import { pageYOffset, smoothScrollToElement } from './../utils/utils';

export default () => {
  const b2tButton = document.querySelector('.b2top-button');

  if (!b2tButton) {
    return;
  }

  const onb2tClick = () => {
    smoothScrollToElement(document.body);
  };

  b2tButton.addEventListener('click', onb2tClick);

  const showButton = () => {
    if (pageYOffset() > window.innerHeight * 1.02) {
      b2tButton.classList.add('js-visible');
    } else {
      b2tButton.classList.remove('js-visible');
    }
  };

  window.addEventListener('scroll', showButton);
};