[shelly] Fix Pro RGBWW PM colorFull White option turning the light off

The rgb:0 component has no white parameter, so selecting "white" on the
colorFull channel sent rgb=0,0,0 with a dropped white value, switching
the light off instead of producing white. Mix full RGB (255,255,255)
instead for this component, and recognize that combination when
reporting the current colorFull state back.

Signed-off-by: Markus Michels <markus7017@gmail.com>

Author: markus7017

bundles/org.openhab.binding.shelly/README.md

@@ -1755,8 +1755,9 @@ In `rgbcct` or `rgbx2light` profile, the RGB component is exposed as the color c
 |         | autoOff       | Number   | r/w       | Sets a  timer to turn the device OFF after every ON command; in seconds |
 |         | timerActive   | Switch   | yes       | ON: An auto-on/off timer is active                                      |
 | color   | hsb           | HSB      | r/w       | Represents the color picker (HSBType)                                   |
-|         | full          | String   | r/w       | Set Red / Green / Blue / Yellow mode and switch mode                    |
-|         |               |          | r/w       | Valid settings: "red", "green", "blue", "yellow" or "r,g,b"             |
+|         | full          | String   | r/w       | Set Red / Green / Blue / Yellow / White mode and switch mode            |
+|         |               |          | r/w       | Valid settings: "red", "green", "blue", "yellow", "white" or "r,g,b"    |
+|         |               |          | r/w       | "white" sets RGB to 255,255,255 (no separate white output)              |
 |         | red           | Dimmer   | r/w       | Red brightness: 0..100% (control only the red channel)                  |
 |         | green         | Dimmer   | r/w       | Green brightness: 0..100% (control only the green channel)              |
 |         | blue          | Dimmer   | r/w       | Blue brightness: 0..100% (control only the blue channel)                |

bundles/org.openhab.binding.shelly/src/main/java/org/openhab/binding/shelly/internal/handler/ShellyLightHandler.java

@@ -304,7 +304,11 @@ private boolean handleFullColor(ShellyColorUtils col, Command command) throws Il
         } else if (color.equals(SHELLY_COLOR_YELLOW)) {
             col.setRGBW(SHELLY_MAX_COLOR, SHELLY_MAX_COLOR, 0, 0);
         } else if (color.equals(SHELLY_COLOR_WHITE)) {
-            col.setRGBW(0, 0, 0, SHELLY_MAX_COLOR);
+            if (profile.isProRgbwwPm) { // RGB component has no white output, mix full RGB instead
+                col.setRGBW(SHELLY_MAX_COLOR, SHELLY_MAX_COLOR, SHELLY_MAX_COLOR, 0);
+            } else {
+                col.setRGBW(0, 0, 0, SHELLY_MAX_COLOR);
+            }
             col.setMode(SHELLY_MODE_WHITE);
         } else {
             throw new IllegalArgumentException("Invalid full color selection: " + color);
@@ -474,6 +478,8 @@ private void setFullColor(String colorGroup, ShellyColorUtils col) {
             updateChannel(colorGroup, CHANNEL_COLOR_FULL, new StringType(SHELLY_COLOR_BLUE));
         } else if ((col.red == 0) && (col.green == 0) && (col.blue == 0) && (col.white == SHELLY_MAX_COLOR)) {
             updateChannel(colorGroup, CHANNEL_COLOR_FULL, new StringType(SHELLY_COLOR_WHITE));
+        } else if ((col.red == SHELLY_MAX_COLOR) && (col.green == SHELLY_MAX_COLOR) && (col.blue == SHELLY_MAX_COLOR)) {
+            updateChannel(colorGroup, CHANNEL_COLOR_FULL, new StringType(SHELLY_COLOR_WHITE));
         }
     }