//! `wai serve <role>` against the programs it starts: the room service and the relay.
//!
//! - `wai serve room --config <file> --check` prints what `wai-room --config <file> --check` prints
//!   and exits as it exits, byte for byte: the configuration and the keys it names read as the
//!   service starts from them, and refused (exit 1) when either does not read; nothing is started;
//! - the same for the relay, its example configuration and one it refuses;
//! - `wai serve room --config <file>` starts the room service itself, which answers on the address
//!   its configuration names.
//!
//! `wai` is built from `wai/wai-rs` with the feature `mcp` into the target directory
//! tests/cli_dev_room.rs builds it in, and the relay `wai-relay` from the joule-code workspace.

use std::path::{Path, PathBuf};
use std::process::{Command, Output, Stdio};
use std::time::{Duration, Instant};

fn cargo() -> String {
    std::env::var("CARGO").ok().or(option_env!("CARGO").map(String::from)).unwrap_or_else(|| "cargo".into())
}

fn exe(name: &str) -> String {
    if cfg!(windows) { format!("{name}.exe") } else { name.to_string() }
}

fn wai_bin() -> PathBuf {
    let manifest = Path::new(env!("CARGO_MANIFEST_DIR")).join("../../../../wai/wai-rs/Cargo.toml");
    let target = Path::new(env!("CARGO_TARGET_TMPDIR")).join("wai-mcp");
    let status = Command::new(cargo())
        .args(["build", "--locked", "--no-default-features", "--features", "mcp", "--bin", "wai", "--manifest-path"])
        .arg(&manifest)
        .env("CARGO_TARGET_DIR", &target)
        .status()
        .expect("cargo runs");
    assert!(status.success(), "the wai binary builds with the feature mcp");
    target.join("debug").join(exe("wai"))
}

fn relay_bin() -> PathBuf {
    let manifest = Path::new(env!("CARGO_MANIFEST_DIR")).join("../../Cargo.toml");
    let target = Path::new(env!("CARGO_TARGET_TMPDIR")).join("wai-relay");
    let status = Command::new(cargo())
        .args(["build", "--locked", "-p", "joule-moq-relay", "--bin", "wai-relay", "--manifest-path"])
        .arg(&manifest)
        .env("CARGO_TARGET_DIR", &target)
        .status()
        .expect("cargo runs");
    assert!(status.success(), "the relay builds");
    target.join("debug").join(exe("wai-relay"))
}

fn run(bin: &Path, dir: &Path, args: &[&str]) -> Output {
    Command::new(bin).current_dir(dir).args(args).env("WAI_CONFIG_DIR", dir.join(".wai-config")).stdin(Stdio::null()).output().expect("it runs")
}

fn text(o: &Output) -> String {
    format!("{}{}", String::from_utf8_lossy(&o.stdout), String::from_utf8_lossy(&o.stderr))
}

fn same(a: &Output, b: &Output, what: &str) {
    assert_eq!(a.status.code(), b.status.code(), "{what}: the exit status\n{}\n---\n{}", text(a), text(b));
    assert_eq!(String::from_utf8_lossy(&a.stdout), String::from_utf8_lossy(&b.stdout), "{what}: standard output");
    assert_eq!(String::from_utf8_lossy(&a.stderr), String::from_utf8_lossy(&b.stderr), "{what}: standard error");
}

fn example(rel: &str) -> String {
    std::fs::read_to_string(Path::new(env!("CARGO_MANIFEST_DIR")).join(rel)).unwrap()
}

/// A port no one listens on now.
fn free_port() -> u16 {
    std::net::TcpListener::bind("127.0.0.1:0").unwrap().local_addr().unwrap().port()
}

#[test]
fn serve_checks_and_starts_each_program_as_itself() {
    let wai = wai_bin();
    let relay = relay_bin();
    let room = Path::new(env!("CARGO_BIN_EXE_wai-room"));
    let d = std::env::temp_dir().join(format!("joule-moq-room-serve-{}", std::process::id()));
    let _ = std::fs::remove_dir_all(&d);
    std::fs::create_dir_all(&d).unwrap();
    let keygen = run(room, &d, &["keygen", "keys.toml"]);
    assert!(keygen.status.success(), "{}", text(&keygen));
    let port = free_port();
    let cfg = example("room.example.toml").replace("keys = \"/path/to/keys.toml\"", "keys = \"keys.toml\"").replace("listen = \"127.0.0.1:9682\"", &format!("listen = \"127.0.0.1:{port}\""));
    assert!(cfg.contains("keys = \"keys.toml\"") && cfg.contains(&port.to_string()), "room.example.toml names its keys and listen address as this test reads them");
    std::fs::write(d.join("room.toml"), &cfg).unwrap();
    std::fs::write(d.join("no-keys.toml"), cfg.replace("keys = \"keys.toml\"", "keys = \"gone.toml\"")).unwrap();
    std::fs::write(d.join("not-toml.toml"), "listen = \n").unwrap();
    let r = room.to_str().unwrap();
    for (file, holds) in [("room.toml", true), ("no-keys.toml", false), ("not-toml.toml", false)] {
        let ours = run(&wai, &d, &["serve", "room", "--config", file, "--check", "--bin", r]);
        let theirs = run(room, &d, &["--config", file, "--check"]);
        same(&ours, &theirs, file);
        assert_eq!(theirs.status.success(), holds, "{file}: {}", text(&theirs));
    }
    // The relay: its example, and the example with an address that is none.
    let rl = relay.to_str().unwrap();
    std::fs::write(d.join("relay.toml"), example("../joule-moq-relay/relay.example.toml")).unwrap();
    std::fs::write(d.join("bad-relay.toml"), example("../joule-moq-relay/relay.example.toml").replacen("quic_listen = \"127.0.0.1:4443\"", "quic_listen = \"nowhere\"", 1)).unwrap();
    for (file, holds) in [("relay.toml", true), ("bad-relay.toml", false)] {
        let ours = run(&wai, &d, &["serve", "relay", "--config", file, "--check", "--bin", rl]);
        let theirs = run(&relay, &d, &["--config", file, "--check"]);
        same(&ours, &theirs, file);
        assert_eq!(theirs.status.success(), holds, "{file}: {}", text(&theirs));
    }
    // Started: the room service answers where its configuration says, as the program itself.
    let mut child = Command::new(&wai)
        .current_dir(&d)
        .args(["serve", "room", "--config", "room.toml", "--bin", r])
        .stdin(Stdio::null())
        .stdout(Stdio::null())
        .stderr(Stdio::null())
        .spawn()
        .expect("wai serve starts");
    let until = Instant::now() + Duration::from_secs(20);
    let mut up = false;
    while Instant::now() < until {
        if std::net::TcpStream::connect(("127.0.0.1", port)).is_ok() {
            up = true;
            break;
        }
        if let Ok(Some(s)) = child.try_wait() {
            panic!("wai serve room stopped: {s}");
        }
        std::thread::sleep(Duration::from_millis(100));
    }
    let _ = child.kill();
    let _ = child.wait();
    assert!(up, "the room service listens on 127.0.0.1:{port}");
    let _ = std::fs::remove_dir_all(&d);
}