# TWP Softphone — Mobile App

Flutter-based VoIP softphone client for the Twilio WordPress Plugin. Uses the Twilio Voice SDK (WebRTC) to make and receive calls via the Android Telecom framework.

## Requirements

- Flutter 3.29+ (tested with 3.41.4)
- Android device/tablet (API 26+)
- TWP WordPress plugin installed and configured on server
- Twilio account with Voice capability

## Quick Start

```bash
cd mobile
flutter pub get
flutter build apk --debug
adb install build/app/outputs/flutter-apk/app-debug.apk
```

## Server Setup

The app connects to your WordPress site running the TWP plugin. The server must have:

1. **TWP Plugin** installed and activated
2. **Twilio credentials** configured (Account SID, Auth Token)
3. **At least one Twilio phone number** purchased
4. **A WordPress user** with agent permissions

### SSE (Server-Sent Events) — Apache + PHP-FPM

The app uses SSE for real-time updates (queue changes, agent status). On Apache with PHP-FPM, `mod_proxy_fcgi` buffers output by default, which breaks SSE streaming.

**Fix** — Create a config file on the web server:

```bash
echo 'ProxyPassMatch "^/wp-json/twilio-mobile/v1/stream/events$" "unix:/run/php-fpm/www.sock|fcgi://localhost/path/to/wordpress/index.php" flushpackets=on' > /etc/httpd/conf.d/twp-sse.conf
httpd -t && systemctl restart httpd
```

> **Adjust the paths:**
> - Socket path must match your PHP-FPM config (check `grep fcgi /etc/httpd/conf.d/php.conf`)
> - Document root must match your WordPress installation path

**Diagnosis** — If the green connection dot stays red:

```bash
# Check current PHP-FPM proxy config
grep -r "fcgi\|php-fpm" /etc/httpd/conf.d/

# Check if flushpackets is configured
grep -r "flushpackets" /etc/httpd/conf.d/

# Test SSE endpoint (should stream data continuously, not hang)
curl -N -H "Authorization: Bearer YOUR_TOKEN" \
  https://your-site.com/wp-json/twilio-mobile/v1/stream/events
```

**Notes:**
- `flushpackets=on` is a `ProxyPassMatch` directive — it **cannot** go in `.htaccess`
- If using **nginx** instead of Apache, the `X-Accel-Buffering: no` header (already in the PHP code) handles this automatically
- The app automatically falls back to 5-second polling if SSE fails, so the app still works without this config — just with higher latency

## App Setup (Android)

### First Launch

1. Open the app and enter your server URL (e.g., `https://phone.cloud-hosting.io`)
2. Log in with your WordPress credentials
3. Grant permissions when prompted:
   - Microphone (required for calls)
   - Phone/Call (required for Android Telecom integration)

### Phone Account

Android requires a registered and **enabled** phone account for VoIP apps. The app registers automatically, but enabling must be done manually:

1. If prompted, tap **"Open Settings"** to go to Android's Phone Account settings
2. Find **"TWP Softphone"** in the list and toggle it **ON**
3. Return to the app

If you skipped this step, tap the orange warning card on the dashboard.

> **Path:** Settings → Apps → Default apps → Phone → Calling accounts → TWP Softphone

### Making Calls

1. Tap the phone FAB (bottom right) to open the dialer
2. Enter the phone number
3. Caller ID is auto-selected from your Twilio numbers
4. Tap **Call** — the Android system call screen (InCallUI) handles the active call

### Receiving Calls

Incoming calls appear via Android's native call UI. Answer/reject using the standard Android interface.

> **Note:** FCM push notifications are required for receiving calls when the app is in the background. This requires `google-services.json` in `android/app/`.

### Queue Management

- View assigned queues on the dashboard
- Tap a queue with waiting calls to see callers
- Tap **Accept** to take a call from the queue

### Agent Status

Toggle between **Available**, **Busy**, and **Offline** using the status bar at the top of the dashboard.

## Development

### Project Structure

```
lib/
├── config/          # App configuration
├── models/          # Data models (CallInfo, QueueState, AgentStatus, User)
├── providers/       # State management (AuthProvider, CallProvider, AgentProvider)
├── screens/         # UI screens (Login, Dashboard, Settings, ActiveCall)
├── services/        # API/SDK services (VoiceService, SseService, ApiClient, AuthService)
├── widgets/         # Reusable widgets (Dialpad, QueueCard, AgentStatusToggle)
└── main.dart        # App entry point
```

### Running Tests

```bash
flutter test
```

34 tests covering CallInfo, QueueState, and CallProvider.

### Building

```bash
# Debug APK
flutter build apk --debug

# Release APK (requires signing config)
flutter build apk --release
```

### ADB Deployment (WiFi)

```bash
# Connect to device
adb connect DEVICE_IP:PORT

# Install
adb install -r build/app/outputs/flutter-apk/app-debug.apk

# Launch
adb shell am start -n io.cloudhosting.twp.twp_softphone/.MainActivity

# View logs
adb logcat -s flutter
```

### Key Dependencies

| Package | Purpose |
|---------|---------|
| `twilio_voice` | Twilio Voice SDK (WebRTC calling) |
| `provider` | State management |
| `dio` | HTTP client (REST API, SSE) |
| `firebase_messaging` | FCM push for incoming calls |
| `flutter_secure_storage` | Secure token storage |

## Troubleshooting

| Problem | Solution |
|---------|----------|
| Green dot stays red | SSE buffering — see [Server Setup](#sse-server-sent-events--apache--php-fpm) |
| "No registered phone account" | Enable phone account in Android Settings (see [Phone Account](#phone-account)) |
| Calls fail with "Invalid callerId" | Server webhook needs phone number validation — check `handle_browser_voice` in `class-twp-webhooks.php` |
| App hangs on login | Check server is reachable: `curl https://your-site.com/wp-json/twilio-mobile/v1/auth/login` |
| No incoming calls | Ensure FCM is configured (`google-services.json`) and phone account is enabled |