const currencyFormatter = new Intl.NumberFormat('fa-IR', {
  maximumFractionDigits: 0,
})

const numberFormatter = new Intl.NumberFormat('fa-IR', {
  maximumFractionDigits: 2,
})

const jalaliDateFormatter = new Intl.DateTimeFormat('fa-IR-u-ca-persian', {
  year: 'numeric',
  month: '2-digit',
  day: '2-digit',
})

const jalaliDateTimeFormatter = new Intl.DateTimeFormat('fa-IR-u-ca-persian', {
  year: 'numeric',
  month: '2-digit',
  day: '2-digit',
  hour: '2-digit',
  minute: '2-digit',
})

/** Formats an amount as Toman with Persian digits and grouping. */
export function formatMoney(amount: number): string {
  return currencyFormatter.format(Math.round(amount))
}

export function formatMoneyWithUnit(amount: number, unit = 'تومان'): string {
  return `${formatMoney(amount)} ${unit}`
}

export function formatNumber(value: number): string {
  return numberFormatter.format(value)
}

/** Formats an ISO date string to a Jalali (Persian) date. */
export function formatDate(iso: string): string {
  const date = new Date(iso)
  if (Number.isNaN(date.getTime())) return '-'
  return jalaliDateFormatter.format(date)
}

export function formatDateTime(iso: string): string {
  const date = new Date(iso)
  if (Number.isNaN(date.getTime())) return '-'
  return jalaliDateTimeFormatter.format(date)
}

/** Returns today's date as an ISO yyyy-mm-dd string for date inputs. */
export function todayISO(): string {
  return new Date().toISOString().slice(0, 10)
}

const toPersianDigits = (input: string): string =>
  input.replace(/[0-9]/g, (digit) => '۰۱۲۳۴۵۶۷۸۹'[Number(digit)])

export function toFa(value: string | number): string {
  return toPersianDigits(String(value))
}