How to use the screenfull.exit function in screenfull

export function exitFullScreen() {
    if (typeof document === 'undefined') return /* Build time render by Gatsby. */
    if (!screenfull.enabled) return /* Browser prevents full screen or problem with library. */
    if (screenfull.isFullscreen) {
        screenfull.exit()
    }
}

return new Promise(resolve => {
        if (screenfull.isFullscreen) {
          screenfull.exit()
          commit('set', false)
        } else {
          screenfull.request()
          commit('set', true)
        }
        // end
        resolve()
      })
    }

disengage(): void {
        if (!this._engaged) {
            return;
        }

        if (noFullscrenApi || !screenfull) {
            this._resetSize();
            window.removeEventListener('resize', this._resizeListener);
            this._engaged = false;
        } else {
            screenfull.exit();
        }
    }

closeFullscreen() {
      return this.fullscreen && screenfull && screenfull.isEnabled && !(isMobile() && isFirefox()) ? screenfull.exit() : Promise.resolve(false);
    }

onClickFullscreen() {
        if(!this.state.fullscreen) {
            screenfull.request(findDOMNode(this.pdf_wrapper));
        } else {
            screenfull.exit();
        }
        this.setState({ fullscreen: !this.state.fullscreen });
    }

onClickFullscreen() {
        if(!this.state.fullscreen) {
            screenfull.request(findDOMNode(this.pdf_wrapper));
        } else {
            screenfull.exit();
        }
        this.setState({ fullscreen: !this.state.fullscreen });
    }

this.orbitControl.enabled = true;
      this.orbitControl.target.set(x, y, z);
    } else {
      selectedComponent = undefined;
      this.presentation.blur();
    }

    if (mode === EditorMode.PLAY) {
      this.presentation.play();
      this.orbitControl.enabled = false;
      this.transformControl.enabled = false;
      this.transformControl.detach();
      if (Screenfull) Screenfull.request(this.presentation.domElement);
      this.presentation.resize(window.innerWidth, window.innerHeight);
    } else if (this.state.mode === EditorMode.PLAY) {
      if (Screenfull) Screenfull.exit();
    }

    this.setState({
      mode,
      selectedComponent
    });
  }

const exitFull = useCallback(() => {
    const passedInElement = typeof dom === 'function' ? dom() : dom;
    const targetElement = passedInElement || element.current;
    if (!targetElement) {
      return;
    }
    if (screenfull.isEnabled) {
      screenfull.exit();
    }
  }, [typeof dom === 'function' ? undefined : dom]);

componentWillUnmount() {
    document.removeEventListener("keydown", this.onKeydown);
    document.removeEventListener("keyup", this.onKeyUp);
    document.removeEventListener("touchstart", this.onTouchStart);
    if (Screenfull) Screenfull.exit();
  }