import unittest

from migrations.test_base import OperationTestBase

from django.db import IntegrityError, NotSupportedError, connection, transaction
from django.db.migrations.state import ProjectState
from django.db.models import CheckConstraint, Index, Q, UniqueConstraint
from django.db.utils import ProgrammingError
from django.test import modify_settings, override_settings
from django.test.utils import CaptureQueriesContext

from . import PostgreSQLTestCase

try:
    from django.contrib.postgres.indexes import BrinIndex, BTreeIndex
    from django.contrib.postgres.operations import (
        AddConstraintNotValid,
        AddIndexConcurrently,
        BloomExtension,
        CreateCollation,
        CreateExtension,
        RemoveCollation,
        RemoveIndexConcurrently,
        ValidateConstraint,
    )
except ImportError:
    pass


@unittest.skipUnless(connection.vendor == "postgresql", "PostgreSQL specific tests.")
@modify_settings(INSTALLED_APPS={"append": "migrations"})
class AddIndexConcurrentlyTests(OperationTestBase):
    app_label = "test_add_concurrently"

    def test_requires_atomic_false(self):
        project_state = self.set_up_test_model(self.app_label)
        new_state = project_state.clone()
        operation = AddIndexConcurrently(
            "Pony",
            Index(fields=["pink"], name="pony_pink_idx"),
        )
        msg = (
            "The AddIndexConcurrently operation cannot be executed inside "
            "a transaction (set atomic = False on the migration)."
        )
        with self.assertRaisesMessage(NotSupportedError, msg):
            with connection.schema_editor(atomic=True) as editor:
                operation.database_forwards(
                    self.app_label, editor, project_state, new_state
                )

    def test_add(self):
        project_state = self.set_up_test_model(self.app_label, index=False)
        table_name = "%s_pony" % self.app_label
        index = Index(fields=["pink"], name="pony_pink_idx")
        new_state = project_state.clone()
        operation = AddIndexConcurrently("Pony", index)
        self.assertEqual(
            operation.describe(),
            "Concurrently create index pony_pink_idx on field(s) pink of model Pony",
        )
        operation.state_forwards(self.app_label, new_state)
        self.assertEqual(
            len(new_state.models[self.app_label, "pony"].options["indexes"]), 1
        )
        self.assertIndexNotExists(table_name, ["pink"])
        # Add index.
        with connection.schema_editor(atomic=False) as editor:
            operation.database_forwards(
                self.app_label, editor, project_state, new_state
            )
        self.assertIndexExists(table_name, ["pink"])
        # Reversal.
        with connection.schema_editor(atomic=False) as editor:
            operation.database_backwards(
                self.app_label, editor, new_state, project_state
            )
        self.assertIndexNotExists(table_name, ["pink"])
        # Deconstruction.
        name, args, kwargs = operation.deconstruct()
        self.assertEqual(name, "AddIndexConcurrently")
        self.assertEqual(args, [])
        self.assertEqual(kwargs, {"model_name": "Pony", "index": index})

    def test_add_other_index_type(self):
        project_state = self.set_up_test_model(self.app_label, index=False)
        table_name = "%s_pony" % self.app_label
        new_state = project_state.clone()
        operation = AddIndexConcurrently(
            "Pony",
            BrinIndex(fields=["pink"], name="pony_pink_brin_idx"),
        )
        self.assertIndexNotExists(table_name, ["pink"])
        # Add index.
        with connection.schema_editor(atomic=False) as editor:
            operation.database_forwards(
                self.app_label, editor, project_state, new_state
            )
        self.assertIndexExists(table_name, ["pink"], index_type="brin")
        # Reversal.
        with connection.schema_editor(atomic=False) as editor:
            operation.database_backwards(
                self.app_label, editor, new_state, project_state
            )
        self.assertIndexNotExists(table_name, ["pink"])

    def test_add_with_options(self):
        project_state = self.set_up_test_model(self.app_label, index=False)
        table_name = "%s_pony" % self.app_label
        new_state = project_state.clone()
        index = BTreeIndex(fields=["pink"], name="pony_pink_btree_idx", fillfactor=70)
        operation = AddIndexConcurrently("Pony", index)
        self.assertIndexNotExists(table_name, ["pink"])
        # Add index.
        with connection.schema_editor(atomic=False) as editor:
            operation.database_forwards(
                self.app_label, editor, project_state, new_state
            )
        self.assertIndexExists(table_name, ["pink"], index_type="btree")
        # Reversal.
        with connection.schema_editor(atomic=False) as editor:
            operation.database_backwards(
                self.app_label, editor, new_state, project_state
            )
        self.assertIndexNotExists(table_name, ["pink"])


@unittest.skipUnless(connection.vendor == "postgresql", "PostgreSQL specific tests.")
@modify_settings(INSTALLED_APPS={"append": "migrations"})
class RemoveIndexConcurrentlyTests(OperationTestBase):
    app_label = "test_rm_concurrently"

    def test_requires_atomic_false(self):
        project_state = self.set_up_test_model(self.app_label, index=True)
        new_state = project_state.clone()
        operation = RemoveIndexConcurrently("Pony", "pony_pink_idx")
        msg = (
            "The RemoveIndexConcurrently operation cannot be executed inside "
            "a transaction (set atomic = False on the migration)."
        )
        with self.assertRaisesMessage(NotSupportedError, msg):
            with connection.schema_editor(atomic=True) as editor:
                operation.database_forwards(
                    self.app_label, editor, project_state, new_state
                )

    def test_remove(self):
        project_state = self.set_up_test_model(self.app_label, index=True)
        table_name = "%s_pony" % self.app_label
        self.assertTableExists(table_name)
        new_state = project_state.clone()
        operation = RemoveIndexConcurrently("Pony", "pony_pink_idx")
        self.assertEqual(
            operation.describe(),
            "Concurrently remove index pony_pink_idx from Pony",
        )
        operation.state_forwards(self.app_label, new_state)
        self.assertEqual(
            len(new_state.models[self.app_label, "pony"].options["indexes"]), 0
        )
        self.assertIndexExists(table_name, ["pink"])
        # Remove index.
        with connection.schema_editor(atomic=False) as editor:
            operation.database_forwards(
                self.app_label, editor, project_state, new_state
            )
        self.assertIndexNotExists(table_name, ["pink"])
        # Reversal.
        with connection.schema_editor(atomic=False) as editor:
            operation.database_backwards(
                self.app_label, editor, new_state, project_state
            )
        self.assertIndexExists(table_name, ["pink"])
        # Deconstruction.
        name, args, kwargs = operation.deconstruct()
        self.assertEqual(name, "RemoveIndexConcurrently")
        self.assertEqual(args, [])
        self.assertEqual(kwargs, {"model_name": "Pony", "name": "pony_pink_idx"})


class NoMigrationRouter:
    def allow_migrate(self, db, app_label, **hints):
        return False


@unittest.skipUnless(connection.vendor == "postgresql", "PostgreSQL specific tests.")
class CreateExtensionTests(PostgreSQLTestCase):
    app_label = "test_allow_create_extention"

    @override_settings(DATABASE_ROUTERS=[NoMigrationRouter()])
    def test_no_allow_migrate(self):
        operation = CreateExtension("tablefunc")
        project_state = ProjectState()
        new_state = project_state.clone()
        # Don't create an extension.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_forwards(
                    self.app_label, editor, project_state, new_state
                )
        self.assertEqual(len(captured_queries), 0)
        # Reversal.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_backwards(
                    self.app_label, editor, new_state, project_state
                )
        self.assertEqual(len(captured_queries), 0)

    def test_allow_migrate(self):
        operation = CreateExtension("tablefunc")
        self.assertEqual(
            operation.migration_name_fragment, "create_extension_tablefunc"
        )
        project_state = ProjectState()
        new_state = project_state.clone()
        # Create an extension.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_forwards(
                    self.app_label, editor, project_state, new_state
                )
        self.assertEqual(len(captured_queries), 4)
        self.assertIn("CREATE EXTENSION IF NOT EXISTS", captured_queries[1]["sql"])
        # Reversal.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_backwards(
                    self.app_label, editor, new_state, project_state
                )
        self.assertEqual(len(captured_queries), 2)
        self.assertIn("DROP EXTENSION IF EXISTS", captured_queries[1]["sql"])

    def test_create_existing_extension(self):
        operation = BloomExtension()
        self.assertEqual(operation.migration_name_fragment, "create_extension_bloom")
        project_state = ProjectState()
        new_state = project_state.clone()
        # Don't create an existing extension.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_forwards(
                    self.app_label, editor, project_state, new_state
                )
        self.assertEqual(len(captured_queries), 3)
        self.assertIn("SELECT", captured_queries[0]["sql"])

    def test_drop_nonexistent_extension(self):
        operation = CreateExtension("tablefunc")
        project_state = ProjectState()
        new_state = project_state.clone()
        # Don't drop a nonexistent extension.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_backwards(
                    self.app_label, editor, project_state, new_state
                )
        self.assertEqual(len(captured_queries), 1)
        self.assertIn("SELECT", captured_queries[0]["sql"])


@unittest.skipUnless(connection.vendor == "postgresql", "PostgreSQL specific tests.")
class CreateCollationTests(PostgreSQLTestCase):
    app_label = "test_allow_create_collation"

    @override_settings(DATABASE_ROUTERS=[NoMigrationRouter()])
    def test_no_allow_migrate(self):
        operation = CreateCollation("C_test", locale="C")
        project_state = ProjectState()
        new_state = project_state.clone()
        # Don't create a collation.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_forwards(
                    self.app_label, editor, project_state, new_state
                )
        self.assertEqual(len(captured_queries), 0)
        # Reversal.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_backwards(
                    self.app_label, editor, new_state, project_state
                )
        self.assertEqual(len(captured_queries), 0)

    def test_create(self):
        operation = CreateCollation("C_test", locale="C")
        self.assertEqual(operation.migration_name_fragment, "create_collation_c_test")
        self.assertEqual(operation.describe(), "Create collation C_test")
        project_state = ProjectState()
        new_state = project_state.clone()
        # Create a collation.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_forwards(
                    self.app_label, editor, project_state, new_state
                )
        self.assertEqual(len(captured_queries), 1)
        self.assertIn("CREATE COLLATION", captured_queries[0]["sql"])
        # Creating the same collation raises an exception.
        with self.assertRaisesMessage(ProgrammingError, "already exists"):
            with connection.schema_editor(atomic=True) as editor:
                operation.database_forwards(
                    self.app_label, editor, project_state, new_state
                )
        # Reversal.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_backwards(
                    self.app_label, editor, new_state, project_state
                )
        self.assertEqual(len(captured_queries), 1)
        self.assertIn("DROP COLLATION", captured_queries[0]["sql"])
        # Deconstruction.
        name, args, kwargs = operation.deconstruct()
        self.assertEqual(name, "CreateCollation")
        self.assertEqual(args, [])
        self.assertEqual(kwargs, {"name": "C_test", "locale": "C"})

    def test_create_non_deterministic_collation(self):
        operation = CreateCollation(
            "case_insensitive_test",
            "und-u-ks-level2",
            provider="icu",
            deterministic=False,
        )
        project_state = ProjectState()
        new_state = project_state.clone()
        # Create a collation.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_forwards(
                    self.app_label, editor, project_state, new_state
                )
        self.assertEqual(len(captured_queries), 1)
        self.assertIn("CREATE COLLATION", captured_queries[0]["sql"])
        # Reversal.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_backwards(
                    self.app_label, editor, new_state, project_state
                )
        self.assertEqual(len(captured_queries), 1)
        self.assertIn("DROP COLLATION", captured_queries[0]["sql"])
        # Deconstruction.
        name, args, kwargs = operation.deconstruct()
        self.assertEqual(name, "CreateCollation")
        self.assertEqual(args, [])
        self.assertEqual(
            kwargs,
            {
                "name": "case_insensitive_test",
                "locale": "und-u-ks-level2",
                "provider": "icu",
                "deterministic": False,
            },
        )

    def test_create_collation_alternate_provider(self):
        operation = CreateCollation(
            "german_phonebook_test",
            provider="icu",
            locale="de-u-co-phonebk",
        )
        project_state = ProjectState()
        new_state = project_state.clone()
        # Create an collation.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_forwards(
                    self.app_label, editor, project_state, new_state
                )
        self.assertEqual(len(captured_queries), 1)
        self.assertIn("CREATE COLLATION", captured_queries[0]["sql"])
        # Reversal.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_backwards(
                    self.app_label, editor, new_state, project_state
                )
        self.assertEqual(len(captured_queries), 1)
        self.assertIn("DROP COLLATION", captured_queries[0]["sql"])


@unittest.skipUnless(connection.vendor == "postgresql", "PostgreSQL specific tests.")
class RemoveCollationTests(PostgreSQLTestCase):
    app_label = "test_allow_remove_collation"

    @override_settings(DATABASE_ROUTERS=[NoMigrationRouter()])
    def test_no_allow_migrate(self):
        operation = RemoveCollation("C_test", locale="C")
        project_state = ProjectState()
        new_state = project_state.clone()
        # Don't create a collation.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_forwards(
                    self.app_label, editor, project_state, new_state
                )
        self.assertEqual(len(captured_queries), 0)
        # Reversal.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_backwards(
                    self.app_label, editor, new_state, project_state
                )
        self.assertEqual(len(captured_queries), 0)

    def test_remove(self):
        operation = CreateCollation("C_test", locale="C")
        project_state = ProjectState()
        new_state = project_state.clone()
        with connection.schema_editor(atomic=False) as editor:
            operation.database_forwards(
                self.app_label, editor, project_state, new_state
            )

        operation = RemoveCollation("C_test", locale="C")
        self.assertEqual(operation.migration_name_fragment, "remove_collation_c_test")
        self.assertEqual(operation.describe(), "Remove collation C_test")
        project_state = ProjectState()
        new_state = project_state.clone()
        # Remove a collation.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_forwards(
                    self.app_label, editor, project_state, new_state
                )
        self.assertEqual(len(captured_queries), 1)
        self.assertIn("DROP COLLATION", captured_queries[0]["sql"])
        # Removing a nonexistent collation raises an exception.
        with self.assertRaisesMessage(ProgrammingError, "does not exist"):
            with connection.schema_editor(atomic=True) as editor:
                operation.database_forwards(
                    self.app_label, editor, project_state, new_state
                )
        # Reversal.
        with CaptureQueriesContext(connection) as captured_queries:
            with connection.schema_editor(atomic=False) as editor:
                operation.database_backwards(
                    self.app_label, editor, new_state, project_state
                )
        self.assertEqual(len(captured_queries), 1)
        self.assertIn("CREATE COLLATION", captured_queries[0]["sql"])
        # Deconstruction.
        name, args, kwargs = operation.deconstruct()
        self.assertEqual(name, "RemoveCollation")
        self.assertEqual(args, [])
        self.assertEqual(kwargs, {"name": "C_test", "locale": "C"})


@unittest.skipUnless(connection.vendor == "postgresql", "PostgreSQL specific tests.")
@modify_settings(INSTALLED_APPS={"append": "migrations"})
class AddConstraintNotValidTests(OperationTestBase):
    app_label = "test_add_constraint_not_valid"

    def test_non_check_constraint_not_supported(self):
        constraint = UniqueConstraint(fields=["pink"], name="pony_pink_uniq")
        msg = "AddConstraintNotValid.constraint must be a check constraint."
        with self.assertRaisesMessage(TypeError, msg):
            AddConstraintNotValid(model_name="pony", constraint=constraint)

    def test_add(self):
        table_name = f"{self.app_label}_pony"
        constraint_name = "pony_pink_gte_check"
        constraint = CheckConstraint(check=Q(pink__gte=4), name=constraint_name)
        operation = AddConstraintNotValid("Pony", constraint=constraint)
        project_state, new_state = self.make_test_state(self.app_label, operation)
        self.assertEqual(
            operation.describe(),
            f"Create not valid constraint {constraint_name} on model Pony",
        )
        self.assertEqual(
            operation.migration_name_fragment,
            f"pony_{constraint_name}_not_valid",
        )
        self.assertEqual(
            len(new_state.models[self.app_label, "pony"].options["constraints"]),
            1,
        )
        self.assertConstraintNotExists(table_name, constraint_name)
        Pony = new_state.apps.get_model(self.app_label, "Pony")
        self.assertEqual(len(Pony._meta.constraints), 1)
        Pony.objects.create(pink=2, weight=1.0)
        # Add constraint.
        with connection.schema_editor(atomic=True) as editor:
            operation.database_forwards(
                self.app_label, editor, project_state, new_state
            )
        msg = f'check constraint "{constraint_name}"'
        with self.assertRaisesMessage(IntegrityError, msg), transaction.atomic():
            Pony.objects.create(pink=3, weight=1.0)
        self.assertConstraintExists(table_name, constraint_name)
        # Reversal.
        with connection.schema_editor(atomic=True) as editor:
            operation.database_backwards(
                self.app_label, editor, project_state, new_state
            )
        self.assertConstraintNotExists(table_name, constraint_name)
        Pony.objects.create(pink=3, weight=1.0)
        # Deconstruction.
        name, args, kwargs = operation.deconstruct()
        self.assertEqual(name, "AddConstraintNotValid")
        self.assertEqual(args, [])
        self.assertEqual(kwargs, {"model_name": "Pony", "constraint": constraint})


@unittest.skipUnless(connection.vendor == "postgresql", "PostgreSQL specific tests.")
@modify_settings(INSTALLED_APPS={"append": "migrations"})
class ValidateConstraintTests(OperationTestBase):
    app_label = "test_validate_constraint"

    def test_validate(self):
        constraint_name = "pony_pink_gte_check"
        constraint = CheckConstraint(check=Q(pink__gte=4), name=constraint_name)
        operation = AddConstraintNotValid("Pony", constraint=constraint)
        project_state, new_state = self.make_test_state(self.app_label, operation)
        Pony = new_state.apps.get_model(self.app_label, "Pony")
        obj = Pony.objects.create(pink=2, weight=1.0)
        # Add constraint.
        with connection.schema_editor(atomic=True) as editor:
            operation.database_forwards(
                self.app_label, editor, project_state, new_state
            )
        project_state = new_state
        new_state = new_state.clone()
        operation = ValidateConstraint("Pony", name=constraint_name)
        operation.state_forwards(self.app_label, new_state)
        self.assertEqual(
            operation.describe(),
            f"Validate constraint {constraint_name} on model Pony",
        )
        self.assertEqual(
            operation.migration_name_fragment,
            f"pony_validate_{constraint_name}",
        )
        # Validate constraint.
        with connection.schema_editor(atomic=True) as editor:
            msg = f'check constraint "{constraint_name}"'
            with self.assertRaisesMessage(IntegrityError, msg):
                operation.database_forwards(
                    self.app_label, editor, project_state, new_state
                )
        obj.pink = 5
        obj.save()
        with connection.schema_editor(atomic=True) as editor:
            operation.database_forwards(
                self.app_label, editor, project_state, new_state
            )
        # Reversal is a noop.
        with connection.schema_editor() as editor:
            with self.assertNumQueries(0):
                operation.database_backwards(
                    self.app_label, editor, new_state, project_state
                )
        # Deconstruction.
        name, args, kwargs = operation.deconstruct()
        self.assertEqual(name, "ValidateConstraint")
        self.assertEqual(args, [])
        self.assertEqual(kwargs, {"model_name": "Pony", "name": constraint_name})
