from django.contrib.auth import get_user_model
from django.contrib.auth.models import Group, Permission
from django.test import TestCase
from django.urls import reverse

from wagtail.models import Page
from wagtail.test.testapp.models import SimplePage, StreamPage
from wagtail.test.utils import WagtailTestUtils


class TestDraftAccess(WagtailTestUtils, TestCase):
    """Tests for the draft view access restrictions."""

    def setUp(self):
        # Find root page
        self.root_page = Page.objects.get(id=2)

        # Add child page
        self.child_page = SimplePage(
            title="Hello world!",
            slug="hello-world",
            content="hello",
        )
        self.root_page.add_child(instance=self.child_page)

        # Add stream page (which has empty preview_modes, and so doesn't allow viewing draft)
        self.stream_page = StreamPage(title="stream page", body=[("text", "hello")])
        self.root_page.add_child(instance=self.stream_page)

        # create user with admin access (but not draft_view access)
        user = self.create_user(username="bob", password="password")
        user.user_permissions.add(
            Permission.objects.get(
                content_type__app_label="wagtailadmin", codename="access_admin"
            )
        )

    def test_draft_access_admin(self):
        """Test that admin can view draft."""
        # Login as admin
        self.user = self.login()

        # Try getting page draft
        response = self.client.get(
            reverse("wagtailadmin_pages:view_draft", args=(self.child_page.id,))
        )

        # User can view
        self.assertEqual(response.status_code, 200)

    def test_page_without_preview_modes_is_unauthorised(self):
        # Login as admin
        self.user = self.login()

        # Try getting page draft
        response = self.client.get(
            reverse("wagtailadmin_pages:view_draft", args=(self.stream_page.id,))
        )

        # Unauthorised response (because this page type has previewing disabled)
        self.assertRedirects(response, "/admin/")

    def test_draft_access_unauthorised(self):
        """Test that user without edit/publish permission can't view draft."""
        self.login(username="bob", password="password")

        # Try getting page draft
        response = self.client.get(
            reverse("wagtailadmin_pages:view_draft", args=(self.child_page.id,))
        )

        # User gets redirected to the home page
        self.assertEqual(response.status_code, 302)

    def test_draft_access_authorised(self):
        """Test that user with edit permission can view draft."""
        # give user the permission to edit page
        user = get_user_model().objects.get(email="bob@example.com")
        user.groups.add(Group.objects.get(name="Moderators"))
        user.save()

        self.login(username="bob", password="password")

        # Get add subpage page
        response = self.client.get(
            reverse("wagtailadmin_pages:view_draft", args=(self.child_page.id,))
        )

        # User can view
        self.assertEqual(response.status_code, 200)

    def test_middleware_response_is_returned(self):
        """
        If middleware returns a response while serving a page preview, that response should be
        returned back to the user
        """
        self.login()
        response = self.client.get(
            reverse("wagtailadmin_pages:view_draft", args=(self.child_page.id,)),
            HTTP_USER_AGENT="EvilHacker",
        )
        self.assertEqual(response.status_code, 403)

    def test_show_edit_link_in_userbar(self):
        self.login()
        response = self.client.get(
            reverse("wagtailadmin_pages:view_draft", args=(self.child_page.id,))
        )
        # Should show edit link in the userbar
        # https://github.com/wagtail/wagtail/issues/10002
        self.assertContains(response, "Edit this page")
        self.assertContains(
            response, reverse("wagtailadmin_pages:edit", args=(self.child_page.id,))
        )