fix: resolve WiFi device discovery and connection issues

CLAUDE.md

@@ -170,13 +170,25 @@ catch (Exception ex)
 ## Device Communication
 
 The application communicates with DAQiFi devices using:
-- UDP for device discovery
-- TCP for data streaming and commands
-- Protocol Buffers for message serialization
-
-Key classes:
-- `DaqifiDeviceFinder.cs` - Handles device discovery
-- `WiFiDevice` - Manages WiFi device connections
+- **UDP for device discovery**: Port 30303 (broadcast queries and responses)
+- **TCP for data streaming**: Port varies by device (extracted from discovery response)
+- **Protocol Buffers**: Message serialization for both UDP and TCP
+
+### Port Configuration
+- **UDP Discovery Port**: 30303 (used in `DaqifiDeviceFinder` and firewall rules)
+- **TCP Data Port**: Device-specific (e.g., 9760) - discovered from `message.DevicePort` in protobuf response
+- **Manual IP connections**: Must use the same TCP port as discovered devices
+
+### Network Requirements
+- **Firewall Rule**: UDP port 30303 must be allowed for device discovery
+- **Admin Privileges**: Required for automatic firewall configuration
+- **Network Interface**: Application and device must be on same subnet for UDP broadcast discovery
+- **Virtual Machines**: Use bridged networking mode, not NAT/shared network
+
+### Key Classes
+- `DaqifiDeviceFinder.cs` - Handles UDP device discovery on port 30303
+- `DaqifiStreamingDevice.cs` - Manages TCP connections to devices
+- `FirewallManager.cs` - Configures Windows Firewall for UDP port 30303
 - Protocol buffer messages defined in `.proto` files
 
 ## Database
@@ -219,11 +231,13 @@ public void InitializeFirewallRules()
 ## Common Tasks
 
 When working on:
-- **Device connectivity**: Check `/Device/` directory
+- **Device connectivity**: Check `/Device/` directory and ensure network configuration
 - **UI changes**: Update both View and ViewModel following MVVM
 - **Data persistence**: Use Entity Framework patterns
 - **Protocol changes**: Update `.proto` files and regenerate
-- **Firewall/Network**: Ensure admin privileges handled properly
+- **Firewall/Network**: Ensure admin privileges handled properly, verify ports match
+- **WiFi Discovery Issues**: Check network interface detection and port configuration
+- **Manual IP Connections**: Ensure TCP port matches what device discovery reports
 - **New features**: Add unit tests with 80% coverage minimum
 
 ## Performance Considerations

Daqifi.Desktop.Test/Configuration/FirewallConfigurationTests.cs

@@ -51,7 +51,7 @@ public void InitializeFirewallRules_WhenRuleDoesNotExist_CreatesNewRule()
         FirewallConfiguration.InitializeFirewallRules();
 
         // Assert
-        _mockFirewallHelper.Verify(f => f.CreateUdpRule(It.IsAny<string>(), It.IsAny<string>(), 21234), Times.Once);
+        _mockFirewallHelper.Verify(f => f.CreateUdpRule(It.IsAny<string>(), It.IsAny<string>(), 30303), Times.Once);
         _mockMessageBoxService.Verify(m => m.Show(It.IsAny<string>(), It.IsAny<string>(), It.IsAny<MessageBoxButton>(), It.IsAny<MessageBoxImage>()), Times.Never);
     }
 
@@ -81,7 +81,7 @@ public void InitializeFirewallRules_WhenCreatingRuleThrowsException_ShowsErrorMe
         // Arrange
         _mockAdminChecker.Setup(c => c.IsCurrentUserAdmin()).Returns(true);
         _mockFirewallHelper.Setup(f => f.RuleExists("DAQiFi Desktop")).Returns(false);
-        _mockFirewallHelper.Setup(f => f.CreateUdpRule(It.IsAny<string>(), It.IsAny<string>(), 21234))
+        _mockFirewallHelper.Setup(f => f.CreateUdpRule(It.IsAny<string>(), It.IsAny<string>(), 30303))
             .Throws(new InvalidOperationException("Test exception"));
 
         // Act

Daqifi.Desktop/Configuration/FirewallManager.cs

@@ -72,8 +72,8 @@ public static void InitializeFirewallRules()
                 return;
             }
 
-            // Create new rule with specific UDP port (21234 is DAQiFi's discovery port)
-            _firewallHelper.CreateUdpRule(RuleName, appPath, 21234);
+            // Create new rule with specific UDP port (30303 is DAQiFi's UDP discovery port)
+            _firewallHelper.CreateUdpRule(RuleName, appPath, 30303);
         }
         catch (Exception ex)
         {

Daqifi.Desktop/Device/WiFiDevice/DaqifiDeviceFinder.cs

@@ -73,7 +73,7 @@ public override void Run()
                          }
                          catch (SocketException sockEx)
                          {
-                             AppLogger.Warning($"Error sending broadcast to {endpoint}, {sockEx}");
+                             AppLogger.Warning($"Error sending broadcast to {endpoint} (SocketError={sockEx.SocketErrorCode}): {sockEx.Message}");
                          }
                     }
                     Thread.Sleep(1000);
@@ -194,6 +194,7 @@ public void NotifyDeviceRemoved(object sender, IDevice device)
     private List<IPEndPoint> GetAllBroadcastEndpoints(int port)
     {
         var endpoints = new List<IPEndPoint>();
+
         foreach (var networkInterface in NetworkInterface.GetAllNetworkInterfaces())
         {
             if (networkInterface.OperationalStatus != OperationalStatus.Up ||
@@ -233,16 +234,21 @@ private List<IPEndPoint> GetAllBroadcastEndpoints(int port)
                 }
 
                 var broadcastAddress = new IPAddress(broadcastBytes);
-
-                endpoints.Add(new IPEndPoint(broadcastAddress, port));
-
+                var endpoint = new IPEndPoint(broadcastAddress, port);
+                endpoints.Add(endpoint);
+                
                 break;
             }
         }
 
-        AppLogger.Information(endpoints.Count == 0
-            ? "Could not find any suitable network interfaces for DAQiFi discovery broadcast."
-            : $"DAQiFi Discovery broadcasting to: {string.Join(", ", endpoints.Select(ep => ep.Address.ToString()))}");
+        if (endpoints.Count == 0)
+        {
+            AppLogger.Warning("Could not find any suitable network interfaces for DAQiFi discovery broadcast.");
+        }
+        else
+        {
+            AppLogger.Information($"DAQiFi discovery will broadcast to {endpoints.Count} network endpoint(s)");
+        }
 
         return endpoints;
     }

Daqifi.Desktop/Device/WiFiDevice/DaqifiStreamingDevice.cs

@@ -39,12 +39,34 @@ public override bool Connect()
         {
             Client = new TcpClient();
             var result = Client.BeginConnect(IpAddress, Port, null, null);
-            var success = result.AsyncWaitHandle.WaitOne(TimeSpan.FromSeconds(5));
-
-            if (!success)
+            var waitHandle = result.AsyncWaitHandle;
+
+            try
+            {
+                var success = waitHandle.WaitOne(TimeSpan.FromSeconds(5));
+
+                if (!success)
+                {
+                    AppLogger.Error($"Timeout connecting to DAQiFi device at {IpAddress}:{Port}");
+                    Client?.Close();
+                    return false;
+                }
+
+                // Complete the asynchronous connection
+                try
+                {
+                    Client.EndConnect(result);
+                }
+                catch (SocketException ex)
+                {
+                    AppLogger.Error(ex, $"Failed to connect to DAQiFi device at {IpAddress}:{Port}");
+                    Client?.Close();
+                    return false;
+                }
+            }
+            finally
             {
-                AppLogger.Error("Timeout connecting to DAQiFi Device.");
-                return false;
+                waitHandle?.Close();
             }
 
             MessageProducer = new MessageProducer(Client.GetStream());

Daqifi.Desktop/ViewModels/ConnectionDialogViewModel.cs

@@ -119,7 +119,8 @@ private async Task ConnectManualWifiAsync()
         var deviceInfo = new DeviceInfo
         {
             IpAddress = ManualIpAddress,
-            DeviceName = "Manual IP Device"
+            DeviceName = "Manual IP Device",
+            Port = 9760 // Common DAQiFi TCP data port - TODO: make configurable or discover dynamically
         };
 
         var device = new DaqifiStreamingDevice(deviceInfo);

README.md

@@ -56,6 +56,25 @@ DatabaseLogger->>Database:Bulk Insert Buffer
 - Uses [Wix Toolset](https://wixtoolset.org/)
 - Separate solution `Daqifi.Desktop.Setup`
 
+## WiFi Device Connectivity
+
+DAQiFi Desktop discovers and connects to DAQiFi devices over WiFi using UDP broadcasts and TCP connections.
+
+### Network Requirements
+- **Same Network**: Computer and DAQiFi device must be on the same network/subnet
+- **Firewall**: UDP port 30303 must be allowed (configured automatically with admin privileges)
+- **Virtual Machines**: Use bridged networking mode for VM environments
+
+### Troubleshooting WiFi Discovery
+1. **Run as Administrator** - Required for automatic firewall configuration
+2. **Check Network Connection** - Ensure computer and device are on same WiFi network
+3. **Verify Connectivity** - Test with `ping <device-ip>` from command prompt
+4. **Manual Connection** - Use manual IP connection if discovery fails
+
+### Port Configuration
+- **UDP Discovery**: Port 30303 (device discovery broadcasts)
+- **TCP Data**: Device-specific port (varies by device, typically 9760)
+
 ## Contribution
 
 Please read [Contributing Guidelines](CONTRIBUTING.md) before contributing.