"""
Tests for django test runner
"""
import unittest
from unittest import mock

from admin_scripts.tests import AdminScriptTestCase

from django import db
from django.conf import settings
from django.core.exceptions import ImproperlyConfigured
from django.core.management import call_command
from django.test import (
    TestCase, TransactionTestCase, skipUnlessDBFeature, testcases,
)
from django.test.runner import DiscoverRunner
from django.test.testcases import connections_support_transactions
from django.test.utils import dependency_ordered

from .models import B, Person, Through


class DependencyOrderingTests(unittest.TestCase):

    def test_simple_dependencies(self):
        raw = [
            ('s1', ('s1_db', ['alpha'])),
            ('s2', ('s2_db', ['bravo'])),
            ('s3', ('s3_db', ['charlie'])),
        ]
        dependencies = {
            'alpha': ['charlie'],
            'bravo': ['charlie'],
        }

        ordered = dependency_ordered(raw, dependencies=dependencies)
        ordered_sigs = [sig for sig, value in ordered]

        self.assertIn('s1', ordered_sigs)
        self.assertIn('s2', ordered_sigs)
        self.assertIn('s3', ordered_sigs)
        self.assertLess(ordered_sigs.index('s3'), ordered_sigs.index('s1'))
        self.assertLess(ordered_sigs.index('s3'), ordered_sigs.index('s2'))

    def test_chained_dependencies(self):
        raw = [
            ('s1', ('s1_db', ['alpha'])),
            ('s2', ('s2_db', ['bravo'])),
            ('s3', ('s3_db', ['charlie'])),
        ]
        dependencies = {
            'alpha': ['bravo'],
            'bravo': ['charlie'],
        }

        ordered = dependency_ordered(raw, dependencies=dependencies)
        ordered_sigs = [sig for sig, value in ordered]

        self.assertIn('s1', ordered_sigs)
        self.assertIn('s2', ordered_sigs)
        self.assertIn('s3', ordered_sigs)

        # Explicit dependencies
        self.assertLess(ordered_sigs.index('s2'), ordered_sigs.index('s1'))
        self.assertLess(ordered_sigs.index('s3'), ordered_sigs.index('s2'))

        # Implied dependencies
        self.assertLess(ordered_sigs.index('s3'), ordered_sigs.index('s1'))

    def test_multiple_dependencies(self):
        raw = [
            ('s1', ('s1_db', ['alpha'])),
            ('s2', ('s2_db', ['bravo'])),
            ('s3', ('s3_db', ['charlie'])),
            ('s4', ('s4_db', ['delta'])),
        ]
        dependencies = {
            'alpha': ['bravo', 'delta'],
            'bravo': ['charlie'],
            'delta': ['charlie'],
        }

        ordered = dependency_ordered(raw, dependencies=dependencies)
        ordered_sigs = [sig for sig, aliases in ordered]

        self.assertIn('s1', ordered_sigs)
        self.assertIn('s2', ordered_sigs)
        self.assertIn('s3', ordered_sigs)
        self.assertIn('s4', ordered_sigs)

        # Explicit dependencies
        self.assertLess(ordered_sigs.index('s2'), ordered_sigs.index('s1'))
        self.assertLess(ordered_sigs.index('s4'), ordered_sigs.index('s1'))
        self.assertLess(ordered_sigs.index('s3'), ordered_sigs.index('s2'))
        self.assertLess(ordered_sigs.index('s3'), ordered_sigs.index('s4'))

        # Implicit dependencies
        self.assertLess(ordered_sigs.index('s3'), ordered_sigs.index('s1'))

    def test_circular_dependencies(self):
        raw = [
            ('s1', ('s1_db', ['alpha'])),
            ('s2', ('s2_db', ['bravo'])),
        ]
        dependencies = {
            'bravo': ['alpha'],
            'alpha': ['bravo'],
        }

        with self.assertRaises(ImproperlyConfigured):
            dependency_ordered(raw, dependencies=dependencies)

    def test_own_alias_dependency(self):
        raw = [
            ('s1', ('s1_db', ['alpha', 'bravo']))
        ]
        dependencies = {
            'alpha': ['bravo']
        }

        with self.assertRaises(ImproperlyConfigured):
            dependency_ordered(raw, dependencies=dependencies)

        # reordering aliases shouldn't matter
        raw = [
            ('s1', ('s1_db', ['bravo', 'alpha']))
        ]

        with self.assertRaises(ImproperlyConfigured):
            dependency_ordered(raw, dependencies=dependencies)


class MockTestRunner:
    def __init__(self, *args, **kwargs):
        pass


MockTestRunner.run_tests = mock.Mock(return_value=[])


class ManageCommandTests(unittest.TestCase):

    def test_custom_test_runner(self):
        call_command('test', 'sites',
                     testrunner='test_runner.tests.MockTestRunner')
        MockTestRunner.run_tests.assert_called_with(('sites',))

    def test_bad_test_runner(self):
        with self.assertRaises(AttributeError):
            call_command('test', 'sites', testrunner='test_runner.NonexistentRunner')


class CustomTestRunnerOptionsTests(AdminScriptTestCase):

    def setUp(self):
        settings = {
            'TEST_RUNNER': '\'test_runner.runner.CustomOptionsTestRunner\'',
        }
        self.write_settings('settings.py', sdict=settings)

    def tearDown(self):
        self.remove_settings('settings.py')

    def test_default_options(self):
        args = ['test', '--settings=test_project.settings']
        out, err = self.run_django_admin(args)
        self.assertNoOutput(err)
        self.assertOutput(out, '1:2:3')

    def test_default_and_given_options(self):
        args = ['test', '--settings=test_project.settings', '--option_b=foo']
        out, err = self.run_django_admin(args)
        self.assertNoOutput(err)
        self.assertOutput(out, '1:foo:3')

    def test_option_name_and_value_separated(self):
        args = ['test', '--settings=test_project.settings', '--option_b', 'foo']
        out, err = self.run_django_admin(args)
        self.assertNoOutput(err)
        self.assertOutput(out, '1:foo:3')

    def test_all_options_given(self):
        args = ['test', '--settings=test_project.settings', '--option_a=bar',
                '--option_b=foo', '--option_c=31337']
        out, err = self.run_django_admin(args)
        self.assertNoOutput(err)
        self.assertOutput(out, 'bar:foo:31337')


class Ticket17477RegressionTests(AdminScriptTestCase):
    def setUp(self):
        self.write_settings('settings.py')

    def tearDown(self):
        self.remove_settings('settings.py')

    def test_ticket_17477(self):
        """'manage.py help test' works after r16352."""
        args = ['help', 'test']
        out, err = self.run_manage(args)
        self.assertNoOutput(err)


class Sqlite3InMemoryTestDbs(TestCase):
    multi_db = True

    @unittest.skipUnless(all(db.connections[conn].vendor == 'sqlite' for conn in db.connections),
                         "This is an sqlite-specific issue")
    def test_transaction_support(self):
        """Ticket #16329: sqlite3 in-memory test databases"""
        for option_key, option_value in (
                ('NAME', ':memory:'), ('TEST', {'NAME': ':memory:'})):
            tested_connections = db.ConnectionHandler({
                'default': {
                    'ENGINE': 'django.db.backends.sqlite3',
                    option_key: option_value,
                },
                'other': {
                    'ENGINE': 'django.db.backends.sqlite3',
                    option_key: option_value,
                },
            })
            with mock.patch('django.db.connections', new=tested_connections):
                with mock.patch('django.test.testcases.connections', new=tested_connections):
                    other = tested_connections['other']
                    DiscoverRunner(verbosity=0).setup_databases()
                    msg = ("DATABASES setting '%s' option set to sqlite3's ':memory:' value "
                           "shouldn't interfere with transaction support detection." % option_key)
                    # Transaction support should be properly initialized for the 'other' DB
                    self.assertTrue(other.features.supports_transactions, msg)
                    # And all the DBs should report that they support transactions
                    self.assertTrue(connections_support_transactions(), msg)


class DummyBackendTest(unittest.TestCase):
    def test_setup_databases(self):
        """
        setup_databases() doesn't fail with dummy database backend.
        """
        tested_connections = db.ConnectionHandler({})
        with mock.patch('django.test.utils.connections', new=tested_connections):
            runner_instance = DiscoverRunner(verbosity=0)
            old_config = runner_instance.setup_databases()
            runner_instance.teardown_databases(old_config)


class AliasedDefaultTestSetupTest(unittest.TestCase):
    def test_setup_aliased_default_database(self):
        """
        setup_datebases() doesn't fail when 'default' is aliased
        """
        tested_connections = db.ConnectionHandler({
            'default': {
                'NAME': 'dummy'
            },
            'aliased': {
                'NAME': 'dummy'
            }
        })
        with mock.patch('django.test.utils.connections', new=tested_connections):
            runner_instance = DiscoverRunner(verbosity=0)
            old_config = runner_instance.setup_databases()
            runner_instance.teardown_databases(old_config)


class SetupDatabasesTests(unittest.TestCase):

    def setUp(self):
        self.runner_instance = DiscoverRunner(verbosity=0)

    def test_setup_aliased_databases(self):
        tested_connections = db.ConnectionHandler({
            'default': {
                'ENGINE': 'django.db.backends.dummy',
                'NAME': 'dbname',
            },
            'other': {
                'ENGINE': 'django.db.backends.dummy',
                'NAME': 'dbname',
            }
        })

        with mock.patch('django.db.backends.dummy.base.DatabaseWrapper.creation_class') as mocked_db_creation:
            with mock.patch('django.test.utils.connections', new=tested_connections):
                old_config = self.runner_instance.setup_databases()
                self.runner_instance.teardown_databases(old_config)
        mocked_db_creation.return_value.destroy_test_db.assert_called_once_with('dbname', 0, False)

    def test_destroy_test_db_restores_db_name(self):
        tested_connections = db.ConnectionHandler({
            'default': {
                'ENGINE': settings.DATABASES[db.DEFAULT_DB_ALIAS]["ENGINE"],
                'NAME': 'xxx_test_database',
            },
        })
        # Using the real current name as old_name to not mess with the test suite.
        old_name = settings.DATABASES[db.DEFAULT_DB_ALIAS]["NAME"]
        with mock.patch('django.db.connections', new=tested_connections):
            tested_connections['default'].creation.destroy_test_db(old_name, verbosity=0, keepdb=True)
            self.assertEqual(tested_connections['default'].settings_dict["NAME"], old_name)

    def test_serialization(self):
        tested_connections = db.ConnectionHandler({
            'default': {
                'ENGINE': 'django.db.backends.dummy',
            },
        })
        with mock.patch('django.db.backends.dummy.base.DatabaseWrapper.creation_class') as mocked_db_creation:
            with mock.patch('django.test.utils.connections', new=tested_connections):
                self.runner_instance.setup_databases()
        mocked_db_creation.return_value.create_test_db.assert_called_once_with(
            verbosity=0, autoclobber=False, serialize=True, keepdb=False
        )

    def test_serialized_off(self):
        tested_connections = db.ConnectionHandler({
            'default': {
                'ENGINE': 'django.db.backends.dummy',
                'TEST': {'SERIALIZE': False},
            },
        })
        with mock.patch('django.db.backends.dummy.base.DatabaseWrapper.creation_class') as mocked_db_creation:
            with mock.patch('django.test.utils.connections', new=tested_connections):
                self.runner_instance.setup_databases()
        mocked_db_creation.return_value.create_test_db.assert_called_once_with(
            verbosity=0, autoclobber=False, serialize=False, keepdb=False
        )


@skipUnlessDBFeature('supports_sequence_reset')
class AutoIncrementResetTest(TransactionTestCase):
    """
    Creating the same models in different test methods receive the same PK
    values since the sequences are reset before each test method.
    """

    available_apps = ['test_runner']

    reset_sequences = True

    def _test(self):
        # Regular model
        p = Person.objects.create(first_name='Jack', last_name='Smith')
        self.assertEqual(p.pk, 1)
        # Many-to-many through model
        b = B.objects.create()
        t = Through.objects.create(person=p, b=b)
        self.assertEqual(t.pk, 1)

    def test_autoincrement_reset1(self):
        self._test()

    def test_autoincrement_reset2(self):
        self._test()


class EmptyDefaultDatabaseTest(unittest.TestCase):
    def test_empty_default_database(self):
        """
        An empty default database in settings does not raise an ImproperlyConfigured
        error when running a unit test that does not use a database.
        """
        testcases.connections = db.ConnectionHandler({'default': {}})
        connection = testcases.connections[db.utils.DEFAULT_DB_ALIAS]
        self.assertEqual(connection.settings_dict['ENGINE'], 'django.db.backends.dummy')
        connections_support_transactions()