# from __future__ import unicode_literals
# from django.db import models
# from django.test import TestCase
# from rest_framework import serializers

# from .models import OneToOneTarget


# class OneToOneSource(models.Model):
#     name = models.CharField(max_length=100)
#     target = models.OneToOneField(OneToOneTarget, related_name='source',
#                                   null=True, blank=True)


# class OneToManyTarget(models.Model):
#     name = models.CharField(max_length=100)


# class OneToManySource(models.Model):
#     name = models.CharField(max_length=100)
#     target = models.ForeignKey(OneToManyTarget, related_name='sources')


# class ReverseNestedOneToOneTests(TestCase):
#     def setUp(self):
#         class OneToOneSourceSerializer(serializers.ModelSerializer):
#             class Meta:
#                 model = OneToOneSource
#                 fields = ('id', 'name')

#         class OneToOneTargetSerializer(serializers.ModelSerializer):
#             source = OneToOneSourceSerializer()

#             class Meta:
#                 model = OneToOneTarget
#                 fields = ('id', 'name', 'source')

#         self.Serializer = OneToOneTargetSerializer

#         for idx in range(1, 4):
#             target = OneToOneTarget(name='target-%d' % idx)
#             target.save()
#             source = OneToOneSource(name='source-%d' % idx, target=target)
#             source.save()

#     def test_one_to_one_retrieve(self):
#         queryset = OneToOneTarget.objects.all()
#         serializer = self.Serializer(queryset, many=True)
#         expected = [
#             {'id': 1, 'name': 'target-1', 'source': {'id': 1, 'name': 'source-1'}},
#             {'id': 2, 'name': 'target-2', 'source': {'id': 2, 'name': 'source-2'}},
#             {'id': 3, 'name': 'target-3', 'source': {'id': 3, 'name': 'source-3'}}
#         ]
#         self.assertEqual(serializer.data, expected)

#     def test_one_to_one_create(self):
#         data = {'id': 4, 'name': 'target-4', 'source': {'id': 4, 'name': 'source-4'}}
#         serializer = self.Serializer(data=data)
#         self.assertTrue(serializer.is_valid())
#         obj = serializer.save()
#         self.assertEqual(serializer.data, data)
#         self.assertEqual(obj.name, 'target-4')

#         # Ensure (target 4, target_source 4, source 4) are added, and
#         # everything else is as expected.
#         queryset = OneToOneTarget.objects.all()
#         serializer = self.Serializer(queryset, many=True)
#         expected = [
#             {'id': 1, 'name': 'target-1', 'source': {'id': 1, 'name': 'source-1'}},
#             {'id': 2, 'name': 'target-2', 'source': {'id': 2, 'name': 'source-2'}},
#             {'id': 3, 'name': 'target-3', 'source': {'id': 3, 'name': 'source-3'}},
#             {'id': 4, 'name': 'target-4', 'source': {'id': 4, 'name': 'source-4'}}
#         ]
#         self.assertEqual(serializer.data, expected)

#     def test_one_to_one_create_with_invalid_data(self):
#         data = {'id': 4, 'name': 'target-4', 'source': {'id': 4}}
#         serializer = self.Serializer(data=data)
#         self.assertFalse(serializer.is_valid())
#         self.assertEqual(serializer.errors, {'source': [{'name': ['This field is required.']}]})

#     def test_one_to_one_update(self):
#         data = {'id': 3, 'name': 'target-3-updated', 'source': {'id': 3, 'name': 'source-3-updated'}}
#         instance = OneToOneTarget.objects.get(pk=3)
#         serializer = self.Serializer(instance, data=data)
#         self.assertTrue(serializer.is_valid())
#         obj = serializer.save()
#         self.assertEqual(serializer.data, data)
#         self.assertEqual(obj.name, 'target-3-updated')

#         # Ensure (target 3, target_source 3, source 3) are updated,
#         # and everything else is as expected.
#         queryset = OneToOneTarget.objects.all()
#         serializer = self.Serializer(queryset, many=True)
#         expected = [
#             {'id': 1, 'name': 'target-1', 'source': {'id': 1, 'name': 'source-1'}},
#             {'id': 2, 'name': 'target-2', 'source': {'id': 2, 'name': 'source-2'}},
#             {'id': 3, 'name': 'target-3-updated', 'source': {'id': 3, 'name': 'source-3-updated'}}
#         ]
#         self.assertEqual(serializer.data, expected)


# class ForwardNestedOneToOneTests(TestCase):
#     def setUp(self):
#         class OneToOneTargetSerializer(serializers.ModelSerializer):
#             class Meta:
#                 model = OneToOneTarget
#                 fields = ('id', 'name')

#         class OneToOneSourceSerializer(serializers.ModelSerializer):
#             target = OneToOneTargetSerializer()

#             class Meta:
#                 model = OneToOneSource
#                 fields = ('id', 'name', 'target')

#         self.Serializer = OneToOneSourceSerializer

#         for idx in range(1, 4):
#             target = OneToOneTarget(name='target-%d' % idx)
#             target.save()
#             source = OneToOneSource(name='source-%d' % idx, target=target)
#             source.save()

#     def test_one_to_one_retrieve(self):
#         queryset = OneToOneSource.objects.all()
#         serializer = self.Serializer(queryset, many=True)
#         expected = [
#             {'id': 1, 'name': 'source-1', 'target': {'id': 1, 'name': 'target-1'}},
#             {'id': 2, 'name': 'source-2', 'target': {'id': 2, 'name': 'target-2'}},
#             {'id': 3, 'name': 'source-3', 'target': {'id': 3, 'name': 'target-3'}}
#         ]
#         self.assertEqual(serializer.data, expected)

#     def test_one_to_one_create(self):
#         data = {'id': 4, 'name': 'source-4', 'target': {'id': 4, 'name': 'target-4'}}
#         serializer = self.Serializer(data=data)
#         self.assertTrue(serializer.is_valid())
#         obj = serializer.save()
#         self.assertEqual(serializer.data, data)
#         self.assertEqual(obj.name, 'source-4')

#         # Ensure (target 4, target_source 4, source 4) are added, and
#         # everything else is as expected.
#         queryset = OneToOneSource.objects.all()
#         serializer = self.Serializer(queryset, many=True)
#         expected = [
#             {'id': 1, 'name': 'source-1', 'target': {'id': 1, 'name': 'target-1'}},
#             {'id': 2, 'name': 'source-2', 'target': {'id': 2, 'name': 'target-2'}},
#             {'id': 3, 'name': 'source-3', 'target': {'id': 3, 'name': 'target-3'}},
#             {'id': 4, 'name': 'source-4', 'target': {'id': 4, 'name': 'target-4'}}
#         ]
#         self.assertEqual(serializer.data, expected)

#     def test_one_to_one_create_with_invalid_data(self):
#         data = {'id': 4, 'name': 'source-4', 'target': {'id': 4}}
#         serializer = self.Serializer(data=data)
#         self.assertFalse(serializer.is_valid())
#         self.assertEqual(serializer.errors, {'target': [{'name': ['This field is required.']}]})

#     def test_one_to_one_update(self):
#         data = {'id': 3, 'name': 'source-3-updated', 'target': {'id': 3, 'name': 'target-3-updated'}}
#         instance = OneToOneSource.objects.get(pk=3)
#         serializer = self.Serializer(instance, data=data)
#         self.assertTrue(serializer.is_valid())
#         obj = serializer.save()
#         self.assertEqual(serializer.data, data)
#         self.assertEqual(obj.name, 'source-3-updated')

#         # Ensure (target 3, target_source 3, source 3) are updated,
#         # and everything else is as expected.
#         queryset = OneToOneSource.objects.all()
#         serializer = self.Serializer(queryset, many=True)
#         expected = [
#             {'id': 1, 'name': 'source-1', 'target': {'id': 1, 'name': 'target-1'}},
#             {'id': 2, 'name': 'source-2', 'target': {'id': 2, 'name': 'target-2'}},
#             {'id': 3, 'name': 'source-3-updated', 'target': {'id': 3, 'name': 'target-3-updated'}}
#         ]
#         self.assertEqual(serializer.data, expected)

#     def test_one_to_one_update_to_null(self):
#         data = {'id': 3, 'name': 'source-3-updated', 'target': None}
#         instance = OneToOneSource.objects.get(pk=3)
#         serializer = self.Serializer(instance, data=data)
#         self.assertTrue(serializer.is_valid())
#         obj = serializer.save()

#         self.assertEqual(serializer.data, data)
#         self.assertEqual(obj.name, 'source-3-updated')
#         self.assertEqual(obj.target, None)

#         queryset = OneToOneSource.objects.all()
#         serializer = self.Serializer(queryset, many=True)
#         expected = [
#             {'id': 1, 'name': 'source-1', 'target': {'id': 1, 'name': 'target-1'}},
#             {'id': 2, 'name': 'source-2', 'target': {'id': 2, 'name': 'target-2'}},
#             {'id': 3, 'name': 'source-3-updated', 'target': None}
#         ]
#         self.assertEqual(serializer.data, expected)

#     # TODO: Nullable 1-1 tests
#     # def test_one_to_one_delete(self):
#     #     data = {'id': 3, 'name': 'target-3', 'target_source': None}
#     #     instance = OneToOneTarget.objects.get(pk=3)
#     #     serializer = self.Serializer(instance, data=data)
#     #     self.assertTrue(serializer.is_valid())
#     #     serializer.save()

#     #     # Ensure (target_source 3, source 3) are deleted,
#     #     # and everything else is as expected.
#     #     queryset = OneToOneTarget.objects.all()
#     #     serializer = self.Serializer(queryset)
#     #     expected = [
#     #         {'id': 1, 'name': 'target-1', 'source': {'id': 1, 'name': 'source-1'}},
#     #         {'id': 2, 'name': 'target-2', 'source': {'id': 2, 'name': 'source-2'}},
#     #         {'id': 3, 'name': 'target-3', 'source': None}
#     #     ]
#     #     self.assertEqual(serializer.data, expected)


# class ReverseNestedOneToManyTests(TestCase):
#     def setUp(self):
#         class OneToManySourceSerializer(serializers.ModelSerializer):
#             class Meta:
#                 model = OneToManySource
#                 fields = ('id', 'name')

#         class OneToManyTargetSerializer(serializers.ModelSerializer):
#             sources = OneToManySourceSerializer(many=True, allow_add_remove=True)

#             class Meta:
#                 model = OneToManyTarget
#                 fields = ('id', 'name', 'sources')

#         self.Serializer = OneToManyTargetSerializer

#         target = OneToManyTarget(name='target-1')
#         target.save()
#         for idx in range(1, 4):
#             source = OneToManySource(name='source-%d' % idx, target=target)
#             source.save()

#     def test_one_to_many_retrieve(self):
#         queryset = OneToManyTarget.objects.all()
#         serializer = self.Serializer(queryset, many=True)
#         expected = [
#             {'id': 1, 'name': 'target-1', 'sources': [{'id': 1, 'name': 'source-1'},
#                                                       {'id': 2, 'name': 'source-2'},
#                                                       {'id': 3, 'name': 'source-3'}]},
#         ]
#         self.assertEqual(serializer.data, expected)

#     def test_one_to_many_create(self):
#         data = {'id': 1, 'name': 'target-1', 'sources': [{'id': 1, 'name': 'source-1'},
#                                                          {'id': 2, 'name': 'source-2'},
#                                                          {'id': 3, 'name': 'source-3'},
#                                                          {'id': 4, 'name': 'source-4'}]}
#         instance = OneToManyTarget.objects.get(pk=1)
#         serializer = self.Serializer(instance, data=data)
#         self.assertTrue(serializer.is_valid())
#         obj = serializer.save()
#         self.assertEqual(serializer.data, data)
#         self.assertEqual(obj.name, 'target-1')

#         # Ensure source 4 is added, and everything else is as
#         # expected.
#         queryset = OneToManyTarget.objects.all()
#         serializer = self.Serializer(queryset, many=True)
#         expected = [
#             {'id': 1, 'name': 'target-1', 'sources': [{'id': 1, 'name': 'source-1'},
#                                                       {'id': 2, 'name': 'source-2'},
#                                                       {'id': 3, 'name': 'source-3'},
#                                                       {'id': 4, 'name': 'source-4'}]}
#         ]
#         self.assertEqual(serializer.data, expected)

#     def test_one_to_many_create_with_invalid_data(self):
#         data = {'id': 1, 'name': 'target-1', 'sources': [{'id': 1, 'name': 'source-1'},
#                                                          {'id': 2, 'name': 'source-2'},
#                                                          {'id': 3, 'name': 'source-3'},
#                                                          {'id': 4}]}
#         serializer = self.Serializer(data=data)
#         self.assertFalse(serializer.is_valid())
#         self.assertEqual(serializer.errors, {'sources': [{}, {}, {}, {'name': ['This field is required.']}]})

#     def test_one_to_many_update(self):
#         data = {'id': 1, 'name': 'target-1-updated', 'sources': [{'id': 1, 'name': 'source-1-updated'},
#                                                                  {'id': 2, 'name': 'source-2'},
#                                                                  {'id': 3, 'name': 'source-3'}]}
#         instance = OneToManyTarget.objects.get(pk=1)
#         serializer = self.Serializer(instance, data=data)
#         self.assertTrue(serializer.is_valid())
#         obj = serializer.save()
#         self.assertEqual(serializer.data, data)
#         self.assertEqual(obj.name, 'target-1-updated')

#         # Ensure (target 1, source 1) are updated,
#         # and everything else is as expected.
#         queryset = OneToManyTarget.objects.all()
#         serializer = self.Serializer(queryset, many=True)
#         expected = [
#             {'id': 1, 'name': 'target-1-updated', 'sources': [{'id': 1, 'name': 'source-1-updated'},
#                                                               {'id': 2, 'name': 'source-2'},
#                                                               {'id': 3, 'name': 'source-3'}]}

#         ]
#         self.assertEqual(serializer.data, expected)

#     def test_one_to_many_delete(self):
#         data = {'id': 1, 'name': 'target-1', 'sources': [{'id': 1, 'name': 'source-1'},
#                                                          {'id': 3, 'name': 'source-3'}]}
#         instance = OneToManyTarget.objects.get(pk=1)
#         serializer = self.Serializer(instance, data=data)
#         self.assertTrue(serializer.is_valid())
#         serializer.save()

#         # Ensure source 2 is deleted, and everything else is as
#         # expected.
#         queryset = OneToManyTarget.objects.all()
#         serializer = self.Serializer(queryset, many=True)
#         expected = [
#             {'id': 1, 'name': 'target-1', 'sources': [{'id': 1, 'name': 'source-1'},
#                                                       {'id': 3, 'name': 'source-3'}]}

#         ]
#         self.assertEqual(serializer.data, expected)