“Time Zone” user preference

Resolves #8518

Author: brandonkelly

CHANGELOG-WIP.md

@@ -15,6 +15,7 @@
 - Entries’ “Entry type settings” and “Section settings” action menu items are now only shown for element edit screens’ primary action menus.
 - Category indexes can now have “Group” columns. ([#18553](https://github.com/craftcms/cms/discussions/18553))
 - Element slideouts now automatically refresh when the same element is updated in another tab/slideout. ([#18625](https://github.com/craftcms/cms/pull/18625))
+- Added the “Time Zone” user preference. ([#8518](https://github.com/craftcms/cms/discussions/8518))
 
 ### Administration
 - Time fields’ “Max Time” settings can now be set to an earlier time than “Min Time”, for overnight time ranges. ([#18575](https://github.com/craftcms/cms/pull/18575))

src/base/ApplicationTrait.php

@@ -1585,11 +1585,13 @@ private function _preInit(): void
         $this->getRequest();
         $this->getLog();
 
+        $isCpRequest = $this->getRequest()->getIsCpRequest();
+
         // Set the timezone
-        $this->_setTimeZone();
+        $this->_setTimeZone($isCpRequest);
 
         // Set the language
-        $this->updateTargetLanguage();
+        $this->updateTargetLanguage($isCpRequest);
 
         // Register the variable dumper
         VarDumper::setHandler(function($var) {
@@ -1644,9 +1646,24 @@ private function _postInit(): void
     /**
      * Sets the system timezone.
      */
-    private function _setTimeZone(): void
+    private function _setTimeZone(bool $useUserTz): void
     {
-        $timeZone = $this->getConfig()->getGeneral()->timezone ?? $this->getProjectConfig()->get('system.timeZone');
+        $timeZone = null;
+
+        if ($useUserTz) {
+            // If the user is logged in *and* has a preferred time zone, use that
+            // (don't actually try to fetch the user, as plugins haven't been loaded yet)
+            /** @var UserSession $user */
+            $user = $this->getUser();
+            $id = Session::get($user->idParam);
+            if ($id) {
+                $timeZone = $this->getUsers()->getUserPreference($id, 'timeZone');
+            }
+        }
+
+        if (!$timeZone) {
+            $timeZone = $this->getConfig()->getGeneral()->timezone ?? $this->getProjectConfig()->get('system.timeZone');
+        }
 
         if ($timeZone) {
             $this->setTimeZone(App::parseEnv($timeZone));

src/controllers/UsersController.php

@@ -51,6 +51,7 @@
 use craft\web\UploadedFile;
 use craft\web\View;
 use DateTime;
+use DateTimeZone;
 use Throwable;
 use yii\base\Exception;
 use yii\base\InvalidArgumentException;
@@ -1361,10 +1362,17 @@ public function actionPreferences(): Response
             $userLocale = Craft::$app->getConfig()->getGeneral()->defaultCpLocale;
         }
 
+        // time zone
+        $timeZone = new DateTimeZone(Craft::$app->getTimeZone());
+        $offsetDate = (new DateTime())->setTimezone(new DateTimeZone('UTC'));
+        $transition = $timeZone->getTransitions($offsetDate->getTimestamp(), $offsetDate->getTimestamp());
+        $timeZoneAbbr = $transition[0]['abbr'];
+
         $response->action('users/save-preferences');
         $response->contentTemplate('users/_preferences', compact(
             'userLanguage',
             'userLocale',
+            'timeZoneAbbr',
         ));
 
         return $response;
@@ -1385,10 +1393,15 @@ public function actionSavePreferences(): Response
         if ($preferredLocale === '__blank__') {
             $preferredLocale = null;
         }
+        $timeZone = $this->request->getBodyParam('timeZone', $user->getPreference('timezone')) ?: null;
+        if ($timeZone === '__blank__') {
+            $timeZone = null;
+        }
         $preferences = [
             'language' => $this->request->getBodyParam('preferredLanguage', $user->getPreference('language')),
             'locale' => $preferredLocale,
             'weekStartDay' => $this->request->getBodyParam('weekStartDay', $user->getPreference('weekStartDay')),
+            'timeZone' => $timeZone,
             'useShapes' => (bool)$this->request->getBodyParam('useShapes', $user->getPreference('useShapes')),
             'underlineLinks' => (bool)$this->request->getBodyParam('underlineLinks', $user->getPreference('underlineLinks')),
             'disableAutofocus' => $this->request->getBodyParam('disableAutofocus', $user->getPreference('disableAutofocus')),

src/templates/_includes/forms/timeZone.twig

@@ -1,7 +1,7 @@
 {% set id = id ?? "timezone#{random()}" %}
 
 {% include '_includes/forms/selectize' with {
-    options: craft.cp.getTimeZoneOptions(offsetDate ?? null),
+    options: options ?? craft.cp.getTimeZoneOptions(offsetDate ?? null),
     inputAttributes: {
         aria: {
             label: 'Time Zone'|t('app'),

src/templates/users/_preferences.twig

@@ -33,6 +33,17 @@
     options: craft.app.locale.getWeekDayNames(),
     value: currentUser.getPreference('weekStartDay', craft.app.config.general.defaultWeekStartDay)
   }) }}
+
+  {{ forms.timeZoneField({
+    label: 'Time Zone'|t('app'),
+    id: 'time-zone',
+    name: 'timeZone',
+    options: [
+      {label: 'System time zone ({abbr})'|t('app', {abbr: timeZoneAbbr}), value: '__blank__'},
+      ...craft.cp.getTimeZoneOptions(offsetDate ?? null),
+    ],
+    value: currentUser.getPreference('timeZone'),
+  }) }}
 </div>
 
 <hr>

src/translations/en/app.php

@@ -1664,6 +1664,7 @@
     'System Name' => 'System Name',
     'System Report' => 'System Report',
     'System Status' => 'System Status',
+    'System time zone ({abbr})' => 'System time zone ({abbr})',
     'System' => 'System',
     'Table Columns' => 'Table Columns',
     'Table' => 'Table',