import json
from io import BytesIO

from django.contrib.auth.models import User
from django.core.files.base import ContentFile
from django.test import TestCase
from django.urls import reverse
from PIL import Image

from shop.models import Product, ProductImage, ProductVariant
from shop.tests.mixins import CreateProductsMixin


class TestBackofficeHtmxContract(TestCase, CreateProductsMixin):
    def setUp(self):
        self.superuser = User.objects.create_superuser('vader', 'vader@empire.com', 'ihatesand')
        self.client.force_login(self.superuser)
        self.product = self.create_product()

    def test_product_create_is_a_full_page_not_a_modal_fragment(self):
        # ProductCreateView ya no es modal: navegar a la URL de creación siempre
        # devuelve la página completa, incluso si la petición lleva HX-Request.
        response = self.client.get(reverse('backoffice:product_create'), HTTP_HX_REQUEST='true')
        assert response.status_code == 200
        body = response.content.decode()
        assert '<html' in body
        assert 'Nuevo producto' in body

    def test_product_create_redirects_to_detail_even_with_hx_request(self):
        response = self.client.post(
            reverse('backoffice:product_create'),
            {'sku': 'HTMX-1', 'name': 'Producto htmx', 'description': '', 'stock': '0'},
            HTTP_HX_REQUEST='true',
        )
        product = Product.objects.get(sku='HTMX-1')
        assert response.status_code == 302
        assert response.url == reverse('backoffice:product_detail', args=[product.pk])
        assert 'HX-Trigger' not in response

    def test_htmx_variant_create_triggers_refresh(self):
        size_m = self.create_attribute_value('Talla', 'M')

        response = self.client.post(
            reverse('backoffice:product_variant_create', args=[self.product.pk]),
            {'sku': 'HTMX-V1', 'stock': '5', 'attribute_values': [size_m.pk]},
            HTTP_HX_REQUEST='true',
        )
        assert response.status_code == 204
        trigger = json.loads(response['HX-Trigger'])
        assert trigger['backoffice:modal-close'] is True
        assert trigger['backoffice:list-changed'] is True
        assert ProductVariant.objects.filter(sku='HTMX-V1').exists()

    def test_htmx_variant_delete_stays_and_refreshes(self):
        size_m = self.create_attribute_value('Talla', 'M')
        variant = self.create_product_variant(self.product, sku='HTMX-V2', attribute_values=[size_m])

        response = self.client.post(
            reverse('backoffice:product_variant_delete', args=[variant.pk]), HTTP_HX_REQUEST='true'
        )
        assert response.status_code == 204
        assert 'HX-Redirect' not in response
        trigger = json.loads(response['HX-Trigger'])
        assert trigger['backoffice:list-changed'] is True
        assert not ProductVariant.objects.filter(pk=variant.pk).exists()

    def test_htmx_image_upload_triggers_refresh(self):
        image = Image.new('RGB', (64, 64), '#ACACAC')
        buffer = BytesIO()
        image.save(fp=buffer, format='WEBP')
        file = ContentFile(buffer.getvalue(), name='test.webp')

        response = self.client.post(
            reverse('backoffice:product_image_create', args=[self.product.pk]),
            {'original': file},
            format='multipart',
            HTTP_HX_REQUEST='true',
        )
        assert response.status_code == 204
        trigger = json.loads(response['HX-Trigger'])
        assert trigger == {'backoffice:modal-close': True, 'backoffice:list-changed': True}
        assert ProductImage.objects.filter(product=self.product).exists()

    def test_htmx_product_delete_uses_hx_redirect_instead_of_trigger(self):
        product = self.create_product(sku='HTMX-DEL')

        response = self.client.post(reverse('backoffice:product_delete', args=[product.pk]), HTTP_HX_REQUEST='true')
        assert response.status_code == 200
        assert response['HX-Redirect'] == reverse('backoffice:product_list')
        assert 'HX-Trigger' not in response
        assert not Product.objects.filter(pk=product.pk).exists()

    def test_htmx_list_self_refresh_returns_fragment(self):
        response = self.client.get(reverse('backoffice:product_list'), HTTP_HX_REQUEST='true')
        assert response.status_code == 200
        body = response.content.decode()
        assert '<html' not in body
        assert 'id="backoffice-list"' in body

    def test_htmx_product_detail_self_refresh_returns_fragment(self):
        response = self.client.get(reverse('backoffice:product_detail', args=[self.product.pk]), HTTP_HX_REQUEST='true')
        assert response.status_code == 200
        body = response.content.decode()
        assert '<html' not in body
        assert 'id="backoffice-detail"' in body