Port managed client audio and Windows application

clients/windows/README.md

@@ -1,95 +1,43 @@
-# VoiceCat — Windows client
+# VoiceCat — Windows client
 
-WinForms (.NET 10 LTS) UI over `voicecat.dll` (MinGW-built `libvoicecat` shared library).
+The WinForms .NET 10 client uses `VoiceCat.Core` for TLS, TOFU, protocol state and encrypted UDP, and `VoiceCat.Audio` for streams, jitter, Opus and mixing. Its only native runtime component is `voicecat_media.dll`, the narrow Opus/RNNoise C shim. The old `voicecat.dll` core is no longer loaded or published.
 
-## Prerequisites
+## Build
 
-| Tool | Version | Notes |
-|------|---------|-------|
-| .NET SDK | 10.0.x | `dotnet --version` should report `10.0.*` |
-| CMake | 3.25+ | For building the C++ DLL |
-| MinGW-w64 / MSYS2 UCRT64 | GCC 13+ | `C:\tools\msys64\ucrt64` is the expected location |
-| vcpkg | any | `VCPKG_ROOT` env var must point to a bootstrapped clone |
-
-## Build order
-
-### 1. Build the server (for testing)
+Stage the pinned native media dependencies once, then build the solution:
 
 ```powershell
-cmake --preset dev
-cmake --build --preset dev --target voicecat-server
+./dotnet/build-native.ps1
+dotnet restore clients/windows/VoiceCat.slnx --locked-mode
+dotnet build clients/windows/VoiceCat.slnx -c Release --no-restore
 ```
 
-### 2. Build the DLL
+The original `VoiceCat.Interop` project remains in the repository as a migration oracle. The app references `VoiceCat.Managed`, whose compatibility facade lets the existing accessible WinForms UI keep its event-pump shape while all networking and audio state live in the idiomatic managed libraries.
+
+## Publish
 
 ```powershell
-cmake --preset windows-client
-cmake --build --preset windows-client
+./clients/windows/publish-client.ps1
 ```
 
-Output: `build/windows-client/bin/voicecat.dll`
+This produces a self-contained `win-x64` distribution in `dotnet/artifacts/client/win-x64`. The script requires `voicecat_media.dll` and fails if the legacy `voicecat.dll` appears.
 
-**Verify no MinGW runtime dependencies remain:**
-```powershell
-& "C:\tools\msys64\ucrt64\bin\objdump.exe" -p build/windows-client/bin/voicecat.dll |
-    Select-String "DLL Name"
-```
-Expected: only Windows system DLLs (`KERNEL32.dll`, `WS2_32.dll`, `BCRYPT.dll`, etc.).
-If `libgcc_s_seh-1.dll`, `libstdc++-6.dll`, or `libwinpthread-1.dll` appear, the
-`-static-libgcc -static-libstdc++ -static -lwinpthread` link flags in `core/CMakeLists.txt`
-are not taking effect — check the CMake log for the `VOICECAT_BUILD_SHARED+WIN32` branch.
-
-### 3. Build the C# solution
+The noninteractive startup and real WASAPI device check is:
 
 ```powershell
-cd clients/windows
-dotnet build VoiceCat.slnx
+./dotnet/artifacts/client/win-x64/VoiceCat.App.exe --smoke-test --audio
 ```
 
-The app's `Directory.Build.props` copies `voicecat.dll` from `../../build/windows-client/bin/`
-into the output directory automatically on every build.
+`--smoke-test` constructs the real main form and pumps the managed client. `--audio` additionally opens the default WASAPI capture and render endpoints, moves PCM through both for three seconds, and fails if capture produces no samples.
 
-## Running manually
+## Run manually
 
 ```powershell
-# Terminal 1 — start the server
-./build/dev/bin/voicecat-server.exe --name "My Server"
+# Terminal 1
+./dotnet/artifacts/server/win-x64/VoiceCat.Server.exe
 
-# Terminal 2 — launch the client
+# Terminal 2
 dotnet run --project clients/windows/VoiceCat.App/VoiceCat.App.csproj
 ```
 
-On first connect to a new server:
-- Enter `127.0.0.1` as the host (not `localhost` — Windows resolves `localhost` to `::1`
-  first, and while the server now dual-stacks, `127.0.0.1` is cleaner for local testing).
-- The server identity dialog will appear. The TLS leaf-cert SHA-256 fingerprint is shown;
-  accept to pin it. Subsequent connects to the same server will be silent (MATCHED).
-
-## M5 — Moderation & admin UI
-
-The WinForms client now exposes all M5 operations through the main menu and context menus:
-
-- **Admin → Server accounts…** — create, reset password, and delete server accounts
-  (requires `can_admin_accounts`).
-- **Channel tree right-click** — create, edit, and delete channels. The edit dialog exposes the
-  full per-channel Opus configuration: mono/stereo, sample rate, bitrate, frame size,
-  application mode, FEC, expected packet loss, DTX, and complexity.
-- **User list right-click** — move, kick, ban, server mute/deafen, and set permissions
-  (items are gated by your own permissions).
-- **Activity log** shows async `GenericResult` feedback for every moderation request.
-- **User list** shows text indicators for self-mute, self-deafen, server-mute, and
-  server-deafen states.
-
-These operations require an admin-provisioned account with the appropriate permissions; the
-connect dialog already supports username/password auth.
-
-## Known limitations
-
-- **PTT is focus-scoped** — the push-to-talk key only works while the VoiceCat window has
-  focus. A system-wide `WH_KEYBOARD_LL` hook is not used in v1 (permissions + AV risk).
-- **Receive-side noise reduction** checkbox in per-user tuning is wired end-to-end but is a
-  passthrough no-op until a real APM/NS backend is built (no working Windows/MSVC port of
-  `webrtc-audio-processing` upstream — see `docs/tech-stack.md §1`).
-- **TOFU pins the TLS leaf cert**, not the declared Ed25519 identity fingerprint. Both are
-  shown in the identity dialog, but the cert fingerprint is the value that is actually
-  verified on reconnect. See `docs/security.md §1.1`.
+Manual release validation still includes NVDA navigation and a ten-minute two-client listen test, as required by `docs/porting-to-dotnet.md`.

clients/windows/VoiceCat.App/Audio/InputDeviceCapture.cs

@@ -16,7 +16,7 @@ public sealed record InputDeviceInfo(string Id, string Name, bool IsDefault)
 /// the aux device is opened client-side and needs a WASAPI id, not a miniaudio one.</summary>
 public static class InputDeviceEnumerator
 {
-    public static IReadOnlyList<InputDeviceInfo> List()
+    public static IReadOnlyList<InputDeviceInfo> List(bool input = true)
     {
         var result = new List<InputDeviceInfo>();
         InputDeviceCapture.IMMDeviceEnumerator? enumerator = null;
@@ -29,7 +29,7 @@ public static class InputDeviceEnumerator
                 Type.GetTypeFromCLSID(new Guid("BCDE0395-E52F-467C-8E3D-C4579291692E"))!)!;
 
             // Resolve the default capture endpoint id so the picker can flag it.
-            if (enumerator.GetDefaultAudioEndpoint(1 /*eCapture*/, 0 /*eConsole*/,
+            if (enumerator.GetDefaultAudioEndpoint(input ? 1 : 0, 0 /*eConsole*/,
                     out var defDev) == 0 && defDev != null)
             {
                 try { if (defDev.GetId(out string id) == 0) defaultId = id; }
@@ -37,7 +37,7 @@ public static class InputDeviceEnumerator
             }
 
             // DEVICE_STATE_ACTIVE = 0x1 — only currently-usable endpoints.
-            if (enumerator.EnumAudioEndpoints(1 /*eCapture*/, 0x1, out collectionPtr) != 0
+            if (enumerator.EnumAudioEndpoints(input ? 1 : 0, 0x1, out collectionPtr) != 0
                 || collectionPtr == IntPtr.Zero)
                 return result;
 
@@ -107,6 +107,7 @@ public sealed class InputDeviceCapture : IDisposable
     private const int FrameSamples = 960;  // 20 ms
 
     private readonly string? _deviceId;  // null = system default capture endpoint
+    private readonly bool _loopback;
 
     private IAudioClient?        _audioClient;
     private IAudioCaptureClient? _captureClient;
@@ -123,8 +124,9 @@ public sealed class InputDeviceCapture : IDisposable
     // Init-done signal: Set() by the capture thread after activation completes.
     private readonly ManualResetEventSlim _initDone = new(false);
     private bool _initOk;
+    private int _disposed;
 
-    public InputDeviceCapture(string? deviceId) => _deviceId = deviceId;
+    public InputDeviceCapture(string? deviceId, bool loopback = false) { _deviceId = deviceId; _loopback = loopback; }
 
     /// <summary>Starts capture. Blocks until WASAPI activation completes (typically &lt;100 ms).
     /// Returns false if the device cannot be opened.</summary>
@@ -148,15 +150,13 @@ public sealed class InputDeviceCapture : IDisposable
     {
         _running = false;
         _bufferEvent?.Set();
-        _captureThread?.Join(500);
-        try { _audioClient?.Stop(); } catch { /* device already gone */ }
+        if (_captureThread is not null && !_captureThread.Join(5000)) throw new TimeoutException("Capture did not stop.");
     }
 
     public void Dispose()
     {
+        if (Interlocked.Exchange(ref _disposed, 1) != 0) return;
         Stop();
-        if (_captureClient != null) { Marshal.ReleaseComObject(_captureClient); _captureClient = null; }
-        if (_audioClient   != null) { Marshal.ReleaseComObject(_audioClient);   _audioClient   = null; }
         _bufferEvent?.Dispose();
         _initDone.Dispose();
     }
@@ -165,10 +165,19 @@ public sealed class InputDeviceCapture : IDisposable
 
     private void CaptureThreadProc()
     {
-        _initOk = ActivateAndStart();
-        _initDone.Set();
-        if (!_initOk) return;
-        CaptureLoop();
+        try
+        {
+            _initOk = ActivateAndStart();
+            _initDone.Set();
+            if (_initOk && _running) CaptureLoop();
+        }
+        catch { _initOk = false; _initDone.Set(); }
+        finally
+        {
+            try { _audioClient?.Stop(); } catch { }
+            if (_captureClient != null) { Marshal.ReleaseComObject(_captureClient); _captureClient = null; }
+            if (_audioClient != null) { Marshal.ReleaseComObject(_audioClient); _audioClient = null; }
+        }
     }
 
     private bool ActivateAndStart()
@@ -192,7 +201,7 @@ public sealed class InputDeviceCapture : IDisposable
                 Type.GetTypeFromCLSID(new Guid("BCDE0395-E52F-467C-8E3D-C4579291692E"))!)!;
 
             int hr = _deviceId is null
-                ? enumerator.GetDefaultAudioEndpoint(1 /*eCapture*/, 0 /*eConsole*/, out device)
+                ? enumerator.GetDefaultAudioEndpoint(_loopback ? 0 : 1, 0 /*eConsole*/, out device)
                 : enumerator.GetDevice(_deviceId, out device);
             if (hr != 0 || device == null) return false;
 
@@ -220,7 +229,7 @@ public sealed class InputDeviceCapture : IDisposable
         //   AUDCLNT_STREAMFLAGS_EVENTCALLBACK    = 0x00040000
         //   AUDCLNT_STREAMFLAGS_AUTOCONVERTPCM   = 0x80000000
         //   AUDCLNT_STREAMFLAGS_SRC_DEFAULT_QUALITY = 0x08000000
-        const uint streamFlags = 0x00040000u | 0x80000000u | 0x08000000u;
+        uint streamFlags = 0x00040000u | 0x80000000u | 0x08000000u | (_loopback ? 0x00020000u : 0u);
 
         foreach (int ch in new[] { 2, 1 })
         {
@@ -327,9 +336,7 @@ public sealed class InputDeviceCapture : IDisposable
 
     private void FlushFrame()
     {
-        var copy = new short[_accumBuf.Length];
-        _accumBuf.AsSpan().CopyTo(copy);
-        PcmFrameReady?.Invoke(copy, FrameSamples, _channels);
+        PcmFrameReady?.Invoke(_accumBuf, FrameSamples, _channels); // Borrowed until callback returns.
         _accumCount = 0;
     }
 

clients/windows/VoiceCat.App/Audio/ProcessAudioMixer.cs

@@ -1,148 +1,85 @@
+using VoiceCat.Audio;
 using VoiceCat.Interop;
 
-// Owns N ProcessLoopbackCapture instances, mixes their PCM every 20 ms, and feeds
-// the result to the core via vc_stream_feed_pcm. Used for per-app audio sharing.
 namespace VoiceCat.App.Audio;
 
+// Capture threads own their ring producers; the mix thread alone consumes them.
 public sealed class ProcessAudioMixer : IDisposable
 {
-    private const int SampleRate   = 48000;
-    private const int FrameSamples = 960;
-    private const int Channels     = 2; // stereo; captures fall back to mono if needed
-
-    private readonly List<ProcessLoopbackCapture> _captures = [];
-
-    // Per-capture latest frame, protected by _frameLock.
-    private readonly object _frameLock = new();
-    private List<short[]>   _latestFrames = [];
-    private int             _activeChannels = Channels;
-
-    private Thread?          _mixThread;
-    private volatile bool    _running;
-    private VoiceCatClient?  _client;
-    private uint             _streamId;
-
+    private sealed class Input
+    {
+        internal readonly PcmRing Ring = new(16384);
+        private readonly short[] stereo = new short[1920];
+        internal void Feed(short[] pcm, int channels)
+        {
+            if (channels == 2) { Ring.TryWrite(pcm); return; }
+            if (channels != 1 || pcm.Length > 960) return;
+            for (int i = 0; i < pcm.Length; i++) stereo[2 * i] = stereo[2 * i + 1] = pcm[i];
+            Ring.TryWrite(stereo.AsSpan(0, pcm.Length * 2));
+        }
+    }
+    private readonly List<ProcessLoopbackCapture> captures = [];
+    private Input[] inputs = [];
+    private Thread? thread;
+    private volatile bool running;
+    private VoiceCatClient? client;
+    private uint streamId;
     public void Start(AppAudioScope scope, VoiceCatClient client, uint streamId)
     {
-        if (_running) return;
-        _client   = client;
-        _streamId = streamId;
-
+        if (running) return;
+        this.client = client; this.streamId = streamId;
         var specs = ResolveCaptures(scope);
-        if (specs.Count == 0)
+        inputs = specs.Select(_ => new Input()).ToArray();
+        try
         {
-            // nothing to capture — scope resolved to empty set
-            return;
+            for (int i = 0; i < specs.Count; i++)
+            {
+                Input input = inputs[i]; var (pid, mode) = specs[i];
+                var capture = new ProcessLoopbackCapture(pid, mode);
+                capture.PcmFrameReady += (pcm, _, channels) => input.Feed(pcm, channels);
+                captures.Add(capture);
+                if (!capture.Start()) throw new InvalidOperationException("Process audio capture could not start.");
+            }
+            if (inputs.Length == 0) return;
+            running = true;
+            thread = new Thread(MixLoop) { IsBackground = true, Name = "ProcessAudioMixer" }; thread.Start();
         }
-
-        lock (_frameLock)
-        {
-            _latestFrames   = new List<short[]>(new short[specs.Count][]);
-            _activeChannels = Channels;
-        }
-
-        for (int i = 0; i < specs.Count; i++)
-        {
-            int captureIndex = i;
-            var (pid, mode) = specs[i];
-            var cap = new ProcessLoopbackCapture(pid, mode);
-            cap.PcmFrameReady += (pcm, spc, ch) => OnCaptureFrame(captureIndex, pcm, ch);
-            _captures.Add(cap);
-        }
-
-        foreach (var c in _captures) c.Start();
-
-        _running   = true;
-        _mixThread = new Thread(MixLoop) { IsBackground = true, Name = "ProcessAudioMixer" };
-        _mixThread.Start();
+        catch { Stop(); throw; }
     }
-
     public void Stop()
     {
-        _running = false;
-        _mixThread?.Join(500);
-        foreach (var c in _captures) { c.Stop(); c.Dispose(); }
-        _captures.Clear();
+        running = false;
+        if (thread is not null && !thread.Join(5000)) throw new TimeoutException("Process audio mixer did not stop.");
+        foreach (var capture in captures) capture.Dispose();
+        captures.Clear(); inputs = []; thread = null;
     }
-
     public void Dispose() => Stop();
-
-    // ── Capture callback ──────────────────────────────────────────────────────
-
-    private void OnCaptureFrame(int index, short[] pcm, int channels)
-    {
-        lock (_frameLock)
-        {
-            // Upmix mono → stereo interleave if the capture fell back to mono.
-            if (channels == 1 && _activeChannels == 2)
-                pcm = MonoToStereo(pcm);
-            if (index < _latestFrames.Count)
-                _latestFrames[index] = pcm;
-        }
-    }
-
-    // ── Mix loop (20 ms timer) ────────────────────────────────────────────────
-
     private void MixLoop()
     {
-        // Use a target period close to 20 ms; small under-shoot avoids accumulating drift.
-        const int periodMs = 19;
-        while (_running)
+        var frame = new short[1920]; var mix = new short[1920]; var sums = new int[1920];
+        long deadline = System.Diagnostics.Stopwatch.GetTimestamp();
+        while (running)
         {
-            Thread.Sleep(periodMs);
-            if (!_running) break;
-
-            short[] mix;
-            lock (_frameLock)
+            sums.AsSpan().Clear();
+            foreach (Input input in inputs)
             {
-                int len = FrameSamples * _activeChannels;
-                mix = new short[len];
-
-                foreach (var frame in _latestFrames)
-                {
-                    if (frame == null) continue;
-                    int frameLen = Math.Min(frame.Length, len);
-                    for (int i = 0; i < frameLen; i++)
-                    {
-                        int sum = mix[i] + frame[i];
-                        mix[i] = (short)Math.Clamp(sum, short.MinValue, short.MaxValue);
-                    }
-                }
+                while (input.Ring.Count > 11520) input.Ring.Read(frame);
+                frame.AsSpan().Clear(); input.Ring.Read(frame);
+                for (int i = 0; i < frame.Length; i++) sums[i] += frame[i];
             }
-
-            _client?.StreamFeedPcm(_streamId, mix, FrameSamples, (uint)_activeChannels);
+            for (int i = 0; i < mix.Length; i++) mix[i] = (short)Math.Clamp(sums[i], short.MinValue, short.MaxValue);
+            client?.StreamFeedPcm(streamId, mix, 960, 2);
+            deadline += System.Diagnostics.Stopwatch.Frequency / 50;
+            double wait = (deadline - System.Diagnostics.Stopwatch.GetTimestamp()) * 1000.0 / System.Diagnostics.Stopwatch.Frequency;
+            if (wait > 0) Thread.Sleep((int)Math.Ceiling(wait));
+            else if (wait < -100) deadline = System.Diagnostics.Stopwatch.GetTimestamp();
         }
     }
-
-    // ── Helpers ───────────────────────────────────────────────────────────────
-
-    // Resolve the scope to the WASAPI captures to open:
-    //  OnlyApps      → one INCLUDE capture per selected process tree.
-    //  AllExceptApps → one EXCLUDE capture of the single selected process tree, which
-    //                  natively captures the whole system render mix minus that tree
-    //                  (dynamic — apps launched later are included automatically).
-    private static List<(int pid, ProcessLoopbackCapture.Mode mode)> ResolveCaptures(AppAudioScope scope)
+    private static List<(int pid, ProcessLoopbackCapture.Mode mode)> ResolveCaptures(AppAudioScope scope) => scope switch
     {
-        return scope switch
-        {
-            OnlyApps      o => o.Pids.Select(p => (p, ProcessLoopbackCapture.Mode.Include)).ToList(),
-            AllExceptApps a when a.Pids.Count > 0 =>
-                [(a.Pids[0], ProcessLoopbackCapture.Mode.Exclude)],
-            // Entire desktop minus VoiceCat itself: EXCLUDE our own process tree.
-            EntireDesktop { ExcludeSelf: true } =>
-                [(Environment.ProcessId, ProcessLoopbackCapture.Mode.Exclude)],
-            _ => [],
-        };
-    }
-
-    private static short[] MonoToStereo(short[] mono)
-    {
-        var stereo = new short[mono.Length * 2];
-        for (int i = 0; i < mono.Length; i++)
-        {
-            stereo[i * 2]     = mono[i];
-            stereo[i * 2 + 1] = mono[i];
-        }
-        return stereo;
-    }
+        OnlyApps o => o.Pids.Select(p => (p, ProcessLoopbackCapture.Mode.Include)).ToList(),
+        AllExceptApps a when a.Pids.Count > 0 => [(a.Pids[0], ProcessLoopbackCapture.Mode.Exclude)],
+        EntireDesktop { ExcludeSelf: true } => [(Environment.ProcessId, ProcessLoopbackCapture.Mode.Exclude)],
+        _ => [],
+    };
 }

clients/windows/VoiceCat.App/Audio/ProcessLoopbackCapture.cs

@@ -64,15 +64,15 @@ public sealed class ProcessLoopbackCapture : IDisposable
     {
         _running = false;
         _bufferEvent?.Set();
-        _captureThread?.Join(500);
-        if (_audioClientPtr != IntPtr.Zero) AC_Stop(_audioClientPtr);
+        if (_captureThread is not null && !_captureThread.Join(5000))
+            throw new TimeoutException("Process capture did not stop.");
     }
 
+    private int _disposed;
     public void Dispose()
     {
+        if (Interlocked.Exchange(ref _disposed, 1) != 0) return;
         Stop();
-        ComRelease(ref _captureClientPtr);
-        ComRelease(ref _audioClientPtr);
         _bufferEvent?.Dispose();
         _initDone.Dispose();
     }
@@ -81,10 +81,23 @@ public sealed class ProcessLoopbackCapture : IDisposable
 
     private void CaptureThreadProc()
     {
-        _initOk = ActivateAndStart();
-        _initDone.Set();
-        if (!_initOk) return;
-        CaptureLoop();
+        try
+        {
+            _initOk = ActivateAndStart();
+            _initDone.Set();
+            if (_initOk && _running) CaptureLoop();
+        }
+        catch
+        {
+            _initOk = false;
+            _initDone.Set();
+        }
+        finally
+        {
+            if (_audioClientPtr != IntPtr.Zero) AC_Stop(_audioClientPtr);
+            ComRelease(ref _captureClientPtr);
+            ComRelease(ref _audioClientPtr);
+        }
     }
 
     private bool ActivateAndStart()
@@ -274,9 +287,9 @@ public sealed class ProcessLoopbackCapture : IDisposable
 
     private void FlushFrame()
     {
-        var copy = new short[_accumBuf.Length];
-        _accumBuf.AsSpan().CopyTo(copy);
-        PcmFrameReady?.Invoke(copy, FrameSamples, _channels);
+        // The callback borrows this buffer until it returns. This capture owner cannot
+        // overwrite it concurrently, which avoids one allocation every 20 ms.
+        PcmFrameReady?.Invoke(_accumBuf, FrameSamples, _channels);
         _accumCount = 0;
     }
 

clients/windows/VoiceCat.App/Audio/WasapiAudioBackend.cs

@@ -0,0 +1,113 @@
+using System.Runtime.InteropServices;
+using VoiceCat.Audio;
+using static VoiceCat.App.Audio.InputDeviceCapture;
+
+namespace VoiceCat.App.Audio;
+
+public sealed class WasapiAudioBackend : IAudioDeviceBackend
+{
+    public IReadOnlyList<AudioDeviceInfo> Enumerate(bool input) => InputDeviceEnumerator.List(input).Select(d => new AudioDeviceInfo(d.Id, d.Name, d.IsDefault)).ToArray();
+    public IAudioCapture OpenCapture(string? deviceId, bool loopback, CapturePcmHandler handler)
+    {
+        var capture = new InputDeviceCapture(NormalizeDeviceId(deviceId), loopback);
+        capture.PcmFrameReady += (pcm, _, channels) => handler(pcm, channels);
+        if (!capture.Start()) { capture.Dispose(); throw new InvalidOperationException("WASAPI capture could not start."); }
+        return new Capture(capture);
+    }
+    public IAudioPlayback OpenPlayback(string? deviceId = null) => new Playback(deviceId);
+    // The old miniaudio ABI persisted its raw device union as hex. Its Windows member
+    // is a null-terminated UTF-16 WASAPI endpoint id; preserve saved selections.
+    internal static string? NormalizeDeviceId(string? id)
+    {
+        if (string.IsNullOrEmpty(id)) return null;
+        if (id.StartsWith('{')) return id;
+        try
+        {
+            byte[] bytes = Convert.FromHexString(id);
+            string decoded = System.Text.Encoding.Unicode.GetString(bytes).Split('\0')[0];
+            return decoded.StartsWith('{') ? decoded : null;
+        }
+        catch (FormatException) { return id; }
+    }
+    private sealed class Capture(InputDeviceCapture capture) : IAudioCapture { public void Dispose() => capture.Dispose(); }
+
+    private sealed class Playback : IAudioPlayback
+    {
+        private readonly string? deviceId;
+        private readonly PcmRing pcm = new(32768);
+        private readonly ManualResetEventSlim initialized = new(false);
+        private readonly Thread thread;
+        private volatile bool running = true;
+        private bool ready;
+        private int disposed;
+        internal Playback(string? deviceId)
+        {
+            this.deviceId = deviceId;
+            thread = new Thread(Work) { IsBackground = true, Name = "VoiceCat WASAPI playback" };
+            thread.Start();
+            if (!initialized.Wait(5000) || !ready) { Dispose(); throw new InvalidOperationException("WASAPI playback could not start."); }
+        }
+        public void Write(ReadOnlySpan<short> stereoPcm) => pcm.TryWrite(stereoPcm);
+        private unsafe void Work()
+        {
+            IMMDeviceEnumerator? enumerator = null; IMMDevice? device = null; IAudioClient? client = null; IAudioRenderClient? render = null;
+            using var bufferReady = new AutoResetEvent(false);
+            try
+            {
+                enumerator = (IMMDeviceEnumerator)Activator.CreateInstance(Type.GetTypeFromCLSID(new Guid("BCDE0395-E52F-467C-8E3D-C4579291692E"))!)!;
+                int result = deviceId is null ? enumerator.GetDefaultAudioEndpoint(0, 0, out device) : enumerator.GetDevice(deviceId, out device);
+                if (result < 0 || device is null) return;
+                Guid iid = typeof(IAudioClient).GUID;
+                if (device.Activate(ref iid, 0x17, 0, out object audio) < 0) return;
+                client = (IAudioClient)audio;
+                WaveFormat format = new() { Format = 1, Channels = 2, Samples = 48000, Bytes = 192000, Align = 4, Bits = 16 };
+                if (client.Initialize(0, 0x00040000u | 0x80000000u | 0x08000000u, 600000, 0, (nint)(&format), 0) < 0) return;
+                if (client.GetBufferSize(out uint capacity) < 0 || client.SetEventHandle(bufferReady.SafeWaitHandle.DangerousGetHandle()) < 0) return;
+                iid = typeof(IAudioRenderClient).GUID;
+                if (client.GetService(ref iid, out object output) < 0) return;
+                render = (IAudioRenderClient)output;
+                if (client.Start() < 0) return;
+                ready = true; initialized.Set();
+                Span<short> discard = stackalloc short[1920];
+                while (running)
+                {
+                    bufferReady.WaitOne(20); // Scheduling wait is outside the buffer-fill cycle.
+                    if (!running || client.GetCurrentPadding(out uint padding) < 0) break;
+                    uint frames = capacity - Math.Min(capacity, padding);
+                    if (frames == 0) continue;
+                    if (render.GetBuffer(frames, out nint buffer) < 0) break;
+                    var destination = new Span<short>((void*)buffer, checked((int)frames * 2));
+                    // Keep queued playback bounded to ~120 ms, then fill underflow with silence.
+                    while (pcm.Count > 11520) pcm.Read(discard);
+                    int count = pcm.Read(destination); destination[count..].Clear();
+                    if (render.ReleaseBuffer(frames, 0) < 0) break;
+                }
+            }
+            catch { ready = false; }
+            finally
+            {
+                initialized.Set();
+                try { client?.Stop(); } catch { }
+                if (render is not null) Marshal.ReleaseComObject(render);
+                if (client is not null) Marshal.ReleaseComObject(client);
+                if (device is not null) Marshal.ReleaseComObject(device);
+                if (enumerator is not null) Marshal.ReleaseComObject(enumerator);
+            }
+        }
+        public void Dispose()
+        {
+            if (Interlocked.Exchange(ref disposed, 1) != 0) return;
+            running = false;
+            if (!thread.Join(5000)) throw new TimeoutException("WASAPI playback did not stop.");
+            initialized.Dispose();
+        }
+    }
+    [StructLayout(LayoutKind.Sequential, Pack = 2)]
+    private struct WaveFormat { internal ushort Format, Channels; internal uint Samples, Bytes; internal ushort Align, Bits, Extra; }
+    [ComImport, Guid("F294ACFC-3146-4483-A7BF-ADDCA7C260E2"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
+    private interface IAudioRenderClient
+    {
+        [PreserveSig] int GetBuffer(uint frames, out nint data);
+        [PreserveSig] int ReleaseBuffer(uint frames, uint flags);
+    }
+}

clients/windows/VoiceCat.App/Forms/ConnectDialog.cs

@@ -119,7 +119,7 @@ public partial class ConnectDialog : Form
         Directory.CreateDirectory(tofuDir);
 
         _client = new VoiceCatClient("VoiceCat-Windows", VoiceCatClient.VersionString,
-            VcLogLevel.Info, ServerListStore.TofuStorePath);
+            VcLogLevel.Info, ServerListStore.TofuStorePath, new VoiceCat.App.Audio.WasapiAudioBackend());
         _client.EventReceived += OnEvent;
         _identityDialogShown = false;
         _pumpTimer.Start();

clients/windows/VoiceCat.App/Program.cs

@@ -5,7 +5,7 @@ namespace VoiceCat.App;
 internal static class Program
 {
     [STAThread]
-    private static void Main()
+    private static int Main(string[] args)
     {
         // Surface exceptions that WinForms' default message-loop handling would otherwise
         // swallow silently (or crash with no visible cause).
@@ -16,12 +16,37 @@ internal static class Program
 
         ApplicationConfiguration.Initialize();
 
+        if (args.Contains("--smoke-test"))
+        {
+            try
+            {
+                using var client = new VoiceCat.Interop.VoiceCatClient("Smoke", "test");
+                using var form = new MainForm(client, 0, "Smoke", "Managed core");
+                form.CreateControl();
+                if (form.Controls.Count == 0 || string.IsNullOrEmpty(form.Text)) return 1;
+                client.PumpEvents();
+                if (args.Contains("--audio"))
+                {
+                    var backend = new Audio.WasapiAudioBackend();
+                    using var playback = backend.OpenPlayback();
+                    int samples = 0;
+                    using var capture = backend.OpenCapture(null, false, (pcm, _) => Interlocked.Add(ref samples, pcm.Length));
+                    short[] silence = new short[1920];
+                    for (int i = 0; i < 150; i++) { playback.Write(silence); Thread.Sleep(20); }
+                    if (samples == 0) return 2;
+                }
+                return 0;
+            }
+            catch { return 1; }
+        }
+
         using var connectDialog = new ConnectDialog();
         var result = connectDialog.ShowDialog();
         if (result != DialogResult.OK || connectDialog.ConnectedClient is null)
-            return;
+            return 0;
 
         Application.Run(new MainForm(connectDialog.ConnectedClient, connectDialog.SelfUserId,
             connectDialog.Nickname, connectDialog.ServerName));
+        return 0;
     }
 }

clients/windows/VoiceCat.App/VoiceCat.App.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <ItemGroup>
-    <ProjectReference Include="..\VoiceCat.Interop\VoiceCat.Interop.csproj" />
+    <ProjectReference Include="..\VoiceCat.Managed\VoiceCat.Managed.csproj" />
   </ItemGroup>
 
   <!-- Prismatoid — .NET bindings for the Prism speech library, used for spoken event
@@ -42,18 +42,6 @@
        as part of the Windows Desktop shared framework on net10.0-windows — no PackageReference
        needed (one was tried and NuGet flagged it as redundant/unprunable, NU1510). -->
 
-  <!-- voicecat.dll must exist (build the `windows-client` CMake preset first — see
-       clients/windows/README.md). -->
-  <ItemGroup>
-    <Content Include="$(VoiceCatNativeDir)\voicecat.dll" Condition="Exists('$(VoiceCatNativeDir)\voicecat.dll')">
-      <Link>voicecat.dll</Link>
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </Content>
-  </ItemGroup>
 
-  <Target Name="VoiceCatCheckNativeDll" BeforeTargets="Build">
-    <Error Condition="!Exists('$(VoiceCatNativeDir)\voicecat.dll')"
-           Text="voicecat.dll not found at '$(VoiceCatNativeDir)'. Build it first: cmake --preset windows-client &amp;&amp; cmake --build --preset windows-client (see clients/windows/README.md)." />
-  </Target>
 
-</Project>
+</Project>

clients/windows/VoiceCat.App/packages.publish.win-x64.lock.json

@@ -0,0 +1,77 @@
+{
+  "version": 1,
+  "dependencies": {
+    "net10.0-windows7.0": {
+      "Microsoft.NET.ILLink.Tasks": {
+        "type": "Direct",
+        "requested": "[10.0.7, )",
+        "resolved": "10.0.7",
+        "contentHash": "AA/yhzFHNtQZXLdqjzujPy25G8EWwGWsAnxOE2zYSBoT/8QHP6ketN3CToD3DFreO653ipUwnKHo22B8AlBMCw=="
+      },
+      "Prismatoid": {
+        "type": "Direct",
+        "requested": "[0.3.0, )",
+        "resolved": "0.3.0",
+        "contentHash": "mUOgtmFtjbLxydrdAImkfP3u0U8qrYkvfx2NlQqdQQ8TB9qe59BobxBCcNDo21g8xSefkBJB1VdGPbVTfiE7zw=="
+      },
+      "BouncyCastle.Cryptography": {
+        "type": "Transitive",
+        "resolved": "2.6.2",
+        "contentHash": "7oWOcvnntmMKNzDLsdxAYqApt+AjpRpP2CShjMfIa3umZ42UQMvH0tl1qAliYPNYO6vTdcGMqnRrCPmsfzTI1w=="
+      },
+      "Google.Protobuf": {
+        "type": "Transitive",
+        "resolved": "3.36.1",
+        "contentHash": "77AqPEoaY1ODE+syYBHti0jXiwQq0J/fUr/fRyYhNlc9oKtH5dZZEr/OLKtdKNVG83PRnCYB2r8B80ZrObzOGQ=="
+      },
+      "voicecat.audio": {
+        "type": "Project",
+        "dependencies": {
+          "VoiceCat.Codec": "[1.0.0, )",
+          "VoiceCat.Dsp": "[1.0.0, )",
+          "VoiceCat.Protocol": "[1.0.0, )"
+        }
+      },
+      "voicecat.codec": {
+        "type": "Project"
+      },
+      "voicecat.core": {
+        "type": "Project",
+        "dependencies": {
+          "VoiceCat.Audio": "[1.0.0, )",
+          "VoiceCat.Crypto": "[1.0.0, )"
+        }
+      },
+      "voicecat.crypto": {
+        "type": "Project",
+        "dependencies": {
+          "BouncyCastle.Cryptography": "[2.6.2, )",
+          "VoiceCat.Protocol": "[1.0.0, )"
+        }
+      },
+      "voicecat.dsp": {
+        "type": "Project"
+      },
+      "voicecat.managed": {
+        "type": "Project",
+        "dependencies": {
+          "VoiceCat.Core": "[1.0.0, )"
+        }
+      },
+      "voicecat.protocol": {
+        "type": "Project",
+        "dependencies": {
+          "Google.Protobuf": "[3.36.1, )"
+        }
+      }
+    },
+    "net10.0-windows7.0/win-x64": {
+      "Prismatoid": {
+        "type": "Direct",
+        "requested": "[0.3.0, )",
+        "resolved": "0.3.0",
+        "contentHash": "mUOgtmFtjbLxydrdAImkfP3u0U8qrYkvfx2NlQqdQQ8TB9qe59BobxBCcNDo21g8xSefkBJB1VdGPbVTfiE7zw=="
+      }
+    }
+  }
+}

clients/windows/VoiceCat.Interop.Tests/VoiceCatClientSmokeTests.cs

@@ -272,6 +272,8 @@ public sealed class VoiceCatClientSmokeTests : IDisposable
         Assert.Equal(VcResult.Ok, events.First(e => e.Type == VcEventType.AuthResult).Result);
         Assert.True(PumpUntil(client, () => events.Any(e => e.Type == VcEventType.ChannelList), 3000));
 
+        Assert.Equal(VcResult.Ok, client.JoinVoice());
+        Assert.True(PumpUntil(client, () => events.Any(e => e.Type == VcEventType.VoiceState && e.U32a == 1), 5000));
         // Give the async UDP binding handshake a moment to land before announcing a stream
         // (mirrors vccli's 500ms sleep after auth).
         Thread.Sleep(500);
@@ -340,6 +342,10 @@ public sealed class VoiceCatClientSmokeTests : IDisposable
         Assert.True(PumpUntil(b, () => eventsB.Any(e => e.Type == VcEventType.JoinResult), 5000),
             "B did not receive VC_EVENT_JOIN_RESULT");
 
+        Assert.Equal(VcResult.Ok, a.JoinVoice());
+        Assert.Equal(VcResult.Ok, b.JoinVoice());
+        Assert.True(PumpUntil(a, () => eventsA.Any(e => e.Type == VcEventType.VoiceState && e.U32a == 1), 5000));
+        Assert.True(PumpUntil(b, () => eventsB.Any(e => e.Type == VcEventType.VoiceState && e.U32a == 1), 5000));
         // UDP binding handshake is async; give it a moment (mirrors ScreenAudio test).
         Thread.Sleep(500);
 

clients/windows/VoiceCat.Interop/VoiceCat.Interop.csproj

@@ -9,5 +9,6 @@
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <RootNamespace>VoiceCat.Interop</RootNamespace>
   </PropertyGroup>
+  <ItemGroup><InternalsVisibleTo Include="VoiceCat.Interop.Tests" /></ItemGroup>
 
 </Project>

clients/windows/VoiceCat.Managed/Administration.cs

@@ -0,0 +1,32 @@
+using Voicecat.V1;
+
+namespace VoiceCat.Interop;
+
+public sealed partial class VoiceCatClient
+{
+    public VcResult KickUser(uint id, string? reason = null) => Request(new() { Kick = new() { UserId = id, Reason = reason ?? "" } });
+    public VcResult BanUser(uint id, string? reason = null, ulong expiresUnixMs = 0) => Request(new() { Ban = new() { UserId = id, Reason = reason ?? "", ExpiresUnixMs = expiresUnixMs } });
+    public VcResult MoveUser(uint id, uint channelId) => Request(new() { MoveUser = new() { UserId = id, ChannelId = channelId } });
+    public VcResult SetServerMute(uint id, bool muted, bool deafened) => Request(new() { ServerMute = new() { UserId = id, Muted = muted, Deafened = deafened } });
+    public VcResult SetPermission(uint id, PermissionsInfo permissions) => Request(new() { SetPermission = new() { UserId = id, Permissions = new()
+    { IsAdmin = permissions.IsAdmin, CanCreateTempChannel = permissions.CanCreateTempChannel, CanAdminAccounts = permissions.CanAdminAccounts, CanBan = permissions.CanBan, CanKick = permissions.CanKick, CanMoveUsers = permissions.CanMoveUsers } } });
+    public VcResult CreateAccount(string username, string password) => Request(new() { CreateAccount = new() { Username = username, Password = password } });
+    public VcResult ResetPassword(string username, string password) => Request(new() { ResetPassword = new() { Username = username, NewPassword = password } });
+    public VcResult DeleteAccount(string username) => Request(new() { DeleteAccount = new() { Username = username } });
+    public VcResult RequestAccountList() => Request(new() { ListAccounts = new() });
+    public VcResult CreateChannel(ChannelEditInfo info) => Request(new() { CreateChannel = new() { Channel = Channel(info), Password = info.Password ?? "" } });
+    public VcResult EditChannel(ChannelEditInfo info) => Request(new() { EditChannel = new() { Channel = Channel(info), Password = info.Password ?? "" } });
+    public VcResult DeleteChannel(uint id) => Request(new() { DeleteChannel = new() { ChannelId = id } });
+    public VcResult SendText(VcTextScope scope, uint targetId, string body)
+    {
+        try { core.Send(new() { TextMessage = new() { Scope = (TextScope)scope, TargetId = targetId, Body = body, ClientMsgId = Guid.NewGuid().ToString("N") } }); return VcResult.Ok; }
+        catch { return VcResult.NotConnected; }
+    }
+    private static Voicecat.V1.Channel Channel(ChannelEditInfo info) => new()
+    {
+        Id = info.Id, ParentId = info.ParentId, Name = info.Name, Topic = info.Topic, MaxUsers = info.MaxUsers, Order = unchecked((int)info.SortOrder),
+        Audio = new() { Codec = info.Audio.Codec, Mode = info.Audio.Stereo ? ChannelMode.ModeStereo : ChannelMode.ModeMono, SampleRate = info.Audio.SampleRate,
+            BitrateBps = info.Audio.BitrateBps, FrameMs = info.Audio.FrameMs, Application = (OpusApplication)info.Audio.Application, Complexity = info.Audio.Complexity,
+            Fec = info.Audio.Fec, ExpectedPacketLoss = info.Audio.ExpectedPacketLoss, Dtx = info.Audio.Dtx, Dred = info.Audio.Dred }
+    };
+}

clients/windows/VoiceCat.Managed/AudioControls.cs

@@ -0,0 +1,106 @@
+using VoiceCat.Audio;
+using Voicecat.V1;
+
+namespace VoiceCat.Interop;
+
+public sealed partial class VoiceCatClient
+{
+    private sealed record PcmRegistration(nint Callback, nint User);
+    private PcmRegistration? pcm;
+    public (VcResult Result, uint StreamId) StartStream(VcStreamKind kind, string label) => Start(kind, label, false);
+    public (VcResult Result, uint StreamId) StartStreamExternalFeed(VcStreamKind kind, string label) => Start(kind, label, true);
+    private (VcResult, uint) Start(VcStreamKind kind, string label, bool external)
+    {
+        StreamInfo? stream = null;
+        try
+        {
+            stream = core.StartStreamAsync((StreamKind)kind, label).GetAwaiter().GetResult();
+            local[stream.StreamId] = new(stream, external);
+            if (!external && backend is not null) captures[stream.StreamId] = Capture(stream);
+            return (VcResult.Ok, stream.StreamId);
+        }
+        catch (Exception exception)
+        {
+            if (stream is not null) { local.TryRemove(stream.StreamId, out _); core.StopStream(stream.StreamId); }
+            Queue(new(VcEventType.Error, Result: VcResult.Audio, Text: exception.Message)); return (VcResult.Audio, 0);
+        }
+    }
+    private IAudioCapture Capture(StreamInfo stream) => backend!.OpenCapture(devices.GetValueOrDefault(stream.StreamId), stream.Kind == StreamKind.StreamScreenAudio,
+        (samples, channels) => StreamFeedPcm(stream.StreamId, samples, samples.Length / channels, (uint)channels));
+    public VcResult StopStream(uint id)
+    {
+        if (captures.Remove(id, out var capture)) capture.Dispose();
+        if (!local.TryRemove(id, out LocalStream? stream)) return VcResult.InvalidArg;
+        try { core.StopStream(stream.Info.StreamId); return VcResult.Ok; } catch { return VcResult.NotConnected; }
+    }
+    public VcResult SetInputDevice(uint id, string? device)
+    {
+        devices[id] = device;
+        if (!captures.Remove(id, out var previous)) return VcResult.Ok;
+        previous.Dispose();
+        try { var info = local[id].Info.Clone(); info.StreamId = id; captures[id] = Capture(info); return VcResult.Ok; }
+        catch { return VcResult.Audio; }
+    }
+    public VcResult SetCaptureChannels(uint id, uint channels)
+    { try { LocalStream stream = local[id]; core.Audio.SetCaptureChannels(stream.Info.StreamId, checked((int)channels)); stream.CaptureChannels = (int)channels; return VcResult.Ok; } catch { return VcResult.InvalidArg; } }
+    public VcResult AudioRestart()
+    {
+        foreach (uint id in captures.Keys.ToArray()) { VcResult result = SetInputDevice(id, devices.GetValueOrDefault(id)); if (result != VcResult.Ok) return result; }
+        return VcResult.Ok;
+    }
+    public VcResult SetInputMode(VcInputMode mode) { if (!Enum.IsDefined(mode)) return VcResult.InvalidArg; core.Audio.InputMode = (AudioInputMode)mode; return VcResult.Ok; }
+    public VcResult SetVadThreshold(float threshold) { if (!float.IsFinite(threshold) || threshold is < 0 or > 1) return VcResult.InvalidArg; core.Audio.VadThreshold = threshold; return VcResult.Ok; }
+    public VcResult SetPushToTalk(bool active) { core.Audio.PushToTalk = active; return VcResult.Ok; }
+    public VcResult SetSelfMute(bool muted, bool deafened) { core.Audio.MicMuted = muted; core.Audio.Deafened = deafened; return VcResult.Ok; }
+    public VcResult SetOutputVolume(float gain) { if (!float.IsFinite(gain) || gain is < 0 or > 4) return VcResult.InvalidArg; core.Audio.OutputGain = gain; return VcResult.Ok; }
+    public VcResult SetInputGain(float gain) { if (!float.IsFinite(gain) || gain is < 0 or > 4) return VcResult.InvalidArg; core.Audio.InputGain = gain; return VcResult.Ok; }
+    public VcResult SetInputNoiseReduction(bool enabled) { core.Audio.InputNoiseReduction = enabled; return VcResult.Ok; }
+    public VcResult SetRemoteStream(uint userId, uint streamId, float gain, bool muted, bool nr)
+    { try { core.Audio.SetRemotePlayback(userId, streamId, gain, muted, nr); return VcResult.Ok; } catch { return VcResult.InvalidArg; } }
+    public (VcResult Result, RemoteStreamState? State) GetRemoteStream(uint userId, uint streamId)
+    {
+        var state = core.Audio.GetRemotePlayback(userId, streamId);
+        return state is { } value ? (VcResult.Ok, new(value.Gain, value.Muted, value.NoiseReduction)) : (VcResult.InvalidArg, null);
+    }
+    public (VcResult Result, AudioConfigInfo? Config) GetStreamAudioConfig(uint userId, uint streamId)
+    {
+        var info = core.Users.FirstOrDefault(u => u.Id == userId)?.Streams.FirstOrDefault(s => s.StreamId == streamId);
+        if (core.Authentication?.Self.Id == userId && local.TryGetValue(streamId, out LocalStream? own)) info = own.Info;
+        return info is null ? (VcResult.InvalidArg, null) : (VcResult.Ok, Audio(info.Audio));
+    }
+    public VcResult StreamFeedPcm(uint id, ReadOnlySpan<short> samples, int samplesPerChannel, uint channels)
+    {
+        if (samplesPerChannel < 0 || channels is not (1 or 2) || samples.Length != (long)samplesPerChannel * channels) return VcResult.InvalidArg;
+        if (!local.TryGetValue(id, out LocalStream? stream)) return VcResult.InvalidArg;
+        core.Audio.FeedPcm(Volatile.Read(ref stream.Info).StreamId, samples, (int)channels); return VcResult.Ok; // A full real-time ring drops, never waits.
+    }
+    public VcResult SetPcmSink(nint callback, nint user) { Volatile.Write(ref pcm, callback == 0 ? null : new(callback, user)); return VcResult.Ok; }
+    private unsafe void ForwardPcm(uint userId, uint streamId, ReadOnlySpan<short> samples, int channels)
+    {
+        var target = Volatile.Read(ref pcm); if (target is null) return;
+        fixed (short* input = samples)
+            ((delegate* unmanaged[Cdecl]<nint, uint, uint, short*, nuint, uint, uint, void>)target.Callback)(target.User, userId, streamId, input, (nuint)(samples.Length / channels), (uint)channels, 48000);
+    }
+
+    // Server-authoritative moves/edits stop old SSRCs. Reannounce with the new channel
+    // configuration while keeping UI/external-feed ids stable; captures continue feeding
+    // the alias and switch to the new audio owner only when negotiation completes.
+    private void ReconcileStreams()
+    {
+        var active = core.LocalStreams;
+        foreach (LocalStream stream in local.Values)
+            if (!active.Any(s => s.StreamId == stream.Info.StreamId) && Interlocked.CompareExchange(ref stream.Restarting, 1, 0) == 0) _ = RestartAsync(stream);
+    }
+    private async Task RestartAsync(LocalStream stream)
+    {
+        try
+        {
+            StreamInfo previous = stream.Info;
+            StreamInfo next = await core.StartStreamAsync(previous.Kind, previous.Label, stream.CaptureChannels).ConfigureAwait(false);
+            if (!local.ContainsKey(stream.Alias)) core.StopStream(next.StreamId);
+            else Volatile.Write(ref stream.Info, next);
+        }
+        catch (Exception exception) { Queue(new(VcEventType.Error, Result: VcResult.Audio, Text: exception.Message)); }
+        finally { Volatile.Write(ref stream.Restarting, 0); }
+    }
+}

clients/windows/VoiceCat.Managed/VoiceCat.Managed.csproj

@@ -0,0 +1,14 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
+    <RestorePackagesWithLockFile>true</RestorePackagesWithLockFile>
+  </PropertyGroup>
+  <ItemGroup>
+    <ProjectReference Include="../../../dotnet/src/VoiceCat.Core/VoiceCat.Core.csproj" />
+    <Compile Include="../VoiceCat.Interop/Enums.cs" Link="Enums.cs" />
+    <Compile Include="../VoiceCat.Interop/Models.cs" Link="Models.cs" />
+  </ItemGroup>
+</Project>

clients/windows/VoiceCat.Managed/VoiceCatClient.cs

@@ -0,0 +1,193 @@
+using System.Runtime.InteropServices;
+using System.Threading.Channels;
+using System.Collections.Concurrent;
+using VoiceCat.Audio;
+using VoiceCat.Core;
+using VoiceCat.Crypto;
+using Voicecat.V1;
+using CoreClient = VoiceCat.Core.VoiceCatClient;
+
+namespace VoiceCat.Interop;
+
+// Preserves the shipped WinForms call/event surface while its implementation moves to
+// the async managed core. Events still reach controls only through PumpEvents on the UI thread.
+public sealed partial class VoiceCatClient : IDisposable
+{
+    private readonly CoreClient core;
+    private readonly IAudioDeviceBackend? backend;
+    private readonly System.Threading.Channels.Channel<VoiceCatEvent> events = System.Threading.Channels.Channel.CreateUnbounded<VoiceCatEvent>();
+    private readonly Dictionary<uint, IAudioCapture> captures = [];
+    private readonly Dictionary<uint, string?> devices = [];
+    private readonly Dictionary<uint, StreamSummary[]> remoteStreams = [];
+    private readonly Dictionary<uint, bool> talkState = [];
+    private sealed class LocalStream(StreamInfo info, bool external)
+    {
+        internal readonly uint Alias = info.StreamId;
+        internal StreamInfo Info = info;
+        internal readonly bool External = external;
+        internal int CaptureChannels = 1;
+        internal int Restarting;
+    }
+    private readonly ConcurrentDictionary<uint, LocalStream> local = new();
+    private IAudioPlayback? playback;
+    private Task connecting = Task.CompletedTask;
+    private TaskCompletionSource<bool>? identity;
+    private int disposed;
+    private List<AccountInfo> accounts = [];
+    private bool audioFailureReported;
+    public event Action<VoiceCatEvent>? EventReceived;
+    public event Action<uint, float>? LevelChanged;
+    public CoreClient ManagedClient => core;
+
+    public VoiceCatClient(string clientName, string clientVersion, VcLogLevel logLevel = VcLogLevel.Info, string? tofuStorePath = null, IAudioDeviceBackend? audioBackend = null)
+    {
+        backend = audioBackend;
+        core = new(clientName, clientVersion, tofuStorePath);
+        core.ConnectionStateChanged += state =>
+        {
+            VcConnectionState mapped = state switch { ClientConnectionState.Connecting => VcConnectionState.Connecting, ClientConnectionState.VerifyingIdentity => VcConnectionState.VerifyingIdentity,
+                ClientConnectionState.Authenticating => VcConnectionState.Authenticating, ClientConnectionState.Connected => VcConnectionState.Connected, _ => VcConnectionState.Disconnected };
+            Queue(new(VcEventType.ConnectionState, ConnectionState: mapped));
+            if (mapped == VcConnectionState.Disconnected) Queue(new(VcEventType.Disconnected));
+        };
+        core.Audio.MixedPcm += pcm => Volatile.Read(ref playback)?.Write(pcm);
+        core.Audio.StreamPcm += ForwardPcm;
+    }
+
+    private void Queue(VoiceCatEvent message) => events.Writer.TryWrite(message);
+    public VcResult Connect(string host, ushort port)
+    {
+        if (!connecting.IsCompleted || core.State != ClientConnectionState.Disconnected) return VcResult.Already;
+        connecting = ConnectAsync(host, port);
+        return VcResult.Ok;
+    }
+    private async Task ConnectAsync(string host, ushort port)
+    {
+        try
+        {
+            await core.ConnectAsync(host, port, async (challenge, token) =>
+            {
+                identity = new(TaskCreationOptions.RunContinuationsAsynchronously);
+                Queue(new(VcEventType.ServerIdentity, U32a: (uint)challenge.Status, Text: challenge.CertificateFingerprint));
+                return await identity.Task.WaitAsync(token).ConfigureAwait(false);
+            }).ConfigureAwait(false);
+        }
+        catch (Exception exception) { Queue(new(VcEventType.Error, Result: VcResult.Io, Text: exception.Message)); }
+    }
+    public VcResult ConfirmServerIdentity(bool accept) { identity?.TrySetResult(accept); return VcResult.Ok; }
+    public VcResult AuthenticateGuest(string nickname) { _ = AuthenticateAsync(() => core.AuthenticateGuestAsync(nickname)); return VcResult.Ok; }
+    public VcResult AuthenticateUser(string username, string password) { _ = AuthenticateAsync(() => core.AuthenticateUserAsync(username, password)); return VcResult.Ok; }
+    private async Task AuthenticateAsync(Func<Task<AuthResult>> authenticate)
+    {
+        try { await connecting.ConfigureAwait(false); await authenticate().ConfigureAwait(false); }
+        catch (Exception exception) { Queue(new(VcEventType.AuthResult, Result: VcResult.AuthFailed, Text: exception.Message)); }
+    }
+    public VcResult Disconnect()
+    {
+        StopDevices(); core.DisconnectAsync().GetAwaiter().GetResult(); return VcResult.Ok;
+    }
+    public string GetServerIdentityDisplay() => core.ServerHello is { } hello ? Convert.ToHexString(hello.ServerIdentityFingerprint.Span) : "";
+
+    public void PumpEvents()
+    {
+        if (!audioFailureReported && core.Audio.Failure is { } failure) { audioFailureReported = true; Queue(new(VcEventType.Error, Result: VcResult.Audio, Text: failure.Message)); }
+        while (core.TryReadEvent(out Envelope? message)) Translate(message!);
+        while (events.Reader.TryRead(out VoiceCatEvent? message)) EventReceived?.Invoke(message);
+        foreach (LocalStream stream in local.Values)
+        {
+            var info = Volatile.Read(ref stream.Info);
+            var level = core.Audio.GetLocalLevel(info.StreamId); LevelChanged?.Invoke(stream.Alias, level.Level);
+            if (talkState.GetValueOrDefault(stream.Alias) != level.Talking)
+            {
+                talkState[stream.Alias] = level.Talking;
+                if (core.State == ClientConnectionState.Connected) core.Send(new() { StreamState = new() { StreamId = info.StreamId, Talking = level.Talking, Muted = core.Audio.MicMuted } });
+                EventReceived?.Invoke(new(VcEventType.TalkState, UserId: core.Authentication?.Self.Id ?? 0, StreamId: stream.Alias, U32a: level.Talking ? 1U : 0));
+            }
+        }
+    }
+
+    private void Translate(Envelope message)
+    {
+        if (message.AuthResult is not null) Queue(new(VcEventType.AuthResult, Result: message.AuthResult.Ok ? VcResult.Ok : VcResult.AuthFailed, UserId: message.AuthResult.Self?.Id ?? 0, Text: message.AuthResult.Error));
+        if (message.ServerState is not null) { remoteStreams.Clear(); foreach (User user in message.ServerState.Users) UpdateStreams(user); Queue(new(VcEventType.ChannelList)); }
+        if (message.ChannelEvent is not null) Queue(new(VcEventType.ChannelList));
+        if (message.UserEvent is not null)
+        {
+            var change = message.UserEvent;
+            if (change.User is { VoiceSubscribed: true } self && self.Id == core.Authentication?.Self.Id) ReconcileStreams();
+            if (change.User is not null) UpdateStreams(change.User);
+            if (change.Kind == UserEvent.Types.Kind.Left) remoteStreams.Remove(change.LeftId);
+            Queue(new(change.Kind switch { UserEvent.Types.Kind.Joined => VcEventType.UserJoined, UserEvent.Types.Kind.Left => VcEventType.UserLeft, _ => VcEventType.UserUpdated }, UserId: change.User?.Id ?? change.LeftId,
+                ChannelId: change.User?.ChannelId ?? 0, Text: change.Kind == UserEvent.Types.Kind.Joined ? change.User?.Nickname : change.Reason));
+        }
+        if (message.JoinChannelResult is not null) Queue(new(VcEventType.JoinResult, Result: message.JoinChannelResult.Ok ? VcResult.Ok : VcResult.InvalidArg, ChannelId: message.JoinChannelResult.ChannelId, Text: message.JoinChannelResult.Error));
+        if (message.VoiceSubscriptionResult is not null) Queue(new(VcEventType.VoiceState, U32a: message.VoiceSubscriptionResult.Subscribed ? 1U : 0));
+        if (message.TextMessage is not null) Queue(new(VcEventType.TextMessage, UserId: message.TextMessage.SenderId, ChannelId: message.TextMessage.TargetId, TextScope: (VcTextScope)message.TextMessage.Scope, Text: message.TextMessage.Body, TimestampUnixMs: message.TextMessage.SentAtUnixMs));
+        if (message.StreamState is not null) Queue(new(VcEventType.TalkState, UserId: message.StreamState.UserId, StreamId: message.StreamState.UserId == core.Authentication?.Self.Id ? local.Values.FirstOrDefault(s => s.Info.StreamId == message.StreamState.StreamId)?.Alias ?? message.StreamState.StreamId : message.StreamState.StreamId, U32a: message.StreamState.Talking ? 1U : 0));
+        if (message.GenericResult is not null) Queue(new(VcEventType.GenericResult, Result: message.GenericResult.Ok ? VcResult.Ok : message.GenericResult.Code == 6 ? VcResult.PermissionDenied : VcResult.InvalidArg, U32a: message.GenericResult.Code, Text: message.GenericResult.Message));
+        if (message.ListAccountsResult is not null)
+        {
+            accounts = message.ListAccountsResult.Accounts.Select(a => new AccountInfo(a.Username, a.IsAdmin, a.CreatedAtUnixMs, a.LastLoginUnixMs)).ToList();
+            Queue(new(VcEventType.AccountList));
+        }
+        if (message.Disconnect is not null) Queue(new(VcEventType.Error, Result: VcResult.Io, Text: message.Disconnect.Reason));
+    }
+
+    private void UpdateStreams(User user)
+    {
+        StreamSummary[] previous = remoteStreams.GetValueOrDefault(user.Id, []);
+        StreamSummary[] next = user.Id == core.Authentication?.Self.Id ? ListUserStreams(user.Id).ToArray() : user.Streams.Select(s => new StreamSummary(s.StreamId, (VcStreamKind)s.Kind, s.Label)).ToArray();
+        foreach (var stream in previous) if (!next.Any(s => s.StreamId == stream.StreamId)) Queue(new(VcEventType.StreamStopped, UserId: user.Id, StreamId: stream.StreamId));
+        foreach (var stream in next) if (!previous.Any(s => s.StreamId == stream.StreamId)) Queue(new(VcEventType.StreamStarted, UserId: user.Id, StreamId: stream.StreamId, U32a: (uint)stream.Kind, Text: stream.Label));
+        remoteStreams[user.Id] = next;
+    }
+
+    private VcResult Request(Envelope request)
+    {
+        if (core.State != ClientConnectionState.Connected) return VcResult.NotConnected;
+        try { _ = RequestAsync(request); return VcResult.Ok; }
+        catch { return VcResult.NotConnected; }
+    }
+    private async Task RequestAsync(Envelope request)
+    {
+        try { await core.RequestAsync(request).ConfigureAwait(false); }
+        catch (Exception exception) { Queue(new(VcEventType.Error, Result: VcResult.Io, Text: exception.Message)); }
+    }
+    public VcResult JoinChannel(uint id, string? password = null) => Request(new() { JoinChannel = new() { ChannelId = id, Password = password ?? "" } });
+    public VcResult LeaveChannel() => Request(new() { LeaveChannel = new() });
+    public VcResult JoinVoice()
+    {
+        try
+        {
+            if (backend is not null && playback is null) playback = backend.OpenPlayback();
+            var result = core.SubscribeVoiceAsync().GetAwaiter().GetResult();
+            if (!result.Ok) { Interlocked.Exchange(ref playback, null)?.Dispose(); }
+            return result.Ok ? VcResult.Ok : VcResult.Audio;
+        }
+        catch (Exception exception) { Queue(new(VcEventType.Error, Result: VcResult.Audio, Text: exception.Message)); return VcResult.Audio; }
+    }
+    public VcResult LeaveVoice() { StopDevices(); local.Clear(); return Request(new() { UnsubscribeVoice = new() }); }
+
+    public List<ChannelInfo> ListChannels() => core.Channels.Select(c => new ChannelInfo(c.Id, c.ParentId, c.Name, c.Topic, c.PasswordProtected, c.MaxUsers, unchecked((uint)c.Order), Audio(c.Audio))).ToList();
+    public List<UserInfo> ListUsers() => core.Users.Select(u => new UserInfo(u.Id, u.Nickname, u.IsGuest, u.ChannelId, u.SelfMicMuted, u.SelfDeafened, u.ServerMuted, u.ServerDeafened, u.VoiceSubscribed)).ToList();
+    public List<StreamSummary> ListUserStreams(uint id) => id == core.Authentication?.Self.Id
+        ? local.Values.Select(s => new StreamSummary(s.Alias, (VcStreamKind)s.Info.Kind, s.Info.Label)).ToList()
+        : core.Users.FirstOrDefault(u => u.Id == id)?.Streams.Select(s => new StreamSummary(s.StreamId, (VcStreamKind)s.Kind, s.Label)).ToList() ?? [];
+    public PermissionsInfo GetPermissions() { Permissions p = core.Authentication?.Permissions ?? new(); return new(p.CanCreateTempChannel, p.CanKick, p.CanBan, p.CanMoveUsers, p.CanAdminAccounts, p.IsAdmin); }
+    public List<AccountInfo> ListAccounts() => accounts.ToList();
+    public List<DeviceInfo> ListDevices(VcDeviceKind kind) => backend?.Enumerate(kind == VcDeviceKind.Input).Select(d => new DeviceInfo(d.Id, d.Name, d.IsDefault)).ToList() ?? [];
+    public static string VersionString => "VoiceCat managed core 0.1.0 (protocol v2)";
+    public static string ResultString(VcResult result) => result.ToString();
+    private static AudioConfigInfo Audio(AudioConfig a) => new(a.Codec, a.Mode == ChannelMode.ModeStereo, a.SampleRate, a.BitrateBps, a.FrameMs, (uint)a.Application, a.Fec, a.ExpectedPacketLoss, a.Dtx, a.Complexity, a.Dred);
+
+    private void StopDevices()
+    {
+        foreach (var capture in captures.Values) capture.Dispose(); captures.Clear(); local.Clear();
+        IAudioPlayback? previous = Interlocked.Exchange(ref playback, null); previous?.Dispose();
+    }
+    public void Dispose()
+    {
+        if (Interlocked.Exchange(ref disposed, 1) != 0) return;
+        identity?.TrySetResult(false); StopDevices(); core.DisposeAsync().AsTask().GetAwaiter().GetResult();
+    }
+}

clients/windows/VoiceCat.Managed/VoiceCatEvent.cs

@@ -0,0 +1,7 @@
+namespace VoiceCat.Interop;
+
+// Compatibility event consumed by WinForms. The managed core owns protocol and audio;
+// this assembly contains no libvoicecat bindings or native handles.
+public sealed record VoiceCatEvent(VcEventType Type, VcConnectionState ConnectionState = VcConnectionState.Disconnected,
+    VcResult Result = VcResult.Ok, uint UserId = 0, uint ChannelId = 0, uint StreamId = 0, VcTextScope TextScope = VcTextScope.Channel,
+    uint U32a = 0, string? Text = null, ulong TimestampUnixMs = 0);

clients/windows/VoiceCat.Managed/packages.lock.json

@@ -0,0 +1,51 @@
+{
+  "version": 1,
+  "dependencies": {
+    "net10.0": {
+      "BouncyCastle.Cryptography": {
+        "type": "Transitive",
+        "resolved": "2.6.2",
+        "contentHash": "7oWOcvnntmMKNzDLsdxAYqApt+AjpRpP2CShjMfIa3umZ42UQMvH0tl1qAliYPNYO6vTdcGMqnRrCPmsfzTI1w=="
+      },
+      "Google.Protobuf": {
+        "type": "Transitive",
+        "resolved": "3.36.1",
+        "contentHash": "77AqPEoaY1ODE+syYBHti0jXiwQq0J/fUr/fRyYhNlc9oKtH5dZZEr/OLKtdKNVG83PRnCYB2r8B80ZrObzOGQ=="
+      },
+      "voicecat.audio": {
+        "type": "Project",
+        "dependencies": {
+          "VoiceCat.Codec": "[1.0.0, )",
+          "VoiceCat.Dsp": "[1.0.0, )",
+          "VoiceCat.Protocol": "[1.0.0, )"
+        }
+      },
+      "voicecat.codec": {
+        "type": "Project"
+      },
+      "voicecat.core": {
+        "type": "Project",
+        "dependencies": {
+          "VoiceCat.Audio": "[1.0.0, )",
+          "VoiceCat.Crypto": "[1.0.0, )"
+        }
+      },
+      "voicecat.crypto": {
+        "type": "Project",
+        "dependencies": {
+          "BouncyCastle.Cryptography": "[2.6.2, )",
+          "VoiceCat.Protocol": "[1.0.0, )"
+        }
+      },
+      "voicecat.dsp": {
+        "type": "Project"
+      },
+      "voicecat.protocol": {
+        "type": "Project",
+        "dependencies": {
+          "Google.Protobuf": "[3.36.1, )"
+        }
+      }
+    }
+  }
+}

clients/windows/VoiceCat.Managed/packages.publish.win-x64.lock.json

@@ -0,0 +1,58 @@
+{
+  "version": 1,
+  "dependencies": {
+    "net10.0": {
+      "Microsoft.NET.ILLink.Tasks": {
+        "type": "Direct",
+        "requested": "[10.0.7, )",
+        "resolved": "10.0.7",
+        "contentHash": "AA/yhzFHNtQZXLdqjzujPy25G8EWwGWsAnxOE2zYSBoT/8QHP6ketN3CToD3DFreO653ipUwnKHo22B8AlBMCw=="
+      },
+      "BouncyCastle.Cryptography": {
+        "type": "Transitive",
+        "resolved": "2.6.2",
+        "contentHash": "7oWOcvnntmMKNzDLsdxAYqApt+AjpRpP2CShjMfIa3umZ42UQMvH0tl1qAliYPNYO6vTdcGMqnRrCPmsfzTI1w=="
+      },
+      "Google.Protobuf": {
+        "type": "Transitive",
+        "resolved": "3.36.1",
+        "contentHash": "77AqPEoaY1ODE+syYBHti0jXiwQq0J/fUr/fRyYhNlc9oKtH5dZZEr/OLKtdKNVG83PRnCYB2r8B80ZrObzOGQ=="
+      },
+      "voicecat.audio": {
+        "type": "Project",
+        "dependencies": {
+          "VoiceCat.Codec": "[1.0.0, )",
+          "VoiceCat.Dsp": "[1.0.0, )",
+          "VoiceCat.Protocol": "[1.0.0, )"
+        }
+      },
+      "voicecat.codec": {
+        "type": "Project"
+      },
+      "voicecat.core": {
+        "type": "Project",
+        "dependencies": {
+          "VoiceCat.Audio": "[1.0.0, )",
+          "VoiceCat.Crypto": "[1.0.0, )"
+        }
+      },
+      "voicecat.crypto": {
+        "type": "Project",
+        "dependencies": {
+          "BouncyCastle.Cryptography": "[2.6.2, )",
+          "VoiceCat.Protocol": "[1.0.0, )"
+        }
+      },
+      "voicecat.dsp": {
+        "type": "Project"
+      },
+      "voicecat.protocol": {
+        "type": "Project",
+        "dependencies": {
+          "Google.Protobuf": "[3.36.1, )"
+        }
+      }
+    },
+    "net10.0/win-x64": {}
+  }
+}

clients/windows/VoiceCat.slnx

@@ -1,5 +1,14 @@
 <Solution>
+  <Folder Name="/Managed core/">
+    <Project Path="../../dotnet/src/VoiceCat.Core/VoiceCat.Core.csproj" />
+    <Project Path="../../dotnet/src/VoiceCat.Audio/VoiceCat.Audio.csproj" />
+    <Project Path="../../dotnet/src/VoiceCat.Codec/VoiceCat.Codec.csproj" />
+    <Project Path="../../dotnet/src/VoiceCat.Crypto/VoiceCat.Crypto.csproj" />
+    <Project Path="../../dotnet/src/VoiceCat.Dsp/VoiceCat.Dsp.csproj" />
+    <Project Path="../../dotnet/src/VoiceCat.Protocol/VoiceCat.Protocol.csproj" />
+  </Folder>
   <Project Path="VoiceCat.App/VoiceCat.App.csproj" />
   <Project Path="VoiceCat.Interop.Tests/VoiceCat.Interop.Tests.csproj" />
   <Project Path="VoiceCat.Interop/VoiceCat.Interop.csproj" />
+  <Project Path="VoiceCat.Managed/VoiceCat.Managed.csproj" />
 </Solution>

clients/windows/publish-client.ps1

@@ -0,0 +1,15 @@
+param(
+    [string]$RuntimeIdentifier = "win-x64",
+    [string]$Output = ""
+)
+$ErrorActionPreference = "Stop"
+$repoRoot = (Resolve-Path "$PSScriptRoot/../..").Path
+if ([string]::IsNullOrWhiteSpace($Output)) { $Output = "$repoRoot/dotnet/artifacts/client/$RuntimeIdentifier" }
+dotnet publish "$PSScriptRoot/VoiceCat.App/VoiceCat.App.csproj" -c Release -r $RuntimeIdentifier --self-contained true `
+    -p:PublishSingleFile=true -p:PublishTrimmed=false -p:IncludeNativeLibrariesForSelfExtract=false `
+    -p:RestorePackagesWithLockFile=true -p:RestoreLockedMode=true `
+    "-p:NuGetLockFilePath=packages.publish.$RuntimeIdentifier.lock.json" -o $Output
+if ($LASTEXITCODE -ne 0) { throw "Managed Windows client publish failed." }
+if (-not (Test-Path "$Output/voicecat_media.dll")) { throw "Managed media shim was not published." }
+if (Test-Path "$Output/voicecat.dll") { throw "Legacy VoiceCat native core must not be published." }
+Write-Host "Published managed Windows client to $Output"