use std::time::Duration;

use serde::{Deserialize, Serialize};
use tracing::{debug, info};

#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum PrinterVendor {
    Bambu,
    Prusa,
    Klipper,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DiscoveredPrinter {
    pub vendor: PrinterVendor,
    pub host: String,
    pub serial: Option<String>,
}

/// Periodically sweeps the LAN for printers (SSDP for Bambu, mDNS for
/// PrusaLink/Moonraker) and reports newly-seen devices upstream.
///
/// This is intentionally a stub: production discovery would bind a UDP
/// multicast socket per protocol. It's structured so each protocol's probe
/// can be dropped in independently without touching the polling loop.
pub async fn run(interval: Duration, tx: tokio::sync::mpsc::Sender<DiscoveredPrinter>) {
    let mut ticker = tokio::time::interval(interval);
    loop {
        ticker.tick().await;
        debug!("running LAN discovery sweep");

        for printer in sweep().await {
            info!(host = %printer.host, ?printer.vendor, "discovered printer");
            if tx.send(printer).await.is_err() {
                return;
            }
        }
    }
}

async fn sweep() -> Vec<DiscoveredPrinter> {
    // TODO: SSDP probe (Bambu), mDNS `_prusalink._tcp` / `_moonraker._tcp` probes.
    Vec::new()
}