forked from validatorjs/validator.js
/
isCreditCard.js
33 lines (31 loc) · 1 KB
/
isCreditCard.js
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import assertString from './util/assertString';
/* eslint-disable max-len */
const creditCard = /^(?:4[0-9]{12}(?:[0-9]{3,6})?|5[1-5][0-9]{14}|(222[1-9]|22[3-9][0-9]|2[3-6][0-9]{2}|27[01][0-9]|2720)[0-9]{12}|6(?:011|5[0-9][0-9])[0-9]{12,15}|3[47][0-9]{13}|3(?:0[0-5]|[68][0-9])[0-9]{11}|(?:2131|1800|35\d{3})\d{11}|6[27][0-9]{14}|^(81[0-9]{14,17}))$/;
/* eslint-enable max-len */
export default function isCreditCard(str) {
assertString(str);
const sanitized = str.replace(/[- ]+/g, '');
if (!creditCard.test(sanitized)) {
return false;
}
let sum = 0;
let digit;
let tmpNum;
let shouldDouble;
for (let i = sanitized.length - 1; i >= 0; i--) {
digit = sanitized.substring(i, (i + 1));
tmpNum = parseInt(digit, 10);
if (shouldDouble) {
tmpNum *= 2;
if (tmpNum >= 10) {
sum += ((tmpNum % 10) + 1);
} else {
sum += tmpNum;
}
} else {
sum += tmpNum;
}
shouldDouble = !shouldDouble;
}
return !!((sum % 10) === 0 ? sanitized : false);
}