Wire breadmon into the bread event fabric (app id mon)

After a successful hyprctl apply, publish bread.mon.applied
{ "profile": <string or null> }. BreadClient is fail-silent: if
breadd is down, apply behaves exactly as before.

Document the contract in EVENTS.md.

src/bread_events.rs

@@ -0,0 +1,43 @@
+//! `bread.mon.*` event integration — optional, non-blocking. See
+//! `EVENTS.md` at the repo root for the full contract. breadmon works
+//! identically with or without breadd running; every call here is
+//! fire-and-forget (`BreadClient::emit` never blocks or errors this
+//! process) so a missing or restarting breadd never affects apply itself.
+
+use bread_utils::bread_client::BreadClient;
+use serde_json::{json, Value};
+
+/// This app's id in bread's sibling-app namespace registry
+/// (`bread_shared::apps::KNOWN_APPS`) — events publish as `bread.mon.*`.
+pub const APP_ID: &str = "mon";
+
+/// JSON payload for `bread.mon.applied`. `profile` is the named snapshot
+/// that was just applied, or `null` for an ad-hoc layout.
+pub fn applied_data(profile: Option<&str>) -> Value {
+    json!({ "profile": profile })
+}
+
+/// Publishes `bread.mon.applied` after a successful hyprctl apply.
+/// Fire-and-forget and non-fatal by design — breadd being absent or not
+/// installed must never affect breadmon's own apply path.
+pub fn emit_applied(profile: Option<&str>) {
+    BreadClient::connect(APP_ID).emit("bread.mon.applied", applied_data(profile));
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn applied_data_serializes_name_or_null() {
+        assert_eq!(applied_data(Some("dock")), json!({ "profile": "dock" }));
+        assert_eq!(applied_data(None), json!({ "profile": null }));
+    }
+
+    #[test]
+    fn emit_applied_is_silent_when_breadd_is_down() {
+        // No daemon in the unit-test environment; must not panic or block.
+        emit_applied(Some("dock"));
+        emit_applied(None);
+    }
+}

src/main.rs

@@ -1,3 +1,4 @@
+mod bread_events;
 mod layout;
 mod mirror;
 mod monitor;
@@ -135,6 +136,7 @@ async fn run(
                 if let Ok(monitors) = monitor::load_monitors().await {
                     state.monitors = monitors;
                     state.layout.clamp_selected(state.monitors.len());
+                    state.active_profile = None;
                     state.set_status("Monitor configuration changed.", StatusLevel::Info);
                 }
             }
@@ -166,6 +168,7 @@ async fn run(
                                 state.monitors = monitors;
                                 state.layout.clamp_selected(state.monitors.len());
                                 state.dirty = false;
+                                state.active_profile = None;
                                 state.set_status("Monitors refreshed.", StatusLevel::Success);
                             }
                             Err(e) => {
@@ -189,6 +192,7 @@ async fn run(
             state.pending_apply = false;
             match monitor::apply_monitors(&state.monitors).await {
                 Ok(()) => {
+                    bread_events::emit_applied(state.active_profile.as_deref());
                     state.set_status("Applied.", StatusLevel::Success);
                 }
                 Err(e) => {

src/ui/config_view.rs

@@ -239,7 +239,7 @@ fn handle_field_key(event: KeyEvent, state: &mut AppState) {
                     let m = &state.monitors[idx];
                     state.config.update_refreshes(m);
                     sync_mode_to_monitor(state, idx);
-                    state.dirty = true;
+                    state.mark_dirty();
                 }
             }
             KeyCode::Char('l') | KeyCode::Right
@@ -249,7 +249,7 @@ fn handle_field_key(event: KeyEvent, state: &mut AppState) {
                 let m = &state.monitors[idx];
                 state.config.update_refreshes(m);
                 sync_mode_to_monitor(state, idx);
-                state.dirty = true;
+                state.mark_dirty();
             }
             _ => {}
         },
@@ -258,7 +258,7 @@ fn handle_field_key(event: KeyEvent, state: &mut AppState) {
                 if state.config.refresh_idx > 0 {
                     state.config.refresh_idx -= 1;
                     sync_mode_to_monitor(state, idx);
-                    state.dirty = true;
+                    state.mark_dirty();
                 }
             }
             KeyCode::Char('l') | KeyCode::Right
@@ -266,7 +266,7 @@ fn handle_field_key(event: KeyEvent, state: &mut AppState) {
             {
                 state.config.refresh_idx += 1;
                 sync_mode_to_monitor(state, idx);
-                state.dirty = true;
+                state.mark_dirty();
             }
             _ => {}
         },
@@ -276,14 +276,14 @@ fn handle_field_key(event: KeyEvent, state: &mut AppState) {
                 state.monitors[idx].scale = (s * 100.0).round() / 100.0;
                 state.monitors[idx].scale = state.monitors[idx].scale.max(0.1);
                 state.config.scale_str = format!("{:.2}", state.monitors[idx].scale);
-                state.dirty = true;
+                state.mark_dirty();
             }
             KeyCode::Char('.') => {
                 let s = state.monitors[idx].scale + 0.1;
                 state.monitors[idx].scale = (s * 100.0).round() / 100.0;
                 state.monitors[idx].scale = state.monitors[idx].scale.min(10.0);
                 state.config.scale_str = format!("{:.2}", state.monitors[idx].scale);
-                state.dirty = true;
+                state.mark_dirty();
             }
             KeyCode::Char(c) if c.is_ascii_digit() || c == '.' => {
                 state.config.scale_editing = true;
@@ -303,27 +303,27 @@ fn handle_field_key(event: KeyEvent, state: &mut AppState) {
                     .checked_sub(1)
                     .unwrap_or(all.len() - 1);
                 state.monitors[idx].transform = all[state.config.transform_idx];
-                state.dirty = true;
+                state.mark_dirty();
             }
             KeyCode::Char('l') | KeyCode::Right => {
                 let all = Transform::all();
                 state.config.transform_idx = (state.config.transform_idx + 1) % all.len();
                 state.monitors[idx].transform = all[state.config.transform_idx];
-                state.dirty = true;
+                state.mark_dirty();
             }
             _ => {}
         },
         ConfigField::Vrr => match event.code {
             KeyCode::Char('h') | KeyCode::Left | KeyCode::Char('l') | KeyCode::Right | KeyCode::Char(' ') => {
                 state.monitors[idx].vrr = !state.monitors[idx].vrr;
-                state.dirty = true;
+                state.mark_dirty();
             }
             _ => {}
         },
         ConfigField::Dpms => match event.code {
             KeyCode::Char('h') | KeyCode::Left | KeyCode::Char('l') | KeyCode::Right | KeyCode::Char(' ') => {
                 state.monitors[idx].dpms = !state.monitors[idx].dpms;
-                state.dirty = true;
+                state.mark_dirty();
             }
             _ => {}
         },
@@ -332,7 +332,7 @@ fn handle_field_key(event: KeyEvent, state: &mut AppState) {
                 if state.config.mirror_idx > 0 {
                     state.config.mirror_idx -= 1;
                     sync_mirror_to_monitor(state, idx);
-                    state.dirty = true;
+                    state.mark_dirty();
                 }
             }
             KeyCode::Char('l') | KeyCode::Right
@@ -340,7 +340,7 @@ fn handle_field_key(event: KeyEvent, state: &mut AppState) {
             {
                 state.config.mirror_idx += 1;
                 sync_mirror_to_monitor(state, idx);
-                state.dirty = true;
+                state.mark_dirty();
             }
             _ => {}
         },
@@ -370,7 +370,7 @@ fn commit_scale(state: &mut AppState) {
     if let Ok(v) = state.config.scale_str.parse::<f64>() {
         state.monitors[idx].scale = v.clamp(0.1, 10.0);
         state.config.scale_str = format!("{:.2}", state.monitors[idx].scale);
-        state.dirty = true;
+        state.mark_dirty();
     }
     state.config.scale_editing = false;
 }

src/ui/layout_view.rs

@@ -22,22 +22,22 @@ pub fn handle_key(event: KeyEvent, state: &mut AppState) {
         KeyCode::Char('h') | KeyCode::Left => {
             state.push_undo();
             move_selected(&state.layout, &mut state.monitors, -step, 0);
-            state.dirty = true;
+            state.mark_dirty();
         }
         KeyCode::Char('l') | KeyCode::Right => {
             state.push_undo();
             move_selected(&state.layout, &mut state.monitors, step, 0);
-            state.dirty = true;
+            state.mark_dirty();
         }
         KeyCode::Char('k') | KeyCode::Up => {
             state.push_undo();
             move_selected(&state.layout, &mut state.monitors, 0, -step);
-            state.dirty = true;
+            state.mark_dirty();
         }
         KeyCode::Char('j') | KeyCode::Down => {
             state.push_undo();
             move_selected(&state.layout, &mut state.monitors, 0, step);
-            state.dirty = true;
+            state.mark_dirty();
         }
         KeyCode::Tab | KeyCode::Char('n') => state.layout.next(count),
         KeyCode::BackTab | KeyCode::Char('p') => state.layout.prev(count),
@@ -46,7 +46,7 @@ pub fn handle_key(event: KeyEvent, state: &mut AppState) {
         KeyCode::Char('0') => {
             state.push_undo();
             auto_arrange(&mut state.monitors);
-            state.dirty = true;
+            state.mark_dirty();
         }
         KeyCode::Enter => {
             state.config.sync_from_monitor(state.layout.selected, &state.monitors);
@@ -93,7 +93,7 @@ pub fn handle_mouse(event: MouseEvent, state: &mut AppState) {
                 let (sx, sy) = snap_position(idx, new_x, new_y, &state.monitors, state.layout.snap_threshold);
                 state.monitors[idx].x = sx;
                 state.monitors[idx].y = sy;
-                state.dirty = true;
+                state.mark_dirty();
             }
         }
         MouseEventKind::Up(MouseButton::Left) => {

src/ui/mirror_view.rs

@@ -137,7 +137,7 @@ pub fn handle_key(event: KeyEvent, state: &mut AppState) {
                     state.monitors[tgt_idx].active_mode = result.mirror_mode.clone();
                     state.monitors[tgt_idx].mirror_of = Some(src_name.clone());
 
-                    state.dirty = true;
+                    state.mark_dirty();
                     state.mirror.result = None;
                     state.mirror.focused = 0;
                     state.set_status(
@@ -225,7 +225,7 @@ pub fn handle_mouse(event: MouseEvent, state: &mut AppState) {
                             let tgt_idx = state.mirror.target_idx;
                             state.monitors[tgt_idx].active_mode = result.mirror_mode.clone();
                             state.monitors[tgt_idx].mirror_of = Some(src_name.clone());
-                            state.dirty = true;
+                            state.mark_dirty();
                             state.mirror.result = None;
                             state.mirror.focused = 0;
                             state.set_status(

src/ui/mod.rs

@@ -111,6 +111,10 @@ pub struct AppState {
     pub terminal_size: (u16, u16),
     /// Set to true by any handler that wants `main.rs` to run `apply_monitors`.
     pub pending_apply: bool,
+    /// Named snapshot last loaded or saved this session. Cleared when the
+    /// in-memory layout is edited, so `bread.mon.applied` can report it
+    /// honestly (or `null` for an ad-hoc layout).
+    pub active_profile: Option<String>,
     /// Snapshots for Ctrl+Z undo (up to 20 deep).
     pub undo_stack: Vec<Vec<Monitor>>,
 }
@@ -131,6 +135,7 @@ impl AppState {
             drag_state: None,
             terminal_size,
             pending_apply: false,
+            active_profile: None,
             undo_stack: Vec::new(),
         }
     }
@@ -139,6 +144,14 @@ impl AppState {
         self.status = Some(StatusMsg { text: text.into(), level, born: Instant::now() });
     }
 
+    /// Mark the in-memory layout as edited. Also forgets `active_profile`
+    /// — a mutated layout is no longer the named snapshot that was loaded
+    /// or saved.
+    pub fn mark_dirty(&mut self) {
+        self.dirty = true;
+        self.active_profile = None;
+    }
+
     pub fn tick_status(&mut self) {
         if let Some(s) = &self.status {
             if s.born.elapsed().as_secs() >= 3 {
@@ -166,7 +179,7 @@ impl AppState {
     pub fn undo(&mut self) {
         if let Some(snapshot) = self.undo_stack.pop() {
             self.monitors = snapshot;
-            self.dirty = true;
+            self.mark_dirty();
             self.layout.clamp_selected(self.monitors.len());
             // Re-sync config view to the restored state
             let idx = self.layout.selected;

src/ui/profiles_view.rs

@@ -240,6 +240,7 @@ fn do_save(state: &mut AppState) {
         Ok(()) => {
             state.profiles.new_name.clear();
             state.profiles.refresh();
+            state.active_profile = Some(name.clone());
             state.set_status(format!("Saved profile '{}'", name), StatusLevel::Success);
         }
         Err(e) => {
@@ -254,6 +255,7 @@ fn do_load(state: &mut AppState) {
         Ok(p) => {
             profile::apply_to_monitors(&p, &mut state.monitors);
             state.dirty = true;
+            state.active_profile = Some(name.clone());
             state.set_status(
                 format!("Loaded profile '{}'. Press [a] to apply.", name),
                 StatusLevel::Success,