Send service info on WebSocket connect

WirelessTextSyncer.Windows.Tests/SyncMessageTests.cs

@@ -74,6 +74,20 @@ public sealed class SyncMessageTests
         Assert.AreEqual(8181, root.GetProperty("port").GetInt32());
     }
 
+    [TestMethod]
+    public void WebSocketServiceInfoContainsDeviceName()
+    {
+        using var server = new WebSocketServerService(new SyncMessageHandler(new RecordingKeyboardInjectionService()), "Desktop-WIN11");
+
+        using var document = JsonDocument.Parse(server.BuildServiceInfoJson());
+        var root = document.RootElement;
+
+        Assert.AreEqual("wirelessTextSyncer.service", root.GetProperty("type").GetString());
+        Assert.AreEqual(1, root.GetProperty("version").GetInt32());
+        Assert.AreEqual("Desktop-WIN11", root.GetProperty("name").GetString());
+        Assert.AreEqual(8181, root.GetProperty("port").GetInt32());
+    }
+
     private sealed class RecordingKeyboardInjectionService : IKeyboardInjectionService
     {
         public List<string> Calls { get; } = [];

WirelessTextSyncer.Windows/Services/WebSocketServerService.cs

@@ -17,14 +17,16 @@ public sealed class WebSocketServerService : IDisposable
 
     private readonly TimeSpan heartbeatInterval = TimeSpan.FromSeconds(5);
     private readonly SyncMessageHandler messageHandler;
+    private readonly string deviceName;
     private readonly List<IWebSocketConnection> clients = [];
     private readonly object clientsLock = new();
     private WebSocketServer? server;
     private System.Threading.Timer? heartbeatTimer;
 
-    public WebSocketServerService(SyncMessageHandler messageHandler)
+    public WebSocketServerService(SyncMessageHandler messageHandler, string? deviceName = null)
     {
         this.messageHandler = messageHandler;
+        this.deviceName = string.IsNullOrWhiteSpace(deviceName) ? Environment.MachineName : deviceName;
     }
 
     public int Port { get; private set; } = 8181;
@@ -45,6 +47,18 @@ public sealed class WebSocketServerService : IDisposable
 
     public event EventHandler? StatusChanged;
 
+    public string BuildServiceInfoJson()
+    {
+        return JsonSerializer.Serialize(
+            new ServiceInfoMessage(
+                DiscoveryResponderService.ServiceResponseType,
+                1,
+                deviceName,
+                LocalIpAddress,
+                Port),
+            JsonOptions);
+    }
+
     public void Start(int port)
     {
         Port = port;
@@ -72,6 +86,7 @@ public sealed class WebSocketServerService : IDisposable
                 }
 
                 AppLogger.Info($"Client connected: {socket.ConnectionInfo.ClientIpAddress}:{socket.ConnectionInfo.ClientPort}");
+                _ = SendServiceInfoAsync(socket);
                 StatusChanged?.Invoke(this, EventArgs.Empty);
             };
             socket.OnClose = () =>
@@ -155,6 +170,19 @@ public sealed class WebSocketServerService : IDisposable
         }
     }
 
+    private async Task SendServiceInfoAsync(IWebSocketConnection client)
+    {
+        try
+        {
+            await client.Send(BuildServiceInfoJson());
+        }
+        catch (Exception exception)
+        {
+            AppLogger.Error("Failed to send WebSocket service info.", exception);
+            RemoveClient(client, "service info failure");
+        }
+    }
+
     private void RemoveClient(IWebSocketConnection client, string reason)
     {
         var removed = false;
@@ -215,4 +243,6 @@ public sealed class WebSocketServerService : IDisposable
 
         return address?.ToString() ?? "127.0.0.1";
     }
+
+    private sealed record ServiceInfoMessage(string Type, int Version, string Name, string Host, int Port);
 }