content: {-
   Copyright 2022-23, Juspay India Pvt Ltd
  
   This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License
  
   as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program
  
   is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  
   or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more details. You should have received a copy of
  
   the GNU Affero General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.
  -}
  module Tools.Utils where
  
  import Crypto.OTP (OTP, defaultTOTPParams, totp)
  import Crypto.Random (getRandomBytes)
  import Data.ByteString.Base32 as Base32
  import qualified Data.Text.Encoding as T
  import qualified Data.Time.Clock.POSIX as DT
  import qualified Domain.Types.Merchant as DMerchant
  import Kernel.Prelude
  import Kernel.Types.Id
  
  genTOTP :: Text -> IO OTP
  genTOTP secretKey = do
    time <- DT.getPOSIXTime
    let secretKeyBytes = either (error . show) identity (Base32.decodeBase32 (T.encodeUtf8 secretKey))
    pure (totp defaultTOTPParams secretKeyBytes (floor time))
  
  generateSecretKey :: IO Text
  generateSecretKey = do
    randomBytes <- getRandomBytes 20
    pure $ encodeBase32 randomBytes
  
  generateAuthenticatorURI :: Text -> Text -> ShortId DMerchant.Merchant -> Text
  generateAuthenticatorURI secretKey user issuer = "otpauth://totp/" <> issuer.getShortId <> "?secret=" <> secretKey <> "&user=" <> user
  