Partial revert of update to remote calendar to fix issue where calendar does not update (home-assistant#146702)

Partial revert

Author: allenporter

homeassistant/components/remote_calendar/calendar.py

@@ -4,6 +4,7 @@
 import logging
 
 from ical.event import Event
+from ical.timeline import Timeline
 
 from homeassistant.components.calendar import CalendarEntity, CalendarEvent
 from homeassistant.core import HomeAssistant
@@ -48,12 +49,18 @@ def __init__(
         super().__init__(coordinator)
         self._attr_name = entry.data[CONF_CALENDAR_NAME]
         self._attr_unique_id = entry.entry_id
-        self._event: CalendarEvent | None = None
+        self._timeline: Timeline | None = None
 
     @property
     def event(self) -> CalendarEvent | None:
         """Return the next upcoming event."""
-        return self._event
+        if self._timeline is None:
+            return None
+        now = dt_util.now()
+        events = self._timeline.active_after(now)
+        if event := next(events, None):
+            return _get_calendar_event(event)
+        return None
 
     async def async_get_events(
         self, hass: HomeAssistant, start_date: datetime, end_date: datetime
@@ -79,15 +86,12 @@ async def async_update(self) -> None:
         """
         await super().async_update()
 
-        def next_timeline_event() -> CalendarEvent | None:
+        def _get_timeline() -> Timeline | None:
             """Return the next active event."""
             now = dt_util.now()
-            events = self.coordinator.data.timeline_tz(now.tzinfo).active_after(now)
-            if event := next(events, None):
-                return _get_calendar_event(event)
-            return None
+            return self.coordinator.data.timeline_tz(now.tzinfo)
 
-        self._event = await self.hass.async_add_executor_job(next_timeline_event)
+        self._timeline = await self.hass.async_add_executor_job(_get_timeline)
 
 
 def _get_calendar_event(event: Event) -> CalendarEvent: