Hue - Parse Level / Color

I would like to have a rule that can increase the brightness of a hue/lifx bulb, but not change the colour (what ever it is)! From what I can understand these values are stored in the format (color,sat,brightness). Is there an easy way to parse the values, and then reformat changing only the brightness?

Out of curiosity, why would these not be stored as separate values to start with?

Item ‘hue_0200_0017881182b3_4_color’ received command 0,0,0