# Copyright (c) 2012 NTT DOCOMO, INC.
# 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.

"""Magnum DB test base class."""

import os
import shutil

import fixtures
from oslo.config import cfg

from magnum.common import paths
from magnum.db import api as dbapi
from magnum.db.sqlalchemy import api as sqla_api
from magnum.db.sqlalchemy import migration
from magnum.db.sqlalchemy import models
from magnum.tests import base


CONF = cfg.CONF

CONF.import_opt('enable_authentication', 'magnum.api.auth')

_DB_CACHE = None


class Database(fixtures.Fixture):

    def __init__(self, db_api, db_migrate, sql_connection,
                    sqlite_db, sqlite_clean_db):
        self.sql_connection = sql_connection
        self.sqlite_db = sqlite_db
        self.sqlite_clean_db = sqlite_clean_db

        self.engine = db_api.get_engine()
        self.engine.dispose()
        conn = self.engine.connect()
        if sql_connection == "sqlite://":
            self.setup_sqlite(db_migrate)
        elif sql_connection.startswith('sqlite:///'):
            testdb = paths.state_path_rel(sqlite_db)
            if os.path.exists(testdb):
                return
            self.setup_sqlite(db_migrate)
        else:
            db_migrate.upgrade('head')
        self.post_migrations()
        if sql_connection == "sqlite://":
            conn = self.engine.connect()
            self._DB = "".join(line for line in conn.connection.iterdump())
            self.engine.dispose()
        else:
            cleandb = paths.state_path_rel(sqlite_clean_db)
            shutil.copyfile(testdb, cleandb)

    def setup_sqlite(self, db_migrate):
        if db_migrate.version():
            return
        models.Base.metadata.create_all(self.engine)
        db_migrate.stamp('head')

    def setUp(self):
        super(Database, self).setUp()

        if self.sql_connection == "sqlite://":
            conn = self.engine.connect()
            conn.connection.executescript(self._DB)
            self.addCleanup(self.engine.dispose)
        else:
            shutil.copyfile(paths.state_path_rel(self.sqlite_clean_db),
                            paths.state_path_rel(self.sqlite_db))
            self.addCleanup(os.unlink, self.sqlite_db)

    def post_migrations(self):
        """Any addition steps that are needed outside of the migrations."""


class DbTestCase(base.TestCase):

    def setUp(self):
        cfg.CONF.set_override("enable_authentication", False)
        super(DbTestCase, self).setUp()

        self.dbapi = dbapi.get_instance()

        global _DB_CACHE
        if not _DB_CACHE:
            _DB_CACHE = Database(sqla_api, migration,
                                 sql_connection=CONF.database.connection,
                                 sqlite_db=CONF.database.sqlite_db,
                                 sqlite_clean_db='clean.sqlite')
        self.useFixture(_DB_CACHE)