tests/convert_cache_to_mp3.py

"""
Convert cached WAV files to MP3 for smaller size (GitHub 10MB limit)
Requires: pydub and ffmpeg
"""

import os
import json
from pathlib import Path

try:
    from pydub import AudioSegment
except ImportError:
    print("Installing pydub...")
    os.system("pip install pydub")
    from pydub import AudioSegment

def convert_wav_to_mp3(wav_path: str, mp3_path: str, bitrate: str = "128k"):
    """Convert WAV to MP3."""
    print(f"Converting {wav_path} -> {mp3_path}")
    audio = AudioSegment.from_wav(wav_path)
    audio.export(mp3_path, format="mp3", bitrate=bitrate)
    
    wav_size = os.path.getsize(wav_path) / (1024 * 1024)
    mp3_size = os.path.getsize(mp3_path) / (1024 * 1024)
    print(f"  WAV: {wav_size:.2f}MB -> MP3: {mp3_size:.2f}MB (saved {wav_size - mp3_size:.2f}MB)")

def update_cache_metadata(cache_dir: Path):
    """Update metadata.json to point to MP3 files."""
    metadata_file = cache_dir / "metadata.json"
    
    if not metadata_file.exists():
        print("No metadata.json found")
        return
    
    with open(metadata_file, 'r') as f:
        metadata = json.load(f)
    
    for key, entry in metadata.items():
        audio_file = entry.get('audio_file', '')
        if audio_file.endswith('.wav'):
            # Update to MP3
            mp3_file = audio_file.replace('.wav', '.mp3')
            entry['audio_file'] = mp3_file
            print(f"Updated metadata: {audio_file} -> {mp3_file}")
    
    with open(metadata_file, 'w') as f:
        json.dump(metadata, f, indent=2)
    
    print(f"\n✅ Updated {metadata_file}")

def main():
    cache_dir = Path("./cache")
    audio_dir = Path("./assets/audio")
    
    print("🎵 Converting cached WAV files to MP3\n")
    print("This reduces file size by ~90% to fit GitHub's 10MB limit\n")
    
    # Load metadata to find all cached audio files
    metadata_file = cache_dir / "metadata.json"
    if not metadata_file.exists():
        print("❌ No cache metadata found. Run generate_cache.py first.")
        return
    
    with open(metadata_file, 'r') as f:
        metadata = json.load(f)
    
    converted = 0
    for key, entry in metadata.items():
        audio_file = entry.get('audio_file', '')
        
        if not audio_file or not audio_file.endswith('.wav'):
            continue
        
        wav_path = Path(audio_file)
        if not wav_path.exists():
            print(f"⚠️  Not found: {wav_path}")
            continue
        
        # Convert to MP3
        mp3_path = wav_path.with_suffix('.mp3')
        
        if mp3_path.exists():
            print(f"✓ Already exists: {mp3_path}")
        else:
            try:
                convert_wav_to_mp3(str(wav_path), str(mp3_path), bitrate="128k")
                converted += 1
            except Exception as e:
                print(f"❌ Error converting {wav_path}: {e}")
    
    print(f"\n📊 Converted {converted} files")
    
    # Update metadata
    print("\n🔄 Updating cache metadata...")
    update_cache_metadata(cache_dir)
    
    # Clean up WAV files
    print("\n🗑️  Removing original WAV files...")
    for key, entry in metadata.items():
        audio_file = entry.get('audio_file', '')
        if audio_file:
            wav_path = Path(audio_file.replace('.mp3', '.wav'))
            if wav_path.exists() and wav_path.suffix == '.wav':
                size_mb = os.path.getsize(wav_path) / (1024 * 1024)
                os.remove(wav_path)
                print(f"  Removed {wav_path.name} ({size_mb:.2f}MB)")
    
    print("\n✅ Conversion complete!")
    print("\nNow you can commit:")
    print("  git add cache/ assets/audio/podcast_*.mp3")
    print("  git commit -m 'Add pre-generated MP3 podcast cache'")
    print("  git push")

if __name__ == "__main__":
    main()