const MINUTE = 60;
const HOUR = 3600;
const DAY = 86400;
const WEEK = 604800;
const MONTH = 2592000;
const YEAR = 31536000;

export function formatDistanceToNow(isoString: string): string {
  const seconds = Math.floor(
    (Date.now() - new Date(isoString).getTime()) / 1000,
  );

  if (seconds < 5) return "just now";
  if (seconds < MINUTE) return `${seconds}s ago`;
  if (seconds < HOUR) return `${Math.floor(seconds / MINUTE)}m ago`;
  if (seconds < DAY) return `${Math.floor(seconds / HOUR)}h ago`;
  if (seconds < WEEK) return `${Math.floor(seconds / DAY)}d ago`;
  if (seconds < MONTH) return `${Math.floor(seconds / WEEK)}w ago`;
  if (seconds < YEAR) return `${Math.floor(seconds / MONTH)}mo ago`;
  return `${Math.floor(seconds / YEAR)}y ago`;
}