/** Changes the expire date and alert for the new specified */
  @RequestMapping(value = "/changeExpire", method = RequestMethod.GET)
  public ResponseEntity<?> changeExpireDate(
      HttpServletRequest request,
      @RequestParam(value = "url", required = false) String hash,
      @RequestParam(value = "expire", required = false) String expire,
      @RequestParam(value = "days", required = false) String days) {
    hash = hash.substring(1, hash.length() - 1);

    /* Changes expire date */
    ShortURL su = shortURLRepository.findByHash(hash);
    logger.info("su: " + su);
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
    Date newExpire = null;
    try {
      newExpire = sdf.parse(expire);
    } catch (ParseException e) {
      e.printStackTrace();
      logger.info("Error with introduced alert date");
    }
    su.setExpire(newExpire);
    logger.info("Updating ShortURL: " + su);
    shortURLRepository.save(su);

    /* Changes alert date */
    Alert a = alertRepository.findByHash(hash);
    Date alertDate = processAlertDate(expire, days);
    if (a != null) {
      /* If alert already exists, updates its alert date */
      a.setDate(alertDate);
      logger.info("Updating alert: " + a);
      alertRepository.save(a);
    } else {
      /* If alert does not exist, creates a new one */
      String mail = UrlShortenerControllerWithLogs.getOwnerMail();
      logger.info("Setting new alert");
      alertRepository.save(new Alert(mail, hash, alertDate));
    }
    return new ResponseEntity<>(HttpStatus.OK);
  }
  /**
   * If shortURL is valid, creates it and saves it XXX: at the moment, it just ignores unknown
   * emails, with no feedback for users.
   */
  protected ShortURL createAndSaveIfValid(
      String url,
      String custom,
      String hasToken,
      String expireDate,
      String ip,
      String[] emails,
      Principal principal,
      String country) {

    UrlValidator urlValidator = new UrlValidator(new String[] {"http", "https"});
    /*
     * Check if url comes through http or https
     */
    if (urlValidator.isValid(url)) {
      logger.info("Shortening valid url " + url);
      /*
       * Creates a hash from the current date in case this is not custom
       */
      String id;
      String now = new Date().toString();
      if (custom.equals("")) {
        id = Hashing.murmur3_32().hashString(now, StandardCharsets.UTF_8).toString();
      } else {
        id = custom;
      }

      /*
       * Has Token
       */
      String token = null;
      if (hasToken != null && !hasToken.equals("")) {
        token = UUID.randomUUID().toString();
      }
      /*
       * Expire date
       */
      Date expire = null;
      if (!expireDate.equals("")) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        try {
          expire = sdf.parse(expireDate);
        } catch (ParseException e) {
          e.printStackTrace();
          logger.info("Error: badly introduced date.");
        }
      }

      /*
       * Checks every mail inserted by the user, and maintains a list with
       * those corresponding to registered users.
       */
      List<String> trueEmails = new ArrayList<String>();
      for (int i = 0; i < emails.length; i++) {
        if (!emails[i].equals("")) {
          User foundUser = null;

          foundUser = userRepository.findByMail(emails[i]);
          if (foundUser != null) {
            trueEmails.add(foundUser.getMail());
          }
        }
      }

      /*
       * If no valid emails are introduced, link will be public and it
       * wont have an email list.
       */
      boolean isPrivate = false;
      if (trueEmails.size() > 0) {
        isPrivate = true;
      } else {
        trueEmails = null;
      }

      /*
       * Gets email
       */
      String owner = getOwnerMail();

      /*
       * Creates ShortURL object
       */
      ShortURL su =
          new ShortURL(
              id,
              url,
              linkTo(
                      methodOn(UrlShortenerControllerWithLogs.class)
                          .redirectTo(id, null, null, null, null))
                  .toUri(),
              new Date(System.currentTimeMillis()),
              expire,
              owner,
              token,
              HttpStatus.TEMPORARY_REDIRECT.value(),
              ip,
              country,
              isPrivate,
              trueEmails);

      /*
       * Insert to DB
       */
      return shortURLRepository.save(su);
    } else {
      logger.info("Not valid url " + url);
      return null;
    }
  }