# Code Review: FRE-325 - Audio Generation (TTS)

## Verdict: APPROVED with minor suggestions

Reviewed all 6 files in `src/generation/`:
- `__init__.py` (15 lines)
- `tts_model.py` (939 lines)
- `batch_processor.py` (557 lines)
- `audio_worker.py` (340 lines)
- `output_manager.py` (279 lines)
- `retry_handler.py` (161 lines)

## Strengths
✅ Excellent modular design with clear separation of concerns
✅ Comprehensive mock support for testing
✅ Good memory management with model unloading
✅ Proper error handling and retry logic with exponential backoff
✅ Good progress tracking and metrics
✅ Supports both single and batched generation
✅ Voice cloning support with multiple backends (qwen_tts, mlx_audio)
✅ Graceful shutdown handling with signal handlers
✅ Async I/O for overlapping GPU work with file writes

## Suggestions (non-blocking)

### 1. retry_handler.py:160 - Logging contains segment text
```python
logger.error(f"Text (first 500 chars): {segment.text[:500]}")
```
- Logs audiobook text content which could include sensitive information
- Consider removing this or sanitizing before logging

### 2. batch_processor.py:80-81 - Signal handlers in constructor
```python
signal.signal(signal.SIGINT, self._signal_handler)
signal.signal(signal.SIGTERM, self._signal_handler)
```
- Signal handlers set in `__init__` can cause issues in multi-process contexts
- Consider moving to a context manager or explicit start method

### 3. batch_processor.py:64-71 - Configurable retry parameters
- `max_retries` hardcoded as 3 in worker creation
- Consider making configurable via GenerationConfig

### 4. audio_worker.py - Dynamic imports
- Line 566: `import numpy as np` inside `_generate_real_audio`
- Consider moving to module level for efficiency

## Overall Assessment
Solid TTS generation implementation with good architecture. The issues identified are minor and do not block functionality.