From 46e43f4bde4a35785b4997b81e86cd19f046b69b Mon Sep 17 00:00:00 2001
From: Minteck <contact@minteck.org>
Date: Tue, 21 Dec 2021 16:52:28 +0100
Subject: Commit

---
 src/node_modules/validator/lib/isEAN.js | 80 +++++++++++++++++++++++++++++++++
 1 file changed, 80 insertions(+)
 create mode 100644 src/node_modules/validator/lib/isEAN.js

(limited to 'src/node_modules/validator/lib/isEAN.js')

diff --git a/src/node_modules/validator/lib/isEAN.js b/src/node_modules/validator/lib/isEAN.js
new file mode 100644
index 0000000..098c44c
--- /dev/null
+++ b/src/node_modules/validator/lib/isEAN.js
@@ -0,0 +1,80 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.default = isEAN;
+
+var _assertString = _interopRequireDefault(require("./util/assertString"));
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+/**
+ * The most commonly used EAN standard is
+ * the thirteen-digit EAN-13, while the
+ * less commonly used 8-digit EAN-8 barcode was
+ * introduced for use on small packages.
+ * EAN consists of:
+ * GS1 prefix, manufacturer code, product code and check digit
+ * Reference: https://en.wikipedia.org/wiki/International_Article_Number
+ */
+
+/**
+ * Define EAN Lenghts; 8 for EAN-8; 13 for EAN-13
+ * and Regular Expression for valid EANs (EAN-8, EAN-13),
+ * with exact numberic matching of 8 or 13 digits [0-9]
+ */
+var LENGTH_EAN_8 = 8;
+var validEanRegex = /^(\d{8}|\d{13})$/;
+/**
+ * Get position weight given:
+ * EAN length and digit index/position
+ *
+ * @param {number} length
+ * @param {number} index
+ * @return {number}
+ */
+
+function getPositionWeightThroughLengthAndIndex(length, index) {
+  if (length === LENGTH_EAN_8) {
+    return index % 2 === 0 ? 3 : 1;
+  }
+
+  return index % 2 === 0 ? 1 : 3;
+}
+/**
+ * Calculate EAN Check Digit
+ * Reference: https://en.wikipedia.org/wiki/International_Article_Number#Calculation_of_checksum_digit
+ *
+ * @param {string} ean
+ * @return {number}
+ */
+
+
+function calculateCheckDigit(ean) {
+  var checksum = ean.slice(0, -1).split('').map(function (char, index) {
+    return Number(char) * getPositionWeightThroughLengthAndIndex(ean.length, index);
+  }).reduce(function (acc, partialSum) {
+    return acc + partialSum;
+  }, 0);
+  var remainder = 10 - checksum % 10;
+  return remainder < 10 ? remainder : 0;
+}
+/**
+ * Check if string is valid EAN:
+ * Matches EAN-8/EAN-13 regex
+ * Has valid check digit.
+ *
+ * @param {string} str
+ * @return {boolean}
+ */
+
+
+function isEAN(str) {
+  (0, _assertString.default)(str);
+  var actualCheckDigit = Number(str.slice(-1));
+  return validEanRegex.test(str) && actualCheckDigit === calculateCheckDigit(str);
+}
+
+module.exports = exports.default;
+module.exports.default = exports.default;
\ No newline at end of file
-- 
cgit