"""
# vim: tabstop=4 shiftwidth=4 softtabstop=4
#
# Copyright 2012 Nicira Networks, Inc.  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.
#
# @author: Dan Wendlandt, Nicira, Inc
#
"""

from abc import abstractmethod

from quantum.api.v2 import attributes as attr
from quantum.api.v2 import base
from quantum.common import exceptions as qexception
from quantum.extensions import extensions
from quantum import manager
from quantum.openstack.common import cfg
from quantum import quota


# L3 Exceptions
class RouterNotFound(qexception.NotFound):
    message = _("Router %(router_id)s could not be found")


class RouterInUse(qexception.InUse):
    message = _("Router %(router_id)s still has active ports")


class FloatingIPNotFound(qexception.NotFound):
    message = _("Floating IP %(floatingip_id)s could not be found")


class ExternalGatewayForFloatingIPNotFound(qexception.NotFound):
    message = _("Could not find an external network gateway reachable "
                "from subnet %(subnet_id)s.  Therefore, cannot associate "
                "Port %(port_id)s with a Floating IP.")


class FloatingIPPortAlreadyAssociated(qexception.InUse):
    message = _("Port %(port_id) already has a floating IP associated with it")


def _validate_uuid_or_none(data, valid_values=None):
    if data is None:
        return None
    return attr._validate_regex(data, attr.UUID_PATTERN)

attr.validators['type:uuid_or_none'] = _validate_uuid_or_none

# Attribute Map
RESOURCE_ATTRIBUTE_MAP = {
    'routers': {
        'id': {'allow_post': False, 'allow_put': False,
               'validate': {'type:regex': attr.UUID_PATTERN},
               'is_visible': True},
        'name': {'allow_post': True, 'allow_put': True,
                 'is_visible': True, 'default': ''},
        'admin_state_up': {'allow_post': True, 'allow_put': True,
                           'default': True,
                           'convert_to': attr.convert_to_boolean,
                           'validate': {'type:boolean': None},
                           'is_visible': True},
        'status': {'allow_post': False, 'allow_put': False,
                   'is_visible': True},
        'tenant_id': {'allow_post': True, 'allow_put': False,
                      'required_by_policy': True,
                      'is_visible': True},
        'external_gateway_info': {'allow_post': True, 'allow_put': True,
                                  'is_visible': True, 'default': None}
    },
    'floatingips': {
        'id': {'allow_post': False, 'allow_put': False,
               'is_visible': True},
        'floating_ip_address': {'allow_post': False, 'allow_put': False,
                                'is_visible': True},
        'floating_network_id': {'allow_post': True, 'allow_put': False,
                                'validate': {'type:regex': attr.UUID_PATTERN},
                                'is_visible': True},
        'router_id': {'allow_post': False, 'allow_put': False,
                      'is_visible': True, 'default': None},
        'port_id': {'allow_post': True, 'allow_put': True,
                    'validate': {'type:uuid_or_none': None},
                    'is_visible': True, 'default': None},
        'fixed_ip_address': {'allow_post': True, 'allow_put': True,
                             'validate': {'type:ip_address_or_none': None},
                             'is_visible': True, 'default': None},
        'tenant_id': {'allow_post': True, 'allow_put': False,
                      'required_by_policy': True,
                      'is_visible': True}
    },
}

l3_quota_opts = [
    cfg.IntOpt('quota_router',
               default=10,
               help='number of routers allowed per tenant, -1 for unlimited'),
    cfg.IntOpt('quota_floatingip',
               default=50,
               help='number of floating IPs allowed per tenant, '
                    '-1 for unlimited'),
]
cfg.CONF.register_opts(l3_quota_opts, 'QUOTAS')


class L3(object):

    @classmethod
    def get_name(cls):
        return "Quantum Router"

    @classmethod
    def get_alias(cls):
        return "os-quantum-router"

    @classmethod
    def get_description(cls):
        return ("Router abstraction for basic L3 forwarding"
                " between L2 Quantum networks and access to external"
                " networks via a NAT gateway.")

    @classmethod
    def get_namespace(cls):
        return "http://docs.openstack.org/ext/os-quantum-router/api/v1.0"

    @classmethod
    def get_updated(cls):
        return "2012-07-20T10:00:00-00:00"

    @classmethod
    def get_resources(cls):
        """ Returns Ext Resources """
        exts = []
        plugin = manager.QuantumManager.get_plugin()
        for resource_name in ['router', 'floatingip']:
            collection_name = resource_name + "s"
            params = RESOURCE_ATTRIBUTE_MAP.get(collection_name, dict())

            member_actions = {}
            if resource_name == 'router':
                member_actions = {'add_router_interface': 'PUT',
                                  'remove_router_interface': 'PUT'}

            quota.QUOTAS.register_resource_by_name(resource_name)

            controller = base.create_resource(collection_name,
                                              resource_name,
                                              plugin, params,
                                              member_actions=member_actions)

            ex = extensions.ResourceExtension(collection_name,
                                              controller,
                                              member_actions=member_actions)
            exts.append(ex)

        return exts


class RouterPluginBase(object):

    @abstractmethod
    def create_router(self, context, router):
        pass

    @abstractmethod
    def update_router(self, context, id, router):
        pass

    @abstractmethod
    def get_router(self, context, id, fields=None):
        pass

    @abstractmethod
    def delete_router(self, context, id):
        pass

    @abstractmethod
    def get_routers(self, context, filters=None, fields=None):
        pass

    @abstractmethod
    def add_router_interface(self, context, router_id, interface_info):
        pass

    @abstractmethod
    def remove_router_interface(self, context, router_id, interface_info):
        pass

    @abstractmethod
    def create_floatingip(self, context, floatingip):
        pass

    @abstractmethod
    def update_floatingip(self, context, id, floatingip):
        pass

    @abstractmethod
    def get_floatingip(self, context, id, fields=None):
        pass

    @abstractmethod
    def delete_floatingip(self, context, id):
        pass

    @abstractmethod
    def get_floatingips(self, context, filters=None, fields=None):
        pass
