//! `view` and `comments` against a mock forge whose issue-comments
//! endpoint behaves like Forgejo's: it takes no page or limit and returns
//! the whole thread on every request. Drives the compiled binary, since
//! the request code is inline in each verb's `run()`.

use std::io::{BufRead as _, BufReader, Write as _};
use std::net::{TcpListener, TcpStream};
use std::path::PathBuf;
use std::process::Command;

/// More than one 50-row page, so a loop that pages until a short page
/// never sees one.
const THREAD_LEN: usize = 60;

/// The issue the mock forge serves; any other route gets an empty list.
const NUMBER: &str = "1";

/// A unique scratch `HYPERHIVE_STATE_DIR` holding a `forge-token` file,
/// same manual-tmpdir pattern as `credential_helper.rs`.
fn scratch_state_dir(tag: &str) -> PathBuf {
    let ts = std::time::SystemTime::now()
        .duration_since(std::time::UNIX_EPOCH)
        .map_or(0, |d| d.as_nanos());
    let dir = std::env::temp_dir().join(format!("hive-forge-comments-test-{tag}-{ts}"));
    std::fs::create_dir_all(&dir).expect("create scratch state dir");
    std::fs::write(dir.join("forge-token"), "test-token\n").expect("seed forge-token");
    dir
}

/// Answer one request. The comments route ignores the query string, as
/// the real endpoint does; any route the verbs only read best-effort
/// (notifications, reactions, PR reviews) gets an empty list.
fn serve(mut stream: TcpStream) {
    let mut reader = BufReader::new(stream.try_clone().expect("clone stream"));
    let mut request_line = String::new();
    reader
        .read_line(&mut request_line)
        .expect("read request line");
    loop {
        let mut line = String::new();
        if reader.read_line(&mut line).expect("read header") == 0 || line == "\r\n" {
            break;
        }
    }
    let target = request_line.split_whitespace().nth(1).unwrap_or("");
    let path = target.split('?').next().unwrap_or("");
    let issue = format!("/api/v1/repos/o/r/issues/{NUMBER}");
    let body = match path {
        p if p == format!("{issue}/comments") => serde_json::Value::Array(
            (0..THREAD_LEN)
                .map(|i| {
                    serde_json::json!({
                        "id": i + 1,
                        "body": format!("comment {i}"),
                        "user": {"login": "someone"},
                        "created_at": format!("2026-10-09T00:{:02}:00Z", i % 60),
                    })
                })
                .collect(),
        ),
        p if p == issue => serde_json::json!({
            "number": NUMBER.parse::<u64>().expect("numeric NUMBER"),
            "title": "a long thread",
            "body": "",
            "state": "open",
            "user": {"login": "someone"},
        }),
        _ => serde_json::json!([]),
    }
    .to_string();
    let response = format!(
        "HTTP/1.1 200 OK\r\nContent-Type: application/json\r\nX-Total-Count: {THREAD_LEN}\r\nContent-Length: {}\r\nConnection: close\r\n\r\n{body}",
        body.len()
    );
    stream
        .write_all(response.as_bytes())
        .expect("write response");
}

/// Start the mock forge on a loopback port; returns its base URL.
fn mock_forge() -> String {
    let listener = TcpListener::bind("127.0.0.1:0").expect("bind mock forge");
    let addr = listener.local_addr().expect("mock forge addr");
    std::thread::spawn(move || {
        for stream in listener.incoming() {
            serve(stream.expect("accept"));
        }
    });
    format!("http://{addr}")
}

/// Run `hive-forge -r o/r <args>` against a fresh mock forge; returns
/// stdout, asserting the run succeeded.
fn hive_forge(tag: &str, args: &[&str]) -> String {
    let out = Command::new(env!("CARGO_BIN_EXE_hive-forge"))
        .args(["-r", "o/r"])
        .args(args)
        .env("HIVE_FORGE_URL", mock_forge())
        .env("HYPERHIVE_STATE_DIR", scratch_state_dir(tag))
        .env_remove("HIVE_FORGE_TOKEN_FILE")
        .env_remove("HIVE_LABEL")
        .output()
        .expect("run hive-forge");
    let stdout = String::from_utf8_lossy(&out.stdout).into_owned();
    assert!(
        out.status.success(),
        "hive-forge {args:?} failed\nstdout:\n{stdout}\nstderr:\n{}",
        String::from_utf8_lossy(&out.stderr)
    );
    stdout
}

/// Rendered comments: both verbs start each one with a bold `**` author.
fn comment_count(stdout: &str) -> usize {
    stdout.lines().filter(|l| l.starts_with("**")).count()
}

#[test]
fn view_prints_each_comment_once() {
    let stdout = hive_forge("view", &["view", NUMBER]);
    assert_eq!(comment_count(&stdout), THREAD_LEN, "{stdout}");
    assert!(stdout.contains(&format!("## Comments ({THREAD_LEN})")));
}

#[test]
fn comments_limit_returns_exactly_limit() {
    let stdout = hive_forge("limit", &["comments", NUMBER, "--limit", "5"]);
    assert_eq!(comment_count(&stdout), 5, "{stdout}");
    assert!(stdout.contains(&format!("({} more comment(s)", THREAD_LEN - 5)));
}

#[test]
fn comments_tail_returns_the_last_n() {
    let stdout = hive_forge("tail", &["comments", NUMBER, "--tail", "3"]);
    assert_eq!(comment_count(&stdout), 3, "{stdout}");
    assert!(stdout.contains(&format!("comment {}", THREAD_LEN - 1)));
    assert!(!stdout.contains(&format!("comment {}", THREAD_LEN - 4)));
    assert!(stdout.contains(&format!("({} earlier comment(s)", THREAD_LEN - 3)));
}

#[test]
fn comments_since_limit_above_a_page_returns_exactly_limit() {
    let stdout = hive_forge(
        "since-limit",
        &[
            "--json",
            "comments",
            NUMBER,
            "--since",
            "2026-10-09T00:00:00Z",
            "--limit",
            "55",
        ],
    );
    let out: serde_json::Value = serde_json::from_str(&stdout).expect("comments --json output");
    assert_eq!(out["comments"].as_array().map(Vec::len), Some(55));
    assert_eq!(out["since_more"], true);
    assert_eq!(out["since_limit_clamped"], false);
}