validate method

Either<PasswordError, String> validate(String input)

Validates the given input string as a password.

Implementation

Either<PasswordError, String> validate(String input) {
  if (input.isEmpty) {
    return const Left(PasswordEmpty());
  }

  if (input.length < config.minLength) {
    return Left(
      PasswordTooShort(
        currentLength: input.length,
        minLength: config.minLength,
      ),
    );
  }

  if (input.length > config.maxLength) {
    return Left(
      PasswordTooLong(
        currentLength: input.length,
        maxLength: config.maxLength,
      ),
    );
  }

  if (!_isAsciiOnly(input)) {
    return const Left(PasswordNonAscii());
  }

  final lowered = input.toLowerCase();

  if (_hasCommonPasswordPrefix(lowered)) {
    return const Left(PasswordTooCommon());
  }

  if (v.PasswordValidator.hasOnlyRepeatedCharacters(input)) {
    return const Left(PasswordTooWeak());
  }

  final maxAllowedRun = (input.length * config.sequentialRunFactor)
      .floor()
      .clamp(3, 7);
  if (v.PasswordValidator.hasSequentialRun(lowered, minRun: maxAllowedRun)) {
    return const Left(PasswordTooPredictable());
  }

  final score = _classScore(input);
  if (score < config.minComplexityScore) {
    return Left(
      PasswordComplexityRequired(
        currentScore: score,
        requiredScore: config.minComplexityScore,
      ),
    );
  }

  return Right(input);
}