# -*- coding: utf-8 -*-
from unittest import mock

from django.contrib.auth.models import (
    AnonymousUser, Group as DjangoGroup, User,
)
from django.contrib.contenttypes.models import ContentType
from django.core import signing
from django.core.urlresolvers import reverse
from django.test import RequestFactory, TestCase

from kfet.models import Account

from . import KFET_GENERIC_TRIGRAMME, KFET_GENERIC_USERNAME
from .backends import AccountBackend, GenericBackend
from .fields import GroupsField, CorePermissionsField
from .middleware import TemporaryAuthMiddleware
from .models import GenericTeamToken, Group, Permission
from .utils import get_kfet_generic_user
from .views import GenericLoginView


##
# Forms and form fields
##


class CorePermissionsFieldTests(TestCase):

    def setUp(self):
        kf_ct = ContentType.objects.get_for_model(GenericTeamToken)
        self.kf_perm1 = Permission.objects.create(
            content_type=kf_ct, codename='code1')
        self.kf_perm2 = Permission.objects.create(
            content_type=kf_ct, codename='code2')
        self.kf_perm3 = Permission.objects.create(
            content_type=kf_ct, codename='code3')

        ot_ct = ContentType.objects.get_for_model(Permission)
        self.ot_perm = Permission.objects.create(
            content_type=ot_ct, codename='code')

    def test_choices(self):
        """
        Only K-Fêt permissions are selectable.
        """
        field = CorePermissionsField()
        for p in [self.kf_perm1, self.kf_perm2, self.kf_perm3]:
            self.assertIn(p, field.queryset)
        self.assertNotIn(self.ot_perm, field.queryset)


class GroupsFieldTests(TestCase):

    def setUp(self):
        self.kf_group1 = Group.objects.create(name='KF Group1')
        self.kf_group2 = Group.objects.create(name='KF Group2')
        self.kf_group3 = Group.objects.create(name='KF Group3')
        self.ot_group = DjangoGroup.objects.create(name='OT Group')

    def test_choices(self):
        """
        Only K-Fêt groups are selectable.
        """
        field = GroupsField()
        self.assertQuerysetEqual(
            field.queryset,
            map(repr, [self.kf_group1, self.kf_group2, self.kf_group3]),
            ordered=False,
        )


class GroupFormTests(TestCase):

    def setUp(self):
        self.user = User.objects.create(username='user')
        self.kf_group = Group.objects.create(name='A Group')

        self.kf_perm1 = Permission.kfetcore.get(codename='is_team')
        self.kf_perm2 = Permission.kfetcore.get(codename='add_checkout')

        ot_ct = ContentType.objects.get_for_model(Permission)
        self.ot_perm = Permission.objects.create(
            content_type=ot_ct, codename='cool')

    def test_creation(self):
        from .forms import GroupForm
        data = {
            'name': 'Another Group',
            'permissions': [self.kf_perm1.pk],
        }
        form = GroupForm(data)
        instance = form.save()

        self.assertEqual(instance.name, 'Another Group')
        self.assertQuerysetEqual(
            instance.permissions.all(), map(repr, [self.kf_perm1]))

    def test_keep_others(self):
        """
        Non-kfet permissions of Group are kept when the form is submitted.
        Regression test for #168.
        """
        from .forms import GroupForm
        self.kf_group.permissions.add(self.ot_perm)

        selected = [self.kf_perm1, self.kf_perm2]

        data = {
            'name': 'A Group',
            'permissions': [str(p.pk) for p in selected],
        }

        form = GroupForm(data, instance=self.kf_group)
        form.save()

        self.assertQuerysetEqual(
            self.kf_group.permissions.all(),
            map(repr, [self.ot_perm] + selected),
            ordered=False,
        )


class UserGroupFormTests(TestCase):

    def setUp(self):
        # create user
        self.user = User.objects.create(username="foo", password="foo")

        # create some K-Fêt groups
        self.kf_group1 = Group.objects.create(name='KF Group1')
        self.kf_group2 = Group.objects.create(name='KF Group2')
        self.kf_group3 = Group.objects.create(name='KF Group3')

        # create a non-K-Fêt group
        self.ot_group = DjangoGroup.objects.create(name="OT Group")

    def test_keep_others(self):
        """
        User stays in its non-K-Fêt groups.
        Regression test for #161.
        """
        from .forms import UserGroupForm
        # add user to a non-K-Fêt group
        self.user.groups.add(self.ot_group)

        # add user to some K-Fêt groups through UserGroupForm
        selected = [self.kf_group1, self.kf_group2]
        data = {'groups': [str(g.pk) for g in selected]}
        form = UserGroupForm(data, instance=self.user)
        form.save()

        transform = lambda g: g.pk
        self.assertQuerysetEqual(
            self.user.groups.all(),
            map(transform, [self.ot_group] + selected),
            ordered=False, transform=transform,
        )


##
# Models
##

class PermissionTests(TestCase):

    def test_manager_kfet(self):
        """
        'kfet' manager only returns K-Fêt permissions.
        """
        kf_ct = ContentType.objects.get_for_model(GenericTeamToken)
        kf_perm1 = Permission.objects.create(
            content_type=kf_ct, codename='code1')
        kf_perm2 = Permission.objects.create(
            content_type=kf_ct, codename='code2')
        kf_perm3 = Permission.objects.create(
            content_type=kf_ct, codename='code3')

        self.assertEqual(Permission.kfetcore.get(codename='code1'), kf_perm1)
        self.assertEqual(Permission.kfetcore.get(codename='code2'), kf_perm2)
        self.assertEqual(Permission.kfetcore.get(codename='code3'), kf_perm3)

        ot_ct = ContentType.objects.get_for_model(Permission)
        Permission.objects.create(content_type=ot_ct, codename='code')

        with self.assertRaises(Permission.DoesNotExist):
            Permission.kfetcore.get(codename='code')


##
# K-Fêt generic user object
##

class KFetGenericUserTests(TestCase):

    def test_exists(self):
        """
        The account is set up when app is ready, so it should exist.
        """
        generic = Account.objects.get_generic()
        self.assertEqual(generic.trigramme, KFET_GENERIC_TRIGRAMME)
        self.assertEqual(generic.user.username, KFET_GENERIC_USERNAME)
        self.assertEqual(get_kfet_generic_user(), generic.user)


##
# Backends
##

class AccountBackendTests(TestCase):

    def setUp(self):
        self.request = RequestFactory().get('/')

    def test_valid(self):
        acc = Account(trigramme='000')
        acc.change_pwd('valid')
        acc.save({'username': 'user'})

        auth = AccountBackend().authenticate(
            self.request, kfet_password='valid')

        self.assertEqual(auth, acc.user)

    def test_invalid(self):
        auth = AccountBackend().authenticate(
            self.request, kfet_password='invalid')
        self.assertIsNone(auth)


class GenericBackendTests(TestCase):

    def setUp(self):
        self.request = RequestFactory().get('/')

    def test_valid(self):
        token = GenericTeamToken.objects.create_token()

        auth = GenericBackend().authenticate(
            self.request, kfet_token=token.token)

        self.assertEqual(auth, get_kfet_generic_user())
        self.assertEqual(GenericTeamToken.objects.all().count(), 0)

    def test_invalid(self):
        auth = GenericBackend().authenticate(
            self.request, kfet_token='invalid')
        self.assertIsNone(auth)


##
# Views
##

class GenericLoginViewTests(TestCase):

    def setUp(self):
        patcher_messages = mock.patch('gestioncof.signals.messages')
        patcher_messages.start()
        self.addCleanup(patcher_messages.stop)

        user_acc = Account(trigramme='000')
        user_acc.save({'username': 'user'})
        self.user = user_acc.user
        self.user.set_password('user')
        self.user.save()

        team_acc = Account(trigramme='100')
        team_acc.save({'username': 'team'})
        self.team = team_acc.user
        self.team.set_password('team')
        self.team.save()
        self.team.user_permissions.add(
            Permission.objects.get(
                content_type__app_label='kfet', codename='is_team'),
        )

        self.url = reverse('kfet.login.generic')
        self.generic_user = get_kfet_generic_user()

    def test_url(self):
        self.assertEqual(self.url, '/k-fet/login/generic')

    def test_notoken_get(self):
        """
        Send confirmation for user to emit POST request, instead of GET.
        """
        self.client.login(username='team', password='team')

        r = self.client.get(self.url)

        self.assertEqual(r.status_code, 200)
        self.assertTemplateUsed(r, 'kfet/confirm_form.html')

    def test_notoken_post(self):
        """
        POST request without token in COOKIES sets a token and redirects to
        logout url.
        """
        self.client.login(username='team', password='team')

        r = self.client.post(self.url)

        self.assertRedirects(
            r, '/logout?next={}'.format(self.url),
            fetch_redirect_response=False,
        )

    def test_notoken_not_team(self):
        """
        Logged in user must be a team user to initiate login as generic user.
        """
        self.client.login(username='user', password='user')

        # With GET.
        r = self.client.get(self.url)
        self.assertRedirects(
            r, '/login?next={}'.format(self.url),
            fetch_redirect_response=False,
        )

        # Also with POST.
        r = self.client.post(self.url)
        self.assertRedirects(
            r, '/login?next={}'.format(self.url),
            fetch_redirect_response=False,
        )

    def _set_signed_cookie(self, client, key, value):
        signed_value = signing.get_cookie_signer(salt=key).sign(value)
        client.cookies.load({key: signed_value})

    def _is_cookie_deleted(self, client, key):
        try:
            self.assertNotIn(key, client.cookies)
        except AssertionError:
            try:
                cookie = client.cookies[key]
                # It also can be emptied.
                self.assertEqual(cookie.value, '')
                self.assertEqual(
                    cookie['expires'], 'Thu, 01-Jan-1970 00:00:00 GMT')
                self.assertEqual(cookie['max-age'], 0)
            except AssertionError:
                raise AssertionError("The cookie '%s' still exists." % key)

    def test_withtoken_valid(self):
        """
        The kfet generic user is logged in.
        """
        token = GenericTeamToken.objects.create(token='valid')
        self._set_signed_cookie(
            self.client, GenericLoginView.TOKEN_COOKIE_NAME, 'valid')

        r = self.client.get(self.url)

        self.assertRedirects(r, reverse('kfet.kpsul'))
        self.assertEqual(r.wsgi_request.user, self.generic_user)
        self._is_cookie_deleted(
            self.client, GenericLoginView.TOKEN_COOKIE_NAME)
        with self.assertRaises(GenericTeamToken.DoesNotExist):
            token.refresh_from_db()

    def test_withtoken_invalid(self):
        """
        If token is invalid, delete it and try again.
        """
        self._set_signed_cookie(
            self.client, GenericLoginView.TOKEN_COOKIE_NAME, 'invalid')

        r = self.client.get(self.url)

        self.assertRedirects(r, self.url, fetch_redirect_response=False)
        self.assertEqual(r.wsgi_request.user, AnonymousUser())
        self._is_cookie_deleted(
            self.client, GenericLoginView.TOKEN_COOKIE_NAME)

    def test_flow_ok(self):
        """
        A team user is logged in as the kfet generic user.
        """
        self.client.login(username='team', password='team')
        next_url = '/k-fet/'

        r = self.client.post(
            '{}?next={}'.format(self.url, next_url), follow=True)

        self.assertEqual(r.wsgi_request.user, self.generic_user)
        self.assertEqual(r.wsgi_request.path, '/k-fet/')


##
# Temporary authentication
#
# Includes:
#   - TemporaryAuthMiddleware
#   - temporary_auth context processor
##

class TemporaryAuthTests(TestCase):

    def setUp(self):
        patcher_messages = mock.patch('gestioncof.signals.messages')
        patcher_messages.start()
        self.addCleanup(patcher_messages.stop)

        self.factory = RequestFactory()

        user1_acc = Account(trigramme='000')
        user1_acc.change_pwd('kfet_user1')
        user1_acc.save({'username': 'user1'})
        self.user1 = user1_acc.user
        self.user1.set_password('user1')
        self.user1.save()

        user2_acc = Account(trigramme='100')
        user2_acc.change_pwd('kfet_user2')
        user2_acc.save({'username': 'user2'})
        self.user2 = user2_acc.user
        self.user2.set_password('user2')
        self.user2.save()

        self.perm = Permission.objects.get(
            content_type__app_label='kfet', codename='is_team')
        self.user2.user_permissions.add(self.perm)

    def test_middleware_header(self):
        """
        A user can be authenticated if ``HTTP_KFETPASSWORD`` header of a
        request contains a valid kfet password.
        """
        request = self.factory.get('/', HTTP_KFETPASSWORD='kfet_user2')
        request.user = self.user1

        TemporaryAuthMiddleware().process_request(request)

        self.assertEqual(request.user, self.user2)
        self.assertEqual(request.real_user, self.user1)

    def test_middleware_post(self):
        """
        A user can be authenticated if ``KFETPASSWORD`` of POST data contains
        a valid kfet password.
        """
        request = self.factory.post('/', {'KFETPASSWORD': 'kfet_user2'})
        request.user = self.user1

        TemporaryAuthMiddleware().process_request(request)

        self.assertEqual(request.user, self.user2)
        self.assertEqual(request.real_user, self.user1)

    def test_middleware_invalid(self):
        """
        The given password must be a password of an Account.
        """
        request = self.factory.post('/', {'KFETPASSWORD': 'invalid'})
        request.user = self.user1

        TemporaryAuthMiddleware().process_request(request)

        self.assertEqual(request.user, self.user1)
        self.assertFalse(hasattr(request, 'real_user'))

    def test_context_processor(self):
        """
        Context variables give the real authenticated user and his permissions.
        """
        self.client.login(username='user1', password='user1')

        r = self.client.get('/k-fet/accounts/', HTTP_KFETPASSWORD='kfet_user2')

        self.assertEqual(r.context['user'], self.user1)
        self.assertNotIn('kfet.is_team', r.context['perms'])

    def test_auth_not_persistent(self):
        """
        The authentication is temporary, i.e. for one request.
        """
        self.client.login(username='user1', password='user1')

        r1 = self.client.get(
            '/k-fet/accounts/', HTTP_KFETPASSWORD='kfet_user2')
        self.assertEqual(r1.wsgi_request.user, self.user2)

        r2 = self.client.get('/k-fet/accounts/')
        self.assertEqual(r2.wsgi_request.user, self.user1)