import {
  createCipheriv,
  createHmac, scryptSync,
} from 'crypto'
import { validateAuthKeys } from '../../helpers'

import { Response, Body } from './types'

export async function ServerUtils_AuthCreate({
  authKeys,
  loginResponse,
  apiKey,
}: Body): Promise<Response> {
  try {
    validateAuthKeys(authKeys)
    // Get the current authKey and create a new key from it that is 32 bits
    const secret = authKeys.current!
    const key = scryptSync(secret, apiKey, 32)

    // Create a hash with the new key to
    const hash = createHmac('sha256', key).digest('hex')
    const jsonToBeEncrypted = {
      ...loginResponse,
      wappiAuthKey: hash,
    }
    const loginBody = JSON.stringify(jsonToBeEncrypted)

    const iv = scryptSync(secret, apiKey, 16) // generate the same ciphertext everytime
    const algorithm = 'aes-256-cbc' // algorithm to use
    const cipher = createCipheriv(algorithm, key, iv)
    const encryptedKey = cipher.update(loginBody, 'utf8', 'hex') + cipher.final('hex') // encrypted text

    return {
      auth: encryptedKey,
    }
  } catch (err) {
    return new Promise((resolve) => {
      const response = {
        error: 'Fatal error in ServerUtils_AuthCreate. Investigate.',
        errorMessage: err.message,
        auth: '',
      }
      // eslint-disable-next-line no-promise-executor-return
      return resolve(response)
    })
  }
}