from django.core import checks
from django.core.checks import Error
from django.db import models
from django.test import SimpleTestCase, TestCase, skipUnlessDBFeature
from django.test.utils import (
    isolate_apps, modify_settings, override_system_checks,
)


@isolate_apps('check_framework', attr_name='apps')
@override_system_checks([checks.model_checks.check_all_models])
class DuplicateDBTableTests(SimpleTestCase):
    def test_collision_in_same_app(self):
        class Model1(models.Model):
            class Meta:
                db_table = 'test_table'

        class Model2(models.Model):
            class Meta:
                db_table = 'test_table'

        self.assertEqual(checks.run_checks(app_configs=self.apps.get_app_configs()), [
            Error(
                "db_table 'test_table' is used by multiple models: "
                "check_framework.Model1, check_framework.Model2.",
                obj='test_table',
                id='models.E028',
            )
        ])

    @modify_settings(INSTALLED_APPS={'append': 'basic'})
    @isolate_apps('basic', 'check_framework', kwarg_name='apps')
    def test_collision_across_apps(self, apps):
        class Model1(models.Model):
            class Meta:
                app_label = 'basic'
                db_table = 'test_table'

        class Model2(models.Model):
            class Meta:
                app_label = 'check_framework'
                db_table = 'test_table'

        self.assertEqual(checks.run_checks(app_configs=apps.get_app_configs()), [
            Error(
                "db_table 'test_table' is used by multiple models: "
                "basic.Model1, check_framework.Model2.",
                obj='test_table',
                id='models.E028',
            )
        ])

    def test_no_collision_for_unmanaged_models(self):
        class Unmanaged(models.Model):
            class Meta:
                db_table = 'test_table'
                managed = False

        class Managed(models.Model):
            class Meta:
                db_table = 'test_table'

        self.assertEqual(checks.run_checks(app_configs=self.apps.get_app_configs()), [])

    def test_no_collision_for_proxy_models(self):
        class Model(models.Model):
            class Meta:
                db_table = 'test_table'

        class ProxyModel(Model):
            class Meta:
                proxy = True

        self.assertEqual(Model._meta.db_table, ProxyModel._meta.db_table)
        self.assertEqual(checks.run_checks(app_configs=self.apps.get_app_configs()), [])


@isolate_apps('check_framework', attr_name='apps')
@override_system_checks([checks.model_checks.check_all_models])
class IndexNameTests(SimpleTestCase):
    def test_collision_in_same_model(self):
        index = models.Index(fields=['id'], name='foo')

        class Model(models.Model):
            class Meta:
                indexes = [index, index]

        self.assertEqual(checks.run_checks(app_configs=self.apps.get_app_configs()), [
            Error(
                "index name 'foo' is not unique for model check_framework.Model.",
                id='models.E029',
            ),
        ])

    def test_collision_in_different_models(self):
        index = models.Index(fields=['id'], name='foo')

        class Model1(models.Model):
            class Meta:
                indexes = [index]

        class Model2(models.Model):
            class Meta:
                indexes = [index]

        self.assertEqual(checks.run_checks(app_configs=self.apps.get_app_configs()), [
            Error(
                "index name 'foo' is not unique amongst models: "
                "check_framework.Model1, check_framework.Model2.",
                id='models.E030',
            ),
        ])

    def test_collision_abstract_model(self):
        class AbstractModel(models.Model):
            class Meta:
                indexes = [models.Index(fields=['id'], name='foo')]
                abstract = True

        class Model1(AbstractModel):
            pass

        class Model2(AbstractModel):
            pass

        self.assertEqual(checks.run_checks(app_configs=self.apps.get_app_configs()), [
            Error(
                "index name 'foo' is not unique amongst models: "
                "check_framework.Model1, check_framework.Model2.",
                id='models.E030',
            ),
        ])

    @modify_settings(INSTALLED_APPS={'append': 'basic'})
    @isolate_apps('basic', 'check_framework', kwarg_name='apps')
    def test_collision_across_apps(self, apps):
        index = models.Index(fields=['id'], name='foo')

        class Model1(models.Model):
            class Meta:
                app_label = 'basic'
                indexes = [index]

        class Model2(models.Model):
            class Meta:
                app_label = 'check_framework'
                indexes = [index]

        self.assertEqual(checks.run_checks(app_configs=apps.get_app_configs()), [
            Error(
                "index name 'foo' is not unique amongst models: basic.Model1, "
                "check_framework.Model2.",
                id='models.E030',
            ),
        ])


@isolate_apps('check_framework', attr_name='apps')
@override_system_checks([checks.model_checks.check_all_models])
@skipUnlessDBFeature('supports_table_check_constraints')
class ConstraintNameTests(TestCase):
    def test_collision_in_same_model(self):
        class Model(models.Model):
            class Meta:
                constraints = [
                    models.CheckConstraint(check=models.Q(id__gt=0), name='foo'),
                    models.CheckConstraint(check=models.Q(id__lt=100), name='foo'),
                ]

        self.assertEqual(checks.run_checks(app_configs=self.apps.get_app_configs()), [
            Error(
                "constraint name 'foo' is not unique for model "
                "check_framework.Model.",
                id='models.E031',
            ),
        ])

    def test_collision_in_different_models(self):
        constraint = models.CheckConstraint(check=models.Q(id__gt=0), name='foo')

        class Model1(models.Model):
            class Meta:
                constraints = [constraint]

        class Model2(models.Model):
            class Meta:
                constraints = [constraint]

        self.assertEqual(checks.run_checks(app_configs=self.apps.get_app_configs()), [
            Error(
                "constraint name 'foo' is not unique amongst models: "
                "check_framework.Model1, check_framework.Model2.",
                id='models.E032',
            ),
        ])

    def test_collision_abstract_model(self):
        class AbstractModel(models.Model):
            class Meta:
                constraints = [models.CheckConstraint(check=models.Q(id__gt=0), name='foo')]
                abstract = True

        class Model1(AbstractModel):
            pass

        class Model2(AbstractModel):
            pass

        self.assertEqual(checks.run_checks(app_configs=self.apps.get_app_configs()), [
            Error(
                "constraint name 'foo' is not unique amongst models: "
                "check_framework.Model1, check_framework.Model2.",
                id='models.E032',
            ),
        ])

    @modify_settings(INSTALLED_APPS={'append': 'basic'})
    @isolate_apps('basic', 'check_framework', kwarg_name='apps')
    def test_collision_across_apps(self, apps):
        constraint = models.CheckConstraint(check=models.Q(id__gt=0), name='foo')

        class Model1(models.Model):
            class Meta:
                app_label = 'basic'
                constraints = [constraint]

        class Model2(models.Model):
            class Meta:
                app_label = 'check_framework'
                constraints = [constraint]

        self.assertEqual(checks.run_checks(app_configs=apps.get_app_configs()), [
            Error(
                "constraint name 'foo' is not unique amongst models: "
                "basic.Model1, check_framework.Model2.",
                id='models.E032',
            ),
        ])