fix: RGB connection — force IPv4 (127.0.0.1) instead of localhost

ROOT CAUSE: OpenRGB server binds 0.0.0.0 (IPv4 only) but FANZi connected

via 'localhost' which resolves to ::1 (IPv6) on Windows — connection fails.

Confirmed with standalone test: OpenRGB.NET connects fine to 127.0.0.1:6742,

finds ASUS PRIME Z590-P with 2 LEDs, 3 zones, sets them to blue successfully.

Author: AntwerpDesignsIonity

src/Fanzi.FanControl/Services/OpenRgbService.cs

@@ -51,8 +51,13 @@ public Task<bool> TryConnectAsync(
                     ServerVersion = "Not connected";
                     ModeSwitchStatus = "";
 
+                    // Force IPv4 — OpenRGB server only binds 0.0.0.0, and
+                    // "localhost" resolves to ::1 (IPv6) on Windows which fails.
+                    string connectHost = host.Equals("localhost", StringComparison.OrdinalIgnoreCase)
+                        ? "127.0.0.1" : host;
+
                     var client = new OpenRgbClient(
-                        ip:                     host,
+                        ip:                     connectHost,
                         port:                   port,
                         name:                   "FANZI",
                         autoConnect:            false,

src/Fanzi.FanControl/ViewModels/RgbControlViewModel.cs

@@ -74,7 +74,7 @@ public sealed partial class RgbControlViewModel : ViewModelBase, IDisposable
     public string ConnectButtonText          => IsConnecting ? "Connecting…" : "Connect";
 
     [ObservableProperty]
-    private string _openRgbHost = "localhost";
+    private string _openRgbHost = "127.0.0.1";
 
     [ObservableProperty]
     private int _openRgbPort = 6742;

src/Fanzi.OpenRgbTest/Fanzi.OpenRgbTest.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net10.0</TargetFramework>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+  <ItemGroup>
+    <PackageReference Include="OpenRGB.NET" Version="3.1.1" />
+  </ItemGroup>
+</Project>

src/Fanzi.OpenRgbTest/Program.cs

@@ -0,0 +1,69 @@
+using OpenRGB.NET;
+using System;
+
+try
+{
+    Console.WriteLine("=== OpenRGB Connection Test ===");
+    Console.WriteLine($"Connecting to localhost:6742...");
+
+    var client = new OpenRgbClient(
+        ip: "127.0.0.1",
+        port: 6742,
+        name: "FANZI-TEST",
+        autoConnect: false,
+        protocolVersionNumber: 4);
+
+    client.Connect();
+    Console.WriteLine("Connect() succeeded!");
+
+    Console.WriteLine("Connect() OK — fetching devices...");
+
+    var devices = client.GetAllControllerData();
+    Console.WriteLine($"Found {devices.Length} device(s):");
+
+    for (int i = 0; i < devices.Length; i++)
+    {
+        var d = devices[i];
+        Console.WriteLine($"  [{i}] {d.Name} ({d.Type}) — {d.Leds.Length} LEDs, {d.Zones.Length} zones");
+        Console.WriteLine($"       Active mode: {d.ActiveMode?.Name ?? "?"} (index {d.ActiveModeIndex})");
+
+        // Try setting Direct mode
+        try
+        {
+            for (int m = 0; m < d.Modes.Length; m++)
+            {
+                string modeName = d.Modes[m].Name ?? "";
+                Console.WriteLine($"       Mode [{m}]: {modeName}");
+            }
+
+            client.SetCustomMode(i);
+            Console.WriteLine($"       SetCustomMode() OK");
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"       SetCustomMode() failed: {ex.Message}");
+        }
+
+        // Try sending a colour
+        try
+        {
+            var colors = new OpenRGB.NET.Color[d.Leds.Length];
+            for (int k = 0; k < colors.Length; k++)
+                colors[k] = new OpenRGB.NET.Color(0, 100, 255); // Blue
+            client.UpdateLeds(i, colors);
+            Console.WriteLine($"       UpdateLeds() OK — set all LEDs to blue");
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"       UpdateLeds() failed: {ex.Message}");
+        }
+    }
+
+    client.Dispose();
+    Console.WriteLine("=== Test complete ===");
+}
+catch (Exception ex)
+{
+    Console.WriteLine($"FATAL: {ex.GetType().Name}: {ex.Message}");
+    Console.WriteLine(ex.StackTrace);
+}

test-openrgb.csx

@@ -0,0 +1,58 @@
+#!/usr/bin/env dotnet-script
+// Quick OpenRGB protocol test
+using System;
+using System.Net.Sockets;
+using System.Text;
+using System.Threading;
+
+var tcp = new TcpClient();
+tcp.Connect("127.0.0.1", 6742);
+Console.WriteLine("TCP connected OK");
+
+var stream = tcp.GetStream();
+stream.ReadTimeout = 3000;
+
+// Send OpenRGB protocol handshake: "OPEN" + uint32 protocol version
+var magic = Encoding.ASCII.GetBytes("OPEN");
+var version = BitConverter.GetBytes((uint)4);
+var handshake = new byte[magic.Length + version.Length];
+Buffer.BlockCopy(magic, 0, handshake, 0, magic.Length);
+Buffer.BlockCopy(version, 0, handshake, magic.Length, version.Length);
+stream.Write(handshake, 0, handshake.Length);
+Console.WriteLine($"Sent handshake: OPEN v4 ({handshake.Length} bytes)");
+
+Thread.Sleep(1000);
+
+// Read response
+var buf = new byte[256];
+try
+{
+    int read = stream.Read(buf, 0, 256);
+    Console.WriteLine($"Received {read} bytes");
+
+    // Check for "ORGB" magic in response
+    if (read >= 4)
+    {
+        string responseMagic = Encoding.ASCII.GetString(buf, 0, 4);
+        Console.WriteLine($"Response magic: '{responseMagic}'");
+
+        if (read >= 8)
+        {
+            uint serverVersion = BitConverter.ToUInt32(buf, 4);
+            Console.WriteLine($"Server protocol version: {serverVersion}");
+        }
+    }
+
+    // Print hex dump
+    Console.Write("Hex: ");
+    for (int i = 0; i < Math.Min(read, 32); i++)
+        Console.Write($"{buf[i]:X2} ");
+    Console.WriteLine();
+}
+catch (Exception ex)
+{
+    Console.WriteLine($"Read failed: {ex.Message}");
+}
+
+tcp.Close();
+Console.WriteLine("Done");