# WiFi Network Setup Guide

## Overview

The LEDMatrix WiFi system provides automatic network configuration with intelligent failover to Access Point (AP) mode. When your Raspberry Pi loses network connectivity, it automatically creates a WiFi access point for easy configuration—ensuring you can always connect to your device.

### Key Features

- **Automatic AP Mode**: Creates a WiFi access point when network connection is lost
- **Intelligent Failover**: Only activates after a grace period to prevent false positives
- **Dual Connectivity**: Supports both WiFi and Ethernet with automatic priority management
- **Web Interface**: Configure WiFi through an easy-to-use web interface
- **Network Scanning**: Scan and connect to available WiFi networks
- **Secure Storage**: WiFi credentials stored securely

---

## Quick Start

### Accessing WiFi Setup

**If not connected to WiFi:**
1. Wait 90 seconds after boot (AP mode activation grace period)
2. Connect to WiFi network **LEDMatrix-Setup** (an open network: no
   password)
3. Open browser to: `http://192.168.4.1:5000`
4. Open the **WiFi** tab
5. Scan, select your network, and connect

**If already connected:**
1. Open browser to: `http://your-pi-ip:5000`
2. Navigate to the WiFi tab
3. Configure as needed

---

## Installation

### Prerequisites

The following packages are required:
- **hostapd** - Access point software
- **dnsmasq** - DHCP server for AP mode
- **NetworkManager** - WiFi management

### Install WiFi Monitor Service

```bash
cd /home/ledpi/LEDMatrix
sudo ./scripts/install/install_wifi_monitor.sh
```

This script will:
- Check for required packages and offer to install them
- Create the systemd service file
- Enable and start the WiFi monitor service
- Configure the service to start on boot

### Verify Installation

```bash
# Check service status
sudo systemctl status ledmatrix-wifi-monitor

# Run verification script
./scripts/verify_wifi_setup.sh
```

---

## Configuration

### Configuration File

WiFi settings are stored in `config/wifi_config.json`:

```json
{
  "ap_ssid": "LEDMatrix-Setup",
  "ap_channel": 7,
  "auto_enable_ap_mode": true
}
```

### Configuration Options

| Setting | Default | Description |
|---------|---------|-------------|
| `ap_ssid` | `LEDMatrix-Setup` | Network name broadcast in AP mode |
| `ap_channel` | `7` | WiFi channel (1, 6, or 11 are non-overlapping) |
| `auto_enable_ap_mode` | `true` | Automatically enable AP mode when both WiFi and Ethernet are disconnected |

### Auto-Enable AP Mode Behavior

**When enabled (`true` - recommended):**
- AP mode activates automatically after 90-second grace period
- Only when both WiFi AND Ethernet are disconnected
- Automatically disables when either WiFi or Ethernet connects
- Best for portable devices or unreliable network environments

**When disabled (`false`):**
- AP mode must be manually enabled through web interface
- Prevents unnecessary AP activation
- Best for devices with stable network connections

---

## Using WiFi Setup

### Connecting to a WiFi Network

**Via Web Interface:**
1. Navigate to the **WiFi** tab
2. Click **Scan** to search for networks
3. Select a network from the dropdown (or enter SSID manually)
4. Enter the WiFi password (leave empty for open networks)
5. Click **Connect**
6. System will attempt connection
7. AP mode automatically disables once connected

**Via API:**
```bash
# Scan for networks
curl "http://your-pi-ip:5000/api/v3/wifi/scan"

# Connect to network
curl -X POST http://your-pi-ip:5000/api/v3/wifi/connect \
  -H "Content-Type: application/json" \
  -d '{"ssid": "YourNetwork", "password": "your-password"}'
```

### Manual AP Mode Control

**Via Web Interface:**
- **Enable AP Mode**: Click "Enable AP Mode" button (only when WiFi/Ethernet disconnected)
- **Disable AP Mode**: Click "Disable AP Mode" button (when AP is active)

**Via API:**
```bash
# Enable AP mode
curl -X POST http://your-pi-ip:5000/api/v3/wifi/ap/enable

# Disable AP mode
curl -X POST http://your-pi-ip:5000/api/v3/wifi/ap/disable
```

**Note:** Manual enable still requires both WiFi and Ethernet to be disconnected.

---

## Understanding AP Mode Failover

### How the Grace Period Works

The system uses a **grace period mechanism** to prevent false positives from temporary network hiccups:

```
Check Interval: 30 seconds (default)
Required Checks: 3 consecutive
Grace Period: 90 seconds total
```

**Timeline Example:**
```
Time 0s:   WiFi disconnects
Time 30s:  Check 1 - Disconnected (counter = 1)
Time 60s:  Check 2 - Disconnected (counter = 2)
Time 90s:  Check 3 - Disconnected (counter = 3) → AP MODE ENABLED
```

If WiFi or Ethernet reconnects at any point, the counter resets to 0.

### Why Grace Period is Important

Without a grace period, AP mode would activate during:
- Brief network hiccups
- Router reboots
- Temporary signal interference
- NetworkManager reconnection attempts

The 90-second grace period ensures AP mode only activates during **sustained disconnection**.

### Connection Priority

The system checks connections in this order:
1. **WiFi Connection** (highest priority)
2. **Ethernet Connection** (fallback)
3. **AP Mode** (last resort - only when both WiFi and Ethernet disconnected)

### Behavior Summary

| WiFi Status | Ethernet Status | Auto-Enable | AP Mode Behavior |
|-------------|-----------------|-------------|------------------|
| Any | Any | `false` | Manual enable only |
| Connected | Any | `true` | Disabled |
| Disconnected | Connected | `true` | Disabled (Ethernet available) |
| Disconnected | Disconnected | `true` | Auto-enabled after 90s |

---

## Access Point Configuration

### AP Mode Settings

- **SSID**: `LEDMatrix-Setup` (configurable via `ap_ssid`)
- **Network**: open (no password). Both AP paths create an open network
  (`_create_hostapd_config()` and `_enable_ap_mode_nmcli_hotspot()` in
  `src/wifi_manager.py`); an `ap_password` key in `wifi_config.json` is not
  read
- **IP Address**: 192.168.4.1
- **DHCP Range**: 192.168.4.2 – 192.168.4.20
- **Channel**: 7 (configurable via `ap_channel`)

### Accessing Services in AP Mode

When AP mode is active:
- Web Interface: `http://192.168.4.1:5000`
- SSH: `ssh ledpi@192.168.4.1`
- Captive portal may automatically redirect browsers

---

## Best Practices

### Security Recommendations

**1. Keep AP mode short-lived:**
The setup network is open, so anyone nearby can join it and reach the web
interface while it is up. AP mode only comes up when WiFi and Ethernet are
both disconnected (after the 90 second grace period) and goes down again once
the Pi is connected; in a public area, consider setting
`auto_enable_ap_mode` to `false` and enabling AP mode by hand when needed.

**2. Use Non-Overlapping WiFi Channels:**
- Channels 1, 6, 11 are non-overlapping (2.4GHz)
- Choose a channel that doesn't conflict with your primary network
- Example: If primary uses channel 1, use channel 11 for AP mode

**3. Secure WiFi Credentials:**
```bash
sudo chmod 600 config/wifi_config.json
```

### Network Configuration Tips

**Multiple Networks:**

NetworkManager remembers every network you connect to and rejoins whichever is
in range; list them with `nmcli connection show`. LEDMatrix itself does not
store WiFi passwords.

**Adjust Check Interval:**

Edit the systemd service file to change grace period:
```bash
sudo systemctl edit ledmatrix-wifi-monitor
```

Add:
```ini
[Service]
ExecStart=
ExecStart=/usr/bin/python3 /path/to/LEDMatrix/scripts/utils/wifi_monitor_daemon.py --interval 20
```

**Note:** Interval affects grace period:
- 20-second interval = 60-second grace period (3 × 20)
- 30-second interval = 90-second grace period (3 × 30) ← Default
- 60-second interval = 180-second grace period (3 × 60)

---

## Configuration Scenarios

### Scenario 1: Portable Device with Auto-Failover (Recommended)

**Use Case:** Device may lose WiFi connection

**Configuration:**
```json
{
  "auto_enable_ap_mode": true
}
```

**Behavior:**
- AP mode activates automatically after 90 seconds of disconnection
- Always provides a way to connect
- Best for devices that move or have unreliable WiFi

### Scenario 2: Stable Network Connection

**Use Case:** Ethernet or reliable WiFi connection

**Configuration:**
```json
{
  "auto_enable_ap_mode": false
}
```

**Behavior:**
- AP mode must be manually enabled
- Prevents unnecessary activation
- Best for stationary devices with stable connections

### Scenario 3: Ethernet Primary with WiFi Backup

**Use Case:** Primary Ethernet, WiFi as backup

**Configuration:**
```json
{
  "auto_enable_ap_mode": true
}
```

**Behavior:**
- Ethernet connection prevents AP mode activation
- If Ethernet disconnects, WiFi is attempted
- If both disconnect, AP mode activates after grace period
- Best for devices with both Ethernet and WiFi

---

## Troubleshooting

### AP Mode Not Activating

**Check 1: Auto-Enable Setting**
```bash
cat config/wifi_config.json | grep auto_enable_ap_mode
```
Should show `"auto_enable_ap_mode": true`

**Check 2: Service Status**
```bash
sudo systemctl status ledmatrix-wifi-monitor
```
Service should be `active (running)`

**Check 3: Grace Period**
- Wait at least 90 seconds after disconnection
- Check logs: `sudo journalctl -u ledmatrix-wifi-monitor -f`

**Check 4: Ethernet Connection**
- If Ethernet is connected, AP mode won't activate
- Verify: `nmcli device status`
- Disconnect Ethernet to test AP mode

**Check 5: Required Packages**
```bash
# Verify hostapd is installed
which hostapd

# Verify dnsmasq is installed
which dnsmasq
```

### Cannot Access AP Mode

**Check 1: AP Mode Active**
```bash
sudo systemctl status hostapd
sudo systemctl status dnsmasq
```
Both should be running

**Check 2: Network Interface**
```bash
ip addr show wlan0
```
Should show IP `192.168.4.1`

**Check 3: WiFi Interface Available**
```bash
ip link show wlan0
```
Interface should exist

**Check 4: Try Manual Enable**
- Use web interface: WiFi tab → Enable AP Mode
- Or via API: `curl -X POST http://localhost:5000/api/v3/wifi/ap/enable`

### Cannot Connect to WiFi Network

**Check 1: Verify Credentials**
- Ensure SSID and password are correct
- Check for hidden networks (manual SSID entry required)

**Check 2: Check Logs**
```bash
# WiFi monitor logs
sudo journalctl -u ledmatrix-wifi-monitor -f

# NetworkManager logs
sudo journalctl -u NetworkManager -n 50
```

**Check 3: Network Compatibility**
- Verify network is 2.4GHz (5GHz may not be supported on all Pi models)
- Check if network requires special authentication

### AP Mode Not Disabling After WiFi Connect

**Check 1: WiFi Connection Status**
```bash
nmcli device status
```

**Check 2: Manually Disable**
- Use web interface: WiFi tab → Disable AP Mode
- Or restart service: `sudo systemctl restart ledmatrix-wifi-monitor`

**Check 3: Check Logs**
```bash
sudo journalctl -u ledmatrix-wifi-monitor -n 50
```

### AP Mode Activating Unexpectedly

**Check 1: Network Stability**
- Verify WiFi connection is stable
- Check router status
- Check signal strength

**Check 2: Disable Auto-Enable**
```bash
nano config/wifi_config.json
# Change: "auto_enable_ap_mode": false
sudo systemctl restart ledmatrix-wifi-monitor
```

**Check 3: Increase Grace Period**
- Edit service file to increase check interval
- Longer interval = longer grace period
- See "Best Practices" section above

---

## Monitoring and Diagnostics

### Check WiFi Status

**Via Python:**
```python
from src.wifi_manager import WiFiManager

wm = WiFiManager()
status = wm.get_wifi_status()

print(f'Connected: {status.connected}')
print(f'SSID: {status.ssid}')
print(f'IP Address: {status.ip_address}')
print(f'AP Mode Active: {status.ap_mode_active}')
print(f'Auto-Enable: {wm.config.get("auto_enable_ap_mode", False)}')
```

**Via NetworkManager:**
```bash
# View device status
nmcli device status

# View connections
nmcli connection show

# View available WiFi networks
nmcli device wifi list
```

### View Service Logs

```bash
# Real-time logs
sudo journalctl -u ledmatrix-wifi-monitor -f

# Recent logs (last 50 lines)
sudo journalctl -u ledmatrix-wifi-monitor -n 50

# Logs from specific time
sudo journalctl -u ledmatrix-wifi-monitor --since "1 hour ago"
```

### Run Verification Script

```bash
cd /home/ledpi/LEDMatrix
./scripts/verify_wifi_setup.sh
```

Checks:
- Required packages installed
- WiFi monitor service running
- Configuration files valid
- WiFi interface available
- Current connection status
- AP mode status

---

## Service Management

### Useful Commands

```bash
# Check service status
sudo systemctl status ledmatrix-wifi-monitor

# Start the service
sudo systemctl start ledmatrix-wifi-monitor

# Stop the service
sudo systemctl stop ledmatrix-wifi-monitor

# Restart the service
sudo systemctl restart ledmatrix-wifi-monitor

# View logs
sudo journalctl -u ledmatrix-wifi-monitor -f

# Disable service from starting on boot
sudo systemctl disable ledmatrix-wifi-monitor

# Enable service to start on boot
sudo systemctl enable ledmatrix-wifi-monitor
```

---

## API Reference

The WiFi setup feature exposes the following API endpoints:

| Method | Endpoint | Description |
|--------|----------|-------------|
| GET | `/api/v3/wifi/status` | Get current WiFi connection status |
| GET | `/api/v3/wifi/scan` | Scan for available WiFi networks |
| POST | `/api/v3/wifi/connect` | Connect to a WiFi network |
| POST | `/api/v3/wifi/ap/enable` | Enable access point mode |
| POST | `/api/v3/wifi/ap/disable` | Disable access point mode |
| GET | `/api/v3/wifi/ap/auto-enable` | Get auto-enable setting |
| POST | `/api/v3/wifi/ap/auto-enable` | Set auto-enable setting |

### Example Usage

```bash
# Get WiFi status
curl "http://your-pi-ip:5000/api/v3/wifi/status"

# Scan for networks
curl "http://your-pi-ip:5000/api/v3/wifi/scan"

# Connect to network
curl -X POST http://your-pi-ip:5000/api/v3/wifi/connect \
  -H "Content-Type: application/json" \
  -d '{"ssid": "MyNetwork", "password": "mypassword"}'

# Enable AP mode
curl -X POST http://your-pi-ip:5000/api/v3/wifi/ap/enable

# Check auto-enable setting
curl "http://your-pi-ip:5000/api/v3/wifi/ap/auto-enable"

# Set auto-enable
curl -X POST http://your-pi-ip:5000/api/v3/wifi/ap/auto-enable \
  -H "Content-Type: application/json" \
  -d '{"auto_enable_ap_mode": true}'
```

---

## Technical Details

### WiFi Monitor Daemon

The WiFi monitor daemon (`wifi_monitor_daemon.py`) runs as a background service that:

1. Checks WiFi and Ethernet connection status every 30 seconds (configurable)
2. Maintains disconnected check counter for grace period
3. Automatically enables AP mode when:
   - `auto_enable_ap_mode` is enabled AND
   - Both WiFi and Ethernet disconnected AND
   - Grace period elapsed (3 consecutive checks)
4. Automatically disables AP mode when WiFi or Ethernet connects
5. Logs all state changes

### WiFi Detection Methods

The WiFi manager tries multiple methods:

1. **NetworkManager (nmcli)** - Preferred method
2. **iwconfig** - Fallback for systems without NetworkManager

### Network Scanning Methods

1. **nmcli** - Fast, preferred method
2. **iwlist** - Fallback for older systems

### Access Point Implementation

- Uses `hostapd` for WiFi access point functionality
- Uses `dnsmasq` for DHCP and DNS services
- Configures wlan0 interface with IP 192.168.4.1
- Provides DHCP range: 192.168.4.2-20
- Captive portal with DNS redirection

---

## Related Documentation

- [WEB_INTERFACE_GUIDE.md](WEB_INTERFACE_GUIDE.md) - Using the web interface
- [TROUBLESHOOTING.md](TROUBLESHOOTING.md) - General troubleshooting
- [GETTING_STARTED.md](GETTING_STARTED.md) - Initial setup guide