generateQrCode method

Future<QRCode?> generateQrCode()

Implementation

Future<QRCode?> generateQrCode() async {
  final data = Uint8Buffer();
  // why 11? https://github.com/sdn-org/sdn-js-sdk/commit/275ea6aacbfc6623e7559a7649ca5cab207903d9
  randomSharedSecretForQRCode =
      encodeBase64Unpadded(uc.secureRandomBytes(11));

  final mode = getOurQRMode();
  data.addAll(ascii.encode(prefix));
  data.add(version);
  data.add(mode.code);
  final encodedTxnId = utf8.encode(transactionId!);
  final txnIdLen = encodedTxnId.length;
  final tmpBuf = Uint8List(2);
  ByteData.view(tmpBuf.buffer).setUint16(0, txnIdLen);
  data.addAll(tmpBuf);
  data.addAll(encodedTxnId);
  final keys = await getKeys(mode);
  if (keys != null) {
    data.addAll(base64decodeUnpadded(keys.$1));
    data.addAll(base64decodeUnpadded(keys.$2));
  } else {
    return null;
  }

  data.addAll(base64decodeUnpadded(randomSharedSecretForQRCode!));
  return QRCode(randomSharedSecretForQRCode!, data);
}