# -*- coding: utf-8 -*-
#
# 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 airflow.contrib.hooks.redshift_hook import RedshiftHook
from airflow.sensors.base_sensor_operator import BaseSensorOperator
from airflow.utils.decorators import apply_defaults


class AwsRedshiftClusterSensor(BaseSensorOperator):
    """
    Waits for a Redshift cluster to reach a specific status.

    :param cluster_identifier: The identifier for the cluster being pinged.
    :type cluster_identifier: str
    :param target_status: The cluster status desired.
    :type target_status: str
    """
    template_fields = ('cluster_identifier', 'target_status')

    @apply_defaults
    def __init__(self,
                 cluster_identifier,
                 target_status='available',
                 aws_conn_id='aws_default',
                 *args,
                 **kwargs):
        super(AwsRedshiftClusterSensor, self).__init__(*args, **kwargs)
        self.cluster_identifier = cluster_identifier
        self.target_status = target_status
        self.aws_conn_id = aws_conn_id

    def poke(self, context):
        self.log.info('Poking for status : {self.target_status}\n'
                      'for cluster {self.cluster_identifier}'.format(**locals()))
        hook = RedshiftHook(aws_conn_id=self.aws_conn_id)
        return hook.cluster_status(self.cluster_identifier) == self.target_status
