From c2bbe1b8ec529ee7dccccd7213b008465d3bd776 Mon Sep 17 00:00:00 2001
From: Parsa Nazer <parsa.nazerrr@gmail.com>
Date: Mon, 18 May 2026 14:42:15 +0330
Subject: [PATCH] comment rate added to serilizer and user detail added too

---
 backend/product/serializers.py | 20 ++++++++++++++++++++
 backend/product/views.py       | 24 +++++++++++++++++++++++-
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/backend/product/serializers.py b/backend/product/serializers.py
index d1e5d65..adf2ece 100644
--- a/backend/product/serializers.py
+++ b/backend/product/serializers.py
@@ -3,6 +3,7 @@ from rest_framework import serializers
 from django.utils import timezone
 from datetime import timedelta
 from django.contrib.auth.models import AnonymousUser
+from account.models import User
 
 
 class DetailSerializer(serializers.ModelSerializer):
@@ -323,12 +324,31 @@ class DynamicProductSerializer(serializers.ModelSerializer):
         return serializer.data
 
 
+class UserCommentSerializer(serializers.ModelSerializer):
+    """Lightweight user serializer for comment author info"""
+    class Meta:
+        model = User
+        fields = ['id', 'first_name', 'last_name', 'profile_photo', 'phone']
+
+
 class CommentSerializer(serializers.ModelSerializer):
+    user = UserCommentSerializer(read_only=True)
+    user_rating = serializers.SerializerMethodField()
+
     class Meta:
         model = CommentModel
         exclude = ('review_status', )
         read_only_fields = ('review_status', 'product', 'user')
 
+    def get_user_rating(self, obj):
+        """
+        Get user's rating for this product using cached data to avoid N+1 queries.
+        The cache is provided by the CommentView.get() method.
+        """
+        user_ratings_cache = self.context.get('user_ratings_cache', {})
+        # O(1) lookup in cache instead of database query
+        return user_ratings_cache.get(obj.user_id)
+
 
 class BotProductSerializer(serializers.ModelSerializer):
     class Meta:
diff --git a/backend/product/views.py b/backend/product/views.py
index e40327a..3bfe627 100644
--- a/backend/product/views.py
+++ b/backend/product/views.py
@@ -590,8 +590,30 @@ class CommentView(APIView):
         ).select_related('user')
         paginator = self.pagination_class()
         paginated_comments = paginator.paginate_queryset(comments, request)
+
+        # OPTIMIZATION: Fetch all user ratings in a single query
+        # Get user IDs from paginated comments to only fetch ratings for displayed comments
+        user_ids = [comment.user_id for comment in paginated_comments]
+
+        # Single query to get all ratings for these users on this product
+        user_ratings = ProductRating.objects.filter(
+            product=product,
+            user_id__in=user_ids
+        ).values_list('user_id', 'rating')
+
+        # Build cache dictionary for O(1) lookups in serializer
+        user_ratings_cache = {user_id: rating for user_id, rating in user_ratings}
+
+        # Pass cache to serializer context to avoid N queries
         comments_ser = self.serializer_class(
-            instance=paginated_comments, many=True)
+            instance=paginated_comments,
+            many=True,
+            context={
+                'request': request,
+                'user_ratings_cache': user_ratings_cache,
+                'product': product
+            }
+        )
         return paginator.get_paginated_response(comments_ser.data)
 
     def post(self, request, slug):