Use hue/sat as internal light color interface

[emlove]

Description:

This PR converts hass to use hue/sat as the core interface for colors. Platforms will only receive turn_on calls with hue/sat, and only need to report their entity colors in hue/sat. The light component will convert incoming service calls in other formats to hue/sat, and will make the entity colors in hue/sat from the platforms available to clients in RGB and XY form as well.

The use-case I have in mind is that I've been digging into the ZHA platform, and it natively prefers to work with XY colors instead of RGB. I think it's best if we just let the light component do the translation, so that platforms don't need to worry about supporting multiple formats, and can implement their preferred method. Doing the conversion in one place should also help give consistent behavior on how brightness is handled.

• Decide on HS color scaling
• Documentation updates: New hue/sat field on light.turn_on schema home-assistant.io#4881
• Polymer updates: Use new light HS API for the color picker frontend#982

[pvizeli]

I think you should merge this into preprocess_turn_on_alternatives. This function is for handling stuff like this.

I like this.

[emlove]

That's what I was thinking, but preprocess_turn_on_alternatives runs once for the service call, and isn't aware of the entities capabilities.

Another alternative would be to always transform color requests to XY in preprocess_turn_on_alternatives before sending them to the platforms. RGB only platforms would still have to convert incoming requests, but at least then platforms wouldn't have to worry about supporting multiple color request types.

[pvizeli]

The best would be, that home-assistant support only one color schema and all other need be converted. That what we have currently is bad by design. Anyway, I think we should convert it in any case like the others does.

[emlove]

👍 I think in an ideal world we'd only support XY color, since RGB has the confusing overlap with brightness. Unfortunately I don't think we can get away from RGB in the API since it's so ubiquitously understood, but we can at least limit the complexity of what is sent to platforms.

[balloob]

You should make a copy before mutating

[amelchio]

I will just remind that you advised against doing this in my old PR #6727 (comment)

I am not saying that this should exclude you from doing the change now, it is certainly acceptable to change your mind. However, I wonder whether your new use-case is perhaps blinding you from seeing the larger picture that you identified in my PR.

[emlove]

😆 Thanks for bringing that up! Those notes are some good context.

I think I've come to a better solution here thanks to this feedback, that hopefully keeps complexity limited.

[balloob]

I agree with @armills . The concerns by @amelchio are good but let's fix those in another PR. As is we're having a good foundation to build upon.

[OttoWinter]

Light groups and all the MQTT platforms look good 👍

[moskovskiy82]

Is this the reason MQTT RGB broke up?

https://community.home-assistant.io/t/0-66-rgb-mqtt/48871

@armills @balloob can you help identify the root cause?

[jamesw4]

I think this might be related to my issue with tradfri bulbs paired with hue hub? #13614

[Arkadyf]

Since change 89c7c80 (on Mar 18) to tplink.py, my TP-Link lights stopped supporting color. Color used to work in HA (on the UI or by setting color using commands) before that change, and the lights support color when using the Kasa app.
Since the change (89c7c80), changing lights only adjusts the brightness. Color selector appears in the HA UI, but it only affects brightness. Same API calls / automations / Node-red. I tried the "rgb_color" and the "color_name" to try to set the color. Both worked before.
Color still works in the Kasa app.

I'm new to this, so I don't know what other info I could provide to troubleshoot this.

[amelchio]

@Arkadyf No more information is needed but please create a separate GitHub issue. You can add a note that the problem probably is due to us no longer casting hsv to integers.