Centralize Dings playback and volume

tests/AquaSynth.Dsl.Tests/AquaSynth.Dsl.Tests.csproj

@@ -16,6 +16,7 @@
 
   <ItemGroup>
     <ProjectReference Include="..\..\tools\AquaSynthDingsMcp\AquaSynthDingsMcp.csproj" />
+    <ProjectReference Include="..\..\src\AquaSynth.Dings\AquaSynth.Dings.csproj" />
     <Using Include="Xunit" />
     <Using Include="AquaSynth.Faust" />
   </ItemGroup>

tests/AquaSynth.Dsl.Tests/DingCatalogTests.cs

@@ -1,4 +1,4 @@
-using AquaSynthDingsMcp;
+using AquaSynth.Dings;
 
 namespace AquaSynth.Dsl.Tests;
 

tests/AquaSynth.Dsl.Tests/DingsBridgeTests.cs

@@ -0,0 +1,66 @@
+using AquaSynth.Dings;
+using AquaSynthDingsMcp;
+
+namespace AquaSynth.Dsl.Tests;
+
+public sealed class DingsBridgeTests
+{
+    [Fact]
+    public async Task SeparateBridgesObserveOneHostVolumeAuthority()
+    {
+        var host = new FakeHostClient();
+        var first = new DingService(host);
+        var second = new DingService(host);
+
+        await first.SetVolumeAsync(.27f, CancellationToken.None);
+        var observed = await second.GetVolumeAsync(CancellationToken.None);
+
+        Assert.Equal(.27f, observed.Volume);
+        Assert.All(host.Commands, command => Assert.Equal(DingsProtocol.Version, command.Version));
+    }
+
+    [Fact]
+    public async Task PerPlayGainDoesNotMutateMasterVolume()
+    {
+        var host = new FakeHostClient { Volume = .4f };
+        var service = new DingService(host);
+
+        await service.PlayAsync("task.complete", "warm-bell", .7f, CancellationToken.None);
+
+        Assert.Equal(.4f, host.Volume);
+        Assert.Equal(.7f, host.Commands.Single().Value);
+    }
+
+    [Fact]
+    public void BridgeProjectContainsNoAudioOutputOwner()
+    {
+        var root = RepositoryRoot();
+        var bridge = Path.Combine(root, "tools", "AquaSynthDingsMcp");
+        var source = string.Join('\n', Directory.EnumerateFiles(bridge, "*.cs").Select(File.ReadAllText));
+        Assert.DoesNotContain("WaveOutEvent", source, StringComparison.Ordinal);
+        Assert.DoesNotContain("WasapiOut", source, StringComparison.Ordinal);
+        Assert.DoesNotContain("MixingSampleProvider", source, StringComparison.Ordinal);
+    }
+
+    private static string RepositoryRoot()
+    {
+        for (var dir = new DirectoryInfo(AppContext.BaseDirectory); dir is not null; dir = dir.Parent)
+            if (File.Exists(Path.Combine(dir.FullName, "AquaSynth.sln"))) return dir.FullName;
+        throw new InvalidOperationException("Repository root not found.");
+    }
+
+    private sealed class FakeHostClient : IDingsHostClient
+    {
+        public List<DingsCommand> Commands { get; } = [];
+        public float Volume { get; set; } = 1;
+        public bool Muted { get; set; }
+
+        public Task<DingsResponse> SendAsync(DingsCommand command, CancellationToken cancellationToken)
+        {
+            Commands.Add(command);
+            if (command.Kind == DingsCommandKind.SetVolume) Volume = command.Value;
+            if (command.Kind == DingsCommandKind.SetMuted) Muted = command.Value >= .5f;
+            return Task.FromResult(new DingsResponse(DingsProtocol.Version, true, "ok", Volume: Volume, Muted: Muted, HostProcessId: 42));
+        }
+    }
+}