BlueWallet/class/hd-legacy-breadwallet-wallet.js

import { AbstractHDElectrumWallet } from './abstract-hd-electrum-wallet';
import bip39 from 'bip39';
const bip32 = require('bip32');
const bitcoinjs = require('bitcoinjs-lib');

/**
 * HD Wallet (BIP39).
 * In particular, Breadwallet-compatible (Legacy addresses)
 */
export class HDLegacyBreadwalletWallet extends AbstractHDElectrumWallet {
  static type = 'HDLegacyBreadwallet';
  static typeReadable = 'HD Legacy Breadwallet (P2PKH)';

  /**
   * @see https://github.com/bitcoinjs/bitcoinjs-lib/issues/584
   * @see https://github.com/bitcoinjs/bitcoinjs-lib/issues/914
   * @see https://github.com/bitcoinjs/bitcoinjs-lib/issues/997
   */
  getXpub() {
    if (this._xpub) {
      return this._xpub; // cache hit
    }
    const mnemonic = this.secret;
    const seed = bip39.mnemonicToSeed(mnemonic);
    const root = bip32.fromSeed(seed);

    const path = "m/0'";
    const child = root.derivePath(path).neutered();
    this._xpub = child.toBase58();

    return this._xpub;
  }

  _getExternalAddressByIndex(index) {
    index = index * 1; // cast to int
    if (this.external_addresses_cache[index]) return this.external_addresses_cache[index]; // cache hit

    const node = bitcoinjs.bip32.fromBase58(this.getXpub());
    const address = bitcoinjs.payments.p2pkh({
      pubkey: node.derive(0).derive(index).publicKey,
    }).address;

    return (this.external_addresses_cache[index] = address);
  }

  _getInternalAddressByIndex(index) {
    index = index * 1; // cast to int
    if (this.internal_addresses_cache[index]) return this.internal_addresses_cache[index]; // cache hit

    const node = bitcoinjs.bip32.fromBase58(this.getXpub());
    const address = bitcoinjs.payments.p2pkh({
      pubkey: node.derive(1).derive(index).publicKey,
    }).address;

    return (this.internal_addresses_cache[index] = address);
  }

  _getExternalWIFByIndex(index) {
    return this._getWIFByIndex(false, index);
  }

  _getInternalWIFByIndex(index) {
    return this._getWIFByIndex(true, index);
  }

  /**
   * Get internal/external WIF by wallet index
   * @param {Boolean} internal
   * @param {Number} index
   * @returns {*}
   * @private
   */
  _getWIFByIndex(internal, index) {
    const mnemonic = this.secret;
    const seed = bip39.mnemonicToSeed(mnemonic);
    const root = bitcoinjs.bip32.fromSeed(seed);
    const path = `m/0'/${internal ? 1 : 0}/${index}`;
    const child = root.derivePath(path);

    return child.keyPair.toWIF();
  }
}