MSafe wallet account creation

msafe.ts

import { PublicKey, SIGNATURE_FLAG_TO_SCHEME } from '@mysten/sui.js/cryptography';
import { Ed25519PublicKey } from '@mysten/sui.js/keypairs/ed25519';
import { MultiSigPublicKey } from '@mysten/sui.js/multisig';

import { OwnerWeightPubKey, PublicKeyWithSchema, Weight } from '@/types';

export const NONCE_PREFIX_MAX_SIZE = 16;
export const NONCE_PK_PREFIX = 'maven';
export const NONCE_PK_WEIGHT = 1;

export function computeMSafeAddress(input: {
  owners: OwnerWeightPubKey[];
  threshold: Weight;
  nonce: number | undefined;
}): string {
  const { owners, threshold, nonce } = input;
  const pks = owners.map((owner) => ({
    publicKey: owner.publicKey,
    weight: owner.weight,
  }));
  if (nonce !== undefined) {
    // append nonce public key, weight is 1 because 0 is not allowed
    pks.push({
      publicKey: noncePublicKey(nonce).publicKey,
      weight: NONCE_PK_WEIGHT,
    });
  }
  return MultiSigPublicKey.fromPublicKeys({ threshold, publicKeys: pks }).toSuiAddress();
}

export function noncePublicKeyWithWeight(nonce: number) {
  return {
    pubKey: noncePublicKey(nonce).publicKey,
    weight: NONCE_PK_WEIGHT,
  };
}

export function noncePublicKey(nonce: number): PublicKeyWithSchema {
  const buffer = new ArrayBuffer(Ed25519PublicKey.SIZE);
  const textEncoder = new TextEncoder();
  textEncoder.encodeInto(NONCE_PK_PREFIX, new Uint8Array(buffer, 0, NONCE_PREFIX_MAX_SIZE));
  const nonceView = new DataView(buffer, NONCE_PREFIX_MAX_SIZE, 4);
  nonceView.setUint32(0, nonce, true);
  const pk = new Ed25519PublicKey(new Uint8Array(buffer));
  return {
    publicKey: pk,
    schema: getSchemaFromPublicKey(pk),
  };
}

export function getSchemaFromPublicKey(pk: PublicKey) {
  const flag = pk.flag() as keyof typeof SIGNATURE_FLAG_TO_SCHEME;
  if (!SIGNATURE_FLAG_TO_SCHEME[flag]) {
    throw new Error('Invalid public key');
  }
  return SIGNATURE_FLAG_TO_SCHEME[flag];
}