#  Copyright 2021 Collate
#  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 ibm_db_sa.base import DB2Dialect
from sqlalchemy.engine import reflection
from sqlalchemy.engine.reflection import Inspector

from metadata.generated.schema.entity.services.connections.metadata.openMetadataConnection import (
    OpenMetadataConnection,
)
from metadata.generated.schema.metadataIngestion.workflow import (
    Source as WorkflowSource,
)
from metadata.ingestion.api.source import InvalidSourceException
from metadata.ingestion.source.database.common_db_source import CommonDbSourceService


@reflection.cache
def get_pk_constraint(self, bind, table_name, schema=None, **kw):
    return {"constrained_columns": [], "name": "undefined"}


DB2Dialect.get_pk_constraint = get_pk_constraint
from metadata.generated.schema.entity.services.connections.database.db2Connection import (
    Db2Connection,
)


class Db2Source(CommonDbSourceService):
    def __init__(self, config, metadata_config):
        super().__init__(config, metadata_config)

    @classmethod
    def create(cls, config_dict, metadata_config: OpenMetadataConnection):
        config: WorkflowSource = WorkflowSource.parse_obj(config_dict)
        connection: Db2Connection = config.serviceConnection.__root__.config
        if not isinstance(connection, Db2Connection):
            raise InvalidSourceException(
                f"Expected Db2Connection, but got {connection}"
            )
        return cls(config, metadata_config)
