# Copyright (C) 2013 eNovance SAS <licensing@enovance.com>
#
# 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 abc

import six

from neutron._i18n import _
from neutron.api import extensions
from neutron.api.v2 import attributes as attr
from neutron.api.v2 import resource_helper
from neutron.common import exceptions as nexception
from neutron.plugins.common import constants
from neutron.services import service_base


class MeteringLabelNotFound(nexception.NotFound):
    message = _("Metering label %(label_id)s does not exist")


class DuplicateMeteringRuleInPost(nexception.InUse):
    message = _("Duplicate Metering Rule in POST.")


class MeteringLabelRuleNotFound(nexception.NotFound):
    message = _("Metering label rule %(rule_id)s does not exist")


class MeteringLabelRuleOverlaps(nexception.Conflict):
    message = _("Metering label rule with remote_ip_prefix "
                "%(remote_ip_prefix)s overlaps another")


RESOURCE_ATTRIBUTE_MAP = {
    'metering_labels': {
        'id': {'allow_post': False, 'allow_put': False,
               'is_visible': True,
               'primary_key': True},
        'name': {'allow_post': True, 'allow_put': False,
                 'is_visible': True, 'default': ''},
        'description': {'allow_post': True, 'allow_put': False,
                        'is_visible': True, 'default': ''},
        'tenant_id': {'allow_post': True, 'allow_put': False,
                      'required_by_policy': True,
                      'validate': {'type:string': attr.TENANT_ID_MAX_LEN},
                      'is_visible': True},
        'shared': {'allow_post': True, 'allow_put': False,
                   'is_visible': True, 'default': False,
                   'convert_to': attr.convert_to_boolean}
    },
    'metering_label_rules': {
        'id': {'allow_post': False, 'allow_put': False,
               'is_visible': True,
               'primary_key': True},
        'metering_label_id': {'allow_post': True, 'allow_put': False,
                              'validate': {'type:uuid': None},
                              'is_visible': True, 'required_by_policy': True},
        'direction': {'allow_post': True, 'allow_put': False,
                      'is_visible': True,
                      'validate': {'type:values': ['ingress', 'egress']}},
        'excluded': {'allow_post': True, 'allow_put': False,
                     'is_visible': True, 'default': False,
                     'convert_to': attr.convert_to_boolean},
        'remote_ip_prefix': {'allow_post': True, 'allow_put': False,
                             'is_visible': True, 'required_by_policy': True,
                             'validate': {'type:subnet': None}},
        'tenant_id': {'allow_post': True, 'allow_put': False,
                      'required_by_policy': True,
                      'validate': {'type:string': attr.TENANT_ID_MAX_LEN},
                      'is_visible': True}
    }
}


class Metering(extensions.ExtensionDescriptor):

    @classmethod
    def get_name(cls):
        return "Neutron Metering"

    @classmethod
    def get_alias(cls):
        return "metering"

    @classmethod
    def get_description(cls):
        return "Neutron Metering extension."

    @classmethod
    def get_updated(cls):
        return "2013-06-12T10:00:00-00:00"

    @classmethod
    def get_plugin_interface(cls):
        return MeteringPluginBase

    @classmethod
    def get_resources(cls):
        """Returns Ext Resources."""
        plural_mappings = resource_helper.build_plural_mappings(
            {}, RESOURCE_ATTRIBUTE_MAP)
        attr.PLURALS.update(plural_mappings)
        # PCM: Metering sets pagination and sorting to True. Do we have cfg
        # entries for these so can be read? Else, must pass in.
        return resource_helper.build_resource_info(plural_mappings,
                                                   RESOURCE_ATTRIBUTE_MAP,
                                                   constants.METERING,
                                                   translate_name=True,
                                                   allow_bulk=True)

    def update_attributes_map(self, attributes):
        super(Metering, self).update_attributes_map(
            attributes, extension_attrs_map=RESOURCE_ATTRIBUTE_MAP)

    def get_extended_resources(self, version):
        if version == "2.0":
            return RESOURCE_ATTRIBUTE_MAP
        else:
            return {}


@six.add_metaclass(abc.ABCMeta)
class MeteringPluginBase(service_base.ServicePluginBase):

    def get_plugin_description(self):
        return constants.METERING

    def get_plugin_type(self):
        return constants.METERING

    @abc.abstractmethod
    def create_metering_label(self, context, metering_label):
        """Create a metering label."""
        pass

    @abc.abstractmethod
    def delete_metering_label(self, context, label_id):
        """Delete a metering label."""
        pass

    @abc.abstractmethod
    def get_metering_label(self, context, label_id, fields=None):
        """Get a metering label."""
        pass

    @abc.abstractmethod
    def get_metering_labels(self, context, filters=None, fields=None,
                            sorts=None, limit=None, marker=None,
                            page_reverse=False):
        """List all metering labels."""
        pass

    @abc.abstractmethod
    def create_metering_label_rule(self, context, metering_label_rule):
        """Create a metering label rule."""
        pass

    @abc.abstractmethod
    def get_metering_label_rule(self, context, rule_id, fields=None):
        """Get a metering label rule."""
        pass

    @abc.abstractmethod
    def delete_metering_label_rule(self, context, rule_id):
        """Delete a metering label rule."""
        pass

    @abc.abstractmethod
    def get_metering_label_rules(self, context, filters=None, fields=None,
                                 sorts=None, limit=None, marker=None,
                                 page_reverse=False):
        """List all metering label rules."""
        pass
