from django.test import TestCase
from django.utils import html
from ..models import Item, List
import lxml.html

class HomePageTest(TestCase):
    def test_uses_home_template(self):
        response = self.client.get('/')
        self.assertTemplateUsed(response, 'apps/dashboard/home.html')

    def test_renders_input_form(self):
        response = self.client.get('/')
        parsed = lxml.html.fromstring(response.content)
        [form] = parsed.cssselect('form[method=POST]')
        self.assertEqual(form.get('action'), '/apps/dashboard/newlist')
        inputs = form.cssselect('input')
        self.assertIn('text', [input.get('name') for input in inputs])

class NewListTest(TestCase):
    def test_can_save_a_POST_request(self):
        self. client.post('/apps/dashboard/newlist', data={'text': 'A new list item'})
        self.assertEqual(Item.objects.count(), 1)
        new_item = Item.objects.get()
        self.assertEqual(new_item.text, 'A new list item')

    def test_redirects_after_POST(self):
        response = self.client.post('/apps/dashboard/newlist', data={'text': 'A new list item'})
        new_list = List.objects.get()
        self.assertRedirects(response, f'/apps/dashboard/{new_list.id}/')

    def test_validation_errors_are_sent_back_to_home_page_template(self):
        response = self.client.post("/apps/dashboard/newlist", data={"text": ""})
        self.assertEqual(response.status_code, 200)
        self.assertTemplateUsed(response, "apps/dashboard/home.html")
        expected_error = html.escape("You can't have an empty list item")
        self.assertContains(response, expected_error)
        
    def test_invalid_list_items_never_save(self):
        self.client.post("/apps/dashboard/newlist", data={"text": ""})
        self.assertEqual(List.objects.count(), 0)
        self.assertEqual(Item.objects.count(), 0)

class DashViewTest(TestCase):
    def test_uses_list_template(self):
        mylist = List.objects.create()
        response = self.client.get(f'/apps/dashboard/{mylist.id}/')
        self.assertTemplateUsed(response, 'apps/dashboard/list.html')

    def test_renders_input_form(self):
        mylist = List.objects.create()
        response = self.client.get(f'/apps/dashboard/{mylist.id}/')
        parsed = lxml.html.fromstring(response.content)
        [form] = parsed.cssselect('form[method=POST]')
        self.assertEqual(form.get('action'), f"/apps/dashboard/{mylist.id}/")
        inputs = form.cssselect('input')
        self.assertIn('text', [input.get('name') for input in inputs])

    def test_displays_only_items_for_that_list(self):
        # Given/Arrange
        correct_list = List.objects.create()
        Item.objects.create(text='itemey 1', list=correct_list)
        Item.objects.create(text='itemey 2', list=correct_list)
        other_list = List.objects.create()
        Item.objects.create(text='other list item', list=other_list)
        # When/Act
        response = self.client.get(f'/apps/dashboard/{correct_list.id}/')
        # Then/Assert
        self.assertContains(response, 'itemey 1')
        self.assertContains(response, 'itemey 2')
        self.assertNotContains(response, 'other list item')

    def test_can_save_a_POST_request_to_an_existing_list(self):
        other_list = List.objects.create()
        correct_list = List.objects.create()

        self.client.post(
            f'/apps/dashboard/{correct_list.id}/',
            data={'text': 'A new item for an existing list'},
        )

        self.assertEqual(Item.objects.count(), 1)
        new_item = Item.objects.get()
        self.assertEqual(new_item.text, 'A new item for an existing list')
        self.assertEqual(new_item.list, correct_list)

    def test_POST_redirects_to_list_view(self):
        other_list = List.objects.create()
        correct_list = List.objects.create()

        response = self.client.post(
            f'/apps/dashboard/{correct_list.id}/',
            data={'text': 'A new item for an existing list'},
        )

        self.assertRedirects(response, f'/apps/dashboard/{correct_list.id}/')

    def test_validation_errors_end_up_on_lists_page(self):
        list_ = List.objects.create()
        response = self.client.post(
            f"/apps/dashboard/{list_.id}/",
            data={"text": ""},
        )
        self.assertEqual(response.status_code, 200)
        self.assertTemplateUsed(response, "apps/dashboard/list.html")
        expected_error = html.escape("You can't have an empty list item")
        self.assertContains(response, expected_error)