Align Host API access with interop MediaDevices/PeerConnection shims

CONTEXT.md

@@ -8,12 +8,14 @@ It contains **no implementation details** — only term definitions.
 ## Terms
 
 ### Host
-A peer that initiates a WebRTC session by opening a TCP listener and waiting for
-an incoming connection before creating an SDP offer.
+The API root object used as the non-browser equivalent of `Navigator`, including
+access to `MediaDevices`.
 
-### Guest
-A peer that joins a WebRTC session by dialling the Host's IP address and port,
-then responding to the Host's SDP offer with an SDP answer.
+### Caller
+A peer that initiates a WebRTC session by creating and sending the SDP offer.
+
+### Callee
+A peer that receives the SDP offer and responds with an SDP answer.
 
 ### Signaling
 The out-of-band exchange of SDP offers/answers and ICE candidates between two
@@ -32,3 +34,13 @@ a direct TCP signaling channel, targeting both .NET 10 and .NET Framework 4.8.
 A prototype `VideoRenderer` implementation backed by a WPF `WriteableBitmap`.
 Lives in `examples/BasicVideoChat` until a proper `WebRtcNet.Wpf` renderer
 assembly is created (see issue #36).
+
+## Relationships
+
+- **Host** exposes **MediaDevices** as the API entry point for capture access.
+- A **Caller** sends an SDP offer and a **Callee** returns an SDP answer.
+
+## Flagged ambiguities
+
+- "Host" previously meant the signaling initiator peer; resolved to the API root
+  object. Signaling roles are now **Caller** and **Callee**.

WebRtcInterop/Media/MediaDevices.cpp

@@ -0,0 +1,26 @@
+#include "pch.h"
+
+#include "MediaDevices.h"
+
+using namespace System::Collections::Generic;
+using namespace System::Threading::Tasks;
+
+namespace WebRtcInterop::Media
+{
+	Task<IEnumerable<WebRtcNet::Media::MediaDeviceInfo^>^>^ MediaDevices::EnumerateDevices()
+	{
+		auto devices = gcnew List<WebRtcNet::Media::MediaDeviceInfo^>();
+		return Task::FromResult<IEnumerable<WebRtcNet::Media::MediaDeviceInfo^>^>(devices);
+	}
+
+	WebRtcNet::Media::MediaTrackSupportedConstraints^ MediaDevices::GetSupportedConstraints()
+	{
+		return gcnew WebRtcNet::Media::MediaTrackSupportedConstraints();
+	}
+
+	Task<WebRtcNet::Media::MediaStream^>^ MediaDevices::GetUserMedia(WebRtcNet::Media::MediaStreamConstraints^ constraints)
+	{
+		return Task::FromException<WebRtcNet::Media::MediaStream^>(
+			gcnew WebRtcNet::Media::MediaStreamException("GetUserMedia is not currently implemented."));
+	}
+}

WebRtcInterop/Media/MediaDevices.h

@@ -0,0 +1,25 @@
+#pragma once
+
+namespace WebRtcInterop::Media
+{
+	using namespace System;
+	using namespace System::Collections::Generic;
+	using namespace System::Threading::Tasks;
+
+	public ref class MediaDevices : WebRtcNet::Media::MediaDevices
+	{
+	public:
+		virtual event EventHandler<WebRtcNet::Media::DeviceChangeEventArgs^>^ OnDeviceChange
+		{
+			void add(EventHandler<WebRtcNet::Media::DeviceChangeEventArgs^>^ value) override { on_device_change_ += value; }
+			void remove(EventHandler<WebRtcNet::Media::DeviceChangeEventArgs^>^ value) override { on_device_change_ -= value; }
+		}
+
+		virtual Task<IEnumerable<WebRtcNet::Media::MediaDeviceInfo^>^>^ EnumerateDevices() override;
+		virtual WebRtcNet::Media::MediaTrackSupportedConstraints^ GetSupportedConstraints() override;
+		virtual Task<WebRtcNet::Media::MediaStream^>^ GetUserMedia(WebRtcNet::Media::MediaStreamConstraints^ constraints) override;
+
+	private:
+		EventHandler<WebRtcNet::Media::DeviceChangeEventArgs^>^ on_device_change_;
+	};
+}

WebRtcInterop/Media/MediaDevicesFactory.cpp

@@ -0,0 +1,12 @@
+#include "pch.h"
+
+#include "MediaDevicesFactory.h"
+#include "MediaDevices.h"
+
+namespace WebRtcInterop::Media
+{
+	WebRtcNet::Media::MediaDevices^ MediaDevicesFactory::CreateMediaDevices()
+	{
+		return gcnew MediaDevices();
+	}
+}

WebRtcInterop/Media/MediaDevicesFactory.h

@@ -0,0 +1,10 @@
+#pragma once
+
+namespace WebRtcInterop::Media
+{
+	public ref class MediaDevicesFactory sealed
+	{
+	public:
+		static WebRtcNet::Media::MediaDevices^ CreateMediaDevices();
+	};
+}

WebRtcInterop/Media/MediaStream.cpp

@@ -12,23 +12,6 @@ using namespace WebRtcNet;
 
 namespace WebRtcInterop::Media
 {
-	Task<IEnumerable<MediaDeviceInfo^>^>^ MediaDevices::EnumerateDevices()
-	{
-		auto devices = gcnew List<MediaDeviceInfo^>();
-		return Task::FromResult<IEnumerable<MediaDeviceInfo^>^>(devices);
-	}
-
-	MediaTrackSupportedConstraints^ MediaDevices::GetSupportedConstraints()
-	{
-		return gcnew MediaTrackSupportedConstraints();
-	}
-
-	Task<WebRtcNet::Media::MediaStream^>^ MediaDevices::GetUserMedia(MediaStreamConstraints^ constraints)
-	{
-		return Task::FromException<WebRtcNet::Media::MediaStream^>(
-			gcnew MediaStreamException("GetUserMedia is not currently implemented."));
-	}
-
 	MediaStream::MediaStream(WebRtcNet::Media::MediaStream^ stream)
 		: _rpMediaStreamInterface(nullptr),
 		  on_active_(nullptr),

WebRtcInterop/Media/MediaStream.h

@@ -66,20 +66,4 @@ namespace WebRtcInterop::Media
 		EventHandler<WebRtcNet::Media::MediaStreamTrack^>^ on_remove_track_;
 	};
 
-	public ref class MediaDevices : WebRtcNet::Media::MediaDevices
-	{
-	public:
-		virtual event EventHandler<WebRtcNet::Media::DeviceChangeEventArgs^>^ OnDeviceChange
-		{
-			void add(EventHandler<WebRtcNet::Media::DeviceChangeEventArgs^>^ value) { on_device_change_ += value; }
-			void remove(EventHandler<WebRtcNet::Media::DeviceChangeEventArgs^>^ value) { on_device_change_ -= value; }
-		}
-
-		virtual Task<IEnumerable<WebRtcNet::Media::MediaDeviceInfo^>^>^ EnumerateDevices();
-		virtual WebRtcNet::Media::MediaTrackSupportedConstraints^ GetSupportedConstraints();
-		virtual Task<WebRtcNet::Media::MediaStream^>^ GetUserMedia(WebRtcNet::Media::MediaStreamConstraints^ constraints);
-
-	private:
-		EventHandler<WebRtcNet::Media::DeviceChangeEventArgs^>^ on_device_change_;
-	};
 }