Fix trigger condition and alarm message in Tuya Alarm (#132963)

Co-authored-by: Franck Nijhof <git@frenck.dev>

homeassistant/components/tuya/alarm_control_panel.py

@@ -2,6 +2,8 @@
 
 from __future__ import annotations
 
+from base64 import b64decode
+from dataclasses import dataclass
 from enum import StrEnum
 
 from tuya_sharing import CustomerDevice, Manager
@@ -18,7 +20,15 @@ from homeassistant.helpers.entity_platform import AddConfigEntryEntitiesCallback
 
 from . import TuyaConfigEntry
 from .const import TUYA_DISCOVERY_NEW, DPCode, DPType
-from .entity import TuyaEntity
+from .entity import EnumTypeData, TuyaEntity
+
+
+@dataclass(frozen=True)
+class TuyaAlarmControlPanelEntityDescription(AlarmControlPanelEntityDescription):
+    """Describe a Tuya Alarm Control Panel entity."""
+
+    master_state: DPCode | None = None
+    alarm_msg: DPCode | None = None
 
 
 class Mode(StrEnum):
@@ -30,6 +40,13 @@ class Mode(StrEnum):
     SOS = "sos"
 
 
+class State(StrEnum):
+    """Alarm states."""
+
+    NORMAL = "normal"
+    ALARM = "alarm"
+
+
 STATE_MAPPING: dict[str, AlarmControlPanelState] = {
     Mode.DISARMED: AlarmControlPanelState.DISARMED,
     Mode.ARM: AlarmControlPanelState.ARMED_AWAY,
@@ -40,12 +57,14 @@ STATE_MAPPING: dict[str, AlarmControlPanelState] = {
 
 # All descriptions can be found here:
 # https://developer.tuya.com/en/docs/iot/standarddescription?id=K9i5ql6waswzq
-ALARM: dict[str, tuple[AlarmControlPanelEntityDescription, ...]] = {
+ALARM: dict[str, tuple[TuyaAlarmControlPanelEntityDescription, ...]] = {
     # Alarm Host
     # https://developer.tuya.com/en/docs/iot/categorymal?id=Kaiuz33clqxaf
     "mal": (
-        AlarmControlPanelEntityDescription(
+        TuyaAlarmControlPanelEntityDescription(
             key=DPCode.MASTER_MODE,
+            master_state=DPCode.MASTER_STATE,
+            alarm_msg=DPCode.ALARM_MSG,
             name="Alarm",
         ),
     )
@@ -86,12 +105,14 @@ class TuyaAlarmEntity(TuyaEntity, AlarmControlPanelEntity):
 
     _attr_name = None
     _attr_code_arm_required = False
+    _master_state: EnumTypeData | None = None
+    _alarm_msg_dpcode: DPCode | None = None
 
     def __init__(
         self,
         device: CustomerDevice,
         device_manager: Manager,
-        description: AlarmControlPanelEntityDescription,
+        description: TuyaAlarmControlPanelEntityDescription,
     ) -> None:
         """Init Tuya Alarm."""
         super().__init__(device, device_manager)
@@ -111,13 +132,39 @@ class TuyaAlarmEntity(TuyaEntity, AlarmControlPanelEntity):
             if Mode.SOS in supported_modes.range:
                 self._attr_supported_features |= AlarmControlPanelEntityFeature.TRIGGER
 
+        # Determine master state
+        if enum_type := self.find_dpcode(
+            description.master_state, dptype=DPType.ENUM, prefer_function=True
+        ):
+            self._master_state = enum_type
+
+        # Determine alarm message
+        if dp_code := self.find_dpcode(description.alarm_msg, prefer_function=True):
+            self._alarm_msg_dpcode = dp_code
+
     @property
     def alarm_state(self) -> AlarmControlPanelState | None:
         """Return the state of the device."""
+        # When the alarm is triggered, only its 'state' is changing. From 'normal' to 'alarm'.
+        # The 'mode' doesn't change, and stays as 'arm' or 'home'.
+        if self._master_state is not None:
+            if self.device.status.get(self._master_state.dpcode) == State.ALARM:
+                return AlarmControlPanelState.TRIGGERED
+
         if not (status := self.device.status.get(self.entity_description.key)):
             return None
         return STATE_MAPPING.get(status)
 
+    @property
+    def changed_by(self) -> str | None:
+        """Last change triggered by."""
+        if self._master_state is not None and self._alarm_msg_dpcode is not None:
+            if self.device.status.get(self._master_state.dpcode) == State.ALARM:
+                encoded_msg = self.device.status.get(self._alarm_msg_dpcode)
+                if encoded_msg:
+                    return b64decode(encoded_msg).decode("utf-16be")
+        return None
+
     def alarm_disarm(self, code: str | None = None) -> None:
         """Send Disarm command."""
         self._send_command(

homeassistant/components/tuya/const.py

@@ -102,6 +102,7 @@ class DPCode(StrEnum):
     ALARM_TIME = "alarm_time"  # Alarm time
     ALARM_VOLUME = "alarm_volume"  # Alarm volume
     ALARM_MESSAGE = "alarm_message"
+    ALARM_MSG = "alarm_msg"
     ANGLE_HORIZONTAL = "angle_horizontal"
     ANGLE_VERTICAL = "angle_vertical"
     ANION = "anion"  # Ionizer unit
@@ -226,6 +227,7 @@ class DPCode(StrEnum):
     LIGHT_MODE = "light_mode"
     LOCK = "lock"  # Lock / Child lock
     MASTER_MODE = "master_mode"  # alarm mode
+    MASTER_STATE = "master_state"  # alarm state
     MACH_OPERATE = "mach_operate"
     MANUAL_FEED = "manual_feed"
     MATERIAL = "material"  # Material