WEB-693: Implement Date and Datetime Global Variables (#3123)

Signed-off-by: DeathGun44 <krishnamewara841@gmail.com>

src/app/pipes/datetime-format.pipe.ts

@@ -6,13 +6,38 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
 
-import { Pipe, PipeTransform } from '@angular/core';
+import { Pipe, PipeTransform, inject, OnDestroy } from '@angular/core';
+import { SettingsService } from 'app/settings/settings.service';
+import { TranslateService } from '@ngx-translate/core';
+import { Dates } from 'app/core/utils/dates';
+import { Subscription } from 'rxjs';
 import moment, { Moment } from 'moment';
 
-@Pipe({ name: 'datetimeFormat', standalone: true })
-export class DatetimeFormatPipe implements PipeTransform {
+@Pipe({ name: 'datetimeFormat', pure: false })
+export class DatetimeFormatPipe implements PipeTransform, OnDestroy {
+  private settingsService = inject(SettingsService);
+  private translateService = inject(TranslateService);
+  private dateUtils = inject(Dates);
+  private onLangChange: Subscription;
+
+  constructor() {
+    this.onLangChange = this.translateService.onLangChange.subscribe(() => {});
+  }
+
+  ngOnDestroy(): void {
+    if (this.onLangChange) {
+      this.onLangChange.unsubscribe();
+    }
+  }
+
   transform(value: unknown, datetimeFormat?: string): string {
+    const defaultDatetimeFormat = this.dateUtils.angularToMomentFormat(this.settingsService.datetimeFormat);
+
     if (value == null || value === '') return '';
+
+    const momentLocale = this.dateUtils.getMomentLocale(this.settingsService.language);
+    moment.locale(momentLocale);
+
     let dateVal: Moment;
     if (Array.isArray(value)) {
       const [
@@ -24,17 +49,31 @@ export class DatetimeFormatPipe implements PipeTransform {
         ss
       ] = value as number[];
       if (hh != null) {
-        dateVal = moment({ year: y, month: (m ?? 1) - 1, date: d, hour: hh, minute: mm ?? 0, second: ss ?? 0 });
+        dateVal = moment({
+          year: y,
+          month: (m ?? 1) - 1,
+          date: d,
+          hour: hh,
+          minute: mm ?? 0,
+          second: ss ?? 0
+        });
       } else {
         dateVal = moment({ year: y, month: (m ?? 1) - 1, date: d });
       }
     } else if (typeof value === 'number' && value < 1e12) {
-      // epoch seconds
       dateVal = moment.unix(value);
     } else {
       dateVal = moment(value as any);
     }
-    const fmt = datetimeFormat ?? 'YYYY-MM-DDTHH:mm:ssZ';
-    return dateVal.format(fmt);
+
+    if (!dateVal.isValid()) {
+      return '';
+    }
+
+    if (!datetimeFormat) {
+      return dateVal.format(defaultDatetimeFormat);
+    }
+
+    return dateVal.format(datetimeFormat);
   }
 }