Added some qol improvements

BetterIServ.Mobile/src/app/api/storage.service.ts

@@ -1,8 +1,9 @@
 import { Injectable } from '@angular/core';
 import {HttpClient} from "@angular/common/http";
-import {firstValueFrom} from "rxjs";
+import {firstValueFrom, Observable} from "rxjs";
 import {environment} from "../../environments/environment";
 import {IServService} from "./iserv.service";
+import {Lesson} from "../entities/course";
 
 @Injectable({
   providedIn: 'root'
@@ -11,23 +12,56 @@ export class StorageService {
 
   constructor(private client: HttpClient) {}
 
-  public async getItem<T>(item: string, isJson: boolean = true): Promise<T> {
+  public async getItem<T>(item: string, isJson: boolean = true, defaultValue: T = undefined): Promise<T> {
     try {
       const data = await firstValueFrom(this.client.get<{value: string}>(environment.backend + `/storage?user=${IServService.userdata.username}&item=${item}`));
 
       if (isJson) return JSON.parse(data.value) as T;
-      return data.value as T;
+      else return data.value as T;
     }catch {
-      return undefined;
+      return defaultValue;
     }
   }
 
+  public getItemLocal<T>(item: string, isJson: boolean = true, defaultValue: T = undefined): Observable<T> {
+    return new Observable<T>((result) => {
+      const local = localStorage.getItem(item);
+
+      if (local != undefined) {
+        if (isJson) result.next(JSON.parse(local) as T);
+        else result.next(local as T);
+      }
+
+      setTimeout(async () => {
+        const response = await this.getItem<T>(item, isJson, defaultValue);
+        localStorage.setItem(item, isJson ? JSON.stringify(response) : response as string);
+        result.next(response);
+        result.complete();
+      }, 0);
+    })
+  }
+
   public async setItem(item: string, value: any) {
+    localStorage.setItem(item, value);
     await firstValueFrom(this.client.post(environment.backend + `/storage?user=${IServService.userdata.username}&item=${item}`, value));
   }
 
-  public async clear() {
-    await firstValueFrom(this.client.delete(environment.backend + `/storage?user=${IServService.userdata.username}`));
+  public isLessonThisWeek(lesson: Lesson): boolean {
+    const week = this.getWeek(new Date()) % 2;
+    const label = week == 0 ? "a" : "b";
+    return (lesson != undefined && (lesson.week == "all" || lesson.week == label));
+  }
+
+  private getWeek(orig: Date): number {
+    const date = new Date(orig.getTime());
+    date.setHours(0, 0, 0, 0);
+    // Thursday in current week decides the year.
+    date.setDate(date.getDate() + 3 - (date.getDay() + 6) % 7);
+    // January 4 is always in week 1.
+    const week1 = new Date(date.getFullYear(), 0, 4);
+    // Adjust to Thursday in week 1 and count number of weeks from date to week1.
+    return 1 + Math.round(((date.getTime() - week1.getTime()) / 86400000
+      - 3 + (week1.getDay() + 6) % 7) / 7);
   }
 
 }