Media Remoting: Draw remoting interstitial on poster image.

media/remoting/remoting_renderer_controller.h

 // Copyright 2016 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 MEDIA_REMOTING_REMOTING_RENDERER_CONTROLLER_H_
 #define MEDIA_REMOTING_REMOTING_RENDERER_CONTROLLER_H_
 
 #include "base/callback.h"
 #include "base/memory/weak_ptr.h"
 #include "media/base/media_observer.h"
 #include "media/remoting/remoting_source_impl.h"
+#include "third_party/skia/include/core/SkBitmap.h"
 
 namespace media {
 
 namespace remoting {
 class RpcBroker;
 }
 
 // This class:
 // 1) Implements the RemotingSourceImpl::Client;
 // 2) Monitors player events as a MediaObserver;
 // 3) May trigger the switch of the media renderer between local playback
 // and remoting.
 class RemotingRendererController final : public RemotingSourceImpl::Client,
                                          public MediaObserver {
  public:
   explicit RemotingRendererController(
       scoped_refptr<RemotingSourceImpl> remoting_source);
   ~RemotingRendererController() override;
 
   // RemotingSourceImpl::Client implemenations.
   void OnStarted(bool success) override;
   void OnSessionStateChanged() override;
 
   // MediaObserver implementations.
   void OnEnteredFullscreen() override;
   void OnExitedFullscreen() override;
   void OnSetCdm(CdmContext* cdm_context) override;
   void OnMetadataChanged(const PipelineMetadata& metadata) override;
+  void OnSetPoster(const GURL& poster) override;
 
   void SetSwitchRendererCallback(const base::Closure& cb);
 
+  using DownloadPosterCallback =
+      base::Callback<void(const GURL&,
+                          const base::Callback<void(const SkBitmap&)>&)>;
+  // Set the callback to download poster image. Can only be called once.
+  void SetDownloadPosterCallback(const DownloadPosterCallback& cb);
+
   base::WeakPtr<RemotingRendererController> GetWeakPtr() {
     return weak_factory_.GetWeakPtr();
   }
 
   // Used by RemotingRendererFactory to query whether to create Media Remoting
   // Renderer.
   bool remote_rendering_started() const {
     DCHECK(thread_checker_.CalledOnValidThread());
     return remote_rendering_started_;
   }
@@ skipping 30 matching lines @@
   bool IsVideoCodecSupported();
   bool IsAudioCodecSupported();
 
   // Helper to decide whether to enter or leave Remoting mode.
   bool ShouldBeRemoting();
 
   // Determines whether to enter or leave Remoting mode and switches if
   // necessary.
   void UpdateAndMaybeSwitch();
 
-  // Indicates whether this media element or its ancestor is in full screen.
+  // Called to download the poster image. Called when:
+  // 1. Poster URL changes.
+  // 2. ShowInterstitialCallback is set.
+  // 3. DownloadPosterCallback is set.
+  void DownloadPosterImage();
+
+  // Called when poster image is downloaded.
+  void OnPosterImageDownloaded(const GURL& download_url, const SkBitmap& image);
+
+  // Update remoting interstitial with |image|. When |image| is empty,
+  // interstitial will be drawn on previously downloaded poster image (in
+  // RemoteRendererImpl) or black background if none was downloaded before.
+  // TODO(xjz): https://codereview.chromium.org/2566223005/
+  // Call this when:
+  // 1. SetShowInterstitialCallback() is called (RemoteRendererImpl is created).
+  // 2. The remoting session is shut down (to update the status message in the
+  //    interstitial).
+  // 3. The size of the canvas is changed (to update the background image and
+  //    the position of the status message).
+  // 4. Poster image is downloaded (to update the background image).
+  void UpdateInterstitial(const SkBitmap& image);
+
+  // Indicates whether this media element is in full screen.
   bool is_fullscreen_ = false;
 
   // Indicates whether remoting is started.
   bool remote_rendering_started_ = false;
 
   // Indicates whether audio or video is encrypted.
   bool is_encrypted_ = false;
 
   // Current audio/video config.
   VideoDecoderConfig video_decoder_config_;
   AudioDecoderConfig audio_decoder_config_;
 
   // The callback to switch the media renderer.
   base::Closure switch_renderer_cb_;
 
   // This is initially the RemotingSourceImpl passed to the ctor, and might be
   // replaced with a different instance later if OnSetCdm() is called.
   scoped_refptr<RemotingSourceImpl> remoting_source_;
 
   // This is used to check all the methods are called on the current thread in
   // debug builds.
   base::ThreadChecker thread_checker_;
 
+  // Current pipeline metadata.
   PipelineMetadata pipeline_metadata_;
 
+  // Current poster URL, whose image will feed into the local UI.
+  GURL poster_url_;
+
+  // The callback to download the poster image. Called when |poster_url_|
+  // changes during a remoting session or the show interstial callback is set.
+  // OnPosterImageDownloaded() will be called when download completes.
+  DownloadPosterCallback download_poster_cb_;
+
   base::WeakPtrFactory<RemotingRendererController> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RemotingRendererController);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_REMOTING_REMOTING_RENDERER_CONTROLLER_H_