import { browserSupportsPassiveEventHandlers } from "./browserSupportsPassiveEventHandlers";
import { isTouchDevice } from "./isTouchDevice";

// This is primarily used for tooltips which behave differently on touch.
// For example, tooltips are commonly toggled on touch or disabled completely.
// To detect if mousemove is actually caused by a touch event, we check
// if device supports touch events and when the last touch event happened.
// Touch detection might cause bad scroll performance on devices which do not
// support passive event listeners, and in that case detection relies only on
// presence of touch events, without inspection of each event.

let insideTouchEvent = 0;
let lastTouchEvent = 0;
let isTouchDetectionEnabled = false;

export function enableTouchEventDetection(): void {
   if (isTouchDevice() && !isTouchDetectionEnabled) {
      let options: boolean | AddEventListenerOptions = true; //capture

      if (browserSupportsPassiveEventHandlers())
         options = {
            passive: true,
            capture: true,
         };

      document.addEventListener(
         "touchstart",
         () => {
            insideTouchEvent++;
            //console.log('TOUCHSTART');
            lastTouchEvent = Date.now();
         },
         options,
      );

      document.addEventListener(
         "touchmove",
         () => {
            //console.log('TOUCHMOVE');
            lastTouchEvent = Date.now();
         },
         options,
      );

      document.addEventListener(
         "touchend",
         () => {
            insideTouchEvent--;
            lastTouchEvent = Date.now();
            //console.log('TOUCHEND');
         },
         options,
      );

      isTouchDetectionEnabled = true;
   }
}

export function isTouchEvent(): boolean {
   return isTouchDevice() && (!isTouchDetectionEnabled || Date.now() - lastTouchEvent < 1000);
}

//enable touch event detection if there is no performance penalty on scrolling
if (isTouchDevice() && browserSupportsPassiveEventHandlers()) enableTouchEventDetection();