feat(backend): sessions routes

packages/backend/src/app.ts

@@ -4,6 +4,7 @@ import type { Db } from './db/client.js';
 import { ApiError } from './lib/errors.js';
 import { cardsRouter } from './routes/cards.js';
 import { lessonsRouter } from './routes/lessons.js';
+import { sessionsRouter } from './routes/sessions.js';
 
 export function createApp(db: Db): Express {
   const app = express();
@@ -12,6 +13,7 @@ export function createApp(db: Db): Express {
   app.get('/api/health', (_req, res) => res.json({ ok: true }));
   app.use('/api/lessons', lessonsRouter(db));
   app.use('/api', cardsRouter(db));
+  app.use('/api/sessions', sessionsRouter(db));
 
   app.use((err: unknown, _req: Request, res: Response, _next: NextFunction) => {
     if (err instanceof ZodError) {

packages/backend/src/routes/sessions.ts

@@ -0,0 +1,57 @@
+import { Router } from 'express';
+import { attemptCreateSchema, sessionStartSchema } from '@flashcard/shared';
+import type { Db } from '../db/client.js';
+import {
+  abandonSession, endSession, getActiveSession, getNextItem, getSessionState,
+  recordAttempt, startSession,
+} from '../services/sessions.js';
+import { ApiError } from '../lib/errors.js';
+
+export function sessionsRouter(db: Db): Router {
+  const r = Router();
+
+  r.post('/', async (req, res, next) => {
+    try {
+      const input = sessionStartSchema.parse(req.body);
+      res.status(201).json(await startSession(db, input));
+    } catch (e) { next(e); }
+  });
+
+  r.get('/active', async (_req, res, next) => {
+    try { res.json(await getActiveSession(db)); } catch (e) { next(e); }
+  });
+
+  r.get('/:id', async (req, res, next) => {
+    try {
+      const state = await getSessionState(db, Number(req.params.id));
+      if (!state) throw ApiError.notFound('Session');
+      res.json(state);
+    } catch (e) { next(e); }
+  });
+
+  r.get('/:id/next', async (req, res, next) => {
+    try {
+      const item = await getNextItem(db, Number(req.params.id));
+      if (!item) { res.json({ done: true }); return; }
+      res.json({ done: false, item });
+    } catch (e) { next(e); }
+  });
+
+  r.post('/:id/attempts', async (req, res, next) => {
+    try {
+      const input = attemptCreateSchema.parse(req.body);
+      await recordAttempt(db, Number(req.params.id), input);
+      res.status(204).end();
+    } catch (e) { next(e); }
+  });
+
+  r.post('/:id/end', async (req, res, next) => {
+    try { res.json(await endSession(db, Number(req.params.id))); } catch (e) { next(e); }
+  });
+
+  r.post('/:id/abandon', async (req, res, next) => {
+    try { res.json(await abandonSession(db, Number(req.params.id))); } catch (e) { next(e); }
+  });
+
+  return r;
+}