export function formatBytes(bytes?: number): string {
  if (!bytes) return '—';
  if (bytes < 1024) return `${bytes} B`;
  if (bytes < 1024 * 1024) return `${(bytes / 1024).toFixed(1)} KB`;
  return `${(bytes / (1024 * 1024)).toFixed(1)} MB`;
}

export function parseCpuToMillicores(cpu: string): number {
  if (!cpu) return 0;
  if (cpu.endsWith('m')) return parseFloat(cpu);
  return parseFloat(cpu) * 1000;
}

export function parseMemoryToMi(mem: string): number {
  if (!mem) return 0;
  if (mem.endsWith('Gi')) return parseFloat(mem) * 1024;
  if (mem.endsWith('Mi')) return parseFloat(mem);
  if (mem.endsWith('Ki')) return parseFloat(mem) / 1024;
  return parseFloat(mem);
}

/** Human-readable time left (days, hours, minutes). */
export function formatRemainingDurationMs(remainingMs: number): string {
  const ms = Math.max(0, remainingMs);
  const days = Math.floor(ms / 86400000);
  const hours = Math.floor((ms % 86400000) / 3600000);
  const minutes = Math.floor((ms % 3600000) / 60000);
  if (days > 0) return `${days}d ${hours}h ${minutes}m`;
  if (hours > 0) return `${hours}h ${minutes}m`;
  if (minutes > 0) return `${minutes}m`;
  return 'less than 1m';
}

/** Persian (با ارقام فارسی) human-readable time left, e.g. «۲۹ روز و ۱۹ ساعت و ۵۱ دقیقه». */
function formatRemainingDurationFa(remainingMs: number): string {
  const ms = Math.max(0, remainingMs);
  const days = Math.floor(ms / 86400000);
  const hours = Math.floor((ms % 86400000) / 3600000);
  const minutes = Math.floor((ms % 3600000) / 60000);
  const fa = (n: number) => n.toLocaleString('fa-IR', { useGrouping: false });
  const parts: string[] = [];
  if (days > 0) parts.push(`${fa(days)} روز`);
  if (hours > 0) parts.push(`${fa(hours)} ساعت`);
  if (minutes > 0) parts.push(`${fa(minutes)} دقیقه`);
  if (parts.length === 0) return 'کمتر از ۱ دقیقه';
  return parts.join(' و ');
}

/** Locale-aware time left from an expiry timestamp. */
export function formatRemainingForLocale(
  expiresAt: string | Date,
  locale: string,
): string {
  const date = typeof expiresAt === 'string' ? new Date(expiresAt) : expiresAt;
  if (Number.isNaN(date.getTime())) return '—';
  const remainingMs = date.getTime() - Date.now();
  return locale === 'fa'
    ? formatRemainingDurationFa(remainingMs)
    : formatRemainingDurationMs(remainingMs);
}

/**
 * Expiry timestamp in the user's locale and timezone. For Persian it renders the
 * Jalali date with weekday and time, e.g. «یکشنبه، ۲۹ تیر ۱۴۰۵، ساعت ۱۹:۵۸».
 */
export function formatExpiresAtLocal(
  expiresAt: string | Date,
  locale?: string,
): string {
  const date = typeof expiresAt === 'string' ? new Date(expiresAt) : expiresAt;
  if (Number.isNaN(date.getTime())) return '—';
  if (locale === 'fa') {
    // Assemble parts explicitly so the order is «روز هفته، روز ماه سال» regardless
    // of the runtime's ICU pattern data.
    const parts = new Intl.DateTimeFormat('fa-IR-u-ca-persian', {
      weekday: 'long',
      year: 'numeric',
      month: 'long',
      day: 'numeric',
    }).formatToParts(date);
    const get = (type: Intl.DateTimeFormatPartTypes) =>
      parts.find((p) => p.type === type)?.value ?? '';
    const weekday = get('weekday');
    const dayNum = get('day');
    const month = get('month');
    const year = get('year');
    const time = new Intl.DateTimeFormat('fa-IR-u-ca-persian', {
      hour: '2-digit',
      minute: '2-digit',
      hour12: false,
    }).format(date);
    return `${weekday}، ${dayNum} ${month} ${year}، ساعت ${time}`;
  }
  return date.toLocaleString(locale || undefined, {
    dateStyle: 'medium',
    timeStyle: 'short',
  });
}