import HolyTime from 'holy-time';

// Access all supported timezones
HolyTime.TimeZones;
// ['Africa/Abidjan', 'Africa/Accra', 'America/New_York', 'Asia/Tokyo', 'Europe/London', 'UTC', ...]

const currentTz = HolyTime.getTimeZone();
// 'America/New_York', 'Europe/London', etc. (depends on system settings)

const time = HolyTime.now();

// Get values in UTC
const utcHour = time.get('hour', 'UTC');
const utcDay = time.get('day', 'UTC');

// Format in UTC
time.format('YYYY-MM-DD HH:mm:ss', 'UTC');
// '2024-03-04 19:30:45'

// Start of day in UTC
const utcDayStart = time.startOf('day', 'UTC');

const time = new HolyTime(new Date('2024-03-04T14:30:00'));

// Local time (depends on system timezone)
time.format('YYYY-MM-DD HH:mm:ss');
// '2024-03-04 14:30:00' (if system is in that timezone)

// UTC time
time.format('YYYY-MM-DD HH:mm:ss', 'UTC');
// '2024-03-04 19:30:00' (if local timezone is EST, UTC-5)

const time = HolyTime.now();

// Same moment in different timezones
time.format('YYYY-MM-DD HH:mm:ss', 'America/New_York');
// '2024-03-04 14:30:00'

time.format('YYYY-MM-DD HH:mm:ss', 'Europe/London');
// '2024-03-04 19:30:00'

time.format('YYYY-MM-DD HH:mm:ss', 'Asia/Tokyo');
// '2024-03-05 04:30:00'

const time = new HolyTime(new Date('2024-03-04T23:30:00Z'));

// Hour in different timezones
time.get('hour', 'UTC');            // 23
time.get('hour', 'America/New_York'); // 18 (UTC-5)
time.get('hour', 'Asia/Tokyo');     // 8 (next day, UTC+9)

// Day can change across timezones
time.get('day', 'UTC');             // 4
time.get('day', 'Asia/Tokyo');      // 5

const time = new HolyTime(new Date('2024-03-04T14:30:00'));

// Start of day in different timezones
time.startOf('day', 'UTC');
time.startOf('day', 'America/New_York');
time.startOf('day', 'Asia/Tokyo');

// End of month in specific timezone
time.endOf('month', 'Europe/Paris');

// Start of day in New York
const nyDayStart = HolyTime.startOf(
  'day',
  new Date('2024-03-04T14:30:00'),
  'America/New_York'
);

// End of week in Tokyo
const tokyoWeekEnd = HolyTime.endOf(
  'week',
  new Date(),
  'Asia/Tokyo'
);

const time = HolyTime.now();

// Short offset
time.format('YYYY-MM-DD HH:mm:ss O', 'America/New_York');
// '2024-03-04 14:30:00 GMT-5'

// Long offset
time.format('YYYY-MM-DD HH:mm:ss OO', 'Europe/Paris');
// '2024-03-04 20:30:00 GMT+01:00'

// Timezone identifier
time.format('YYYY-MM-DD HH:mm:ss TZ', 'Asia/Tokyo');
// '2024-03-05 04:30:00 Asia/Tokyo'

// Combined
time.format('YYYY-MM-DD HH:mm:ss (TZ, OO)', 'America/Los_Angeles');
// '2024-03-04 11:30:00 (America/Los_Angeles, GMT-08:00)'

time.format('O');   // 'GMT-5' (short, omits minutes if zero)
time.format('OO');  // 'GMT-05:00' (long, always includes minutes)

// Currently supported alias
const TIMEZONE_MAP = {
  'UTC+0': 'UTC',
} as const;

const meetingTime = new HolyTime(new Date('2024-03-15T14:00:00'));

console.log('Meeting times:');
console.log('New York:', meetingTime.format('h:mm A', 'America/New_York'));
console.log('London:', meetingTime.format('h:mm A', 'Europe/London'));
console.log('Tokyo:', meetingTime.format('h:mm A', 'Asia/Tokyo'));
console.log('Sydney:', meetingTime.format('h:mm A', 'Australia/Sydney'));

function isDuringBusinessHours(time: HolyTime, timezone: TimeZone): boolean {
  const hour = time.get('hour', timezone);
  const day = time.get('day', timezone);
  
  // Monday-Friday, 9 AM - 5 PM
  const isWeekday = day >= 1 && day <= 5;
  const isBusinessHour = hour >= 9 && hour < 17;
  
  return isWeekday && isBusinessHour;
}

const now = HolyTime.now();
isDuringBusinessHours(now, 'America/New_York');
isDuringBusinessHours(now, 'Europe/London');

// Get the start of tomorrow in Tokyo time
const tokyoTomorrow = HolyTime.next('day', new Date(), 'Asia/Tokyo');

// Format it in multiple timezones
console.log('Tokyo:', tokyoTomorrow.format('YYYY-MM-DD HH:mm', 'Asia/Tokyo'));
console.log('UTC:', tokyoTomorrow.format('YYYY-MM-DD HH:mm', 'UTC'));

// Good: Explicit timezone
const dayStart = HolyTime.startOf('day', new Date(), 'America/New_York');

// Avoid: Implicit local timezone (varies by user)
const dayStart = HolyTime.startOf('day', new Date());

// Store as UTC timestamp
const timestamp = HolyTime.now().getTime();

// Display in user's timezone
const userTz = HolyTime.getTimeZone();
const displayTime = new HolyTime(timestamp).format('YYYY-MM-DD HH:mm', userTz);

// Good: IANA identifier
time.format('YYYY-MM-DD', 'America/New_York');

// Avoid: Abbreviations (ambiguous)
// 'EST' could mean different things

private static adjustToTimeZone(date: Date, timeZone?: TimeZone): Date {
  if (!timeZone) {
    return date;
  }

  const newTimeZone =
    TIMEZONE_MAP[timeZone as keyof typeof TIMEZONE_MAP] ?? timeZone;

  return new Date(date.toLocaleString('en-US', { timeZone: newTimeZone }));
}