hash property

@override Uint8List get hash

Implementation

@override
Uint8List get hash {

  // Remove OP_CODESEPERATOR from the script code
  final correctedScriptSig = Script(
    scriptCode.ops.where((op) => !op.match(_codeseperator)),
  ).compiled;

  // If there is no matching output for SIGHASH_SINGLE, then return all null
  // bytes apart from the last byte that should be 1
  if (hashType.single && inputN >= tx.outputs.length) return _hashOne;

  // Create modified transaction for obtaining a signature hash

  final modifiedInputs = (
    hashType.anyOneCanPay ? [tx.inputs[inputN]] : tx.inputs
  ).asMap().map(
    (index, input) {
      final isThisInput = hashType.anyOneCanPay || index == inputN;
      return MapEntry(
        index,
        RawInput(
          prevOut: input.prevOut,
          // Use the corrected previous output script for the input being signed
          // and blank scripts for all the others
          scriptSig: isThisInput ? correctedScriptSig : Uint8List(0),
          // Make sequence 0 for other inputs unless using SIGHASH_ALL
          sequence: isThisInput || hashType.all ? input.sequence : 0,
        ),
      );
    }
  ).values;

  final modifiedOutputs = hashType.all ? tx.outputs : (
    hashType.none ? <Output>[] : [
      // Single output
      // Include blank outputs upto output index
      ...Iterable.generate(inputN, (i) => Output.blank()),
      tx.outputs[inputN],
    ]
  );

  final modifiedTx = Transaction(
    version: tx.version,
    inputs: modifiedInputs,
    outputs: modifiedOutputs,
    locktime: tx.locktime,
  );

  // Add sighash type onto the end
  final bytes = Uint8List(modifiedTx.size + 4);
  final writer = BytesWriter(bytes);
  modifiedTx.write(writer);
  writer.writeUInt32(hashType.value);

  // Use sha256d for signature hash
  return sha256DoubleHash(bytes);

}