Fix amends for empty documentations

aleksis/apps/alsijil/model_extensions.py

-from django.db.models import FilteredRelation, Q, QuerySet
+from django.db.models import FilteredRelation, Q, QuerySet, Value
 from django.db.models.aggregates import Count, Sum
 from django.utils.translation import gettext as _
 
@@ -34,36 +34,58 @@ Person.add_permission("register_absence_person", _("Can register an absence for
 
 
 def annotate_person_statistics(
-    persons: QuerySet[Person], participations_filter: Q, personal_notes_filter: Q
+    persons: QuerySet[Person],
+    participations_filter: Q,
+    personal_notes_filter: Q,
+    *,
+    ignore_filters: bool = False,
 ) -> QuerySet[Person]:
     """Annotate a queryset of persons with class register statistics."""
-    persons = persons.annotate(
-        filtered_participation_statuses=FilteredRelation(
-            "participations",
-            condition=(participations_filter),
-        ),
-        filtered_personal_notes=FilteredRelation(
-            "new_personal_notes",
-            condition=(personal_notes_filter),
-        ),
-    ).annotate(
-        participation_count=Count(
-            "filtered_participation_statuses",
-            filter=Q(filtered_participation_statuses__absence_reason__isnull=True),
-            distinct=True,
-        ),
-        absence_count=Count(
-            "filtered_participation_statuses",
-            filter=Q(filtered_participation_statuses__absence_reason__count_as_absent=True),
-            distinct=True,
-        ),
-        tardiness_sum=Sum("filtered_participation_statuses__tardiness", distinct=True),
-        tardiness_count=Count(
-            "filtered_participation_statuses",
-            filter=Q(filtered_participation_statuses__tardiness__gt=0),
-            distinct=True,
-        ),
-    )
+
+    if ignore_filters:
+        persons = persons.annotate(
+            absence_count=Value(0),
+            filtered_participation_statuses=FilteredRelation(
+                "participations",
+                condition=Q(pk=None),
+            ),
+            filtered_personal_notes=FilteredRelation(
+                "new_personal_notes",
+                condition=Q(pk=None),
+            ),
+            participation_count=Value(0),
+            tardiness_count=Value(0),
+            tardiness_sum=Value(0),
+        )
+    else:
+        persons = persons.annotate(
+            filtered_participation_statuses=FilteredRelation(
+                "participations",
+                condition=(participations_filter),
+            ),
+            filtered_personal_notes=FilteredRelation(
+                "new_personal_notes",
+                condition=(personal_notes_filter),
+            ),
+        ).annotate(
+            participation_count=Count(
+                "filtered_participation_statuses",
+                filter=Q(filtered_participation_statuses__absence_reason__isnull=True),
+                distinct=True,
+            ),
+            absence_count=Count(
+                "filtered_participation_statuses",
+                filter=Q(filtered_participation_statuses__absence_reason__count_as_absent=True),
+                distinct=True,
+            ),
+            tardiness_sum=Sum("filtered_participation_statuses__tardiness", distinct=True),
+            tardiness_count=Count(
+                "filtered_participation_statuses",
+                filter=Q(filtered_participation_statuses__tardiness__gt=0),
+                distinct=True,
+            ),
+        )
+
     persons = persons.order_by("last_name", "first_name")
 
     for absence_reason in AbsenceReason.objects.all():
@@ -116,4 +138,5 @@ def annotate_person_statistics_for_school_term(
         persons,
         Q(participations__related_documentation__in=docs),
         Q(new_personal_notes__documentation__in=docs),
+        ignore_filters=len(docs) == 0,
     )