use std::{fs, path::PathBuf, thread, time::Duration};

use api::PlacementStore;

fn tmp_file(name: &str) -> PathBuf {
    let mut p = std::env::temp_dir();
    p.push(format!(
        "cloudlysis-control-{name}-{}-{}.json",
        std::process::id(),
        std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)
            .unwrap()
            .as_nanos()
    ));
    p
}

#[test]
fn placement_store_hot_reload_swaps_atomically() {
    let path = tmp_file("placement");
    fs::write(
        &path,
        r#"{"revision":"r1","aggregate_placement":{"placements":[]},"projection_placement":{"placements":[]},"runner_placement":{"placements":[]}}"#,
    )
    .unwrap();

    let store = PlacementStore::new(path.clone());
    let a1 = store.get_for_kind(api::ServiceKind::Aggregate);
    assert_eq!(a1.revision, "r1");

    thread::sleep(Duration::from_millis(5));

    fs::write(
        &path,
        r#"{"revision":"r2","aggregate_placement":{"placements":[]},"projection_placement":{"placements":[]},"runner_placement":{"placements":[]}}"#,
    )
    .unwrap();

    let a2 = store.get_for_kind(api::ServiceKind::Aggregate);
    assert_eq!(a2.revision, "r2");

    let _ = fs::remove_file(&path);
}