from django.test import TestCase
from django.utils import html
from unittest import skip
from ..forms import (
    DUPLICATE_ITEM_ERROR,
    EMPTY_ITEM_ERROR,
)
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)
        forms = parsed.cssselect('form[method=POST]')
        self.assertIn("/apps/dashboard/new_list", [form.get("action") for form in forms])
        [form] = [form for form in forms if form.get("action") == "/apps/dashboard/new_list"]
        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/new_list", 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/new_list", data={"text": "A new list item"})
        new_list = List.objects.get()
        self.assertRedirects(response, f"/apps/dashboard/{new_list.id}/")

    # Post invalid input helper
    def post_invalid_input(self):
        return self.client.post("/apps/dashboard/new_list", data={"text": ""})

    def test_for_invalid_input_nothing_saved_to_db(self):
        self.post_invalid_input()
        self.assertEqual(Item.objects.count(), 0)

    def test_for_invalid_input_renders_list_template(self):
        response = self.post_invalid_input()
        self.assertEqual(response.status_code, 200)
        self.assertTemplateUsed(response, "apps/dashboard/home.html")

    def test_for_invalid_input_shows_error_on_page(self):
        response = self.post_invalid_input()
        self.assertContains(response, html.escape(EMPTY_ITEM_ERROR))

class ListViewTest(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()
        url = f"/apps/dashboard/{mylist.id}/"
        response = self.client.get(url)
        parsed = lxml.html.fromstring(response.content)
        forms = parsed.cssselect("form[method=POST]")
        self.assertIn(url, [form.get("action") for form in forms])
        [form] = [form for form in forms if form.get("action") == url]
        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}/")

    # Post invalid input helper
    def post_invalid_input(self):
        mylist = List.objects.create()
        return self.client.post(f"/apps/dashboard/{mylist.id}/", data={"text": ""})

    def test_for_invalid_input_nothing_saved_to_db(self):
        self.post_invalid_input()
        self.assertEqual(Item.objects.count(), 0)

    def test_for_invalid_input_renders_list_template(self):
        response = self.post_invalid_input()
        self.assertEqual(response.status_code, 200)
        self.assertTemplateUsed(response, "apps/dashboard/list.html")

    def test_for_invalid_input_shows_error_on_page(self):
        response = self.post_invalid_input()
        self.assertContains(response, html.escape(EMPTY_ITEM_ERROR))

    def test_for_invalid_input_sets_is_invalid_class(self):
        response = self.post_invalid_input()
        parsed = lxml.html.fromstring(response.content)
        [input] = parsed.cssselect("input[name=text]")
        self.assertIn("is-invalid", set(input.classes))

    def test_duplicate_item_validation_errors_end_up_on_lists_page(self):
        list1 = List.objects.create()
        Item.objects.create(list=list1, text="lorem ipsum")

        response = self.client.post(
            f"/apps/dashboard/{list1.id}/",
            data={"text": "lorem ipsum"},
        )

        expected_error = html.escape(DUPLICATE_ITEM_ERROR)
        self.assertContains(response, expected_error)
        self.assertTemplateUsed(response, "apps/dashboard/list.html")
        self.assertEqual(Item.objects.all().count(), 1)