export function formatDuration(nano: number): string {
  if (nano >= 3600000000000) { // 1 hour in nanoseconds
    return `${(nano / 3600000000000).toFixed(1)}h`;
  } else if (nano >= 60000000000) { // 1 minute
    return `${(nano / 60000000000).toFixed(1)}m`;
  } else if (nano >= 1000000000) { // 1 second
    return `${(nano / 1000000000).toFixed(1)}s`;
  } else if (nano >= 1000000) { // 1 millisecond
    return `${(nano / 1000000).toFixed(1)}ms`;
  } else if (nano >= 1000) { // 1 microsecond
    return `${(nano / 1000).toFixed(1)}μs`;
  } else {
    return `${nano.toFixed(1)}ns`;
  }
}

/** "just now", "2m ago", "3h ago", "5d ago" */
export function formatRelativeTime(msEpoch: number): string {
  const seconds = Math.max(0, (Date.now() - msEpoch) / 1000);
  if (seconds < 60) return "just now";
  if (seconds < 3600) return `${Math.floor(seconds / 60)}m ago`;
  if (seconds < 86400) return `${Math.floor(seconds / 3600)}h ago`;
  return `${Math.floor(seconds / 86400)}d ago`;
}