import { bash, dependencies, sh } from "../lib/utils.js"

if (!dependencies("brightnessctl"))
  App.quit()

const get = (args) => Number(Utils.exec(`brightnessctl ${args}`))
const screen = await bash`ls -w1 /sys/class/backlight | head -1`
const kbd = await bash`ls -w1 /sys/class/leds | head -1`

class Brightness extends Service {
  static {
    Service.register(this, {}, {
      "screen": ["float", "rw"],
      "kbd": ["int", "rw"],
    })
  }

  #kbdMax = get(`--device ${kbd} max`)
  #kbd = get(`--device ${kbd} get`)
  #screenMax = get("max")
  #screen = get("get") / get("max")

  get kbd() { return this.#kbd }
  get screen() { return this.#screen }

  set kbd(value) {
    if (value < 0 || value > this.#kbdMax)
      return

    sh(`brightnessctl -d ${kbd} s ${value} -q`).then(() => {
      this.#kbd = value
      this.changed("kbd")
    })
  }

  set screen(percent) {
    if (percent < 0)
      percent = 0

    if (percent > 1)
      percent = 1

    sh(`brightnessctl set ${Math.floor(percent * 100)}% -q`).then(() => {
      this.#screen = percent
      this.changed("screen")
    })
  }

  constructor() {
    super()

    const screenPath = `/sys/class/backlight/${screen}/brightness`
    const kbdPath = `/sys/class/leds/${kbd}/brightness`

    Utils.monitorFile(screenPath, async f => {
      const v = await Utils.readFileAsync(f)
      this.#screen = Number(v) / this.#screenMax
      this.changed("screen")
    })

    Utils.monitorFile(kbdPath, async f => {
      const v = await Utils.readFileAsync(f)
      this.#kbd = Number(v) / this.#kbdMax
      this.changed("kbd")
    })
  }
}

export default new Brightness()