export function hasClass(el, className) {
  const reg = new RegExp('(^|\\s)' + className + '(\\s|$)')
  return reg.test(el.className)
}

export function addClass(el, className) {
  if (hasClass(el, className)) {
    return
  }

  const newClass = el.className.split(' ')
  newClass.push(className)
  el.className = newClass.join(' ')
}

export function removeClass(el, className) {
  if (!hasClass(el, className)) {
    return
  }

  const reg = new RegExp('(^|\\s)' + className + '(\\s|$)', 'g')
  el.className = el.className.replace(reg, ' ')
}

export function getData(el, name) {
  const prefix = 'data-'
  return el.getAttribute(prefix + name)
}

export function getRect(el) {
  return {
    top: el.offsetTop,
    left: el.offsetLeft,
    width: el.offsetWidth,
    height: el.offsetHeight
  }
}