import datetime
import os
import re
import warnings

from peewee import *
from playhouse.reflection import *

from .base import IS_CRDB
from .base import IS_CYSQLITE
from .base import IS_MYSQL
from .base import IS_POSTGRESQL
from .base import IS_SQLITE
from .base import IS_SQLITE_OLD
from .base import ModelTestCase
from .base import TestModel
from .base import db
from .base import requires_models
from .base import requires_sqlite
from .base import skip_if
from .base_models import Tweet
from .base_models import User


class ColTypes(TestModel):
    f1 = BigIntegerField(index=True)
    f2 = BlobField()
    f3 = BooleanField()
    f4 = CharField(max_length=50)
    f5 = DateField()
    f6 = DateTimeField()
    f7 = DecimalField()
    f8 = DoubleField()
    f9 = FloatField()
    f10 = IntegerField(unique=True)
    f11 = AutoField()
    f12 = TextField()
    f13 = TimeField()

    class Meta:
        indexes = (
            (('f10', 'f11'), True),
            (('f11', 'f8', 'f13'), False),
        )


class Nullable(TestModel):
    nullable_cf = CharField(null=True)
    nullable_if = IntegerField(null=True)


class RelModel(TestModel):
    col_types = ForeignKeyField(ColTypes, backref='foo')
    col_types_nullable = ForeignKeyField(ColTypes, null=True)


class FKPK(TestModel):
    col_types = ForeignKeyField(ColTypes, primary_key=True)


class Underscores(TestModel):
    _id = AutoField()
    _name = CharField()


class Category(TestModel):
    name = CharField(max_length=10)
    parent = ForeignKeyField('self', null=True)


class Nugget(TestModel):
    category_id = ForeignKeyField(Category, column_name='category_id')
    category = CharField()


class NoPK(TestModel):
    data = CharField()
    class Meta:
        primary_key = False


class BaseReflectionTestCase(ModelTestCase):
    def setUp(self):
        super(BaseReflectionTestCase, self).setUp()
        self.introspector = Introspector.from_database(self.database)


class TestReflection(BaseReflectionTestCase):
    requires = [ColTypes, Nullable, RelModel, FKPK, Underscores, Category,
                Nugget]

    def test_generate_models(self):
        models = self.introspector.generate_models()
        self.assertTrue(set((
            'category',
            'col_types',
            'fkpk',
            'nugget',
            'nullable',
            'rel_model',
            'underscores')).issubset(set(models)))

        def assertIsInstance(obj, klass):
            self.assertTrue(isinstance(obj, klass))

        category = models['category']
        self.assertEqual(
            sorted(category._meta.fields),
            ['id', 'name', 'parent'])
        assertIsInstance(category.id, AutoField)
        assertIsInstance(category.name, CharField)
        assertIsInstance(category.parent, ForeignKeyField)
        self.assertEqual(category.parent.rel_model, category)

        fkpk = models['fkpk']
        self.assertEqual(sorted(fkpk._meta.fields), ['col_types'])
        assertIsInstance(fkpk.col_types, ForeignKeyField)
        self.assertEqual(fkpk.col_types.rel_model, models['col_types'])
        self.assertTrue(fkpk.col_types.primary_key)

        relmodel = models['rel_model']
        self.assertEqual(
            sorted(relmodel._meta.fields),
            ['col_types', 'col_types_nullable', 'id'])
        assertIsInstance(relmodel.col_types, ForeignKeyField)
        assertIsInstance(relmodel.col_types_nullable, ForeignKeyField)
        self.assertFalse(relmodel.col_types.null)
        self.assertTrue(relmodel.col_types_nullable.null)
        self.assertEqual(relmodel.col_types.rel_model,
                         models['col_types'])
        self.assertEqual(relmodel.col_types_nullable.rel_model,
                         models['col_types'])

    @requires_sqlite
    def test_generate_models_indexes(self):
        models = self.introspector.generate_models()

        self.assertEqual(models['fkpk']._meta.indexes, [])
        self.assertEqual(models['rel_model']._meta.indexes, [])
        self.assertEqual(models['category']._meta.indexes, [])

        col_types = models['col_types']
        indexed = set(['f1'])
        unique = set(['f10'])
        for field in col_types._meta.sorted_fields:
            self.assertEqual(field.index, field.name in indexed)
            self.assertEqual(field.unique, field.name in unique)
        indexes = col_types._meta.indexes
        self.assertEqual(sorted(indexes), [
            (['f10', 'f11'], True),
            (['f11', 'f8', 'f13'], False),
        ])

    def test_table_subset(self):
        models = self.introspector.generate_models(table_names=[
            'category',
            'col_types',
            'foobarbaz'])
        self.assertEqual(sorted(models.keys()), ['category', 'col_types'])

    @requires_sqlite
    def test_sqlite_fk_re(self):
        user_id_tests = [
            'FOREIGN KEY("user_id") REFERENCES "users"("id")',
            'FOREIGN KEY(user_id) REFERENCES users(id)',
            'FOREIGN KEY  ([user_id])  REFERENCES  [users]  ([id])',
            '"user_id" NOT NULL REFERENCES "users" ("id")',
            'user_id not null references users (id)',
        ]
        fk_pk_tests = [
            ('"col_types_id" INTEGER NOT NULL PRIMARY KEY REFERENCES '
             '"coltypes" ("f11")'),
            'FOREIGN KEY ("col_types_id") REFERENCES "coltypes" ("f11")',
        ]
        regex = SqliteMetadata.re_foreign_key

        for test in user_id_tests:
            match = re.search(regex, test, re.I)
            self.assertEqual(match.groups(), (
                'user_id', 'users', 'id',
            ))

        for test in fk_pk_tests:
            match = re.search(regex, test, re.I)
            self.assertEqual(match.groups(), (
                'col_types_id', 'coltypes', 'f11',
            ))

    def test_make_column_name(self):
        # Tests for is_foreign_key=False.
        tests = (
            ('Column', 'column'),
            ('Foo_id', 'foo_id'),
            ('foo_id', 'foo_id'),
            ('foo_id_id', 'foo_id_id'),
            ('foo', 'foo'),
            ('_id', '_id'),
            ('a123', 'a123'),
            ('and', 'and_'),
            ('Class', 'class_'),
            ('Class_ID', 'class_id'),
            ('camelCase', 'camel_case'),
            ('ABCdefGhi', 'ab_cdef_ghi'),
        )
        for col_name, expected in tests:
            self.assertEqual(
                self.introspector.make_column_name(col_name), expected)

        # Tests for is_foreign_key=True.
        tests = (
            ('Foo_id', 'foo'),
            ('foo_id', 'foo'),
            ('foo_id_id', 'foo_id'),
            ('foo', 'foo'),
            ('_id', '_id'),
            ('a123', 'a123'),
            ('and', 'and_'),
            ('Class', 'class_'),
            ('Class_ID', 'class_'),
            ('camelCase', 'camel_case'),
            ('ABCdefGhi', 'ab_cdef_ghi'),
        )
        for col_name, expected in tests:
            self.assertEqual(
                self.introspector.make_column_name(col_name, True), expected)

    def test_make_model_name(self):
        tests = (
            ('Table', 'Table'),
            ('table', 'Table'),
            ('table_baz', 'TableBaz'),
            ('foo__bar__baz2', 'FooBarBaz2'),
            ('foo12_3', 'Foo123'),
        )
        for table_name, expected in tests:
            self.assertEqual(
                self.introspector.make_model_name(table_name), expected)

    def test_col_types(self):
        (columns,
         primary_keys,
         foreign_keys,
         model_names,
         indexes) = self.introspector.introspect()

        expected = (
            ('col_types', (
                ('f1', (BigIntegerField, IntegerField), False),
                # There do not appear to be separate constants for the blob and
                # text field types in MySQL's drivers. See GH#1034.
                ('f2', (BlobField, TextField), False),
                ('f3', (BooleanField, IntegerField), False),
                ('f4', CharField, False),
                ('f5', DateField, False),
                ('f6', DateTimeField, False),
                ('f7', DecimalField, False),
                ('f8', (DoubleField, FloatField), False),
                ('f9', FloatField, False),
                ('f10', IntegerField, False),
                ('f11', AutoField, False),
                ('f12', TextField, False),
                ('f13', TimeField, False))),
            ('rel_model', (
                ('col_types_id', ForeignKeyField, False),
                ('col_types_nullable_id', ForeignKeyField, True))),
            ('nugget', (
                ('category_id', ForeignKeyField, False),
                ('category', CharField, False))),
            ('nullable', (
                ('nullable_cf', CharField, True),
                ('nullable_if', IntegerField, True))),
            ('fkpk', (
                ('col_types_id', ForeignKeyField, False),)),
            ('underscores', (
                ('_id', AutoField, False),
                ('_name', CharField, False))),
            ('category', (
                ('name', CharField, False),
                ('parent_id', ForeignKeyField, True))),
        )

        for table_name, expected_columns in expected:
            introspected_columns = columns[table_name]

            for field_name, field_class, is_null in expected_columns:
                if not isinstance(field_class, (list, tuple)):
                    field_class = (field_class,)
                column = introspected_columns[field_name]
                self.assertTrue(column.field_class in field_class,
                                "%s in %s" % (column.field_class, field_class))
                self.assertEqual(column.nullable, is_null)

    def test_foreign_keys(self):
        (columns,
         primary_keys,
         foreign_keys,
         model_names,
         indexes) = self.introspector.introspect()

        self.assertEqual(foreign_keys['col_types'], [])

        rel_model = foreign_keys['rel_model']
        self.assertEqual(len(rel_model), 2)

        fkpk = foreign_keys['fkpk']
        self.assertEqual(len(fkpk), 1)

        fkpk_fk = fkpk[0]
        self.assertEqual(fkpk_fk.table, 'fkpk')
        self.assertEqual(fkpk_fk.column, 'col_types_id')
        self.assertEqual(fkpk_fk.dest_table, 'col_types')
        self.assertEqual(fkpk_fk.dest_column, 'f11')

        category = foreign_keys['category']
        self.assertEqual(len(category), 1)

        category_fk = category[0]
        self.assertEqual(category_fk.table, 'category')
        self.assertEqual(category_fk.column, 'parent_id')
        self.assertEqual(category_fk.dest_table, 'category')
        self.assertEqual(category_fk.dest_column, 'id')

    def test_table_names(self):
        (columns,
         primary_keys,
         foreign_keys,
         model_names,
         indexes) = self.introspector.introspect()

        names = (
            ('col_types', 'ColTypes'),
            ('nullable', 'Nullable'),
            ('rel_model', 'RelModel'),
            ('fkpk', 'Fkpk'))
        for k, v in names:
            self.assertEqual(model_names[k], v)

    def test_column_meta(self):
        (columns,
         primary_keys,
         foreign_keys,
         model_names,
         indexes) = self.introspector.introspect()

        rel_model = columns['rel_model']

        col_types_id = rel_model['col_types_id']
        self.assertEqual(col_types_id.get_field_parameters(), {
            'column_name': "'col_types_id'",
            'model': 'ColTypes',
            'field': "'f11'",
        })

        col_types_nullable_id = rel_model['col_types_nullable_id']
        self.assertEqual(col_types_nullable_id.get_field_parameters(), {
            'column_name': "'col_types_nullable_id'",
            'null': True,
            'backref': "'col_types_col_types_nullable_set'",
            'model': 'ColTypes',
            'field': "'f11'",
        })

        fkpk = columns['fkpk']
        self.assertEqual(fkpk['col_types_id'].get_field_parameters(), {
            'column_name': "'col_types_id'",
            'model': 'ColTypes',
            'primary_key': True,
            'field': "'f11'"})

        category = columns['category']

        parent_id = category['parent_id']
        self.assertEqual(parent_id.get_field_parameters(), {
            'column_name': "'parent_id'",
            'null': True,
            'model': "'self'",
            'field': "'id'",
        })

        nugget = columns['nugget']
        category_fk = nugget['category_id']
        self.assertEqual(category_fk.name, 'category_id')
        self.assertEqual(category_fk.get_field_parameters(), {
            'field': "'id'",
            'model': 'Category',
            'column_name': "'category_id'",
        })

        category = nugget['category']
        self.assertEqual(category.name, 'category')

    def test_fk_on_delete_update(self):
        self.database.execute_sql(
            'CREATE TABLE odu ('
            'id INTEGER PRIMARY KEY, '
            'rel_model_id INTEGER, '
            'FOREIGN KEY (rel_model_id) REFERENCES rel_model (id) '
            'ON DELETE CASCADE ON UPDATE SET NULL)')
        try:
            (columns, primary_keys, foreign_keys, model_names,
             indexes) = self.introspector.introspect()
            params = columns['odu']['rel_model_id'].get_field_parameters()
            self.assertEqual(params.get('on_delete'), "'CASCADE'")
            self.assertEqual(params.get('on_update'), "'SET NULL'")
            self.assertNotIn('attr', params)
        finally:
            self.database.execute_sql('DROP TABLE odu')

    def test_get_field(self):
        (columns,
         primary_keys,
         foreign_keys,
         model_names,
         indexes) = self.introspector.introspect()

        expected = (
            ('col_types', (
                ('f1', ('f1 = BigIntegerField(index=True)',
                        'f1 = IntegerField(index=True)')),
                ('f2', ('f2 = BlobField()', 'f2 = TextField()')),
                ('f4', 'f4 = CharField(max_length=50)'),
                ('f5', 'f5 = DateField()'),
                ('f6', 'f6 = DateTimeField()'),
                ('f7', 'f7 = DecimalField()'),
                ('f10', 'f10 = IntegerField(unique=True)'),
                ('f11', 'f11 = AutoField()'),
                ('f12', ('f12 = TextField()', 'f12 = BlobField()')),
                ('f13', 'f13 = TimeField()'),
            )),
            ('nullable', (
                ('nullable_cf', 'nullable_cf = '
                 'CharField(null=True)'),
                ('nullable_if', 'nullable_if = IntegerField(null=True)'),
            )),
            ('fkpk', (
                ('col_types_id', 'col_types = ForeignKeyField('
                 "column_name='col_types_id', field='f11', model=ColTypes, "
                 'primary_key=True)'),
            )),
            ('nugget', (
                ('category_id', 'category_id = ForeignKeyField('
                 "column_name='category_id', field='id', model=Category)"),
                ('category', 'category = CharField()'),
            )),
            ('rel_model', (
                ('col_types_id', 'col_types = ForeignKeyField('
                 "column_name='col_types_id', field='f11', model=ColTypes)"),
                ('col_types_nullable_id', 'col_types_nullable = '
                 "ForeignKeyField(backref='col_types_col_types_nullable_set', "
                 "column_name='col_types_nullable_id', field='f11', "
                 'model=ColTypes, null=True)'),
            )),
            ('underscores', (
                ('_id', '_id = AutoField()'),
                ('_name', '_name = CharField()'),
            )),
            ('category', (
                ('name', 'name = CharField(max_length=10)'),
                ('parent_id', 'parent = ForeignKeyField('
                 "column_name='parent_id', field='id', model='self', "
                 'null=True)'),
            )),
        )

        for table, field_data in expected:
            for field_name, fields in field_data:
                if not isinstance(fields, tuple):
                    fields = (fields,)
                actual = columns[table][field_name].get_field()
                self.assertTrue(actual in fields,
                                '%s not in %s' % (actual, fields))


class TestReflectNoPK(BaseReflectionTestCase):
    requires = [NoPK]

    def test_no_pk(self):
        models = self.introspector.generate_models()
        NoPK = models['no_pk']
        if IS_CRDB:
            # CockroachDB always includes a "rowid".
            self.assertEqual(NoPK._meta.sorted_field_names, ['rowid', 'data'])
        else:
            self.assertEqual(NoPK._meta.sorted_field_names, ['data'])
            self.assertTrue(NoPK._meta.primary_key is False)


class EventLog(TestModel):
    data = CharField(constraints=[SQL('DEFAULT \'\'')])
    timestamp = DateTimeField(constraints=[SQL('DEFAULT current_timestamp')])
    flags = IntegerField(constraints=[SQL('DEFAULT 0')])
    misc = TextField(constraints=[SQL('DEFAULT \'foo\'')])


class DefaultVals(TestModel):
    key = CharField(constraints=[SQL('DEFAULT \'foo\'')])
    value = IntegerField(constraints=[SQL('DEFAULT 0')])

    class Meta:
        primary_key = CompositeKey('key', 'value')


class TestReflectDefaultValues(BaseReflectionTestCase):
    requires = [DefaultVals, EventLog]

    @requires_sqlite
    def test_default_values(self):
        models = self.introspector.generate_models()
        default_vals = models['default_vals']

        create_table = (
            'CREATE TABLE IF NOT EXISTS "default_vals" ('
            '"key" VARCHAR(255) NOT NULL DEFAULT \'foo\', '
            '"value" INTEGER NOT NULL DEFAULT 0, '
            'PRIMARY KEY ("key", "value"))')

        # Re-create table using the introspected schema.
        self.assertSQL(default_vals._schema._create_table(), create_table, [])
        default_vals.drop_table()
        default_vals.create_table()

        # Verify that the introspected schema has not changed.
        models = self.introspector.generate_models()
        default_vals = models['default_vals']
        self.assertSQL(default_vals._schema._create_table(), create_table, [])

    @requires_sqlite
    def test_default_values_extended(self):
        models = self.introspector.generate_models()
        eventlog = models['event_log']

        create_table = (
            'CREATE TABLE IF NOT EXISTS "event_log" ('
            '"id" INTEGER NOT NULL PRIMARY KEY, '
            '"data" VARCHAR(255) NOT NULL DEFAULT \'\', '
            '"timestamp" DATETIME NOT NULL DEFAULT current_timestamp, '
            '"flags" INTEGER NOT NULL DEFAULT 0, '
            '"misc" TEXT NOT NULL DEFAULT \'foo\')')

        # Re-create table using the introspected schema.
        self.assertSQL(eventlog._schema._create_table(), create_table, [])
        eventlog.drop_table()
        eventlog.create_table()

        # Verify that the introspected schema has not changed.
        models = self.introspector.generate_models()
        eventlog = models['event_log']
        self.assertSQL(eventlog._schema._create_table(), create_table, [])


class TestReflectionDependencies(BaseReflectionTestCase):
    requires = [User, Tweet]

    def test_generate_dependencies(self):
        models = self.introspector.generate_models(table_names=['tweet'])
        self.assertEqual(set(models), set(('users', 'tweet')))

        IUser = models['users']
        ITweet = models['tweet']

        self.assertEqual(set(ITweet._meta.fields), set((
            'id', 'user', 'content', 'timestamp')))
        self.assertEqual(set(IUser._meta.fields), set(('id', 'username')))
        self.assertTrue(ITweet.user.rel_model is IUser)
        self.assertTrue(ITweet.user.rel_field is IUser.id)

    def test_ignore_backrefs(self):
        models = self.introspector.generate_models(table_names=['users'])
        self.assertEqual(set(models), set(('users',)))


class Note(TestModel):
    content = TextField()
    timestamp = DateTimeField(default=datetime.datetime.now)
    status = IntegerField()


class TestReflectViews(BaseReflectionTestCase):
    requires = [Note]

    def setUp(self):
        super(TestReflectViews, self).setUp()
        self.database.execute_sql('CREATE VIEW notes_public AS '
                                  'SELECT content, timestamp FROM note '
                                  'WHERE status = 1 ORDER BY timestamp DESC')

    def tearDown(self):
        self.database.execute_sql('DROP VIEW notes_public')
        super(TestReflectViews, self).tearDown()

    def test_views_ignored_default(self):
        models = self.introspector.generate_models()
        self.assertFalse('notes_public' in models)

    def test_introspect_view(self):
        models = self.introspector.generate_models(include_views=True)
        self.assertTrue('notes_public' in models)

        NotesPublic = models['notes_public']
        self.assertEqual(sorted(NotesPublic._meta.fields),
                         ['content', 'timestamp'])
        self.assertTrue(isinstance(NotesPublic.content, TextField))
        self.assertTrue(isinstance(NotesPublic.timestamp, DateTimeField))

    @skip_if(IS_SQLITE_OLD)
    @skip_if(IS_CRDB, 'crdb does not respect order by in view def')
    def test_introspect_view_integration(self):
        for i, (ct, st) in enumerate([('n1', 1), ('n2', 2), ('n3', 1)]):
            Note.create(content=ct, status=st,
                        timestamp=datetime.datetime(2018, 1, 1 + i))

        NP = self.introspector.generate_models(
            table_names=['notes_public'], include_views=True)['notes_public']
        self.assertEqual([(np.content, np.timestamp) for np in NP.select()], [
            ('n3', datetime.datetime(2018, 1, 3)),
            ('n1', datetime.datetime(2018, 1, 1))])


class TestCyclicalFK(BaseReflectionTestCase):
    def setUp(self):
        super(TestCyclicalFK, self).setUp()
        warnings.filterwarnings('ignore')

    @requires_sqlite
    @skip_if(IS_CYSQLITE, 'cysqlite does not implement cursor at the moment.')
    def test_cyclical_fk(self):
        # NOTE: this schema was provided by a user.
        cursor = self.database.cursor()
        cursor.executescript(
            'CREATE TABLE flow_run_state (id CHAR(36) NOT NULL, '
            'flow_run_id CHAR(36) NOT NULL, '
	    'CONSTRAINT pk_flow_run_state PRIMARY KEY (id), '
	    'CONSTRAINT fk_flow_run_state__flow_run_id__flow_run '
            'FOREIGN KEY(flow_run_id) REFERENCES flow_run (id) '
            'ON DELETE cascade); '
            'CREATE TABLE flow_run (id CHAR(36) NOT NULL, '
	    'state_id CHAR(36) NOT NULL, '
	    'CONSTRAINT pk_flow_run PRIMARY KEY (id), '
	    'CONSTRAINT fk_flow_run__state_id__flow_run_state '
            'FOREIGN KEY(state_id) REFERENCES flow_run_state (id) '
            'ON DELETE SET NULL);')
        M = self.introspector.generate_models()
        FRS = M['flow_run_state']
        FR = M['flow_run']
        self.assertEqual(sorted(FR._meta.fields), ['id', 'state'])
        self.assertEqual(sorted(FRS._meta.fields), ['flow_run', 'id'])
        self.assertTrue(isinstance(FR.id, CharField))
        self.assertTrue(isinstance(FR.state, ForeignKeyField))
        self.assertTrue(FR.state.rel_model is FRS)
        self.assertTrue(isinstance(FRS.id, CharField))
        self.assertTrue(isinstance(FRS.flow_run, ForeignKeyField))
        self.assertTrue(FRS.flow_run.rel_model is FR)


class Event(TestModel):
    key = TextField()
    timestamp = DateTimeField(index=True)
    metadata = TextField(default='')


class TestInteractiveHelpers(ModelTestCase):
    requires = [Category, Event]

    def test_generate_models(self):
        M = generate_models(self.database)
        self.assertTrue('category' in M)
        self.assertTrue('event' in M)

        def assertFields(m, expected):
            actual = [(f.name, f.field_type) for f in m._meta.sorted_fields]
            self.assertEqual(actual, expected)

        assertFields(M['category'], [('id', 'AUTO'), ('name', 'VARCHAR'),
                                     ('parent', 'INT')])
        assertFields(M['event'], [
            ('id', 'AUTO'),
            ('key', 'TEXT'),
            ('timestamp', 'DATETIME'),
            ('metadata', 'TEXT')])


class Facets(TestModel):
    char50 = CharField(max_length=50)
    dec = DecimalField(max_digits=10, decimal_places=2)
    truthy = BooleanField()
    blob = BlobField()
    dbl = DoubleField()
    small = SmallIntegerField()
    timestamp = DateTimeField(index=True)


class FacetParent(TestModel):
    name = CharField(default='')

class FacetChild(TestModel):
    parent = ForeignKeyField(FacetParent, backref='kids',
                             on_delete='CASCADE', on_update='CASCADE')


@skip_if(IS_CRDB)
class TestReflectionFacets(BaseReflectionTestCase):
    requires = [Facets, FacetParent, FacetChild]

    def test_field_type_parameters(self):
        models = self.introspector.generate_models()
        F = models[Facets._meta.table_name]
        self.assertEqual(F.char50.max_length, 50)
        self.assertEqual(F.dec.max_digits, 10)
        self.assertEqual(F.dec.decimal_places, 2)

    def test_field_classes(self):
        models = self.introspector.generate_models()
        F = models[Facets._meta.table_name]
        if IS_SQLITE:
            # Truthy/small are stored with INTEGER affinity, dbl as REAL.
            expected = (IntegerField, BlobField, FloatField, IntegerField)
        else:
            expected = (BooleanField, BlobField, DoubleField,
                        SmallIntegerField)
        for name, field_class in zip(('truthy', 'blob', 'dbl', 'small'),
                                     expected):
            self.assertTrue(type(getattr(F, name)) is field_class,
                            '%s: %s' % (name, type(getattr(F, name))))

    def test_reserved_word_index(self):
        models = self.introspector.generate_models()
        F = models[Facets._meta.table_name]
        self.assertTrue(F.timestamp.index)
        self.assertTrue(type(F.timestamp) is DateTimeField)

    def test_fk_actions(self):
        models = self.introspector.generate_models()
        C = models[FacetChild._meta.table_name]
        fk = C._meta.columns['parent_id']
        self.assertEqual(fk.on_delete, 'CASCADE')
        self.assertEqual(fk.on_update, 'CASCADE')

    def test_int_pk_not_promoted(self):
        self.database.execute_sql('DROP TABLE IF EXISTS facet_intpk')
        self.database.execute_sql(
            'CREATE TABLE facet_intpk ('
            'id INTEGER NOT NULL PRIMARY KEY, data TEXT)')
        try:
            models = self.introspector.generate_models(
                table_names=['facet_intpk'])
            pk = models['facet_intpk']._meta.primary_key
            if IS_SQLITE:
                # An INTEGER pk is a rowid alias, i.e. auto-incrementing.
                self.assertTrue(isinstance(pk, AutoField))
            else:
                self.assertFalse(isinstance(pk, AutoField))
                self.assertTrue(pk.primary_key)
        finally:
            self.database.execute_sql('DROP TABLE facet_intpk')

    @skip_if(IS_MYSQL, 'mysql does not support partial indexes')
    def test_partial_index_skipped(self):
        table = Facets._meta.table_name
        self.database.execute_sql(
            'CREATE INDEX facets_partial ON %s (char50) WHERE dec > 0'
            % table)
        try:
            metadata = self.introspector.introspect(table_names=[table])
            column = metadata.columns[table]['char50']
            self.assertFalse(column.index)
            unhandled = metadata.unhandled_indexes(table)
            self.assertEqual([idx.name for idx in unhandled],
                             ['facets_partial'])
        finally:
            self.database.execute_sql('DROP INDEX facets_partial')

    @skip_if(IS_MYSQL, 'mysql functional indexes are not reflected')
    def test_expression_index_skipped(self):
        table = Facets._meta.table_name
        self.database.execute_sql(
            'CREATE INDEX facets_expr ON %s (LOWER(char50))' % table)
        try:
            metadata = self.introspector.introspect(table_names=[table])
            self.assertFalse(metadata.columns[table]['char50'].index)
            unhandled = metadata.unhandled_indexes(table)
            self.assertEqual([idx.name for idx in unhandled],
                             ['facets_expr'])
        finally:
            self.database.execute_sql('DROP INDEX facets_expr')
