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diff --git a/apps/dav/lib/CalDAV/TimeZoneFactory.php b/apps/dav/lib/CalDAV/TimeZoneFactory.php
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+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\DAV\CalDAV;
+
+use DateTimeZone;
+
+/**
+ * Class to generate DateTimeZone object with automated Microsoft and IANA handling
+ *
+ * @since 31.0.0
+ */
+class TimeZoneFactory {
+
+	/**
+	 * conversion table of Microsoft time zones to IANA time zones
+	 *
+	 * @var array<string,string> MS2IANA
+	 */
+	private const MS2IANA = [
+		'AUS Central Standard Time' => 'Australia/Darwin',
+		'Aus Central W. Standard Time' => 'Australia/Eucla',
+		'AUS Eastern Standard Time' => 'Australia/Sydney',
+		'Afghanistan Standard Time' => 'Asia/Kabul',
+		'Alaskan Standard Time' => 'America/Anchorage',
+		'Aleutian Standard Time' => 'America/Adak',
+		'Altai Standard Time' => 'Asia/Barnaul',
+		'Arab Standard Time' => 'Asia/Riyadh',
+		'Arabian Standard Time' => 'Asia/Dubai',
+		'Arabic Standard Time' => 'Asia/Baghdad',
+		'Argentina Standard Time' => 'America/Buenos_Aires',
+		'Astrakhan Standard Time' => 'Europe/Astrakhan',
+		'Atlantic Standard Time' => 'America/Halifax',
+		'Azerbaijan Standard Time' => 'Asia/Baku',
+		'Azores Standard Time' => 'Atlantic/Azores',
+		'Bahia Standard Time' => 'America/Bahia',
+		'Bangladesh Standard Time' => 'Asia/Dhaka',
+		'Belarus Standard Time' => 'Europe/Minsk',
+		'Bougainville Standard Time' => 'Pacific/Bougainville',
+		'Cape Verde Standard Time' => 'Atlantic/Cape_Verde',
+		'Canada Central Standard Time' => 'America/Regina',
+		'Caucasus Standard Time' => 'Asia/Yerevan',
+		'Cen. Australia Standard Time' => 'Australia/Adelaide',
+		'Central America Standard Time' => 'America/Guatemala',
+		'Central Asia Standard Time' => 'Asia/Almaty',
+		'Central Brazilian Standard Time' => 'America/Cuiaba',
+		'Central Europe Standard Time' => 'Europe/Budapest',
+		'Central European Standard Time' => 'Europe/Warsaw',
+		'Central Pacific Standard Time' => 'Pacific/Guadalcanal',
+		'Central Standard Time' => 'America/Chicago',
+		'Central Standard Time (Mexico)' => 'America/Mexico_City',
+		'Chatham Islands Standard Time' => 'Pacific/Chatham',
+		'China Standard Time' => 'Asia/Shanghai',
+		'Coordinated Universal Time' => 'UTC',
+		'Cuba Standard Time' => 'America/Havana',
+		'Dateline Standard Time' => 'Etc/GMT+12',
+		'E. Africa Standard Time' => 'Africa/Nairobi',
+		'E. Australia Standard Time' => 'Australia/Brisbane',
+		'E. Europe Standard Time' => 'Europe/Chisinau',
+		'E. South America Standard Time' => 'America/Sao_Paulo',
+		'Easter Island Standard Time' => 'Pacific/Easter',
+		'Eastern Standard Time' => 'America/Toronto',
+		'Eastern Standard Time (Mexico)' => 'America/Cancun',
+		'Egypt Standard Time' => 'Africa/Cairo',
+		'Ekaterinburg Standard Time' => 'Asia/Yekaterinburg',
+		'FLE Standard Time' => 'Europe/Kiev',
+		'Fiji Standard Time' => 'Pacific/Fiji',
+		'GMT Standard Time' => 'Europe/London',
+		'GTB Standard Time' => 'Europe/Bucharest',
+		'Georgian Standard Time' => 'Asia/Tbilisi',
+		'Greenland Standard Time' => 'America/Godthab',
+		'Greenland (Danmarkshavn)' => 'America/Godthab',
+		'Greenwich Standard Time' => 'Atlantic/Reykjavik',
+		'Haiti Standard Time' => 'America/Port-au-Prince',
+		'Hawaiian Standard Time' => 'Pacific/Honolulu',
+		'India Standard Time' => 'Asia/Kolkata',
+		'Iran Standard Time' => 'Asia/Tehran',
+		'Israel Standard Time' => 'Asia/Jerusalem',
+		'Jordan Standard Time' => 'Asia/Amman',
+		'Kaliningrad Standard Time' => 'Europe/Kaliningrad',
+		'Kamchatka Standard Time' => 'Asia/Kamchatka',
+		'Korea Standard Time' => 'Asia/Seoul',
+		'Libya Standard Time' => 'Africa/Tripoli',
+		'Line Islands Standard Time' => 'Pacific/Kiritimati',
+		'Lord Howe Standard Time' => 'Australia/Lord_Howe',
+		'Magadan Standard Time' => 'Asia/Magadan',
+		'Magallanes Standard Time' => 'America/Punta_Arenas',
+		'Malaysia Standard Time' => 'Asia/Kuala_Lumpur',
+		'Marquesas Standard Time' => 'Pacific/Marquesas',
+		'Mauritius Standard Time' => 'Indian/Mauritius',
+		'Mid-Atlantic Standard Time' => 'Atlantic/South_Georgia',
+		'Middle East Standard Time' => 'Asia/Beirut',
+		'Montevideo Standard Time' => 'America/Montevideo',
+		'Morocco Standard Time' => 'Africa/Casablanca',
+		'Mountain Standard Time' => 'America/Denver',
+		'Mountain Standard Time (Mexico)' => 'America/Chihuahua',
+		'Myanmar Standard Time' => 'Asia/Rangoon',
+		'N. Central Asia Standard Time' => 'Asia/Novosibirsk',
+		'Namibia Standard Time' => 'Africa/Windhoek',
+		'Nepal Standard Time' => 'Asia/Kathmandu',
+		'New Zealand Standard Time' => 'Pacific/Auckland',
+		'Newfoundland Standard Time' => 'America/St_Johns',
+		'Norfolk Standard Time' => 'Pacific/Norfolk',
+		'North Asia East Standard Time' => 'Asia/Irkutsk',
+		'North Asia Standard Time' => 'Asia/Krasnoyarsk',
+		'North Korea Standard Time' => 'Asia/Pyongyang',
+		'Omsk Standard Time' => 'Asia/Omsk',
+		'Pacific SA Standard Time' => 'America/Santiago',
+		'Pacific Standard Time' => 'America/Los_Angeles',
+		'Pacific Standard Time (Mexico)' => 'America/Tijuana',
+		'Pakistan Standard Time' => 'Asia/Karachi',
+		'Paraguay Standard Time' => 'America/Asuncion',
+		'Qyzylorda Standard Time' => 'Asia/Qyzylorda',
+		'Romance Standard Time' => 'Europe/Paris',
+		'Russian Standard Time' => 'Europe/Moscow',
+		'Russia Time Zone 10' => 'Asia/Srednekolymsk',
+		'Russia Time Zone 3' => 'Europe/Samara',
+		'SA Eastern Standard Time' => 'America/Cayenne',
+		'SA Pacific Standard Time' => 'America/Bogota',
+		'SA Western Standard Time' => 'America/La_Paz',
+		'SE Asia Standard Time' => 'Asia/Bangkok',
+		'Saint Pierre Standard Time' => 'America/Miquelon',
+		'Sakhalin Standard Time' => 'Asia/Sakhalin',
+		'Samoa Standard Time' => 'Pacific/Apia',
+		'Sao Tome Standard Time' => 'Africa/Sao_Tome',
+		'Saratov Standard Time' => 'Europe/Saratov',
+		'Singapore Standard Time' => 'Asia/Singapore',
+		'South Africa Standard Time' => 'Africa/Johannesburg',
+		'South Sudan Standard Time' => 'Africa/Juba',
+		'Sri Lanka Standard Time' => 'Asia/Colombo',
+		'Sudan Standard Time' => 'Africa/Khartoum',
+		'Syria Standard Time' => 'Asia/Damascus',
+		'Taipei Standard Time' => 'Asia/Taipei',
+		'Tasmania Standard Time' => 'Australia/Hobart',
+		'Tocantins Standard Time' => 'America/Araguaina',
+		'Tokyo Standard Time' => 'Asia/Tokyo',
+		'Tomsk Standard Time' => 'Asia/Tomsk',
+		'Tonga Standard Time' => 'Pacific/Tongatapu',
+		'Transbaikal Standard Time' => 'Asia/Chita',
+		'Turkey Standard Time' => 'Europe/Istanbul',
+		'Turks And Caicos Standard Time' => 'America/Grand_Turk',
+		'US Eastern Standard Time' => 'America/Indianapolis',
+		'US Mountain Standard Time' => 'America/Phoenix',
+		'UTC' => 'Etc/GMT',
+		'UTC+13' => 'Etc/GMT-13',
+		'UTC+12' => 'Etc/GMT-12',
+		'UTC-02' => 'Etc/GMT+2',
+		'UTC-09' => 'Etc/GMT+9',
+		'UTC-11' => 'Etc/GMT+11',
+		'Ulaanbaatar Standard Time' => 'Asia/Ulaanbaatar',
+		'Venezuela Standard Time' => 'America/Caracas',
+		'Vladivostok Standard Time' => 'Asia/Vladivostok',
+		'Volgograd Standard Time' => 'Europe/Volgograd',
+		'W. Australia Standard Time' => 'Australia/Perth',
+		'W. Central Africa Standard Time' => 'Africa/Lagos',
+		'W. Europe Standard Time' => 'Europe/Berlin',
+		'W. Mongolia Standard Time' => 'Asia/Hovd',
+		'West Asia Standard Time' => 'Asia/Tashkent',
+		'West Bank Standard Time' => 'Asia/Hebron',
+		'West Pacific Standard Time' => 'Pacific/Port_Moresby',
+		'West Samoa Standard Time' => 'Pacific/Apia',
+		'Yakutsk Standard Time' => 'Asia/Yakutsk',
+		'Yukon Standard Time' => 'America/Whitehorse',
+		'Yekaterinburg Standard Time' => 'Asia/Yekaterinburg',
+	];
+
+	/**
+	 * Determines if given time zone name is a Microsoft time zone
+	 *
+	 * @since 31.0.0
+	 *
+	 * @param string $name time zone name
+	 *
+	 * @return bool
+	 */
+	public static function isMS(string $name): bool {
+		return isset(self::MS2IANA[$name]);
+	}
+
+	/**
+	 * Converts Microsoft time zone name to IANA time zone name
+	 *
+	 * @since 31.0.0
+	 *
+	 * @param string $name microsoft time zone
+	 *
+	 * @return string|null valid IANA time zone name on success, or null on failure
+	 */
+	public static function toIANA(string $name): ?string {
+		return isset(self::MS2IANA[$name]) ? self::MS2IANA[$name] : null;
+	}
+
+	/**
+	 * Generates DateTimeZone object for given time zone name
+	 *
+	 * @since 31.0.0
+	 *
+	 * @param string $name time zone name
+	 *
+	 * @return DateTimeZone|null
+	 */
+	public function fromName(string $name): ?DateTimeZone {
+		// if zone name is MS convert to IANA, otherwise just assume the zone is IANA
+		$zone = @timezone_open(self::toIANA($name) ?? $name);
+		return ($zone instanceof DateTimeZone) ? $zone : null;
+	}
+}