import * as util from 'util'
import * as readline from 'readline'
import { webcrypto } from 'node:crypto'
import { stdin as input, stdout as output } from 'process'

const { subtle } = webcrypto

const rl = readline.createInterface({ input, output })

rl.input.on('keypress', (c) => {
  if (c.charCodeAt() === 127) {
    const len = rl.line.length
    readline.moveCursor(rl.output, -len, 0)
    readline.clearLine(rl.output, 1)
    return
  }
  readline.moveCursor(rl.output, -1, 0)
  readline.clearLine(rl.output, 1)
})

const question = util.promisify(rl.question).bind(rl)

;(async () => {
  try {
    let password = await question('password for decrypt: ')
    password = password.trim()
    let data = await question('encrypted base64 data: ')
    data = data.trim()

    const encoder = new TextEncoder()

    const keyMaterial = await subtle.importKey(
      'raw',
      encoder.encode(password),
      'PBKDF2',
      false,
      ['deriveKey', 'deriveBits']
    )

    const salt = encoder.encode(password)

    const bits = await subtle.deriveBits({
      name: 'PBKDF2',
      hash: 'SHA-512',
      salt,
      iterations: 1000
    }, keyMaterial, 256)

    const key = await subtle.deriveKey(
      {
        name: 'PBKDF2',
        hash: 'SHA-512',
        salt,
        iterations: 100,
      },
      keyMaterial,
      {
        name: 'AES-GCM',
        length: 256,
      },
      true,
      ['encrypt', 'decrypt']
    )

    const ciphertext = Buffer.from(data, 'base64')

    const decrypted = await subtle.decrypt(
      {
        name: 'AES-GCM',
        iv: bits
      },
      key,
      ciphertext
    )

    const decoder = new TextDecoder()

    console.log('original: ', decoder.decode(decrypted))
  } catch (err) {
    console.error('rejected', err)
  }
  process.exit(1)
})()