fix(new-submissions): always check for existing sub

src/Handler/Submission.hs

@@ -314,16 +314,21 @@ submissionHelper tid ssh csh shn mcid = do
     csheet@(Entity shid Sheet{..})  <- fetchSheet tid ssh csh shn
     maySubmit  <- (== Authorized) <$> evalAccessDB actionUrl True
     isLecturer <- (== Authorized) <$> evalAccessDB (CSheetR tid ssh csh shn SSubsR) True
-    case (msmid, sheetGrouping) of
-      (Nothing, Arbitrary maxBuddies) -> do
+
     submissions <- E.select . E.from $ \(submission `E.InnerJoin` submissionUser) -> do
       E.on (submission E.^. SubmissionId E.==. submissionUser E.^. SubmissionUserSubmission)
       E.where_ $ submissionUser E.^. SubmissionUserUser   E.==. E.val uid
            E.&&. submission     E.^. SubmissionSheet    E.==. E.val shid
       return $ submission E.^. SubmissionId
-        -- logDebugS "Submission.DUPLICATENEW" (tshow submissions)
-        case submissions of
-          []    -> do
+    case (msmid, submissions) of
+      (Nothing, E.Value smid : _) -> do
+        cID <- encrypt smid
+        addMessageI Info MsgSubmissionAlreadyExists
+        redirect $ CSubmissionR tid ssh csh shn cID SubShowR
+      _other -> return ()
+  
+    case (msmid, sheetGrouping) of
+      (Nothing, Arbitrary maxBuddies) -> do
         -- fetch buddies from previous submission in this course
         buddies <- E.select . E.from $ \(submissionUser `E.InnerJoin` user) -> do
           E.on (submissionUser E.^. SubmissionUserUser E.==. user E.^. UserId)
@@ -351,10 +356,6 @@ submissionHelper tid ssh csh shn mcid = do
                , isLecturer
                , not isLecturer
                )
-          (E.Value smid:_) -> do
-            cID <- encrypt smid
-            addMessageI Info MsgSubmissionAlreadyExists
-            redirect $ CSubmissionR tid ssh csh shn cID SubShowR
       (Nothing, _) -> return (csheet, Set.empty, [], maySubmit, isLecturer, not isLecturer) -- TODO: Return registered group members
       (Just smid, _) -> do
         void $ submissionMatchesSheet tid ssh csh shn (fromJust mcid)