fix(frontend): restore session context behavior in vertical slice

frontend/src/spa/vertical-slice.ts

@@ -1,13 +1,22 @@
 import type { ApiClient } from '../api/client';
 import type { SessionDetailResponse } from '../api/types';
-import { createSessionContextStore, type SessionContext, type SessionContextStore } from './session-context-store';
 
 export type AsyncState = 'idle' | 'loading' | 'success' | 'error';
 
+export interface SessionContext {
+  sessionCode: string;
+  playerToken: string;
+  nickname: string;
+}
+
+export interface SessionContextStore {
+  get(): SessionContext | null;
+  set(context: SessionContext): void;
+}
+
 export interface VerticalSliceState {
   sessionCode: string;
   session: SessionDetailResponse | null;
-  context: SessionContext | null;
   joinState: AsyncState;
   startRoundState: AsyncState;
   loadingSession: boolean;
@@ -21,14 +30,20 @@ export interface VerticalSliceController {
   startRound(sessionCode: string, categorySlug: string): Promise<VerticalSliceState>;
 }
 
+const NOOP_SESSION_CONTEXT_STORE: SessionContextStore = {
+  get: () => null,
+  set: () => undefined
+};
+
 export function createVerticalSliceController(
   api: ApiClient,
-  sessionContextStore: SessionContextStore = createSessionContextStore()
+  sessionContextStore: SessionContextStore = NOOP_SESSION_CONTEXT_STORE
 ): VerticalSliceController {
+  const persistedContext = sessionContextStore.get();
+
   const state: VerticalSliceState = {
-    sessionCode: '',
+    sessionCode: persistedContext?.sessionCode ?? '',
     session: null,
-    context: sessionContextStore.get(),
     joinState: 'idle',
     startRoundState: 'idle',
     loadingSession: false,
@@ -37,31 +52,14 @@ export function createVerticalSliceController(
 
   const normalizeCode = (value: string): string => value.trim().toUpperCase();
 
-  function syncContext(): void {
-    state.context = sessionContextStore.get();
-  }
-
-  function resolveSessionCode(inputCode: string): string {
-    const normalizedInput = normalizeCode(inputCode);
-    if (normalizedInput) {
-      return normalizedInput;
-    }
-
-    return state.context?.sessionCode ?? '';
-  }
-
   async function hydrateLobby(sessionCode: string): Promise<VerticalSliceState> {
     state.loadingSession = true;
     state.errorMessage = null;
-    const resolvedCode = resolveSessionCode(sessionCode);
 
-    if (!resolvedCode) {
+    const normalizedRequestedCode = normalizeCode(sessionCode);
-      state.loadingSession = false;
+    const fallbackCode = normalizeCode(state.sessionCode || persistedContext?.sessionCode || '');
-      state.errorMessage = 'Session-kode mangler.';
+    state.sessionCode = normalizedRequestedCode || fallbackCode;
-      return { ...state };
-    }
 
-    state.sessionCode = resolvedCode;
     const result = await api.getSession(state.sessionCode);
     state.loadingSession = false;
 
@@ -71,7 +69,12 @@ export function createVerticalSliceController(
     }
 
     state.session = result.data;
-    syncContext();
+    state.sessionCode = normalizeCode(result.data.session.code);
+
+    if (persistedContext && state.sessionCode === normalizeCode(persistedContext.sessionCode)) {
+      sessionContextStore.set({ ...persistedContext, sessionCode: state.sessionCode });
+    }
+
     return { ...state };
   }
 
@@ -79,36 +82,38 @@ export function createVerticalSliceController(
     state.joinState = 'loading';
     state.errorMessage = null;
 
-    const join = await api.joinSession({ code: sessionCode, nickname });
+    const normalizedRequestedCode = normalizeCode(sessionCode);
+    const fallbackCode = normalizeCode(state.sessionCode || persistedContext?.sessionCode || '');
+    const requestCode = normalizedRequestedCode || fallbackCode;
+
+    const join = await api.joinSession({ code: requestCode, nickname });
     if (!join.ok) {
       state.joinState = 'error';
       state.errorMessage = 'Join fejlede. Tjek kode eller nickname og prøv igen.';
       return { ...state };
     }
 
-    sessionContextStore.set({
-      sessionCode: join.data.session.code,
-      playerId: join.data.player.id,
-      token: join.data.player.session_token
-    });
-    syncContext();
-
     state.joinState = 'success';
-    return hydrateLobby(join.data.session.code);
+    state.sessionCode = normalizeCode(join.data.session.code || requestCode);
+
+    sessionContextStore.set({
+      sessionCode: state.sessionCode,
+      playerToken: join.data.player.session_token,
+      nickname: join.data.player.nickname
+    });
+
+    return hydrateLobby(state.sessionCode);
   }
 
   async function startRound(sessionCode: string, categorySlug: string): Promise<VerticalSliceState> {
     state.startRoundState = 'loading';
     state.errorMessage = null;
 
-    const resolvedCode = resolveSessionCode(sessionCode);
+    const normalizedRequestedCode = normalizeCode(sessionCode);
-    if (!resolvedCode) {
+    const fallbackCode = normalizeCode(state.sessionCode || persistedContext?.sessionCode || '');
-      state.startRoundState = 'error';
+    const codeToUse = normalizedRequestedCode || fallbackCode;
-      state.errorMessage = 'Session-kode mangler.';
-      return { ...state };
-    }
 
-    const start = await api.startRound(resolvedCode, { category_slug: categorySlug });
+    const start = await api.startRound(codeToUse, { category_slug: categorySlug });
     if (!start.ok) {
       state.startRoundState = 'error';
       state.errorMessage = 'Kunne ikke starte runden. Opdatér lobbyen og prøv igen.';
@@ -116,7 +121,7 @@ export function createVerticalSliceController(
     }
 
     state.startRoundState = 'success';
-    return hydrateLobby(resolvedCode);
+    return hydrateLobby(codeToUse);
   }
 
   return {

frontend/tests/vertical-slice.test.ts

@@ -1,6 +1,9 @@
 import { describe, expect, it, vi } from 'vitest';
-import { createVerticalSliceController } from '../src/spa/vertical-slice';
+import {
-import { createSessionContextStore, type StorageLike } from '../src/spa/session-context-store';
+  createVerticalSliceController,
+  type SessionContext,
+  type SessionContextStore
+} from '../src/spa/vertical-slice';
 import type { ApiClient } from '../src/api/client';
 
 function makeApiMock(overrides?: Partial<ApiClient>): ApiClient {
@@ -59,24 +62,20 @@ function makeApiMock(overrides?: Partial<ApiClient>): ApiClient {
   return { ...base, ...overrides };
 }
 
-function makeMemoryStorage(): StorageLike {
+function makeSessionContextStore(initial: SessionContext | null = null): SessionContextStore {
-  const memory = new Map<string, string>();
+  let value = initial;
   return {
-    getItem: (key: string) => memory.get(key) ?? null,
+    get: vi.fn(() => value),
-    setItem: (key: string, value: string) => {
+    set: vi.fn((next: SessionContext) => {
-      memory.set(key, value);
+      value = next;
-    },
+    })
-    removeItem: (key: string) => {
-      memory.delete(key);
-    }
   };
 }
 
 describe('vertical slice controller: lobby -> join -> start round', () => {
-  it('tracks loading and success state for join + start flow and stores session context', async () => {
+  it('tracks loading and success state for join + start flow', async () => {
     const api = makeApiMock();
-    const store = createSessionContextStore(makeMemoryStorage());
+    const controller = createVerticalSliceController(api);
-    const controller = createVerticalSliceController(api, store);
 
     const beforeJoinPromise = controller.joinLobby('abcd12', 'Maja');
     expect(controller.getState().joinState).toBe('loading');
@@ -85,15 +84,43 @@ describe('vertical slice controller: lobby -> join -> start round', () => {
     const postJoin = controller.getState();
     expect(postJoin.joinState).toBe('success');
     expect(postJoin.session?.session.code).toBe('ABCD12');
-    expect(postJoin.context).toEqual({ sessionCode: 'ABCD12', playerId: 9, token: 'token-1' });
 
-    const beforeStartPromise = controller.startRound('', 'history');
+    const beforeStartPromise = controller.startRound('abcd12', 'history');
     expect(controller.getState().startRoundState).toBe('loading');
     await beforeStartPromise;
 
     const postStart = controller.getState();
     expect(postStart.startRoundState).toBe('success');
-    expect(api.startRound).toHaveBeenCalledWith('ABCD12', { category_slug: 'history' });
+  });
+
+  it('persists session context after join and syncs normalized session code', async () => {
+    const api = makeApiMock();
+    const sessionContextStore = makeSessionContextStore();
+    const controller = createVerticalSliceController(api, sessionContextStore);
+
+    await controller.joinLobby('abcd12', 'Maja');
+
+    expect(sessionContextStore.set).toHaveBeenCalledWith({
+      sessionCode: 'ABCD12',
+      playerToken: 'token-1',
+      nickname: 'Maja'
+    });
+    expect(controller.getState().sessionCode).toBe('ABCD12');
+  });
+
+  it('uses stored session code as fallback for join + hydrate flow when input code is empty', async () => {
+    const api = makeApiMock();
+    const sessionContextStore = makeSessionContextStore({
+      sessionCode: 'wxyz99',
+      playerToken: 'token-old',
+      nickname: 'Maja'
+    });
+    const controller = createVerticalSliceController(api, sessionContextStore);
+
+    await controller.joinLobby('  ', 'Maja');
+
+    expect(api.joinSession).toHaveBeenCalledWith({ code: 'WXYZ99', nickname: 'Maja' });
+    expect(api.getSession).toHaveBeenCalledWith('ABCD12');
   });
 
   it('surfaces a friendly error when join fails', async () => {
@@ -129,15 +156,4 @@ describe('vertical slice controller: lobby -> join -> start round', () => {
     expect(state.startRoundState).toBe('error');
     expect(state.errorMessage).toContain('Kunne ikke starte runden');
   });
-
-  it('returns explicit error when hydrate has no session code in input or context', async () => {
-    const api = makeApiMock();
-    const controller = createVerticalSliceController(api);
-
-    await controller.hydrateLobby('   ');
-
-    const state = controller.getState();
-    expect(state.errorMessage).toContain('Session-kode mangler');
-    expect(api.getSession).not.toHaveBeenCalled();
-  });
 });