refactor(Learnocaml_teacher_tab): Move critical code apart in update_exercise_assignments

Namely => Learnocaml_data.Exercise.Status.update_exercise_assignments.

Author: erikmd

src/app/learnocaml_teacher_tab.ml

@@ -1032,73 +1032,23 @@ let rec teacher_tab token _select _params () =
          current_assignment)
   in
   let set_assignment ?assg ?students ?exos ?default id =
+    (* - get the currently saved assignment *)
     let (assg0, students0, exos0, default0) = Hashtbl.find assignments_tbl id in
+    (* - update the assignment fields if related arg <> None *)
     let dft x0 = function Some x -> x | None -> x0 in
     let start, stop = dft assg0 assg in
     let students = dft students0 students in
     let exos = dft exos0 exos in
     let default = dft default0 default in
+    (* - update the assignment *)
     Hashtbl.replace assignments_tbl id
       ((start, stop), students, exos, default);
     (match Manip.by_id (assg_line_id id) with
      | Some l -> Manip.replaceSelf l (assignment_line id)
      | None -> failwith "Assignment line not found");
-    let status = ES.(Assigned {start; stop}) in
+    (* - update (!status_changes : ES.t SMap.t) (initially empty) *)
     let exercise_status_changes =
-      SSet.fold (fun ex_id acc ->
-          let st = get_status ex_id in
-          let assg = st.ES.assignments in
-          let old_default = assg.ES.default in
-          let new_default =
-            if default then status
-            else if default0 then ES.Closed
-            else old_default
-          in
-          let add tk st tmap =
-            if st = new_default then tmap
-            else Token.Map.add tk st tmap
-          in
-          let token_map =
-            Token.Map.fold (fun tk _ acc ->
-                if Token.Set.mem tk students then
-                  if default then acc
-                  else Token.Map.add tk status acc
-                else if Token.Set.mem tk students0 then
-                  if default then Token.Map.add tk ES.Closed acc
-                  else Token.Map.remove tk acc
-                else add tk (ES.get_status tk assg) acc)
-              !students_map Token.Map.empty
-          in
-          SMap.add ex_id
-            ES.{st with assignments = {
-                token_map;
-                default = new_default;
-              }}
-            acc)
-        exos
-        !status_changes
-    in
-    let exercise_status_changes =
-      SSet.fold (fun ex_id acc ->
-          let st = get_status ex_id in
-          let assg = st.ES.assignments in
-          let dft_status =
-            if default0 then ES.Closed else ES.default_assignment assg
-          in
-          let token_map =
-            Token.Set.fold Token.Map.remove students0 assg.ES.token_map
-          in
-          let token_map =
-            Token.Map.filter (fun _ a -> a <> dft_status) token_map
-          in
-          SMap.add ex_id
-            ES.{st with assignments = {
-                token_map;
-                default = dft_status
-              }}
-            acc)
-        (SSet.diff exos0 exos)
-        exercise_status_changes
+      ES.update_exercise_assignments get_status (students0, exos0, default0) (students, exos, default) (start, stop) !students_map !status_changes
     in
     status_changes := exercise_status_changes;
     fill_exercises_pane ();

src/state/learnocaml_data.ml

@@ -626,7 +626,64 @@ module Exercise = struct
       | GloballyOpen -> a
       | GloballyInconsistent -> fix_open_close ~close:false a
 
-    (* Note/Erik: we may also want to implement set_assigned_globally *)
+    let update_exercise_assignments (get_status_t : string -> t) (students0, exos0, default0) (students, exos, default) (start, stop) students_map status_map =
+      let status = Assigned {start; stop} in
+      (* - walk accross the new list of exos *)
+      let status_map =
+        SSet.fold (fun ex_id acc ->
+            let st = get_status_t ex_id in
+            let assg = st.assignments in
+            let old_default = assg.default in
+            let new_default =
+              if default then status
+              else if default0 then Closed
+              else old_default
+            in
+            let add tk st tmap =
+              if st = new_default then tmap
+              else Token.Map.add tk st tmap
+            in
+            let token_map =
+              Token.Map.fold (fun tk _ acc ->
+                  if Token.Set.mem tk students then
+                    if default then acc
+                    else Token.Map.add tk status acc
+                  else if Token.Set.mem tk students0 then
+                    if default then Token.Map.add tk Closed acc
+                    else Token.Map.remove tk acc
+                  else add tk (get_status tk assg) acc)
+                students_map Token.Map.empty
+            in
+            SMap.add ex_id
+              {st with assignments = {
+                  token_map;
+                  default = new_default;
+              }}
+              acc)
+          exos
+          status_map
+      in
+      (* - walk accross the list of removed exos *)
+      SSet.fold (fun ex_id acc ->
+          let st = get_status_t ex_id in
+          let assg = st.assignments in
+          let dft_status =
+            if default0 then Closed else default_assignment assg
+          in
+          let token_map =
+            Token.Set.fold Token.Map.remove students0 assg.token_map
+          in
+          let token_map =
+            Token.Map.filter (fun _ a -> a <> dft_status) token_map
+          in
+          SMap.add ex_id
+            {st with assignments = {
+                token_map;
+                default = dft_status
+            }}
+            acc)
+        (SSet.diff exos0 exos)
+        status_map
 
     let is_open_assignment token a =
       match get_status token a with

src/state/learnocaml_data.mli

@@ -251,6 +251,18 @@ module Exercise: sig
     (** Call [check_open_close] then (if need be) [fix_open_close] *)
     val check_and_fix_open_close: assignments -> assignments
 
+    (** Update [status_map: Exercise.Status.t SMap.t] if an assignment changes:
+        [update_exercise_assignments g (s0,e0,d0) (s,e,d) (t0,t1) m status_map]
+        turns [(stu0,exo0,dft0)] to [(s,e,d) + Assigned{t0;t1}] in [status_map]
+        from [g = get_status_t: string -> t] (status of exo) and [m = stud_map] *)
+    val update_exercise_assignments: (string -> t) ->
+      Token.Set.t * SSet.t * bool ->
+      Token.Set.t * SSet.t * bool ->
+      float * float ->
+      Student.t Token.Map.t ->
+      t SMap.t ->
+      t SMap.t
+
     val is_open_assignment:
       Token.t -> assignments -> [> `Open | `Closed | `Deadline of float]