Use System.CommandLine for entry point parsing

packages/experimental/cua-windows/native/entry/CuaWindows.csproj

@@ -12,8 +12,13 @@
     <ApplicationManifest>app.manifest</ApplicationManifest>
     <DebugType>none</DebugType>
     <DebugSymbols>false</DebugSymbols>
+	<RootNamespace>DeepSeek.Cua.Windows</RootNamespace>
   </PropertyGroup>
 
+  <ItemGroup>
+    <PackageReference Include="System.CommandLine" Version="2.0.14" />
+  </ItemGroup>
+
   <ItemGroup>
     <ProjectReference Include="../protocol/CuaProtocol.csproj" />
   </ItemGroup>

packages/experimental/cua-windows/native/entry/Program.cs

@@ -1,35 +1,59 @@
 // The executable is a private helper launched by the dsh Windows provider.
+using System.CommandLine;
 using DeepSeek.Cua.Protocol;
+using DeepSeek.Cua.Windows;
 
-namespace DeepSeek.Cua.Windows;
-
-internal static class Program
+try
 {
-    private static int Main(string[] args)
+#if NETFRAMEWORK
+    if (Environment.OSVersion.Version.Build < 19041)
     {
-        try
-        {
-            if (!OperatingSystem.IsWindowsVersionAtLeast(10, 0, 19041)) throw new NativeFailure("UNSUPPORTED", "Windows CUA requires Windows 10 build 19041 or later");
-            var server = args.Length == 7 && args[0] == "--shared-server";
-            var bridge = args.Length == 7 && args[0] == "--bridge";
-            var connector = args.Length == 9 && args[0] == "--serve" && args[1] == "--instance-id" && Guid.TryParseExact(args[2], "N", out _);
-            var offset = server || bridge ? 1 : 3;
-            if ((!server && !connector && !bridge) || args[offset] != "--runtime-key" || args[offset + 2] != "--connect-timeout-ms"
-                || args[offset + 4] != "--grace-ms"
-                || !int.TryParse(args[offset + 3], out var connectTimeoutMs) || connectTimeoutMs <= 0
-                || !int.TryParse(args[offset + 5], out var graceMs) || graceMs <= 0)
-                throw new NativeFailure("INVALID_ARGUMENT", "The helper must be launched by the dsh Windows provider");
-            var runtime = Applications.Digest(Environment.ProcessPath!);
-            if (runtime != args[offset + 1]) throw new NativeFailure("NATIVE_STARTUP", "The helper executable changed before startup");
-            if (server) SharedRuntime.Serve(runtime, connectTimeoutMs, graceMs);
-            else if (bridge) SharedRuntime.Bridge(runtime, connectTimeoutMs).GetAwaiter().GetResult();
-            else SharedRuntime.Connect(args[2], runtime, connectTimeoutMs, graceMs).GetAwaiter().GetResult();
-            return 0;
-        }
-        catch (Exception error)
-        {
-            Console.Error.WriteLine(error is NativeFailure failure ? $"{failure.Code}: {failure.Message}" : $"NATIVE_STARTUP: {error.Message}");
-            return 1;
-        }
+        throw new NativeFailure("UNSUPPORTED", "Windows CUA requires Windows 10 build 19041 or later");
     }
+#endif
+
+    var serve = new Option<bool>("--serve") { Arity = ArgumentArity.Zero };
+    var sharedServer = new Option<bool>("--shared-server") { Arity = ArgumentArity.Zero };
+    var bridge = new Option<bool>("--bridge") { Arity = ArgumentArity.Zero };
+    var instanceId = new Option<Guid>("--instance-id");
+    var runtimeKey = new Option<string>("--runtime-key") { Required = true };
+    var connectTimeoutMs = new Option<int>("--connect-timeout-ms") { Required = true };
+    var graceMs = new Option<int>("--grace-ms") ;
+
+    var rootCommand = new RootCommand
+    {
+        Options =
+        {
+            serve,
+            sharedServer,
+            bridge,
+            instanceId,
+            runtimeKey,
+            connectTimeoutMs,
+            graceMs,
+        }
+    };
+
+    var parseResult = rootCommand.Parse(args);
+    if (parseResult.Errors.Count != 0)
+        throw new NativeFailure("INVALID_ARGUMENT", "The helper must be launched by the dsh Windows provider");
+
+    var runtime = Applications.Digest(Environment.ProcessPath!);
+    if (runtime != parseResult.GetValue(runtimeKey)) throw new NativeFailure("NATIVE_STARTUP", "The helper executable changed before startup");
+
+    if (parseResult.GetValue(sharedServer))
+        SharedRuntime.Serve(runtime, parseResult.GetRequiredValue(connectTimeoutMs), parseResult.GetRequiredValue(graceMs));
+    else if (parseResult.GetValue(bridge))
+        await SharedRuntime.Bridge(runtime, parseResult.GetRequiredValue(connectTimeoutMs));
+    else if (parseResult.GetValue(serve))
+        await SharedRuntime.Connect(parseResult.GetRequiredValue(instanceId).ToString("N"), runtime, parseResult.GetRequiredValue(connectTimeoutMs), parseResult.GetRequiredValue(graceMs));
+    else
+        throw new NativeFailure("INVALID_ARGUMENT", "The helper must be launched by the dsh Windows provider");
+
+    return 0;
+}
+catch (Exception error)
+{
+    Console.Error.WriteLine(error is NativeFailure failure ? $"{failure.Code}: {failure.Message}" : $"NATIVE_STARTUP: {error.Message}");
+    return -1;
 }

packages/experimental/cua-windows/native/entry/packages.lock.json

@@ -17,6 +17,15 @@
         "resolved": "1.15.0",
         "contentHash": "FbU0El+EEjdpuIX4iDbeS7ki1uzpJPx8vbqOzEtqnl1GZeAGJfq+jCbxeJL2y0EPnUNk8dRnnqR2xnYXg9Tf+g=="
       },
+      "System.CommandLine": {
+        "type": "Direct",
+        "requested": "[2.0.14, )",
+        "resolved": "2.0.14",
+        "contentHash": "15fyVO4aG6poR6IKmhM74zf7PUzaU6FZAGm2d3SQSO9yIyGAeo44e6t9qeKjjaqyMEqYdqcb2G1B0gpLoDU2cA==",
+        "dependencies": {
+          "System.Memory": "4.5.5"
+        }
+      },
       "System.Text.Json": {
         "type": "Direct",
         "requested": "[10.0.14, 10.0.14]",