vt: desktop notifications (OSC 9/777/99) and a configurable bell

Signed-off-by: NotAShelf <raf@notashelf.dev>
Change-Id: I43ad1f9892ecec1f32c03c67e863b1746a6a6964

src/config.rs

@@ -19,6 +19,7 @@ pub struct Config {
     pub mouse: Mouse,
     pub shell_integration: ShellIntegration,
     pub url: Url,
+    pub notify: Notify,
     /// Chord → action, e.g. `"Ctrl+Shift+C" = "copy"`. Merged over the defaults;
     /// a value of `"none"` unbinds.
     pub key_bindings: std::collections::HashMap<String, String>,
@@ -42,6 +43,27 @@ pub struct Cursor {
 pub struct Bell {
     /// Briefly flash the screen.
     pub visual: bool,
+    /// Command (argv) to run on the bell, e.g. `["paplay", "/usr/share/.../bell.oga"]`.
+    pub command: Vec<String>,
+    /// Request the compositor's attention (xdg-activation) when the bell rings
+    /// while the window is unfocused.
+    pub urgent: bool,
+}
+
+/// `[notify]`: how desktop notifications (OSC 9/777/99) are delivered.
+#[derive(Debug, Clone, Deserialize)]
+#[serde(default, rename_all = "kebab-case")]
+pub struct Notify {
+    /// Notifier argv; the title and body are appended as the last two arguments.
+    pub command: Vec<String>,
+}
+
+impl Default for Notify {
+    fn default() -> Self {
+        Self {
+            command: vec!["notify-send".to_string()],
+        }
+    }
 }
 
 /// `[mouse]`: pointer and wheel behaviour.

src/vt.rs

@@ -34,6 +34,14 @@ pub enum ClipboardOp {
     Query { primary: bool },
 }
 
+/// A desktop notification an application requested (OSC 9 / 777 / 99), for the
+/// front-end to deliver via the configured notifier.
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct Notification {
+    pub title: Option<String>,
+    pub body: String,
+}
+
 /// Which dynamic colour an OSC 10/11/17/19 escape targets.
 #[derive(Clone, Copy, Debug)]
 enum Dynamic {
@@ -106,6 +114,8 @@ pub struct Term {
     bell: bool,
     /// Working directory reported by the shell via OSC 7, for new windows.
     cwd: Option<String>,
+    /// Desktop notifications requested via OSC 9/777/99, drained by the front-end.
+    notifications: Vec<Notification>,
 }
 
 impl Term {
@@ -123,6 +133,7 @@ impl Term {
             theme: Theme::default(),
             bell: false,
             cwd: None,
+            notifications: Vec::new(),
         }
     }
 
@@ -131,6 +142,11 @@ impl Term {
         self.cwd.as_deref()
     }
 
+    /// Drain the desktop notifications requested since the last call.
+    pub fn take_notifications(&mut self) -> Vec<Notification> {
+        std::mem::take(&mut self.notifications)
+    }
+
     /// Take and clear the pending bell flag.
     pub fn take_bell(&mut self) -> bool {
         std::mem::take(&mut self.bell)
@@ -691,6 +707,27 @@ impl Perform for Term {
                 let uri = std::str::from_utf8(&uri_bytes).unwrap_or("");
                 self.grid.set_link((!uri.is_empty()).then_some(uri));
             }
+            // OSC 9: iTerm2-style notification (`OSC 9 ; body`).
+            Some(&n) if n == b"9" => {
+                if let Some(body) = osc_text(params.get(1)) {
+                    self.notifications.push(Notification { title: None, body });
+                }
+            }
+            // OSC 777: `OSC 777 ; notify ; title ; body`.
+            Some(&n) if n == b"777" && params.get(1) == Some(&&b"notify"[..]) => {
+                let title = osc_text(params.get(2));
+                if let Some(body) = osc_text(params.get(3)) {
+                    self.notifications.push(Notification { title, body });
+                }
+            }
+            // OSC 99: kitty desktop-notification protocol. We honour the common
+            // single-chunk form, taking the payload as the body and ignoring the
+            // metadata key=value field.
+            Some(&n) if n == b"99" => {
+                if let Some(body) = osc_text(params.get(2)).filter(|b| !b.is_empty()) {
+                    self.notifications.push(Notification { title: None, body });
+                }
+            }
             // OSC 4: set/query palette entries (pairs of index;spec).
             Some(&n) if n == b"4" => self.osc_palette(params, bell),
             // OSC 104: reset palette (all, or the listed indices).
@@ -834,6 +871,11 @@ fn base64_decode(data: &[u8]) -> Option<Vec<u8>> {
     Some(out)
 }
 
+/// Decode an OSC string field to UTF-8 (lossy), or `None` if absent.
+fn osc_text(field: Option<&&[u8]>) -> Option<String> {
+    field.map(|b| String::from_utf8_lossy(b).into_owned())
+}
+
 /// Map an OSC 133 mark letter to a [`PromptKind`].
 fn prompt_kind(b: u8) -> Option<PromptKind> {
     match b {
@@ -1158,6 +1200,28 @@ mod tests {
         assert_eq!(t.grid().last_command_output().as_deref(), Some("hi\n"));
     }
 
+    #[test]
+    fn osc_notifications_collected() {
+        let mut t = Term::new(20, 2);
+        feed(&mut t, b"\x1b]9;hello\x07");
+        feed(&mut t, b"\x1b]777;notify;Title;Body\x07");
+        let n = t.take_notifications();
+        assert_eq!(
+            n,
+            vec![
+                Notification {
+                    title: None,
+                    body: "hello".into()
+                },
+                Notification {
+                    title: Some("Title".into()),
+                    body: "Body".into()
+                },
+            ]
+        );
+        assert!(t.take_notifications().is_empty());
+    }
+
     #[test]
     fn osc7_tracks_cwd_and_decodes_percent() {
         let mut t = Term::new(20, 1);

src/wayland.rs

@@ -32,6 +32,7 @@ use smithay_client_toolkit::reexports::protocols::wp::primary_selection::zv1::cl
     zwp_primary_selection_source_v1::ZwpPrimarySelectionSourceV1,
 };
 use smithay_client_toolkit::{
+    activation::{ActivationHandler, ActivationState, RequestData},
     compositor::{CompositorHandler, CompositorState},
     data_device_manager::{
         DataDeviceManagerState, WritePipe,
@@ -39,7 +40,8 @@ use smithay_client_toolkit::{
         data_offer::{DataOfferHandler, DragOffer},
         data_source::{CopyPasteSource, DataSourceHandler},
     },
-    delegate_compositor, delegate_data_device, delegate_keyboard, delegate_output,
+        delegate_activation, delegate_compositor, delegate_data_device, delegate_keyboard,
+    delegate_output,
     delegate_pointer, delegate_primary_selection, delegate_registry, delegate_seat, delegate_shm,
     delegate_xdg_shell, delegate_xdg_window,
     output::{OutputHandler, OutputState},
@@ -224,6 +226,7 @@ pub fn run(config: Config, config_path: Option<std::path::PathBuf>) -> anyhow::R
             .map(|mgr| mgr.get_fractional_scale(window.wl_surface(), &qh, ()))
     });
     let text_input_manager = bind_global::<ZwpTextInputManagerV3>(&globals, &qh);
+    let activation = ActivationState::bind(&globals, &qh).ok();
 
     // First commit with no buffer kicks off the initial configure.
     window.commit();
@@ -261,6 +264,7 @@ pub fn run(config: Config, config_path: Option<std::path::PathBuf>) -> anyhow::R
         primary_manager,
         cursor_shape_manager,
         text_input_manager,
+        activation,
         preedit: String::new(),
         ime_preedit_pending: String::new(),
         ime_commit_pending: String::new(),
@@ -435,6 +439,8 @@ struct App {
     cursor_shape_manager: Option<CursorShapeManager>,
     /// IME manager (text-input-v3); per-seat handles live in `seats`.
     text_input_manager: Option<ZwpTextInputManagerV3>,
+    /// xdg-activation, used to request attention on an urgent bell.
+    activation: Option<ActivationState>,
     /// Committed IME preedit string shown inline at the cursor while composing.
     preedit: String,
     /// Preedit/commit accumulated since the last text-input `done`.
@@ -1569,15 +1575,78 @@ impl App {
         }
         let rang = session.term.take_bell();
         let ops = session.term.take_clipboard_ops();
+        let notifications = session.term.take_notifications();
         if !ops.is_empty() {
             self.handle_clipboard_ops(ops);
         }
-        if rang && self.config.bell.visual {
-            self.start_flash();
+        for note in notifications {
+            self.send_notification(&note);
+        }
+        if rang {
+            self.ring_bell();
         }
         self.needs_draw = true;
     }
 
+    /// React to a `BEL`: optionally flash, run the configured bell command, and
+    /// request the compositor's attention when unfocused.
+    fn ring_bell(&mut self) {
+        if self.config.bell.visual {
+            self.start_flash();
+        }
+        if let Some((program, args)) = self.config.bell.command.split_first() {
+            let _ = std::process::Command::new(program)
+                .args(args)
+                .stdin(std::process::Stdio::null())
+                .stdout(std::process::Stdio::null())
+                .stderr(std::process::Stdio::null())
+                .spawn()
+                .inspect_err(|err| tracing::warn!("bell command: {err}"));
+        }
+        if self.config.bell.urgent && !self.focused {
+            self.request_attention();
+        }
+    }
+
+    /// Deliver a desktop notification through the configured notifier (default
+    /// `notify-send`), appending the title and body as the final arguments.
+    fn send_notification(&self, note: &crate::vt::Notification) {
+        let Some((program, args)) = self.config.notify.command.split_first() else {
+            return;
+        };
+        let title = note
+            .title
+            .clone()
+            .or_else(|| self.title.clone())
+            .unwrap_or_else(|| "beer".to_string());
+        let _ = std::process::Command::new(program)
+            .args(args)
+            .arg(title)
+            .arg(&note.body)
+            .stdin(std::process::Stdio::null())
+            .stdout(std::process::Stdio::null())
+            .stderr(std::process::Stdio::null())
+            .spawn()
+            .inspect_err(|err| tracing::warn!("notify command: {err}"));
+    }
+
+    /// Ask the compositor to draw attention to the window (xdg-activation).
+    fn request_attention(&mut self) {
+        let Some(activation) = self.activation.as_ref() else {
+            return;
+        };
+        let seat_and_serial = self
+            .seats
+            .get(self.active_seat)
+            .map(|s| (s.seat.clone(), self.serial));
+        let data = smithay_client_toolkit::activation::RequestData {
+            app_id: Some("dev.notashelf.beer".to_string()),
+            seat_and_serial,
+            surface: Some(self.window.wl_surface().clone()),
+        };
+        activation.request_token::<App>(&self.qh, data);
+    }
+
     /// Begin a visual-bell flash: invert the screen for a moment. Clearing the
     /// buffer ring forces a full repaint with the inverted theme.
     fn start_flash(&mut self) {
@@ -2478,6 +2547,17 @@ impl Dispatch<WpViewport, ()> for App {
     }
 }
 
+impl ActivationHandler for App {
+    type RequestData = RequestData;
+
+    fn new_token(&mut self, token: String, _: &RequestData) {
+        // The compositor granted an activation token; use it to draw attention.
+        if let Some(activation) = self.activation.as_ref() {
+            activation.activate::<App>(self.window.wl_surface(), token);
+        }
+    }
+}
+
 impl Dispatch<ZwpTextInputManagerV3, ()> for App {
     fn event(
         _: &mut Self,
@@ -2542,3 +2622,4 @@ delegate_xdg_window!(App);
 delegate_data_device!(App);
 delegate_primary_selection!(App);
 delegate_registry!(App);
+delegate_activation!(App);