# Copyright (c) 2011 OpenStack, LLC.
# 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.

from novaclient import base

from reddwarfclient.common import check_for_exceptions
from reddwarfclient.instances import Instance

class RootHistory(base.Resource):
    def __repr__(self):
      return ("<Root History: Instance %s enabled at %s by %s>"
            % (self.id, self.root_enabled_at, self.root_enabled_by))

class Management(base.ManagerWithFind):
    """
    Manage :class:`Instances` resources.
    """
    resource_class = Instance

    def _list(self, url, response_key):
        resp, body = self.api.client.get(url)
        if not body:
            raise Exception("Call to " + url + " did not return a body.")
        return self.resource_class(self, body[response_key])

    def show(self, instance):
        """
        Get details of one instance.

        :rtype: :class:`Instance`.
        """
        
        return self._list("/mgmt/instances/%s" % base.getid(instance),
            'instance')

    def index(self, deleted=None):
        """
        Show an overview of all local instances.
        Optionally, filter by deleted status.

        :rtype: list of :class:`Instance`.
        """
        form = ''
        if deleted is not None:
            if deleted:
                form = "?deleted=true"
            else:
                form = "?deleted=false"

        url = "/mgmt/instances%s" % form
        resp, body = self.api.client.get(url)
        if not body:
            raise Exception("Call to " + url + " did not return a body.")
        return [self.resource_class(self, instance) for instance in body['instances']]

    def root_enabled_history(self, instance):
        """
        Get root access history of one instance.

        """
        url = "/mgmt/instances/%s/root" % base.getid(instance)
        resp, body = self.api.client.get(url)
        if not body:
            raise Exception("Call to " + url + " did not return a body.")
        return RootHistory(self, body['root_enabled_history'])

    def _action(self, instance_id, body):
        """
        Perform a server "action" -- reboot/rebuild/resize/etc.
        """
        url = "/mgmt/instances/%s/action" % instance_id
        resp, body = self.api.client.post(url, body=body)
        check_for_exceptions(resp, body)

    def reboot(self, instance_id):
        """
        Reboot the underlying OS.

        :param instance_id: The :class:`Instance` (or its ID) to share onto.
        """
        body = {'reboot': {}}
        self._action(instance_id, body)