twonly-app/lib/src/utils/qr.dart

import 'package:fixnum/fixnum.dart';
import 'package:flutter/foundation.dart';
import 'package:twonly/globals.dart';
import 'package:twonly/src/model/protobuf/client/generated/qr.pb.dart';
import 'package:twonly/src/services/signal/identity.signal.dart';
import 'package:twonly/src/services/signal/utils.signal.dart';
import 'package:twonly/src/utils/log.dart';

Future<Uint8List> getProfileQrCodeData() async {
  final signalIdentity = (await getSignalIdentity())!;

  final signalStore = await getSignalStoreFromIdentity(signalIdentity);

  final signedPreKey = (await signalStore.loadSignedPreKeys())[0];

  final publicProfile = PublicProfile(
    userId: Int64(gUser.userId),
    username: gUser.username,
    publicIdentityKey:
        (await signalStore.getIdentityKeyPair()).getPublicKey().serialize(),
    registrationId: Int64(signalIdentity.registrationId),
    signedPrekey: signedPreKey.getKeyPair().publicKey.serialize(),
    signedPrekeySignature: signedPreKey.signature,
    signedPrekeyId: Int64(signedPreKey.id),
  );

  final data = publicProfile.writeToBuffer();

  final qrEnvelope = QREnvelope(
    type: QREnvelope_Type.PublicProfile,
    data: data,
  );

  return qrEnvelope.writeToBuffer();
}

PublicProfile? parseQrCodeData(Uint8List rawBytes) {
  try {
    final envelop = QREnvelope.fromBuffer(rawBytes);
    if (envelop.type == QREnvelope_Type.PublicProfile) {
      return PublicProfile.fromBuffer(envelop.data);
    }
  } catch (e) {
    Log.warn(e);
  }
  return null;
}