ch32rv 0.9.0

//! en: `arduino discovery` / `arduino monitor` (docs/cli.ja.md §4.11): the Arduino Pluggable
//! Discovery and Monitor protocols (line-based stdio JSON). Discovery exposes each WCH probe as a
//! `wchlink://<serial>` port; Monitor wraps the DMI sources (dmdata / rtt) as the IDE's Serial
//! Monitor, both ways (what the user types reaches the sketch). uart / sdi need no wrapper: the
//! IDE opens the probe's CDC port with its builtin serial monitor. Machine-facing: never mixes
//! human text onto stdout.
//! ja: `arduino discovery`/`monitor`。Arduino の Pluggable Discovery/Monitor プロトコル(行単位の
//! stdio JSON)。discovery は各 WCH probe を `wchlink://<serial>` port として公開、monitor は DMI
//! source(dmdata / rtt)を IDE の Serial Monitor として双方向に wrap する。uart / sdi は IDE の
//! builtin serial monitor が CDC を直接開くので wrap 不要。

use std::io::{BufRead, Write};
use std::process::ExitCode;

use serde_json::{Value, json};

use crate::args::Cli;

/// `arduino discovery`: the Pluggable Discovery protocol over stdio.
pub fn discovery(_cli: &Cli) -> ExitCode {
    let stdin = std::io::stdin();
    let mut out = std::io::stdout();
    for line in stdin.lock().lines() {
        let Ok(line) = line else { break };
        let word = line
            .split_whitespace()
            .next()
            .unwrap_or("")
            .to_ascii_uppercase();
        match word.as_str() {
            "" => {}
            "HELLO" => emit(
                &mut out,
                &json!({"eventType":"hello","protocolVersion":1,"message":"OK"}),
            ),
            "START" => emit(&mut out, &json!({"eventType":"start","message":"OK"})),
            "STOP" => emit(&mut out, &json!({"eventType":"stop","message":"OK"})),
            "LIST" => emit(&mut out, &json!({"eventType":"list","ports": list_ports()})),
            "START_SYNC" => {
                // We do not watch USB hotplug yet: acknowledge, emit the current ports once as
                // `add` events, then rely on the IDE's periodic re-LIST for changes.
                emit(&mut out, &json!({"eventType":"start_sync","message":"OK"}));
                for p in list_ports() {
                    emit(&mut out, &json!({"eventType":"add","port": p}));
                }
            }
            "QUIT" => {
                emit(&mut out, &json!({"eventType":"quit","message":"OK"}));
                return ExitCode::SUCCESS;
            }
            other => emit(
                &mut out,
                &json!({"eventType": other.to_ascii_lowercase(), "error": true, "message": format!("unknown command {other}")}),
            ),
        }
    }
    ExitCode::SUCCESS
}

/// Enumerate WCH probes as Pluggable-Discovery ports (from USB descriptors only - no AttachChip,
/// so it never disturbs an in-flight upload/monitor on the same probe).
fn list_ports() -> Vec<Value> {
    let entries = crate::cmd_probe::wch_devices().unwrap_or_default();
    entries
        .iter()
        .map(|e| {
            let serial = e.dev.serial().unwrap_or("unknown");
            json!({
                "address": format!("wchlink://{serial}"),
                "label": format!("WCH-Link {serial}"),
                "protocol": "wchlink",
                "protocolLabel": "WCH-Link (RISC-V debug)",
                "hardwareId": serial,
                "properties": {
                    "serial": serial,
                    "vid": format!("0x{:04x}", e.dev.vid()),
                    "pid": format!("0x{:04x}", e.dev.pid()),
                    "mode": crate::cmd_probe::mode_str(e.mode),
                },
            })
        })
        .collect()
}

fn emit(out: &mut impl Write, v: &Value) {
    // One compact JSON object per line; flush so the IDE sees it immediately.
    let _ = writeln!(out, "{v}");
    let _ = out.flush();
}

// ---- arduino monitor (Pluggable Monitor protocol) ----

use std::net::{Shutdown, TcpStream};
use std::sync::Arc;
use std::sync::atomic::{AtomicBool, Ordering};
use std::thread::JoinHandle;
use std::time::Duration;

use ch32rv_contract::policy::MonitorSource;

use crate::source::{self, DmiSource};

/// The sources this monitor wraps (the DMI ones; uart/sdi are the IDE's own serial monitor).
const SOURCES: [MonitorSource; 2] = [MonitorSource::Dmdata, MonitorSource::Rtt];

/// `arduino monitor`: the Pluggable Monitor protocol over stdio. OPEN connects (TCP client) to the
/// IDE-provided address and pipes the target's runtime output to it and the IDE's input back.
/// `source` (dmdata, the default, or rtt) selects the backend.
pub fn monitor(_cli: &Cli) -> ExitCode {
    let stdin = std::io::stdin();
    let mut out = std::io::stdout();
    let mut source = MonitorSource::Dmdata;
    let stop = Arc::new(AtomicBool::new(false));
    let mut stream: Option<(JoinHandle<()>, TcpStream)> = None;

    // CLOSE / QUIT: stop the pipe thread and shut the socket so its blocked reads/writes end.
    let close = |stream: &mut Option<(JoinHandle<()>, TcpStream)>| {
        stop.store(true, Ordering::SeqCst);
        if let Some((h, sock)) = stream.take() {
            let _ = sock.shutdown(Shutdown::Both);
            let _ = h.join();
        }
    };

    for line in stdin.lock().lines() {
        let Ok(line) = line else { break };
        let parts: Vec<&str> = line.split_whitespace().collect();
        let word = parts.first().copied().unwrap_or("").to_ascii_uppercase();
        match word.as_str() {
            "" => {}
            "HELLO" => emit(
                &mut out,
                &json!({"eventType":"hello","protocolVersion":1,"message":"OK"}),
            ),
            "DESCRIBE" => emit(
                &mut out,
                &json!({
                    "eventType":"describe","message":"OK",
                    "port_descriptor": {
                        "protocol":"wchlink",
                        "configuration_parameters": {
                            "source": {
                                "label":"Runtime output source","type":"enum",
                                "values": SOURCES.iter().map(|s| s.as_str()).collect::<Vec<_>>(),
                                "selected": source.as_str()
                            }
                        }
                    }
                }),
            ),
            "CONFIGURE" => {
                let picked = (parts.len() >= 3 && parts[1] == "source")
                    .then(|| SOURCES.iter().find(|s| s.as_str() == parts[2]))
                    .flatten();
                match picked {
                    Some(s) => {
                        source = *s;
                        emit(&mut out, &json!({"eventType":"configure","message":"OK"}));
                    }
                    None => emit(
                        &mut out,
                        &json!({"eventType":"configure","error":true,
                        "message":"CONFIGURE source <dmdata|rtt>"}),
                    ),
                }
            }
            "OPEN" => {
                // OPEN <client-host:port> <port-address>
                let (Some(&client), Some(&port)) = (parts.get(1), parts.get(2)) else {
                    emit(
                        &mut out,
                        &json!({"eventType":"open","error":true,"message":"OPEN needs <host:port> <port>"}),
                    );
                    continue;
                };
                let serial = port.strip_prefix("wchlink://").unwrap_or(port).to_string();
                match TcpStream::connect(client).and_then(|s| Ok((s.try_clone()?, s))) {
                    Ok((keep, sock)) => {
                        stop.store(false, Ordering::SeqCst);
                        let stop2 = stop.clone();
                        let handle = std::thread::spawn(move || pipe(&serial, source, sock, stop2));
                        stream = Some((handle, keep));
                        emit(&mut out, &json!({"eventType":"open","message":"OK"}));
                    }
                    Err(e) => emit(
                        &mut out,
                        &json!({"eventType":"open","error":true,
                        "message":format!("connect {client}: {e}")}),
                    ),
                }
            }
            "CLOSE" => {
                close(&mut stream);
                emit(&mut out, &json!({"eventType":"close","message":"OK"}));
            }
            "QUIT" => {
                close(&mut stream);
                emit(&mut out, &json!({"eventType":"quit","message":"OK"}));
                return ExitCode::SUCCESS;
            }
            other => emit(
                &mut out,
                &json!({
                "eventType": other.to_ascii_lowercase(),"error":true,
                "message":format!("unknown command {other}")}),
            ),
        }
    }
    close(&mut stream);
    ExitCode::SUCCESS
}

/// Attach to the probe with `serial`, open `source`, resume the core, and exchange the target's
/// output / the IDE's input with `sock` until `stop` is set or the socket goes away.
fn pipe(serial: &str, source: MonitorSource, mut sock: TcpStream, stop: Arc<AtomicBool>) {
    let Ok(entries) = crate::cmd_probe::wch_devices() else {
        return;
    };
    let Some(entry) = entries.into_iter().find(|e| e.dev.serial() == Some(serial)) else {
        return;
    };
    let mut warnings = Vec::new();
    let mut session = match crate::session::Session::attach(
        &entry,
        ch32rv_wchlink::Speed::High,
        Duration::from_millis(1000),
        Duration::from_secs(10),
        None,
        None,
        &mut warnings,
    ) {
        Ok(s) => s,
        Err(_) => return,
    };
    let Ok(mut src) = DmiSource::open(&mut session, source, &mut warnings) else {
        return;
    };
    let _ = session.dm().resume(); // the sources only move while the core runs
    let Ok(reader) = sock.try_clone() else {
        return;
    };
    let input = source::spawn_reader(reader);
    let mut pending = Vec::new();
    while !stop.load(Ordering::SeqCst) {
        source::drain_input(&input, &mut pending);
        match src.poll(&mut session, &mut pending) {
            Ok(bytes) if !bytes.is_empty() => {
                if sock.write_all(&bytes).is_err() {
                    break;
                }
                let _ = sock.flush();
            }
            Ok(_) => std::thread::sleep(src.idle()),
            Err(_) => break,
        }
    }
}