extractFileToDisk function Null safety

Implementation

Future<void> extractFileToDisk(String inputPath, String outputPath,
    {String? password, bool asyncWrite = false, int? bufferSize}) async {
  Directory? tempDir;
  var archivePath = inputPath;

  var futures = <Future<void>>[];
  if (inputPath.endsWith('tar.gz') || inputPath.endsWith('tgz')) {
    tempDir = Directory.systemTemp.createTempSync('dart_archive');
    archivePath = '${tempDir.path}${Platform.pathSeparator}temp.tar';
    final input = InputFileStream(inputPath);
    final output = OutputFileStream(archivePath, bufferSize: bufferSize);
    GZipDecoder().decodeStream(input, output);
    futures.add(input.close());
    futures.add(output.close());
  } else if (inputPath.endsWith('tar.bz2') || inputPath.endsWith('tbz')) {
    tempDir = Directory.systemTemp.createTempSync('dart_archive');
    archivePath = '${tempDir.path}${Platform.pathSeparator}temp.tar';
    final input = InputFileStream(inputPath);
    final output = OutputFileStream(archivePath, bufferSize: bufferSize);
    BZip2Decoder().decodeBuffer(input, output: output);
    futures.add(input.close());
    futures.add(output.close());
  }

  if (futures.isNotEmpty) {
    await Future.wait(futures);
    futures.clear();
  }

  Archive archive;
  if (archivePath.endsWith('tar')) {
    final input = InputFileStream(archivePath);
    archive = TarDecoder().decodeBuffer(input);
  } else if (archivePath.endsWith('zip')) {
    final input = InputFileStream(archivePath);
    archive = ZipDecoder().decodeBuffer(input, password: password);
  } else {
    throw ArgumentError.value(inputPath, 'inputPath',
        'Must end tar.gz, tgz, tar.bz2, tbz, tar or zip.');
  }

  for (final file in archive.files) {
    final filePath = '$outputPath${Platform.pathSeparator}${file.name}';

    if (!isWithinOutputPath(outputPath, filePath)) {
      continue;
    }

    if (!file.isFile) {
      Directory(filePath).createSync(recursive: true);
      continue;
    }

    if (asyncWrite) {
      final output = File(filePath);
      final f = await output.create(recursive: true);
      final fp = await f.open(mode: FileMode.write);
      final bytes = file.content as List<int>;
      await fp.writeFrom(bytes);
      file.clear();
      futures.add(fp.close());
    } else {
      final output = OutputFileStream(filePath, bufferSize: bufferSize);
      try {
        file.writeContent(output);
      } catch (err) {
        //
      }
      futures.add(output.close());
    }
  }

  if (futures.isNotEmpty) {
    await Future.wait(futures);
    futures.clear();
  }

  futures.add(archive.clear());

  if (futures.isNotEmpty) {
    await Future.wait(futures);
    futures.clear();
  }

  if (tempDir != null) {
    futures.add(tempDir.delete(recursive: true));
  }

  if (futures.isNotEmpty) {
    await Future.wait(futures);
    futures.clear();
  }
}