export function sanitizeUrl (url) {
  /** A pattern that matches safe  URLs. */
  const SAFE_URL_PATTERN =
    /^(?:(?:https?|mailto|ftp|tel|file|sms):|[^&:/?#]*(?:[/?#]|$))/gi

  /** A pattern that matches safe data URLs. */
  const DATA_URL_PATTERN =
    /^data:(?:image\/(?:bmp|gif|jpeg|jpg|png|tiff|webp)|video\/(?:mpeg|mp4|ogg|webm)|audio\/(?:mp3|oga|ogg|opus));base64,[a-z0-9+/]+=*$/i

  url = String(url).trim()

  if (url.match(SAFE_URL_PATTERN) || url.match(DATA_URL_PATTERN)) return url

  return 'https://'
}

// Source: https://stackoverflow.com/a/8234912/2013580
const urlRegExp =
  /((([A-Za-z]{3,9}:(?:\/\/)?)(?:[-;:&=+$,\w]+@)?[A-Za-z0-9.-]+|(?:www.|[-;:&=+$,\w]+@)[A-Za-z0-9.-]+)((?:\/[+~%/.\w-_]*)?\??(?:[-+=&;%@.\w_]*)#?(?:[\w]*))?)/
export function validateUrl (url) {
  // TODO Fix UI for link insertion; it should never default to an invalid URL such as https://.
  // Maybe show a dialog where they user can type the URL before inserting it.
  return url === 'https://' || urlRegExp.test(url)
}