MOBILE-3784 time: Fix time zone usage in ion-datetime

src/addons/calendar/pages/edit-event/edit-event.html

@@ -31,7 +31,7 @@
                     <p class="item-heading" [core-mark-required]="true">{{ 'core.date' | translate }}</p>
                 </ion-label>
                 <ion-datetime formControlName="timestart" [placeholder]="'core.date' | translate" [displayFormat]="dateFormat"
-                    [max]="maxDate" [min]="minDate" display-timezone="utc">
+                    [max]="maxDate" [min]="minDate">
                 </ion-datetime>
                 <core-input-errors [control]="form.controls.timestart" [errorMessages]="errors"></core-input-errors>
             </ion-item>
@@ -156,7 +156,7 @@
                     <ion-item *ngIf="form.controls.duration.value === 1">
                         <ion-label position="stacked"></ion-label>
                         <ion-datetime formControlName="timedurationuntil" [max]="maxDate" [min]="minDate"
-                            [placeholder]="'addon.calendar.durationuntil' | translate" [displayFormat]="dateFormat" display-timezone="utc">
+                            [placeholder]="'addon.calendar.durationuntil' | translate" [displayFormat]="dateFormat">
                         </ion-datetime>
                     </ion-item>
                     <ion-item>

src/addons/calendar/pages/edit-event/edit-event.page.ts

@@ -45,6 +45,7 @@ import { CanLeave } from '@guards/can-leave';
 import { CoreForms } from '@singletons/form';
 import { CoreReminders, CoreRemindersService, CoreRemindersUnits } from '@features/reminders/services/reminders';
 import { CoreRemindersSetReminderMenuComponent } from '@features/reminders/components/set-reminder-menu/set-reminder-menu';
+import moment from 'moment-timezone';
 
 /**
  * Page that displays a form to create/edit an event.
@@ -454,8 +455,8 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy, CanLeave {
     async submit(): Promise<void> {
         // Validate data.
         const formData = this.form.value;
-        const timeStartDate = CoreTimeUtils.convertToTimestamp(formData.timestart, true);
+        const timeStartDate = moment(formData.timestart).unix();
-        const timeUntilDate = CoreTimeUtils.convertToTimestamp(formData.timedurationuntil, true);
+        const timeUntilDate = moment(formData.timedurationuntil).unix();
         const timeDurationMinutes = parseInt(formData.timedurationminutes || '', 10);
         let error: string | undefined;
 

src/addons/mod/data/fields/date/component/addon-mod-data-field-date.html

@@ -1,7 +1,7 @@
 <span *ngIf="inputMode && form" [formGroup]="form">
     <span *ngIf="editMode" [core-mark-required]="field.required" class="core-mark-required"></span>
     <ion-datetime [formControlName]="'f_'+field.id" [placeholder]="'core.date' | translate" [max]="maxDate" [min]="minDate"
-        [disabled]="searchMode && !searchFields!['f_'+field.id+'_z']" [displayFormat]="format" display-timezone="utc">
+        [disabled]="searchMode && !searchFields!['f_'+field.id+'_z']" [displayFormat]="format">
     </ion-datetime>
     <core-input-errors *ngIf="error && editMode" [control]="form.controls['f_'+field.id]" [errorText]="error"></core-input-errors>
 

src/addons/userprofilefield/datetime/services/handlers/datetime.ts

@@ -18,9 +18,9 @@ import { AuthEmailSignupProfileField } from '@features/login/services/login-help
 import { CoreUserProfileField } from '@features/user/services/user';
 import { CoreUserProfileFieldHandler, CoreUserProfileFieldHandlerData } from '@features/user/services/user-profile-field-delegate';
 import { CoreFormFields } from '@singletons/form';
-import { CoreTimeUtils } from '@services/utils/time';
 import { makeSingleton } from '@singletons';
 import { AddonUserProfileFieldDatetimeComponent } from '../../component/datetime';
+import moment from 'moment-timezone';
 
 /**
  * Datetime user profile field handlers.
@@ -61,7 +61,7 @@ export class AddonUserProfileFieldDatetimeHandlerService implements CoreUserProf
             return {
                 type: 'datetime',
                 name: 'profile_field_' + field.shortname,
-                value: CoreTimeUtils.convertToTimestamp(<string> formValues[name]),
+                value: moment(<string> formValues[name]).unix(),
             };
         }
     }

src/core/services/utils/time.ts

@@ -261,23 +261,14 @@ export class CoreTimeUtilsProvider {
     /**
      * Convert a text into user timezone timestamp.
      *
-     * @todo The `applyOffset` argument is only used as a workaround, it should be removed once
-     * MOBILE-3784 is resolved.
-     *
      * @param date To convert to timestamp.
      * @param applyOffset Whether to apply offset to date or not.
      * @return Converted timestamp.
+     * @deprecated since 4.1. Use moment(date).unix() instead.
      */
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
     convertToTimestamp(date: string, applyOffset?: boolean): number {
-        const timestamp = moment(date).unix();
+        return moment(date).unix();
-
-        if (applyOffset !== undefined) {
-            return applyOffset ? timestamp - moment().utcOffset() * 60 : timestamp;
-        }
-
-        return typeof date == 'string' && date.slice(-1) == 'Z'
-            ? timestamp - moment().utcOffset() * 60
-            : timestamp;
     }
 
     /**