module Handler.Exam.List
  ( getCExamListR
  ) where

import Import

import Handler.Utils
  
import qualified Data.Map as Map

import qualified Database.Esqueleto as E


getCExamListR :: TermId -> SchoolId -> CourseShorthand -> Handler Html
getCExamListR tid ssh csh = do
  Entity cid Course{..} <- runDB . getBy404 $ TermSchoolCourseShort tid ssh csh
  now <- liftIO getCurrentTime
  mayCreate <- hasWriteAccessTo $ CourseR tid ssh csh CExamNewR

  let
    examDBTable = DBTable{..}
      where
        dbtSQLQuery exam = do
          E.where_ $ exam E.^. ExamCourse E.==. E.val cid
          return exam
        dbtRowKey = (E.^. ExamId)
        dbtProj x@DBRow{ dbrOutput = Entity _ Exam{..} } = do
          guardM . hasReadAccessTo $ CExamR tid ssh csh examName EShowR
          return x
        dbtColonnade = dbColonnade . mconcat $ catMaybes
          [ Just . sortable (Just "name") (i18nCell MsgExamName) $ \DBRow{ dbrOutput = Entity _ Exam{..} } -> anchorCell (CExamR tid ssh csh examName EShowR) examName
          , (<$ guard mayCreate) . sortable (Just "visible") (i18nCell MsgExamVisibleFrom) $ \DBRow { dbrOutput = Entity _ Exam{..} } -> maybe mempty (dateTimeCellVisible now) examVisibleFrom
          , Just . sortable (Just "register-from") (i18nCell MsgExamRegisterFrom) $ \DBRow { dbrOutput = Entity _ Exam{..} } -> maybe mempty dateTimeCell examRegisterFrom
          , Just . sortable (Just "register-to") (i18nCell MsgExamRegisterTo) $ \DBRow { dbrOutput = Entity _ Exam{..} } -> maybe mempty dateTimeCell examRegisterTo
          , Just . sortable (Just "time") (i18nCell MsgExamTime) $ \DBRow{ dbrOutput = Entity _ Exam{..} } -> maybe mempty (cell . flip (formatTimeRangeW SelFormatDateTime) examEnd) examStart
          ]
        dbtSorting = Map.fromList
          [ ("name", SortColumn $ \exam -> exam E.^. ExamName )
          , ("time", SortColumn $ \exam -> exam E.^. ExamStart )
          , ("register-from", SortColumn $ \exam -> exam E.^. ExamRegisterFrom )
          , ("register-to", SortColumn $ \exam -> exam E.^. ExamRegisterTo )
          , ("visible", SortColumn $ \exam -> exam E.^. ExamVisibleFrom )
          ]
        dbtFilter = Map.empty
        dbtFilterUI = const mempty
        dbtStyle = def
        dbtParams = def
        dbtIdent :: Text
        dbtIdent = "exams"
        dbtCsvEncode = noCsvEncode
        dbtCsvDecode = Nothing

    examDBTableValidator = def
      & defaultSorting [SortAscBy "time"]
  ((), examTable) <- runDB $ dbTable examDBTableValidator examDBTable

  siteLayoutMsg (prependCourseTitle tid ssh csh MsgExamsHeading) $ do
    setTitleI $ prependCourseTitle tid ssh csh MsgExamsHeading
    $(widgetFile "exam-list")