Class MouseObserver

scripts/libs/utils/mouseObserver.js:8–162

 */

export class MouseObserver {
  constructor(observeOpt) {
    this.observer = new IntersectionObserver((infoList) => {
      infoList.forEach((info) => {
        info.target.IntersectionObserverEntry = info;
      });
    }, observeOpt || {});

    this.observeList = [];
  }

  _observe(target) {
    let hasObserve = false;
    for (let i = 0; i < this.observeList.length; i++) {
      const el = this.observeList[i];
      if (target === el) {
        hasObserve = true;
        break;
      }
    }

    if (!hasObserve) {
      this.observer.observe(target);
      this.observeList.push(target);
    }
  }

  _unobserve(target) {
    this.observer.unobserve(target);
    const newObserveList = [];
    this.observeList.forEach((el) => {
      if (el !== target) {
        newObserveList.push(el);
      }
    });
    this.observeList = newObserveList;
  }

  /**
   * Add event binding
   * @param target {element} - required The DOM object to which the event is to be bound
   * @param type {string} - required The event to be bound, only mouse events are supported
   * @param listener {function} - required response function when triggering conditions are met
   */
  on(target, type, listener, options) {
    const t = this;
    t._observe(target);

    if (!target.MouseObserverEvent) {
      target.MouseObserverEvent = {};
    }
    target.MouseObserverEvent[type] = true;

    if (!t._mouseObserver_) {
      t._mouseObserver_ = {};
    }

    if (!t._mouseObserver_[type]) {