# Code Review Fixes Summary

## Critical Issues Fixed ✅

### 1. **Listener Leak in sendInputAsync** (Lines 541-610)
**Issue**: Listeners registered for `done` and `error` events were never removed after completion, causing memory leak and performance degradation over time.

**Fix**: Implemented self-cleanup mechanism:
```java
// Listeners now remove themselves after triggering
doneConsumerRef[0] = doneData -> {
    off("done", doneConsumerRef[0]);
    off("error", errorConsumerRef[0]);
    future.complete(null);
};
```

**Impact**: Prevents memory leaks and ensures listeners don't accumulate over long sessions.

---

### 2. **Scheduler Resource Leak** (Line 233)
**Issue**: `ScheduledExecutorService` was never shut down in `disconnect()`, causing resource leak.

**Fix**: Added scheduler shutdown:
```java
public void disconnect() {
    // ... existing cleanup ...
    scheduler.shutdownNow();  // Release thread pool resources
}
```

**Impact**: Proper resource cleanup when client is disconnected.

---

### 3. **Listener Cleanup on Disconnect** (Line 232)
**Issue**: Event listeners persisted after `disconnect()`, causing memory leak if client reconnected.

**Fix**: Added `clearListeners()` method and call in `disconnect()`:
```java
public void disconnect() {
    // ... existing cleanup ...
    clearListeners();  // Remove all event listeners
    emit("disconnected", "Client initiated disconnect");
    scheduler.shutdownNow();
}

public void clearListeners() {
    listeners.clear();
}
```

**Impact**: Prevents listener accumulation across reconnection cycles.

---

### 4. **Heartbeat Timeout Handler Accumulation** (Lines 666-683)
**Issue**: Each ping scheduled a new timeout check without canceling previous ones, causing multiple timeout handlers to fire after network issues.

**Fix**: Track and cancel previous timeout before scheduling new one:
```java
private ScheduledFuture<?> pongTimeoutFuture;  // Added field

private void sendPing() {
    // ... send ping ...

    // Cancel previous timeout if pending
    if (pongTimeoutFuture != null) {
        pongTimeoutFuture.cancel(false);
    }

    // Schedule new timeout check
    pongTimeoutFuture = scheduler.schedule(() -> {
        // ... timeout logic ...
    }, PONG_TIMEOUT_MS, TimeUnit.MILLISECONDS);
}
```

**Impact**: Prevents CPU waste and incorrect missed pong counts.

---

## High-Priority Refactoring ✅

### 5. **Connection Validation Helper** (Lines 510-518)
**Issue**: Duplicated connection check in 4+ methods.

**Fix**: Extracted `requireConnected()` helper:
```java
private void requireConnected() {
    if (!connected || sessionId == null) {
        throw new IllegalStateException("Not connected to gateway");
    }
}

// Usage in sendInput, sendControl, sendPermissionResponse:
public void sendInput(String content, Map<String, Object> metadata) {
    requireConnected();  // Cleaner than inline check
    // ... rest of method
}
```

**Impact**: Reduces ~12 lines of duplicated code, centralized error handling.

---

### 6. **Envelope Send Helper** (Lines 520-535)
**Issue**: Repeated JSON serialization + send pattern in 7+ places.

**Fix**: Extracted `sendEnvelope()` helper:
```java
private void sendEnvelope(Envelope envelope) throws IOException {
    if (session == null || !session.isOpen()) {
        throw new IllegalStateException("WebSocket session not open");
    }
    String json = objectMapper.writeValueAsString(envelope);
    session.sendMessage(new TextMessage(json + "\n"));
}

// Simplified usage:
public void sendInput(String content, Map<String, Object> metadata) {
    requireConnected();
    try {
        InputData inputData = new InputData(content, metadata);
        Envelope envelope = createEnvelope(EventKind.Input.getValue(), inputData, "control");
        sendEnvelope(envelope);  // Much cleaner!
        log.debug("Sent input envelope");
    } catch (Exception e) {
        log.error("Failed to send input", e);
        throw new RuntimeException("Failed to send input", e);
    }
}
```

**Impact**: Reduces ~35 lines of duplicated code, centralized error handling.

---

## Medium-Priority Issues (Not Fixed Yet)

### 7. **JWT Builder Duplication** (JwtTokenGenerator.java)
**Status**: IDENTIFIED but not fixed in this iteration

**Issue**: Three near-identical token generation methods with repeated boilerplate.

**Recommendation**:
```java
// Extract common builder configuration
private JwtBuilder baseBuilder(String subject, List<String> scopes, long ttlSeconds) {
    Instant now = Instant.now();
    return Jwts.builder()
            .subject(subject)
            .issuer(issuer)
            .audience().add(audience).and()
            .issuedAt(Date.from(now))
            .expiration(Date.from(now.plusSeconds(ttlSeconds)))
            .claim("scopes", scopes)
            .signWith(keyPair.getPrivate(), Jwts.SIG.ES256);
}
```

**Impact**: Would reduce ~40 lines of code, prevent subtle bugs from divergent implementations.

---

### 8. **Stringly-Typed Event Routing** (HotPlexClient.java, lines 347-429)
**Status**: IDENTIFIED but not fixed in this iteration

**Issue**: Uses raw string literals instead of `EventKind` enum for event matching.

**Current**:
```java
switch (eventType) {
    case "error":          // Should use EventKind.Error.getValue()
    case "state":          // Should use EventKind.State.getValue()
    case "done":           // Should use EventKind.Done.getValue()
    // ...
}
```

**Recommendation**:
```java
switch (EventKind.fromValue(eventType)) {
    case Error:
        // ...
    case State:
        // ...
}
```

**Impact**: Type safety, prevents typos, better maintainability.

---

### 9. **Redundant State Flags**
**Status**: IDENTIFIED but not fixed

**Issue**: Multiple overlapping state flags (`connected`, `reconnecting`, `state`).

**Recommendation**: Derive `connected` from `state` to ensure consistency:
```java
public boolean isConnected() {
    return state == SessionState.Running || state == SessionState.Idle;
}
```

---

## Low-Priority Issues (Deferred)

### 10. **Unnecessary Section Comments**
**Status**: NOT ADDRESSED (cosmetic only)

Large section dividers add visual noise without explaining design rationale.

### 11. **Missing Action Validation in sendControl**
**Status**: NOT ADDRESSED (minor)

`sendControl` accepts any string for action, but only specific values are valid.

### 12. **Unused Token Variable in QuickStart**
**Status**: NOT ADDRESSED (minor)

Token generated but never used directly in example.

---

## Test Results

✅ **Compilation**: SUCCESS
```bash
[INFO] BUILD SUCCESS
[INFO] Total time:  1.008 s
[INFO] Compiling 24 source files
```

---

## Summary

### Fixed in This Iteration
- **4 Critical** resource leak and memory leak issues
- **2 High-priority** code duplication issues
- **~50 lines** of code reduced through helper methods
- **3 new helper methods**: `requireConnected()`, `sendEnvelope()`, `clearListeners()`

### Deferred to Future Iteration
- **2 Medium-priority** refactoring opportunities (JWT builder, event routing)
- **3 Low-priority** cosmetic/minor issues

### Impact
- ✅ Memory leak prevention
- ✅ Resource cleanup
- ✅ Code maintainability improved
- ✅ Reduced code duplication
- ✅ No breaking changes to public API

---

## Files Modified

1. **HotPlexClient.java**
   - Added `requireConnected()` helper
   - Added `sendEnvelope()` helper
   - Added `clearListeners()` method
   - Fixed listener leak in `sendInputAsync()`
   - Fixed heartbeat timeout accumulation
   - Added scheduler shutdown in `disconnect()`
   - Updated `sendInput()`, `sendControl()`, `sendPermissionResponse()` to use helpers

2. **JwtTokenGenerator.java**
   - Reviewed for duplication (not modified in this iteration)

3. **QuickStart.java**
   - Reviewed for issues (no changes required)

---

## Next Steps (Optional)

1. **JWT Refactoring**: Extract `baseBuilder()` method in `JwtTokenGenerator.java`
2. **Event Routing**: Use `EventKind` enum consistently in `routeEvent()`
3. **State Consolidation**: Derive `connected` from `state` enum
4. **Add Unit Tests**: Test listener cleanup, heartbeat timeout logic
5. **Performance Testing**: Verify no degradation under load

---

Generated by `/simplify` code review - 2026-04-03
