se-panfilov/jsvat

import { Country } from '../jsvat';

export const croatia: Country = {
  name: 'Croatia',
  codes: ['HR', 'HRV', '191'],
  calcFn: (vat: string): boolean => {
    // Checks the check digits of a Croatian VAT number using ISO 7064, MOD 11-10 for check digit.
    let product = 10;
    let sum = 0;

    for (let i = 0; i < 10; i++) {
      // Extract the next digit and implement the algorithm
      sum = (Number(vat.charAt(i)) + product) % 10;
      if (sum === 0) {
        sum = 10;
      }

      product = (2 * sum) % 11;
    }

    // Now check that we have the right check digit
    const expect = Number(vat.slice(10, 11));
    return (product + expect) % 10 === 1;
  },
  rules: {
    multipliers: {},
    regex: [/^(HR)(\d{11})$/]
  }
};