function debounce(func, wait, immediate) {
  let timeout;
  return function() {
    const context = this;
    const args = arguments;
    const later = () => {
      timeout = null;
      if (!immediate) {
        func.apply(context, args);
      }
    };
    const callNow = immediate && !timeout;
    clearTimeout(timeout);
    timeout = setTimeout(later, wait);
    if (callNow) {
      func.apply(context, args);
    }
  };
}
Returns a function, that, as long as it continues to be invoked, will not
be triggered. The function will be called after it stops being called for
N milliseconds. If `immediate` is passed, trigger the function on the
leading edge, instead of the trailing.
@param {Function} func
@param {Number} wait
@param {Boolean} immediate
@return {Function}