best deal price fields added to product serialzier

backend/product/models.py

@@ -211,6 +211,9 @@ class ProductModel(models.Model):
             self.slug = slugify(self.name, allow_unicode=True)
         super().save(*args, **kwargs)
         
+    def get_best_deal_variant(self):
+        return self.variants.order_by("price", "-discount").first()
+
     class Meta:
         verbose_name = 'محصول'
         verbose_name_plural = 'محصولات'

backend/product/serializers.py

@@ -136,7 +136,9 @@ class DynamicProductSerializer(serializers.ModelSerializer):
     is_new = serializers.SerializerMethodField()
     related_products = serializers.SerializerMethodField()
     added_to_favorites = serializers.SerializerMethodField()
-
+    best_deal_price_before_discount = serializers.SerializerMethodField()
+    best_deal_price_after_discount = serializers.SerializerMethodField()
+    best_deal_discount = serializers.SerializerMethodField()
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         view_type = self.context.get('view_type', 'all')
@@ -152,11 +154,30 @@ class DynamicProductSerializer(serializers.ModelSerializer):
         model = ProductModel
         fields = "__all__"
         view_type = {
-            'list': ['id', 'name', 'rating', 'slug', 'category', 'variants', 'colors', 'image'],
+            'list': ['id', 'name', 'rating', 'slug', 'category', 'variants', 'colors', 'image', 'best_deal_price_before_discount', 'best_deal_price_after_discount', 'best_deal_discount', ],
-            'slider': ['id', 'name', 'rating', 'slug', 'category', 'variants', 'colors', 'image'],
+            'slider': ['id', 'name', 'rating', 'slug', 'category', 'variants', 'colors', 'image', 'best_deal_price_before_discount', 'best_deal_price_after_discount', 'best_deal_discount', ],
             'instance': ['id', 'name', 'description', 'rating',  'slug', 'meta_description', 'meta_keywords', 'meta_rating', 'category', 'related_products', 'in_pack_items', 'variants', 'colors', 'added_to_favorites', 'image'],
             'chat': ['id', 'name', 'description', 'variants', 'image']
         }
+    def get_best_deal_price_before_discount(self, obj):
+        best_deal = obj.get_best_deal_variant()
+        if best_deal:
+            return f'{best_deal.price:,.0f} تومانءءء'
+        return 0
+    
+    def get_best_deal_price_after_discount(self, obj):
+        best_deal = obj.get_best_deal_variant()
+        if best_deal:
+            price_after_discount = best_deal.price_after_discount
+            return f'{price_after_discount:,.0f} تومانءءء'
+        return 0
+    
+    def get_best_deal_discount(self, obj):
+        best_deal = obj.get_best_deal_variant()
+        if best_deal:
+            return best_deal.discount
+        return 0
+
 
     def get_added_to_favorites(self, obj):
         from account.models import UserFavorites