new-server/webui/src/helpers/kelvin.ts

// @ts-ignore
import kelvinToRgb from "kelvin-to-rgb";
import {ColorValue} from "../models/Colors";
import iro from "@jaames/iro";

export function kelvinToColorValue(rawKelvin: number): ColorValue {
  const kelvin = normalizeKelvin(rawKelvin);

  return kelvinTable[kelvin];
}

export function kelvinToRgbHex(rawKelvin: number): string {
  const kelvin = normalizeKelvin(rawKelvin);

  const c = new iro.Color();
  c.kelvin = kelvin;

  return c.hexString;
}

function normalizeKelvin(kelvin: number): number {
  if (kelvin < 1000) {
    return 1000;
  } else if (kelvin > 10000) {
    return 10000;
  } else {
    return kelvin - (kelvin % 100);
  }
}

const kelvinTable: {[key: number]: ColorValue} = {};
for (let kelvin = 1000; kelvin <= 10000; kelvin += 100) {
  const c = new iro.Color();
  c.kelvin = kelvin;

  const [h, s] = [c.hsv.h, (c.hsv.s as number) / 100];

  kelvinTable[kelvin] = {h, s, kelvin};
}