hash-wallet/cw_evm/lib/hardware/evm_chain_bitbox_credentials.dart

import 'dart:async';
import 'dart:typed_data';

import 'package:bitbox_flutter/bitbox_manager.dart';
import 'package:cw_core/hardware/device_not_connected_exception.dart' as exception;
import 'package:web3dart/crypto.dart';
import 'package:web3dart/web3dart.dart';

class EvmBitboxCredentials extends CredentialsWithKnownAddress {
  final String _address;

  BitboxManager? bitboxManager;
  String? derivationPath;

  EvmBitboxCredentials(this._address);

  @override
  EthereumAddress get address => EthereumAddress.fromHex(_address);

  void setBitbox(BitboxManager connection, [String? derivationPath_]) {
    bitboxManager = connection;
    derivationPath = derivationPath_ ?? "m/44'/60'/0'/0/0";
  }

  @override
  MsgSignature signToEcSignature(Uint8List payload, {int? chainId, bool isEIP1559 = false}) =>
      throw UnimplementedError("EvmLedgerCredentials.signToEcSignature");

  @override
  Future<MsgSignature> signToSignature(Uint8List payload,
      {int? chainId, bool isEIP1559 = false}) async {
    if (bitboxManager == null) {
      throw exception.DeviceNotConnectedException();
    }

    if (isEIP1559) payload = payload.sublist(1);
    final sig = await bitboxManager!
        .signETHRLPTransaction(chainId ?? 1, derivationPath!, bytesToHex(payload), isEIP1559);

    final r = bytesToHex(sig.sublist(0, 32));
    final s = bytesToHex(sig.sublist(32, 32 + 32));
    final v = sig.last.toInt();

    if (isEIP1559) {
      return MsgSignature(BigInt.parse(r, radix: 16), BigInt.parse(s, radix: 16), v);
    }

    var truncChainId = chainId ?? 1;
    while (truncChainId.bitLength > 32) {
      truncChainId >>= 8;
    }

    final truncTarget = truncChainId * 2 + 35;

    int parity = v;
    if (truncTarget & 0xff == v) {
      parity = 0;
    } else if ((truncTarget + 1) & 0xff == v) {
      parity = 1;
    }

    // https://github.com/ethereumjs/ethereumjs-util/blob/8ffe697fafb33cefc7b7ec01c11e3a7da787fe0e/src/signature.ts#L26
    final chainIdV = chainId != null ? (parity + (chainId * 2 + 35)) : parity;

    return MsgSignature(BigInt.parse(r, radix: 16), BigInt.parse(s, radix: 16), chainIdV);
  }

  @override
  Future<Uint8List> signPersonalMessage(Uint8List payload, {int? chainId}) async {
    if (isNotConnected) throw exception.DeviceNotConnectedException();
    return await bitboxManager!.signETHMessage(chainId ?? 1, derivationPath!, payload);
  }

  @override
  Uint8List signPersonalMessageToUint8List(Uint8List payload, {int? chainId}) =>
      throw UnimplementedError("EvmLedgerCredentials.signPersonalMessageToUint8List");

  bool get isNotConnected => bitboxManager == null;
}