1<?php
2
3namespace Sabre\VObject;
4
5/**
6 * Time zone name translation
7 *
8 * This file translates well-known time zone names into "Olson database" time zone names.
9 *
10 * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
11 * @author Frank Edelhaeuser (fedel@users.sourceforge.net)
12 * @author Evert Pot (http://evertpot.com/)
13 * @license http://sabre.io/license/ Modified BSD License
14 */
15class TimeZoneUtil {
16
17    public static $map = null;
18
19    /**
20     * List of microsoft exchange timezone ids.
21     *
22     * Source: http://msdn.microsoft.com/en-us/library/aa563018(loband).aspx
23     */
24    public static $microsoftExchangeMap = array(
25        0  => 'UTC',
26        31 => 'Africa/Casablanca',
27
28        // Insanely, id #2 is used for both Europe/Lisbon, and Europe/Sarajevo.
29        // I'm not even kidding.. We handle this special case in the
30        // getTimeZone method.
31        2  => 'Europe/Lisbon',
32        1  => 'Europe/London',
33        4  => 'Europe/Berlin',
34        6  => 'Europe/Prague',
35        3  => 'Europe/Paris',
36        69 => 'Africa/Luanda', // This was a best guess
37        7  => 'Europe/Athens',
38        5  => 'Europe/Bucharest',
39        49 => 'Africa/Cairo',
40        50 => 'Africa/Harare',
41        59 => 'Europe/Helsinki',
42        27 => 'Asia/Jerusalem',
43        26 => 'Asia/Baghdad',
44        74 => 'Asia/Kuwait',
45        51 => 'Europe/Moscow',
46        56 => 'Africa/Nairobi',
47        25 => 'Asia/Tehran',
48        24 => 'Asia/Muscat', // Best guess
49        54 => 'Asia/Baku',
50        48 => 'Asia/Kabul',
51        58 => 'Asia/Yekaterinburg',
52        47 => 'Asia/Karachi',
53        23 => 'Asia/Calcutta',
54        62 => 'Asia/Kathmandu',
55        46 => 'Asia/Almaty',
56        71 => 'Asia/Dhaka',
57        66 => 'Asia/Colombo',
58        61 => 'Asia/Rangoon',
59        22 => 'Asia/Bangkok',
60        64 => 'Asia/Krasnoyarsk',
61        45 => 'Asia/Shanghai',
62        63 => 'Asia/Irkutsk',
63        21 => 'Asia/Singapore',
64        73 => 'Australia/Perth',
65        75 => 'Asia/Taipei',
66        20 => 'Asia/Tokyo',
67        72 => 'Asia/Seoul',
68        70 => 'Asia/Yakutsk',
69        19 => 'Australia/Adelaide',
70        44 => 'Australia/Darwin',
71        18 => 'Australia/Brisbane',
72        76 => 'Australia/Sydney',
73        43 => 'Pacific/Guam',
74        42 => 'Australia/Hobart',
75        68 => 'Asia/Vladivostok',
76        41 => 'Asia/Magadan',
77        17 => 'Pacific/Auckland',
78        40 => 'Pacific/Fiji',
79        67 => 'Pacific/Tongatapu',
80        29 => 'Atlantic/Azores',
81        53 => 'Atlantic/Cape_Verde',
82        30 => 'America/Noronha',
83         8 => 'America/Sao_Paulo', // Best guess
84        32 => 'America/Argentina/Buenos_Aires',
85        60 => 'America/Godthab',
86        28 => 'America/St_Johns',
87         9 => 'America/Halifax',
88        33 => 'America/Caracas',
89        65 => 'America/Santiago',
90        35 => 'America/Bogota',
91        10 => 'America/New_York',
92        34 => 'America/Indiana/Indianapolis',
93        55 => 'America/Guatemala',
94        11 => 'America/Chicago',
95        37 => 'America/Mexico_City',
96        36 => 'America/Edmonton',
97        38 => 'America/Phoenix',
98        12 => 'America/Denver', // Best guess
99        13 => 'America/Los_Angeles', // Best guess
100        14 => 'America/Anchorage',
101        15 => 'Pacific/Honolulu',
102        16 => 'Pacific/Midway',
103        39 => 'Pacific/Kwajalein',
104    );
105
106    /**
107     * This method will try to find out the correct timezone for an iCalendar
108     * date-time value.
109     *
110     * You must pass the contents of the TZID parameter, as well as the full
111     * calendar.
112     *
113     * If the lookup fails, this method will return the default PHP timezone
114     * (as configured using date_default_timezone_set, or the date.timezone ini
115     * setting).
116     *
117     * Alternatively, if $failIfUncertain is set to true, it will throw an
118     * exception if we cannot accurately determine the timezone.
119     *
120     * @param string $tzid
121     * @param Sabre\VObject\Component $vcalendar
122     * @return DateTimeZone
123     */
124    static public function getTimeZone($tzid, Component $vcalendar = null, $failIfUncertain = false) {
125
126        // First we will just see if the tzid is a support timezone identifier.
127        //
128        // The only exception is if the timezone starts with (. This is to
129        // handle cases where certain microsoft products generate timezone
130        // identifiers that for instance look like:
131        //
132        // (GMT+01.00) Sarajevo/Warsaw/Zagreb
133        //
134        // Since PHP 5.5.10, the first bit will be used as the timezone and
135        // this method will return just GMT+01:00. This is wrong, because it
136        // doesn't take DST into account.
137        if ($tzid[0]!=='(') {
138
139            // PHP has a bug that logs PHP warnings even it shouldn't:
140            // https://bugs.php.net/bug.php?id=67881
141            //
142            // That's why we're checking if we'll be able to successfull instantiate
143            // \DateTimeZone() before doing so. Otherwise we could simply instantiate
144            // and catch the exception.
145            $tzIdentifiers = \DateTimeZone::listIdentifiers();
146
147            try {
148                if (
149                    (in_array($tzid, $tzIdentifiers)) ||
150                    (preg_match('/^GMT(\+|-)([0-9]{4})$/', $tzid, $matches)) ||
151                    (in_array($tzid, self::getIdentifiersBC()))
152                ) {
153                    return new \DateTimeZone($tzid);
154                }
155            } catch(\Exception $e) {
156            }
157
158        }
159
160        self::loadTzMaps();
161
162        // Next, we check if the tzid is somewhere in our tzid map.
163        if (isset(self::$map[$tzid])) {
164            return new \DateTimeZone(self::$map[$tzid]);
165        }
166
167        // Maybe the author was hyper-lazy and just included an offset. We
168        // support it, but we aren't happy about it.
169        if (preg_match('/^GMT(\+|-)([0-9]{4})$/', $tzid, $matches)) {
170
171            // Note that the path in the source will never be taken from PHP 5.5.10
172            // onwards. PHP 5.5.10 supports the "GMT+0100" style of format, so it
173            // already gets returned early in this function. Once we drop support
174            // for versions under PHP 5.5.10, this bit can be taken out of the
175            // source.
176            // @codeCoverageIgnoreStart
177            return new \DateTimeZone('Etc/GMT' . $matches[1] . ltrim(substr($matches[2],0,2),'0'));
178            // @codeCoverageIgnoreEnd
179        }
180
181        if ($vcalendar) {
182
183            // If that didn't work, we will scan VTIMEZONE objects
184            foreach($vcalendar->select('VTIMEZONE') as $vtimezone) {
185
186                if ((string)$vtimezone->TZID === $tzid) {
187
188                    // Some clients add 'X-LIC-LOCATION' with the olson name.
189                    if (isset($vtimezone->{'X-LIC-LOCATION'})) {
190
191                        $lic = (string)$vtimezone->{'X-LIC-LOCATION'};
192
193                        // Libical generators may specify strings like
194                        // "SystemV/EST5EDT". For those we must remove the
195                        // SystemV part.
196                        if (substr($lic,0,8)==='SystemV/') {
197                            $lic = substr($lic,8);
198                        }
199
200                        return self::getTimeZone($lic, null, $failIfUncertain);
201
202                    }
203                    // Microsoft may add a magic number, which we also have an
204                    // answer for.
205                    if (isset($vtimezone->{'X-MICROSOFT-CDO-TZID'})) {
206                        $cdoId = (int)$vtimezone->{'X-MICROSOFT-CDO-TZID'}->getValue();
207
208                        // 2 can mean both Europe/Lisbon and Europe/Sarajevo.
209                        if ($cdoId===2 && strpos((string)$vtimezone->TZID, 'Sarajevo')!==false) {
210                            return new \DateTimeZone('Europe/Sarajevo');
211                        }
212
213                        if (isset(self::$microsoftExchangeMap[$cdoId])) {
214                            return new \DateTimeZone(self::$microsoftExchangeMap[$cdoId]);
215                        }
216                    }
217
218                }
219
220            }
221
222        }
223
224        if ($failIfUncertain) {
225            throw new \InvalidArgumentException('We were unable to determine the correct PHP timezone for tzid: ' . $tzid);
226        }
227
228        // If we got all the way here, we default to UTC.
229        return new \DateTimeZone(date_default_timezone_get());
230
231    }
232
233    /**
234     * This method will load in all the tz mapping information, if it's not yet
235     * done.
236     */
237    static public function loadTzMaps() {
238
239        if (!is_null(self::$map)) return;
240
241        self::$map = array_merge(
242            include __DIR__ .  '/timezonedata/windowszones.php',
243            include __DIR__ .  '/timezonedata/lotuszones.php',
244            include __DIR__ .  '/timezonedata/exchangezones.php',
245            include __DIR__ .  '/timezonedata/php-workaround.php'
246        );
247
248    }
249
250    /**
251     * This method returns an array of timezone identifiers, that are supported
252     * by DateTimeZone(), but not returned by DateTimeZone::listIdentifiers()
253     *
254     * We're not using DateTimeZone::listIdentifiers(DateTimeZone::ALL_WITH_BC) because:
255     * - It's not supported by some PHP versions as well as HHVM.
256     * - It also returns identifiers, that are invalid values for new DateTimeZone() on some PHP versions.
257     * (See timezonedata/php-bc.php and timezonedata php-workaround.php)
258     *
259     * @return array
260     */
261    static public function getIdentifiersBC() {
262        return include __DIR__ .  '/timezonedata/php-bc.php';
263    }
264
265}
266