# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright (c) 2010 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.

"""Console Proxy Service."""

import socket

from nova.compute import rpcapi as compute_rpcapi
from nova import exception
from nova import flags
from nova import manager
from nova.openstack.common import cfg
from nova.openstack.common import importutils
from nova.openstack.common import log as logging
from nova import utils


console_manager_opts = [
    cfg.StrOpt('console_driver',
               default='nova.console.xvp.XVPConsoleProxy',
               help='Driver to use for the console proxy'),
    cfg.BoolOpt('stub_compute',
                default=False,
                help='Stub calls to compute worker for tests'),
    cfg.StrOpt('console_public_hostname',
               default=socket.gethostname(),
               help='Publicly visible name for this console host'),
    ]

FLAGS = flags.FLAGS
FLAGS.register_opts(console_manager_opts)
LOG = logging.getLogger(__name__)


class ConsoleProxyManager(manager.Manager):
    """Sets up and tears down any console proxy connections.

    Needed for accessing instance consoles securely.

    """

    RPC_API_VERSION = '1.0'

    def __init__(self, console_driver=None, *args, **kwargs):
        if not console_driver:
            console_driver = FLAGS.console_driver
        self.driver = importutils.import_object(console_driver)
        super(ConsoleProxyManager, self).__init__(*args, **kwargs)
        self.driver.host = self.host
        self.compute_rpcapi = compute_rpcapi.ComputeAPI()

    def init_host(self):
        self.driver.init_host()

    @exception.wrap_exception()
    def add_console(self, context, instance_id, password=None,
                    port=None, **kwargs):
        instance = self.db.instance_get(context, instance_id)
        host = instance['host']
        name = instance['name']
        pool = self.get_pool_for_instance_host(context, host)
        try:
            console = self.db.console_get_by_pool_instance(context,
                                                           pool['id'],
                                                           instance['uuid'])
        except exception.NotFound:
            LOG.debug(_('Adding console'), instance=instance)
            if not password:
                password = utils.generate_password(8)
            if not port:
                port = self.driver.get_port(context)
            console_data = {'instance_name': name,
                            'instance_uuid': instance['uuid'],
                            'password': password,
                            'pool_id': pool['id']}
            if port:
                console_data['port'] = port
            console = self.db.console_create(context, console_data)
            self.driver.setup_console(context, console)

        return console['id']

    @exception.wrap_exception()
    def remove_console(self, context, console_id, **_kwargs):
        try:
            console = self.db.console_get(context, console_id)
        except exception.NotFound:
            LOG.debug(_('Tried to remove non-existant console '
                            '%(console_id)s.') %
                            {'console_id': console_id})
            return
        self.db.console_delete(context, console_id)
        self.driver.teardown_console(context, console)

    def get_pool_for_instance_host(self, context, instance_host):
        context = context.elevated()
        console_type = self.driver.console_type
        try:
            pool = self.db.console_pool_get_by_host_type(context,
                                                         instance_host,
                                                         self.host,
                                                         console_type)
        except exception.NotFound:
            #NOTE(mdragon): Right now, the only place this info exists is the
            #               compute worker's flagfile, at least for
            #               xenserver. Thus we ned to ask.
            if FLAGS.stub_compute:
                pool_info = {'address': '127.0.0.1',
                             'username': 'test',
                             'password': '1234pass'}
            else:
                pool_info = compute_rpcapi.get_console_pool_info(context,
                        console_type, instance_host)
            pool_info['password'] = self.driver.fix_pool_password(
                                                    pool_info['password'])
            pool_info['host'] = self.host
            pool_info['public_hostname'] = FLAGS.console_public_hostname
            pool_info['console_type'] = self.driver.console_type
            pool_info['compute_host'] = instance_host
            pool = self.db.console_pool_create(context, pool_info)
        return pool
