import asyncio
import argparse
import logging

import grpc
import api

from agent import AgentApi

def get_arg_parser() -> argparse.ArgumentParser:
    parser = argparse.ArgumentParser(
                    prog="sys-mon-agent",
                    description="Launch the Home Assistant integrated system monitoring agent.")
    
    parser.add_argument("-p", "--port", type=int, default=8202)
    parser.add_argument("-a", "--address", type=str, default="[::]")
    parser.add_argument("--ssl-cert", type=argparse.FileType("rb"), dest="cert")
    parser.add_argument("--ssl-cert-key", type=argparse.FileType("rb"), dest="cert_key")

    return parser

def configure_server_port(server: grpc.Server, arguments) -> grpc.Server:
    address_str = f"{arguments.address}:{arguments.port}"

    if arguments.cert and arguments.cert_key:
        cert_data = arguments.cert.read()
        cert_key_data = arguments.cert_key.read()
    
        credentials = grpc.ssl_server_credentials(((cert_data, cert_key_data)))
        
        logging.info("Listening to secure port on %s.", address_str)
        server.add_secure_port(address_str, credentials)
    else:
        logging.info("Listening to insecure port on %s.", address_str)
        server.add_insecure_port(address_str)

    return server
    

async def main() -> None:
    args = get_arg_parser().parse_args()
    server = grpc.aio.server()

    api.add_AgentServicer_to_server(AgentApi(), server)
    
    server = configure_server_port(server, args)
    
    logging.info("Starting server...")

    await server.start()

    await server.wait_for_termination()



if __name__ == "__main__":
    logging.basicConfig(level=logging.INFO)
    loop = asyncio.new_event_loop()

    try:
        loop.run_until_complete(main())
    finally:
        loop.close()