# ============LICENSE_START===================================================
#  Copyright (C) 2019-2021 Nordix Foundation.
# ============================================================================
# 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.
#
# SPDX-License-Identifier: Apache-2.0
# ============LICENSE_END=====================================================
import sys
from signal import signal, SIGTERM

from mod import db, create_app, launch_api_server, logger
from mod.exit_handler import ExitHandler
from mod.pmsh_utils import AppConfig, PeriodicTask
from mod.policy_response_handler import PolicyResponseHandler
from mod.subscription_handler import SubscriptionHandler


def main():
    try:
        try:
            app = create_app()
            app.app_context().push()
            db.create_all(app=app)
            app_conf = AppConfig()
            policy_mr_pub = app_conf.get_mr_pub('policy_pm_publisher')
            policy_mr_sub = app_conf.get_mr_sub('policy_pm_subscriber')
            aai_event_mr_sub = app_conf.get_mr_sub('aai_subscriber')
        except Exception as e:
            logger.error(f'Failed to get config and create application: {e}', exc_info=True)
            sys.exit(e)

        policy_response_handler = PolicyResponseHandler(policy_mr_sub, app_conf, app)
        policy_response_handler_thread = PeriodicTask(25, policy_response_handler.poll_policy_topic)
        policy_response_handler_thread.name = 'policy_event_thread'
        logger.info('Start polling PMSH_CL_INPUT topic on DMaaP MR.')
        policy_response_handler_thread.start()

        subscription_handler = SubscriptionHandler(policy_mr_pub, aai_event_mr_sub, app, app_conf)
        subscription_handler_thread = PeriodicTask(20, subscription_handler.execute)
        subscription_handler_thread.name = 'sub_handler_thread'
        subscription_handler_thread.start()

        periodic_tasks = [subscription_handler_thread, policy_response_handler_thread]

        signal(SIGTERM, ExitHandler(periodic_tasks=periodic_tasks,
                                    app_conf=app_conf, subscription_handler=subscription_handler))
        launch_api_server(app_conf)

    except Exception as e:
        logger.error(f'Failed to initialise PMSH: {e}', exc_info=True)
        sys.exit(e)


if __name__ == '__main__':
    main()