Fix bug in google calendar offset calculation (#70024)

Move the offset reached computation outside of the update method so that it is
computed when state updates occur rather than when data refreshes happen (which
are throttled and happen at most every 15 minutes).

Issue #69892

homeassistant/components/google/calendar.py

@@ -120,13 +120,22 @@ class GoogleCalendarEntity(CalendarEntity):
         self._event: CalendarEvent | None = None
         self._name: str = data[CONF_NAME]
         self._offset = data.get(CONF_OFFSET, DEFAULT_CONF_OFFSET)
-        self._offset_reached = False
+        self._offset_value: timedelta | None = None
         self.entity_id = entity_id
 
     @property
     def extra_state_attributes(self) -> dict[str, bool]:
         """Return the device state attributes."""
-        return {"offset_reached": self._offset_reached}
+        return {"offset_reached": self.offset_reached}
+
+    @property
+    def offset_reached(self) -> bool:
+        """Return whether or not the event offset was reached."""
+        if self._event and self._offset_value:
+            return is_offset_reached(
+                self._event.start_datetime_local, self._offset_value
+            )
+        return False
 
     @property
     def event(self) -> CalendarEvent | None:
@@ -187,9 +196,7 @@ class GoogleCalendarEntity(CalendarEntity):
             (summary, offset) = extract_offset(event.get("summary", ""), self._offset)
             event["summary"] = summary
             self._event = _get_calendar_event(event)
-            self._offset_reached = is_offset_reached(
-                self._event.start_datetime_local, offset
-            )
+            self._offset_value = offset
         else:
             self._event = None
 

tests/components/google/test_calendar.py

@@ -505,3 +505,77 @@ async def test_scan_calendar_error(
         assert await component_setup()
 
     assert not hass.states.get(TEST_ENTITY)
+
+
+async def test_future_event_update_behavior(
+    hass, mock_events_list_items, component_setup
+):
+    """Test an future event that becomes active."""
+    now = dt_util.now()
+    now_utc = dt_util.utcnow()
+    one_hour_from_now = now + datetime.timedelta(minutes=60)
+    end_event = one_hour_from_now + datetime.timedelta(minutes=90)
+    event = {
+        **TEST_EVENT,
+        "start": {"dateTime": one_hour_from_now.isoformat()},
+        "end": {"dateTime": end_event.isoformat()},
+    }
+    mock_events_list_items([event])
+    assert await component_setup()
+
+    # Event has not started yet
+    state = hass.states.get(TEST_ENTITY)
+    assert state.name == TEST_ENTITY_NAME
+    assert state.state == STATE_OFF
+
+    # Advance time until event has started
+    now += datetime.timedelta(minutes=60)
+    now_utc += datetime.timedelta(minutes=30)
+    with patch("homeassistant.util.dt.utcnow", return_value=now_utc), patch(
+        "homeassistant.util.dt.now", return_value=now
+    ):
+        async_fire_time_changed(hass, now)
+        await hass.async_block_till_done()
+
+    # Event has started
+    state = hass.states.get(TEST_ENTITY)
+    assert state.state == STATE_ON
+
+
+async def test_future_event_offset_update_behavior(
+    hass, mock_events_list_items, component_setup
+):
+    """Test an future event that becomes active."""
+    now = dt_util.now()
+    now_utc = dt_util.utcnow()
+    one_hour_from_now = now + datetime.timedelta(minutes=60)
+    end_event = one_hour_from_now + datetime.timedelta(minutes=90)
+    event_summary = "Test Event in Progress"
+    event = {
+        **TEST_EVENT,
+        "start": {"dateTime": one_hour_from_now.isoformat()},
+        "end": {"dateTime": end_event.isoformat()},
+        "summary": f"{event_summary} !!-15",
+    }
+    mock_events_list_items([event])
+    assert await component_setup()
+
+    # Event has not started yet
+    state = hass.states.get(TEST_ENTITY)
+    assert state.name == TEST_ENTITY_NAME
+    assert state.state == STATE_OFF
+    assert not state.attributes["offset_reached"]
+
+    # Advance time until event has started
+    now += datetime.timedelta(minutes=45)
+    now_utc += datetime.timedelta(minutes=45)
+    with patch("homeassistant.util.dt.utcnow", return_value=now_utc), patch(
+        "homeassistant.util.dt.now", return_value=now
+    ):
+        async_fire_time_changed(hass, now)
+        await hass.async_block_till_done()
+
+    # Event has not started, but the offset was reached
+    state = hass.states.get(TEST_ENTITY)
+    assert state.state == STATE_OFF
+    assert state.attributes["offset_reached"]