async fn main() -> anyhow::Result<()> {

    let args = Args::parse();

    tracing_subscriber::registry()

        .with(fmt::layer())

        .with(EnvFilter::from_default_env())

        .init();

    let config = toml::from_str::<roowho2_lib::server::config::Config>(

        &std::fs::read_to_string(&args.config_path).context(format!(

        ))?,

    )?;

    let fd_map: HashMap<String, OwnedFd> = HashMap::from_iter(

        sd_notify::listen_fds_with_names(false)?.map(|(fd_num, name)| {

            (

                name.clone(),

                // SAFETY: please don't mess around with file descriptors in random places

                //         around the codebase lol

                unsafe { std::os::fd::OwnedFd::from_raw_fd(fd_num) },

            )

        }),

    let mut join_set = tokio::task::JoinSet::new();

    let whod_status_store = Arc::new(RwLock::new(HashMap::new()));

    let client_server_token = CancellationToken::new();

    let client_server_token_ = client_server_token.clone();

    tokio::spawn(async move {

        client_server_token_.cancelled().await;

        tracing::info!("RWHOD client-server is now accepting connections");

        sd_notify::notify(true, &[sd_notify::NotifyState::Ready]).ok();

        Ok::<(), anyhow::Error>(())

    });

    if config.rwhod.enable {

        tracing::info!("Starting RWHOD server");

        let socket = fd_map

            .get("rwhod_socket")

            .map(|fd| {

                let std_socket = unsafe { std::net::UdpSocket::from_raw_fd(fd.as_raw_fd()) };

                std_socket.set_nonblocking(true)?;

                UdpSocket::from_std(std_socket)

            })

            .context("RWHOD server is enabled, but socket fd not provided by systemd")??;

        join_set.spawn(rwhod_server(socket, whod_status_store.clone()));

        tracing::debug!("RWHOD server is disabled in configuration");

    join_set.spawn(client_server(

        fd_map

            .get("client_socket")

            .context("RWHOD client-server socket fd not provided by systemd")?

            .try_clone()

            .context("Failed to clone RWHOD client-server socket fd")?,

        whod_status_store.clone(),

        client_server_token,

    join_set.spawn(ctrl_c_handler());

    join_set.join_next().await.unwrap()??;

    Ok(())

}

async fn ctrl_c_handler() -> anyhow::Result<()> {

    tokio::signal::ctrl_c()

        .await

        .map_err(|e| anyhow::anyhow!("Failed to listen for Ctrl-C: {}", e))

}

async fn rwhod_server(

    socket: UdpSocket,

    whod_status_store: RwhodStatusStore,

) -> anyhow::Result<()> {

    let socket = Arc::new(socket);

    let interfaces = roowho2_lib::server::rwhod::determine_relevant_interfaces()?;

    let sender_task = rwhod_packet_sender_task(socket.clone(), interfaces);

    let receiver_task = rwhod_packet_receiver_task(socket.clone(), whod_status_store);

    tokio::select! {

        res = sender_task => res?,

        res = receiver_task => res?,

    Ok(())

}

async fn client_server(

    socket_fd: OwnedFd,

    whod_status_store: RwhodStatusStore,

    startup_token: CancellationToken,

) -> anyhow::Result<()> {

    let std_socket =

        unsafe { std::os::unix::net::UnixListener::from_raw_fd(socket_fd.as_raw_fd()) };

    std_socket.set_nonblocking(true)?;

    let zlink_listener = zlink::unix::Listener::try_from(OwnedFd::from(std_socket))?;

    let client_server_task = varlink_client_server_task(zlink_listener, whod_status_store);

    startup_token.cancel();

    client_server_task.await?;

    Ok(())

}