# Copyright 2021-2023 H2020 TeraFlow (https://www.teraflow-h2020.eu/)
#
# 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 grpc, json, logging
from common.rpc_method_wrapper.Decorator import create_metrics, safe_and_metered_rpc_method
from context.client.ContextClient import ContextClient
from context.proto.context_pb2 import (
    ConfigActionEnum, Empty, Service, ServiceStatusEnum, ServiceTypeEnum, Slice, SliceId, SliceStatusEnum)
from interdomain.client.InterdomainClient import InterdomainClient
from service.client.ServiceClient import ServiceClient
from slice.proto.slice_pb2_grpc import SliceServiceServicer

LOGGER = logging.getLogger(__name__)

SERVICE_NAME = 'Slice'
METHOD_NAMES = ['CreateSlice', 'UpdateSlice', 'DeleteSlice']
METRICS = create_metrics(SERVICE_NAME, METHOD_NAMES)

class SliceServiceServicerImpl(SliceServiceServicer):
    def __init__(
        self, context_client : ContextClient, interdomain_client : InterdomainClient, service_client : ServiceClient
    ):
        LOGGER.debug('Creating Servicer...')
        self.context_client = context_client
        self.interdomain_client = interdomain_client
        self.service_client = service_client
        LOGGER.debug('Servicer Created')

    def create_update(self, request : Slice) -> SliceId:
        slice_id = self.context_client.SetSlice(request)
        if len(request.slice_endpoint_ids) != 2: return slice_id

        domains = set()
        for slice_endpoint_id in request.slice_endpoint_ids:
            device_uuid = slice_endpoint_id.device_id.device_uuid.uuid
            domains.add(device_uuid.split('@')[1])

        is_multi_domain = len(domains) == 2
        if is_multi_domain:
            slice_id = self.interdomain_client.RequestSlice(request)
        else:
            # pylint: disable=no-member
            service_request = Service()
            service_request.service_id.context_id.context_uuid.uuid = request.slice_id.context_id.context_uuid.uuid
            service_request.service_id.service_uuid.uuid = request.slice_id.slice_uuid.uuid
            service_request.service_type = ServiceTypeEnum.SERVICETYPE_L3NM
            service_request.service_status.service_status = ServiceStatusEnum.SERVICESTATUS_PLANNED

            service_reply = self.service_client.CreateService(service_request)
            if service_reply != service_request.service_id: # pylint: disable=no-member
                raise Exception('Service creation failed. Wrong Service Id was returned')

            config_rule = service_request.service_config.config_rules.add()
            config_rule.action = ConfigActionEnum.CONFIGACTION_SET
            config_rule.resource_key = '/settings'
            config_rule.resource_value = json.dumps(
                {'mtu': 1512, 'address_families': ['IPV4'], 'bgp_as': 65000, 'bgp_route_target': '65000:333'},
                sort_keys=True)

            for slice_endpoint_id in request.slice_endpoint_ids:
                device_uuid = slice_endpoint_id.device_id.device_uuid.uuid
                endpoint_uuid = slice_endpoint_id.endpoint_uuid.uuid

                endpoint_id = service_request.service_endpoint_ids.add()
                endpoint_id.device_id.device_uuid.uuid = device_uuid
                endpoint_id.endpoint_uuid.uuid = endpoint_uuid

                config_rule = service_request.service_config.config_rules.add()
                config_rule.action = ConfigActionEnum.CONFIGACTION_SET
                config_rule.resource_key = '/device[{:s}]/endpoint[{:s}]/settings'.format(device_uuid, endpoint_uuid)
                config_rule.resource_value = json.dumps(
                    {'router_id': '0.0.0.0', 'route_distinguisher': '0:0', 'sub_interface_index': 0, 'vlan_id': 0,
                     'address_ip': '0.0.0.0', 'address_prefix': 0},
                    sort_keys=True)

            service_reply = self.service_client.UpdateService(service_request)
            if service_reply != service_request.service_id: # pylint: disable=no-member
                raise Exception('Service update failed. Wrong Service Id was returned')

            reply = Slice()
            reply.CopyFrom(request)
            slice_service_id = reply.slice_service_ids.add()
            slice_service_id.CopyFrom(service_reply)
            self.context_client.SetSlice(reply)
            slice_id = reply.slice_id

        slice_ = self.context_client.GetSlice(slice_id)
        slice_active = Slice()
        slice_active.CopyFrom(slice_)
        slice_active.slice_status.slice_status = SliceStatusEnum.SLICESTATUS_ACTIVE
        self.context_client.SetSlice(slice_active)
        return slice_id

    @safe_and_metered_rpc_method(METRICS, LOGGER)
    def CreateSlice(self, request : Slice, context : grpc.ServicerContext) -> SliceId:
        #try:
        #    slice_ = self.context_client.GetSlice(request.slice_id)
        #    slice_id = slice_.slice_id
        #except grpc.RpcError:
        #    slice_id = self.context_client.SetSlice(request)
        #return slice_id
        return self.create_update(request)

    @safe_and_metered_rpc_method(METRICS, LOGGER)
    def UpdateSlice(self, request : Slice, context : grpc.ServicerContext) -> SliceId:
        #slice_id = self.context_client.SetSlice(request)
        #if len(request.slice_endpoint_ids) != 2: return slice_id
        #
        #domains = set()
        #for slice_endpoint_id in request.slice_endpoint_ids:
        #    device_uuid = slice_endpoint_id.device_id.device_uuid.uuid
        #    domains.add(device_uuid.split('@')[0])
        #
        #is_multi_domain = len(domains) == 2
        #if is_multi_domain:
        #    return self.interdomain_client.LookUpSlice(request)
        #else:
        #    raise NotImplementedError('Slice should create local services for single domain slice')
        return self.create_update(request)

    @safe_and_metered_rpc_method(METRICS, LOGGER)
    def DeleteSlice(self, request : SliceId, context : grpc.ServicerContext) -> Empty:
        return Empty()