import { GET_BY_ISO639 } from '../../sql/language.js';
import request from '../request.js';

export default function getByIso639(pool) {
  /**
   * Returns a language row by its ISO 639 code.
   *
   * @param {string} iso639 - The ISO 639 language code (e.g. `'de'`).
   * @param {object} [tx] - Optional transaction to run within.
   * @returns {Promise<{id: number, iso639: string}>} The language row, or `undefined` if not found.
   *
   * @example
   * const lang = await store.lang.getByIso639('de');
   * // => { id: 1, iso639: 'de' }
   */
  return async (iso639, tx) => {
    const result = await request(pool, tx)
      .input('iso639', iso639)
      .query(GET_BY_ISO639);

    return result.recordset[0];
  };
}