/**
 * GST (Canadian Sales Tax Number)
 *
 * It is the BN in a extensive form.
 *   9 digits - Business number to identify the business. It is the Bussines Number.
 *   2 alpha - A reference number to identify each account a business may have within a program type.
 *   4 digits - A reference number to identify each account a business may have within a program type.
 *
 * Source
 *   https://wiki.scn.sap.com/wiki/display/CRM/Canada
 *   https://www.canada.ca/en/revenue-agency/cra-canada.html
 *
 * ENTITY
 */

import * as exceptions from '../exceptions';
import { strings } from '../util';
import { Validator, ValidateReturn } from '../types';
import { validate as bnValidate } from './bn';

function clean(input: string): ReturnType<typeof strings.cleanUnicode> {
  return strings.cleanUnicode(input, ' -');
}

const validRe = /^\d{9}[A-Z]{2}\d{4}$/i;

// const ALPHABET = '0123456789X';

const impl: Validator = {
  name: 'Goods and service Tax Number',
  localName: 'Goods and service Tax Number',
  abbreviation: 'GST',

  compact(input: string): string {
    const [value, err] = clean(input);

    if (err) {
      throw err;
    }

    return value;
  },

  format(input: string): string {
    const [value] = clean(input);

    return value;
  },

  validate(input: string): ValidateReturn {
    const [value, error] = clean(input);

    if (error) {
      return { isValid: false, error };
    }
    if (value.length !== 15) {
      return { isValid: false, error: new exceptions.InvalidLength() };
    }

    if (!validRe.test(value)) {
      return { isValid: false, error: new exceptions.InvalidFormat() };
    }

    // The BN15 is the same as a GST
    return bnValidate(value);
  },
};

export const { name, localName, abbreviation, validate, format, compact } =
  impl;