feat(hadis): implement is_topic architectural separation for categories and topics

- Add is_topic boolean field to HadisCategory model with indexing
- Enforce validation rules in clean():
  * Topics cannot have children and must define a source_type
  * Structural categories cannot contain hadiths and have source_type=None
  * Parents cannot be topics
  * Hadiths can only be attached to topics (is_topic=True)
- Update admin serializers and views to support is_topic filtering and mapping
- Expose is_topic in public category serializers (SimpleCategory, HadisCategorySelectSerializer, CategorySerializer)
- Include migration 0051_add_category_is_topic

apps/hadis/migrations/0051_add_category_is_topic.py

@@ -0,0 +1,34 @@
+# Generated by Django 4.2.30 on 2026-10-15 09:29
+
+from django.db import migrations, models
+
+
+def populate_is_topic(apps, schema_editor):
+    HadisCategory = apps.get_model('hadis', 'HadisCategory')
+    # All categories that have children -> is_topic=False, source_type=None
+    parent_ids = list(HadisCategory.objects.filter(children__isnull=False).values_list('id', flat=True).distinct())
+    HadisCategory.objects.filter(id__in=parent_ids).update(is_topic=False, source_type=None)
+
+    # All leaf categories (no children) -> is_topic=True
+    HadisCategory.objects.exclude(id__in=parent_ids).update(is_topic=True)
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('hadis', '0050_hadis_categories'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='hadiscategory',
+            name='is_topic',
+            field=models.BooleanField(db_index=True, default=False, verbose_name='Is Topic'),
+        ),
+        migrations.AlterField(
+            model_name='hadiscategory',
+            name='source_type',
+            field=models.CharField(blank=True, choices=[('quran', 'Quran'), ('hadith', 'Hadith'), ('history', 'History'), ('fatwa', 'Fatwa'), ('quote', 'Quote')], max_length=10, null=True, verbose_name='Source Type'),
+        ),
+        migrations.RunPython(populate_is_topic, reverse_code=migrations.RunPython.noop),
+    ]

apps/hadis/models/category.py

@@ -74,7 +74,18 @@ class HadisCategory(LowercaseSlugMixin, MPTTModel):
 
     parent = TreeForeignKey('self', on_delete=models.CASCADE, null=True, blank=True, related_name='children')
     sect = models.ForeignKey(HadisSect, on_delete=models.PROTECT, verbose_name=_('Sect'), null=False, blank=False)
-    source_type = models.CharField(max_length=10, choices=SourceType.choices, verbose_name=_('Source Type'))
+    source_type = models.CharField(
+        max_length=10,
+        choices=SourceType.choices,
+        verbose_name=_('Source Type'),
+        null=True,
+        blank=True
+    )
+    is_topic = models.BooleanField(
+        default=False,
+        db_index=True,
+        verbose_name=_('Is Topic')
+    )
     title = models.JSONField(default = list  , verbose_name=_('Title'))
     description = models.JSONField(default = list  , blank=True, verbose_name=_('Description'))
     order = models.IntegerField(default=0, verbose_name=_('order'))
@@ -87,13 +98,18 @@ class HadisCategory(LowercaseSlugMixin, MPTTModel):
 
     def clean(self):
         super().clean()
-        if self.parent and self.sect_id != self.parent.sect_id:
+        if self.parent:
+            if getattr(self.parent, 'is_topic', False):
+                raise ValidationError(
+                    _('Cannot set parent to a topic. Parent must be a structural category.')
+                )
+            if self.sect_id != self.parent.sect_id:
                 raise ValidationError(
                     _('Child category must have the same sect_type as its parent. '
                       f'Parent sect: {self.parent.sect.sect_type}, '
                       f'Your sect: {self.sect.sect_type}')
                 )
-        parent_has_hadis = self.parent and (
+            parent_has_hadis = (
                 self.parent.hadis_set.exists() or 
                 (hasattr(self.parent, 'hadis_items') and self.parent.hadis_items.exists())
             )
@@ -101,10 +117,28 @@ class HadisCategory(LowercaseSlugMixin, MPTTModel):
                 raise ValidationError(
                     _('Cannot set parent to a category that already contains hadiths/content items.')
                 )
-        has_hadis = self.hadis_set.exists() or (hasattr(self, 'hadis_items') and self.hadis_items.exists())
-        if self.pk and has_hadis and self.children.exists():
+
+        if self.is_topic:
+            if not self.source_type:
+                raise ValidationError(
+                    {'source_type': _('A topic must have a source type.')}
+                )
+            if self.pk and self.children.exists():
                 raise ValidationError(
-                _('A category cannot have both hadiths and subcategories.')
+                    _('A topic cannot have subcategories.')
+                )
+        else:
+            # Structural category: clear source_type if set
+            if self.source_type:
+                self.source_type = None
+
+            has_hadis = self.pk and (
+                self.hadis_set.exists() or 
+                (hasattr(self, 'hadis_items') and self.hadis_items.exists())
+            )
+            if has_hadis:
+                raise ValidationError(
+                    _('A structural category cannot have hadiths/content items attached. Only topics can contain hadiths.')
                 )
 
     slug_source_field = 'title'
@@ -122,14 +156,9 @@ class HadisCategory(LowercaseSlugMixin, MPTTModel):
     def share_link(self):
         if not self.slug:
             return None
-        has_children = getattr(self, "annotated_has_children", None)
-        if has_children is None:
-            if self.pk:
-                has_children = self.children.exists()
-            else:
-                has_children = False
+        if self.is_topic:
+            return f"{settings.DOVODI_DOMAIN}/arguments/category/{self.slug}"
 
-        if has_children:
         sect_type = "shia"
         if self.sect_id:
             try:
@@ -144,8 +173,6 @@ class HadisCategory(LowercaseSlugMixin, MPTTModel):
                 sect_type = "shia"
         return f"{settings.DOVODI_DOMAIN}/arguments/categories/{sect_type}/{self.slug}"
 
-        return f"{settings.DOVODI_DOMAIN}/arguments/category/{self.slug}"
-
     @property
     def xmind_share_link(self):
         if self.slug:

apps/hadis/models/hadis.py

@@ -199,12 +199,21 @@ class Hadis(LowercaseSlugMixin, models.Model):
 
     def clean(self):
         super().clean()
-        if self.category and self.category.children.exists():
+        if self.category:
+            if not getattr(self.category, 'is_topic', False):
+                raise ValidationError(
+                    _('Cannot assign hadith to a structural category. Only topics can contain hadiths.')
+                )
+            if self.category.children.exists():
                 raise ValidationError(
                     _('Cannot assign hadith to a category that has subcategories. Only leaf categories can contain hadiths.')
                 )
         if self.pk:
             for cat in self.categories.all():
+                if not getattr(cat, 'is_topic', False):
+                    raise ValidationError(
+                        _('Cannot assign hadith to a structural category. Only topics can contain hadiths.')
+                    )
                 if cat.children.exists():
                     raise ValidationError(
                         _('Cannot assign hadith to a category that has subcategories. Only leaf categories can contain hadiths.')

apps/hadis/serializers/category.py

@@ -176,7 +176,7 @@ class SimpleCategory(serializers.ModelSerializer):
 
     class Meta:
         model = HadisCategory 
-        fields = ['id', 'title', 'slug', 'source_type', 'sect_type', 'description', 'ancestors']
+        fields = ['id', 'title', 'slug', 'is_topic', 'source_type', 'sect_type', 'description', 'ancestors']
 
     def get_ancestors(self, obj):
         if not obj:
@@ -189,9 +189,10 @@ class SimpleCategory(serializers.ModelSerializer):
                 "id": a.id,
                 "title": get_localized_text(a.title, request=request) or a.slug,
                 "slug": a.slug,
-                "source_type": a.source_type,
+                "is_topic": getattr(a, "is_topic", False),
+                "source_type": a.source_type if getattr(a, "is_topic", False) else None,
                 "sect_type": a.sect.sect_type if a.sect else None,
-                "has_hadis": False,
+                "has_hadis": getattr(a, "is_topic", False),
             })
         return result
 
@@ -237,8 +238,8 @@ class HadisCategorySelectSerializer(serializers.ModelSerializer):
 
     class Meta:
         model = HadisCategory
-        fields = ['id', 'title', 'source_type','slug', 'sect_id',
-         'sect_type','description','children_count','has_hadis','hadis_count', 'has_parent', 'share_link', 'xmind_share_link']
+        fields = ['id', 'title', 'is_topic', 'source_type', 'slug', 'sect_id',
+         'sect_type', 'description', 'children_count', 'has_hadis', 'hadis_count', 'has_parent', 'share_link', 'xmind_share_link']
 
     def get_has_parent(self, obj):
         return obj.parent_id is not None
@@ -283,7 +284,7 @@ class HadisCategorySelectSourceSerializer(serializers.ModelSerializer):
 
     class Meta:
         model = HadisCategory
-        fields = ['id', 'title', 'source_type','slug', 'sect_id',
+        fields = ['id', 'title', 'is_topic', 'source_type','slug', 'sect_id',
          'sect_type','description','children_count','has_hadis','hadis_count', 'has_parent', 'share_link', 'xmind_share_link']
 
     def get_has_parent(self, obj):
@@ -323,7 +324,7 @@ class CategorySerializer(serializers.ModelSerializer):
 
     class Meta:
         model = HadisCategory
-        fields = ['id', 'title', 'sect_id', 'sect_type','source_type',
+        fields = ['id', 'title', 'sect_id', 'sect_type', 'is_topic', 'source_type',
         'description','slug',
          'children_count','has_hadis','hadis_count', 'has_parent', 'share_link', 'xmind_share_link']
 

apps/hadis/serializers/serializers_admin.py

@@ -2,6 +2,7 @@ from rest_framework import serializers
 from django.core.files.uploadedfile import SimpleUploadedFile
 from django.utils.translation import gettext_lazy as _
 from django.db.models import Exists, OuterRef, Q
+from django.core.exceptions import ValidationError as DjangoValidationError
 
 from utils.image_compression import maybe_compress_uploaded_file
 from utils import absolute_https_url
@@ -96,6 +97,7 @@ class AdminHadisCategorySerializer(serializers.ModelSerializer):
                 "id": a.id,
                 "title": a.title,
                 "slug": a.slug,
+                "is_topic": a.is_topic,
                 "source_type": a.source_type,
                 "sect_type": a.sect.sect_type if a.sect else None,
                 "order": a.order,
@@ -112,6 +114,7 @@ class AdminHadisCategorySerializer(serializers.ModelSerializer):
             "parent",
             "title",
             "slug",
+            "is_topic",
             "source_type",
             "order",
             "sect",
@@ -1654,6 +1657,7 @@ class AdminHadisCategoryArchiveSerializer(serializers.ModelSerializer):
             "parent_detail",
             "sect",
             "sect_detail",
+            "is_topic",
             "source_type",
             "title",
             "description",
@@ -1670,8 +1674,24 @@ class AdminHadisCategoryArchiveSerializer(serializers.ModelSerializer):
         read_only_fields = ["id", "share_link", "xmind_share_link"]
         extra_kwargs = {
             "description": {"required": False},
+            "source_type": {"required": False, "allow_null": True, "allow_blank": True},
         }
 
+    def validate(self, attrs):
+        is_topic = attrs.get('is_topic', getattr(self.instance, 'is_topic', False))
+        source_type = attrs.get('source_type', getattr(self.instance, 'source_type', None))
+        if is_topic:
+            if not source_type:
+                raise serializers.ValidationError({"source_type": _("A topic must have a source type.")})
+        else:
+            attrs['source_type'] = None
+
+        parent = attrs.get('parent', getattr(self.instance, 'parent', None))
+        if parent and getattr(parent, 'is_topic', False):
+            raise serializers.ValidationError({"parent": _("Cannot set parent to a topic. Parent must be a category.")})
+
+        return super().validate(attrs)
+
     def to_internal_value(self, data):
         import json
         data = safe_copy_data(data)
@@ -1684,9 +1704,23 @@ class AdminHadisCategoryArchiveSerializer(serializers.ModelSerializer):
                     pass
         return super().to_internal_value(data)
 
+    @staticmethod
+    def _raise_drf_validation_error(exc):
+        if hasattr(exc, "message_dict"):
+            detail = {
+                ("non_field_errors" if key == "__all__" else key): value
+                for key, value in exc.message_dict.items()
+            }
+        else:
+            detail = {"non_field_errors": exc.messages}
+        raise serializers.ValidationError(detail)
+
     def create(self, validated_data):
         validated_data.pop("remove_xmind_file", False)
+        try:
             return super().create(validated_data)
+        except DjangoValidationError as exc:
+            self._raise_drf_validation_error(exc)
 
 
 class AdminHadisCategoryArchiveDetailSerializer(AdminHadisCategoryArchiveSerializer):
@@ -1705,6 +1739,7 @@ class AdminHadisCategoryArchiveDetailSerializer(AdminHadisCategoryArchiveSeriali
                 "id": a.id,
                 "title": a.title,
                 "slug": a.slug,
+                "is_topic": a.is_topic,
                 "source_type": a.source_type,
                 "sect_type": a.sect.sect_type if a.sect else None,
                 "order": a.order,
@@ -1746,6 +1781,7 @@ class AdminHadisCategoryArchiveDetailSerializer(AdminHadisCategoryArchiveSeriali
                 "title": c.title,
                 "slug": c.slug,
                 "order": c.order,
+                "is_topic": c.is_topic,
                 "source_type": c.source_type,
                 "has_children": bool(c.annotated_has_children),
                 "has_hadith": bool(c.annotated_has_hadith),
@@ -1799,7 +1835,10 @@ class AdminHadisCategoryArchiveDetailSerializer(AdminHadisCategoryArchiveSeriali
         if remove_xmind_file and instance.xmind_file:
             instance.xmind_file.delete(save=False)
             instance.xmind_file = None
+        try:
             return super().update(instance, validated_data)
+        except DjangoValidationError as exc:
+            self._raise_drf_validation_error(exc)
 
 class AdminTransmitterReliabilitySerializer(serializers.ModelSerializer):
     class Meta:

apps/hadis/views/category.py

@@ -235,7 +235,8 @@ class HadisCategoryTreeView(ListAPIView):
             'all_titles': all_titles,
             'search_text': search_blob,
             'slug': category.slug,
-            'source_type': category.source_type,
+            'is_topic': category.is_topic,
+            'source_type': category.source_type if category.is_topic else None,
             'sect_id': category.sect_id,
             'sect_type': category.sect.sect_type,
             'hadis_count': category.direct_hadis_count,

apps/hadis/views_admin.py

@@ -115,9 +115,9 @@ class AdminHadisCategoryViewSet(ReadOnlyModelViewSet):
         is_topic = self.request.query_params.get("is_topic")
         if is_topic is not None and is_topic != "all":
             if str(is_topic).lower() in ["true", "1"]:
-                queryset = queryset.filter(annotated_has_children=False)
+                queryset = queryset.filter(is_topic=True)
             elif str(is_topic).lower() in ["false", "0"]:
-                queryset = queryset.filter(annotated_has_children=True)
+                queryset = queryset.filter(is_topic=False)
         return queryset.order_by("order", "id")
 
 
@@ -197,9 +197,9 @@ class DovodiHadisCategoryViewSet(ModelViewSet):
         is_topic = self.request.query_params.get("is_topic")
         if is_topic is not None and is_topic != "all":
             if str(is_topic).lower() in ["true", "1"]:
-                queryset = queryset.filter(annotated_has_children=False)
+                queryset = queryset.filter(is_topic=True)
             elif str(is_topic).lower() in ["false", "0"]:
-                queryset = queryset.filter(annotated_has_children=True)
+                queryset = queryset.filter(is_topic=False)
         return queryset.order_by("-id")