from fastapi import APIRouter, HTTPException

carts = []  # In-memory storage

router = APIRouter()

@router.post("/cart")
async def add_to_cart(
    user_id: str,
    item_id: str,
    quantity: int = 1
):
    """Add item to user's cart"""
    cart = next((c for c in carts if c["user_id"] == user_id), None)
    
    if not cart:
        cart = {
            "user_id": user_id,
            "items": []
        }
        carts.append(cart)

    cart["items"].append({
        "item_id": item_id,
        "quantity": quantity
    })

    return {
        "message": "Item added to cart",
        "cart_id": user_id,
        "items": cart["items"],
        "features": {
            "max_items": 10,
            "expires_in": 3600
        }
    }