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

module Jobs.Handler.SendNotification.Qualification
  ( dispatchNotificationQualificationExpiry
  , 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

-- import qualified Database.Esqueleto.Experimental as E
-- import qualified Database.Esqueleto.Utils as E


dispatchNotificationQualificationExpiry :: QualificationId -> Day -> UserId -> Handler ()
dispatchNotificationQualificationExpiry nQualification _nExpiry jRecipient = userMailT jRecipient $ do
  (recipient@User{..}, Qualification{..}, Entity _ QualificationUser{..}) <- liftHandler . runDB $ (,,)
    <$> getJust jRecipient
    <*> getJust nQualification
    <*> getJustBy (UniqueQualificationUser nQualification jRecipient)
  
  encRecipient :: CryptoUUIDUser <- liftHandler $ encrypt jRecipient
  let entRecipient = Entity jRecipient recipient
      qname = CI.original qualificationName
  expiryDate <- formatTimeUser SelFormatDate qualificationUserValidUntil $ 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")


-- NOTE: qualificationRenewal expects that LmsUser already exists for recipient
dispatchNotificationQualificationRenewal :: QualificationId -> UserId -> Handler ()
dispatchNotificationQualificationRenewal nQualification jRecipient = do
  (recipient@User{..}, Qualification{..}, Entity _ QualificationUser{..}, Entity _ 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

  $logDebugS "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"
      prepAddress upa = userDisplayName : (upa & html2textlines) -- TODO: use supervisor's address 
      lmsIdent = lmsUserIdent & getLmsIdent
      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"           ("[https://drive.fraport.de](https://drive.fraport.de/?login=" <> lmsIdent <> ")")
                  ]
  pdfRenewal pdfMeta >>= \case
    Left err -> do
      let msg = "Notify " <> tshow encRecipient <> " PDF generation failed with error: " <> err
      $logErrorS "LMS" msg
      error $ unpack msg

    Right pdf | userPrefersLetter recipient -> do
        let printSender  = Nothing 
        runDB (sendLetter printJobName pdf (Just jRecipient, printSender) Nothing (Just nQualification)) >>= \case        
          Left err -> do
            let msg = "Notify " <> tshow encRecipient <> "  PDF printing to send letter failed with error: " <> err
            $logErrorS "LMS" msg
            error $ unpack msg
          Right (msg,_) 
            | null msg  -> return ()
            | otherwise -> $logWarnS "LMS" $ "PDF printing to send letter with lpr returned ExitSucces and the following message: " <> msg

    Right pdf -> userMailT jRecipient $ do 
        -- userPrefersLetter is false if both userEmail and userPostAddress are null
        when (Text.null (CI.original userEmail)) $ $logErrorS "LMS" ("Notify " <> tshow encRecipient <> " failed: no email nor address for user known!")

        replaceMailHeader "Auto-Submitted" $ Just "auto-generated"
        setSubjectI $ MsgMailSubjectQualificationRenewal qname
              
        let fileName = printJobName <> "_" <> abbrvName recipient <> ".pdf"

        encryptPDF (fromMaybe "tomatenmarmelade" userPinPassword) pdf >>= \case -- TODO
          Left err -> do
            let msg = "Notify " <> tshow encRecipient <> " PDF encryption failed with error: " <> err
            $logErrorS "LMS" msg
            
          Right pdffile -> do
            addPart (File { fileTitle = Text.unpack fileName
                          , fileModified = now
                          , fileContent = Just $ yield $ LBS.toStrict pdffile
                          } :: PureFile)

        editNotifications <- mkEditNotifications jRecipient
        addHtmlMarkdownAlternatives $(ihamletFile "templates/mail/qualificationRenewal.hamlet")