fix: revive pane watcher no-handoff watchdog

src/bin/choir/init.mbt

@@ -471,8 +471,7 @@ fn init_default_terminal_session(project_dir : String) -> String {
 
 ///|
 fn init_config_toml_content() -> String {
-  "worker_no_handoff_prod_sec = 120\n" +
-  "worker_no_handoff_escalate_sec = 120\n" +
+  "worker_no_handoff_idle_sec = 120\n" +
   "auto_pull_after_integration = true\n" +
   "auto_rebuild_after_pull = false\n" +
   "auto_reload_after_rebuild = false\n" +
@@ -492,7 +491,7 @@ test "init config.toml scaffold omits machine local fields" {
   assert_false(content.contains("project_dir"))
   assert_false(content.contains("listen_uds"))
   assert_false(content.contains("terminal_session"))
-  assert_true(content.contains("worker_no_handoff_prod_sec = 120"))
+  assert_true(content.contains("worker_no_handoff_idle_sec = 120"))
   assert_true(content.contains("[pr_policy]"))
 }
 

src/bin/choir/uds_server.mbt

@@ -20,6 +20,23 @@ fn grow_connection_buffer(buf : FixedArray[Byte]) -> FixedArray[Byte] {
   next
 }
 
+///|
+async fn serve_dump_pane_screen(session : String, pane_id : String) -> String {
+  let (status, output) = @exec.capture_command_stdout(
+    @workspace.zellij_dump_screen_command(session, pane_id),
+  )
+  if status == 0 {
+    output
+  } else {
+    ""
+  }
+}
+
+///|
+fn serve_pane_watcher() -> @runtime.PaneWatcher {
+  @runtime.PaneWatcher::with_host({ dump_pane_screen: serve_dump_pane_screen })
+}
+
 ///|
 struct ServeUDSClient {
   fd : Int
@@ -1368,7 +1385,9 @@ fn serve_run() -> Unit {
     }
   }
   let provider = @server.make_recovery_provider()
-  let state = @server.ServerState::new(config, provider)
+  let state = @server.ServerState::new(config, provider).with_pane_watcher(
+    serve_pane_watcher(),
+  )
   @moontrace.set_global_field("service", "choir".to_json())
   @moontrace.set_global_field("run_id", state.run_id.to_json())
   @prompts.emit_prompt_drift_warnings(
@@ -1433,8 +1452,7 @@ fn serve_run() -> Unit {
               now,
               300L,
               @exec.run_sequence,
-              worker_no_handoff_prod_sec=config.worker_no_handoff_prod_sec,
-              worker_no_handoff_escalate_sec=config.worker_no_handoff_escalate_sec,
+              worker_no_handoff_idle_sec=config.worker_no_handoff_idle_sec,
             )
           } catch {
             e =>

src/config/config.mbt

@@ -554,23 +554,11 @@ pub fn parse_config(
     Ok(v) => v
     Err(e) => return Err(e)
   }
-  let worker_no_handoff_prod_sec = match doc.get("worker_no_handoff_prod_sec") {
-    None => default_cfg.worker_no_handoff_prod_sec
+  let worker_no_handoff_idle_sec = match doc.get("worker_no_handoff_idle_sec") {
+    None => default_cfg.worker_no_handoff_idle_sec
     Some(raw) =>
       match
-        parse_nonnegative_int64_config_value("worker_no_handoff_prod_sec", raw) {
-        Ok(v) => v
-        Err(e) => return Err(e)
-      }
-  }
-  let worker_no_handoff_escalate_sec = match
-    doc.get("worker_no_handoff_escalate_sec") {
-    None => default_cfg.worker_no_handoff_escalate_sec
-    Some(raw) =>
-      match
-        parse_nonnegative_int64_config_value(
-          "worker_no_handoff_escalate_sec", raw,
-        ) {
+        parse_nonnegative_int64_config_value("worker_no_handoff_idle_sec", raw) {
         Ok(v) => v
         Err(e) => return Err(e)
       }
@@ -677,8 +665,7 @@ pub fn parse_config(
     moon_verify_target,
     agy_migration_incomplete,
     hooks_enforcement,
-    worker_no_handoff_prod_sec,
-    worker_no_handoff_escalate_sec,
+    worker_no_handoff_idle_sec,
     poller_heartbeat_tick_sec,
     prenotify_checks,
     auto_pull_after_integration,

src/config/config_test.mbt

@@ -13,8 +13,7 @@ test "parse_config - full" {
     #|companions_json = '[{"name":"monitor","role":"worker","command":"claude","task":"Monitor the build"}]'
     #|plugins_json = '[{"name":"plugin","command":"./plugin","tools":"search"}]'
     #|hooks_enforcement = true
-    #|worker_no_handoff_prod_sec = 90
-    #|worker_no_handoff_escalate_sec = 45
+    #|worker_no_handoff_idle_sec = 90
     #|poller_heartbeat_tick_sec = 10
     #|prenotify_checks = ["moon check --target native", "CHOIR_TEST_NO_EXEC=1 moon test --target native", "CHOIR_TEST_REAL_EXEC=1 moon test --target native src/exec", "moon run src/bin/choir_lint --target native"]
     #|moon_verify_target = "js"
@@ -53,8 +52,7 @@ test "parse_config - full" {
       "[{\"name\":\"plugin\",\"command\":\"./plugin\",\"tools\":\"search\"}]",
     ),
   )
-  assert_eq(cfg.worker_no_handoff_prod_sec, 90L)
-  assert_eq(cfg.worker_no_handoff_escalate_sec, 45L)
+  assert_eq(cfg.worker_no_handoff_idle_sec, 90L)
   assert_eq(cfg.hooks_enforcement, true)
   assert_eq(cfg.poller_heartbeat_tick_sec, 10)
   @debug.assert_eq(cfg.prenotify_checks, [
@@ -149,8 +147,7 @@ test "parse_config - minimal" {
   assert_eq(cfg.automerge, false)
   assert_eq(cfg.review_mode, @types.ReviewMode::SinglePass)
   assert_eq(cfg.merge_strategy, @types.MergeStrategy::Merge)
-  assert_eq(cfg.worker_no_handoff_prod_sec, 120L)
-  assert_eq(cfg.worker_no_handoff_escalate_sec, 120L)
+  assert_eq(cfg.worker_no_handoff_idle_sec, 120L)
   assert_eq(cfg.hooks_enforcement, false)
   assert_eq(cfg.poller_heartbeat_tick_sec, 60)
   @debug.assert_eq(cfg.prenotify_checks, [])
@@ -336,32 +333,30 @@ test "parse_config pr_policy reviewer explicit copilot" {
 }
 
 ///|
-test "parse_config worker no-handoff knobs accept zero disable" {
+test "parse_config worker no-handoff idle knob accepts zero disable" {
   let cfg = parse_config(
     (
-      #|worker_no_handoff_prod_sec = 0
-      #|worker_no_handoff_escalate_sec = 0
+      #|worker_no_handoff_idle_sec = 0
       #|poller_heartbeat_tick_sec = 0
     ),
   ).unwrap()
-  assert_eq(cfg.worker_no_handoff_prod_sec, 0L)
-  assert_eq(cfg.worker_no_handoff_escalate_sec, 0L)
+  assert_eq(cfg.worker_no_handoff_idle_sec, 0L)
   assert_eq(cfg.poller_heartbeat_tick_sec, 0)
 }
 
 ///|
-test "parse_config worker no-handoff knobs reject negatives" {
-  match parse_config("worker_no_handoff_prod_sec = -1") {
+test "parse_config worker no-handoff idle knob rejects negatives" {
+  match parse_config("worker_no_handoff_idle_sec = -1") {
     Err(e) => assert_true(e.message().contains("expected >= 0"))
-    Ok(_) => fail("expected negative prod config to fail")
+    Ok(_) => fail("expected negative idle config to fail")
   }
 }
 
 ///|
-test "parse_config worker no-handoff knobs reject fractional values" {
-  match parse_config("worker_no_handoff_escalate_sec = 1.5") {
+test "parse_config worker no-handoff idle knob rejects fractional values" {
+  match parse_config("worker_no_handoff_idle_sec = 1.5") {
     Err(e) => assert_true(e.message().contains("expected integer"))
-    Ok(_) => fail("expected fractional escalate config to fail")
+    Ok(_) => fail("expected fractional idle config to fail")
   }
 }
 

src/runtime/pane_watch.mbt

@@ -1,26 +1,20 @@
 ///|
-/// Path for the zellij pane-viewport JSON snapshot for `agent_id` (under `/tmp`).
-pub fn pane_snapshot_path(agent_id : String) -> String {
-  "/tmp/choir-viewport-" + agent_id + ".json"
+pub(all) struct PaneWatchHost {
+  dump_pane_screen : async (String, String) -> String
 }
 
 ///|
-/// Host I/O for pane viewport subscribe: zellij child processes, pid cleanup, and snapshot files.
-pub(all) struct PaneWatchHost {
-  spawn_zellij_pane_viewport_subscribe : (String, String, String) -> Int
-  kill_pid_best_effort : (Int) -> Unit
-  delete_file_sync : (String) -> Unit
-  read_file : (String) -> String
+async fn native_dump_pane_screen(
+  _session : String,
+  _pane_id : String,
+) -> String {
+  @async.sleep(0)
+  ""
 }
 
 ///|
 pub fn PaneWatchHost::native() -> PaneWatchHost {
-  {
-    spawn_zellij_pane_viewport_subscribe: @sys.spawn_zellij_pane_viewport_subscribe,
-    kill_pid_best_effort: @sys.kill_pid_best_effort,
-    delete_file_sync: fn(path) { ignore(@sys.delete_file_sync(path)) },
-    read_file: @sys.read_file,
-  }
+  { dump_pane_screen: native_dump_pane_screen }
 }
 
 ///|
@@ -34,7 +28,8 @@ pub(all) struct WatchObservation {
 
 ///|
 pub(all) struct WatchState {
-  pid : Int
+  session : String
+  pane_id : String
   mut observation : WatchObservation
 }
 
@@ -66,84 +61,41 @@ pub fn PaneWatcher::watch_pane(
   agent_id : String,
   target : @types.LocalTarget,
   now : Int64,
+  pane_id? : String = "",
 ) -> Unit {
-  let snapshot_path = pane_snapshot_path(agent_id)
-  let pid = (self.host.spawn_zellij_pane_viewport_subscribe)(
-    target.session,
-    target.name,
-    snapshot_path,
-  )
-  if pid > 0 {
-    self.watches.set(agent_id, {
-      pid,
-      observation: { last_change_at: now, last_hash: 0, last_len: 0 },
-    })
+  let resolved = pane_id.trim().to_owned()
+  if resolved == "" {
+    return
   }
+  self.watches.set(agent_id, {
+    session: target.session,
+    pane_id: resolved,
+    observation: { last_change_at: now, last_hash: 0, last_len: 0 },
+  })
 }
 
 ///|
 pub fn PaneWatcher::stop_subscribe(
   self : PaneWatcher,
   agent_id : String,
 ) -> Unit {
-  match self.watches.get(agent_id) {
-    Some(watch) => {
-      self.watches.remove(agent_id)
-      (self.host.kill_pid_best_effort)(watch.pid)
-    }
-    None => ()
-  }
-  (self.host.delete_file_sync)(pane_snapshot_path(agent_id))
+  self.watches.remove(agent_id)
 }
 
 ///|
-pub fn PaneWatcher::read_viewport(
+pub async fn PaneWatcher::current_screen(
   self : PaneWatcher,
   agent_id : String,
-) -> String {
-  let snapshot_path = pane_snapshot_path(agent_id)
-  (self.host.read_file)(snapshot_path)
-}
-
-///|
-pub fn parse_int_simple(s : String) -> Int {
-  let mut result = 0
-  for c in s {
-    let d = c.to_int() - '0'.to_int()
-    if d >= 0 && d <= 9 {
-      result = result * 10 + d
-    }
-  }
-  result
-}
-
-///|
-/// Extract viewport text from a zellij subscribe JSON snapshot.
-/// Format: {"event":"pane_update","viewport":["line1","line2",...]}
-pub fn extract_viewport_text(json_str : String) -> String {
-  if json_str == "" {
-    return ""
+) -> String? {
+  let watch = match self.watches.get(agent_id) {
+    Some(watch) => watch
+    None => return None
   }
-  let parsed : Json = @json.parse(json_str) catch { _ => return json_str }
-  match parsed {
-    Object(obj) =>
-      match obj.get("viewport") {
-        Some(Array(lines)) => {
-          let buf = StringBuilder::new()
-          for line in lines {
-            match line {
-              String(s) => {
-                buf.write_string(s)
-                buf.write_char('\n')
-              }
-              _ => ()
-            }
-          }
-          buf.to_string()
-        }
-        _ => json_str
-      }
-    _ => json_str
+  let screen = (self.host.dump_pane_screen)(watch.session, watch.pane_id)
+  if screen.trim().to_owned() == "" {
+    None
+  } else {
+    Some(screen)
   }
 }
 
@@ -182,7 +134,7 @@ fn PaneWatcher::record_observation(
 /// Checks if the agent's pane has been idle. Returns `Some(screen_text)` if idle, `None` if not idle or not being watched.
 /// This is the pane-watch idle/no-heartbeat proxy signal; it emits no hard
 /// disconnect notification by itself.
-pub fn PaneWatcher::observe_idle(
+pub async fn PaneWatcher::observe_idle(
   self : PaneWatcher,
   agent_id : String,
   now : Int64,
@@ -191,11 +143,10 @@ pub fn PaneWatcher::observe_idle(
     Some(watch) => watch
     None => return None
   }
-  let snapshot = self.read_viewport(agent_id)
-  if snapshot.trim().to_owned() == "" {
+  let screen = (self.host.dump_pane_screen)(watch.session, watch.pane_id)
+  if screen.trim().to_owned() == "" {
     return None
   }
-  let screen = extract_viewport_text(snapshot)
   let hash = simple_hash(screen)
   let len = screen.length()
   let observation = watch.observation
@@ -213,7 +164,7 @@ pub fn PaneWatcher::observe_idle(
 /// Checks if the agent's pane has been idle. Returns `Some(screen_text)` if idle, `None` if not idle or not being watched.
 /// This is the pane-watch idle/no-heartbeat proxy signal; it emits no hard
 /// disconnect notification by itself.
-pub fn PaneWatcher::check_idle(
+pub async fn PaneWatcher::check_idle(
   self : PaneWatcher,
   agent_id : String,
   now : Int64,