annotate vendor/symfony/validator/Constraints/LuhnValidator.php @ 19:fa3358dc1485 tip

Add ndrum files
author Chris Cannam
date Wed, 28 Aug 2019 13:14:47 +0100
parents 129ea1e6d783
children
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Chris@0 1 <?php
Chris@0 2
Chris@0 3 /*
Chris@0 4 * This file is part of the Symfony package.
Chris@0 5 *
Chris@0 6 * (c) Fabien Potencier <fabien@symfony.com>
Chris@0 7 *
Chris@0 8 * For the full copyright and license information, please view the LICENSE
Chris@0 9 * file that was distributed with this source code.
Chris@0 10 */
Chris@0 11
Chris@0 12 namespace Symfony\Component\Validator\Constraints;
Chris@0 13
Chris@0 14 use Symfony\Component\Validator\Constraint;
Chris@0 15 use Symfony\Component\Validator\ConstraintValidator;
Chris@0 16 use Symfony\Component\Validator\Exception\UnexpectedTypeException;
Chris@0 17
Chris@0 18 /**
Chris@0 19 * Validates a PAN using the LUHN Algorithm.
Chris@0 20 *
Chris@0 21 * For a list of example card numbers that are used to test this
Chris@0 22 * class, please see the LuhnValidatorTest class.
Chris@0 23 *
Chris@0 24 * @see http://en.wikipedia.org/wiki/Luhn_algorithm
Chris@0 25 *
Chris@0 26 * @author Tim Nagel <t.nagel@infinite.net.au>
Chris@0 27 * @author Greg Knapp http://gregk.me/2011/php-implementation-of-bank-card-luhn-algorithm/
Chris@0 28 * @author Bernhard Schussek <bschussek@gmail.com>
Chris@0 29 */
Chris@0 30 class LuhnValidator extends ConstraintValidator
Chris@0 31 {
Chris@0 32 /**
Chris@0 33 * Validates a credit card number with the Luhn algorithm.
Chris@0 34 *
Chris@0 35 * @param mixed $value
Chris@0 36 * @param Constraint $constraint
Chris@0 37 *
Chris@0 38 * @throws UnexpectedTypeException when the given credit card number is no string
Chris@0 39 */
Chris@0 40 public function validate($value, Constraint $constraint)
Chris@0 41 {
Chris@0 42 if (!$constraint instanceof Luhn) {
Chris@0 43 throw new UnexpectedTypeException($constraint, __NAMESPACE__.'\Luhn');
Chris@0 44 }
Chris@0 45
Chris@0 46 if (null === $value || '' === $value) {
Chris@0 47 return;
Chris@0 48 }
Chris@0 49
Chris@0 50 // Work with strings only, because long numbers are represented as floats
Chris@0 51 // internally and don't work with strlen()
Chris@17 52 if (!\is_string($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
Chris@0 53 throw new UnexpectedTypeException($value, 'string');
Chris@0 54 }
Chris@0 55
Chris@0 56 $value = (string) $value;
Chris@0 57
Chris@0 58 if (!ctype_digit($value)) {
Chris@0 59 $this->context->buildViolation($constraint->message)
Chris@0 60 ->setParameter('{{ value }}', $this->formatValue($value))
Chris@0 61 ->setCode(Luhn::INVALID_CHARACTERS_ERROR)
Chris@0 62 ->addViolation();
Chris@0 63
Chris@0 64 return;
Chris@0 65 }
Chris@0 66
Chris@0 67 $checkSum = 0;
Chris@17 68 $length = \strlen($value);
Chris@0 69
Chris@0 70 // Starting with the last digit and walking left, add every second
Chris@0 71 // digit to the check sum
Chris@0 72 // e.g. 7 9 9 2 7 3 9 8 7 1 3
Chris@0 73 // ^ ^ ^ ^ ^ ^
Chris@0 74 // = 7 + 9 + 7 + 9 + 7 + 3
Chris@0 75 for ($i = $length - 1; $i >= 0; $i -= 2) {
Chris@0 76 $checkSum += $value[$i];
Chris@0 77 }
Chris@0 78
Chris@0 79 // Starting with the second last digit and walking left, double every
Chris@0 80 // second digit and add it to the check sum
Chris@0 81 // For doubles greater than 9, sum the individual digits
Chris@0 82 // e.g. 7 9 9 2 7 3 9 8 7 1 3
Chris@0 83 // ^ ^ ^ ^ ^
Chris@0 84 // = 1+8 + 4 + 6 + 1+6 + 2
Chris@0 85 for ($i = $length - 2; $i >= 0; $i -= 2) {
Chris@0 86 $checkSum += array_sum(str_split($value[$i] * 2));
Chris@0 87 }
Chris@0 88
Chris@0 89 if (0 === $checkSum || 0 !== $checkSum % 10) {
Chris@0 90 $this->context->buildViolation($constraint->message)
Chris@0 91 ->setParameter('{{ value }}', $this->formatValue($value))
Chris@0 92 ->setCode(Luhn::CHECKSUM_FAILED_ERROR)
Chris@0 93 ->addViolation();
Chris@0 94 }
Chris@0 95 }
Chris@0 96 }