[Media Router] Design MediaRouter interface with stub implementation.

chrome/browser/media/router/media_route_provider_manager_host.h

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_MEDIA_ROUTER_MEDIA_ROUTE_PROVIDER_MANAGER_HOST_H_
+#define CHROME_BROWSER_MEDIA_ROUTER_MEDIA_ROUTE_PROVIDER_MANAGER_HOST_H_
+
+#include <string>
+#include <vector>
+
+#include "base/callback.h"
+#include "chrome/browser/media/router/media_route.h"
+#include "chrome/browser/media/router/media_sink.h"
+#include "chrome/browser/media/router/media_source.h"
+
+namespace media_router {
+
+class MediaRoute;
+
+// Acts as the Chrome endpoint for communication between Media Router and
+// Media Route Providers (via the Media Route Provider Manager).
+class MediaRouteProviderManagerHost {
+ public:
+  virtual ~MediaRouteProviderManagerHost() {}
+
+  // Delegate called by the MediaRouteProviderManagerHost when a response is
+  // received from the MRPM.
+  class Delegate {
+   public:
+    virtual ~Delegate() {}
+
+    // Called when results from a media sinks query have been received.
+    // |source|: Media source of the query.
+    // |sinks|: List of sinks compatible with the source.
+    virtual void OnSinksReceived(const MediaSource& source,
+                                 const std::vector<MediaSink>& sinks) = 0;
+
+    // Called when there is a message from a route.
+    // |route_id|: The route ID.
+    // |message|: The message.
+    virtual void OnMessage(const MediaRouteId& route_id,
+                           const std::string& message) = 0;
+
+    // Called when a response to a route request has been received and
+    // a route has been established.
+    // |request_id|: ID of original request.
+    // |route|: Description of the established route.
+    virtual void OnRouteResponseReceived(const RouteRequestId& request_id,
+                                         const MediaRoute& route) = 0;
+
+    // Called when an error occurred while establishing a route.
+    // |request_id|: ID of original request.
+    // |error_text|: Text describing the error.
+    virtual void OnRouteResponseError(const RouteRequestId& request_id,
+                                      const std::string& error_text) = 0;
+
+    // Called when the list of currently MediaRoutes and their MediaSinks
+    // has been updated.
+    // |routes|: List of MediaRoutes.
+    // |sinks|: List of MediaSinks associated with the routes.
+    virtual void OnRoutesUpdated(
+        const std::vector<MediaRoute>& routes,
+        const std::vector<MediaSink>& sinks) = 0;
+
+    // Called when the MRPMHost is being destroyed.
+    virtual void OnHostDestroyed(MediaRouteProviderManagerHost* host) = 0;
+  };
+
+  // The following APIs allow the media router to send commands to the MRPM.
+
+  // Instructs MRPM to start a query for compatible media sinks for |source|.
+  // Results from the query and subsequent updates will be received via
+  // |Delegate::OnSinksReceived| until the query is removed from MRPM
+  // via |RemoveMediaSinksQuery|.
+  virtual void AddMediaSinksQuery(const MediaSource& source) = 0;
+
+  // Instructs MRPM to stop a query for compatible media sinks for |source|.
+  // The delegate will no longer receive updates.
+  virtual void RemoveMediaSinksQuery(const MediaSource& source) = 0;
+
+  // Requests MRPM to establish a route between |source| and a media sink given
+  // by |sink_id|. |request_id| is generated by Media Router and passed
+  // to MRPM to identify the request.
+  // Result of the request will be received via either |OnRouteResponseReceived|
+  // or |OnRouteResponseError|.
+  virtual void RequestRoute(const RouteRequestId& request_id,
+                            const MediaSource& source,
+                            const MediaSinkId& sink_id) = 0;
+
+  // Requests MRPM to close a route specified by |route_id|.
+  virtual void CloseRoute(const MediaRouteId& route_id) = 0;
+
+  // Requests MRPM to post |message| to a MediaSink connected by MediaRoute
+  // with |route_id|.
+  virtual void PostMessage(const MediaRouteId& route_id,
+                           const std::string& message) = 0;
+
+  // Requests MRPM to start a query for all MediaRoutes and their MediaSinks.
+  // The result and subsequent updates will be received via
+  // |Delegate::OnRoutesUpdated|.

[xhwang, 2015/04/06 20:51:31]

nit: You are not using "Delegate::" in other comments.

[imcheng, 2015/04/06 21:54:20]

Added Delegate:: to OnRouteResponse* comments above.

+  virtual void StartMediaRoutesQuery() = 0;
+
+  // Requests MRPM to stop the query. The delegate will no longer receive
+  // updates.
+  virtual void StopMediaRoutesQuery() = 0;
+};
+
+}  // namespace media_router
+
+#endif  // CHROME_BROWSER_MEDIA_ROUTER_MEDIA_ROUTE_PROVIDER_MANAGER_HOST_H_