// References:
// Some mobile operating systems support old timezone names that must be mapped to the new ones.
// - https://en.wikipedia.org/wiki/List_of_tz_database_time_zones
// - https://ftp.iana.org/tz/tzdb-2024a/backward
const backwardsMap = new Map([
  ['Australia/ACT', 'Australia/Sydney'],
  ['Australia/Canberra', 'Australia/Sydney'],
  ['Australia/LHI', 'Australia/Lord_Howe'],
  ['Australia/NSW', 'Australia/Sydney'],
  ['Australia/North', 'Australia/Darwin'],
  ['Australia/Queensland', 'Australia/Brisbane'],
  ['Australia/South', 'Australia/Adelaide'],
  ['Australia/Tasmania', 'Australia/Hobart'],
  ['Australia/Victoria', 'Australia/Melbourne'],
  ['Australia/West', 'Australia/Perth'],
  ['Australia/Yancowinna', 'Australia/Broken_Hill'],
  ['Brazil/Acre', 'America/Rio_Branco'],
  ['America/Porto_Acre', 'America/Rio_Branco'],
  ['Brazil/DeNoronha', 'America/Noronha'],
  ['Brazil/East', 'America/Sao_Paulo'],
  ['Brazil/West', 'America/Manaus'],
  ['Canada/Atlantic', 'America/Halifax'],
  ['Canada/Central', 'America/Winnipeg'],
  ['Canada/Eastern', 'America/Toronto'],
  ['Canada/Mountain', 'America/Edmonton'],
  ['Canada/Newfoundland', 'America/St_Johns'],
  ['Canada/Pacific', 'America/Vancouver'],
  ['Canada/Saskatchewan', 'America/Regina'],
  ['Canada/Yukon', 'America/Whitehorse'],
  ['Chile/Continental', 'America/Santiago'],
  ['Chile/EasterIsland', 'Pacific/Easter'],
  ['Cuba', 'America/Havana'],
  ['Eire', 'Europe/Dublin'],
  ['Etc/GMT+0', 'Etc/GMT'],
  ['Etc/GMT-0', 'Etc/GMT'],
  ['Etc/GMT0', 'Etc/GMT'],
  ['Etc/Greenwich', 'Etc/GMT'],
  ['Etc/GMT+0', 'Etc/UTC'],
  ['Etc/GMT-0', 'Etc/UTC'],
  ['Etc/GMT0', 'Etc/UTC'],
  ['Etc/Greenwich', 'Etc/UTC'],
  ['Etc/UCT', 'Etc/UTC'],
  ['Etc/Universal', 'Etc/UTC'],
  ['Etc/Zulu', 'Etc/UTC'],
  ['GB', 'Europe/London'],
  ['GB-Eire', 'Europe/London'],
  ['Etc/GMT+0', 'Etc/GMT'],
  ['Etc/GMT-0', 'Etc/GMT'],
  ['Etc/GMT0', 'Etc/GMT'],
  ['Etc/Greenwich', 'Etc/GMT'],
  ['Hongkong', 'Asia/Hong_Kong'],
  ['Iran', 'Asia/Tehran'],
  ['Israel', 'Asia/Jerusalem'],
  ['Jamaica', 'America/Jamaica'],
  ['Japan', 'Asia/Tokyo'],
  ['Kwajalein', 'Pacific/Kwajalein'],
  ['Libya', 'Africa/Tripoli'],
  ['Mexico/BajaNorte', 'America/Tijuana'],
  ['Mexico/BajaSur', 'America/Mazatlan'],
  ['Mexico/General', 'America/Mexico_City'],
  ['NZ', 'Pacific/Auckland'],
  ['NZ-CHAT', 'Pacific/Chatham'],
  ['Navajo', 'America/Denver'],
  ['America/Shiprock', 'America/Denver'],
  ['PRC', 'Asia/Shanghai'],
  ['Poland', 'Europe/Warsaw'],
  ['Portugal', 'Europe/Lisbon'],
  ['ROC', 'Asia/Taipei'],
  ['ROK', 'Asia/Seoul'],
  ['Singapore', 'Asia/Singapore'],
  ['Turkey', 'Europe/Istanbul'],
  ['UCT', 'Etc/UTC'],
  ['US/Alaska', 'America/Anchorage'],
  ['US/Aleutian', 'America/Adak'],
  ['US/Arizona', 'America/Phoenix'],
  ['US/Central', 'America/Chicago'],
  ['US/East-Indiana', 'America/Indiana/Indianapolis'],
  ['US/Eastern', 'America/New_York'],
  ['US/Hawaii', 'Pacific/Honolulu'],
  ['US/Indiana-Starke', 'America/Indiana/Knox'],
  ['US/Michigan', 'America/Detroit'],
  ['US/Mountain', 'America/Denver'],
  ['US/Pacific', 'America/Los_Angeles'],
  ['US/Samoa', 'Pacific/Pago_Pago'],
  ['UTC', 'Etc/UTC'],
  ['Universal', 'Etc/UTC'],
  ['W-SU', 'Europe/Moscow'],
  ['Zulu', 'Etc/UTC'],
  ['America/Buenos_Aires', 'America/Argentina/Buenos_Aires'],
  ['America/Catamarca', 'America/Argentina/Catamarca'],
  ['America/Cordoba', 'America/Argentina/Cordoba'],
  ['America/Indianapolis', 'America/Indiana/Indianapolis'],
  ['America/Jujuy', 'America/Argentina/Jujuy'],
  ['America/Knox_IN', 'America/Indiana/Knox'],
  ['America/Louisville', 'America/Kentucky/Louisville'],
  ['America/Mendoza', 'America/Argentina/Mendoza'],
  ['America/Virgin', 'America/Puerto_Rico'],
  ['America/St_Thomas', 'America/Puerto_Rico'],
  ['Pacific/Samoa', 'Pacific/Pago_Pago'],
  ['Africa/Accra', 'Africa/Abidjan'],
  ['Africa/Addis_Ababa', 'Africa/Nairobi'],
  ['Africa/Asmara', 'Africa/Nairobi'],
  ['Africa/Bamako', 'Africa/Abidjan'],
  ['Africa/Bangui', 'Africa/Lagos'],
  ['Africa/Banjul', 'Africa/Abidjan'],
  ['Africa/Blantyre', 'Africa/Maputo'],
  ['Africa/Brazzaville', 'Africa/Lagos'],
  ['Africa/Bujumbura', 'Africa/Maputo'],
  ['Africa/Conakry', 'Africa/Abidjan'],
  ['Africa/Dakar', 'Africa/Abidjan'],
  ['Africa/Dar_es_Salaam', 'Africa/Nairobi'],
  ['Africa/Djibouti', 'Africa/Nairobi'],
  ['Africa/Douala', 'Africa/Lagos'],
  ['Africa/Freetown', 'Africa/Abidjan'],
  ['Africa/Gaborone', 'Africa/Maputo'],
  ['Africa/Harare', 'Africa/Maputo'],
  ['Africa/Kampala', 'Africa/Nairobi'],
  ['Africa/Kigali', 'Africa/Maputo'],
  ['Africa/Kinshasa', 'Africa/Lagos'],
  ['Africa/Libreville', 'Africa/Lagos'],
  ['Africa/Lome', 'Africa/Abidjan'],
  ['Africa/Luanda', 'Africa/Lagos'],
  ['Africa/Lubumbashi', 'Africa/Maputo'],
  ['Africa/Lusaka', 'Africa/Maputo'],
  ['Africa/Malabo', 'Africa/Lagos'],
  ['Africa/Maseru', 'Africa/Johannesburg'],
  ['Africa/Mbabane', 'Africa/Johannesburg'],
  ['Africa/Mogadishu', 'Africa/Nairobi'],
  ['Africa/Niamey', 'Africa/Lagos'],
  ['Africa/Nouakchott', 'Africa/Abidjan'],
  ['Africa/Ouagadougou', 'Africa/Abidjan'],
  ['Africa/Porto-Novo', 'Africa/Lagos'],
  ['America/Anguilla', 'America/Puerto_Rico'],
  ['America/Antigua', 'America/Puerto_Rico'],
  ['America/Aruba', 'America/Puerto_Rico'],
  ['America/Atikokan', 'America/Panama'],
  ['America/Blanc-Sablon', 'America/Puerto_Rico'],
  ['America/Cayman', 'America/Panama'],
  ['America/Creston', 'America/Phoenix'],
  ['America/Curacao', 'America/Puerto_Rico'],
  ['America/Dominica', 'America/Puerto_Rico'],
  ['America/Grenada', 'America/Puerto_Rico'],
  ['America/Guadeloupe', 'America/Puerto_Rico'],
  ['America/Kralendijk', 'America/Puerto_Rico'],
  ['America/Lower_Princes', 'America/Puerto_Rico'],
  ['America/Marigot', 'America/Puerto_Rico'],
  ['America/Montserrat', 'America/Puerto_Rico'],
  ['America/Nassau', 'America/Toronto'],
  ['America/Port_of_Spain', 'America/Puerto_Rico'],
  ['America/St_Barthelemy', 'America/Puerto_Rico'],
  ['America/St_Kitts', 'America/Puerto_Rico'],
  ['America/St_Lucia', 'America/Puerto_Rico'],
  ['America/St_Thomas', 'America/Puerto_Rico'],
  ['America/St_Vincent', 'America/Puerto_Rico'],
  ['America/Tortola', 'America/Puerto_Rico'],
  ['Antarctica/DumontDUrville', 'Pacific/Port_Moresby'],
  ['Antarctica/McMurdo', 'Pacific/Auckland'],
  ['Antarctica/Syowa', 'Antarctica/Syowa'],
  ['Arctic/Longyearbyen', 'Europe/Berlin'],
  ['Asia/Aden', 'Asia/Riyadh'],
  ['Asia/Bahrain', 'Asia/Qatar'],
  ['Asia/Brunei', 'Asia/Kuching'],
  ['Asia/Kuala_Lumpur', 'Asia/Singapore'],
  ['Asia/Kuwait', 'Asia/Riyadh'],
  ['Asia/Muscat', 'Asia/Dubai'],
  ['Asia/Phnom_Penh', 'Asia/Bangkok'],
  ['Asia/Vientiane', 'Asia/Bangkok'],
  ['Atlantic/Reykjavik', 'Africa/Abidjan'],
  ['Atlantic/St_Helena', 'Africa/Abidjan'],
  ['Europe/Amsterdam', 'Europe/Brussels'],
  ['Europe/Bratislava', 'Europe/Prague'],
  ['Europe/Busingen', 'Europe/Zurich'],
  ['Europe/Copenhagen', 'Europe/Berlin'],
  ['Europe/Guernsey', 'Europe/London'],
  ['Europe/Isle_of_Man', 'Europe/London'],
  ['Europe/Jersey', 'Europe/London'],
  ['Europe/Ljubljana', 'Europe/Belgrade'],
  ['Europe/Luxembourg', 'Europe/Brussels'],
  ['Europe/Mariehamn', 'Europe/Helsinki'],
  ['Europe/Monaco', 'Europe/Paris'],
  ['Europe/Oslo', 'Europe/Berlin'],
  ['Europe/Podgorica', 'Europe/Belgrade'],
  ['Europe/San_Marino', 'Europe/Rome'],
  ['Europe/Sarajevo', 'Europe/Belgrade'],
  ['Europe/Skopje', 'Europe/Belgrade'],
  ['Europe/Stockholm', 'Europe/Berlin'],
  ['Europe/Vaduz', 'Europe/Zurich'],
  ['Europe/Vatican', 'Europe/Rome'],
  ['Europe/Zagreb', 'Europe/Belgrade'],
  ['Indian/Antananarivo', 'Africa/Nairobi'],
  ['Indian/Christmas', 'Asia/Bangkok'],
  ['Indian/Cocos', 'Asia/Yangon'],
  ['Indian/Comoro', 'Africa/Nairobi'],
  ['Indian/Kerguelen', 'Indian/Maldives'],
  ['Indian/Mahe', 'Asia/Dubai'],
  ['Indian/Mayotte', 'Africa/Nairobi'],
  ['Indian/Reunion', 'Asia/Dubai'],
  ['Pacific/Chuuk', 'Pacific/Port_Moresby'],
  ['Pacific/Funafuti', 'Pacific/Tarawa'],
  ['Pacific/Majuro', 'Pacific/Tarawa'],
  ['Pacific/Midway', 'Pacific/Pago_Pago'],
  ['Pacific/Pohnpei', 'Pacific/Guadalcanal'],
  ['Pacific/Saipan', 'Pacific/Guam'],
  ['Pacific/Wake', 'Pacific/Tarawa'],
  ['Pacific/Wallis', 'Pacific/Tarawa'],
  ['Africa/Timbuktu', 'Africa/Abidjan'],
  ['America/Argentina/ComodRivadavia', 'America/Argentina/Catamarca'],
  ['America/Atka', 'America/Adak'],
  ['America/Coral_Harbour', 'America/Panama'],
  ['America/Ensenada', 'America/Tijuana'],
  ['America/Fort_Wayne', 'America/Indiana/Indianapolis'],
  ['America/Montreal', 'America/Toronto'],
  ['America/Nipigon', 'America/Toronto'],
  ['America/Pangnirtung', 'America/Iqaluit'],
  ['America/Porto_Acre', 'America/Rio_Branco'],
  ['America/Rainy_River', 'America/Winnipeg'],
  ['America/Rosario', 'America/Argentina/Cordoba'],
  ['America/Santa_Isabel', 'America/Tijuana'],
  ['America/Shiprock', 'America/Denver'],
  ['America/Thunder_Bay', 'America/Toronto'],
  ['America/Yellowknife', 'America/Edmonton'],
  ['Antarctica/South_Pole', 'Pacific/Auckland'],
  ['Asia/Chongqing', 'Asia/Shanghai'],
  ['Asia/Harbin', 'Asia/Shanghai'],
  ['Asia/Kashgar', 'Asia/Urumqi'],
  ['Asia/Tel_Aviv', 'Asia/Jerusalem'],
  ['Atlantic/Jan_Mayen', 'Europe/Berlin'],
  ['Australia/Canberra', 'Australia/Sydney'],
  ['Australia/Currie', 'Australia/Hobart'],
  ['Europe/Belfast', 'Europe/London'],
  ['Europe/Tiraspol', 'Europe/Chisinau'],
  ['Europe/Uzhgorod', 'Europe/Kyiv'],
  ['Europe/Zaporozhye', 'Europe/Kyiv'],
  ['Pacific/Enderbury', 'Pacific/Kanton'],
  ['Pacific/Johnston', 'Pacific/Honolulu'],
  ['Pacific/Yap', 'Pacific/Port_Moresby'],
  ['Africa/Asmera', 'Africa/Nairobi'],
  ['Africa/Asmara', 'Africa/Nairobi'],
  ['America/Godthab', 'America/Nuuk'],
  ['Asia/Ashkhabad', 'Asia/Ashgabat'],
  ['Asia/Calcutta', 'Asia/Kolkata'],
  ['Asia/Chungking', 'Asia/Shanghai'],
  ['Asia/Chongqing', 'Asia/Shanghai'],
  ['Asia/Dacca', 'Asia/Dhaka'],
  ['Asia/Istanbul', 'Europe/Istanbul'],
  ['Asia/Katmandu', 'Asia/Kathmandu'],
  ['Asia/Macao', 'Asia/Macau'],
  ['Asia/Rangoon', 'Asia/Yangon'],
  ['Asia/Saigon', 'Asia/Ho_Chi_Minh'],
  ['Asia/Thimbu', 'Asia/Thimphu'],
  ['Asia/Ujung_Pandang', 'Asia/Makassar'],
  ['Asia/Ulan_Bator', 'Asia/Ulaanbaatar'],
  ['Atlantic/Faeroe', 'Atlantic/Faroe'],
  ['Europe/Kiev', 'Europe/Kyiv'],
  ['Europe/Nicosia', 'Asia/Nicosia'],
  ['Pacific/Ponape', 'Pacific/Guadalcanal'],
  ['Pacific/Pohnpei', 'Pacific/Guadalcanal'],
  ['Pacific/Truk', 'Pacific/Port_Moresby'],
  ['Pacific/Chuuk', 'Pacific/Port_Moresby'],
])

export const formatTimezone = (timezone: string): string => {
  if (backwardsMap.has(timezone)) {
    return backwardsMap.get(timezone) as string
  }

  return timezone
}