import {
  createDecipheriv,
  createHmac, scryptSync,
} from 'crypto'

import { AuthValidateResponse } from './types'

export const decryptHash = ({
  secret,
  apiKey,
  auth,
  key,
}: {
  secret: string,
  apiKey: string,
  auth: string,
  key: Buffer,
}) => {
  try {
    const iv = scryptSync(secret, apiKey, 16) // generate the same ciphertext every time
    const algorithm = 'aes-256-cbc' // algorithm to use

    const decipher = createDecipheriv(algorithm, key, iv)
    const decrypted = decipher.update(auth, 'hex', 'utf8') + decipher.final('utf8')
    return {
      success: true,
      ...JSON.parse(decrypted),
    }
  } catch (error) {
    return {
      success: false,
    }
  }
}

export const compareHashes = (authHash: string, key: Buffer) => {
  const newHash = createHmac('sha256', key).digest('hex')
  if (authHash === newHash) return true
  return false
}

export const errorMessage = (response: AuthValidateResponse) => {
  response.error = 'Not Authorised, Log In'
  response.access = false
  return response
}