# Julia AI Voice Integration

## Architecture Overview

```
┌─────────────────────────────────────────────────────────────────┐
│                    WellNuo Lite App (iOS)                       │
│  ┌─────────────────────────────────────────────────────────┐   │
│  │  Voice Call Screen (app/voice-call.tsx)                  │   │
│  │  - useLiveKitRoom hook                                   │   │
│  │  - Audio session management                              │   │
│  │  - Microphone permission handling                        │   │
│  └───────────────────────┬─────────────────────────────────┘   │
│                          │ WebSocket + WebRTC                   │
└──────────────────────────┼──────────────────────────────────────┘
                           │
                           ▼
┌─────────────────────────────────────────────────────────────────┐
│                   LiveKit Cloud                                  │
│  ┌─────────────────┐  ┌─────────────────┐  ┌─────────────────┐  │
│  │  SFU Server     │  │  Room Mgmt      │  │  Agent Hosting  │  │
│  │  (WebRTC)       │  │  (Token Auth)   │  │  (Python)       │  │
│  └────────┬────────┘  └─────────────────┘  └────────┬────────┘  │
│           │                                          │          │
│           └──────────────────────────────────────────┘          │
│                          │ Audio Streams                        │
└──────────────────────────┼──────────────────────────────────────┘
                           │
                           ▼
┌─────────────────────────────────────────────────────────────────┐
│                  Julia AI Agent (Python)                         │
│  ┌─────────────┐  ┌─────────────┐  ┌─────────────────────────┐  │
│  │ Deepgram    │  │ Deepgram    │  │ WellNuo voice_ask API   │  │
│  │ STT         │  │ TTS         │  │ (Custom LLM backend)    │  │
│  │ (Nova-2)    │  │ (Aura)      │  │                         │  │
│  └─────────────┘  └─────────────┘  └─────────────────────────┘  │
└─────────────────────────────────────────────────────────────────┘
```

## Components

### 1. React Native Client

**Location:** `app/voice-call.tsx`, `hooks/useLiveKitRoom.ts`

**Dependencies:**
- `@livekit/react-native` - LiveKit React Native SDK
- `@livekit/react-native-webrtc` - WebRTC for React Native
- `expo-av` - Audio session management

**Key Features:**
- Connects to LiveKit room with JWT token
- Manages audio session (activates speaker mode)
- Handles microphone permissions
- Displays connection state and transcription

### 2. LiveKit Cloud

**Project:** `live-kit-demo-70txlh6a`
**Agent ID:** `CA_Yd3qcuYEVKKE`

**Configuration:**
- Auto-scaling agent workers
- Managed STT/TTS through inference endpoints
- Built-in noise cancellation

**Getting Tokens:**
```typescript
// From WellNuo backend
const response = await fetch('/api/livekit/token', {
  method: 'POST',
  body: JSON.stringify({ roomName, userName })
});
const { token, url } = await response.json();
```

### 3. Julia AI Agent (Python)

**Location:** `julia-agent/julia-ai/src/agent.py`

**Stack:**
- LiveKit Agents SDK
- Deepgram Nova-2 (STT)
- Deepgram Aura Asteria (TTS - female voice)
- Silero VAD (Voice Activity Detection)
- Custom WellNuo LLM (voice_ask API)

## Setup & Deployment

### Prerequisites

1. **LiveKit Cloud Account**
   - Sign up at https://cloud.livekit.io/
   - Create a project
   - Get API credentials

2. **LiveKit CLI**
   ```bash
   # macOS
   brew install livekit-cli

   # Login
   lk cloud auth
   ```

### Agent Deployment

1. **Navigate to agent directory:**
   ```bash
   cd julia-agent/julia-ai
   ```

2. **Install dependencies:**
   ```bash
   uv sync
   ```

3. **Configure environment:**
   ```bash
   cp .env.example .env.local
   # Add LIVEKIT_URL, LIVEKIT_API_KEY, LIVEKIT_API_SECRET
   ```

4. **Local development:**
   ```bash
   uv run python src/agent.py dev
   ```

5. **Deploy to LiveKit Cloud:**
   ```bash
   lk agent deploy
   ```

### React Native Setup

1. **Install packages:**
   ```bash
   npm install @livekit/react-native @livekit/react-native-webrtc
   ```

2. **iOS permissions (Info.plist):**
   ```xml
   <key>NSMicrophoneUsageDescription</key>
   <string>WellNuo needs microphone access for voice calls with Julia AI</string>
   ```

3. **Pod install:**
   ```bash
   cd ios && pod install
   ```

## Flow Diagram

```
User opens Voice tab
        │
        ▼
Request microphone permission
        │
        ├─ Denied → Show error
        │
        ▼
Get LiveKit token from WellNuo API
        │
        ▼
Connect to LiveKit room
        │
        ▼
Agent joins automatically (LiveKit Cloud)
        │
        ▼
Agent sends greeting (TTS)
        │
        ▼
User speaks → STT → WellNuo API → Response → TTS
        │
        ▼
User ends call → Disconnect from room
```

## API Integration

### WellNuo voice_ask API

The agent uses WellNuo's `voice_ask` API to get contextual responses about the beneficiary.

**Endpoint:** `https://eluxnetworks.net/function/well-api/api`

**Authentication:**
```python
data = {
    "function": "credentials",
    "clientId": "001",
    "user_name": WELLNUO_USER,
    "ps": WELLNUO_PASSWORD,
    "nonce": str(random.randint(0, 999999)),
}
```

**Voice Ask:**
```python
data = {
    "function": "voice_ask",
    "clientId": "001",
    "user_name": WELLNUO_USER,
    "token": token,
    "question": user_message,
    "deployment_id": DEPLOYMENT_ID,
}
```

## Troubleshooting

### Common Issues

1. **No audio playback on iOS**
   - Check audio session configuration
   - Ensure `expo-av` is properly configured
   - Test on real device (simulator has audio limitations)

2. **Microphone not working**
   - Verify permissions in Info.plist
   - Check if user granted permission
   - Real device required for full audio testing

3. **Agent not responding**
   - Check agent logs: `lk agent logs`
   - Verify LIVEKIT credentials
   - Check WellNuo API connectivity

4. **Connection fails**
   - Verify token is valid
   - Check network connectivity
   - Ensure LiveKit URL is correct

### Debugging

```bash
# View agent logs
lk agent logs

# View specific deployment logs
lk agent logs --version v20260119031418

# Check agent status
lk agent list
```

## Environment Variables

### Agent (.env.local)
```
LIVEKIT_URL=wss://live-kit-demo-70txlh6a.livekit.cloud
LIVEKIT_API_KEY=your-api-key
LIVEKIT_API_SECRET=your-api-secret
WELLNUO_USER=anandk
WELLNUO_PASSWORD=anandk_8
DEPLOYMENT_ID=21
```

### React Native (via WellNuo backend)
Token generation handled server-side for security.

## Status

**Current State:** WIP - Not tested on real device

**Working:**
- Agent deploys to LiveKit Cloud
- Agent connects to rooms
- STT/TTS pipeline configured
- WellNuo API integration
- React Native UI

**Needs Testing:**
- Real device microphone capture
- Audio playback on physical iOS device
- Full conversation loop end-to-end
- Token refresh/expiration handling