from decimal import Decimal

from django.db.models import Sum
from qrcode import constants as qr_constants
from qrcode.main import QRCode

from shop.models import Cart, CartItem
from web.settings import ANONYMOUS_CART_ID_COOKIE_NAME


def get_or_create_cart(request) -> [Cart, bool]:
    created = False
    if not request.user.is_authenticated:
        uid = request.COOKIES.get(ANONYMOUS_CART_ID_COOKIE_NAME)

        if uid:
            cart = Cart.objects.get(uuid=uid)
        else:
            cart = Cart.objects.create(user=None)
            created = True
    else:
        cart, created = Cart.objects.get_or_create(user=request.user)

    return cart, created


def get_cart_total(cart: Cart):
    return CartItem.objects.filter(cart=cart).annotate(cart_total=Sum("total")).get(
        "cart_total"
    ) or Decimal("0.00")