convert method

@override Future<List<int>> convert(List<int> input, { Uint8List? possibleBuffer, Mac? expectedMac, int? chunkSize, })

Adds input to the sequence of converted bytes and finishes converting all bytes.

If expectedMac is non-null, then the method will throw SecretBoxAuthenticationError if the computed MAC does match.

If possibleBuffer is non-null, the method is allowed (but not required) to write the output to it. The buffer can be the same as input. Otherwise the method will allocate memory for the output.

Implementation

@override
Future<List<int>> convert(
  List<int> input, {
  Uint8List? possibleBuffer,
  Mac? expectedMac,
  int? chunkSize,
}) async {
  if (!_isInitialized) {
    throw StateError('Not initialized');
  }
  final outputChunks = <List<int>>[];
  chunkSize ??= defaultChunkSize;
  if (chunkSize < 0) {
    //
    // Do not split the input
    //
    final outputChunk = convertChunkSync(
      input,
      possibleBuffer: possibleBuffer,
    );
    outputChunks.add(outputChunk);
  } else {
    //
    // Split the input
    //
    if (chunkSize < 64) {
      throw ArgumentError.value(chunkSize, 'chunkSize');
    }
    if (input is! Uint8List) {
      input = Uint8List.fromList(input);
      possibleBuffer = input;
    }
    for (var i = 0; i < input.length; i += chunkSize) {
      // Pause to avoid blocking the event loop.
      if (i > 0) {
        await Future.delayed(const Duration(milliseconds: 1));
      }
      final thisChunkSize = min(chunkSize, input.length - i);
      final inputChunk = input.buffer.asUint8List(
        input.offsetInBytes + i,
        thisChunkSize,
      );
      final outputChunk = convertChunkSync(
        inputChunk,
        possibleBuffer: possibleBuffer,
      );
      outputChunks.add(outputChunk);
    }
  }
  final suffix = beforeClose();
  if (suffix.isNotEmpty) {
    macSink.add(suffix);
    outputChunks.add(suffix);
  }
  macSink.close();
  final mac = await macSink.mac();
  _mac = mac;
  if (expectedMac != null && mac != expectedMac) {
    throw SecretBoxAuthenticationError();
  }
  return _concatenate(outputChunks);
}