//! `gatewayd` end to end: each turn's speaker is the Mattermost username of the one person who
//! wrote every message of its burst, and there is none when two people did or the name cannot be
//! found (M5c spec, sections 4 and 11). Do not edit.

#[path = "support/fake_loop.rs"]
mod fake_loop;
#[path = "support/fake_mm.rs"]
mod fake_mm;
#[path = "support/gateway.rs"]
mod gateway;
#[path = "support/tmp.rs"]
mod tmp;

use std::sync::{Mutex, mpsc};
use std::time::{Duration, Instant};

use fake_loop::{done, serve_loop};
use fake_mm::{DM, EVE, FakeMm, KYLE, id, post};
use gateway::{SHARED, WAIT, loop_dir, read_state, start, up};
use gatewayd::config::Config;
use tmp::TempDir;

/// Kyle and Eve both allowed, in the shared channel.
fn two_people(home: &TempDir, url: &str) -> Config {
    let text = format!(
        r#"
[mattermost]
url = "{url}"
[secrets.mattermost_token]
env = "NOT_READ_BY_RUN"
[allow]
users = ["{KYLE}", "{EVE}"]
channels = ["{SHARED}"]
[paths]
home = "{}"
[limits]
typing_every_ms = 100
"#,
        home.path().display()
    );
    Config::parse(&text).unwrap()
}

/// Wait until `gatewayd` has handled `post`: its id is in the state file's `recent`. The post is
/// queued by then, since the event loop finishes a post before it looks at ended turns.
fn wait_handled(home: &TempDir, post: &str) {
    let until = Instant::now() + WAIT;
    loop {
        let state = read_state(home);
        if state["recent"]
            .as_array()
            .is_some_and(|r| r.iter().any(|p| p == post))
        {
            return;
        }
        assert!(Instant::now() < until, "{post} not handled: {state}");
        std::thread::sleep(Duration::from_millis(10));
    }
}

fn lookups(mm: &FakeMm, user: &str) -> usize {
    let path = format!("/api/v4/users/{user}");
    mm.calls()
        .iter()
        .filter(|(m, p)| m == "GET" && *p == path)
        .count()
}

#[test]
fn one_persons_message_has_their_username() {
    let home = TempDir::new("speaker-one");
    let (mm, _running, turns, mut ws) = up(&home, Duration::ZERO);
    ws.posted(&post(&id('p', 1), KYLE, DM, "", "hello there", 5), "D");
    let turn = turns.recv_timeout(WAIT).unwrap();
    assert_eq!(
        (turn.content.as_str(), turn.speaker.as_deref()),
        ("hello there", Some("kyle"))
    );
    assert_eq!(mm.wait_posts(1, WAIT).len(), 1);
}

#[test]
fn a_username_is_looked_up_once() {
    let home = TempDir::new("speaker-cache");
    let (mm, _running, turns, mut ws) = up(&home, Duration::ZERO);
    ws.posted(&post(&id('p', 1), KYLE, DM, "", "first", 5), "D");
    ws.posted(&post(&id('p', 2), KYLE, DM, "", "second", 6), "D");
    let speakers = [
        turns.recv_timeout(WAIT).unwrap().speaker,
        turns.recv_timeout(WAIT).unwrap().speaker,
    ];
    assert_eq!(
        speakers,
        [Some("kyle".to_string()), Some("kyle".to_string())]
    );
    assert_eq!(lookups(&mm, KYLE), 1, "{:?}", mm.calls());
}

#[test]
fn bursts_have_a_speaker_only_when_one_person_wrote_them() {
    let home = TempDir::new("speaker-burst");
    loop_dir(&home);
    let (release_tx, release_rx) = mpsc::channel::<()>();
    let release = Mutex::new(release_rx);
    let turns = serve_loop(&home.path().join("run/loop/loop.sock"), move |n, turn| {
        if n <= 1 {
            let _ = release.lock().unwrap().recv_timeout(WAIT);
        }
        vec![done(&format!("answer to {}", turn.content))]
    });
    let mm = FakeMm::start();
    let _running = start(two_people(&home, &mm.url()));
    let mut ws = mm.next_ws(WAIT);
    let p1 = id('p', 1);
    ws.posted(
        &post(&p1, KYLE, SHARED, "", "@boxmaker-straylight start", 5),
        "O",
    );
    let first = turns.recv_timeout(WAIT).unwrap();
    assert_eq!(
        (first.content.as_str(), first.speaker.as_deref()),
        ("start", Some("kyle"))
    );

    // Eve and Kyle while the first turn runs: one turn, from two people.
    ws.posted(&post(&id('p', 2), EVE, SHARED, &p1, "two", 6), "O");
    ws.posted(&post(&id('p', 3), KYLE, SHARED, &p1, "three", 7), "O");
    wait_handled(&home, &id('p', 3));
    release_tx.send(()).unwrap();
    let second = turns.recv_timeout(WAIT).unwrap();
    assert_eq!(
        (second.content.as_str(), second.resume),
        ("two\n\nthree", true),
        "the text is joined as before"
    );
    assert_eq!(second.speaker, None, "two people: no speaker");

    // Eve alone while the second runs: her name, and nothing left over from the burst before.
    ws.posted(&post(&id('p', 4), EVE, SHARED, &p1, "four", 8), "O");
    wait_handled(&home, &id('p', 4));
    release_tx.send(()).unwrap();
    let third = turns.recv_timeout(WAIT).unwrap();
    assert_eq!(
        (third.content.as_str(), third.speaker.as_deref()),
        ("four", Some("user-e000"))
    );
    assert_eq!(mm.wait_posts(3, WAIT).len(), 3);
}

#[test]
fn a_name_that_cannot_be_found_leaves_the_turn_without_a_speaker() {
    let home = TempDir::new("speaker-missing");
    let (mm, running, turns, mut ws) = up(&home, Duration::ZERO);
    mm.refuse_users(true);
    ws.posted(&post(&id('p', 1), KYLE, DM, "", "hello", 5), "D");
    let turn = turns.recv_timeout(WAIT).unwrap();
    assert_eq!(
        (turn.content.as_str(), turn.speaker),
        ("hello", None),
        "never the user id, never a guess"
    );
    assert_eq!(
        mm.wait_posts(1, WAIT).len(),
        1,
        "the turn is answered all the same"
    );
    let line = format!(
        "gatewayd: no username for {KYLE}: status 404: \"{{\\\"message\\\":\\\"not found\\\"}}\"; \
         the turn has no speaker"
    );
    let log = running.wait_log("no username for");
    assert_eq!(
        log.iter()
            .filter(|l| l.contains("no username"))
            .collect::<Vec<_>>(),
        [&line]
    );

    // A failure is not remembered: the next turn looks again.
    mm.refuse_users(false);
    ws.posted(&post(&id('p', 2), KYLE, DM, "", "again", 6), "D");
    let again = turns.recv_timeout(WAIT).unwrap();
    assert_eq!(
        (again.content.as_str(), again.speaker.as_deref()),
        ("again", Some("kyle"))
    );
    assert_eq!(lookups(&mm, KYLE), 2, "{:?}", mm.calls());
}