signHash method

@override Future<Uint8List> signHash(Uint8List hash32)

Sign a raw 32-byte hash. Returns 65-byte signature (r + s + v).

Implementation

@override
Future<Uint8List> signHash(Uint8List hash32) async {
  if (hash32.length != 32) {
    throw ArgumentError('Hash must be 32 bytes, got ${hash32.length}');
  }
  final sig = RecoverableEcdsaSig.sign(hash32, _key.bytes);
  final out = Uint8List(65);
  out.setRange(0, 64, sig.bytes);
  out[64] = sig.recId + 27;
  return out;
}