# Copyright 2016 Huawei Technologies Co.,LTD.
# 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.

"""
SQLAlchemy models for baremetal compute service.
"""

from oslo_db import options as db_options
from oslo_db.sqlalchemy import models
from oslo_db.sqlalchemy import types as db_types
import six.moves.urllib.parse as urlparse
from sqlalchemy import Boolean, Column, DateTime, ForeignKey
from sqlalchemy import orm
from sqlalchemy import schema, String, Integer
from sqlalchemy.ext.declarative import declarative_base

from mogan.common import paths
from mogan.conf import CONF

_DEFAULT_SQL_CONNECTION = 'sqlite:///' + paths.state_path_def('mogan.sqlite')


db_options.set_defaults(CONF, _DEFAULT_SQL_CONNECTION, 'mogan.sqlite')


def table_args():
    engine_name = urlparse.urlparse(CONF.database.connection).scheme
    if engine_name == 'mysql':
        return {'mysql_engine': CONF.database.mysql_engine,
                'mysql_charset': "utf8"}
    return None


class MoganBase(models.TimestampMixin,
                models.ModelBase):

    metadata = None

    def as_dict(self):
        d = {}
        for c in self.__table__.columns:
            d[c.name] = self[c.name]
        return d


Base = declarative_base(cls=MoganBase)


class Instance(Base):
    """Represents possible types for instances."""

    __tablename__ = 'instances'
    __table_args__ = (
        schema.UniqueConstraint('uuid', name='uniq_instances0uuid'),
        table_args()
    )
    id = Column(Integer, primary_key=True)
    uuid = Column(String(36), nullable=False)
    name = Column(String(255), nullable=False)
    description = Column(String(255), nullable=True)
    project_id = Column(String(36), nullable=True)
    user_id = Column(String(36), nullable=True)
    status = Column(String(255), nullable=True)
    power_state = Column(String(15), nullable=True)
    instance_type_uuid = Column(String(36), nullable=True)
    availability_zone = Column(String(255), nullable=True)
    image_uuid = Column(String(36), nullable=True)
    network_info = Column(db_types.JsonEncodedDict)
    node_uuid = Column(String(36), nullable=True)
    launched_at = Column(DateTime, nullable=True)
    deleted_at = Column(DateTime, nullable=True)
    extra = Column(db_types.JsonEncodedDict)
    deleted = Column(Boolean, default=False)


class InstanceTypes(Base):
    """Represents possible types for instances."""

    __tablename__ = 'instance_types'
    uuid = Column(String(36), primary_key=True)
    name = Column(String(255), nullable=False)
    description = Column(String(255), nullable=True)
    is_public = Column(Boolean, default=True)
    instances = orm.relationship(
        Instance,
        backref=orm.backref('instance_type', uselist=False),
        foreign_keys=uuid,
        primaryjoin='Instance.instance_type_uuid == InstanceTypes.uuid')


class InstanceTypeProjects(Base):
    """Represents projects associated instance_types."""

    __tablename__ = 'instance_type_projects'
    __table_args__ = (
        schema.UniqueConstraint(
            'instance_type_uuid', 'project_id',
            name='uniq_instance_type_projects0instance_type_uuid0project_id'
        ),
        table_args()
    )
    id = Column(Integer, primary_key=True)
    instance_type_uuid = Column(Integer, nullable=True)
    project_id = Column(String(36), nullable=True)
    instances = orm.relationship(
        InstanceTypes,
        backref=orm.backref('projects', uselist=False),
        foreign_keys=instance_type_uuid,
        primaryjoin='InstanceTypeProjects.instance_type_uuid'
                    ' == InstanceTypes.uuid')


class InstanceTypeExtraSpecs(Base):
    """Represents additional specs as key/value pairs for an instance_type."""
    __tablename__ = 'instance_type_extra_specs'
    __table_args__ = (
        schema.UniqueConstraint(
            "instance_type_uuid", "key",
            name=("uniq_instance_type_extra_specs0"
                  "instance_type_uuid")
        ),
        {'mysql_collate': 'utf8_bin'},
    )
    id = Column(Integer, primary_key=True)
    key = Column(String(255))
    value = Column(String(255))
    instance_type_uuid = Column(String(36), ForeignKey('instance_types.uuid'),
                                nullable=False)
    instance_type = orm.relationship(
        InstanceTypes, backref="extra_specs",
        foreign_keys=instance_type_uuid,
        primaryjoin='InstanceTypeExtraSpecs.instance_type_uuid '
                    '== InstanceTypes.uuid')