-- SPDX-FileCopyrightText: 2022 Steffen Jost <jost@tcs.ifi.lmu.de>
--
-- SPDX-License-Identifier: AGPL-3.0-or-later

{-# OPTIONS_GHC -fno-warn-unused-do-bind #-} -- ihamletFile discards do results

module Jobs.Handler.SendNotification.Qualification
  ( dispatchNotificationQualificationExpiry
  , dispatchNotificationQualificationExpired
  , dispatchNotificationQualificationRenewal
  ) where

import Import

import Utils.Print
import Handler.Utils
import Handler.Utils.Users
import Jobs.Handler.SendNotification.Utils

import qualified Data.ByteString.Lazy as LBS

import qualified Data.Text as Text

-- import Handler.Info (FAQItem(..))
import qualified Data.CaseInsensitive as CI
import Text.Hamlet


dispatchNotificationQualificationExpiry :: QualificationId -> Day -> UserId -> Maybe UserId -> Handler ()
dispatchNotificationQualificationExpiry nQualification dExpiry jRecipient jSupervisor = superMailT jSupervisor jRecipient $ do
  (recipient@User{..}, Qualification{..}) <- liftHandler . runDB $ (,)
    <$> getJust jRecipient
    <*> getJust nQualification    

  encRecipient :: CryptoUUIDUser <- liftHandler $ encrypt jRecipient
  let entRecipient = Entity jRecipient recipient
      qname = CI.original qualificationName
  expiryDate <- formatTimeUser SelFormatDate dExpiry $ Just entRecipient

  $logDebugS "LMS" $ "Notify " <> tshow encRecipient <> " about expiry of qualification " <> qname

  replaceMailHeader "Auto-Submitted" $ Just "auto-generated"
  setSubjectI $ MsgMailSubjectQualificationExpiry qname

  editNotifications <- mkEditNotifications jRecipient

  -- if supervisor: 
  let inner = $(ihamletFile "templates/mail/qualificationExpiry.hamlet")
  --addHtmlMarkdownAlternatives $(ihamletFile "templates/mail/supervisor.hamlet") -- uses ^{inner}
  addHtmlMarkdownAlternatives inner


dispatchNotificationQualificationExpired :: QualificationId -> Day -> UserId -> Maybe UserId -> Handler ()
dispatchNotificationQualificationExpired nQualification dExpired jRecipient jSupervisor = superMailT jSupervisor jRecipient $ do
  (recipient@User{..}, Qualification{..}) <- liftHandler . runDB $ (,)
    <$> getJust jRecipient
    <*> getJust nQualification

  encRecipient :: CryptoUUIDUser <- liftHandler $ encrypt jRecipient
  let entRecipient = Entity jRecipient recipient
      qname = CI.original qualificationName
  expiryDate <- formatTimeUser SelFormatDate dExpired $ Just entRecipient

  $logDebugS "LMS" $ "Notify " <> tshow encRecipient <> " about expired qualification " <> qname

  replaceMailHeader "Auto-Submitted" $ Just "auto-generated"
  setSubjectI $ MsgMailSubjectQualificationExpired qname

  editNotifications <- mkEditNotifications jRecipient

  addHtmlMarkdownAlternatives $(ihamletFile "templates/mail/qualificationExpired.hamlet")


-- NOTE: qualificationRenewal expects that LmsUser already exists for recipient
dispatchNotificationQualificationRenewal :: QualificationId -> UserId -> Maybe UserId -> Handler ()
dispatchNotificationQualificationRenewal nQualification jRecipient jSupervisor = do
  (recipient@User{..}, Qualification{..}, Entity _ QualificationUser{..}, Entity luid LmsUser{..}) <- runDB $ (,,,)
    <$> getJust jRecipient
    <*> getJust nQualification
    <*> getJustBy (UniqueQualificationUser    nQualification jRecipient)
    <*> getJustBy (UniqueLmsQualificationUser nQualification jRecipient)

  encRecipient :: CryptoUUIDUser <- encrypt jRecipient
  let entRecipient = Entity jRecipient recipient
      qname = CI.original qualificationName

  $logInfoS "LMS" $ "Notify " <> tshow encRecipient <> " for renewal of qualification " <> qname

  now <- liftIO getCurrentTime
  letterDate <- formatTimeUser SelFormatDate now                         $ Just entRecipient
  expiryDate <- formatTimeUser SelFormatDate qualificationUserValidUntil $ Just entRecipient

  let printJobName = "RenewalPin"
      fileName  = printJobName <> "_" <> abbrvName recipient <> ".pdf"
      lmsIdent  = lmsUserIdent & getLmsIdent
      lmsUrl    = "https://drive.fraport.de"
      lmsLogin  = lmsUrl <> "/?login=" <> lmsIdent
      prepAddress upa = userDisplayName : (upa & html2textlines) -- TODO: use supervisor's address, once implemented
      pdfMeta   = mkMeta
                  [ toMeta "date"           letterDate
                  , toMeta "lang"          (selectDeEn userLanguages)    -- select either German or English only, see Utils.Lang
                  , toMeta "login"          lmsIdent
                  , toMeta "pin"            lmsUserPin
                  , toMeta "recipient"      userDisplayName
                  , mbMeta "address"       (prepAddress <$> userPostAddress)
                  , toMeta "expiry"         expiryDate
                  , mbMeta "validduration" (show <$> qualificationValidDuration)
                  , toMeta "url-text"       lmsUrl
                  , toMeta "url"            lmsLogin
                  ]
      emailRenewal attachment
        | Text.null (CI.original userEmail) = do          -- if neither email nor postal address is known, we must abort!
            let msg = "Notify " <> tshow encRecipient <> " failed: no email nor address for user known!"
            $logErrorS "LMS" msg
            return False
        | otherwise = do
            superMailT jSupervisor jRecipient $ do
              replaceMailHeader "Auto-Submitted" $ Just "auto-generated"
              setSubjectI $ MsgMailSubjectQualificationRenewal qname
              whenIsJust attachment $ \afile ->
                addPart (File { fileTitle = Text.unpack fileName
                              , fileModified = now
                              , fileContent = Just $ yield $ LBS.toStrict afile
                              } :: PureFile)
              editNotifications <- mkEditNotifications jRecipient
              addHtmlMarkdownAlternatives $(ihamletFile "templates/mail/qualificationRenewal.hamlet")
            return True

  notifyOk <- pdfRenewal pdfMeta >>= \case
    Right pdf | userPrefersLetter recipient ->          -- userPrefersLetter is false if both userEmail and userPostAddress are null
      let printSender  = Nothing
      in runDB (sendLetter printJobName pdf (Just jRecipient, printSender) Nothing (Just nQualification) (Just lmsUserIdent)) >>= \case
        Left err -> do
          let msg = "Notify " <> tshow encRecipient <> ": PDF printing to send letter failed with error " <> cropText err
          $logErrorS "LMS" msg
          return False
        Right (msg,_)
          | null msg  -> return True
          | otherwise -> do
              $logWarnS "LMS" $ "PDF printing to send letter with lpr returned ExitSucces and the following message: " <> msg
              return True

    Right pdf -> do
      attch <- case userPinPassword of
        Nothing   -> return $ Just pdf                  -- attach unencrypted, since there is no password set
        Just passwd -> encryptPDF passwd pdf >>= \case
          Right encPdf -> return $ Just encPdf          -- attach encrypted
          Left err -> do                                -- send email without attachment, so that the user is at least notified about the expiry
            let msg = "Notify " <> tshow encRecipient <> " PDF encryption failed with error: " <> cropText err
            $logErrorS "LMS" msg
            return Nothing
      emailRenewal attch

    Left err -> do
      let msg = "Notify " <> tshow encRecipient <> " PDF generation failed with error: " <> cropText err
      $logErrorS "LMS" msg
      emailRenewal Nothing

  when notifyOk $ runDB $ update luid [ LmsUserNotified =. Just now]