// Function: timeAgo
export function timeAgo(date: string): string {
  const now = new Date();
  const past = new Date(date);
  const diff = now.getTime() - past.getTime();

  const seconds = Math.floor(diff / 1000);
  const minutes = Math.floor(seconds / 60);
  const hours = Math.floor(minutes / 60);
  const days = Math.floor(hours / 24);
  const months = Math.floor(days / 30.44);
  const years = Math.floor(months / 12);

  if (years > 0) return `${years} year${years > 1 ? 's' : ''} ago`;
  if (months > 0) return `${months} month${months > 1 ? 's' : ''} ago`;
  if (days > 0) return `${days} day${days > 1 ? 's' : ''} ago`;
  if (hours > 0) return `${hours} hour${hours > 1 ? 's' : ''} ago`;
  if (minutes > 0) return `${minutes} minute${minutes > 1 ? 's' : ''} ago`;
  return `just now`;
}

// Function: getTimeDiff
export function getTimeDiff(start: Date | string, end: Date | string) {
  const s = new Date(start).getTime();
  const e = new Date(end).getTime();
  let diff = Math.abs(e - s) / 1000; // in seconds

  const days = Math.floor(diff / 86400);
  diff %= 86400;
  const hours = Math.floor(diff / 3600);
  diff %= 3600;
  const mins = Math.floor(diff / 60);
  const secs = Math.floor(diff % 60);

  return { days, hours, mins, secs };
}

// Function: formatDate
export function formatDate(date: Date | string, format: string): string {
  const d = new Date(date);
  const YYYY = d.getFullYear();
  const MM = String(d.getMonth() + 1).padStart(2, '0');
  const DD = String(d.getDate()).padStart(2, '0');

  return format
    .replace('YYYY', YYYY.toString())
    .replace('MM', MM)
    .replace('DD', DD);
}

// Function: isLeapYear
export function isLeapYear(year: number): boolean {
  return (year % 4 === 0 && year % 100 !== 0) || year % 400 === 0;
}