[Android MR] Migrate RemotingCastSession to CAF

This CL migrates RemotingCastSession into RemotingSessionController (CAF
version). Changes include:

* Abstract common logic from CastSessionController into BaseSessionController.
* Add onSessionStarted() and onSessionEnded() callback to BaseSessionController
  to handle session-specific logic regardless of session suspend.
* Return the correct namespaces in CastSessionController

Please diff BaseSessionController from Patchset 2 for easy review (other files
should be diff'ed against base)

Bug: 711860
Change-Id: I2bcb71b38758bb7f7b3a46f25cc4d55fe5c2956f
Reviewed-on: https://chromium-review.googlesource.com/1220300
Commit-Queue: Zhiqiang Zhang <zqzhang@chromium.org>
Reviewed-by: Thomas Guilbert <tguilbert@chromium.org>
Cr-Commit-Position: refs/heads/master@{#590566}

chrome/android/java/src/org/chromium/chrome/browser/media/router/caf/BaseSessionController.java

+// Copyright 2018 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.
+
+package org.chromium.chrome.browser.media.router.caf;
+
+import android.support.annotation.Nullable;
+import android.support.v7.media.MediaRouter;
+
+import com.google.android.gms.cast.CastDevice;
+import com.google.android.gms.cast.framework.CastSession;
+import com.google.android.gms.cast.framework.media.RemoteMediaClient;
+
+import org.chromium.base.Log;
+import org.chromium.chrome.browser.media.router.CastSessionUtil;
+import org.chromium.chrome.browser.media.router.FlingingController;
+import org.chromium.chrome.browser.media.router.MediaSink;
+import org.chromium.chrome.browser.media.router.MediaSource;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * A base wrapper for {@link CastSession}, extending its functionality for Chrome MediaRouter.
+ *
+ * Has persistent lifecycle and always attaches itself to the current {@link CastSession}.
+ */
+public class BaseSessionController {
+    private static final String TAG = "BaseSessionCtrl";
+
+    private CastSession mCastSession;
+    private final CafBaseMediaRouteProvider mProvider;
+    private final MediaRouter.Callback mMediaRouterCallbackForSessionLaunch;
+    private CreateRouteRequestInfo mRouteCreationInfo;
+    private final CafNotificationController mNotificationController;
+    private final RemoteMediaClient.Callback mRemoteMediaClientCallback;
+
+    public BaseSessionController(CafBaseMediaRouteProvider provider) {
+        mProvider = provider;
+        mMediaRouterCallbackForSessionLaunch = new MediaRouterCallbackForSessionLaunch();
+        mNotificationController = new CafNotificationController(this);
+        mRemoteMediaClientCallback = new RemoteMediaClientCallback();
+    }
+
+    public void requestSessionLaunch() {
+        mRouteCreationInfo = mProvider.getPendingCreateRouteRequestInfo();
+        CastUtils.getCastContext().setReceiverApplicationId(
+                mRouteCreationInfo.source.getApplicationId());
+
+        if (mRouteCreationInfo.routeInfo.isSelected()) {
+            // If a route has just been selected, CAF might not be ready yet before setting the app
+            // ID. So unselect and select the route will let CAF be aware that the route has been
+            // selected thus it can start the session.
+            //
+            // An issue of this workaround is that if a route is unselected and selected in a very
+            // short time, the selection might be ignored by MediaRouter, so put the reselection in
+            // a callback.
+            mProvider.getAndroidMediaRouter().addCallback(
+                    mRouteCreationInfo.source.buildRouteSelector(),
+                    mMediaRouterCallbackForSessionLaunch);
+            mProvider.getAndroidMediaRouter().unselect(MediaRouter.UNSELECT_REASON_UNKNOWN);
+        } else {
+            mRouteCreationInfo.routeInfo.select();
+        }
+    }
+
+    public MediaSource getSource() {
+        return (mRouteCreationInfo != null) ? mRouteCreationInfo.source : null;
+    }
+
+    public MediaSink getSink() {
+        return (mRouteCreationInfo != null) ? mRouteCreationInfo.sink : null;
+    }
+
+    public CreateRouteRequestInfo getRouteCreationInfo() {
+        return mRouteCreationInfo;
+    }
+
+    public CastSession getSession() {
+        return mCastSession;
+    }
+
+    public RemoteMediaClient getRemoteMediaClient() {
+        return mCastSession.getRemoteMediaClient();
+    }
+
+    public CafNotificationController getNotificationController() {
+        return mNotificationController;
+    }
+
+    public void endSession() {
+        MediaRouter mediaRouter = mProvider.getAndroidMediaRouter();
+        mediaRouter.selectRoute(mediaRouter.getDefaultRoute());
+    }
+
+    public List<String> getCapabilities() {
+        List<String> capabilities = new ArrayList<>();
+        if (mCastSession == null || !mCastSession.isConnected()) return capabilities;
+        CastDevice device = mCastSession.getCastDevice();
+        if (device.hasCapability(CastDevice.CAPABILITY_AUDIO_IN)) {
+            capabilities.add("audio_in");
+        }
+        if (device.hasCapability(CastDevice.CAPABILITY_AUDIO_OUT)) {
+            capabilities.add("audio_out");
+        }
+        if (device.hasCapability(CastDevice.CAPABILITY_VIDEO_IN)) {
+            capabilities.add("video_in");
+        }
+        if (device.hasCapability(CastDevice.CAPABILITY_VIDEO_OUT)) {
+            capabilities.add("video_out");
+        }
+        return capabilities;
+    }
+
+    public boolean isConnected() {
+        return mCastSession != null && mCastSession.isConnected();
+    }
+
+    private void updateRemoteMediaClient(String message) {
+        if (!isConnected()) return;
+
+        mCastSession.getRemoteMediaClient().onMessageReceived(
+                mCastSession.getCastDevice(), CastSessionUtil.MEDIA_NAMESPACE, message);
+    }
+
+    /** Attaches the controller to the current {@link CastSession}. */
+    public void attachToCastSession(CastSession session) {
+        mCastSession = session;
+        getRemoteMediaClient().registerCallback(mRemoteMediaClientCallback);
+    }
+
+    /** Detaches the controller from any {@link CastSession}. */
+    public void detachFromCastSession() {
+        if (mCastSession == null) return;
+
+        getRemoteMediaClient().unregisterCallback(mRemoteMediaClientCallback);
+        mCastSession = null;
+    }
+
+    /** Called when session started. */
+    public void onSessionStarted() {
+        mNotificationController.onSessionStarted();
+    }
+
+    /** Called when session ended. */
+    public void onSessionEnded() {
+        mNotificationController.onSessionEnded();
+        mRouteCreationInfo = null;
+    }
+
+    protected final CafBaseMediaRouteProvider getProvider() {
+        return mProvider;
+    }
+
+    /**
+     * All sub-classes need to register this method to listen to messages of the namespaces they are
+     * interested in.
+     */
+    protected void onMessageReceived(CastDevice castDevice, String namespace, String message) {
+        Log.d(TAG,
+                "Received message from Cast device: namespace=\"" + namespace + "\" message=\""
+                        + message + "\"");
+        if (CastSessionUtil.MEDIA_NAMESPACE.equals(namespace)) {
+            updateRemoteMediaClient(message);
+        }
+    }
+
+    private class MediaRouterCallbackForSessionLaunch extends MediaRouter.Callback {
+        @Override
+        public void onRouteUnselected(MediaRouter mediaRouter, MediaRouter.RouteInfo routeInfo) {
+            if (mProvider.getPendingCreateRouteRequestInfo() == null) return;
+
+            if (routeInfo.getId().equals(
+                        mProvider.getPendingCreateRouteRequestInfo().routeInfo.getId())) {
+                routeInfo.select();
+                mProvider.getAndroidMediaRouter().removeCallback(
+                        mMediaRouterCallbackForSessionLaunch);
+            }
+        }
+    }
+
+    private class RemoteMediaClientCallback extends RemoteMediaClient.Callback {
+        @Override
+        public void onStatusUpdated() {
+            mNotificationController.onStatusUpdated();
+        }
+
+        @Override
+        public void onMetadataUpdated() {
+            mNotificationController.onMetadataUpdated();
+        }
+    }
+
+    @Nullable
+    public FlingingController getFlingingController() {
+        return null;
+    }
+}

chrome/android/java/src/org/chromium/chrome/browser/media/router/caf/CafBaseMediaRouteProvider.java

@@ -217,7 +217,7 @@ public abstract class CafBaseMediaRouteProvider
     public void onSessionStarted(CastSession session, String sessionId) {
         Log.d(TAG, "onSessionStarted");
         mSessionController.attachToCastSession(session);
-        sessionController().getNotificationController().onSessionStarted();
+        sessionController().onSessionStarted();
 
         MediaSink sink = mPendingCreateRouteRequestInfo.sink;
         MediaSource source = mPendingCreateRouteRequestInfo.source;
@@ -269,7 +269,6 @@ public abstract class CafBaseMediaRouteProvider
             // sure the listener is not unregistered during a session relaunch.
             return;
         }
-        mSessionController.getNotificationController().onSessionEnded();
         mSessionController.detachFromCastSession();
         mSessionController.onSessionEnded();
         getAndroidMediaRouter().selectRoute(getAndroidMediaRouter().getDefaultRoute());

chrome/android/java/src/org/chromium/chrome/browser/media/router/caf/CafMessageHandler.java

@@ -494,8 +494,6 @@ public class CafMessageHandler {
      */
     @VisibleForTesting
     void onMediaMessage(String message, RequestRecord request) {
-        mSessionController.updateRemoteMediaClient(message);
-
         if (isMediaStatusMessage(message)) {
             // MEDIA_STATUS needs to be sent to all the clients.
             for (String clientId : mRouteProvider.getClientIdToRecords().keySet()) {

chrome/android/java/src/org/chromium/chrome/browser/media/router/caf/CafNotificationController.java

@@ -21,9 +21,9 @@ import org.chromium.content_public.common.MediaMetadata;
 /** Controller for updating media notification for Casting and MediaFling. */
 public class CafNotificationController implements MediaNotificationListener {
     private MediaNotificationInfo.Builder mNotificationBuilder;
-    private final CastSessionController mSessionController;
+    private final BaseSessionController mSessionController;
 
-    public CafNotificationController(CastSessionController sessionController) {
+    public CafNotificationController(BaseSessionController sessionController) {
         mSessionController = sessionController;
     }
 

chrome/android/java/src/org/chromium/chrome/browser/media/router/caf/remoting/FlingingControllerAdapter.java

+// Copyright 2018 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.
+
+package org.chromium.chrome.browser.media.router.caf.remoting;
+
+import com.google.android.gms.cast.framework.media.RemoteMediaClient;
+
+import org.chromium.chrome.browser.media.router.FlingingController;
+import org.chromium.chrome.browser.media.router.MediaController;
+import org.chromium.chrome.browser.media.router.MediaStatusObserver;
+
+/** Adapter class for bridging {@link RemoteMediaClient} and {@link FlingController}. */
+public class FlingingControllerAdapter implements FlingingController {
+    FlingingControllerAdapter(RemotingSessionController sessionController) {}
+
+    @Override
+    public MediaController getMediaController() {
+        // Not implemented.
+        return null;
+    }
+
+    @Override
+    public void setMediaStatusObserver(MediaStatusObserver observer) {
+        // Not implemented.
+    }
+
+    @Override
+    public void clearMediaStatusObserver() {
+        // Not implemented.
+    }
+
+    @Override
+    public long getApproximateCurrentTime() {
+        // Not implemented.
+        return 0;
+    }
+}

chrome/android/java/src/org/chromium/chrome/browser/media/router/caf/remoting/RemotingSessionController.java

+// Copyright 2018 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.
+
+package org.chromium.chrome.browser.media.router.caf.remoting;
+
+import com.google.android.gms.cast.MediaInfo;
+import com.google.android.gms.cast.framework.CastSession;
+
+import org.chromium.base.Log;
+import org.chromium.chrome.browser.media.router.CastSessionUtil;
+import org.chromium.chrome.browser.media.router.FlingingController;
+import org.chromium.chrome.browser.media.router.caf.BaseSessionController;
+import org.chromium.chrome.browser.media.router.caf.CafBaseMediaRouteProvider;
+import org.chromium.chrome.browser.media.router.cast.remoting.RemotingMediaSource;
+
+/** Wrapper for {@link CastSession} for remoting. */
+public class RemotingSessionController extends BaseSessionController {
+    private static final String TAG = "RmtSessionCtrl";
+
+    private FlingingControllerAdapter mFlingingControllerAdapter;
+    RemotingSessionController(CafBaseMediaRouteProvider provider) {
+        super(provider);
+        mFlingingControllerAdapter = new FlingingControllerAdapter(this);
+    }
+
+    @Override
+    public void attachToCastSession(CastSession session) {
+        super.attachToCastSession(session);
+
+        try {
+            getSession().setMessageReceivedCallbacks(
+                    CastSessionUtil.MEDIA_NAMESPACE, this ::onMessageReceived);
+        } catch (Exception e) {
+            Log.e(TAG, "Failed to register namespace listener for %s",
+                    CastSessionUtil.MEDIA_NAMESPACE, e);
+        }
+    }
+
+    @Override
+    public void onSessionStarted() {
+        getRemoteMediaClient().load(
+                new MediaInfo.Builder(((RemotingMediaSource) getSource()).getMediaUrl()).build());
+    }
+
+    @Override
+    public FlingingController getFlingingController() {
+        return mFlingingControllerAdapter;
+    }
+}

chrome/android/java/src/org/chromium/chrome/browser/media/router/cast/remoting/RemotingCastSession.java

@@ -35,6 +35,7 @@ import java.util.Set;
 /**
  * A wrapper around a RemoteMediaPlayer, used in remote playback.
  */
+// Migrated to RemotingSessionController. See https://crbug.com/711860.
 public class RemotingCastSession
         implements MediaNotificationListener, CastSession, Cast.MessageReceivedCallback {
     private static final String TAG = "MediaRouter";

chrome/android/java_sources.gni

@@ -792,6 +792,7 @@ chrome_java_sources = [
   "java/src/org/chromium/chrome/browser/media/router/MediaStatusBridge.java",
   "java/src/org/chromium/chrome/browser/media/router/MediaStatusObserver.java",
   "java/src/org/chromium/chrome/browser/media/router/MediaSink.java",
+  "java/src/org/chromium/chrome/browser/media/router/caf/BaseSessionController.java",
   "java/src/org/chromium/chrome/browser/media/router/caf/CastOptionsProvider.java",
   "java/src/org/chromium/chrome/browser/media/router/caf/CastSessionController.java",
   "java/src/org/chromium/chrome/browser/media/router/caf/CastUtils.java",
@@ -800,6 +801,8 @@ chrome_java_sources = [
   "java/src/org/chromium/chrome/browser/media/router/caf/CafMessageHandler.java",
   "java/src/org/chromium/chrome/browser/media/router/caf/CafNotificationController.java",
   "java/src/org/chromium/chrome/browser/media/router/caf/CreateRouteRequestInfo.java",
+  "java/src/org/chromium/chrome/browser/media/router/caf/remoting/RemotingSessionController.java",
+  "java/src/org/chromium/chrome/browser/media/router/caf/remoting/FlingingControllerAdapter.java",
   "java/src/org/chromium/chrome/browser/media/router/cast/BaseMediaRouteProvider.java",
   "java/src/org/chromium/chrome/browser/media/router/cast/CastMediaRouteProvider.java",
   "java/src/org/chromium/chrome/browser/media/router/cast/CastMediaSource.java",