// Number formatting that fits a 280px-wide widget.

export function formatTokens(n: number): string {
  if (n >= 1_000_000) return `${(n / 1_000_000).toFixed(2)}M`;
  if (n >= 10_000) return `${(n / 1_000).toFixed(0)}k`;
  if (n >= 1_000) return `${(n / 1_000).toFixed(1)}k`;
  return n.toString();
}

export function formatPct(num: number, denom: number): string {
  if (denom <= 0) return "0%";
  const pct = Math.min(999, Math.round((num / denom) * 100));
  return `${pct}%`;
}

export function formatCountdown(seconds: number): string {
  const s = Math.max(0, Math.floor(seconds));
  const h = Math.floor(s / 3600);
  const m = Math.floor((s % 3600) / 60);
  const sec = s % 60;
  if (h > 0) return `${h}h ${m.toString().padStart(2, "0")}m`;
  return `${m.toString().padStart(2, "0")}:${sec.toString().padStart(2, "0")}`;
}

/// "2026-05-09" → "Sat" (weekday in user's local).
export function weekdayShort(date_local: string): string {
  // date_local is already a calendar day; treat it as local midnight.
  const d = new Date(`${date_local}T00:00:00`);
  return d.toLocaleDateString(undefined, { weekday: "short" });
}