Temporal API

// Create dates (no time, no timezone)
const today = Temporal.Now.plainDateISO();
console.log(today.toString());  // "2024-12-14"

// From components (months are 1-12, not 0-11!)
const date = Temporal.PlainDate.from({ 
  year: 2024, 
  month: 12,   // December = 12 (not 11!)
  day: 14 
});

// From ISO string
const date2 = Temporal.PlainDate.from('2024-12-14');

// Get components
console.log(date.year);        // 2024
console.log(date.month);       // 12 (December!)
console.log(date.day);         // 14
console.log(date.dayOfWeek);   // 6 (Saturday, 1=Monday)
console.log(date.dayOfYear);   // 349

// Add/subtract (immutable!)
const tomorrow = date.add({ days: 1 });
console.log(tomorrow.toString());  // "2024-12-15"

const nextWeek = date.add({ weeks: 1 });
const nextMonth = date.add({ months: 1 });
const nextYear = date.add({ years: 1 });

// Compare dates
console.log(Temporal.PlainDate.compare(date, tomorrow));  // -1
console.log(date.equals(date2));  // true

// Current time
const now = Temporal.Now.plainTimeISO();
console.log(now.toString());  // "15:30:45.123456789"

// From components
const time = Temporal.PlainTime.from({ 
  hour: 15, 
  minute: 30, 
  second: 45 
});

// From ISO string
const time2 = Temporal.PlainTime.from('15:30:45');

// Get components
console.log(time.hour);          // 15
console.log(time.minute);        // 30
console.log(time.second);        // 45
console.log(time.millisecond);   // 0
console.log(time.microsecond);   // 0
console.log(time.nanosecond);    // 0

// Add/subtract
const later = time.add({ hours: 2, minutes: 30 });
console.log(later.toString());  // "18:00:45"

// Round to nearest hour
const rounded = time.round({ smallestUnit: 'hour' });
console.log(rounded.toString());  // "16:00:00"

// Current date and time
const now = Temporal.Now.plainDateTimeISO();
console.log(now.toString());  // "2024-12-14T15:30:45.123456789"

// From components
const dt = Temporal.PlainDateTime.from({
  year: 2024,
  month: 12,
  day: 14,
  hour: 15,
  minute: 30
});

// From ISO string
const dt2 = Temporal.PlainDateTime.from('2024-12-14T15:30:00');

// Get date and time parts
console.log(dt.toPlainDate().toString());  // "2024-12-14"
console.log(dt.toPlainTime().toString());  // "15:30:00"

// All date properties
console.log(dt.year, dt.month, dt.day);  // 2024 12 14

// All time properties
console.log(dt.hour, dt.minute, dt.second);  // 15 30 0

// Add/subtract
const later = dt.add({ days: 1, hours: 2 });
console.log(later.toString());  // "2024-12-15T17:30:00"

// With time zone
const zoned = dt.toZonedDateTime('America/New_York');
console.log(zoned.toString());

// Current date/time in specific timezone
const nyTime = Temporal.Now.zonedDateTimeISO('America/New_York');
console.log(nyTime.toString());
// "2024-12-14T05:30:00-05:00[America/New_York]"

const tokyoTime = Temporal.Now.zonedDateTimeISO('Asia/Tokyo');
console.log(tokyoTime.toString());
// "2024-12-14T19:30:00+09:00[Asia/Tokyo]"

// From components with timezone
const meeting = Temporal.ZonedDateTime.from({
  year: 2024,
  month: 12,
  day: 25,
  hour: 10,
  minute: 0,
  timeZone: 'America/Los_Angeles'
});

// Convert between timezones
const meetingInNY = meeting.withTimeZone('America/New_York');
console.log(meeting.toString());       // "10:00 PST"
console.log(meetingInNY.toString());   // "13:00 EST"

// Get timezone info
console.log(meeting.timeZoneId);  // "America/Los_Angeles"
console.log(meeting.offset);      // "-08:00"

// Instant (exact moment in time, no timezone)
const instant = meeting.toInstant();
console.log(instant.toString());  // UTC timestamp

// Create duration
const duration = Temporal.Duration.from({
  days: 2,
  hours: 5,
  minutes: 30
});

console.log(duration.toString());  // "P2DT5H30M"

// Add duration to date
const date = Temporal.PlainDate.from('2024-12-14');
const future = date.add(duration);
console.log(future.toString());  // "2024-12-16"

// Calculate difference between dates
const start = Temporal.PlainDate.from('2024-12-14');
const end = Temporal.PlainDate.from('2024-12-25');
const diff = start.until(end);

console.log(diff.days);          // 11
console.log(diff.toString());    // "P11D"

// Different units
const diffInWeeks = start.until(end, { largestUnit: 'week' });
console.log(diffInWeeks.weeks, diffInWeeks.days);  // 1 week, 4 days

// With time
const dt1 = Temporal.PlainDateTime.from('2024-12-14T10:00');
const dt2 = Temporal.PlainDateTime.from('2024-12-14T15:30');
const timeDiff = dt1.until(dt2);

console.log(timeDiff.hours);     // 5
console.log(timeDiff.minutes);   // 30

// Total in specific unit
console.log(timeDiff.total({ unit: 'minute' }));  // 330 minutes

// ISO 8601 strings
const date = Temporal.PlainDate.from('2024-12-14');
console.log(date.toString());  // "2024-12-14"

const time = Temporal.PlainTime.from('15:30:45');
console.log(time.toString());  // "15:30:45"

const dt = Temporal.PlainDateTime.from('2024-12-14T15:30:45');
console.log(dt.toString());    // "2024-12-14T15:30:45"

// With Intl.DateTimeFormat
const formatted = new Intl.DateTimeFormat('en-US', {
  dateStyle: 'full',
  timeStyle: 'short'
}).format(dt.toZonedDateTime('UTC'));

console.log(formatted);
// "Saturday, December 14, 2024 at 3:30 PM"

// toJSON for serialization
console.log(date.toJSON());  // "2024-12-14"

// Parse various formats
const date1 = Temporal.PlainDate.from('2024-12-14');
const date2 = Temporal.PlainDate.from({ year: 2024, month: 12, day: 14 });
const date3 = Temporal.PlainDate.from(date1);  // Copy

// 1. Schedule meeting across timezones
const meeting = Temporal.ZonedDateTime.from({
  year: 2024,
  month: 12,
  day: 20,
  hour: 10,
  minute: 0,
  timeZone: 'America/Los_Angeles'
});

console.log('LA:', meeting.toString());
console.log('NY:', meeting.withTimeZone('America/New_York').toString());
console.log('Tokyo:', meeting.withTimeZone('Asia/Tokyo').toString());

// 2. Days until event
const today = Temporal.Now.plainDateISO();
const christmas = Temporal.PlainDate.from('2024-12-25');
const daysUntil = today.until(christmas, { largestUnit: 'day' });
console.log(`Days until Christmas: ${daysUntil.days}`);

// 3. Age calculation
function getAge(birthDate) {
  const today = Temporal.Now.plainDateISO();
  const age = birthDate.until(today, { largestUnit: 'year' });
  return age.years;
}

const birthDate = Temporal.PlainDate.from('1990-05-15');
console.log(`Age: ${getAge(birthDate)}`);

// 4. Business days (Mon-Fri)
function addBusinessDays(date, days) {
  let result = date;
  let remaining = days;
  
  while (remaining > 0) {
    result = result.add({ days: 1 });
    // dayOfWeek: 1=Mon, 7=Sun
    if (result.dayOfWeek <= 5) {
      remaining--;
    }
  }
  
  return result;
}

const startDate = Temporal.PlainDate.from('2024-12-13'); // Friday
const deadline = addBusinessDays(startDate, 3);
console.log(deadline.toString());  // Tuesday (skip weekend)

// 5. Start/end of day
const date = Temporal.PlainDate.from('2024-12-14');
const startOfDay = date.toPlainDateTime({ hour: 0 });
const endOfDay = date.toPlainDateTime({ hour: 23, minute: 59, second: 59 });