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

# Copyright 2013 Nicira, 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: Aaron Rosen, Nicira Networks, Inc.


from abc import abstractmethod

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


# For policy.json/Auth
qos_queue_create = "create_qos_queue"
qos_queue_delete = "delete_qos_queue"
qos_queue_get = "get_qos_queue"
qos_queue_list = "get_qos_queues"


class DefaultQueueCreateNotAdmin(qexception.InUse):
    message = _("Need to be admin in order to create queue called default")


class DefaultQueueAlreadyExists(qexception.InUse):
    message = _("Default queue already exists.")


class QueueInvalidDscp(qexception.InvalidInput):
    message = _("Invalid value for dscp %(data)s must be integer.")


class QueueMinGreaterMax(qexception.InvalidInput):
    message = _("Invalid bandwidth rate, min greater than max.")


class QueueInvalidBandwidth(qexception.InvalidInput):
    message = _("Invalid bandwidth rate, %(data)s must be a non negative"
                " integer.")


class MissingDSCPForTrusted(qexception.InvalidInput):
    message = _("No DSCP field needed when QoS workload marked trusted")


class QueueNotFound(qexception.NotFound):
    message = _("Queue %(id)s does not exist")


class QueueInUseByPort(qexception.InUse):
    message = _("Unable to delete queue attached to port.")


class QueuePortBindingNotFound(qexception.NotFound):
    message = _("Port is not associated with lqueue")


def convert_to_unsigned_int_or_none(val):
    if val is None:
        return
    try:
        val = int(val)
        if val < 0:
            raise ValueError
    except (ValueError, TypeError):
        msg = _("'%s' must be a non negative integer.") % val
        raise qexception.InvalidInput(error_message=msg)
    return val

# Attribute Map
RESOURCE_ATTRIBUTE_MAP = {
    'qos_queues': {
        'id': {'allow_post': False, 'allow_put': False,
               'is_visible': True},
        'default': {'allow_post': True, 'allow_put': False,
                    'convert_to': attr.convert_to_boolean,
                    'is_visible': True, 'default': False},
        'name': {'allow_post': True, 'allow_put': False,
                 'validate': {'type:string': None},
                 'is_visible': True, 'default': ''},
        'min': {'allow_post': True, 'allow_put': False,
                'is_visible': True, 'default': '0',
                'convert_to': convert_to_unsigned_int_or_none},
        'max': {'allow_post': True, 'allow_put': False,
                'is_visible': True, 'default': None,
                'convert_to': convert_to_unsigned_int_or_none},
        'qos_marking': {'allow_post': True, 'allow_put': False,
                        'validate': {'type:values': ['untrusted', 'trusted']},
                        'default': 'untrusted', 'is_visible': True},
        'dscp': {'allow_post': True, 'allow_put': False,
                 'is_visible': True, 'default': '0',
                 'convert_to': convert_to_unsigned_int_or_none},
        'tenant_id': {'allow_post': True, 'allow_put': False,
                      'required_by_policy': True,
                      'validate': {'type:string': None},
                      'is_visible': True},
    },
}


QUEUE = 'queue_id'
RXTX_FACTOR = 'rxtx_factor'
EXTENDED_ATTRIBUTES_2_0 = {
    'ports': {
        RXTX_FACTOR: {'allow_post': True,
                      'allow_put': False,
                      'is_visible': False,
                      'default': 1,
                      'convert_to': convert_to_unsigned_int_or_none},

        QUEUE: {'allow_post': False,
                'allow_put': False,
                'is_visible': True,
                'default': False}},
    'networks': {QUEUE: {'allow_post': True,
                         'allow_put': True,
                         'is_visible': True,
                         'default': False}}

}


class Nvp_qos(object):
    """Port Queue extension."""

    @classmethod
    def get_name(cls):
        return "nvp-qos"

    @classmethod
    def get_alias(cls):
        return "nvp-qos"

    @classmethod
    def get_description(cls):
        return "NVP QoS extension."

    @classmethod
    def get_namespace(cls):
        return "http://docs.openstack.org/ext/nvp-qos/api/v2.0"

    @classmethod
    def get_updated(cls):
        return "2012-10-05T10:00:00-00:00"

    @classmethod
    def get_resources(cls):
        """Returns Ext Resources."""
        exts = []
        plugin = manager.QuantumManager.get_plugin()
        resource_name = 'qos_queue'
        collection_name = resource_name.replace('_', '-') + "s"
        params = RESOURCE_ATTRIBUTE_MAP.get(resource_name + "s", dict())
        controller = base.create_resource(collection_name,
                                          resource_name,
                                          plugin, params, allow_bulk=False)

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

        return exts

    def get_extended_resources(self, version):
        if version == "2.0":
            return dict(EXTENDED_ATTRIBUTES_2_0.items() +
                        RESOURCE_ATTRIBUTE_MAP.items())
        else:
            return {}


class QueuePluginBase(object):
    @abstractmethod
    def create_qos_queue(self, context, queue):
        pass

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

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

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