finalized desktop version and first try implementing mobile

caesar-tauri-angular/src/app/services/storage.service.ts

@@ -0,0 +1,58 @@
+import { Injectable } from '@angular/core';
+
+@Injectable({
+  providedIn: 'root'
+})
+export class StorageService {
+
+	// ----------------- Session ------------------------
+  // Ruft einen Wert aus dem sessionStorage ab
+  getSessionEntry(key: string): any {
+    const item = sessionStorage.getItem(key);
+    return item ? JSON.parse(item) : null;
+  }
+
+	public setSessionEntry(key: string, data: unknown): void {
+		sessionStorage.setItem(key, JSON.stringify(data));
+	}
+
+	public deleteSessionEntry(key: string): void {
+		sessionStorage.removeItem(key);
+	}
+
+	public clearSession(): void {
+		sessionStorage.clear();
+	}
+
+	public isSessionEmpty(): boolean {
+		return sessionStorage.length === 0;
+	}
+
+	// ----------------- Local ------------------------
+	public setLocalEntry(key: string, data: unknown): void {
+		localStorage.setItem(key, JSON.stringify(data));
+	}
+
+	public getLocalEntry(key: string): any {
+    const item = localStorage.getItem(key);
+    return item ? JSON.parse(item) : null;
+  }
+
+	public deleteLocalEntry(key: string): void {
+		localStorage.removeItem(key);
+	}
+
+	public clearLocal(): void {
+		localStorage.clear();
+	}
+
+	public isLocalEmpty(): boolean {
+		return localStorage.length === 0;
+	}
+
+	// ----------------- General ------------------------
+	public clearAll(): void {
+		this.clearLocal();
+		this.clearSession();
+	}
+}