# SPDX-FileCopyrightText: 2020 The Magma Authors.
# SPDX-FileCopyrightText: 2022 Open Networking Foundation <support@opennetworking.org>
#
# SPDX-License-Identifier: BSD-3-Clause

import json
import logging
import socket
from contextlib import closing
from typing import Any, Dict

import grpc
import jsonschema
from common.rpc_utils import return_void
from eventd.event_validator import EventValidator
from orc8r.protos import eventd_pb2, eventd_pb2_grpc

RETRY_ON_FAILURE = 'retry_on_failure'


class EventDRpcServicer(eventd_pb2_grpc.EventServiceServicer):
    """
    gRPC based server for EventD.
    """

    def __init__(self, config: Dict[str, Any], validator: EventValidator):
        self._fluent_bit_port = config['fluent_bit_port']
        self._tcp_timeout = config['tcp_timeout']
        self._event_registry = config['event_registry']
        self._validator = validator

    def add_to_server(self, server):
        """
        Add the servicer to a gRPC server
        """
        eventd_pb2_grpc.add_EventServiceServicer_to_server(self, server)

    @return_void
    def LogEvent(self, request: eventd_pb2.Event, context):
        """
        Logs an event.
        """
        logging.debug("Logging event: %s", request)

        try:
            self._validator.validate_event(request.value, request.event_type)
        except (KeyError, jsonschema.ValidationError) as e:
            logging.error("KeyError for log: %s. Error: %s", request, e)
            context.set_code(grpc.StatusCode.INVALID_ARGUMENT)
            context.set_details(
                'Event validation failed, Details: {}'.format(e),
            )
            return

        value = {
            'stream_name': request.stream_name,
            'event_type': request.event_type,
            'event_tag': request.tag,
            'value': request.value,
            'retry_on_failure': self._needs_retries(request.event_type),
        }
        try:
            with closing(
                socket.create_connection(
                ('localhost', self._fluent_bit_port),
                timeout=self._tcp_timeout,
                ),
            ) as sock:
                logging.debug('Sending log to FluentBit')
                sock.sendall(json.dumps(value).encode('utf-8'))
        except socket.error as e:
            logging.error('Connection to FluentBit failed: %s', e)
            logging.info(
                'FluentBit (td-agent-bit) may not be enabled '
                'or configured correctly',
            )
            context.set_code(grpc.StatusCode.UNAVAILABLE)
            context.set_details(
                'Could not connect to FluentBit locally, Details: {}'
                .format(e),
            )
            return

        logging.debug("Successfully logged event: %s", request)

    def _needs_retries(self, event_type: str) -> str:
        if event_type not in self._event_registry:
            # Should not get here
            return 'False'
        if RETRY_ON_FAILURE not in self._event_registry[event_type]:
            return 'False'
        return str(self._event_registry[event_type][RETRY_ON_FAILURE])