const PERSIAN_DIGITS = '۰۱۲۳۴۵۶۷۸۹';
const ARABIC_DIGITS = '٠١٢٣٤٥٦٧٨٩';
const INVISIBLE_CHARS = /[\u200c\u200d\u202a-\u202e\ufeff]/g;

export const IRAN_MOBILE_REGEX = /^09\d{9}$/;

function toAsciiDigits(value: string): string {
  return value.replace(/[۰-۹٠-٩]/g, (ch) => {
    const persian = PERSIAN_DIGITS.indexOf(ch);
    if (persian >= 0) return String(persian);
    const arabic = ARABIC_DIGITS.indexOf(ch);
    if (arabic >= 0) return String(arabic);
    return ch;
  });
}

/** Normalize Iranian mobile to 09xxxxxxxxx (11 digits). */
export function normalizeIranMobile(raw: string): string {
  let mobile = toAsciiDigits(String(raw ?? '').trim());
  mobile = mobile.replace(INVISIBLE_CHARS, '');

  let digits = mobile.replace(/\D/g, '');
  if (!digits) return '';

  if (digits.startsWith('0098')) {
    digits = digits.slice(2);
  }
  if (digits.startsWith('98') && digits.length >= 12) {
    digits = `0${digits.slice(2)}`;
  } else if (digits.startsWith('9') && digits.length === 10) {
    digits = `0${digits}`;
  }

  return digits;
}

export function isValidIranMobile(mobile: string): boolean {
  return IRAN_MOBILE_REGEX.test(mobile);
}