feat: add notes functionality to exam state and update UI for note-taking

backend/src/routes/results.ts

@@ -67,7 +67,7 @@ router.get('/:id', requireAuth, (req, res) => {
 // ─── Save Result ─────────────────────────────────────────
 router.post('/', requireAuth, (req, res) => {
   try {
-    const { title, scorePoints, totalPoints, correctCount, gradedCount, passingScore, elapsedMs, state, exam, examId } = req.body
+    const { title, scorePoints, totalPoints, correctCount, gradedCount, passingScore, elapsedMs, notes, state, exam, examId } = req.body
 
     if (
       !title || scorePoints == null || totalPoints == null ||
@@ -77,6 +77,17 @@ router.post('/', requireAuth, (req, res) => {
       return
     }
 
+    let noteSource = ''
+    if (typeof notes === 'string') {
+      noteSource = notes
+    } else if (typeof state.notes === 'string') {
+      noteSource = state.notes
+    }
+    const normalizedState = {
+      ...state,
+      notes: noteSource.slice(0, 1000),
+    }
+
     const db = getDb()
     const result = db.prepare(`
       INSERT INTO exam_results (user_id, exam_id, title, score_points, total_points, correct_count, graded_count, passing_score, elapsed_ms, state_json, exam_json)
@@ -91,7 +102,7 @@ router.post('/', requireAuth, (req, res) => {
       gradedCount,
       passingScore ?? 60,
       elapsedMs ?? 0,
-      JSON.stringify(state),
+      JSON.stringify(normalizedState),
       JSON.stringify(exam),
     )
 

frontend/src/App.tsx

@@ -14,6 +14,11 @@ import ResetPassword from './components/ResetPassword'
 
 const DEFAULT_TWEAKS: Tweaks = { theme: 'light', fontSize: 'medium', feedbackMode: 'auto' }
 
+const withNotes = (state: ExamState): ExamState => ({
+  ...state,
+  notes: state.notes ?? '',
+})
+
 function AppInner() {
   const { user, loading: authLoading, logout } = useAuth()
   const [screen, setScreen] = useState<AppScreen>('landing')
@@ -27,8 +32,8 @@ function AppInner() {
 
   // Check URL for verify/reset-password routes on mount
   useEffect(() => {
-    const path = window.location.pathname
+    const path = globalThis.location.pathname
-    const search = window.location.search
+    const search = globalThis.location.search
     if (path === '/verify' || search.includes('token=') && path === '/verify') {
       setScreen('verify')
     } else if (path === '/reset-password') {
@@ -56,7 +61,7 @@ function AppInner() {
             scorePoints: r.score_points,
             passingScore: r.passing_score,
             exam: { title: r.title, questions: [] } as unknown as Exam,
-            state: { currentIdx: 0, answers: {}, flags: {}, startedAt: 0, feedbackMode: 'end' as const } as ExamState,
+            state: { currentIdx: 0, answers: {}, flags: {}, notes: '', startedAt: 0, feedbackMode: 'end' as const } as ExamState,
             _remoteId: r.id,
           }))
           setHistory(apiHistory)
@@ -81,16 +86,25 @@ function AppInner() {
   const updateTweak = <K extends keyof Tweaks>(key: K, value: Tweaks[K]) =>
     setTweaks((t) => ({ ...t, [key]: value }))
 
+  const setExamStateStrict: React.Dispatch<React.SetStateAction<ExamState>> = (nextState) => {
+    setExamState((prev) => {
+      if (!prev) return prev
+      return typeof nextState === 'function'
+        ? (nextState as (prevState: ExamState) => ExamState)(prev)
+        : nextState
+    })
+  }
+
   const loadExam = (data: Exam) => {
     const fm = tweaks.feedbackMode === 'auto' ? (data.feedbackMode ?? 'end') : tweaks.feedbackMode
     setExam(data)
-    setExamState({ currentIdx: 0, answers: {}, flags: {}, revealed: {}, startedAt: Date.now(), feedbackMode: fm })
+    setExamState({ currentIdx: 0, answers: {}, flags: {}, notes: '', revealed: {}, startedAt: Date.now(), feedbackMode: fm })
     setScreen('exam')
   }
 
   const resume = () => {
     const saved = loadState()
-    if (saved?.exam && saved?.state) { setExam(saved.exam); setExamState(saved.state); setScreen('exam') }
+    if (saved?.exam && saved?.state) { setExam(saved.exam); setExamState(withNotes(saved.state)); setScreen('exam') }
   }
 
   const submit = useCallback(() => {
@@ -124,6 +138,7 @@ function AppInner() {
           gradedCount: entry.gradedCount,
           passingScore: entry.passingScore,
           elapsedMs: entry.elapsedMs,
+          notes: entry.state.notes,
           state: entry.state,
           exam: entry.exam,
         }),
@@ -155,15 +170,15 @@ function AppInner() {
       }>(`/api/results/${remoteId}`)
         .then((data) => {
           setExam(data.exam)
-          setExamState(data.state)
+          setExamState(withNotes(data.state))
           setScreen('review')
         })
         .catch(() => {
           // Fallback to local data
-          setExam(entry.exam); setExamState(entry.state); setScreen('review')
+          setExam(entry.exam); setExamState(withNotes(entry.state)); setScreen('review')
         })
     } else {
-      setExam(entry.exam); setExamState(entry.state); setScreen('review')
+      setExam(entry.exam); setExamState(withNotes(entry.state)); setScreen('review')
     }
   }
 
@@ -174,14 +189,8 @@ function AppInner() {
     }
   }
 
-  const handleVerifyDone = () => {
+  const handleAuthFlowDone = () => {
-    window.history.replaceState({}, '', '/')
+    globalThis.history.replaceState({}, '', '/')
-    setScreen('landing')
-    setAuthModalOpen(true)
-  }
-
-  const handleResetDone = () => {
-    window.history.replaceState({}, '', '/')
     setScreen('landing')
     setAuthModalOpen(true)
   }
@@ -195,7 +204,7 @@ function AppInner() {
             <span className="brand-name">BrainWave</span>
           </div>
         </header>
-        <EmailVerify onDone={handleVerifyDone} />
+        <EmailVerify onDone={handleAuthFlowDone} />
       </div>
     )
   }
@@ -209,7 +218,7 @@ function AppInner() {
             <span className="brand-name">BrainWave</span>
           </div>
         </header>
-        <ResetPassword onDone={handleResetDone} />
+        <ResetPassword onDone={handleAuthFlowDone} />
       </div>
     )
   }
@@ -274,7 +283,7 @@ function AppInner() {
         <Landing onLoadExam={loadExam} history={history} onResume={resume} onClearHistory={clearAllHistory} onReviewAttempt={reviewAttempt} />
       )}
       {screen === 'exam' && exam && examState && (
-        <ExamRunner exam={exam} state={examState} setState={setExamState as React.Dispatch<React.SetStateAction<ExamState>>} onSubmit={submit} onExit={exit} />
+        <ExamRunner exam={exam} state={examState} setState={setExamStateStrict} onSubmit={submit} onExit={exit} />
       )}
       {(screen === 'results' || screen === 'review') && exam && examState && (
         <Results exam={exam} state={examState} onRestart={restart} onExit={exit} reviewOnly={screen === 'review'} />

frontend/src/components/ExamRunner.tsx

@@ -14,10 +14,11 @@ interface Props {
   onExit: () => void
 }
 
-export default function ExamRunner({ exam, state, setState, onSubmit, onExit }: Props) {
+export default function ExamRunner({ exam, state, setState, onSubmit, onExit }: Readonly<Props>) {
   const { currentIdx, answers, flags, startedAt, feedbackMode } = state
   const q = exam.questions[currentIdx]
   const total = exam.questions.length
+  const notes = state.notes ?? ''
 
   const [revealed, setRevealed] = useState(() => !!state.revealed?.[q.id])
   useEffect(() => { setRevealed(!!state.revealed?.[q.id]) }, [currentIdx, q.id, state.revealed])
@@ -31,8 +32,14 @@ export default function ExamRunner({ exam, state, setState, onSubmit, onExit }:
   const toggleFlag = useCallback(() =>
     setState((s) => ({ ...s, flags: { ...s.flags, [q.id]: !s.flags[q.id] } })), [q.id])
 
+  const updateNotes = (value: string) =>
+    setState((s) => ({ ...s, notes: value.slice(0, 1000) }))
+
   const checkAnswer = () => {
-    setState((s) => ({ ...s, revealed: { ...(s.revealed ?? {}), [q.id]: true } }))
+    setState((s) => ({
+      ...s,
+      revealed: s.revealed ? { ...s.revealed, [q.id]: true } : { [q.id]: true },
+    }))
     setRevealed(true)
   }
 
@@ -58,13 +65,13 @@ export default function ExamRunner({ exam, state, setState, onSubmit, onExit }:
       if (e.key === 'ArrowLeft' || e.key === 'k') goTo(currentIdx - 1)
       if (e.key === 'f') toggleFlag()
       if (/^[1-9]$/.test(e.key) && q.type === 'multiple-choice' && q.choices) {
-        const ci = parseInt(e.key, 10) - 1
+        const ci = Number.parseInt(e.key, 10) - 1
         const choices = q.choices
         if (choices[ci]) setState((s) => ({ ...s, answers: { ...s.answers, [q.id]: choices[ci].id } }))
       }
     }
-    window.addEventListener('keydown', handler)
+    globalThis.addEventListener('keydown', handler)
-    return () => window.removeEventListener('keydown', handler)
+    return () => globalThis.removeEventListener('keydown', handler)
   }, [currentIdx, q, goTo, toggleFlag, setState])
 
   const graded = feedbackMode === 'immediate' && revealed
@@ -90,6 +97,12 @@ export default function ExamRunner({ exam, state, setState, onSubmit, onExit }:
   }).length
 
   const totalPossible = exam.questions.reduce((acc, qq) => acc + (qq.points ?? 1), 0)
+  let answerText = ''
+  if (!Array.isArray(q.answer) && typeof q.answer === 'string') {
+    answerText = q.choices?.find((c) => c.id === q.answer)?.text ?? q.answer
+  } else if (Array.isArray(q.answer)) {
+    answerText = q.answer.map((id) => q.choices?.find((c) => c.id === id)?.text ?? id).join(', ')
+  }
 
   return (
     <div className="exam-shell">
@@ -145,11 +158,7 @@ export default function ExamRunner({ exam, state, setState, onSubmit, onExit }:
               {!result.correct && q.answer && q.type !== 'match' && q.type !== 'order' && (
                 <p>
                   <strong>Answer:</strong>{' '}
-                  <Tex>
+                  <Tex>{answerText}</Tex>
-                    {Array.isArray(q.answer)
-                      ? (q.answer as string[]).map((id) => q.choices?.find((c) => c.id === id)?.text ?? id).join(', ')
-                      : (q.choices?.find((c) => c.id === q.answer)?.text ?? String(q.answer))}
-                  </Tex>
                 </p>
               )}
               {q.explanation && <p><Tex>{q.explanation}</Tex></p>}
@@ -201,6 +210,18 @@ export default function ExamRunner({ exam, state, setState, onSubmit, onExit }:
             {feedbackMode === 'immediate' ? 'Immediate feedback' : 'Grade at end'}
           </div>
         </div>
+        <div className="meta-block notes-block">
+          <div className="meta-label">Notes</div>
+          <textarea
+            className="textarea notes-pad"
+            value={notes}
+            onChange={(e) => updateNotes(e.target.value)}
+            placeholder="Add short notes while you work..."
+            maxLength={1000}
+            aria-label="Exam notes"
+          />
+          <div className="notes-count mono">{notes.length}/1000</div>
+        </div>
         {exam.author && (
           <div className="meta-block">
             <div className="meta-label">Author</div>

frontend/src/index.css

@@ -390,6 +390,7 @@ input, textarea, select { font-family: inherit; font-size: inherit; color: inher
   background: var(--paper);
   overflow-y: auto;
   position: sticky; top: 57px;
+  height: calc(100vh - 57px);
   max-height: calc(100vh - 57px);
 }
 .sidebar-title {
@@ -472,6 +473,7 @@ input, textarea, select { font-family: inherit; font-size: inherit; color: inher
   padding: 24px 20px;
   background: var(--paper);
   position: sticky; top: 57px;
+  height: calc(100vh - 57px);
   max-height: calc(100vh - 57px);
   overflow-y: auto;
 }
@@ -493,6 +495,21 @@ input, textarea, select { font-family: inherit; font-size: inherit; color: inher
 }
 .meta-value.mono { font-family: var(--font-mono); font-size: 18px; font-weight: 500; }
 
+.notes-block { margin-top: 2px; }
+.notes-pad {
+  height: clamp(100px, 20vh, 160px);
+  font-size: 13px;
+  line-height: 1.45;
+  resize: none;
+  overflow-y: auto;
+}
+.notes-count {
+  margin-top: 6px;
+  font-size: 11px;
+  color: var(--ink-4);
+  text-align: right;
+}
+
 .progress-bar {
   height: 3px;
   background: var(--line);

frontend/src/types.ts

@@ -84,6 +84,7 @@ export interface ExamState {
   currentIdx: number
   answers: Record<string, unknown>
   flags: Record<string, boolean>
+  notes: string
   revealed?: Record<string, boolean>
   startedAt: number
   completedAt?: number