decode method

@override List<int> decode(String mnemonic)

Decodes an Electrum V1 mnemonic string into a List<int> representing entropy.

-mnemonic: The Electrum V1 mnemonic string to decode.

Implementation

@override
List<int> decode(String mnemonic) {
  /// Parse the mnemonic into an Electrum V1 mnemonic object
  final mnemonicObj = ElectrumV1Mnemonic.fromString(mnemonic);

  /// Get the number of words in the mnemonic
  final wCount = mnemonicObj.wordsCount();

  if (wCount != ElectrumV1WordsNum.wordsNum12.value) {
    throw ArgumentException.invalidOperationArguments(
      "decode",
      name: "mnemonic",
      reason: "Invalid mnemonic length.",
    );
  }
  // Detect language if it was not specified at construction
  final wordsList = findLanguage(mnemonicObj).$1;

  // Get words from the mnemonic
  final words = mnemonicObj.toList();

  // Consider 3 words at a time, 3 words represent 4 bytes
  List<int> entropyBytes = List.empty();
  for (int i = 0; i < words.length ~/ 3; i++) {
    final word1 = words[i * 3];
    final word2 = words[i * 3 + 1];
    final word3 = words[i * 3 + 2];
    entropyBytes = [
      ...entropyBytes,
      ...MnemonicUtils.wordsToBytesChunk(word1, word2, word3, wordsList),
    ];
  }

  return entropyBytes;
}