from django.conf import settings
from django.core.paginator import Paginator

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


class FilteredQuerysetMixin:
    queryset = None
    filter_class = None

    def get_filter_class(self):
        return self.filter_class

    def get_queryset(self):
        filter_cls = self.get_filter_class()
        filter_obj = filter_cls(self.request.GET)
        filter_obj.is_valid()
        qs = filter_obj.filter_queryset(self.queryset)
        return qs


class PaginatedQuerysetMixin:
    objects_per_page = settings.ITEMS_PER_PAGE or 20

    def get_paginated_queryset(self, qs):
        paginator = Paginator(qs, self.objects_per_page)
        page = self.request.GET.get("page", 1)
        qs = paginator.get_page(page)
        return qs


class CartMixin:
    def get_cart(self):
        if not self.request.user.is_authenticated:
            uid = self.request.COOKIES.get(ANONYMOUS_CART_ID_COOKIE_NAME)
            cart = Cart.objects.get(uuid=uid)
        else:
            cart = Cart.objects.filter(user=self.request.user).first()
        return cart