Fix MQTT Light with RGB and Brightness (#15053)

* Fix MQTT Light with RGB and Brightness

When an MQTT light is given an RGB and Brightness topic, the RGB
is scaled by the brightness *as well* as the brightness being set

This causes 255,0,0 at 50% brightness to be sent as 127,0,0 at 50%
brightness, which ends up as 63,0,0 after the RGB bulb has applied
its brightness scaling.

Fixes the same issue in mqtt, mqtt-json and mqtt-template.

Related Issue: #13725

* Add comment to mqtt_json as well

homeassistant/components/light/mqtt.py

@@ -442,8 +442,15 @@ class MqttLight(MqttAvailability, Light):
            self._topic[CONF_RGB_COMMAND_TOPIC] is not None:
 
             hs_color = kwargs[ATTR_HS_COLOR]
-            brightness = kwargs.get(
+
-                ATTR_BRIGHTNESS, self._brightness if self._brightness else 255)
+            # If there's a brightness topic set, we don't want to scale the RGB
+            # values given using the brightness.
+            if self._topic[CONF_BRIGHTNESS_COMMAND_TOPIC] is not None:
+                brightness = 255
+            else:
+                brightness = kwargs.get(
+                    ATTR_BRIGHTNESS, self._brightness if self._brightness else
+                    255)
             rgb = color_util.color_hsv_to_RGB(
                 hs_color[0], hs_color[1], brightness / 255 * 100)
             tpl = self._templates[CONF_RGB_COMMAND_TEMPLATE]

homeassistant/components/light/mqtt_json.py

@@ -345,9 +345,14 @@ class MqttJson(MqttAvailability, Light):
             hs_color = kwargs[ATTR_HS_COLOR]
             message['color'] = {}
             if self._rgb:
-                brightness = kwargs.get(
+                # If there's a brightness topic set, we don't want to scale the
-                    ATTR_BRIGHTNESS,
+                # RGB values given using the brightness.
-                    self._brightness if self._brightness else 255)
+                if self._brightness is not None:
+                    brightness = 255
+                else:
+                    brightness = kwargs.get(
+                        ATTR_BRIGHTNESS,
+                        self._brightness if self._brightness else 255)
                 rgb = color_util.color_hsv_to_RGB(
                     hs_color[0], hs_color[1], brightness / 255 * 100)
                 message['color']['r'] = rgb[0]

homeassistant/components/light/mqtt_template.py

@@ -317,8 +317,15 @@ class MqttTemplate(MqttAvailability, Light):
 
         if ATTR_HS_COLOR in kwargs:
             hs_color = kwargs[ATTR_HS_COLOR]
-            brightness = kwargs.get(
+
-                ATTR_BRIGHTNESS, self._brightness if self._brightness else 255)
+            # If there's a brightness topic set, we don't want to scale the RGB
+            # values given using the brightness.
+            if self._templates[CONF_BRIGHTNESS_TEMPLATE] is not None:
+                brightness = 255
+            else:
+                brightness = kwargs.get(
+                    ATTR_BRIGHTNESS, self._brightness if self._brightness else
+                    255)
             rgb = color_util.color_hsv_to_RGB(
                 hs_color[0], hs_color[1], brightness / 255 * 100)
             values['red'] = rgb[0]

tests/components/light/test_mqtt.py

@@ -523,24 +523,24 @@ class TestLightMQTT(unittest.TestCase):
         self.mock_publish.reset_mock()
         light.turn_on(self.hass, 'light.test',
                       brightness=50, xy_color=[0.123, 0.123])
-        light.turn_on(self.hass, 'light.test', rgb_color=[75, 75, 75],
+        light.turn_on(self.hass, 'light.test', rgb_color=[255, 128, 0],
                       white_value=80)
         self.hass.block_till_done()
 
         self.mock_publish.async_publish.assert_has_calls([
             mock.call('test_light_rgb/set', 'on', 2, False),
-            mock.call('test_light_rgb/rgb/set', '50,50,50', 2, False),
+            mock.call('test_light_rgb/rgb/set', '255,128,0', 2, False),
             mock.call('test_light_rgb/brightness/set', 50, 2, False),
             mock.call('test_light_rgb/white_value/set', 80, 2, False),
-            mock.call('test_light_rgb/xy/set', '0.323,0.329', 2, False),
+            mock.call('test_light_rgb/xy/set', '0.14,0.131', 2, False),
         ], any_order=True)
 
         state = self.hass.states.get('light.test')
         self.assertEqual(STATE_ON, state.state)
-        self.assertEqual((255, 255, 255), state.attributes['rgb_color'])
+        self.assertEqual((255, 128, 0), state.attributes['rgb_color'])
         self.assertEqual(50, state.attributes['brightness'])
         self.assertEqual(80, state.attributes['white_value'])
-        self.assertEqual((0.323, 0.329), state.attributes['xy_color'])
+        self.assertEqual((0.611, 0.375), state.attributes['xy_color'])
 
     def test_sending_mqtt_rgb_command_with_template(self):
         """Test the sending of RGB command with template."""
@@ -808,11 +808,11 @@ class TestLightMQTT(unittest.TestCase):
 
         # Turn on w/ just a color to insure brightness gets
         # added and sent.
-        light.turn_on(self.hass, 'light.test', rgb_color=[75, 75, 75])
+        light.turn_on(self.hass, 'light.test', rgb_color=[255, 128, 0])
         self.hass.block_till_done()
 
         self.mock_publish.async_publish.assert_has_calls([
-            mock.call('test_light/rgb', '50,50,50', 0, False),
+            mock.call('test_light/rgb', '255,128,0', 0, False),
             mock.call('test_light/bright', 50, 0, False)
         ], any_order=True)
 

tests/components/light/test_mqtt_json.py

@@ -381,8 +381,8 @@ class TestLightMQTTJSON(unittest.TestCase):
         self.assertEqual(50, message_json["brightness"])
         self.assertEqual({
             'r': 0,
-            'g': 50,
+            'g': 255,
-            'b': 4,
+            'b': 21,
         }, message_json["color"])
         self.assertEqual("ON", message_json["state"])