', ZipStream::ZIP_VERSION_MADE_BY],  // Made by version
            ['v', $this->version->getValue()],      // Extract by version
            ['v', $this->bits],                     // General purpose bit flags - data descriptor flag set
            ['v', $this->method->getValue()],       // Compression method
            ['V', $time],                           // Timestamp (DOS Format)
            ['V', $this->crc],                      // CRC32
            ['V', $this->zlen->getLowFF()],         // Compressed Data Length
            ['V', $this->len->getLowFF()],          // Original Data Length
            ['v', strlen($name)],                   // Length of filename
            ['v', strlen($footer)],                 // Extra data len (see above)
            ['v', strlen($comment)],                // Length of comment
            ['v', 0],                               // Disk number
            ['v', 0],                               // Internal File Attributes
            ['V', 32],                              // External File Attributes
            ['V', $this->ofs->getLowFF()]           // Relative offset of local header
        ];

        // pack fields, then append name and comment
        $header = ZipStream::packFields($fields);

        return $header . $name . $footer . $comment;
    }