feat: MVP-скелет площадки (Django + MySQL/SQLite, модели по ТЗ §4, базовые страницы)

apps/orders/models.py

@@ -0,0 +1,163 @@
+from django.conf import settings
+from django.db import models
+
+from apps.catalog.models import Brand, Product, Service
+
+
+class OrderStatus(models.TextChoices):
+    NEW = 'new', 'Новый'
+    CONFIRMED = 'confirmed', 'Подтверждён'
+    PAID = 'paid', 'Оплачен'          # этап 2
+    ASSEMBLED = 'assembled', 'Собран'
+    SHIPPED = 'shipped', 'Передан в доставку'  # этап 2
+    DONE = 'done', 'Выполнен'
+    CANCELLED = 'cancelled', 'Отменён'
+    REFUNDED = 'refunded', 'Возврат'   # этап 2
+
+
+class DeliveryMethod(models.TextChoices):
+    PICKUP = 'pickup', 'Самовывоз'
+    COURIER = 'courier', 'Доставка по договорённости'  # этап 1
+    CDEK = 'cdek', 'СДЭК'                               # этап 2
+
+
+class PaymentMethod(models.TextChoices):
+    BY_AGREEMENT = 'by_agreement', 'По договорённости (напрямую продавцу)'
+    ONLINE = 'online', 'Онлайн через агрегатор'  # этап 2
+
+
+class PickupPoint(models.Model):
+    """Пункт выдачи (ТЗ §4: PickupPoint)."""
+
+    name = models.CharField('Название', max_length=200)
+    address = models.CharField('Адрес', max_length=300)
+    working_hours = models.CharField('Часы работы', max_length=200, blank=True)
+    partner = models.CharField('Партнёр', max_length=200, blank=True)
+    is_active = models.BooleanField('Активен', default=True)
+
+    class Meta:
+        verbose_name = 'Пункт выдачи'
+        verbose_name_plural = 'Пункты выдачи'
+        ordering = ('name',)
+
+    def __str__(self):
+        return f'{self.name} ({self.address})'
+
+
+class Order(models.Model):
+    """Заказ / заявка (ТЗ §4: Order)."""
+
+    buyer = models.ForeignKey(
+        settings.AUTH_USER_MODEL, on_delete=models.PROTECT,
+        related_name='orders', verbose_name='Покупатель',
+    )
+    status = models.CharField(
+        'Статус', max_length=20, choices=OrderStatus.choices,
+        default=OrderStatus.NEW,
+    )
+    delivery_method = models.CharField(
+        'Способ получения', max_length=20,
+        choices=DeliveryMethod.choices, default=DeliveryMethod.PICKUP,
+    )
+    address = models.CharField('Адрес доставки', max_length=300, blank=True)
+    pickup_point = models.ForeignKey(
+        PickupPoint, null=True, blank=True, on_delete=models.SET_NULL,
+        related_name='orders', verbose_name='Пункт выдачи',
+    )
+    payment_method = models.CharField(
+        'Способ оплаты', max_length=20,
+        choices=PaymentMethod.choices, default=PaymentMethod.BY_AGREEMENT,
+    )
+    customer_comment = models.TextField('Комментарий покупателя', blank=True)
+
+    total = models.DecimalField('Сумма', max_digits=12, decimal_places=2, default=0)
+    commission = models.DecimalField(
+        'Комиссия площадки', max_digits=12, decimal_places=2, default=0,
+    )
+
+    created_at = models.DateTimeField('Создан', auto_now_add=True)
+    updated_at = models.DateTimeField('Обновлён', auto_now=True)
+
+    class Meta:
+        verbose_name = 'Заказ'
+        verbose_name_plural = 'Заказы'
+        ordering = ('-created_at',)
+
+    def __str__(self):
+        return f'Заказ №{self.pk}'
+
+    def recalculate_total(self):
+        self.total = sum((item.line_total for item in self.items.all()), start=0)
+        self.save(update_fields=['total'])
+
+
+class OrderItem(models.Model):
+    """Позиция заказа. Может относиться к товару или к услуге (ТЗ §4)."""
+
+    order = models.ForeignKey(
+        Order, on_delete=models.CASCADE, related_name='items',
+        verbose_name='Заказ',
+    )
+    brand = models.ForeignKey(
+        Brand, on_delete=models.PROTECT, related_name='order_items',
+        verbose_name='Бренд',
+    )
+    product = models.ForeignKey(
+        Product, null=True, blank=True, on_delete=models.SET_NULL,
+        related_name='order_items', verbose_name='Товар',
+    )
+    service = models.ForeignKey(
+        Service, null=True, blank=True, on_delete=models.SET_NULL,
+        related_name='order_items', verbose_name='Услуга',
+    )
+    name = models.CharField('Название позиции', max_length=255)
+    price = models.DecimalField('Цена за единицу', max_digits=12, decimal_places=2)
+    quantity = models.PositiveIntegerField('Количество', default=1)
+
+    class Meta:
+        verbose_name = 'Позиция заказа'
+        verbose_name_plural = 'Позиции заказа'
+
+    def __str__(self):
+        return f'{self.name} × {self.quantity}'
+
+    @property
+    def line_total(self):
+        return self.price * self.quantity
+
+
+class Favorite(models.Model):
+    """Избранное покупателя (ТЗ §3.2, §3.3)."""
+
+    user = models.ForeignKey(
+        settings.AUTH_USER_MODEL, on_delete=models.CASCADE,
+        related_name='favorites', verbose_name='Пользователь',
+    )
+    product = models.ForeignKey(
+        Product, null=True, blank=True, on_delete=models.CASCADE,
+        related_name='favorited_by', verbose_name='Товар',
+    )
+    service = models.ForeignKey(
+        Service, null=True, blank=True, on_delete=models.CASCADE,
+        related_name='favorited_by', verbose_name='Услуга',
+    )
+    created_at = models.DateTimeField('Добавлено', auto_now_add=True)
+
+    class Meta:
+        verbose_name = 'Избранное'
+        verbose_name_plural = 'Избранное'
+        constraints = [
+            models.UniqueConstraint(
+                fields=('user', 'product'),
+                condition=models.Q(product__isnull=False),
+                name='uniq_favorite_user_product',
+            ),
+            models.UniqueConstraint(
+                fields=('user', 'service'),
+                condition=models.Q(service__isnull=False),
+                name='uniq_favorite_user_service',
+            ),
+        ]
+
+    def __str__(self):
+        return f'{self.user} → {self.product or self.service}'