from __future__ import unicode_literals

from django.contrib.auth import get_user_model
from django.contrib.auth.models import Group
from django.core.exceptions import PermissionDenied

from common.tests import BaseTestCase
from user_management.tests import TEST_GROUP_NAME, TEST_USER_USERNAME

from ..classes import Permission
from ..models import Role
from ..permissions import permission_role_view

from .literals import TEST_ROLE_LABEL


class PermissionTestCase(BaseTestCase):
    def setUp(self):
        super(PermissionTestCase, self).setUp()
        self.user = get_user_model().objects.create(
            username=TEST_USER_USERNAME
        )
        self.group = Group.objects.create(name=TEST_GROUP_NAME)
        self.role = Role.objects.create(label=TEST_ROLE_LABEL)

    def test_no_permissions(self):
        with self.assertRaises(PermissionDenied):
            Permission.check_permissions(
                requester=self.user, permissions=(permission_role_view,)
            )

    def test_with_permissions(self):
        self.group.user_set.add(self.user)
        self.role.permissions.add(permission_role_view.stored_permission)
        self.role.groups.add(self.group)

        try:
            Permission.check_permissions(
                requester=self.user, permissions=(permission_role_view,)
            )
        except PermissionDenied:
            self.fail('PermissionDenied exception was not expected.')