Model.js

.pragma library

// The light reports colour temperature in mireds and accepts nothing outside
// 143-344 — it ignores out-of-range values rather than clamping them, so a
// slider allowed past the end would silently stop responding.
var KELVIN_MIN = 2900
var KELVIN_MAX = 7000

var ICON_ON = "󰛨"
var ICON_OFF = "󰌵"
var ICON_DOWN = "󰅤"

function clamp(value, low, high) {
  if (isNaN(value)) return low
  return Math.max(low, Math.min(high, value))
}

// Kelvin steps of 50 match what the device can actually resolve; finer steps
// just produce values that read back as something else.
function snapKelvin(kelvin) {
  return Math.round(clamp(kelvin, KELVIN_MIN, KELVIN_MAX) / 50) * 50
}

// omarchy-keylight prints one short line; anything longer didn't come from it.
var MAX_OUTPUT = 4096

function parse(text) {
  var raw = String(text || "").trim()
  if (raw.length > MAX_OUTPUT) return null
  try {
    var parsed = JSON.parse(raw)
    if (!parsed || parsed.reachable !== true) return null
    return {
      on: parsed.on === 1,
      brightness: clamp(parseInt(parsed.brightness, 10), 0, 100),
      kelvin: snapKelvin(parseInt(parsed.kelvin, 10))
    }
  } catch (e) {
    return null
  }
}

function icon(reachable, on) {
  if (!reachable) return ICON_DOWN
  return on ? ICON_ON : ICON_OFF
}

function tooltip(reachable, on, brightness, kelvin) {
  if (!reachable) return "Key Light — not reachable"
  if (!on) return "Key Light — off"
  return "Key Light — " + brightness + "%, " + kelvin + "K"
}