/**
 * Persian/Arabic-Indic digits to ASCII.
 *
 * Port of the reference's `Utility::faTOen()`, which every mobile number and
 * every submitted OTP code passes through before being compared
 * (henza_server ApiMobileController.php:42,56). The app's numeric keypad emits
 * Persian digits, so without this a user typing ۱۲۳۴ would never match a stored
 * 1234 and the phone lookup would miss a registered customer entirely.
 *
 * Kept in its own module, free of Nest and Prisma imports, so it can be unit
 * tested without booting the DI container.
 */
export function faToEn(input: string): string {
  return input
    .replace(/[۰-۹]/g, (d) => String(d.charCodeAt(0) - 0x06f0))
    .replace(/[٠-٩]/g, (d) => String(d.charCodeAt(0) - 0x0660))
    .trim();
}