#    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.

import time
from salt.exceptions import CommandExecutionError

from heatv1.common import send

@send('get')
def service_list(cloud_name):
    """Return list of Heat services."""
    url = '/services'
    return url, {}

def wait_for_service(cloud_name, host=None, binary=None, retries=18, timeout=10):
    """Ensure the service is up and running on specified host.

    :param host:           name of a host where service is running
    :param binary:         name of the service
    :param timeout:        number of seconds to wait before retries
    :param retries:        number of retries
    """
    for _i in range(retries):
        services = service_list(cloud_name=cloud_name)['body']['services']

        down_services = [s for s in services if s['status'] == 'down']

        # When Heat worker is reloaded, it creates new instance with different Engine ID.
        # This is needed for checking that at least one instance on the host is running.
        up_services_hosts = {s['host'] for s in services if s['status'] == 'up'}

        if host:
            down_services = [s for s in down_services if s['host'] == host \
                                                      and s['host'] not in up_services_hosts]

        if binary:
            down_services = [s for s in down_services if s['binary'] == binary \
                                                      and s['host'] not in up_services_hosts]

        if not host and not binary:
            down_services = [s for s in down_services if s['host'] not in up_services_hosts]

        if not down_services:
            return 'Heat services are running.'
        time.sleep(timeout)

    raise CommandExecutionError("Heat services {} are still down".format(down_services))