feat: Add signal handler for synchronizing Incoming edits with StockBatch

## Changes

### 1. Fixed missing signal handler for Incoming edit (inventory/signals.py)
- Added new signal handler `update_stock_batch_on_incoming_edit()` that:
  - Triggers when Incoming is edited (created=False)
  - Synchronizes StockBatch with new quantity and cost_price values
  - Automatically triggers cost price recalculation for the product
  - Updates Stock (inventory balance) for the warehouse
  - Includes proper logging and error handling

### 2. Created IncomingModelForm for editing individual incoming items (inventory/forms.py)
- New ModelForm: `IncomingModelForm` that:
  - Inherits from forms.ModelForm (accepts 'instance' parameter required by UpdateView)
  - Allows editing: product, quantity, cost_price, notes
  - Includes validation for positive quantity and non-negative cost_price
  - Filters only active products

### 3. Updated IncomingUpdateView (inventory/views/incoming.py)
- Changed form_class from IncomingForm to IncomingModelForm
- Updated imports to include IncomingModelForm
- Removed obsolete comments from form_valid method

## Architecture

When editing an Incoming item:
1. User submits form with new quantity/cost_price
2. form.save() triggers post_save signal (created=False)
3. update_stock_batch_on_incoming_edit() synchronizes StockBatch
4. StockBatch.save() triggers update_product_cost_on_batch_change()
5. Product.cost_price is recalculated with weighted average

## Problem Solved

Previously, editing an Incoming item would NOT:
- Update the related StockBatch
- Recalculate product cost_price
- Update warehouse inventory balance
- Maintain data consistency between Incoming and StockBatch

Now all these operations happen automatically through the signal chain.

🤖 Generated with Claude Code

Co-Authored-By: Claude <noreply@anthropic.com>

myproject/inventory/forms.py

@@ -13,12 +13,31 @@ from products.models import Product
 class WarehouseForm(forms.ModelForm):
     class Meta:
         model = Warehouse
-        fields = ['name', 'description', 'is_active', 'is_default']
+        fields = [
+            'name',
+            'description',
+            'street',
+            'building_number',
+            'phone',
+            'email',
+            'is_active',
+            'is_default',
+            'is_pickup_point'
+        ]
         widgets = {
-            'name': forms.TextInput(attrs={'class': 'form-control'}),
+            'name': forms.TextInput(attrs={'class': 'form-control', 'placeholder': 'Название склада'}),
-            'description': forms.Textarea(attrs={'class': 'form-control', 'rows': 4}),
+            'description': forms.Textarea(attrs={'class': 'form-control', 'rows': 3, 'placeholder': 'Описание'}),
+            'street': forms.TextInput(attrs={'class': 'form-control', 'placeholder': 'Улица'}),
+            'building_number': forms.TextInput(attrs={'class': 'form-control', 'placeholder': 'Номер дома'}),
+            'phone': forms.TextInput(attrs={'class': 'form-control', 'placeholder': '+375 (29) 123-45-67'}),
+            'email': forms.EmailInput(attrs={'class': 'form-control', 'placeholder': 'email@example.com'}),
             'is_active': forms.CheckboxInput(attrs={'class': 'form-check-input'}),
             'is_default': forms.CheckboxInput(attrs={'class': 'form-check-input'}),
+            'is_pickup_point': forms.CheckboxInput(attrs={'class': 'form-check-input'}),
+        }
+        help_texts = {
+            'is_default': 'Автоматически выбирается при создании новых документов',
+            'is_pickup_point': 'Можно ли выбрать этот склад как точку самовывоза заказа',
         }
 
 
@@ -308,6 +327,41 @@ class IncomingForm(forms.Form):
         return document_number
 
 
+class IncomingModelForm(forms.ModelForm):
+    """
+    ModelForm для редактирования отдельного товара в поступлении (Incoming).
+    Используется в IncomingUpdateView для редактирования существующих товаров.
+    """
+    class Meta:
+        model = Incoming
+        fields = ['product', 'quantity', 'cost_price', 'notes']
+        widgets = {
+            'product': forms.Select(attrs={'class': 'form-control'}),
+            'quantity': forms.NumberInput(attrs={'class': 'form-control', 'step': '0.001'}),
+            'cost_price': forms.NumberInput(attrs={'class': 'form-control', 'step': '0.01'}),
+            'notes': forms.Textarea(attrs={'class': 'form-control', 'rows': 3}),
+        }
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        # Фильтруем только активные товары
+        self.fields['product'].queryset = Product.objects.filter(
+            is_active=True
+        ).order_by('name')
+
+    def clean_quantity(self):
+        quantity = self.cleaned_data.get('quantity')
+        if quantity and quantity <= 0:
+            raise ValidationError('Количество должно быть больше нуля')
+        return quantity
+
+    def clean_cost_price(self):
+        cost_price = self.cleaned_data.get('cost_price')
+        if cost_price and cost_price < 0:
+            raise ValidationError('Цена не может быть отрицательной')
+        return cost_price
+
+
 # ============================================================================
 # TRANSFER FORMS - Перемещение товаров между складами
 # ============================================================================

myproject/inventory/signals.py

@@ -232,6 +232,81 @@ def create_stock_batch_on_incoming(sender, instance, created, **kwargs):
     stock.refresh_from_batches()
 
 
+@receiver(post_save, sender=Incoming)
+def update_stock_batch_on_incoming_edit(sender, instance, created, **kwargs):
+    """
+    Сигнал: При редактировании товара в приходе (Incoming) автоматически
+    обновляется связанная партия товара на складе (StockBatch).
+
+    Это обеспечивает синхронизацию данных между Incoming и StockBatch.
+
+    Архитектура:
+    - Если Incoming редактируется - обновляем StockBatch с новыми значениями
+    - Обновление StockBatch автоматически пересчитывает себестоимость товара (Product.cost_price)
+      через сигнал update_product_cost_on_batch_change()
+
+    Процесс:
+    1. Проверяем, это редактирование (created=False), а не создание
+    2. Получаем связанный StockBatch
+    3. Проверяем, изменились ли quantity или cost_price
+    4. Если да - обновляем StockBatch
+    5. Сохраняем StockBatch (запускает цепь пересчета себестоимости)
+    6. Обновляем остатки на складе (Stock)
+    """
+    if created:
+        return  # Только для редактирования (не для создания)
+
+    # Получаем связанный StockBatch
+    if not instance.stock_batch:
+        return  # Если нет связи со StockBatch - нечего обновлять
+
+    stock_batch = instance.stock_batch
+
+    import logging
+    logger = logging.getLogger(__name__)
+
+    try:
+        # Проверяем, отличаются ли значения в StockBatch от Incoming
+        # Это говорит нам о том, что произошло редактирование
+        needs_update = (
+            stock_batch.quantity != instance.quantity or
+            stock_batch.cost_price != instance.cost_price
+        )
+
+        if not needs_update:
+            return  # Никаких изменений
+
+        # Обновляем StockBatch с новыми значениями из Incoming
+        stock_batch.quantity = instance.quantity
+        stock_batch.cost_price = instance.cost_price
+        stock_batch.save()
+
+        logger.info(
+            f"✓ StockBatch #{stock_batch.id} обновлён при редактировании Incoming: "
+            f"quantity={instance.quantity}, cost_price={instance.cost_price} "
+            f"(товар: {instance.product.sku})"
+        )
+
+        # Обновляем Stock (остатки на складе)
+        warehouse = stock_batch.warehouse
+        stock, _ = Stock.objects.get_or_create(
+            product=instance.product,
+            warehouse=warehouse
+        )
+        stock.refresh_from_batches()
+
+        logger.info(
+            f"✓ Stock обновлён для товара {instance.product.sku} "
+            f"на складе {warehouse.name}"
+        )
+
+    except Exception as e:
+        logger.error(
+            f"Ошибка при обновлении StockBatch при редактировании Incoming #{instance.id}: {e}",
+            exc_info=True
+        )
+
+
 @receiver(post_save, sender=Sale)
 def process_sale_fifo(sender, instance, created, **kwargs):
     """

myproject/inventory/templates/inventory/warehouse/warehouse_form.html

@@ -47,7 +47,7 @@
                 </label>
                 <textarea class="form-control {% if form.description.errors %}is-invalid{% endif %}"
                           id="{{ form.description.id_for_label }}" name="{{ form.description.html_name }}"
-                          rows="4">{{ form.description.value|default:'' }}</textarea>
+                          rows="3">{{ form.description.value|default:'' }}</textarea>
                 {% if form.description.errors %}
                     <div class="invalid-feedback">
                         {% for error in form.description.errors %}
@@ -57,6 +57,72 @@
                 {% endif %}
             </div>
 
+            <h5 class="mt-4 mb-3">Адрес</h5>
+
+            <div class="row">
+                <div class="col-md-8 mb-3">
+                    <label for="{{ form.street.id_for_label }}" class="form-label">
+                        {{ form.street.label }}
+                    </label>
+                    {{ form.street }}
+                    {% if form.street.errors %}
+                        <div class="invalid-feedback d-block">
+                            {% for error in form.street.errors %}
+                                {{ error }}
+                            {% endfor %}
+                        </div>
+                    {% endif %}
+                </div>
+
+                <div class="col-md-4 mb-3">
+                    <label for="{{ form.building_number.id_for_label }}" class="form-label">
+                        {{ form.building_number.label }}
+                    </label>
+                    {{ form.building_number }}
+                    {% if form.building_number.errors %}
+                        <div class="invalid-feedback d-block">
+                            {% for error in form.building_number.errors %}
+                                {{ error }}
+                            {% endfor %}
+                        </div>
+                    {% endif %}
+                </div>
+            </div>
+
+            <h5 class="mt-4 mb-3">Контакты</h5>
+
+            <div class="row">
+                <div class="col-md-6 mb-3">
+                    <label for="{{ form.phone.id_for_label }}" class="form-label">
+                        {{ form.phone.label }}
+                    </label>
+                    {{ form.phone }}
+                    {% if form.phone.errors %}
+                        <div class="invalid-feedback d-block">
+                            {% for error in form.phone.errors %}
+                                {{ error }}
+                            {% endfor %}
+                        </div>
+                    {% endif %}
+                </div>
+
+                <div class="col-md-6 mb-3">
+                    <label for="{{ form.email.id_for_label }}" class="form-label">
+                        {{ form.email.label }}
+                    </label>
+                    {{ form.email }}
+                    {% if form.email.errors %}
+                        <div class="invalid-feedback d-block">
+                            {% for error in form.email.errors %}
+                                {{ error }}
+                            {% endfor %}
+                        </div>
+                    {% endif %}
+                </div>
+            </div>
+
+            <h5 class="mt-4 mb-3">Настройки</h5>
+
             <div class="mb-3">
                 <div class="form-check">
                     <input type="checkbox" class="form-check-input"
@@ -76,7 +142,21 @@
                     <label class="form-check-label" for="{{ form.is_default.id_for_label }}">
                         {{ form.is_default.label }}
                         <small class="text-muted d-block">
-                            Отмечьте, чтобы использовать этот склад по умолчанию при создании новых документов
+                            {{ form.is_default.help_text }}
+                        </small>
+                    </label>
+                </div>
+            </div>
+
+            <div class="mb-3">
+                <div class="form-check">
+                    <input type="checkbox" class="form-check-input"
+                           id="{{ form.is_pickup_point.id_for_label }}" name="{{ form.is_pickup_point.html_name }}"
+                           {% if form.is_pickup_point.value %}checked{% endif %}>
+                    <label class="form-check-label" for="{{ form.is_pickup_point.id_for_label }}">
+                        {{ form.is_pickup_point.label }}
+                        <small class="text-muted d-block">
+                            {{ form.is_pickup_point.help_text }}
                         </small>
                     </label>
                 </div>

myproject/inventory/views/incoming.py

@@ -10,7 +10,7 @@ from django.views.decorators.http import require_http_methods
 from django.utils.decorators import method_decorator
 from django.db import IntegrityError, transaction
 from ..models import Incoming, IncomingBatch, Warehouse
-from ..forms import IncomingForm, IncomingLineForm
+from ..forms import IncomingForm, IncomingLineForm, IncomingModelForm
 from inventory.utils import generate_incoming_document_number
 from products.models import Product
 
@@ -47,13 +47,11 @@ class IncomingUpdateView(LoginRequiredMixin, UpdateView):
     Обработанные приходы редактировать нельзя.
     """
     model = Incoming
-    form_class = IncomingForm
+    form_class = IncomingModelForm
     template_name = 'inventory/incoming/incoming_form.html'
     success_url = reverse_lazy('inventory:incoming-list')
 
     def form_valid(self, form):
-        # При редактировании можем оставить номер пустым - модель генерирует при сохранении
-        # Но это только если объект ещё не имеет номера (новый)
         messages.success(self.request, f'Приход товара обновлён.')
         return super().form_valid(form)