Add an additional last updated diagnostic sensor for devices

custom_components/oasis_mini/pyoasiscontrol/device.py

@@ -3,6 +3,7 @@
 from __future__ import annotations
 
 import asyncio
+from datetime import datetime
 import logging
 from typing import TYPE_CHECKING, Any, Callable, Final, Iterable
 
@@ -21,6 +22,7 @@ from .utils import (
     create_svg,
     decrypt_svg_content,
     get_image_url_from_track,
+    now,
 )
 
 if TYPE_CHECKING:  # avoid runtime circular imports
@@ -140,6 +142,9 @@ class OasisDevice:
         self._track: dict | None = None
         self._track_task: asyncio.Task | None = None
 
+        # Diagnostic metadata
+        self.last_updated: datetime | None = None
+
     @property
     def brightness(self) -> int:
         """
@@ -259,6 +264,8 @@ class OasisDevice:
         if changed:
             self._notify_listeners()
 
+        self.last_updated = now()
+
     def parse_status_string(self, raw_status: str) -> dict[str, Any] | None:
         """
         Parse a semicolon-separated device status string into a structured state dictionary.

custom_components/oasis_mini/sensor.py

@@ -2,7 +2,10 @@
 
 from __future__ import annotations
 
+from datetime import datetime
+
 from homeassistant.components.sensor import (
+    SensorDeviceClass,
     SensorEntity,
     SensorEntityDescription,
     SensorStateClass,
@@ -68,6 +71,13 @@ DESCRIPTORS = [
         state_class=SensorStateClass.MEASUREMENT,
         suggested_display_precision=1,
     ),
+    SensorEntityDescription(
+        key="last_updated",
+        translation_key="last_updated",
+        device_class=SensorDeviceClass.TIMESTAMP,
+        entity_category=EntityCategory.DIAGNOSTIC,
+        entity_registry_enabled_default=False,
+    ),
 ]
 DESCRIPTORS.extend(
     SensorEntityDescription(
@@ -84,7 +94,7 @@ class OasisDeviceSensorEntity(OasisDeviceEntity, SensorEntity):
     """Oasis device sensor entity."""
 
     @property
-    def native_value(self) -> str | None:
+    def native_value(self) -> str | int | float | datetime | None:
         """
         Provide the current sensor value from the underlying device.
 

custom_components/oasis_mini/strings.json

@@ -125,6 +125,9 @@
           "18": "Error while downloading the job file"
         }
       },
+      "last_updated": {
+        "name": "Last updated"
+      },
       "led_color_id": {
         "name": "LED color ID"
       },

custom_components/oasis_mini/translations/en.json

@@ -125,6 +125,9 @@
           "18": "Error while downloading the job file"
         }
       },
+      "last_updated": {
+        "name": "Last updated"
+      },
       "led_color_id": {
         "name": "LED color ID"
       },