feat(ssh): validate terminal emulator support

Makes controls usable by taking SSH keystroke data (encoded in the xterm
format) and converting them to crossterm `KeyCode`s / `KeyEvent`s and
sending them to the `Tui`.

Also adds support for suspension of the `Tui` over the SSH connection.

Some minor refactoring was also done.

.config/config.json5

@@ -4,6 +4,7 @@
       "<q>": "Quit", // Quit the application
       "<Ctrl-d>": "Quit", // Another way to quit
       "<Ctrl-c>": "Quit", // Yet another way to quit
+      "<Esc>": "Quit", // Final way to quit
       "<Ctrl-z>": "Suspend" // Suspend the application
     },
   }

src/app.rs

@@ -1,16 +1,21 @@
 use std::sync::Arc;
 
-use color_eyre::Result;
-use crossterm::event::KeyEvent;
+use color_eyre::{eyre, Result};
+use crossterm::event::{KeyCode, KeyEvent};
 use ratatui::prelude::Rect;
 use serde::{Deserialize, Serialize};
-use tokio::sync::{mpsc, Mutex};
+use tokio::{
+    sync::{mpsc, Mutex, RwLock},
+    task::block_in_place,
+};
+use tokio_util::sync::CancellationToken;
 use tracing::{debug, info};
 
 use crate::{
     action::Action,
     components::{fps::FpsCounter, home::Home, Component},
     config::Config,
+    keycode::KeyCodeExt,
     tui::{Event, Terminal, Tui},
 };
 
@@ -25,6 +30,7 @@ pub struct App {
     last_tick_key_events: Vec<KeyEvent>,
     action_tx: mpsc::UnboundedSender<Action>,
     action_rx: mpsc::UnboundedReceiver<Action>,
+    ssh_rx: mpsc::UnboundedReceiver<Vec<u8>>,
 }
 
 #[derive(Default, Debug, Copy, Clone, PartialEq, Eq, Hash, Serialize, Deserialize)]
@@ -34,7 +40,11 @@ pub enum Mode {
 }
 
 impl App {
-    pub fn new(tick_rate: f64, frame_rate: f64) -> Result<Self> {
+    pub fn new(
+        tick_rate: f64,
+        frame_rate: f64,
+        ssh_rx: mpsc::UnboundedReceiver<Vec<u8>>,
+    ) -> Result<Self> {
         let (action_tx, action_rx) = mpsc::unbounded_channel();
         Ok(Self {
             tick_rate,
@@ -50,74 +60,104 @@ impl App {
             last_tick_key_events: Vec::new(),
             action_tx,
             action_rx,
+            ssh_rx,
         })
     }
 
-    pub async fn run(&mut self, term: Arc<Mutex<Terminal>>) -> Result<()> {
-        let mut tui = Tui::new(term)?
-            // .mouse(true) // uncomment this line to enable mouse support
-            .tick_rate(self.tick_rate)
-            .frame_rate(self.frame_rate);
-        
-        tokio::task::block_in_place(|| tui.enter())?;
+    pub async fn run(
+        &mut self,
+        term: Arc<Mutex<Terminal>>,
+        tui: Arc<RwLock<Option<Tui>>>,
+    ) -> Result<()> {
+        let mut tui = tui.write().await;
+        let mut tui = tui.get_or_insert(
+            Tui::new(term)?
+                // .mouse(true) // uncomment this line to enable mouse support
+                .tick_rate(self.tick_rate)
+                .frame_rate(self.frame_rate),
+        );
 
-        for component in self.components.iter_mut() {
-            component
-                .try_lock()?
-                .register_action_handler(self.action_tx.clone())?;
-        }
-        for component in self.components.iter_mut() {
-            component
-                .try_lock()?
-                .register_config_handler(self.config.clone())?;
-        }
-        for component in self.components.iter_mut() {
-            component
-                .try_lock()?
-                .init(tui.terminal.try_lock()?.size()?)?;
-        }
+        // Blocking initialization logic for tui and components
+        block_in_place(|| {
+            tui.enter()?;
+
+            for component in self.components.iter_mut() {
+                component
+                    .try_lock()?
+                    .register_action_handler(self.action_tx.clone())?;
+            }
+
+            for component in self.components.iter_mut() {
+                component
+                    .try_lock()?
+                    .register_config_handler(self.config.clone())?;
+            }
+
+            for component in self.components.iter_mut() {
+                component
+                    .try_lock()?
+                    .init(tui.terminal.try_lock()?.size()?)?;
+            }
+
+            Ok::<_, eyre::Error>(())
+        })?;
 
         let action_tx = self.action_tx.clone();
+        let mut resume_tx: Option<Arc<CancellationToken>> = None;
         loop {
             self.handle_events(&mut tui).await?;
             // self.handle_actions(&mut tui)?;
-            tokio::task::block_in_place(|| self.handle_actions(&mut tui))?;
+            block_in_place(|| self.handle_actions(&mut tui))?;
             if self.should_suspend {
-                tui.suspend()?;
+                if let Some(ref tx) = resume_tx {
+                    tx.cancel(); 
+                    resume_tx = None;
+                } else {
+                    resume_tx = Some(tui.suspend().await?);
+                    continue
+                }
                 action_tx.send(Action::Resume)?;
                 action_tx.send(Action::ClearScreen)?;
                 // tui.mouse(true);
-                tui.enter()?;
+                block_in_place(|| tui.enter())?;
             } else if self.should_quit {
-                tui.stop()?;
+                block_in_place(|| tui.stop())?;
                 break;
             }
         }
-        tui.exit()?;
-        Ok(())
+
+        block_in_place(|| tui.exit())
     }
 
     async fn handle_events(&mut self, tui: &mut Tui) -> Result<()> {
-        let Some(event) = tui.next_event().await else {
-            return Ok(());
-        };
-        let action_tx = self.action_tx.clone();
-        match event {
-            Event::Quit => action_tx.send(Action::Quit)?,
-            Event::Tick => action_tx.send(Action::Tick)?,
-            Event::Render => action_tx.send(Action::Render)?,
-            Event::Resize(x, y) => action_tx.send(Action::Resize(x, y))?,
-            Event::Key(key) => self.handle_key_event(key)?,
-            _ => {}
-        }
-        for component in self.components.iter_mut() {
-            if let Some(action) = component.try_lock()?.handle_events(Some(event.clone()))? {
-                action_tx.send(action)?;
+        tokio::select! {
+            Some(event) = tui.next_event() => {
+                // Wait for next event and fire required actions for components
+                let action_tx = self.action_tx.clone();
+                match event {
+                    Event::Quit => action_tx.send(Action::Quit)?,
+                    Event::Tick => action_tx.send(Action::Tick)?,
+                    Event::Render => action_tx.send(Action::Render)?,
+                    Event::Resize(x, y) => action_tx.send(Action::Resize(x, y))?,
+                    Event::Key(key) => block_in_place(|| self.handle_key_event(key))?,
+                    _ => {}
+                };
+
+                for component in self.components.iter_mut() {
+                    let mut component = component.try_lock()?;
+                    if let Some(action) = block_in_place(|| component.handle_events(Some(event.clone())))? {
+                        action_tx.send(action)?;
+                    }
+                }
+            }
+            Some(ssh_data) = self.ssh_rx.recv() => {
+                // Receive keystroke data from SSH connection
+                let key_event = KeyCode::from_xterm_seq(&ssh_data[..]).into_key_event();
+                block_in_place(|| self.handle_key_event(key_event))?;
             }
         }
         Ok(())
     }
-
     fn handle_key_event(&mut self, key: KeyEvent) -> Result<()> {
         let action_tx = self.action_tx.clone();
         let Some(keymap) = self.config.keybindings.get(&self.mode) else {
@@ -130,7 +170,7 @@ impl App {
             }
             _ => {
                 // If the key was not handled as a single key action,
-                // then consider it for multi-key combinations.
+                // then consider it for multi-key combinations
                 self.last_tick_key_events.push(key);
 
                 // Check for multi-key combinations

src/keycode.rs

@@ -0,0 +1,171 @@
+use crossterm::event::{KeyCode, KeyEvent, KeyModifiers};
+
+pub const CTRL_C: char = 3 as char;
+pub const CTRL_D: char = 4 as char;
+pub const CTRL_Z: char = 26 as char;
+
+pub trait KeyCodeExt {
+    /// Create a [KeyCode] from a keystroke byte.
+    fn from(code: u8) -> KeyCode;
+    /// Create a [KeyCode] from a xterm byte sequence of keystroke data.
+    fn from_xterm_seq(seq: &[u8]) -> KeyCode;
+    /// Consume the [KeyCode], converting it into a [KeyEvent].
+    fn into_key_event(self) -> KeyEvent;
+}
+
+impl KeyCodeExt for KeyCode {
+    fn from(code: u8) -> KeyCode {
+        match code {
+            // Control sequences (non exhaustive)
+            3 => Self::Char(CTRL_C),
+            4 => Self::Char(CTRL_D),
+            26 => Self::Char(CTRL_Z),
+
+            // Common control characters
+            8 => KeyCode::Backspace,
+            9 => KeyCode::Tab,
+            13 => KeyCode::Enter,
+            27 => KeyCode::Esc,
+
+            // Arrow keys
+            37 => KeyCode::Left,
+            38 => KeyCode::Up,
+            39 => KeyCode::Right,
+            40 => KeyCode::Down,
+
+            // Navigation keys
+            33 => KeyCode::PageUp,
+            34 => KeyCode::PageDown,
+            36 => KeyCode::Home,
+            35 => KeyCode::End,
+            45 => KeyCode::Insert,
+            46 => KeyCode::Delete,
+
+            // Menu key
+            93 => KeyCode::Menu,
+
+            // Printable ASCII characters
+            b' '..=b'~' => KeyCode::Char(code as char),
+
+            // Special characters
+            127 => KeyCode::Backspace,
+
+            // Caps/Num/Scroll Lock
+            20 => KeyCode::CapsLock,
+            144 => KeyCode::NumLock,
+            145 => KeyCode::ScrollLock, 
+
+            // Pause/Break
+            19 => KeyCode::Pause,
+
+            // Anything else
+            0 | _ => KeyCode::Null,
+        }    
+    }
+
+    #[rustfmt::skip]
+    fn from_xterm_seq(seq: &[u8]) -> Self {
+        let codes = seq
+            .iter()
+            .map(|&b| <Self as KeyCodeExt>::from(b))
+            .collect::<Vec<Self>>();
+        
+        match codes.as_slice() {
+            [Self::Esc, Self::Char('['), Self::Char('A')] => Self::Up,
+            [Self::Esc, Self::Char('['), Self::Char('B')] => Self::Down,
+            [Self::Esc, Self::Char('['), Self::Char('C')] => Self::Right,
+            [Self::Esc, Self::Char('['), Self::Char('D')] => Self::Left,
+            [Self::Esc, Self::Char('['), Self::Char('1'), Self::Char('~')] => Self::Home,
+            [Self::Esc, Self::Char('['), Self::Char('4'), Self::Char('~')] => Self::End,
+            [Self::Esc, Self::Char('['), Self::Char('3'), Self::Char('~')] => Self::Delete,
+            [Self::Esc, Self::Char('['), Self::Char('5'), Self::Char('~')] => Self::PageUp,
+            [Self::Esc, Self::Char('['), Self::Char('6'), Self::Char('~')] => Self::PageDown,
+            [Self::Esc, Self::Char('O'), Self::Char('P')] => Self::F(1),
+            [Self::Esc, Self::Char('O'), Self::Char('Q')] => Self::F(2),
+            [Self::Esc, Self::Char('O'), Self::Char('R')] => Self::F(3),
+            [Self::Esc, Self::Char('O'), Self::Char('S')] => Self::F(4),
+            [Self::Esc, Self::Char('['), Self::Char('1'), Self::Char('5'), Self::Char('~')] => Self::F(5),
+            [Self::Esc, Self::Char('['), Self::Char('1'), Self::Char('7'), Self::Char('~')] => Self::F(6),
+            [Self::Esc, Self::Char('['), Self::Char('1'), Self::Char('8'), Self::Char('~')] => Self::F(7),
+            [Self::Esc, Self::Char('['), Self::Char('1'), Self::Char('9'), Self::Char('~')] => Self::F(8),
+            [Self::Esc, Self::Char('['), Self::Char('2'), Self::Char('0'), Self::Char('~')] => Self::F(9),
+            [Self::Esc, Self::Char('['), Self::Char('2'), Self::Char('1'), Self::Char('~')] => Self::F(10),
+            [Self::Esc, Self::Char('['), Self::Char('2'), Self::Char('3'), Self::Char('~')] => Self::F(11),
+            [Self::Esc, Self::Char('['), Self::Char('2'), Self::Char('4'), Self::Char('~')] => Self::F(12),
+            [single] => *single,
+            _ => KeyCode::Null,
+        }
+    }    
+
+    fn into_key_event(self) -> KeyEvent {
+        match self {
+            Self::Char(CTRL_C) => KeyEvent::new(KeyCode::Char('c'), KeyModifiers::CONTROL),
+            Self::Char(CTRL_D) => KeyEvent::new(KeyCode::Char('d'), KeyModifiers::CONTROL),
+            Self::Char(CTRL_Z) => KeyEvent::new(KeyCode::Char('z'), KeyModifiers::CONTROL),
+            other => KeyEvent::new(other, KeyModifiers::empty()),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_keycode_from_control_chars() {
+        assert_eq!(<KeyCode as KeyCodeExt>::from(8), KeyCode::Backspace);
+        assert_eq!(<KeyCode as KeyCodeExt>::from(9), KeyCode::Tab);
+        assert_eq!(<KeyCode as KeyCodeExt>::from(13), KeyCode::Enter);
+        assert_eq!(<KeyCode as KeyCodeExt>::from(27), KeyCode::Esc);
+    }
+
+    #[test]
+    fn test_keycode_from_printable_ascii() {
+        assert_eq!(<KeyCode as KeyCodeExt>::from(b'a'), KeyCode::Char('a'));
+        assert_eq!(<KeyCode as KeyCodeExt>::from(b'Z'), KeyCode::Char('Z'));
+        assert_eq!(<KeyCode as KeyCodeExt>::from(b'0'), KeyCode::Char('0'));
+        assert_eq!(<KeyCode as KeyCodeExt>::from(b'~'), KeyCode::Char('~'));
+    }
+
+    #[test]
+    fn test_keycode_from_special_keys() {
+        assert_eq!(<KeyCode as KeyCodeExt>::from(20), KeyCode::CapsLock);
+        assert_eq!(<KeyCode as KeyCodeExt>::from(144), KeyCode::NumLock);
+        assert_eq!(<KeyCode as KeyCodeExt>::from(145), KeyCode::ScrollLock);
+        assert_eq!(<KeyCode as KeyCodeExt>::from(19), KeyCode::Pause);
+        assert_eq!(<KeyCode as KeyCodeExt>::from(0), KeyCode::Null);
+    }
+
+    #[test]
+    fn test_keycode_from_invalid() {
+        assert_eq!(<KeyCode as KeyCodeExt>::from(255), KeyCode::Null);
+        assert_eq!(<KeyCode as KeyCodeExt>::from(200), KeyCode::Null);
+    }
+
+    #[test]
+    fn test_keycode_from_seq() {
+        assert_eq!(<KeyCode as KeyCodeExt>::from_xterm_seq(&[65]), KeyCode::Char('A'));
+        assert_eq!(<KeyCode as KeyCodeExt>::from_xterm_seq(&[27]), KeyCode::Esc);
+        assert_eq!(<KeyCode as KeyCodeExt>::from_xterm_seq(&[0]), KeyCode::Null);
+
+        assert_eq!(<KeyCode as KeyCodeExt>::from_xterm_seq(&[27, 91, 68]), KeyCode::Left);
+        assert_eq!(<KeyCode as KeyCodeExt>::from_xterm_seq(&[27, 91, 67]), KeyCode::Right);
+        assert_eq!(<KeyCode as KeyCodeExt>::from_xterm_seq(&[27, 91, 65]), KeyCode::Up);
+        assert_eq!(<KeyCode as KeyCodeExt>::from_xterm_seq(&[27, 91, 66]), KeyCode::Down); 
+
+        assert_eq!(<KeyCode as KeyCodeExt>::from_xterm_seq(&[27, 91, 53, 126]), KeyCode::PageUp);
+        assert_eq!(<KeyCode as KeyCodeExt>::from_xterm_seq(&[27, 91, 54, 126]), KeyCode::PageDown);
+        assert_eq!(<KeyCode as KeyCodeExt>::from_xterm_seq(&[27, 91, 51, 126]), KeyCode::Delete);
+        assert_eq!(<KeyCode as KeyCodeExt>::from_xterm_seq(&[27, 91, 52, 126]), KeyCode::End);
+
+        assert_eq!(<KeyCode as KeyCodeExt>::from_xterm_seq(&[27, 91, 49, 56, 126]), KeyCode::F(7));
+        assert_eq!(<KeyCode as KeyCodeExt>::from_xterm_seq(&[27, 91, 49, 57, 126]), KeyCode::F(8));
+    }
+
+    #[test]
+    fn test_into_key_event() {
+        let key_code = KeyCode::Char('a');
+        let key_event = <KeyCode as KeyCodeExt>::into_key_event(key_code);
+        assert_eq!(key_event, KeyEvent::new(KeyCode::Char('a'), KeyModifiers::empty()));
+    }
+}

src/main.rs

@@ -14,6 +14,7 @@ mod errors;
 mod logging;
 mod ssh;
 mod tui;
+mod keycode;
 
 const SOCKET_ADDR: LazyLock<SocketAddr> = LazyLock::new(|| SocketAddr::from(([127, 0, 0, 1], 2222)));
 pub static SSH_CONFIG: OnceLock<Arc<Config>> = OnceLock::new();

src/ssh.rs

@@ -1,15 +1,22 @@
 use std::{io::Write, net::SocketAddr, sync::Arc};
 
 use async_trait::async_trait;
+use color_eyre::eyre::eyre;
 use ratatui::prelude::CrosstermBackend;
 use russh::{
     server::{Auth, Handle, Handler, Msg, Server, Session},
-    Channel, ChannelId, CryptoVec, Pty,
+    Channel, ChannelId, CryptoVec, Pty, 
+};
+use tokio::{
+    runtime::Handle as TokioHandle,
+    sync::{mpsc, Mutex, RwLock},
 };
-use tokio::{runtime::Handle as TokioHandle, sync::Mutex};
 use tracing::instrument;
 
-use crate::{app::App, tui::Terminal};
+use crate::{
+    app::App,
+    tui::{Terminal, Tui},
+};
 
 #[derive(Debug)]
 pub struct TermWriter {
@@ -27,6 +34,19 @@ impl TermWriter {
             inner: CryptoVec::new(),
         }
     }
+
+    fn flush_inner(&mut self) -> std::io::Result<()> {
+        let handle = TokioHandle::current();
+        handle.block_on(async move {
+            self.session
+                .data(self.channel.id(), self.inner.clone())
+                .await
+                .map_err(|err| {
+                    std::io::Error::other(String::from_iter(err.iter().map(|item| *item as char)))
+                })
+                .and_then(|()| Ok(self.inner.clear()))
+        })
+    }
 }
 
 impl Write for TermWriter {
@@ -38,32 +58,29 @@ impl Write for TermWriter {
 
     #[instrument(skip(self), level = "trace")]
     fn flush(&mut self) -> std::io::Result<()> {
-        let handle = TokioHandle::current();
-        handle.block_on(async move {
-            self.session
-                .data(self.channel.id(), self.inner.clone())
-                .await
-                .map_err(|err| {
-                    std::io::Error::other(String::from_iter(err.iter().map(|item| *item as char)))
-                })?;
-
-            self.inner.clear();
-            Ok(())
-        })
+        tokio::task::block_in_place(|| self.flush_inner())
     }
 }
 
-pub struct SshSession(Option<Arc<Mutex<App>>>);
+pub struct SshSession {
+    app: Option<Arc<Mutex<App>>>,
+    ssh_tx: mpsc::UnboundedSender<Vec<u8>>,
+    tui: Arc<RwLock<Option<Tui>>>,
+}
 
 unsafe impl Send for SshSession {}
 
 impl SshSession {
     pub fn new() -> Self {
-        Self(
-            App::new(10f64, 60f64)
+        let (ssh_tx, ssh_rx) = mpsc::unbounded_channel();
+
+        Self {
+            app: App::new(10f64, 60f64, ssh_rx)
                 .ok()
                 .map(|app| Arc::new(Mutex::new(app))),
-        )
+            tui: Arc::new(RwLock::new(None)),
+            ssh_tx,
+        }
     }
 }
 
@@ -82,24 +99,27 @@ impl Handler for SshSession {
         channel: Channel<Msg>,
         session: &mut Session,
     ) -> Result<bool, Self::Error> {
-        if let Some(app) = &self.0 {
+        if let Some(app) = &self.app {
+            let session_handle = session.handle();
+            let channel_id = channel.id();
+
             let inner_app = Arc::clone(app);
             let term = Terminal::new(CrosstermBackend::new(TermWriter::new(session, channel)))?;
             let writer = Arc::new(Mutex::new(term));
-            
+            let tui = Arc::clone(&self.tui);
+
             tokio::task::spawn(async move {
-                inner_app.lock_owned().await.run(writer).await.unwrap();
+                inner_app.lock_owned().await.run(writer, tui).await.unwrap();
+                session_handle.close(channel_id).await.unwrap();
+                session_handle.exit_status_request(channel_id, 0).await.unwrap();
             });
 
             return Ok(true);
         }
 
-        return Err(color_eyre::eyre::eyre!(
-            "Failed to initialize App for session"
-        ));
+        Err(eyre!("Failed to initialize App for session"))
     }
-
-    #[instrument(skip(self, _session), level = "trace")]
+    #[instrument(skip(self, session), level = "trace")]
     async fn pty_request(
         &mut self,
         channel_id: ChannelId,
@@ -109,11 +129,30 @@ impl Handler for SshSession {
         pix_width: u32,
         pix_height: u32,
         modes: &[(Pty, u32)],
+        session: &mut Session,
+    ) -> Result<(), Self::Error> {
+        tracing::info!("Received pty request from channel {channel_id}; terminal: {term}");
+        tracing::debug!("dims: {col_width} * {row_height}, pixel: {pix_width} * {pix_height}");
+        
+        if !term.contains("xterm") {
+            session.channel_failure(channel_id)?;
+            return Err(eyre!("Unsupported terminal type: {term}"));
+        }
+
+        Ok(())
+    }
+
+    #[instrument(skip(self, _session), level = "trace")]
+    async fn data(
+        &mut self,
+        _channel: ChannelId,
+        data: &[u8],
         _session: &mut Session,
     ) -> Result<(), Self::Error> {
-        tracing::info!("received pty request from channel {channel_id}");
-        tracing::debug!("dims: {col_width} * {row_height}, pixel: {pix_width} * {pix_height}");
-        Ok(())
+        tracing::debug!("Received keystroke data from SSH: {:?}, sending", data);
+        self.ssh_tx
+            .send(data.to_vec())
+            .map_err(|_| eyre!("Failed to send event keystroke data"))
     }
 }
 
@@ -127,7 +166,6 @@ impl Server for SshServer {
     #[instrument(skip(self))]
     fn new_client(&mut self, peer_addr: Option<SocketAddr>) -> Self::Handler {
         let session = SshSession::new();
-        // self.0.push((peer_addr.unwrap(), session));
         session
     }
 }

src/tui/mod.rs

@@ -1,4 +1,4 @@
-#![allow(dead_code)] // Remove this once you start using the code
+#![allow(dead_code)] // TODO: Remove this once you start using the code
 
 use std::{sync::Arc, time::Duration};
 
@@ -7,17 +7,17 @@ use crossterm::{
     cursor,
     event::{
         DisableBracketedPaste, DisableMouseCapture, EnableBracketedPaste, EnableMouseCapture,
-        Event as CrosstermEvent, EventStream, KeyEvent, KeyEventKind, MouseEvent,
+        KeyEvent, MouseEvent,
     },
     terminal::{EnterAlternateScreen, LeaveAlternateScreen},
 };
-use futures::{FutureExt, StreamExt};
 use ratatui::backend::CrosstermBackend as Backend;
 use serde::{Deserialize, Serialize};
+use status::TuiStatus;
 use tokio::{
     sync::{
         mpsc::{self, UnboundedReceiver, UnboundedSender},
-        Mutex,
+        Mutex, RwLock,
     },
     task::JoinHandle,
     time::interval,
@@ -27,6 +27,8 @@ use tracing::error;
 
 use crate::ssh::TermWriter;
 
+pub(crate) mod status;
+
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub enum Event {
     Init,
@@ -50,6 +52,8 @@ pub struct Tui {
     pub cancellation_token: CancellationToken,
     pub event_rx: UnboundedReceiver<Event>,
     pub event_tx: UnboundedSender<Event>,
+    pub resume_tx: Option<UnboundedSender<()>>,
+    pub status: Arc<RwLock<TuiStatus>>,
     pub frame_rate: f64,
     pub tick_rate: f64,
     pub mouse: bool,
@@ -65,6 +69,8 @@ impl Tui {
             cancellation_token: CancellationToken::new(),
             event_rx,
             event_tx,
+            resume_tx: Option::None,
+            status: Arc::new(RwLock::new(TuiStatus::Active)),
             frame_rate: 60.0,
             tick_rate: 4.0,
             mouse: false,
@@ -96,6 +102,7 @@ impl Tui {
         self.cancel(); // Cancel any existing task
         self.cancellation_token = CancellationToken::new();
         let event_loop = Self::event_loop(
+            self.status.clone(),
             self.event_tx.clone(),
             self.cancellation_token.clone(),
             self.tick_rate,
@@ -107,12 +114,12 @@ impl Tui {
     }
 
     async fn event_loop(
+        status: Arc<RwLock<TuiStatus>>,
         event_tx: UnboundedSender<Event>,
         cancellation_token: CancellationToken,
         tick_rate: f64,
         frame_rate: f64,
     ) {
-        let mut event_stream = EventStream::new();
         let mut tick_interval = interval(Duration::from_secs_f64(1.0 / tick_rate));
         let mut render_interval = interval(Duration::from_secs_f64(1.0 / frame_rate));
 
@@ -120,27 +127,18 @@ impl Tui {
         event_tx
             .send(Event::Init)
             .expect("failed to send init event");
+
+        let suspension_status = Arc::clone(&status);
         loop {
+            let _guard = suspension_status.read().await;
             let event = tokio::select! {
                 _ = cancellation_token.cancelled() => {
                     break;
                 }
                 _ = tick_interval.tick() => Event::Tick,
                 _ = render_interval.tick() => Event::Render,
-                crossterm_event = event_stream.next().fuse() => match crossterm_event {
-                    Some(Ok(event)) => match event {
-                        CrosstermEvent::Key(key) if key.kind == KeyEventKind::Press => Event::Key(key),
-                        CrosstermEvent::Mouse(mouse) => Event::Mouse(mouse),
-                        CrosstermEvent::Resize(x, y) => Event::Resize(x, y),
-                        CrosstermEvent::FocusLost => Event::FocusLost,
-                        CrosstermEvent::FocusGained => Event::FocusGained,
-                        CrosstermEvent::Paste(s) => Event::Paste(s),
-                        _ => continue, // ignore other events
-                    }
-                    Some(Err(_)) => Event::Error,
-                    None => break, // the event stream has stopped and will not produce any more events
-                },
             };
+
             if event_tx.send(event).is_err() {
                 // the receiver has been dropped, so there's no point in continuing the loop
                 break;
@@ -180,6 +178,7 @@ impl Tui {
         }
 
         drop(term);
+
         self.start();
         Ok(())
     }
@@ -209,16 +208,32 @@ impl Tui {
         self.cancellation_token.cancel();
     }
 
-    pub fn suspend(&mut self) -> Result<()> {
-        self.exit()?;
-        #[cfg(not(windows))]
-        signal_hook::low_level::raise(signal_hook::consts::signal::SIGTSTP)?;
-        Ok(())
-    }
+    pub async fn suspend(&mut self) -> Result<Arc<CancellationToken>> {
+        // Exit the current Tui
+        tokio::task::block_in_place(|| self.exit())?;
 
-    pub fn resume(&mut self) -> Result<()> {
-        self.enter()?;
-        Ok(())
+        // Update the status and initialize a cancellation token
+        let token = Arc::new(CancellationToken::new());
+        let suspension = Arc::new(Mutex::new(()));
+        *self.status.write().await = TuiStatus::Suspended(Arc::clone(&suspension));
+
+        // Spawn a task holding on the lock until a notification interrupts it
+        let status = Arc::clone(&self.status);
+        let lock_release = Arc::clone(&token);
+        tokio::task::spawn(async move {
+            tokio::select! {
+                _ = lock_release.cancelled() => {
+                    // Lock was released, update the status
+                    *status.write().await = TuiStatus::Active;
+                }
+                _ = tokio::time::sleep(tokio::time::Duration::from_secs(u64::MAX)) => {
+                    // Hold on to the lock until notified
+                    let _ = suspension.lock().await;
+                }
+            }
+        });
+
+        Ok(token)
     }
 
     pub async fn next_event(&mut self) -> Option<Event> {
@@ -226,20 +241,6 @@ impl Tui {
     }
 }
 
-// impl Deref for Tui {
-//     type Target = ratatui::Terminal<Backend<TermWriter>>;
-
-//     fn deref(&self) -> &Self::Target {
-//         self.terminal.as_ref()
-//     }
-// }
-
-// impl DerefMut for Tui {
-//     fn deref_mut(&mut self) -> &mut Self::Target {
-//         self.terminal.get_mut().unwrap()
-//     }
-// }
-
 impl Drop for Tui {
     fn drop(&mut self) {
         self.exit().unwrap();

src/tui/status.rs

@@ -0,0 +1,25 @@
+use std::{future::{Future, IntoFuture}, pin::Pin, sync::Arc};
+
+use futures::future;
+use tokio::sync::Mutex;
+
+#[derive(Debug, Clone)]
+pub enum TuiStatus {
+    Active,
+    Suspended(Arc<Mutex<()>>),
+}
+
+impl IntoFuture for TuiStatus {
+    type Output = ();
+    type IntoFuture = Pin<Box<dyn Future<Output = Self::Output>>>;
+
+    fn into_future(self) -> Self::IntoFuture {
+        if let Self::Suspended(lock) = self {
+            return Box::pin(async move {
+                let _guard = lock.lock().await;
+            });
+        }
+
+        Box::pin(future::ready(()))
+    }
+}