# ============LICENSE_START===================================================
#  Copyright (C) 2020 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=====================================================

from mod import pmsh_logging as logger, db
from mod.db_models import NetworkFunctionModel


class NetworkFunction:
    def __init__(self, **kwargs):
        """
        Object representation of the NetworkFunction.
        """
        self.nf_name = kwargs.get('nf_name')
        self.orchestration_status = kwargs.get('orchestration_status')

    @classmethod
    def nf_def(cls):
        return cls(nf_name=None, orchestration_status=None)

    def __str__(self):
        return f'nf-name: {self.nf_name}, orchestration-status: {self.orchestration_status}'

    def create(self):
        """ Creates a NetworkFunction database entry
        """
        existing_nf = NetworkFunctionModel.query.filter(
            NetworkFunctionModel.nf_name == self.nf_name).one_or_none()

        if existing_nf is None:
            new_nf = NetworkFunctionModel(nf_name=self.nf_name,
                                          orchestration_status=self.orchestration_status)
            db.session.add(new_nf)
            db.session.commit()

            return new_nf
        else:
            logger.debug(f'Network function {existing_nf} already exists,'
                         f' returning this network function..')
            return existing_nf

    @staticmethod
    def get(nf_name):
        """ Retrieves a network function
        Args:
            nf_name (str): The network function name
        Returns:
            NetworkFunctionModel object else None
        """
        return NetworkFunctionModel.query.filter(
            NetworkFunctionModel.nf_name == nf_name).one_or_none()

    @staticmethod
    def get_all():
        """ Retrieves all network functions
        Returns:
            list: NetworkFunctionModel objects else empty
        """
        return NetworkFunctionModel.query.all()