from decimal import Decimal

from django.db import models
from django.db.models import Prefetch
from django.http import HttpResponse
from django.shortcuts import get_object_or_404, render
from django.urls import reverse
from django.utils.text import gettext_lazy as _
from django.views.generic import TemplateView

from config.mixins import HTMXFormComponent
from shop.filters import ProductFilter
from shop.models import CartItem, CustomerAddress, Product, ProductPrice, ShippingMethod, WishlistedProduct
from users.forms.change_password import ChangePasswordForm
from users.forms.info import UserInfoForm
from web.forms import CustomerAddressForm
from web.mixins import FilteredQuerysetMixin, PaginatedQuerysetMixin
from web.settings import ANONYMOUS_CART_ID_COOKIE_NAME
from web.utils import get_or_create_cart


class ListProducts(TemplateView, FilteredQuerysetMixin, PaginatedQuerysetMixin):
    template_name = 'web/list_products.html'
    queryset = Product.objects.filter(hidden=False).prefetch_related(
        'images', Prefetch('prices', queryset=ProductPrice.objects.filter(current=True), to_attr='current_prices')
    )
    filter_class = ProductFilter

    def get_context_data(self, **kwargs):
        qs = self.get_queryset()
        page = self.get_paginated_queryset(qs)

        return {
            'current_page': page.number,
            'num_pages': page.paginator.num_pages,
            'page': page,
            'has_next_page': page.has_next(),
            'has_previous_page': page.has_previous(),
        }


class ListWishlistedProducts(TemplateView, FilteredQuerysetMixin, PaginatedQuerysetMixin):
    template_name = 'web/list_products.html'
    queryset = Product.objects.filter(hidden=False).prefetch_related('images')
    filter_class = ProductFilter

    def get_queryset(self):
        product_ids = WishlistedProduct.objects.filter(user=self.request.user).values_list('product', flat=True)
        return super().get_queryset().filter(pk__in=product_ids).distinct()

    def get_context_data(self, **kwargs):
        qs = self.get_queryset()
        page = self.get_paginated_queryset(qs)

        return {
            'current_page': page.number,
            'num_pages': page.paginator.num_pages,
            'page': page,
            'has_next_page': page.has_next(),
            'has_previous_page': page.has_previous(),
        }


def cart_dropdown(request, *args, **kwargs):
    cart, created = get_or_create_cart(request)

    response = render(request, 'components/cart/cart_navbar.html', context={'cart': cart})

    if not request.user.is_authenticated:
        response.set_cookie(ANONYMOUS_CART_ID_COOKIE_NAME, cart.uuid, samesite='strict')
    return response


def cart(request, *args, **kwargs):
    cart, created = get_or_create_cart(request)
    items = CartItem.objects.filter(cart=cart)

    base_total = Decimal('0.00')
    tax_total = Decimal('0.00')

    for item in items:
        price = ProductPrice.objects.filter(product=item.product, current=True).first()
        base_total += price.price * item.quantity
        tax_total += round(price.price * Decimal(price.tax.value / 100) * item.quantity, 2)

    total = base_total + tax_total

    if request.user.is_authenticated:
        billing_address = CustomerAddress.objects.filter(
            user=request.user, address_type=CustomerAddress.Types.BILLING, default=True
        ).first()
        shipping_address = CustomerAddress.objects.filter(
            user=request.user, address_type=CustomerAddress.Types.SHIPPING
        ).first()
    else:
        billing_address = None
        shipping_address = None

    shipping_methods = ShippingMethod.objects.all()

    response = render(
        request,
        'components/cart/cart.html',
        context={
            'cart': cart,
            'items': items,
            'total': total,
            'base_total': base_total,
            'tax_total': tax_total,
            'billing_address': billing_address,
            'shipping_address': shipping_address,
            'shipping_methods': shipping_methods,
        },
    )

    if not request.user.is_authenticated:
        response.set_cookie(ANONYMOUS_CART_ID_COOKIE_NAME, cart.uuid, samesite='strict')
    return response


class WishlistButton(TemplateView):
    template_name = 'components/products/wishlist_button.html'

    def get_context_data(self, **kwargs):
        product = get_object_or_404(Product, pk=self.kwargs.get('pk'))
        is_wishlisted = WishlistedProduct.objects.filter(user=self.request.user, product=product).exists()

        return {'is_wishlisted': is_wishlisted, 'product': product}


class UserInfoFormComponentView(HTMXFormComponent):
    form_class = UserInfoForm
    hx_trigger = 'updated_user_info'
    save_button_text = _('Actualizar datos')

    def get_object(self) -> models.Model:
        return self.request.user

    def get_view_name(self):
        return reverse('web:user_info_component')

    def get_initial_values(self, instance):
        return {'email': instance.email, 'first_name': instance.first_name, 'last_name': instance.last_name}


class ChangePasswordFormComponentView(HTMXFormComponent):
    form_class = ChangePasswordForm
    hx_trigger = 'changed_password'
    save_button_text = _('Cambiar contraseña')

    def get_form(self, initial=True):
        if initial:
            return self.form_class(user=self.request.user)

        return self.form_class(self.request.user, self.request.POST)

    def get_object(self) -> models.Model:
        return self.request.user

    def get_view_name(self):
        return reverse('web:change_password_component')


class ListCustomerAddressComponent(TemplateView):
    template_name = 'components/users/retrieve_update_address.html'

    def get_context_data(self, **kwargs):
        return {'customer_addresses': CustomerAddress.objects.filter(user=self.request.user)}


def update_customer_address(request, pk):
    customer_address = get_object_or_404(CustomerAddress, pk=pk, user=request.user)
    form = CustomerAddressForm(request.POST, instance=customer_address)

    if form.is_valid():
        form.save()
        return HttpResponse(status=200, headers={'HX-Trigger': 'updated_addresses'})

    return HttpResponse(form.errors, status=400)


list_products = ListProducts.as_view()
list_wishlisted_products = ListWishlistedProducts.as_view()
wishlist_button = WishlistButton.as_view()

user_info_component = UserInfoFormComponentView.as_view()
change_password_component = ChangePasswordFormComponentView.as_view()
list_customer_addresses_component = ListCustomerAddressComponent.as_view()