From ffb8872f959d4e9b935c3dcded7b33dbd99b7d4f Mon Sep 17 00:00:00 2001
From: Anders Melchiorsen <amelchio@nogoto.net>
Date: Wed, 26 Apr 2017 17:21:14 +0200
Subject: [PATCH] LIFX: use white light when setting a specific temperature
 (#7256)

* Default to white when setting LIFX temperature

Changing the temperature of a saturated color is possible but not very
interesting. So assume that a change of the temperature implies setting
the color to white, unless a different color is actually specified.

This makes the frontend temperature picker much more useful because it can
now be used to get away from a colored light.

* Default to a neutral white temperature when setting LIFX colors

This means that setting a particular color will always give the same output,
no matter what the temperature was previously at.

* Find brightness after colors

Now the color_temp logic will not see a changed color when setting
temperature+brightness and thus we will actually get a white light in
this situation.

The XY conversion can then not use brightness as input. This is not
an issue because XY only affects hue and saturation, not brightness. So
we can just use an arbitrary value as brightness input.

* Add a simple comment to a complex conditional
---
 .../components/light/lifx/__init__.py         | 36 +++++++++++--------
 1 file changed, 21 insertions(+), 15 deletions(-)

diff --git a/homeassistant/components/light/lifx/__init__.py b/homeassistant/components/light/lifx/__init__.py
index 552e1d8f77f..c43b901e910 100644
--- a/homeassistant/components/light/lifx/__init__.py
+++ b/homeassistant/components/light/lifx/__init__.py
@@ -353,27 +353,33 @@ class LIFXLight(Light):
             saturation = self._sat
             brightness = self._bri
 
+        if ATTR_XY_COLOR in kwargs:
+            hue, saturation, _ = \
+                color_util.color_xy_brightness_to_hsv(
+                    *kwargs[ATTR_XY_COLOR],
+                    ibrightness=255)
+            saturation = saturation * (BYTE_MAX + 1)
+            changed_color = True
+
+        # When color or temperature is set, use a default value for the other
+        if ATTR_COLOR_TEMP in kwargs:
+            kelvin = int(color_temperature_mired_to_kelvin(
+                kwargs[ATTR_COLOR_TEMP]))
+            if not changed_color:
+                saturation = 0
+            changed_color = True
+        else:
+            if changed_color:
+                kelvin = 3500
+            else:
+                kelvin = self._kel
+
         if ATTR_BRIGHTNESS in kwargs:
             brightness = kwargs[ATTR_BRIGHTNESS] * (BYTE_MAX + 1)
             changed_color = True
         else:
             brightness = self._bri
 
-        if ATTR_XY_COLOR in kwargs:
-            hue, saturation, _ = \
-                color_util.color_xy_brightness_to_hsv(
-                    *kwargs[ATTR_XY_COLOR],
-                    ibrightness=(brightness // (BYTE_MAX + 1)))
-            saturation = saturation * (BYTE_MAX + 1)
-            changed_color = True
-
-        if ATTR_COLOR_TEMP in kwargs:
-            kelvin = int(color_temperature_mired_to_kelvin(
-                kwargs[ATTR_COLOR_TEMP]))
-            changed_color = True
-        else:
-            kelvin = self._kel
-
         return [[hue, saturation, brightness, kelvin], changed_color]
 
     def set_power(self, power):