import json

import ddt
import httpretty
import mock
from django.contrib.auth.models import Permission
from django.test import RequestFactory, override_settings
from django.urls import reverse
from oscar.core.loading import get_model

from ecommerce.extensions.api.serializers import OrderSerializer
from ecommerce.extensions.api.tests.test_authentication import AccessTokenMixin
from ecommerce.extensions.api.v2.tests.views import OrderDetailViewTestMixin
from ecommerce.extensions.fulfillment.signals import SHIPPING_EVENT_NAME
from ecommerce.extensions.fulfillment.status import ORDER
from ecommerce.extensions.test.factories import create_order
from ecommerce.tests.factories import SiteConfigurationFactory
from ecommerce.tests.mixins import ThrottlingMixin
from ecommerce.tests.testcases import TestCase

Order = get_model('order', 'Order')
ShippingEventType = get_model('order', 'ShippingEventType')


@ddt.ddt
class OrderListViewTests(AccessTokenMixin, ThrottlingMixin, TestCase):
    def setUp(self):
        super(OrderListViewTests, self).setUp()
        self.path = reverse('api:v2:order-list')
        self.user = self.create_user()
        self.token = self.generate_jwt_token_header(self.user)

    def test_not_authenticated(self):
        """ If the user is not authenticated, the view should return HTTP status 401. """
        response = self.client.get(self.path)
        self.assertEqual(response.status_code, 401)

    def assert_empty_result_response(self, response):
        """ Verifies that the view responded successfully with an empty result list. """
        self.assertEqual(response.status_code, 200)

        content = json.loads(response.content)
        self.assertEqual(content['count'], 0)
        self.assertEqual(content['results'], [])

    @httpretty.activate
    def test_oauth2_authentication(self):
        """Verify clients can authenticate with OAuth 2.0."""
        auth_header = 'Bearer {}'.format(self.DEFAULT_TOKEN)

        self.mock_user_info_response(username=self.user.username)
        response = self.client.get(self.path, HTTP_AUTHORIZATION=auth_header)
        self.assert_empty_result_response(response)

    def test_no_orders(self):
        """ If the user has no orders, the view should return an empty list. """
        self.assertFalse(self.user.orders.exists())
        response = self.client.get(self.path, HTTP_AUTHORIZATION=self.token)
        self.assert_empty_result_response(response)

    def test_with_orders(self):
        """
        The view should return a list of the user's orders, sorted reverse chronologically, filtered by current site.
        """
        order = create_order(site=self.site, user=self.user)
        site = SiteConfigurationFactory().site
        create_order(site=site, user=self.user)
        response = self.client.get(self.path, HTTP_AUTHORIZATION=self.token)
        self.assertEqual(response.status_code, 200)
        content = json.loads(response.content)

        self.assertEqual(Order.objects.count(), 2)
        self.assertEqual(content['count'], 1)
        self.assertEqual(content['results'][0]['number'], unicode(order.number))

        # Test ordering
        order_2 = create_order(site=self.site, user=self.user)
        response = self.client.get(self.path, HTTP_AUTHORIZATION=self.token)
        self.assertEqual(response.status_code, 200)
        content = json.loads(response.content)

        self.assertEqual(content['count'], 2)
        self.assertEqual(content['results'][0]['number'], unicode(order_2.number))
        self.assertEqual(content['results'][1]['number'], unicode(order.number))

    def test_with_other_users_orders(self):
        """ The view should only return orders for the authenticated users. """
        other_user = self.create_user()
        create_order(site=self.site, user=other_user)
        response = self.client.get(self.path, HTTP_AUTHORIZATION=self.token)
        self.assert_empty_result_response(response)

        order = create_order(site=self.site, user=self.user)
        response = self.client.get(self.path, HTTP_AUTHORIZATION=self.token)
        content = json.loads(response.content)
        self.assertEqual(content['count'], 1)
        self.assertEqual(content['results'][0]['number'], unicode(order.number))

    @ddt.unpack
    @ddt.data(
        (True, True),
        (True, False),
    )
    def test_staff_superuser(self, is_staff, is_superuser):
        """ The view should return all orders for when authenticating as a staff member or superuser. """
        admin_user = self.create_user(is_staff=is_staff, is_superuser=is_superuser)
        order = create_order(site=self.site, user=self.user)

        response = self.client.get(self.path, HTTP_AUTHORIZATION=self.generate_jwt_token_header(admin_user))
        content = json.loads(response.content)
        self.assertEqual(content['count'], 1)
        self.assertEqual(content['results'][0]['number'], unicode(order.number))

    def test_user_information(self):
        """ Make sure that the correct user information is returned. """
        admin_user = self.create_user(is_staff=True, is_superuser=True)
        order = create_order(site=self.site, user=admin_user)

        response = self.client.get(self.path, HTTP_AUTHORIZATION=self.generate_jwt_token_header(admin_user))
        content = json.loads(response.content)
        self.assertEqual(content['count'], 1)
        self.assertEqual(content['results'][0]['number'], unicode(order.number))
        self.assertEqual(content['results'][0]['user']['email'], admin_user.email)
        self.assertEqual(content['results'][0]['user']['username'], admin_user.username)

    def test_username_filter_with_staff(self):
        """ Verify the staff user can filter data by username."""

        # create two orders for different users
        order = create_order(site=self.site, user=self.user)
        other_user = self.create_user()
        other_order = create_order(site=self.site, user=other_user)

        requester = self.create_user(is_staff=True)
        self.client.login(email=requester.email, password=self.password)

        self.assert_list_with_username_filter(self.user, order)
        self.assert_list_with_username_filter(other_user, other_order)

    def test_username_filter_with_non_staff(self):
        """Non staff users are not allowed to filter on any other username."""
        requester = self.create_user(is_staff=False)
        self.client.login(username=requester.username, password=self.password)

        response = self.client.get(self.path, {'username': self.user.username})
        self.assertEqual(response.status_code, 403)

    def assert_list_with_username_filter(self, user, order):
        """ Helper method for making assertions. """

        response = self.client.get(self.path, {'username': user.username})
        self.assertEqual(response.status_code, 200)

        self.assertEqual(
            response.data['results'][0],
            OrderSerializer(order, context={'request': RequestFactory(SERVER_NAME=self.site.domain).get('/')}).data
        )


@ddt.ddt
@override_settings(ECOMMERCE_SERVICE_WORKER_USERNAME='test-service-user')
class OrderFulfillViewTests(TestCase):
    def setUp(self):
        super(OrderFulfillViewTests, self).setUp()
        ShippingEventType.objects.get_or_create(name=SHIPPING_EVENT_NAME)

        # Use the ecommerce worker service user in order to cover
        # request throttling code in extensions/api/throttles.py
        self.user = self.create_user(is_staff=True, username='test-service-user')
        self.change_order_permission = Permission.objects.get(codename='change_order')
        self.user.user_permissions.add(self.change_order_permission)

        self.client.login(username=self.user.username, password=self.password)

        self.order = create_order(site=self.site, user=self.user)
        self.url = reverse('api:v2:order-fulfill', kwargs={'number': self.order.number})

    def _put_to_view(self):
        """
        PUT to the view being tested.

        Returns:
            Response
        """
        return self.client.put(self.url)

    def _assert_fulfillment_success(self):
        """Verify that order fulfillment was successful. The view should return HTTP 200."""
        with mock.patch('ecommerce.extensions.order.processing.EventHandler.handle_shipping_event') as mocked:
            def handle_shipping_event(order, _event_type, _lines, _line_quantities, **_kwargs):
                order.status = ORDER.COMPLETE
                order.save()
                return order

            mocked.side_effect = handle_shipping_event
            response = self._put_to_view()

        self.assertTrue(mocked.called)
        self.assertEqual(200, response.status_code)

        return response

    @ddt.data('delete', 'get', 'post')
    def test_delete_get_post_prohibited(self, method):
        """Verify that the view does not allow DELETE, GET, or POST."""
        response = getattr(self.client, method)(self.url)

        # TODO: Since the view is routed to PUT and PATCH, DELETE, GET, and
        # POST *should* all be met with 405. However, permissions checks appear
        # to occur first. As a result, when a user with change permissions
        # attempts a POST or DELETE, the response has status code 403, since
        # the user doesn't have permission to create or delete orders.
        self.assertIn(response.status_code, [405, 403])

    def test_login_required(self):
        """ The view should return HTTP 401 status if the user is not logged in. """
        self.client.logout()
        self.assertEqual(401, self._put_to_view().status_code)

    def test_change_permissions_required(self):
        """
        Verify that staff users with permission to change Order objects are
        able to modify orders on behalf of other users.
        """
        customer = self.create_user(username='customer')
        customer_order = create_order(site=self.site, user=customer)
        self.url = reverse('api:v2:order-fulfill', kwargs={'number': customer_order.number})

        self._assert_fulfillment_success()

        # If the requesting user does not have the correct permissions, the view should
        # return HTTP 403 status.
        self.user.user_permissions.remove(self.change_order_permission)
        self.assertEqual(403, self._put_to_view().status_code)

    def test_order_complete_state_disallowed(self):
        """ If the order is Complete, the view must return an HTTP 406. """
        self.order.status = ORDER.COMPLETE
        self.order.save()
        self.assertEqual(406, self._put_to_view().status_code)

    @ddt.data(ORDER.OPEN, ORDER.FULFILLMENT_ERROR)
    def test_ideal_conditions(self, order_status):
        """
        If the user is authenticated/authorized, and the order is in the Open or Fulfillment Error
        states, the view should attempt to fulfill the order. The view should return HTTP 200.
        """
        self.order.status = order_status
        self.order.save()

        response = self._assert_fulfillment_success()

        # Reload the order from the DB and check its status
        self.order = Order.objects.get(number=self.order.number)
        self.assertEqual(unicode(self.order.number), response.data['number'])
        self.assertEqual(self.order.status, response.data['status'])

    def test_fulfillment_failed(self):
        """ If fulfillment fails, the view should return HTTP 500. """
        self.order.status = ORDER.FULFILLMENT_ERROR
        self.order.save()

        response = self._put_to_view()
        self.assertEqual(500, response.status_code)


class OrderDetailViewTests(OrderDetailViewTestMixin, TestCase):
    @property
    def url(self):
        return reverse('api:v2:order-detail', kwargs={'number': self.order.number})
