use notify::{Config, RecommendedWatcher, RecursiveMode, Watcher};

/// Async, futures channel based event watching
fn main() {
    let mut args = std::env::args();
    let _ = args.next();
    let path_1 = args.next()
        .expect("Argument 1 needs to be a path");
    let path_2 = args.next();

    let (tx, rx) = std::sync::mpsc::channel();

    // Automatically select the best implementation for your platform.
    // You can also access each implementation directly e.g. INotifyWatcher.
    let mut main_watcher = RecommendedWatcher::new(
        move |res| {
            tx.send(res).expect("channel closed");
        },
        Config::default(),
    ).expect("Failed to create watcher");
    // Add a path to be watched. All files and directories at that path and
    // below will be monitored for changes.
    println!("watching {path_1} recursively");
    main_watcher.watch(path_1.as_ref(), RecursiveMode::Recursive).expect("Failed to watch first path");
    if let Some(path_2) = path_2 {
        println!("watching {path_2} recursively");
        main_watcher.watch(path_2.as_ref(), RecursiveMode::Recursive).expect("Failed to watch second path");
    }

    while let Ok(res) = rx.recv() {
        match res {
            Ok(event) => println!("{:?}: {:?}", event.kind, event.paths),
            Err(e) => println!("watch error: {:?}", e),
        }
    }
}