use log::{debug, error};
use mdns_sd::{ServiceDaemon, ServiceEvent};

use crate::local_presence::SERVICE_NAME;

pub type DiscoveryEvent = ServiceEvent;

pub async fn discover_agents<F>(timeout: Option<u64>, on_event: F)
where
    F: FnOnce(DiscoveryEvent) -> Result<(), String> + Send + 'static + Copy,
{
    // Create a new mDNS daemon.
    let mdns = ServiceDaemon::new().expect("Failed to create mDNS daemon");

    // Start browsing for the service type.
    // The receiver will be a stream of events.
    let receiver = mdns.browse(SERVICE_NAME).expect("Failed to browse");

    tokio::spawn(async move {
        while let Ok(event) = receiver.recv() {
            if let Err(e) = on_event(event.clone()) {
                error!("Event callback failed : {e}");
            }
            match event {
                ServiceEvent::ServiceResolved(resolved) => {
                    debug!("Resolved a new service: {}", resolved.fullname);
                }
                other_event => {
                    debug!("Received other event: {:?}", &other_event);
                }
            }
        }
    });

    if let Some(timeout) = timeout {
        tokio::time::sleep(std::time::Duration::from_secs(timeout)).await;
        mdns.shutdown().unwrap();
    }
}