DID Wallet 助记词生成钱包规则是什么？

static getAddressFromMnemonic(mnemonic: string): string {
    if (!this.validateMnemonic(mnemonic)) {
      throw new Error('Invalid mnemonic');
    }
    const secretKey = this.generateSecretKeyFromMnemonic(mnemonic);
    const wallet = fromSecretKey(secretKey);
    return wallet.address;
  }
  
  private static generateSecretKeyFromMnemonic(mnemonic: string): Uint8Array {
    const seed = bip39.mnemonicToSeedSync(mnemonic);
    const hash = Hasher.SHA3.hash256('DIDMAIL').toString('hex');
    const s1 = parseInt(hash.slice(0, 8), 16) % 2147483648; // 2^31
    const s2 = parseInt(hash.slice(8, 16), 16) % 2147483648; // 2^31
    const derivationPath = `m/44'/260'/${s1}'/${s2}'/0'`;
    const { key } = ed25519.derivePath(derivationPath, seed.toString('hex'));
    const keyPair = nacl.sign.keyPair.fromSeed(toUint8Array(key));
    return keyPair.secretKey;
  }