🐛 Allow to power off DHW

Before this patch, trying to stop DHW when zone heating was also stopped
failed. This comes from the impossibility to disable every feature (zone
heating and DHW) at the same time: there is no OperatingMode
corresponding to this state.

We fix this in this patch by reusing the same logic than Zone climate
entities: we can reach the target state by controlling another setting.
In this case: the heatpump entire state.

Need to disable DHW seems a rare use case to me (if one uses holidays
mode) but at least we now have a consistent behavior.

Fixes #30

Change-Id: I29ea322ee258e8f7f8d6656d8835a09675605141

custom_components/aquarea/climate.py

@@ -118,6 +118,8 @@ def __init__(
         self._attr_preset_modes = [PRESET_ECO, PRESET_COMFORT]
         self._attr_preset_mode = PRESET_ECO
 
+        self._heatpump_state = False
+
     async def async_set_temperature(self, **kwargs) -> None:
         temperature = kwargs.get("temperature")
         _LOGGER.debug(f"Changing {self.name} target temperature to {temperature})")
@@ -170,13 +172,29 @@ def target_temperature_message_received(message):
             1,
         )
 
+        def guess_hvac_mode() -> HVACMode:
+            if OperatingMode.DHW in self._operating_mode and self._heatpump_state:
+                return HVACMode.HEAT
+            else:
+                return HVACMode.OFF
+
+        @callback
+        def heatpump_state_message_received(message):
+            self._heatpump_state = bool(int(message.payload))
+            self._attr_hvac_mode = guess_hvac_mode()
+            self.async_write_ha_state()
+
+        await mqtt.async_subscribe(
+            self.hass,
+            "panasonic_heat_pump/main/Heatpump_State",
+            heatpump_state_message_received,
+            1,
+        )
+
         @callback
         def operating_state_message_received(message):
             self._operating_mode = OperatingMode.from_mqtt(message.payload)
-            if OperatingMode.DHW in self._operating_mode:
-                self._attr_hvac_mode = HVACMode.HEAT
-            else:
-                self._attr_hvac_mode = HVACMode.OFF
+            self._attr_hvac_mode = guess_hvac_mode()
             self.async_write_ha_state()
 
         await mqtt.async_subscribe(
@@ -187,29 +205,39 @@ def operating_state_message_received(message):
         )
 
     async def async_set_hvac_mode(self, hvac_mode: HVACMode) -> None:
+        new_heatpump_state = self._heatpump_state
         if hvac_mode == HVACMode.HEAT:
-            value = self._operating_mode | OperatingMode.DHW
+            new_operating_mode = self._operating_mode | OperatingMode.DHW
+            new_heatpump_state = True
         elif hvac_mode == HVACMode.OFF:
-            value = self._operating_mode & ~OperatingMode.DHW
-            if value == OperatingMode(0):  # i.e "none"
-                _LOGGER.warn(
-                    f"Impossible to set {hvac_mode} on this heatpump, we can't disable water heater when heating/cooling is already disabled"
-                )
-                raise NotImplemented(
-                    f"Powering off heatpump entirely has not been implemented by this entity"
-                )
+            new_operating_mode = self._operating_mode & ~OperatingMode.DHW
+            if new_operating_mode == OperatingMode(0):  # i.e "none"
+                new_heatpump_state = False
         else:
             raise NotImplemented(
                 f"Mode {hvac_mode} has not been implemented by this entity"
             )
-        await async_publish(
-            self.hass,
-            "panasonic_heat_pump/commands/SetOperationMode",
-            value.to_mqtt(),
-            0,
-            False,
-            "utf-8",
-        )
+        if (
+            new_operating_mode != OperatingMode(0)
+            and new_operating_mode != self._operating_mode
+        ):
+            await async_publish(
+                self.hass,
+                "panasonic_heat_pump/commands/SetOperationMode",
+                new_operating_mode.to_mqtt(),
+                0,
+                False,
+                "utf-8",
+            )
+        if new_heatpump_state != self._heatpump_state:
+            await async_publish(
+                self.hass,
+                "panasonic_heat_pump/commands/SetHeatpump",
+                str(int(new_heatpump_state)),
+                0,
+                False,
+                "utf-8",
+            )
         self._attr_hvac_mode = hvac_mode  # let's be optimistic
         self.async_write_ha_state()