timezone service added

npm/ng-packs/packages/core/src/lib/services/index.ts

@@ -23,3 +23,4 @@ export * from './window.service';
 export * from './internet-connection-service';
 export * from './local-storage-listener.service';
 export * from './title-strategy.service';
+export * from './timezone.service';

npm/ng-packs/packages/core/src/lib/services/timezone.service.ts

@@ -0,0 +1,34 @@
+import { Injectable } from '@angular/core';
+
+@Injectable({
+  providedIn: 'root',
+})
+export class TimezoneService {
+  private readonly cookieKey = '__timezone';
+
+  getBrowserTimezone(): string {
+    return Intl.DateTimeFormat().resolvedOptions().timeZone;
+  }
+
+  getTimezone(): string {
+    const fromCookie = this.getCookie(this.cookieKey);
+    return fromCookie || this.getBrowserTimezone();
+  }
+
+  setTimezone(timezone: string): void {
+    document.cookie = `${this.cookieKey}=${timezone}; path=/`;
+  }
+
+  convertUtcToLocal(date: string | Date): Date {
+    return new Date(date + 'Z');
+  }
+
+  convertLocalToUtc(date: Date): string {
+    return date.toISOString();
+  }
+
+  private getCookie(name: string): string | null {
+    const match = document.cookie.match(new RegExp('(^| )' + name + '=([^;]+)'));
+    return match ? decodeURIComponent(match[2]) : null;
+  }
+}