-- SPDX-FileCopyrightText: 2022-23 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 Jobs.Handler.SendNotification.Utils

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


dispatchNotificationQualificationExpiry :: QualificationId -> Day -> UserId -> Handler ()
dispatchNotificationQualificationExpiry nQualification dExpiry jRecipient = userMailT 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

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


dispatchNotificationQualificationExpired :: QualificationId -> UserId -> Handler ()
dispatchNotificationQualificationExpired nQualification jRecipient = do  
  encRecipient :: CryptoUUIDUser <- encrypt jRecipient
  encRecShort <- encrypt jRecipient
  dbRes <- runDB $ (,,)
    <$> get jRecipient
    <*> get nQualification
    <*> getBy (UniqueQualificationUser nQualification jRecipient)    

  case dbRes of 
    ( Just User{..}, Just Qualification{..}, Just (Entity quId QualificationUser{..})) -> do
      now <- liftIO getCurrentTime
      qub_entry <- entityVal <<$>> runDB (selectRelevantBlock now quId)
      let block = filterMaybe (not . qualificationUserBlockUnblock) qub_entry 
      urender <- getUrlRender
      let expDay  = maybe qualificationUserValidUntil (min qualificationUserValidUntil . utctDay . qualificationUserBlockFrom) block
          qname   = CI.original qualificationName
          qshort  = CI.original qualificationShorthand
          letter  = LetterExpireQualificationF 
            { leqfHolderCFN  = encRecShort
            , leqfHolderID   = jRecipient
            , leqfHolderDN   = userDisplayName
            , leqfHolderSN   = userSurname
            , leqfExpiry     = Just expDay
            , leqfId         = nQualification
            , leqfName       = qname
            , leqfShort      = qshort
            , leqfSchool     = qualificationSchool
            , leqfUrl        = pure . urender $ ForProfileDataR encRecipient
            }
      if expDay > utctDay qualificationUserLastNotified 
        then do
          notifyOk <- sendEmailOrLetter jRecipient letter
          if notifyOk
            then do               
              runDB $ update quId [QualificationUserLastNotified =. now]
              $logInfoS  "LMS" $ "Notified " <> tshow encRecipient <> " about expired qualification " <> qname
            else 
              $logErrorS "LMS" $ "Failed to notify " <> tshow encRecipient <> " about expired qualification " <> qname
        else  $logErrorS "LMS" $ "Suppressed repeated notification " <> tshow encRecipient <> " about expired qualification " <> qname
    _ ->  $logErrorS "LMS" $ "Failed to notify " <> tshow encRecipient <> " about expired qualification " <> tshow nQualification


-- NOTE: Renewal expects that LmsUser already exists for recipient
dispatchNotificationQualificationRenewal :: QualificationId -> UserId -> Handler ()
dispatchNotificationQualificationRenewal nQualification jRecipient = do
  encRecipient :: CryptoUUIDUser <- encrypt jRecipient
  query <- runDB $ (,,,) 
    <$> get jRecipient
    <*> get nQualification
    <*> getBy (UniqueQualificationUser    nQualification jRecipient)
    <*> getBy (UniqueLmsQualificationUser nQualification jRecipient)
  case query of 
    (Just User{userDisplayName, userSurname}, Just Qualification{..}, Just (Entity _ QualificationUser{..}), Just(Entity luid LmsUser{..})) -> do
      let qname = CI.original qualificationName
          letter = LetterRenewQualificationF
            { lmsLogin     = lmsUserIdent
            , lmsPin       = lmsUserPin
            , qualHolderID = jRecipient
            , qualHolderDN = userDisplayName 
            , qualHolderSN = userSurname
            , qualExpiry   = qualificationUserValidUntil
            , qualId       = nQualification            
            , qualName     = qname
            , qualShort    = CI.original qualificationShorthand                                
            , qualSchool   = qualificationSchool            
            , qualDuration = qualificationValidDuration
            }
      $logInfoS "LMS" $ "Notify " <> tshow encRecipient <> " for renewal of qualification " <> qname
      notifyOk <- sendEmailOrLetter jRecipient letter
      when notifyOk $ do 
        now <- liftIO getCurrentTime
        runDB $ update luid [ LmsUserNotified =. Just now]
    (_, Nothing, _, _) -> $logErrorS "LMS" $ "Notify " <> tshow encRecipient <> " for renewal failed: Qualification " <> tshow nQualification <> " does not exist!"
    (Nothing, _, _, _) -> $logErrorS "LMS" $ "Notify " <> tshow encRecipient <> " for renewal failed: User does not exist!"
    (_, _, Nothing, _) -> $logErrorS "LMS" $ "Notify " <> tshow encRecipient <> " for renewal failed: QualificationUser does not exist, i.e. user does not have this qualification!"
    (_, _, _, Nothing) -> $logWarnS  "LMS" $ "Notify " <> tshow encRecipient <> " for renewal failed: LmsUser does not exist!"