fix: Fix multiple bugs with new authentication flow

toju-app/src/app/infrastructure/persistence/database.service.spec.ts

@@ -1,3 +1,4 @@
+import '@angular/compiler';
 import { Injector, runInInjectionContext } from '@angular/core';
 import {
   beforeEach,
@@ -13,6 +14,21 @@ import { CapacitorDatabaseService } from './capacitor-database.service';
 import { DatabaseService } from './database.service';
 import { ElectronDatabaseService } from './electron-database.service';
 
+function installLocalStorageMock(): void {
+  const store = new Map<string, string>();
+
+  vi.stubGlobal('localStorage', {
+    getItem: (key: string) => store.get(key) ?? null,
+    setItem: (key: string, value: string) => store.set(key, String(value)),
+    removeItem: (key: string) => store.delete(key),
+    clear: () => store.clear(),
+    key: (index: number) => Array.from(store.keys())[index] ?? null,
+    get length() {
+      return store.size;
+    }
+  });
+}
+
 describe('DatabaseService', () => {
   let browserDatabase: {
     getBansForRoom: ReturnType<typeof vi.fn>;
@@ -28,6 +44,9 @@ describe('DatabaseService', () => {
   };
 
   beforeEach(() => {
+    installLocalStorageMock();
+    localStorage.clear();
+
     browserDatabase = {
       getBansForRoom: vi.fn(() => Promise.resolve([])),
       initialize: vi.fn(() => Promise.resolve())
@@ -69,6 +88,56 @@ describe('DatabaseService', () => {
     expect(service.isReady()).toBe(true);
   });
 
+  it('rechecks backend initialization when the user scope changes during an in-flight initialize call', async () => {
+    let finishInitialInitialize!: () => void;
+
+    browserDatabase.initialize = vi.fn()
+      .mockImplementationOnce(() => new Promise<void>((resolve) => {
+        finishInitialInitialize = resolve;
+      }))
+      .mockResolvedValue(undefined);
+
+    localStorage.setItem('metoyou_currentUserId', 'user-a');
+
+    const service = createService({ isBrowser: true, isElectron: false, isCapacitor: false });
+    const initialInitialize = service.initialize();
+
+    localStorage.setItem('metoyou_currentUserId', 'user-b');
+    const initializeAfterScopeChange = service.initialize();
+
+    expect(browserDatabase.initialize).toHaveBeenCalledTimes(1);
+
+    finishInitialInitialize();
+    await Promise.all([initialInitialize, initializeAfterScopeChange]);
+
+    expect(browserDatabase.initialize).toHaveBeenCalledTimes(2);
+    expect(service.isReady()).toBe(true);
+  });
+
+  it('does not reinitialize the browser backend for repeated reads in the same user scope', async () => {
+    const service = createService({ isBrowser: true, isElectron: false, isCapacitor: false });
+
+    await service.getBansForRoom('room-1');
+    await service.getBansForRoom('room-2');
+
+    expect(browserDatabase.initialize).toHaveBeenCalledTimes(1);
+    expect(browserDatabase.getBansForRoom).toHaveBeenCalledWith('room-1');
+    expect(browserDatabase.getBansForRoom).toHaveBeenCalledWith('room-2');
+  });
+
+  it('reinitializes the browser backend when the stored user scope changes', async () => {
+    localStorage.setItem('metoyou_currentUserId', 'user-a');
+
+    const service = createService({ isBrowser: true, isElectron: false, isCapacitor: false });
+
+    await service.getBansForRoom('room-1');
+    localStorage.setItem('metoyou_currentUserId', 'user-b');
+    await service.getBansForRoom('room-2');
+
+    expect(browserDatabase.initialize).toHaveBeenCalledTimes(2);
+    expect(browserDatabase.getBansForRoom).toHaveBeenCalledWith('room-2');
+  });
+
   it('routes Capacitor shells to native SQLite instead of IndexedDB', async () => {
     const service = createService({ isBrowser: false, isElectron: false, isCapacitor: true });
 

toju-app/src/app/infrastructure/persistence/database.service.ts

@@ -14,6 +14,7 @@ import {
 } from '../../shared-kernel';
 import type { ChatAttachmentMeta, CustomEmoji } from '../../shared-kernel';
 import { PlatformService } from '../../core/platform';
+import { getStoredCurrentUserId } from '../../core/storage/current-user-storage';
 import { BrowserDatabaseService } from './browser-database.service';
 import { CapacitorDatabaseService } from './capacitor-database.service';
 import { resolveDatabaseBackend } from './database-backend.rules';
@@ -42,6 +43,7 @@ export class DatabaseService {
   private readonly capacitorDb = inject(CapacitorDatabaseService);
   private readonly electronDb = inject(ElectronDatabaseService);
   private initializationPromise: Promise<void> | null = null;
+  private validatedUserScope: string | null | undefined;
 
   /** Reactive flag: `true` once {@link initialize} has completed. */
   isReady = signal(false);
@@ -66,8 +68,15 @@ export class DatabaseService {
 
   /** Initialise the platform-specific database. */
   async initialize(): Promise<void> {
+    const userScope = getStoredCurrentUserId();
+
     if (this.initializationPromise) {
       await this.initializationPromise;
+
+      if (this.isReady() && this.validatedUserScope === userScope) {
+        return;
+      }
+    } else if (this.isReady() && this.validatedUserScope === userScope) {
       return;
     }
 
@@ -75,6 +84,7 @@ export class DatabaseService {
 
     this.initializationPromise = backend.initialize()
       .then(() => {
+        this.validatedUserScope = userScope;
         this.isReady.set(true);
       })
       .finally(() => {
@@ -85,8 +95,11 @@ export class DatabaseService {
   }
 
   private async ensureReady(): Promise<void> {
-    if (this.isReady())
+    const userScope = getStoredCurrentUserId();
+
+    if (this.isReady() && this.validatedUserScope === userScope) {
       return;
+    }
 
     await this.initialize();
   }