# Copyright 2013 Mirantis Inc.
# All Rights Reserved
#
#    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 six

from neutronclient._i18n import _
from neutronclient.neutron import v2_0 as neutronV20


def _format_provider(pool):
    return pool.get('provider') or 'N/A'


class ListPool(neutronV20.ListCommand):
    """List pools that belong to a given tenant."""

    resource = 'pool'
    list_columns = ['id', 'name', 'provider', 'lb_method', 'protocol',
                    'admin_state_up', 'status']
    _formatters = {'provider': _format_provider}
    pagination_support = True
    sorting_support = True


class ShowPool(neutronV20.ShowCommand):
    """Show information of a given pool."""

    resource = 'pool'


class CreatePool(neutronV20.CreateCommand):
    """Create a pool."""

    resource = 'pool'

    def add_known_arguments(self, parser):
        parser.add_argument(
            '--admin-state-down',
            dest='admin_state', action='store_false',
            help=_('Set admin state up to false.'))
        parser.add_argument(
            '--description',
            help=_('Description of the pool.'))
        parser.add_argument(
            '--lb-method',
            required=True,
            choices=['ROUND_ROBIN', 'LEAST_CONNECTIONS', 'SOURCE_IP'],
            help=_('The algorithm used to distribute load between the members '
                   'of the pool.'))
        parser.add_argument(
            '--name',
            required=True,
            help=_('The name of the pool.'))
        parser.add_argument(
            '--protocol',
            required=True,
            choices=['HTTP', 'HTTPS', 'TCP'],
            help=_('Protocol for balancing.'))
        parser.add_argument(
            '--subnet-id', metavar='SUBNET',
            required=True,
            help=_('The subnet on which the members of the pool will be '
                   'located.'))
        parser.add_argument(
            '--provider',
            help=_('Provider name of the loadbalancer service.'))

    def args2body(self, parsed_args):
        _subnet_id = neutronV20.find_resourceid_by_name_or_id(
            self.get_client(), 'subnet', parsed_args.subnet_id)
        body = {'admin_state_up': parsed_args.admin_state,
                'subnet_id': _subnet_id}
        neutronV20.update_dict(parsed_args, body,
                               ['description', 'lb_method', 'name',
                                'protocol', 'tenant_id', 'provider'])
        return {self.resource: body}


class UpdatePool(neutronV20.UpdateCommand):
    """Update a given pool."""

    resource = 'pool'


class DeletePool(neutronV20.DeleteCommand):
    """Delete a given pool."""

    resource = 'pool'


class RetrievePoolStats(neutronV20.ShowCommand):
    """Retrieve stats for a given pool."""

    resource = 'pool'

    def take_action(self, parsed_args):
        neutron_client = self.get_client()
        pool_id = neutronV20.find_resourceid_by_name_or_id(
            self.get_client(), 'pool', parsed_args.id)
        params = {}
        if parsed_args.fields:
            params = {'fields': parsed_args.fields}

        data = neutron_client.retrieve_pool_stats(pool_id, **params)
        self.format_output_data(data)
        stats = data['stats']
        if 'stats' in data:
            return zip(*sorted(six.iteritems(stats)))
        else:
            return None
