const PERSIAN_DIGITS = "۰۱۲۳۴۵۶۷۸۹";

export const localizeDigits = (value: string, lang: "en" | "fa") =>
  lang === "fa" ? value.replace(/\d/g, (digit) => PERSIAN_DIGITS[Number(digit)] || digit) : value;

export const currencyLabel = (currency: string, lang: "en" | "fa") => {
  const normalized = currency.toUpperCase();
  if (lang !== "fa") return normalized;
  return (
    {
      USD: "دلار آمریکا",
      EUR: "یورو",
      GBP: "پوند",
      IRR: "ریال",
      IRT: "تومان",
      AED: "درهم",
      TRY: "لیر",
    }[normalized] || normalized
  );
};

export const shouldTrimCurrencyDecimals = (currency?: string | null) => {
  const normalized = (currency || "").toUpperCase();
  return normalized === "IRR" || normalized === "IRT";
};

export const formatAmountForCurrency = (
  value: string,
  currency: string | null | undefined,
  lang: "en" | "fa",
) => {
  const trimmed = value.trim();
  if (!trimmed) return trimmed;
  const normalizedValue = trimmed.replace(/,/g, "");
  const numeric = Number(normalizedValue);
  if (Number.isNaN(numeric)) return localizeDigits(trimmed, lang);

  const [integerPart, fractionalPart] = normalizedValue.split(".");
  const grouped = Math.abs(Number(integerPart)).toLocaleString("en-US");
  const signed = normalizedValue.startsWith("-") ? `-${grouped}` : grouped;
  let formatted = signed;

  if (fractionalPart) {
    const nextFraction = shouldTrimCurrencyDecimals(currency)
      ? ""
      : fractionalPart.replace(/0+$/, "");
    if (nextFraction) {
      formatted = `${formatted}.${nextFraction}`;
    }
  }

  return localizeDigits(formatted, lang);
};

export const formatMoneyTotals = (
  totals: { currency: string; amount: string }[],
  lang: "en" | "fa",
) => {
  if (!totals.length) return "-";
  return totals
    .map((item) => `${formatAmountForCurrency(item.amount, item.currency, lang)} ${currencyLabel(item.currency, lang)}`)
    .join(" | ");
};

export const formatRateDisplay = (
  rate: { amount?: string | null; hourly_rate?: string | null; currency: string; price_unit?: { code?: string; local_name?: string; name?: string } | null } | null,
  lang: "en" | "fa",
) => {
  if (!rate) return "-";
  const amount = rate.amount ?? rate.hourly_rate ?? "";
  const unitLabel =
    lang === "fa"
      ? rate.price_unit?.local_name || rate.price_unit?.code || currencyLabel(rate.currency, lang)
      : rate.price_unit?.code || rate.currency;
  return `${formatAmountForCurrency(amount, rate.currency, lang)} ${unitLabel}`;
};