derive.ts

import HDKey from 'hdkey'

import { publicToAddress, toChecksumAddress } from '@ethereumjs/util'

export enum Derivation {
  live = 'live',
  legacy = 'legacy',
  standard = 'standard',
  testnet = 'testnet'
}

export function deriveHDAccounts(publicKey: string, chainCode: string, cb: Callback<string[]>) {
  try {
    const hdk = new HDKey()
    hdk.publicKey = Buffer.from(publicKey, 'hex')
    hdk.chainCode = Buffer.from(chainCode, 'hex')
    const derive = (index: number) => {
      const derivedKey = hdk.derive(`m/${index}`)
      const address = Buffer.from(publicToAddress(derivedKey.publicKey, true)).toString('hex')
      return toChecksumAddress(`0x${address}`)
    }
    const accounts = []
    for (let i = 0; i < 100; i++) {
      accounts[i] = derive(i)
    }

    cb(null, accounts)
  } catch (e) {
    cb(e as Error, undefined)
  }
}

const derivationPaths: { [key: string]: string } = {
  [Derivation.legacy.valueOf()]: "44'/60'/0'/<index>",
  [Derivation.standard.valueOf()]: "44'/60'/0'/0/<index>",
  [Derivation.testnet.valueOf()]: "44'/1'/0'/0/<index>",
  [Derivation.live.valueOf()]: "44'/60'/<index>'/0/0"
}

export function getDerivationPath(derivation: Derivation, index = -1) {
  const path = derivationPaths[derivation.valueOf()]

  return path.replace('<index>', (index > -1 ? index : '').toString())
}