class Power {
  constructor() {
    this._shutdown = document.querySelector("#shutdown-button");
    this._restart = document.querySelector("#restart-button");
    this._hibernate = document.querySelector("#hibernate-button");
    this._suspend = document.querySelector("#suspend-button");
    this._cover = document.querySelector("#cover");
    this._covermsg = document.querySelector("#cover > #message");
    this._init();
  }

  _show_message(text) {
    this._covermsg.innerHTML = text;
    this._cover.classList.remove("hide");
    wait(500).then(() => {
      this._cover.focus();
    });
  }

  async _do_shutdown() {
    this._show_message("Shutting down");
    await wait(1000);
    lightdm.shutdown();
  }
  async _do_restart() {
    this._show_message("Restarting");
    await wait(1000);
    lightdm.restart();
  }
  async _do_hibernate() {
    this._show_message("Hibernating");
    await wait(1000);
    lightdm.hibernate();
  }
  async _do_suspend() {
    this._show_message("Suspending");
    await wait(1000);
    lightdm.suspend();
  }

  _setShutdown() {
    if (!lightdm.can_shutdown) return;
    this._shutdown.addEventListener("click", () => {
      this._do_shutdown();
    });
    this._shutdown.classList.remove("hide");
  }
  _setRestart() {
    if (!lightdm.can_restart) return;
    this._restart.addEventListener("click", () => {
      this._do_restart();
    });
    this._restart.classList.remove("hide");
  }
  _setHibernate() {
    if (!lightdm.can_hibernate) return;
    this._hibernate.addEventListener("click", () => {
      this._do_hibernate();
    });
    this._hibernate.classList.remove("hide");
  }
  _setSuspend() {
    if (!lightdm.can_suspend) return;
    this._suspend.addEventListener("click", () => {
      this._do_suspend();
    });
    this._suspend.classList.remove("hide");
  }
  _setCover() {
    this._cover.addEventListener("click", () => {
      this._cover.classList.add("hide");
    });
    this._cover.addEventListener("keydown", () => {
      this._cover.classList.add("hide");
    });
  }

  _setButtons() {
    this._setShutdown();
    this._setRestart();
    this._setHibernate();
    this._setSuspend();
    this._setCover();
  }

  _init() {
    this._setButtons();
  }
}