from typing import List

from sqlalchemy.orm import Session

from app.models.cart import CartItem
from app.models.order import Order, OrderItem
from app.schemas.order import OrderCreate, OrderUpdate
from app.services.base import CRUDBase


class OrderService(CRUDBase[Order, OrderCreate, OrderUpdate]):
    def get_user_orders(
        self, db: Session, *, user_id: int, skip: int = 0, limit: int = 100
    ) -> List[Order]:
        return (
            db.query(Order)
            .filter(Order.user_id == user_id)
            .offset(skip)
            .limit(limit)
            .all()
        )

    def create_from_cart(
        self, db: Session, *, user_id: int, cart_items: List[CartItem], shipping_address: str
    ) -> Order:
        # Calculate total amount
        total_amount = sum(item.unit_price * item.quantity for item in cart_items)

        # Create order
        db_obj = Order(
            user_id=user_id,
            total_amount=total_amount,
            shipping_address=shipping_address
        )
        db.add(db_obj)
        db.flush()  # Flush to get the order ID

        # Create order items
        for cart_item in cart_items:
            order_item = OrderItem(
                order_id=db_obj.id,
                product_id=cart_item.product_id,
                quantity=cart_item.quantity,
                unit_price=cart_item.unit_price
            )
            db.add(order_item)

        db.commit()
        db.refresh(db_obj)
        return db_obj

order_service = OrderService(Order)