node-app-build 0.1.0

//! Split-pane TUI for `node-app dev`.
//!
//! # Channel architecture
//!
//! ```text
//! ┌─ producers ──────────────────────────────────────────────────┐
//! │  orchestrator  ──────────────────────────────────────┐       │
//! │  daemon reader threads  ─────────────────────────────┤       │
//! │  ui-server reader threads  ──────────────────────────┤       │
//! │  build capture threads  ─────────────────────────────┤       │
//! └──────────────────────────────────────────────────────▼───────┘
//!                                                SyncSender<TuiEvent>
//!                                                        │
//!                                               TUI render thread
//!                                            (drains rx, draws frame)
//! ```
//!
//! Back-pressure (keyboard → orchestrator) uses `Arc<AtomicBool>` flags so
//! the orchestrator can poll cheaply inside the debounce loop.

pub mod render;
pub mod state;

use std::io;
use std::sync::atomic::{AtomicBool, Ordering};
use std::sync::{mpsc, Arc};
use std::time::{Duration, Instant};

use crossterm::{
    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode, KeyModifiers},
    execute,
    terminal::{self, EnterAlternateScreen, LeaveAlternateScreen},
};
use ratatui::{backend::CrosstermBackend, Terminal};

pub use state::{LogSource, ServiceStatus};

const TICK: Duration = Duration::from_millis(30);

// ── Public types ─────────────────────────────────────────────────────────────

#[derive(Debug)]
pub struct LogEntry {
    pub source: LogSource,
    pub line: String,
}

/// All events flowing from producers into the TUI render thread.
#[derive(Debug)]
pub enum TuiEvent {
    Log(LogEntry),
    Status {
        source: LogSource,
        status: ServiceStatus,
        detail: Option<String>,
    },
}

pub type LogTx = mpsc::SyncSender<TuiEvent>;
pub type LogRx = mpsc::Receiver<TuiEvent>;

/// Signals written by the TUI keyboard handler and read by the orchestrator,
/// plus one signal written by the orchestrator and read by the TUI.
#[derive(Clone)]
pub struct DevSignals {
    pub restart_requested: Arc<AtomicBool>,
    pub build_now_requested: Arc<AtomicBool>,
    /// Set by TUI on q / Ctrl+C — tells orchestrator to start shutting down.
    pub quit_requested: Arc<AtomicBool>,
    /// Set by orchestrator once host_impl.shutdown() fully completes — tells
    /// the TUI it is safe to restore the terminal and exit.
    pub shutdown_complete: Arc<AtomicBool>,
}

impl DevSignals {
    fn new() -> Self {
        Self {
            restart_requested: Arc::new(AtomicBool::new(false)),
            build_now_requested: Arc::new(AtomicBool::new(false)),
            quit_requested: Arc::new(AtomicBool::new(false)),
            shutdown_complete: Arc::new(AtomicBool::new(false)),
        }
    }

    /// Returns true and clears the flag if a restart was requested.
    pub fn take_restart(&self) -> bool {
        self.restart_requested.swap(false, Ordering::SeqCst)
    }

    /// Returns true and clears the flag if an immediate build was requested.
    pub fn take_build_now(&self) -> bool {
        self.build_now_requested.swap(false, Ordering::SeqCst)
    }

    pub fn should_quit(&self) -> bool {
        self.quit_requested.load(Ordering::SeqCst)
    }

    /// Called by the orchestrator after shutdown is complete.
    pub fn mark_shutdown_complete(&self) {
        self.shutdown_complete.store(true, Ordering::SeqCst);
    }
}

// ── Setup ────────────────────────────────────────────────────────────────────

/// Create channels + signals. Returns `(producer tx, consumer rx, signals)`.
pub fn setup() -> (LogTx, LogRx, DevSignals) {
    let (tx, rx) = mpsc::sync_channel(512);
    (tx, rx, DevSignals::new())
}

/// Returns true when stdout is a real TTY (i.e. TUI should be enabled).
pub fn is_tty() -> bool {
    use std::io::IsTerminal;
    std::io::stdout().is_terminal()
}

// ── Helpers for producers ────────────────────────────────────────────────────

/// Send a System-level log line, or fall back to `eprintln!` when no sink.
pub fn sys_log(tx: Option<&LogTx>, line: impl Into<String>) {
    match tx {
        Some(t) => {
            let _ = t.send(TuiEvent::Log(LogEntry {
                source: LogSource::System,
                line: line.into(),
            }));
        }
        None => eprintln!("{}", line.into()),
    }
}

/// Send a service-status update.
pub fn update_status(
    tx: Option<&LogTx>,
    source: LogSource,
    status: ServiceStatus,
    detail: Option<String>,
) {
    if let Some(t) = tx {
        let _ = t.send(TuiEvent::Status {
            source,
            status,
            detail,
        });
    }
}

// ── TUI render loop ──────────────────────────────────────────────────────────

/// Run the TUI. Blocks until the user presses `q` / `Ctrl+C`.
/// Call from a dedicated thread; the main thread continues running the
/// orchestrator while this thread owns the terminal.
pub fn run(rx: LogRx, mut app: state::AppState, signals: DevSignals) -> io::Result<()> {
    terminal::enable_raw_mode()?;
    let mut stdout = io::stdout();
    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
    let backend = CrosstermBackend::new(stdout);
    let mut terminal = Terminal::new(backend)?;

    let result = render_loop(&mut terminal, rx, &mut app, &signals);

    // Disable mouse tracking before leaving the alternate screen.
    // Reversing this order causes mouse events buffered between LeaveAlternateScreen
    // and DisableMouseCapture to be printed as raw escape sequences in the shell.
    execute!(
        terminal.backend_mut(),
        DisableMouseCapture,
        LeaveAlternateScreen,
    )?;
    terminal::disable_raw_mode()?;
    terminal.show_cursor()?;
    result
}

fn render_loop<B: ratatui::backend::Backend>(
    terminal: &mut Terminal<B>,
    rx: LogRx,
    app: &mut state::AppState,
    signals: &DevSignals,
) -> io::Result<()> {
    use state::ShutdownPhase;
    let mut last_tick = Instant::now();
    loop {
        // Drain all pending events (non-blocking).
        loop {
            match rx.try_recv() {
                Ok(TuiEvent::Log(entry)) => app.push_log(entry),
                Ok(TuiEvent::Status {
                    source,
                    status,
                    detail,
                }) => app.update_service(source, status, detail),
                Err(_) => break,
            }
        }

        // Once the orchestrator signals shutdown is done, exit the render loop.
        if signals.shutdown_complete.load(Ordering::SeqCst) {
            app.shutdown_phase = ShutdownPhase::Done;
            terminal.draw(|f| render::draw(f, app))?;
            return Ok(());
        }

        terminal.draw(|f| render::draw(f, app))?;

        // While shutting down, skip keyboard processing — just keep rendering
        // progress until the orchestrator sets shutdown_complete.
        if app.shutdown_phase == ShutdownPhase::ShuttingDown {
            if last_tick.elapsed() >= TICK {
                last_tick = Instant::now();
            }
            continue;
        }

        // Poll keyboard/mouse for the remaining tick budget.
        let remaining = TICK.saturating_sub(last_tick.elapsed());
        if event::poll(remaining)? {
            match event::read()? {
                Event::Key(key) => {
                    if key.code == KeyCode::Char('c')
                        && key.modifiers.contains(KeyModifiers::CONTROL)
                    {
                        begin_shutdown(app, signals);
                    } else if app.search_input_active {
                        handle_search_input(key, app);
                    } else {
                        handle_normal(key, app, signals);
                    }
                }
                Event::Mouse(mouse_event) => {
                    handle_mouse(mouse_event, app);
                }
                _ => {}
            }
        }

        // Clear expired copy flash.
        if app
            .copy_flash
            .is_some_and(|t| t.elapsed() > std::time::Duration::from_secs(2))
        {
            app.copy_flash = None;
        }

        if last_tick.elapsed() >= TICK {
            last_tick = Instant::now();
        }
    }
}

/// Switch the TUI to shutdown display mode and signal the orchestrator.
fn begin_shutdown(app: &mut state::AppState, signals: &DevSignals) {
    use state::ShutdownPhase;
    if app.shutdown_phase != ShutdownPhase::Running {
        return;
    }
    app.shutdown_phase = ShutdownPhase::ShuttingDown;
    // Switch to System pane so shutdown log messages are immediately visible.
    app.active_pane = LogSource::System;
    app.scroll_bottom();
    app.clear_search();
    signals.quit_requested.store(true, Ordering::SeqCst);
}

/// Key handling while the search box is open.
fn handle_search_input(key: event::KeyEvent, app: &mut state::AppState) {
    let shift = key.modifiers.contains(KeyModifiers::SHIFT);
    match key.code {
        KeyCode::Enter | KeyCode::Esc => app.exit_search_input(),
        KeyCode::Backspace => app.search_backspace(),
        KeyCode::Up => {
            if shift { app.page_up() } else { app.scroll_up() }
        }
        KeyCode::Down => {
            if shift { app.page_down() } else { app.scroll_down() }
        }
        KeyCode::Char(c) => app.search_push(c),
        _ => {}
    }
}

/// Key handling in normal (non-search-input) mode.
fn handle_normal(key: event::KeyEvent, app: &mut state::AppState, signals: &DevSignals) {
    let shift = key.modifiers.contains(KeyModifiers::SHIFT);
    match key.code {
        KeyCode::Char('q') => begin_shutdown(app, signals),
        KeyCode::Char('/') => app.enter_search(),
        KeyCode::Esc => app.clear_search(),
        // Orchestrator signals.
        KeyCode::Char('r') => {
            signals.restart_requested.store(true, Ordering::SeqCst);
        }
        KeyCode::Char('b') => {
            signals.build_now_requested.store(true, Ordering::SeqCst);
        }
        // Pane navigation.
        KeyCode::Tab => app.cycle_pane(1),
        KeyCode::BackTab => app.cycle_pane(-1),
        KeyCode::Char('1') => app.active_pane = LogSource::System,
        KeyCode::Char('2') => app.active_pane = LogSource::Daemon,
        KeyCode::Char('3') => app.active_pane = LogSource::UiServer,
        KeyCode::Char('4') => app.active_pane = LogSource::Build,
        KeyCode::Char('5') => app.active_pane = LogSource::App,
        // Scrolling — Shift+↑/↓ pages, plain ↑/↓ lines.
        KeyCode::Up => {
            if shift { app.page_up() } else { app.scroll_up() }
        }
        KeyCode::Down => {
            if shift { app.page_down() } else { app.scroll_down() }
        }
        KeyCode::Char('g') => app.scroll_top(),
        KeyCode::Char('G') => app.scroll_bottom(),
        KeyCode::Char('c') => app.clear_active_pane(),
        _ => {}
    }
}

/// Copy text to the system clipboard.
/// Returns `true` if the clipboard command succeeded.
fn copy_to_clipboard(text: &str) -> bool {
    use std::io::Write as _;
    #[cfg(target_os = "macos")]
    {
        if let Ok(mut child) = std::process::Command::new("pbcopy")
            .stdin(std::process::Stdio::piped())
            .stdout(std::process::Stdio::null())
            .stderr(std::process::Stdio::null())
            .spawn()
        {
            if let Some(mut stdin) = child.stdin.take() {
                let _ = stdin.write_all(text.as_bytes());
            }
            return child.wait().map(|s| s.success()).unwrap_or(false);
        }
        false
    }
    #[cfg(target_os = "linux")]
    {
        for (cmd, args) in [
            ("wl-copy", vec![] as Vec<&str>),
            ("xclip", vec!["-selection", "clipboard"]),
        ] {
            if let Ok(mut child) = std::process::Command::new(cmd)
                .args(&args)
                .stdin(std::process::Stdio::piped())
                .stdout(std::process::Stdio::null())
                .stderr(std::process::Stdio::null())
                .spawn()
            {
                if let Some(mut stdin) = child.stdin.take() {
                    let _ = stdin.write_all(text.as_bytes());
                }
                if child.wait().map(|s| s.success()).unwrap_or(false) {
                    return true;
                }
            }
        }
        false
    }
    #[cfg(not(any(target_os = "macos", target_os = "linux")))]
    {
        let _ = text;
        false
    }
}

/// Handle a mouse event, updating app state accordingly.
fn handle_mouse(mouse: crossterm::event::MouseEvent, app: &mut state::AppState) {
    use crossterm::event::{MouseButton, MouseEventKind};
    use state::Selection;

    let col = mouse.column;
    let row = mouse.row;
    let layout = app.layout;

    // ── Mouse wheel: scroll anywhere in the right panel ────────────────────────
    let in_log_panel = col >= layout.tab_bar.x;
    match mouse.kind {
        MouseEventKind::ScrollUp if in_log_panel => {
            app.scroll_up();
            return;
        }
        MouseEventKind::ScrollDown if in_log_panel => {
            app.scroll_down();
            return;
        }
        _ => {}
    }

    // ── Click on tab bar ───────────────────────────────────────────────────────
    if row == layout.tab_bar.y
        && col >= layout.tab_bar.x
        && col < layout.tab_bar.x + layout.tab_bar.width
    {
        let sources = LogSource::all();
        for i in 0..sources.len() {
            let x_start = layout.tab_edges[i];
            let x_end = if i + 1 < sources.len() {
                layout.tab_edges[i + 1]
            } else {
                u16::MAX
            };
            if col >= x_start && col < x_end {
                if matches!(mouse.kind, MouseEventKind::Down(MouseButton::Left)) {
                    app.active_pane = sources[i];
                    app.auto_scroll = true;
                    app.clear_search();
                    app.selection = None;
                }
                return;
            }
        }
        return;
    }

    // ── Click in service list ──────────────────────────────────────────────────
    let sl = layout.service_list;
    if col >= sl.x && col < sl.x + sl.width && row >= sl.y && row < sl.y + sl.height {
        if matches!(mouse.kind, MouseEventKind::Down(MouseButton::Left)) && row > sl.y {
            // sl.y is the title row; items start at sl.y + 1, each 3 rows tall.
            let row_in_items = (row - sl.y - 1) as usize;
            let idx = row_in_items / 3;
            let sources = LogSource::all();
            if idx < sources.len() {
                app.active_pane = sources[idx];
                app.auto_scroll = true;
                app.clear_search();
                app.selection = None;
            }
        }
        return;
    }

    // ── Drag selection in log scroll area ─────────────────────────────────────
    let ls = layout.log_scroll;
    if col < ls.x || col >= ls.x + ls.width || row < ls.y || row >= ls.y + ls.height {
        return;
    }
    // Only support selection when no filter is active.
    if !app.search_query.is_empty() {
        return;
    }

    let row_in_area = (row - ls.y) as usize;
    let total = app.log_lines(app.active_pane).len();
    let line_idx = app.log_scroll_start + row_in_area;
    if line_idx >= total {
        return;
    }

    match mouse.kind {
        MouseEventKind::Down(MouseButton::Left) => {
            app.selection = Some(Selection { anchor: line_idx, head: line_idx });
            app.auto_scroll = false;
            if app.scroll_pos == 0 {
                app.scroll_pos = app.log_scroll_start;
            }
        }
        MouseEventKind::Drag(MouseButton::Left) => {
            if let Some(sel) = app.selection.as_mut() {
                sel.head = line_idx;
            }
        }
        MouseEventKind::Up(MouseButton::Left) => {
            if let Some(sel) = app.selection {
                // Copy on release (even single-line selections).
                let text = app.get_selected_text();
                if !text.is_empty() && copy_to_clipboard(&text) {
                    app.copy_flash = Some(std::time::Instant::now());
                }
                // Keep the selection visible so the user sees what was copied.
                let _ = sel;
            }
        }
        _ => {}
    }
}