#51 fix: detectar cambios de categorias al sincronizar productos

Issue #51: discriminacion y administracion de categorias de productos.

- _need_update compara las categorias (external_id) local vs Tryton
- _describe_changes reporta categorias agregadas (+Nombre) y removidas (-Nombre)
- Actualiza test que asumia asignacion de categorias sin marcar update

tienda_ilusion/don_confiao/services/tryton/products.py

@@ -214,8 +214,50 @@ class ProductTrytonService:
                 changes.append(
                     f"Unidad: {product.measuring_unit} → {unit_name}"
                 )
+        category_changes = self._describe_category_changes(
+            product, tryton_product
+        )
+        if category_changes:
+            changes.append(category_changes)
         return ", ".join(changes)
 
+    def _describe_category_changes(self, product, tryton_product):
+        """Describe los cambios de categorías entre el producto local y Tryton"""
+        tryton_ids = set(
+            str(category_id)
+            for category_id in self._extract_category_ids(tryton_product)
+        )
+        local = {
+            external_id: name
+            for external_id, name in product.categories.values_list(
+                "external_id", "name"
+            )
+            if external_id
+        }
+        local_ids = set(local)
+
+        added = sorted(tryton_ids - local_ids)
+        removed = sorted(local_ids - tryton_ids)
+        if not added and not removed:
+            return ""
+
+        parts = []
+        if added:
+            names = {}
+            for external_id in added:
+                category = (
+                    ProductCategory.objects.filter(
+                        external_id=external_id
+                    )
+                    .values_list("name", flat=True)
+                    .first()
+                )
+                names[external_id] = category or external_id
+            parts.append(", ".join(f"+{names[e]}" for e in added))
+        if removed:
+            parts.append(", ".join(f"-{local[e]}" for e in removed))
+        return f"Categoría: {', '.join(parts)}"
+
     @staticmethod
     def _format_price(value):
         """Formatea un precio sin ceros decimales innecesarios"""
@@ -269,6 +311,17 @@ class ProductTrytonService:
         unit = tryton_product.get("default_uom.")
         if not product.measuring_unit == unit.get("rec_name"):
             return True
+        tryton_category_ids = set(
+            str(category_id)
+            for category_id in self._extract_category_ids(tryton_product)
+        )
+        local_category_ids = set(
+            product.categories.exclude(
+                external_id__isnull=True
+            ).values_list("external_id", flat=True)
+        )
+        if tryton_category_ids != local_category_ids:
+            return True
         return False
 
     def _create_product(self, tryton_product):

tienda_ilusion/don_confiao/tests/test_products_from_tryton.py

@@ -661,7 +661,7 @@ class TestProductsFromTryton(TestCase, LoginMixin):
 
     @patch("sabatron_tryton_rpc_client.client.Client.call")
     @patch("sabatron_tryton_rpc_client.client.Client.connect")
-    def test_import_assigns_categories_to_untouched_products(
+    def test_import_assigns_categories_marks_product_as_updated(
         self, mock_connect, mock_call
     ):
         mock_connect.return_value = None
@@ -724,12 +724,20 @@ class TestProductsFromTryton(TestCase, LoginMixin):
         self.assertEqual(response.status_code, 200)
 
         content = json.loads(response.content.decode("utf-8"))
+        self.assertEqual(content["untouched_products"], [])
         self.assertEqual(
-            content["untouched_products"], [{"id": 2, "name": "Papa"}]
+            content["updated_products"],
+            [
+                {
+                    "id": 2,
+                    "name": "Papa",
+                    "detail": "Categoría: +Tubérculos",
+                }
+            ],
         )
 
-        untouched_product = Product.objects.get(id=2)
+        updated_product = Product.objects.get(id=2)
-        categories = untouched_product.categories.all()
+        categories = updated_product.categories.all()
         self.assertEqual(len(categories), 1)
         self.assertEqual(categories[0].name, "Tubérculos")
         self.assertEqual(categories[0].external_id, "9")
@@ -744,3 +752,104 @@ class TestProductsFromTryton(TestCase, LoginMixin):
                 }
             ],
         )
+
+    @patch("sabatron_tryton_rpc_client.client.Client.call")
+    @patch("sabatron_tryton_rpc_client.client.Client.connect")
+    def test_category_change_marks_product_as_updated(
+        self, mock_connect, mock_call
+    ):
+        mock_connect.return_value = None
+        local_abarrotes = ProductCategory.objects.create(
+            name="Abarrotes", external_id="5"
+        )
+        self.product2.categories.add(local_abarrotes)
+
+        def fake_call(*args, **kwargs):
+            product_search = "model.product.product.search"
+            search_args = [
+                [["salable", "=", True]],
+                0,
+                1000,
+                [["rec_name", "ASC"], ["id", None]],
+                {"company": 1},
+            ]
+            if args == (product_search, search_args):
+                return [192]
+
+            product_read = "model.product.product.read"
+            product_args = (
+                [192],
+                [
+                    "id",
+                    "name",
+                    "default_uom.id",
+                    "default_uom.rec_name",
+                    "list_price",
+                    "template.categories",
+                ],
+                {"company": 1},
+            )
+            if args == (product_read, product_args):
+                return [
+                    {
+                        "id": 192,
+                        "list_price": Decimal("4500"),
+                        "name": "Papa",
+                        "default_uom.": {"id": 2, "rec_name": "Kilogram"},
+                        "template.": {"id": 999, "categories": [8]},
+                    },
+                ]
+
+            category_read = "model.product.category.read"
+            category_args = (
+                [8],
+                ["id", "name"],
+                {"company": 1},
+            )
+            if args == (category_read, category_args):
+                return [
+                    {"id": 8, "name": "Bebidas"},
+                ]
+
+            raise Exception(
+                f"Sorry, args non expected on  this test: {args}"
+            )
+
+        mock_call.side_effect = fake_call
+
+        url = "/don_confiao/api/importar_productos_de_tryton"
+        response = self.client.post(url)
+        self.assertEqual(response.status_code, 200)
+
+        content = json.loads(response.content.decode("utf-8"))
+        self.assertEqual(content["untouched_products"], [])
+        self.assertEqual(content["failed_products"], [])
+        self.assertEqual(
+            content["updated_products"],
+            [
+                {
+                    "id": self.product2.pk,
+                    "name": "Papa",
+                    "detail": "Categoría: +Bebidas, -Abarrotes",
+                }
+            ],
+        )
+        self.assertEqual(
+            content["created_categories"],
+            [
+                {
+                    "id": ProductCategory.objects.get(
+                        external_id="8"
+                    ).pk,
+                    "name": "Bebidas",
+                    "external_id": "8",
+                }
+            ],
+        )
+
+        refreshed_product = Product.objects.get(pk=self.product2.pk)
+        categories = list(refreshed_product.categories.all())
+        self.assertEqual(
+            [(c.external_id, c.name) for c in categories],
+            [("8", "Bebidas")],
+        )