# Daily Digest Podcast - PRD & Roadmap

## Current State (What We Have)

### ✅ Built & Working
- TTS generation (3 providers: OpenAI, Piper, macOS say)
- Audio storage in Supabase (`podcast-audio` bucket)
- RSS feed endpoint (`/api/podcast/rss`)
- Database schema (`audio_url`, `audio_duration`)
- Daily digest workflow at 7am CST

### ⚠️ Not Working / Disabled
- TTS generation is OFF (`ENABLE_TTS=false`)
- No music layering yet

---

## TODO: Music Layering Feature

### What We Need

1. **Intro/Outro Music Files**
   - Store MP3 files somewhere (Supabase Storage or local)
   - Need: 5-10 sec intro, 5-10 sec outro
   
2. **Audio Mixing with ffmpeg**
   - Layer: Intro → TTS Speech → Outro
   - Optional: Background music under speech (lower volume)

3. **Environment Config**
   - `INTRO_MUSIC_URL` - Path to intro file
   - `OUTRO_MUSIC_URL` - Path to outro file
   - `BACKGROUND_MUSIC_URL` - Optional background track
   - `MUSIC_VOLUME` - Background volume (0.1-0.3)

---

## Implementation Plan

### Phase 1: Basic TTS (Quick Win)
- [ ] Enable TTS in `.env.production`
- [ ] Test with OpenAI provider
- [ ] Verify audio appears on blog

### Phase 2: Music Files
- [ ] Source or create intro/outro music
- [ ] Upload to Supabase Storage bucket
- [ ] Add URLs to environment config

### Phase 3: Audio Mixing
- [ ] Add ffmpeg dependency
- [ ] Create mixing function in `tts.ts`
- [ ] Mix: Intro + TTS + Outro
- [ ] Optional: Background music layer

### Phase 4: Production
- [ ] Deploy with music mixing enabled
- [ ] Test full pipeline
- [ ] Verify RSS includes mixed audio

---

## Files Reference

| File | Purpose |
|------|---------|
| `src/lib/tts.ts` | TTS generation (add mixing here) |
| `src/lib/storage.ts` | Audio file upload/download |
| `src/app/api/tts/routeTS API endpoint |
| `src/app/api/digest/r.ts` | Toute.ts` | Digest creation + TTS trigger |
| `.env.production` | TTS config (ENABLE_TTS, TTS_PROVIDER, etc.) |

---

## Configuration Variables Needed

```bash
# Current (in .env.production)
ENABLE_TTS=true
TTS_PROVIDER=openai
TTS_VOICE=alloy
OPENAI_API_KEY=sk-...

# New (for music layering)
INTRO_MUSIC_URL=https://.../intro.mp3
OUTRO_MUSIC_URL=https://.../outro.mp3
BACKGROUND_MUSIC_URL=https://.../bg.mp3  # optional
MUSIC_VOLUME=0.2
```

---

## Blockers

~~1. **No intro/outro music files** - Need to source or create~~
~~2. **ffmpeg not installed on Vercel** - May need local-only generation or custom build~~

### Phase 1: Basic TTS - COMPLETE ✅
- [x] Enable TTS in `.env.production`
- [x] Test with OpenAI provider
- [x] Verify audio appears on blog

---

## Questions to Answer

1. Do you have intro/outro music already, or should we source it?
2. Prefer OpenAI TTS or Piper (local/free)?
3. Want background music under speech, or just intro/outro?