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

# Copyright 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.

""" Keypair management extension"""

import webob
import webob.exc

from nova.api.openstack import extensions
from nova.api.openstack import wsgi
from nova.api.openstack import xmlutil
from nova.compute import api as compute_api
from nova import exception


authorize = extensions.extension_authorizer('compute', 'keypairs')


class KeypairTemplate(xmlutil.TemplateBuilder):
    def construct(self):
        return xmlutil.MasterTemplate(xmlutil.make_flat_dict('keypair'), 1)


class KeypairsTemplate(xmlutil.TemplateBuilder):
    def construct(self):
        root = xmlutil.TemplateElement('keypairs')
        elem = xmlutil.make_flat_dict('keypair', selector='keypairs',
                                      subselector='keypair')
        root.append(elem)

        return xmlutil.MasterTemplate(root, 1)


class KeypairController(object):

    """ Keypair API controller for the OpenStack API """
    def __init__(self):
        self.api = compute_api.KeypairAPI()

    @wsgi.serializers(xml=KeypairTemplate)
    def create(self, req, body):
        """
        Create or import keypair.

        Sending name will generate a key and return private_key
        and fingerprint.

        You can send a public_key to add an existing ssh key

        params: keypair object with:
            name (required) - string
            public_key (optional) - string
        """

        context = req.environ['nova.context']
        authorize(context)
        params = body['keypair']
        name = params['name']

        try:
            if 'public_key' in params:
                keypair = self.api.import_key_pair(context,
                                              context.user_id, name,
                                              params['public_key'])
            else:
                keypair = self.api.create_key_pair(context, context.user_id,
                                                   name)

            return {'keypair': keypair}

        except exception.KeypairLimitExceeded:
            msg = _("Quota exceeded, too many key pairs.")
            raise webob.exc.HTTPRequestEntityTooLarge(
                        explanation=msg,
                        headers={'Retry-After': 0})
        except exception.InvalidKeypair:
            msg = _("Keypair data is invalid")
            raise webob.exc.HTTPBadRequest(explanation=msg)
        except exception.KeyPairExists:
            msg = _("Key pair '%s' already exists.") % name
            raise webob.exc.HTTPConflict(explanation=msg)

    def delete(self, req, id):
        """
        Delete a keypair with a given name
        """
        context = req.environ['nova.context']
        authorize(context)
        try:
            self.api.delete_key_pair(context, context.user_id, id)
        except exception.KeypairNotFound:
            raise webob.exc.HTTPNotFound()
        return webob.Response(status_int=202)

    @wsgi.serializers(xml=KeypairsTemplate)
    def index(self, req):
        """
        List of keypairs for a user
        """
        context = req.environ['nova.context']
        authorize(context)
        key_pairs = self.api.get_key_pairs(context, context.user_id)
        rval = []
        for key_pair in key_pairs:
            rval.append({'keypair': {
                'name': key_pair['name'],
                'public_key': key_pair['public_key'],
                'fingerprint': key_pair['fingerprint'],
            }})

        return {'keypairs': rval}


class Keypairs(extensions.ExtensionDescriptor):
    """Keypair Support"""

    name = "Keypairs"
    alias = "os-keypairs"
    namespace = "http://docs.openstack.org/compute/ext/keypairs/api/v1.1"
    updated = "2011-08-08T00:00:00+00:00"

    def get_resources(self):
        resources = []

        res = extensions.ResourceExtension(
                'os-keypairs',
                KeypairController())

        resources.append(res)
        return resources
