# Copyright 2022-2024 ETSI OSG/SDG TeraFlowSDN (TFS) (https://tfs.etsi.org/)
#
# 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 logging
import threading
from common.tools.kafka.Variables import KafkaConfig, KafkaTopic
from common.proto.kpi_value_api_pb2 import KpiValue
from common.proto.kpi_manager_pb2 import KpiDescriptor, KpiId
from common.Settings import get_service_port_grpc
from common.Constants import ServiceNameEnum
from common.tools.service.GenericGrpcService import GenericGrpcService


from confluent_kafka import KafkaError
from confluent_kafka import Consumer as KafkaConsumer

from kpi_manager.client.KpiManagerClient import KpiManagerClient
# -- test import --
# from kpi_value_writer.tests.test_messages import create_kpi_descriptor_request
from .MetricWriterToPrometheus import MetricWriterToPrometheus


LOGGER           = logging.getLogger(__name__)
ACTIVE_CONSUMERS = []

class KpiValueWriter(GenericGrpcService):
    def __init__(self, cls_name : str = __name__) -> None:
        port = get_service_port_grpc(ServiceNameEnum.KPIVALUEWRITER)
        super().__init__(port, cls_name=cls_name)

    @staticmethod
    def RunKafkaConsumer():
        thread = threading.Thread(target=KpiValueWriter.KafkaConsumer, args=())
        ACTIVE_CONSUMERS.append(thread)
        thread.start()

    @staticmethod
    def KafkaConsumer():
        kpi_manager_client = KpiManagerClient()
        metric_writer      = MetricWriterToPrometheus()

        kafka_consumer  = KafkaConsumer(
            { 'bootstrap.servers' : KafkaConfig.SERVER_IP.value,
              'group.id'          : __class__,
              'auto.offset.reset' : 'latest'}
        )      
        kafka_consumer.subscribe([KafkaTopic.VALUE.value])
        LOGGER.debug("Kafka Consumer start listenng on topic: {:}".format(KafkaTopic.VALUE.value))
        print("Kafka Consumer start listenng on topic: {:}".format(KafkaTopic.VALUE.value))
        while True:
            raw_kpi = kafka_consumer.poll(1.0)
            if raw_kpi is None:
                continue
            elif raw_kpi.error():
                if raw_kpi.error().code() == KafkaError._PARTITION_EOF:
                    continue
                else:
                    print("Consumer error: {}".format(raw_kpi.error()))
                    continue
            try:
                kpi_value = KpiValue()
                kpi_value.ParseFromString(raw_kpi.value())
                LOGGER.info("Received KPI : {:}".format(kpi_value))
                print("Received KPI : {:}".format(kpi_value))
                KpiValueWriter.get_kpi_descriptor(kpi_value, kpi_manager_client, metric_writer)
            except Exception as e:
                print("Error detail: {:}".format(e))
                continue

    @staticmethod
    def get_kpi_descriptor(kpi_value: str, kpi_manager_client, metric_writer):
        print("--- START -----")

        kpi_id = KpiId()
        kpi_id.kpi_id.uuid = kpi_value.kpi_id.kpi_id.uuid
        print("KpiId generated: {:}".format(kpi_id))
        # print("Kpi manger client created: {:}".format(kpi_manager_client))

        try:
            kpi_descriptor_object = KpiDescriptor()
            kpi_descriptor_object = kpi_manager_client.GetKpiDescriptor(kpi_id)
            # TODO: why kpi_descriptor_object recevies a KpiDescriptor type object not Empty type object???
            if kpi_descriptor_object.kpi_id.kpi_id.uuid == kpi_id.kpi_id.uuid:
                LOGGER.info("Extracted KpiDescriptor: {:}".format(kpi_descriptor_object))
                print("Extracted KpiDescriptor: {:}".format(kpi_descriptor_object))
                metric_writer.create_and_expose_cooked_kpi(kpi_descriptor_object, kpi_value)
            else:
                LOGGER.info("No KPI Descriptor found in DB for Kpi ID: {:}".format(kpi_id))
                print("No KPI Descriptor found in DB for Kpi ID: {:}".format(kpi_id))
        except Exception as e:
            LOGGER.info("Unable to get KpiDescriptor. Error: {:}".format(e))
            print ("Unable to get KpiDescriptor. Error: {:}".format(e))