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

# Copyright 2012 IBM
# 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 netaddr
import urllib
import webob.exc

from nova.api.openstack import extensions
from nova.api.openstack import wsgi
from nova.api.openstack import xmlutil
from nova import db
from nova import exception
from nova.openstack.common import cfg
from nova.openstack.common import log as logging

CONF = cfg.CONF
CONF.import_opt('default_floating_pool', 'nova.network.manager')
CONF.import_opt('public_interface', 'nova.network.linux_net')


LOG = logging.getLogger(__name__)
authorize = extensions.extension_authorizer('compute', 'floating_ips_bulk')


class FloatingIPBulkController(object):

    def index(self, req):
        """Return a list of all floating ips"""
        context = req.environ['nova.context']
        authorize(context)

        return self._get_floating_ip_info(context)

    def show(self, req, id):
        """Return a list of all floating ips for a given host"""
        context = req.environ['nova.context']
        authorize(context)

        return self._get_floating_ip_info(context, id)

    def _get_floating_ip_info(self, context, host=None):
        floating_ip_info = {"floating_ip_info": []}

        try:
            if host is None:
                floating_ips = db.floating_ip_get_all(context)
            else:
                floating_ips = db.floating_ip_get_all_by_host(context, host)
        except exception.NoFloatingIpsDefined:
            return floating_ip_info

        for floating_ip in floating_ips:
            instance_uuid = None
            if floating_ip['fixed_ip_id']:
                fixed_ip = db.fixed_ip_get(context, floating_ip['fixed_ip_id'])
                instance_uuid = fixed_ip['instance_uuid']

            result = {'address': floating_ip['address'],
                      'pool': floating_ip['pool'],
                      'interface': floating_ip['interface'],
                      'project_id': floating_ip['project_id'],
                      'instance_uuid': instance_uuid}
            floating_ip_info['floating_ip_info'].append(result)

        return floating_ip_info

    def create(self, req, body):
        """Bulk create floating ips"""
        context = req.environ['nova.context']
        authorize(context)

        if not 'floating_ips_bulk_create' in body:
            raise webob.exc.HTTPUnprocessableEntity()
        params = body['floating_ips_bulk_create']

        LOG.debug(params)

        if not 'ip_range' in params:
            raise webob.exc.HTTPUnprocessableEntity()
        ip_range = params['ip_range']

        pool = params.get('pool', CONF.default_floating_pool)
        interface = params.get('interface', CONF.public_interface)

        try:
            ips = ({'address': str(address),
                    'pool': pool,
                    'interface': interface}
                   for address in self._address_to_hosts(ip_range))
        except exception.InvalidInput as exc:
            raise webob.exc.HTTPBadRequest(explanation=str(exc))

        try:
            db.floating_ip_bulk_create(context, ips)
        except exception.FloatingIpExists as exc:
            raise webob.exc.HTTPBadRequest(explanation=str(exc))

        return {"floating_ips_bulk_create": {"ip_range": ip_range,
                                               "pool": pool,
                                               "interface": interface}}

    def update(self, req, id, body):
        """Bulk delete floating IPs"""
        context = req.environ['nova.context']
        authorize(context)

        if id != "delete":
            raise webob.exc.HTTPNotFound("Unknown action")

        try:
            ip_range = body['ip_range']
        except (TypeError, KeyError):
            raise webob.exc.HTTPUnprocessableEntity()

        try:
            ips = ({'address': str(address)}
                   for address in self._address_to_hosts(ip_range))
        except exception.InvalidInput as exc:
            raise webob.exc.HTTPBadRequest(explanation=str(exc))
        db.floating_ip_bulk_destroy(context, ips)

        return {"floating_ips_bulk_delete": ip_range}

    def _address_to_hosts(self, addresses):
        """
        Iterate over hosts within an address range.

        If an explicit range specifier is missing, the parameter is
        interpreted as a specific individual address.
        """
        try:
            return [netaddr.IPAddress(addresses)]
        except ValueError:
            net = netaddr.IPNetwork(addresses)
            if net.size < 4:
                reason = _("/%s should be specified as single address(es) "
                           "not in cidr format") % net.prefixlen
                raise exception.InvalidInput(reason=reason)
            else:
                return net.iter_hosts()
        except netaddr.AddrFormatError as exc:
            raise exception.InvalidInput(reason=str(exc))


class Floating_ips_bulk(extensions.ExtensionDescriptor):
    """Bulk handling of Floating IPs"""

    name = "FloatingIpsBulk"
    alias = "os-floating-ips-bulk"
    namespace = ("http://docs.openstack.org/compute/ext/"
                 "floating_ips_bulk/api/v2")
    updated = "2012-10-29T13:25:27-06:00"

    def __init__(self, ext_mgr):
        ext_mgr.register(self)

    def get_resources(self):
        resources = []
        resource = extensions.ResourceExtension('os-floating-ips-bulk',
                                                FloatingIPBulkController())
        resources.append(resource)
        return resources
