import {Service, Utils} from "../imports.js"
const {exec, execAsync} = Utils

const clamp = (num, min, max) => Math.min(Math.max(num, min), max)

class BrightnessService extends Service {
  static {
    Service.register(this, {"screen-changed": ["float"]}, {"screen-value": ["float", "rw"]})
  }

  _screenValue = 0

  // the getter has to be in snake_case
  get screen_value() {
    return this._screenValue
  }

  // the setter has to be in snake_case too
  set screen_value(percent) {
    percent = clamp(percent, 0, 1)
    this._screenValue = percent

    Utils.execAsync(`brightnessctl s ${percent * 100}% -q`)
      .then(() => {
        // signals has to be explicity emitted
        this.emit("screen-changed", percent)
        this.notify("screen-value")

        // or use Service.changed(propName: string) which does the above two
        // this.changed('screen');
      })
      .catch(print)
  }

  constructor() {
    super()
    const current = Number(exec("brightnessctl g"))
    const max = Number(exec("brightnessctl m"))
    this._screenValue = current / max
  }

  // overwriting connectWidget method, let's you
  // change the default event that widgets connect to
  connectWidget(widget, callback, event = "screen-changed") {
    super.connectWidget(widget, callback, event)
  }
}

// the singleton instance
const service = new BrightnessService()

// make it global for easy use with cli
globalThis.brightness = service

// export to use in other modules
export default service