feat(v2): add RemoteManager for multi-machine WebSocket connections

New remote.rs module in src-tauri with WebSocket client connections to
bterminal-relay instances. Machine lifecycle: add/remove/connect/
disconnect. 12 new Tauri commands for remote operations. Heartbeat
ping every 15s. lib.rs updated with remote commands and AppState.

v2/src-tauri/src/remote.rs

@@ -0,0 +1,358 @@
+// Remote machine management — WebSocket client connections to bterminal-relay instances
+
+use bterminal_core::pty::PtyOptions;
+use bterminal_core::sidecar::AgentQueryOptions;
+use futures_util::{SinkExt, StreamExt};
+use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
+use std::sync::Arc;
+use tauri::{AppHandle, Emitter};
+use tokio::sync::{Mutex, mpsc};
+use tokio_tungstenite::tungstenite::Message;
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct RemoteMachineConfig {
+    pub label: String,
+    pub url: String,
+    pub token: String,
+    pub auto_connect: bool,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct RemoteMachineInfo {
+    pub id: String,
+    pub label: String,
+    pub url: String,
+    pub status: String,
+    pub auto_connect: bool,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+struct RelayCommand {
+    id: String,
+    #[serde(rename = "type")]
+    type_: String,
+    payload: serde_json::Value,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+struct RelayEvent {
+    #[serde(rename = "type")]
+    type_: String,
+    #[serde(rename = "sessionId")]
+    session_id: Option<String>,
+    #[serde(rename = "machineId")]
+    machine_id: Option<String>,
+    payload: Option<serde_json::Value>,
+}
+
+struct WsConnection {
+    tx: mpsc::UnboundedSender<String>,
+    _handle: tokio::task::JoinHandle<()>,
+}
+
+struct RemoteMachine {
+    id: String,
+    config: RemoteMachineConfig,
+    status: String,
+    connection: Option<WsConnection>,
+}
+
+pub struct RemoteManager {
+    machines: Arc<Mutex<HashMap<String, RemoteMachine>>>,
+}
+
+impl RemoteManager {
+    pub fn new() -> Self {
+        Self {
+            machines: Arc::new(Mutex::new(HashMap::new())),
+        }
+    }
+
+    pub fn list_machines(&self) -> Vec<RemoteMachineInfo> {
+        // Use try_lock for sync context (called from Tauri command handler)
+        let machines = self.machines.try_lock();
+        match machines {
+            Ok(m) => m.values().map(|m| RemoteMachineInfo {
+                id: m.id.clone(),
+                label: m.config.label.clone(),
+                url: m.config.url.clone(),
+                status: m.status.clone(),
+                auto_connect: m.config.auto_connect,
+            }).collect(),
+            Err(_) => Vec::new(),
+        }
+    }
+
+    pub fn add_machine(&self, config: RemoteMachineConfig) -> String {
+        let id = uuid::Uuid::new_v4().to_string();
+        let machine = RemoteMachine {
+            id: id.clone(),
+            config,
+            status: "disconnected".to_string(),
+            connection: None,
+        };
+        // Use try_lock for sync context
+        if let Ok(mut machines) = self.machines.try_lock() {
+            machines.insert(id.clone(), machine);
+        }
+        id
+    }
+
+    pub fn remove_machine(&self, machine_id: &str) -> Result<(), String> {
+        let mut machines = self.machines.try_lock()
+            .map_err(|_| "Lock contention".to_string())?;
+        machines.remove(machine_id)
+            .ok_or_else(|| format!("Machine {machine_id} not found"))?;
+        Ok(())
+    }
+
+    pub async fn connect(&self, app: &AppHandle, machine_id: &str) -> Result<(), String> {
+        let (url, token) = {
+            let mut machines = self.machines.lock().await;
+            let machine = machines.get_mut(machine_id)
+                .ok_or_else(|| format!("Machine {machine_id} not found"))?;
+            if machine.connection.is_some() {
+                return Err("Already connected".to_string());
+            }
+            machine.status = "connecting".to_string();
+            (machine.config.url.clone(), machine.config.token.clone())
+        };
+
+        // Build WebSocket request with auth header
+        let request = tokio_tungstenite::tungstenite::http::Request::builder()
+            .uri(&url)
+            .header("Authorization", format!("Bearer {token}"))
+            .header("Sec-WebSocket-Key", tokio_tungstenite::tungstenite::handshake::client::generate_key())
+            .header("Sec-WebSocket-Version", "13")
+            .header("Connection", "Upgrade")
+            .header("Upgrade", "websocket")
+            .header("Host", extract_host(&url).unwrap_or_default())
+            .body(())
+            .map_err(|e| format!("Failed to build request: {e}"))?;
+
+        let (ws_stream, _) = tokio_tungstenite::connect_async(request)
+            .await
+            .map_err(|e| format!("WebSocket connect failed: {e}"))?;
+
+        let (mut ws_tx, mut ws_rx) = ws_stream.split();
+
+        // Channel for sending messages to the WebSocket
+        let (send_tx, mut send_rx) = mpsc::unbounded_channel::<String>();
+
+        // Writer task — forwards channel messages to WebSocket
+        let writer_handle = tokio::spawn(async move {
+            while let Some(msg) = send_rx.recv().await {
+                if ws_tx.send(Message::Text(msg)).await.is_err() {
+                    break;
+                }
+            }
+        });
+
+        // Reader task — forwards WebSocket messages to Tauri events
+        let app_handle = app.clone();
+        let mid = machine_id.to_string();
+        let machines_ref = self.machines.clone();
+        let reader_handle = tokio::spawn(async move {
+            while let Some(msg) = ws_rx.next().await {
+                match msg {
+                    Ok(Message::Text(text)) => {
+                        if let Ok(mut event) = serde_json::from_str::<RelayEvent>(&text) {
+                            event.machine_id = Some(mid.clone());
+                            // Route relay events to Tauri events
+                            match event.type_.as_str() {
+                                "sidecar_message" => {
+                                    if let Some(payload) = &event.payload {
+                                        let _ = app_handle.emit("remote-sidecar-message", &serde_json::json!({
+                                            "machineId": mid,
+                                            "sessionId": event.session_id,
+                                            "event": payload,
+                                        }));
+                                    }
+                                }
+                                "pty_data" => {
+                                    if let Some(payload) = &event.payload {
+                                        let _ = app_handle.emit("remote-pty-data", &serde_json::json!({
+                                            "machineId": mid,
+                                            "sessionId": event.session_id,
+                                            "data": payload,
+                                        }));
+                                    }
+                                }
+                                "pty_exit" => {
+                                    let _ = app_handle.emit("remote-pty-exit", &serde_json::json!({
+                                        "machineId": mid,
+                                        "sessionId": event.session_id,
+                                    }));
+                                }
+                                "ready" => {
+                                    let _ = app_handle.emit("remote-machine-ready", &serde_json::json!({
+                                        "machineId": mid,
+                                    }));
+                                }
+                                "state_sync" => {
+                                    let _ = app_handle.emit("remote-state-sync", &serde_json::json!({
+                                        "machineId": mid,
+                                        "payload": event.payload,
+                                    }));
+                                }
+                                "pong" => {} // heartbeat response, ignore
+                                "error" => {
+                                    let _ = app_handle.emit("remote-error", &serde_json::json!({
+                                        "machineId": mid,
+                                        "error": event.payload,
+                                    }));
+                                }
+                                _ => {
+                                    log::warn!("Unknown relay event type: {}", event.type_);
+                                }
+                            }
+                        }
+                    }
+                    Ok(Message::Close(_)) => break,
+                    Err(e) => {
+                        log::error!("WebSocket read error for machine {mid}: {e}");
+                        break;
+                    }
+                    _ => {}
+                }
+            }
+
+            // Mark disconnected
+            if let Ok(mut machines) = machines_ref.try_lock() {
+                if let Some(machine) = machines.get_mut(&mid) {
+                    machine.status = "disconnected".to_string();
+                    machine.connection = None;
+                }
+            }
+            let _ = app_handle.emit("remote-machine-disconnected", &serde_json::json!({
+                "machineId": mid,
+            }));
+        });
+
+        // Combine reader + writer into one handle
+        let combined_handle = tokio::spawn(async move {
+            tokio::select! {
+                _ = reader_handle => {}
+                _ = writer_handle => {}
+            }
+        });
+
+        // Store connection
+        let mut machines = self.machines.lock().await;
+        if let Some(machine) = machines.get_mut(machine_id) {
+            machine.status = "connected".to_string();
+            machine.connection = Some(WsConnection {
+                tx: send_tx,
+                _handle: combined_handle,
+            });
+        }
+
+        // Start heartbeat
+        let ping_tx = {
+            let machines = self.machines.lock().await;
+            machines.get(machine_id).and_then(|m| m.connection.as_ref().map(|c| c.tx.clone()))
+        };
+        if let Some(tx) = ping_tx {
+            let mid = machine_id.to_string();
+            tokio::spawn(async move {
+                let mut interval = tokio::time::interval(std::time::Duration::from_secs(15));
+                loop {
+                    interval.tick().await;
+                    let ping = serde_json::json!({"id": "", "type": "ping", "payload": {}});
+                    if tx.send(ping.to_string()).is_err() {
+                        log::info!("Heartbeat stopped for machine {mid}");
+                        break;
+                    }
+                }
+            });
+        }
+
+        Ok(())
+    }
+
+    pub async fn disconnect(&self, machine_id: &str) -> Result<(), String> {
+        let mut machines = self.machines.lock().await;
+        let machine = machines.get_mut(machine_id)
+            .ok_or_else(|| format!("Machine {machine_id} not found"))?;
+        if let Some(conn) = machine.connection.take() {
+            conn._handle.abort();
+        }
+        machine.status = "disconnected".to_string();
+        Ok(())
+    }
+
+    // --- Remote command helpers ---
+
+    async fn send_command(&self, machine_id: &str, cmd: RelayCommand) -> Result<(), String> {
+        let machines = self.machines.lock().await;
+        let machine = machines.get(machine_id)
+            .ok_or_else(|| format!("Machine {machine_id} not found"))?;
+        let conn = machine.connection.as_ref()
+            .ok_or_else(|| format!("Machine {machine_id} not connected"))?;
+        let json = serde_json::to_string(&cmd)
+            .map_err(|e| format!("Serialize error: {e}"))?;
+        conn.tx.send(json)
+            .map_err(|_| format!("Send channel closed for machine {machine_id}"))
+    }
+
+    pub async fn agent_query(&self, machine_id: &str, options: &AgentQueryOptions) -> Result<(), String> {
+        self.send_command(machine_id, RelayCommand {
+            id: uuid::Uuid::new_v4().to_string(),
+            type_: "agent_query".to_string(),
+            payload: serde_json::to_value(options).unwrap_or_default(),
+        }).await
+    }
+
+    pub async fn agent_stop(&self, machine_id: &str, session_id: &str) -> Result<(), String> {
+        self.send_command(machine_id, RelayCommand {
+            id: uuid::Uuid::new_v4().to_string(),
+            type_: "agent_stop".to_string(),
+            payload: serde_json::json!({ "sessionId": session_id }),
+        }).await
+    }
+
+    pub async fn pty_spawn(&self, machine_id: &str, options: &PtyOptions) -> Result<String, String> {
+        // Send spawn command; the relay will respond with the PTY ID via a relay event
+        let cmd_id = uuid::Uuid::new_v4().to_string();
+        self.send_command(machine_id, RelayCommand {
+            id: cmd_id.clone(),
+            type_: "pty_create".to_string(),
+            payload: serde_json::to_value(options).unwrap_or_default(),
+        }).await?;
+        // Return the command ID as a placeholder; the real PTY ID comes via event
+        Ok(cmd_id)
+    }
+
+    pub async fn pty_write(&self, machine_id: &str, id: &str, data: &str) -> Result<(), String> {
+        self.send_command(machine_id, RelayCommand {
+            id: uuid::Uuid::new_v4().to_string(),
+            type_: "pty_write".to_string(),
+            payload: serde_json::json!({ "id": id, "data": data }),
+        }).await
+    }
+
+    pub async fn pty_resize(&self, machine_id: &str, id: &str, cols: u16, rows: u16) -> Result<(), String> {
+        self.send_command(machine_id, RelayCommand {
+            id: uuid::Uuid::new_v4().to_string(),
+            type_: "pty_resize".to_string(),
+            payload: serde_json::json!({ "id": id, "cols": cols, "rows": rows }),
+        }).await
+    }
+
+    pub async fn pty_kill(&self, machine_id: &str, id: &str) -> Result<(), String> {
+        self.send_command(machine_id, RelayCommand {
+            id: uuid::Uuid::new_v4().to_string(),
+            type_: "pty_close".to_string(),
+            payload: serde_json::json!({ "id": id }),
+        }).await
+    }
+}
+
+fn extract_host(url: &str) -> Option<String> {
+    url.replace("wss://", "")
+        .replace("ws://", "")
+        .split('/')
+        .next()
+        .map(|s| s.to_string())
+}