Make iot time timezone aware (#1147)

Also makes on_since for iot devices use device time.
Changes the return value for device.timezone to be tzinfo instead of a dict.

kasa/iot/modules/emeter.py

@@ -12,7 +12,7 @@ from .usage import Usage
 class Emeter(Usage, EnergyInterface):
     """Emeter module."""
 
-    def _post_update_hook(self) -> None:
+    async def _post_update_hook(self) -> None:
         self._supported = EnergyInterface.ModuleFeature.PERIODIC_STATS
         if (
             "voltage_mv" in self.data["get_realtime"]

kasa/iot/modules/light.py

@@ -239,7 +239,7 @@ class Light(IotModule, LightInterface):
         """Return the current light state."""
         return self._light_state
 
-    def _post_update_hook(self) -> None:
+    async def _post_update_hook(self) -> None:
         if self._device.is_on is False:
             state = LightState(light_on=False)
         else:

kasa/iot/modules/lightpreset.py

@@ -41,7 +41,7 @@ class LightPreset(IotModule, LightPresetInterface):
     _presets: dict[str, IotLightPreset]
     _preset_list: list[str]
 
-    def _post_update_hook(self):
+    async def _post_update_hook(self):
         """Update the internal presets."""
         self._presets = {
             f"Light preset {index+1}": IotLightPreset(**vals)

kasa/iot/modules/time.py

@@ -1,14 +1,19 @@
 """Provides the current time and timezone information."""
 
-from datetime import datetime
+from __future__ import annotations
+
+from datetime import datetime, timezone, tzinfo
 
 from ...exceptions import KasaException
 from ..iotmodule import IotModule, merge
+from ..iottimezone import get_timezone
 
 
 class Time(IotModule):
     """Implements the timezone settings."""
 
+    _timezone: tzinfo = timezone.utc
+
     def query(self):
         """Request time and timezone."""
         q = self.query_for_command("get_time")
@@ -16,11 +21,16 @@ class Time(IotModule):
         merge(q, self.query_for_command("get_timezone"))
         return q
 
+    async def _post_update_hook(self):
+        """Perform actions after a device update."""
+        if res := self.data.get("get_timezone"):
+            self._timezone = await get_timezone(res.get("index"))
+
     @property
     def time(self) -> datetime:
         """Return current device time."""
         res = self.data["get_time"]
-        return datetime(
+        time = datetime(
             res["year"],
             res["month"],
             res["mday"],
@@ -28,12 +38,12 @@ class Time(IotModule):
             res["min"],
             res["sec"],
         )
+        return time.astimezone(self.timezone)
 
     @property
-    def timezone(self):
+    def timezone(self) -> tzinfo:
         """Return current timezone."""
-        res = self.data["get_timezone"]
-        return res
+        return self._timezone
 
     async def get_time(self):
         """Return current device time."""