Add free-text search filter for Examination in CaseFilter to improve searchability

atlas/filters.py

@@ -106,6 +106,9 @@ class CaseFilter(django_filters.FilterSet):
         queryset=lambda request: __import__('generic.models', fromlist=['Examination']).Examination.objects.filter(atlas_series_examination__isnull=False).distinct(),
         label='Examination',
     )
+    # Free-text search to help find the correct examination when there are
+    # many similarly-named Series/Examination entries.
+    examination_text = django_filters.CharFilter(method='filter_examination_text', label='Examination (text)')
     differential_case = django_filters.ModelMultipleChoiceFilter(
         label="Differential",
         field_name="differentialcase__condition",
@@ -140,6 +143,36 @@ class CaseFilter(django_filters.FilterSet):
         )
         pass
 
+    def filter_examination_text(self, queryset, name, value):
+        """Filter Cases by a text search on related Examination records.
+
+        Matches against the Examination string representation and any
+        common identifying fields (name/code). Uses a case-insensitive
+        contains lookup and filters Cases which have a Series linked to
+        a matching Examination.
+        """
+        if not value:
+            return queryset
+
+        from generic.models import Examination
+
+        # Only attempt to match PK when the provided value looks like an integer
+        try:
+            pk_val = int(value)
+        except Exception:
+            pk_val = None
+
+        if pk_val is not None:
+            matches = Examination.objects.filter(
+                Q(examination__icontains=value) | Q(pk=pk_val)
+            ).distinct()
+        else:
+            matches = Examination.objects.filter(
+                Q(examination__icontains=value)
+            ).distinct()
+
+        return queryset.filter(series__examination__in=matches).distinct()
+
 
 class SeriesFilter(django_filters.FilterSet):
     case = django_filters.ModelMultipleChoiceFilter(