Expose error states

[mikelward]

T-Smart exposes warnings and errors.

I'd love to get notified when there is an error so I can go check, and switch over my to boiler. (Right now, I'm using it being in heat mode and the temperature not going up, but I think it would be nice to know exactly when the error happened.)

Don't have access to my laptop right now, but from what I can see, creating binary sensors for warning and error might be a simple approach?

class TSmartErrorEntity(TSmartCoordinatorEntity, BinarySensorEntity):
    _attr_device_class = BinarySensorDeviceClass.PROBLEM

    # Inherit name from DeviceInfo, which is obtained from actual device
    _attr_has_entity_name = True
    _attr_name = "Error"

    @property
    def is_on(self):
        return self._tsmart.mode == self._tsmart.mode.CRITICAL

class TSmartWarningEntity(TSmartCoordinatorEntity, BinarySensorEntity):
    _attr_device_class = BinarySensorDeviceClass.PROBLEM

    # Inherit name from DeviceInfo, which is obtained from actual device
    _attr_has_entity_name = True
    _attr_name = "Warning"

    @property
    def is_on(self):
        return self._tsmart.mode == self._tsmart.mode.LIMITED

Happy to send a pull request later if you like.

Eventually I'd also like to know which error code it is, e.g. E03, but the above would be sufficient.

Thanks!