From cc205596ae55826dcefe51ebaef3227ad72bb3d8 Mon Sep 17 00:00:00 2001
From: Gregor Kleen <kleen@cip.ifi.lmu.de>
Date: Sun, 13 Oct 2019 22:20:23 +0200
Subject: [PATCH] feat(allocations): allow additional notifications

---
 src/Jobs/Crontab.hs                   |  3 ++-
 src/Jobs/Handler/QueueNotification.hs | 17 +++++++++++++++--
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/src/Jobs/Crontab.hs b/src/Jobs/Crontab.hs
index a852dcdc7..210fa4cc7 100644
--- a/src/Jobs/Crontab.hs
+++ b/src/Jobs/Crontab.hs
@@ -338,12 +338,13 @@ determineCrontab = execWriterT $ do
         _other
           -> return ()
       doneSince <- lift $ allocationDone nAllocation
+
       whenIsJust doneSince $ \doneSince' ->
         tell $ HashMap.singleton
           (JobCtlQueue $ JobQueueNotification NotificationAllocationResults{..})
           Cron
             { cronInitial   = CronTimestamp . utcToLocalTimeTZ appTZ $ addUTCTime appNotificationCollateDelay doneSince'
-            , cronRepeat    = CronRepeatNever
+            , cronRepeat    = CronRepeatOnChange
             , cronRateLimit = appNotificationRateLimit
             , cronNotAfter  = Left appNotificationExpiration
             }
diff --git a/src/Jobs/Handler/QueueNotification.hs b/src/Jobs/Handler/QueueNotification.hs
index 8812d2f48..b38c0dcb2 100644
--- a/src/Jobs/Handler/QueueNotification.hs
+++ b/src/Jobs/Handler/QueueNotification.hs
@@ -198,7 +198,8 @@ determineNotificationCandidates NotificationExamOfficeExamResultsChanged{..} =
       E.where_ $ examResult E.^. ExamResultId `E.in_` E.valList (Set.toList nExamResults)
       E.where_ $ examOfficeExamResultAuth (user E.^. UserId) examResult
     return user
-determineNotificationCandidates NotificationAllocationResults{..} =
+determineNotificationCandidates notif@NotificationAllocationResults{..} = do
+  lastExec <- fmap (fmap $ cronLastExecTime . entityVal) . getBy . UniqueCronLastExec . toJSON $ JobQueueNotification notif
   E.select . E.from $ \user -> do
     let isStudent = E.exists . E.from $ \application ->
           E.where_ $ application E.^. CourseApplicationAllocation E.==. E.just (E.val nAllocation)
@@ -207,7 +208,19 @@ determineNotificationCandidates NotificationAllocationResults{..} =
           E.on $ lecturer E.^. LecturerCourse E.==. allocationCourse E.^. AllocationCourseCourse
            E.&&. allocationCourse E.^. AllocationCourseAllocation E.==. E.val nAllocation
            E.&&. lecturer E.^. LecturerUser E.==. user E.^. UserId
-    E.where_ $ isStudent E.||. isLecturer
+
+        wasAllocated t = E.exists . E.from $ \participant ->
+          E.where_ $ participant E.^. CourseParticipantUser E.==. user E.^. UserId
+               E.&&. participant E.^. CourseParticipantAllocated E.==. E.just (E.val nAllocation)
+               E.&&. participant E.^. CourseParticipantRegistration E.>. E.val t
+        hasAllocations t = E.exists . E.from $ \(lecturer `E.InnerJoin` participant) -> do
+          E.on $ lecturer E.^. LecturerUser E.==. user E.^. UserId
+           E.&&. lecturer E.^. LecturerCourse E.==. participant E.^. CourseParticipantCourse
+          E.where_ $ participant E.^. CourseParticipantAllocated E.==. E.just (E.val nAllocation)
+               E.&&. participant E.^. CourseParticipantRegistration E.>. E.val t
+    case lastExec of
+      Nothing -> E.where_ $ isStudent E.||. isLecturer
+      Just t  -> E.where_ $ wasAllocated t E.||. hasAllocations t
 
     return user
 determineNotificationCandidates NotificationCourseRegistered{..} =