#!/usr/bin/env python3
# SPDX-License-Identifier: BSD-3-Clause OR Apache-2.0
# encoding: utf-8

"""Simple debug tool to log FIB updates issued by µD3TN."""

import argparse
import logging
import sys

from ud3tn_utils.aap2 import (
    AAP2UnixClient,
    AAP2TCPClient,
    AAP2ServerDisconnected,
    AuthType,
    LinkStatus,
    ResponseStatus,
)
from ud3tn_utils.aap2.bin.helpers import (
    add_common_parser_arguments,
    add_keepalive_parser_argument,
    get_secret_from_args,
    initialize_logger,
)


logger = logging.getLogger(__name__)


def run_fib_logger(aap2_client):
    logger.info("Waiting for FIB events...")

    while True:
        try:
            msg = aap2_client.receive_msg()
        except AAP2ServerDisconnected:
            logger.warning("µD3TN has closed the connection.")
            sys.exit(1)
        except KeyboardInterrupt:
            logger.info("Terminated by keyboard interrupt.")
            sys.exit(130)  # exit status for SIGINT

        if msg.WhichOneof("msg") == "link":
            logger.warning(
                "%s: %s%s",
                {
                    LinkStatus.LINK_STATUS_UNSPECIFIED: "CONNECTING",
                    LinkStatus.LINK_STATUS_UP: "UP",
                    LinkStatus.LINK_STATUS_DOWN: "DOWN",
                }.get(msg.link.status, f"(status={msg.link.status})"),
                (
                    f"{msg.link.peer_node_id} via "
                    if msg.link.peer_node_id else ""
                ),
                msg.link.peer_cla_addr,
            )
            aap2_client.send_response_status(
                ResponseStatus.RESPONSE_STATUS_SUCCESS,
            )
        else:
            if msg.WhichOneof("msg") != "keepalive":
                logger.warning(
                    "Received unhandled '%s' message discarding.",
                    msg.WhichOneof("msg"),
                )
            # ACK the message in any case -- same response KA, unhandled
            aap2_client.send_response_status(
                ResponseStatus.RESPONSE_STATUS_ACK,
            )


def main():
    parser = argparse.ArgumentParser(
        description="FIB update logger for µD3TN",
    )
    add_common_parser_arguments(parser)
    add_keepalive_parser_argument(parser)
    args = parser.parse_args()

    global logger
    logger = initialize_logger(args.verbosity)

    if args.tcp:
        aap2_client = AAP2TCPClient(address=args.tcp)
    else:
        aap2_client = AAP2UnixClient(address=args.socket)

    with aap2_client:
        secret = aap2_client.configure(
            args.agentid,
            subscribe=True,
            secret=get_secret_from_args(args),
            auth_type=AuthType.AUTH_TYPE_FIB_CONTROL,
            keepalive_seconds=args.keepalive_seconds,
        )
        logger.info("AAP 2.0 agent configured as FIB subscriber!")
        logger.debug("Assigned agent secret: '%s'", secret)
        run_fib_logger(aap2_client)


if __name__ == "__main__":
    main()