# Copyright 2014 Rackspace
# All Rights Reserved.
#
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

from sqlalchemy import ForeignKey
from sqlalchemy.schema import Column
from sqlalchemy.schema import MetaData

from trove.db.sqlalchemy.migrate_repo.schema import Boolean
from trove.db.sqlalchemy.migrate_repo.schema import create_tables
from trove.db.sqlalchemy.migrate_repo.schema import DateTime
from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
from trove.db.sqlalchemy.migrate_repo.schema import String
from trove.db.sqlalchemy.migrate_repo.schema import Table
from trove.db.sqlalchemy import utils as db_utils


meta = MetaData()

configurations = Table(
    'configurations',
    meta,
    Column('id', String(36), primary_key=True, nullable=False),
    Column('name', String(64), nullable=False),
    Column('description', String(256)),
    Column('tenant_id', String(36), nullable=False),
    Column('datastore_version_id', String(36), nullable=False),
    Column('deleted', Boolean(), nullable=False, default=False),
    Column('deleted_at', DateTime()),
)

configuration_parameters = Table(
    'configuration_parameters',
    meta,
    Column('configuration_id', String(36), ForeignKey("configurations.id"),
           nullable=False, primary_key=True),
    Column('configuration_key', String(128), nullable=False, primary_key=True),
    Column('configuration_value', String(128)),
    Column('deleted', Boolean(), nullable=False, default=False),
    Column('deleted_at', DateTime()),
)


def upgrade(migrate_engine):
    meta.bind = migrate_engine
    create_tables([configurations])
    create_tables([configuration_parameters])
    instances = Table('instances', meta, autoload=True)
    instances.create_column(Column('configuration_id', String(36),
                                   ForeignKey("configurations.id")))


def downgrade(migrate_engine):
    meta.bind = migrate_engine
    instances = Table('instances', meta, autoload=True)
    constraint_names = db_utils.get_foreign_key_constraint_names(
        engine=migrate_engine,
        table='instances',
        columns=['configuration_id'],
        ref_table='configurations',
        ref_columns=['id'])
    db_utils.drop_foreign_key_constraints(
        constraint_names=constraint_names,
        columns=[instances.c.configuration_id],
        ref_columns=[configurations.c.id])
    instances.drop_column('configuration_id')
    drop_tables([configuration_parameters, configurations])
