Date & Time Validators

const isAdult = (birthDate: Date): boolean => {
  const today = new Date();
  const age = today.getFullYear() - birthDate.getFullYear();
  const m = today.getMonth() - birthDate.getMonth();
  return age > 18 || (age === 18 && m >= 0 && today.getDate() >= birthDate.getDate());
};

const isBusinessDay = (date: Date): boolean => {
  const day = date.getDay();
  return day !== 0 && day !== 6;
};

const isWeekend = (date: Date): boolean => date.getDay() === 0 || date.getDay() === 6;

const isLeapYear = (year: number): boolean => (year % 4 === 0 && year % 100 !== 0) || year % 400 === 0;

const daysBetween = (d1: Date, d2: Date): number => {
  const oneDay = 24 * 60 * 60 * 1000;
  return Math.round(Math.abs((d1.getTime() - d2.getTime()) / oneDay));
};

const isFuture = (date: Date): boolean => date.getTime() > Date.now();

const isValidDate = (d: any): boolean => d instanceof Date && !isNaN(d.getTime());

const isPast = (date: Date): boolean => date.getTime() < Date.now();

const isSameDay = (d1: Date, d2: Date): boolean => d1.toDateString() === d2.toDateString();

const formatDate = (date: Date, locale = 'en-US'): string => 
  date.toLocaleDateString(locale, { year: 'numeric', month: 'long', day: 'numeric' });

const getAge = (birthDate: Date): number => {
  const today = new Date();
  let age = today.getFullYear() - birthDate.getFullYear();
  const m = today.getMonth() - birthDate.getMonth();
  if (m < 0 || (m === 0 && today.getDate() < birthDate.getDate())) age--;
  return age;
};

const timeAgo = (date: Date): string => {
  const seconds = Math.floor((Date.now() - date.getTime()) / 1000);
  const intervals = { year: 31536000, month: 2592000, week: 604800, day: 86400, hour: 3600, minute: 60 };
  for (const [unit, sec] of Object.entries(intervals)) {
    const interval = Math.floor(seconds / sec);
    if (interval >= 1) return `${interval} ${unit}${interval > 1 ? 's' : ''} ago`;
  }
  return 'just now';
};

const isValid = (s: string): boolean => /^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}(\.\d+)?(Z|[+-]\d{2}:\d{2})$/.test(s);

const isValid = (s: string): boolean => /^\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12]\d|3[01])$/.test(s);

const isValid = (s: string): boolean => /^([01]?[0-9]|2[0-3]):[0-5][0-9](:[0-5][0-9])?$/.test(s);

const isValid = (s: string): boolean => /^(0?[1-9]|1[0-2]):[0-5][0-9]\s?(AM|PM|am|pm)$/.test(s);

const isValid = (s: string): boolean => /^(0[1-9]|[12]\d|3[01])\/(0[1-9]|1[0-2])\/\d{4}$/.test(s);

const isValid = (s: string): boolean => /^(0[1-9]|1[0-2])\/(0[1-9]|[12]\d|3[01])\/\d{4}$/.test(s);

const isValid = (s: string): boolean => /^[+-](0[0-9]|1[0-4]):[0-5][0-9]$/.test(s);

const isValid = (s: string): boolean => /^\d{10,13}$/.test(s);