fix: ignore stale callbacks from rescheduled timers

- Add generation counters to SmartCondition and EventSensor timers.
- Preserve pending changes and the retention period when timers are restarted.
- Silently cancel timers that have already expired.
- Add regression tests for stale callbacks and expiry during cancellation.

smartcondition.py

@@ -46,6 +46,7 @@ class Evaluator():
         self.__state_callbacks_handle = list()
         self.__condition_state_change_delayed = list()
         self.__condition_state_change_delayed_cb_handle = None
+        self.__delay_generation = 0
 
         self.__appdaemon_api = appdaemon_api
         self.__activated = False
@@ -573,6 +574,10 @@ class Evaluator():
             self.__last_evaluation_result = result
 
     def __on_condition_state_change_delayed(self, kwargs):
+        # An expired timer may already be queued when a newer change reschedules it.
+        # Ignore it before touching the current timer handle or pending changes.
+        if kwargs.get("generation") != self.__delay_generation:
+            return
         self.__condition_state_change_delayed_cb_handle = None
         if len(self.__condition_state_change_delayed) == 0:
             self.__log(f"Callback has been trigger but self.__condition_state_change_delayed is empty, this shouldn't happen, the callback won't be called", level = "WARNING")
@@ -607,13 +612,18 @@ class Evaluator():
                 #     self.__update_result()
                 self.__trigger_callbacks(f"Callback trigger by {entity}({old} => {new})")
             else:
-                if self.__condition_state_change_delayed_cb_handle != None and self.__appdaemon_api.timer_running(self.__condition_state_change_delayed_cb_handle): 
-                    self.__appdaemon_api.cancel_timer(self.__condition_state_change_delayed_cb_handle)
+                self.__delay_generation += 1
+                handle = self.__condition_state_change_delayed_cb_handle
+                if handle is not None:
+                    # Expiry may already have removed the timer from the scheduler.
+                    self.__appdaemon_api.cancel_timer(handle, silent=True)
                     self.__condition_state_change_delayed_cb_handle = None
 
                 self.__condition_state_change_delayed.append((entity,old,new,datetime.now()))
-                #self.__log("State changed :" + str(entity) + "(" + str(old) + " => " + str(new) + ") but callback delayed for " + str(self.__callback_delay) + "s")
-                self.__condition_state_change_delayed_cb_handle = self.__appdaemon_api.run_in(self.__on_condition_state_change_delayed, self.__callback_delay)
+                self.__condition_state_change_delayed_cb_handle = self.__appdaemon_api.run_in(
+                    self.__on_condition_state_change_delayed, self.__callback_delay,
+                    generation=self.__delay_generation,
+                )
 
     def __log(self,message,**kwargs):
         log_string = self.__log_to_string(message)

unit_tests/test_event_sensor.py

@@ -0,0 +1,79 @@
+"""An expired timer queued before reactivation must not end the new window."""
+import ast
+from pathlib import Path
+from types import SimpleNamespace
+import unittest
+from unittest.mock import Mock
+
+from test_continuous_condition import FakeScheduler
+
+source = Path(__file__).resolve().parents[1] / 'virtualsensors.py'
+node = next(node for node in ast.parse(source.read_text()).body
+            if isinstance(node, ast.ClassDef) and node.name == 'EventSensor')
+namespace = {'VirtualSensorBase': object, 'EventHandler': Mock()}
+exec(compile(ast.Module(body=[node], type_ignores=[]), str(source), 'exec'), namespace)
+EventSensor = namespace['EventSensor']
+
+
+class EventSensorTests(unittest.TestCase):
+    def setUp(self):
+        self.scheduler = FakeScheduler()
+        self.state = 'off'
+        entity = Mock()
+        entity.exists.return_value = True
+        entity.set_state.side_effect = lambda *, state: setattr(self, 'state', state)
+        self.sensor = EventSensor()
+        self.sensor.ad_api = SimpleNamespace(
+            get_entity=lambda name: entity,
+            run_in=self.scheduler.run_in,
+            cancel_timer=self.scheduler.cancel_timer,
+        )
+        self.sensor.sensor_name = 'binary_sensor.red_shelly_home'
+        self.sensor.yaml_block = {'retain_time': 120}
+        self.sensor.initialize()
+
+    def activate(self):
+        self.sensor.on_activation_event('signal_strength', {}, {})
+        return self.sensor.cb_handle
+
+    def test_current_expiry_turns_sensor_off(self):
+        handle = self.activate()
+        self.assertEqual(self.state, 'on')
+        self.scheduler.expire(handle)()
+        self.assertEqual(self.state, 'off')
+        self.assertIsNone(self.sensor.cb_handle)
+
+    def test_reactivation_cancels_running_timer(self):
+        old = self.activate()
+        current = self.activate()
+        self.assertNotIn(old, self.scheduler.timers)
+        self.assertIn(current, self.scheduler.timers)
+        self.assertEqual(self.state, 'on')
+        self.assertEqual(self.scheduler.warnings, [])
+
+    def test_queued_expiry_preserves_reactivated_sensor_and_timer(self):
+        queued = self.scheduler.expire(self.activate())
+        current = self.activate()
+        queued()
+        self.assertEqual(self.state, 'on')
+        self.assertEqual(self.sensor.cb_handle, current)
+        self.assertEqual(self.scheduler.warnings, [])
+        self.scheduler.expire(current)()
+        self.assertEqual(self.state, 'off')
+        self.assertIsNone(self.sensor.cb_handle)
+
+    def test_multiple_queued_expiries_cannot_end_latest_window(self):
+        first = self.scheduler.expire(self.activate())
+        second = self.scheduler.expire(self.activate())
+        current = self.activate()
+        second()
+        first()
+        self.assertEqual(self.state, 'on')
+        self.assertEqual(self.sensor.cb_handle, current)
+        self.assertEqual(self.scheduler.warnings, [])
+        self.scheduler.expire(current)()
+        self.assertEqual(self.state, 'off')
+
+
+if __name__ == '__main__':
+    unittest.main()

unit_tests/test_smartcondition_delay.py

@@ -0,0 +1,122 @@
+"""Verify debouncing when an expired AppDaemon timer is still queued."""
+import sys
+import unittest
+from pathlib import Path
+from unittest.mock import Mock
+
+sys.path.insert(0, str(Path(__file__).resolve().parents[1]))
+from smartcondition import Evaluator
+
+
+class FakeScheduler:
+    def __init__(self):
+        self.timers = {}
+        self.next_id = 0
+        self.cancelled = []
+        self.warnings = []
+        self.expire_on_cancel = False
+        self.queued = []
+
+    def run_in(self, callback, delay, **kwargs):
+        self.next_id += 1
+        handle = str(self.next_id)
+        self.timers[handle] = (callback, kwargs)
+        return handle
+
+    def timer_running(self, handle):
+        return handle in self.timers
+
+    def cancel_timer(self, handle, silent=False):
+        self.cancelled.append(handle)
+        if self.expire_on_cancel and handle in self.timers:
+            self.queued.append(self.expire(handle))
+        cancelled = self.timers.pop(handle, None) is not None
+        if not cancelled and not silent:
+            self.warnings.append(handle)
+        return cancelled
+
+    def expire(self, handle):
+        callback, kwargs = self.timers.pop(handle)
+        return lambda: callback(kwargs)
+
+
+class DelayedCallbackTests(unittest.TestCase):
+    def setUp(self):
+        self.scheduler = FakeScheduler()
+        self.evaluator = Evaluator.__new__(Evaluator)
+        fields = dict(
+            appdaemon_api=self.scheduler, callback_delay=10,
+            trigger_callback_on_entity_creation=True,
+            condition_state_change_delayed=[],
+            condition_state_change_delayed_cb_handle=None,
+            delay_generation=0, trigger_callbacks=Mock(), log=Mock(),
+        )
+        for name, value in fields.items():
+            setattr(self.evaluator, '_Evaluator__' + name, value)
+
+    def change(self, old, new):
+        self.evaluator._Evaluator__on_condition_state_change(
+            'sensor.temperature', 'state', old, new, {})
+        return self.evaluator._Evaluator__condition_state_change_delayed_cb_handle
+
+    def test_queued_obsolete_callback_preserves_new_timer_and_changes(self):
+        old_handle = self.change('20', '21')
+        queued_callback = self.scheduler.expire(old_handle)
+        new_handle = self.change('21', '22')
+        queued_callback()
+        self.assertEqual(self.scheduler.warnings, [])
+
+        self.assertEqual(self.evaluator._Evaluator__condition_state_change_delayed_cb_handle,
+                         new_handle)
+        self.assertEqual(len(self.evaluator._Evaluator__condition_state_change_delayed), 2)
+        self.evaluator._Evaluator__trigger_callbacks.assert_not_called()
+        self.evaluator._Evaluator__log.assert_not_called()
+
+        self.scheduler.expire(new_handle)()
+        self.evaluator._Evaluator__trigger_callbacks.assert_called_once()
+        reason = self.evaluator._Evaluator__trigger_callbacks.call_args.args[0]
+        self.assertIn('20 => 21', reason)
+        self.assertIn('21 => 22', reason)
+        self.assertEqual(self.evaluator._Evaluator__condition_state_change_delayed, [])
+        self.assertIsNone(self.evaluator._Evaluator__condition_state_change_delayed_cb_handle)
+        self.evaluator._Evaluator__log.assert_not_called()
+
+    def test_obsolete_callback_after_current_callback_is_ignored(self):
+        queued_callback = self.scheduler.expire(self.change('20', '21'))
+        self.scheduler.expire(self.change('21', '22'))()
+        queued_callback()
+        self.evaluator._Evaluator__trigger_callbacks.assert_called_once()
+        self.evaluator._Evaluator__log.assert_not_called()
+
+    def test_running_timer_is_cancelled_when_rescheduled(self):
+        old_handle = self.change('20', '21')
+        new_handle = self.change('21', '22')
+        self.assertEqual(self.scheduler.cancelled, [old_handle])
+        self.assertFalse(self.scheduler.timer_running(old_handle))
+        self.scheduler.expire(new_handle)()
+        self.evaluator._Evaluator__trigger_callbacks.assert_called_once()
+
+    def test_expiry_during_cancellation_is_silent_and_preserves_new_batch(self):
+        self.change('20', '21')
+        self.scheduler.expire_on_cancel = True
+        current = self.change('21', '22')
+        self.assertEqual(self.scheduler.warnings, [])
+        self.assertEqual(len(self.scheduler.queued), 1)
+        self.scheduler.queued[0]()
+        self.evaluator._Evaluator__trigger_callbacks.assert_not_called()
+        self.assertEqual(self.evaluator._Evaluator__condition_state_change_delayed_cb_handle,
+                         current)
+        self.assertEqual(len(self.evaluator._Evaluator__condition_state_change_delayed), 2)
+        self.scheduler.expire(current)()
+        self.evaluator._Evaluator__trigger_callbacks.assert_called_once()
+        self.evaluator._Evaluator__log.assert_not_called()
+
+    def test_zero_delay_remains_immediate(self):
+        self.evaluator._Evaluator__callback_delay = 0
+        self.change('20', '21')
+        self.evaluator._Evaluator__trigger_callbacks.assert_called_once()
+        self.assertEqual(self.scheduler.timers, {})
+
+
+if __name__ == '__main__':
+    unittest.main()

virtualsensors.py

@@ -757,20 +757,28 @@ class EventSensor(VirtualSensorBase):
 
         self.retain_time = self.yaml_block['retain_time']
         self.cb_handle = None
+        self._timer_generation = 0
 
         self.event_handlers = []
         if "activation_events" in self.yaml_block:
             self.event_handlers.append(EventHandler(self.ad_api, self.yaml_block["activation_events"], self.on_activation_event,logger_interface = self.logger_interface))
         
     def on_activation_event(self, event_name, data, kwargs):
+        self._timer_generation += 1
         self.output_sensor.set_state(state = 'on')
         if self.cb_handle is not None:
-            self.ad_api.cancel_timer(self.cb_handle)
-        self.cb_handle = self.ad_api.run_in(self.on_retain_time_elapsed, self.retain_time)
+            self.ad_api.cancel_timer(self.cb_handle, silent=True)
+        self.cb_handle = self.ad_api.run_in(
+            self.on_retain_time_elapsed, self.retain_time,
+            generation=self._timer_generation,
+        )
 
     def on_retain_time_elapsed(self, kwargs):
-        self.output_sensor.set_state(state = 'off')
+        # Cancellation cannot retract a callback already queued by AppDaemon.
+        if kwargs.get('generation') != self._timer_generation:
+            return
         self.cb_handle = None
+        self.output_sensor.set_state(state = 'off')
 
     def generate_sensor_name(self,virtual_sensor_name):
         return f"binary_sensor.{virtual_sensor_name}"