Switch underlying history stats calculation to use seconds (#77857)

* Switch history stats to report in seconds

Because hours were previously used, the data would always be off because
of the loss of resolution when the time being tracked was in a window
of more than 12s

* Apply suggestions from code review

* Update homeassistant/components/history_stats/sensor.py

* tweak

homeassistant/components/history_stats/data.py

@@ -18,7 +18,7 @@ MIN_TIME_UTC = datetime.datetime.min.replace(tzinfo=dt_util.UTC)
 class HistoryStatsState:
     """The current stats of the history stats."""
 
-    hours_matched: float | None
+    seconds_matched: float | None
     match_count: int | None
     period: tuple[datetime.datetime, datetime.datetime]
 
@@ -125,12 +125,12 @@ class HistoryStats:
             await self._async_history_from_db(current_period_start, current_period_end)
             self._previous_run_before_start = False
 
-        hours_matched, match_count = self._async_compute_hours_and_changes(
+        seconds_matched, match_count = self._async_compute_seconds_and_changes(
             now_timestamp,
             current_period_start_timestamp,
             current_period_end_timestamp,
         )
-        self._state = HistoryStatsState(hours_matched, match_count, self._period)
+        self._state = HistoryStatsState(seconds_matched, match_count, self._period)
         return self._state
 
     async def _async_history_from_db(
@@ -162,10 +162,10 @@ class HistoryStats:
             no_attributes=True,
         ).get(self.entity_id, [])
 
-    def _async_compute_hours_and_changes(
+    def _async_compute_seconds_and_changes(
         self, now_timestamp: float, start_timestamp: float, end_timestamp: float
     ) -> tuple[float, int]:
-        """Compute the hours matched and changes from the history list and first state."""
+        """Compute the seconds matched and changes from the history list and first state."""
         # state_changes_during_period is called with include_start_time_state=True
         # which is the default and always provides the state at the start
         # of the period
@@ -195,6 +195,6 @@ class HistoryStats:
             measure_end = min(end_timestamp, now_timestamp)
             elapsed += measure_end - last_state_change_timestamp
 
-        # Save value in hours
-        hours_matched = elapsed / 3600
-        return hours_matched, match_count
+        # Save value in seconds
+        seconds_matched = elapsed
+        return seconds_matched, match_count

homeassistant/components/history_stats/helpers.py

@@ -79,7 +79,7 @@ def pretty_ratio(
     if len(period) != 2 or period[0] == period[1]:
         return 0.0
 
-    ratio = 100 * 3600 * value / (period[1] - period[0]).total_seconds()
+    ratio = 100 * value / (period[1] - period[0]).total_seconds()
     return round(ratio, 1)
 
 

homeassistant/components/history_stats/sensor.py

@@ -163,13 +163,13 @@ class HistoryStatsSensor(HistoryStatsSensorBase):
     def _process_update(self) -> None:
         """Process an update from the coordinator."""
         state = self.coordinator.data
-        if state is None or state.hours_matched is None:
+        if state is None or state.seconds_matched is None:
             self._attr_native_value = None
             return
 
         if self._type == CONF_TYPE_TIME:
-            self._attr_native_value = round(state.hours_matched, 2)
+            self._attr_native_value = round(state.seconds_matched / 3600, 2)
         elif self._type == CONF_TYPE_RATIO:
-            self._attr_native_value = pretty_ratio(state.hours_matched, state.period)
+            self._attr_native_value = pretty_ratio(state.seconds_matched, state.period)
         elif self._type == CONF_TYPE_COUNT:
             self._attr_native_value = state.match_count