const KataPlayer = ( kata, onSubmit ) => ""); const [result, setResult] = useState(null); const runTests = () => // Run against kata.testCases const passed = kata.testCases.every(test => eval(userCode)(test.input) === test.expected ); setResult(passed ? "✅ Perfect form" : "❌ Try again"); if (passed) onSubmit(kata.id); ;

const MasteryTracker = ( userId, kataId ) => const [history, setHistory] = useState([]); // Log each attempt with timestamp and score const logAttempt = (score) => const newAttempt = date: new Date(), score ; setHistory([...history, newAttempt]); // Update user's mastery level based on 3+ successful attempts ;

return ( <div> <h4>Mastery path</h4> <div className="progress-bar" style= width: $masteryLevel% /> <p>history.length / 10 repetitions to black belt</p> </div> ); ; | Feature | Description | |--------|-------------| | Kata of the Day | Random recommended kata based on user level. | | Timed mode | Complete within X minutes to earn "speed belt". | | Compare replay | For movement katas: overlay user webcam vs sensei. | | Community variants | Users can fork a kata and change constraints. | | Streak counter | Daily kata completion streak. | 🗄️ Data Model (Simplified) interface Kata "black"; category: "arrays" interface UserKataProgress userId: string; kataId: string; attempts: number; lastCompleted: Date; bestTimeMs?: number; masteryLevel: number; // 0-100