# Copyright 2014
# The Cloudscaling Group, Inc.
#
# 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 keystoneclient.v2_0 import client as kc
from novaclient import client as novaclient
from novaclient import shell as novashell
from oslo.config import cfg
from oslo import messaging

from ec2api import context as ec2_context
from ec2api.openstack.common.gettextutils import _
from ec2api.openstack.common import log as logging

logger = logging.getLogger(__name__)

CONF = cfg.CONF


try:
    from neutronclient.v2_0 import client as neutronclient
except ImportError:
    neutronclient = None
    logger.info(_('neutronclient not available'))
try:
    from cinderclient import client as cinderclient
except ImportError:
    cinderclient = None
    logger.info(_('cinderclient not available'))
try:
    from glanceclient import client as glanceclient
except ImportError:
    glanceclient = None
    logger.info(_('glanceclient not available'))


def nova(context, service_type='compute'):
    computeshell = novashell.OpenStackComputeShell()
    extensions = computeshell._discover_extensions("1.1")

    args = {
        'project_id': context.project_id,
        'auth_url': CONF.keystone_url,
        'service_type': service_type,
        'username': None,
        'api_key': None,
        'extensions': extensions,
    }

    client = novaclient.Client(1.1, **args)

    management_url = _url_for(context, service_type=service_type)
    client.client.auth_token = context.auth_token
    client.client.management_url = management_url

    return client


def neutron(context):
    if neutronclient is None:
        return None

    args = {
        'auth_url': CONF.keystone_url,
        'service_type': 'network',
        'token': context.auth_token,
        'endpoint_url': _url_for(context, service_type='network'),
    }

    return neutronclient.Client(**args)


def glance(context):
    if glanceclient is None:
        return None

    args = {
        'auth_url': CONF.keystone_url,
        'service_type': 'image',
        'token': context.auth_token,
    }

    return glanceclient.Client(
        "1", endpoint=_url_for(context, service_type='image'), **args)


def cinder(context):
    if cinderclient is None:
        return nova(context, 'volume')

    args = {
        'service_type': 'volume',
        'auth_url': CONF.keystone_url,
        'username': None,
        'api_key': None,
    }

    _cinder = cinderclient.Client('1', **args)
    management_url = _url_for(context, service_type='volume')
    _cinder.client.auth_token = context.auth_token
    _cinder.client.management_url = management_url

    return _cinder


def keystone(context):
    _keystone = kc.Client(
        token=context.auth_token,
        tenant_id=context.project_id,
        auth_url=CONF.keystone_url)

    return _keystone


def nova_cert(context):
    _cert_api = _rpcapi_CertAPI(context)
    return _cert_api


def rpc_init(conf):
    global _rpc_TRANSPORT
    # NOTE(ft): set control_exchange parameter to use Nova cert topic
    messaging.set_transport_defaults('nova')
    _rpc_TRANSPORT = messaging.get_transport(conf)


def _url_for(context, **kwargs):
    service_catalog = context.service_catalog
    if not service_catalog:
        catalog = keystone(context).service_catalog.catalog
        service_catalog = catalog["serviceCatalog"]
        context.service_catalog = service_catalog

    service_type = kwargs["service_type"]
    for service in service_catalog:
        if service["type"] != service_type:
            continue
        for endpoint in service["endpoints"]:
            if "publicURL" in endpoint:
                return endpoint["publicURL"]
        else:
            return None

    return None


class _rpcapi_CertAPI(object):
    '''Client side of the cert rpc API.'''

    def __init__(self, context):
        super(_rpcapi_CertAPI, self).__init__()
        target = messaging.Target(topic=CONF.cert_topic, version='2.0')
        self.client = _rpc_get_client(target)
        self.context = context

    def decrypt_text(self, text):
        cctxt = self.client.prepare()
        return cctxt.call(self.context, 'decrypt_text',
                          project_id=self.context.project_id,
                          text=text)


_rpc_TRANSPORT = None


def _rpc_get_client(target):
    assert _rpc_TRANSPORT is not None
    serializer = _rpc_RequestContextSerializer()
    return messaging.RPCClient(_rpc_TRANSPORT,
                               target,
                               serializer=serializer)


class _rpc_RequestContextSerializer(messaging.NoOpSerializer):

    def serialize_context(self, context):
        return context.to_dict()

    def deserialize_context(self, context):
        return ec2_context.RequestContext.from_dict(context)