transmit method

@override Future<Uint8List> transmit(Uint8List bytes)

Sends command and returns the response, data then status bytes.

Throws a CardTransportException when the card cannot be reached.

Implementation

@override
Future<Uint8List> transmit(Uint8List bytes) async {
  if (latency > Duration.zero) await Future<void>.delayed(latency);
  if (!_inserted) {
    throw const CardTransportException('No chip on the simulated reader');
  }
  final CommandApdu command;
  try {
    command = CommandApdu.parse(bytes);
  } on FormatException {
    return _status(0x6700);
  }
  final session = _session;
  if (command.cla & 0x0C == 0x0C) {
    if (session == null) return _status(0x6988);
    final plain = session.unwrap(command);
    if (plain == null) {
      _reset();
      return _status(0x6988);
    }
    final (data, status) = _process(plain);
    final answer = session.wrap(data, status);
    // Chip Authentication switches keys after its answer.
    if (identical(_session, session) && session.next != null) {
      _session = session.next;
    }
    return answer;
  }
  // A plain command ends secure messaging, as on a real chip.
  _session = null;
  final (data, status) = _process(command);
  return concat([data, _status(status)]);
}