[Media controls] Integrate rotate-to-fullscreen with orientation lock

third_party/WebKit/Source/modules/media_controls/MediaControlsOrientationLockDelegate.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 MediaControlsOrientationLockDelegate_h
 #define MediaControlsOrientationLockDelegate_h
 
 #include "core/events/EventListener.h"
+#include "device/screen_orientation/public/interfaces/screen_orientation.mojom-blink.h"
 #include "modules/ModulesExport.h"
 #include "public/platform/modules/screen_orientation/WebScreenOrientationLockType.h"
 
 namespace blink {
 
+class DeviceOrientationEvent;
 class Document;
 class HTMLVideoElement;
 
 // MediaControlsOrientationLockDelegate is implementing the orientation lock
 // feature when a <video> is fullscreen. It is meant to be created by
 // `MediaControlsImpl` when the feature applies. Once created, it will use
 // events to change state.
 //
+// The behavior depends on whether MediaControlsRotateToFullscreenDelegate is
+// enabled. If it is enabled and the user has not locked the screen orientation
+// at the OS level, then the orientation lock is only held until the user
+// rotates their device to match the orientation of the video; otherwise it is
+// held until fullscreen is exited.
+//
 // The different states of the class are:
-// - PendingFullscreen: the object is created and is waiting for the associated
-//   <video> to go fullscreen in order to apply an orientation lock;
+// - PendingFullscreen: the object is created and it is either waiting for the
+//   associated <video> to go fullscreen in order to apply an orientation lock,
+//   or it already went fullscreen then the lock was unlocked since the user
+//   rotated their device, and now it is waiting until fullscreen is re-entered;
 // - PendingMetadata: the <video> is fullscreen but the metadata have not been
 //   downloaded yet. It can happen because of network latency or because the
 //   <video> went fullscreen before playback and download started;
 // - MaybeLockedFullscreen: the <video> is fullscreen and a screen orientation
-//   lock was applied.
+//   lock is applied.
 //
 // The possible state transitions are:
 // - PendingFullscreen => PendingMetadata: on fullscreenchange event (entering
 //   fullscreen) when metadata are not available;
 // - PendingFullscreen => MaybeLockedFullscreen: on fullscreenchange event
 //   (entering fullscreen) when metadata are available;
 // - PendingMetadata => MaybeLockedFullscreen: on loadedmetadata;
-// - PendingMetadata => PendingFullscreen: on fullscreenchange event (leaving
+// - PendingMetadata => PendingFullscreen: on fullscreenchange event (exiting
 //   fullscreen);
 // - MaybeLockedFullscreen => PendingFullscreen: on fullscreenchange event
-//   (leaving fullscreen).
+//   (exiting fullscreen) or on deviceorientation event (rotated to match the
+//   orientation of the video).
 class MediaControlsOrientationLockDelegate final : public EventListener {
  public:
   explicit MediaControlsOrientationLockDelegate(HTMLVideoElement&);
 
   // Called by MediaControlsImpl when the HTMLMediaElement is added to a
   // document. All event listeners should be added.
   void Attach();
 
   // Called by MediaControlsImpl when the HTMLMediaElement is no longer in the
   // document. All event listeners should be removed in order to prepare the
@@ skipping 26 matching lines @@
 
   // Locks the screen orientation if the video has metadata information
   // available. Delays locking orientation until metadata are available
   // otherwise.
   void MaybeLockOrientation();
 
   // Unlocks the screen orientation if the screen orientation was previously
   // locked.
   void MaybeUnlockOrientation();
 
+  void MaybeListenToDeviceOrientation();
+  void GotIsAutoRotateEnabledByUser(bool enabled);
+
+  void MaybeUnlockIfDeviceOrientationMatchesVideo(DeviceOrientationEvent*);
+
   // Current state of the object. See comment at the top of the file for a
   // detailed description.
   State state_ = State::kPendingFullscreen;
 
-  // Whether the controls should unlock the screen orientation when possible.
-  // In other words, whether the orientation was locked.
-  bool should_unlock_orientation_ = false;
+  // Which lock is currently applied by this delegate.
+  WebScreenOrientationLockType locked_orientation_ =
+      kWebScreenOrientationLockDefault /* unlocked */;
+
+  device::mojom::blink::ScreenOrientationListenerPtr monitor_;
 
   // `video_element_` owns MediaControlsImpl that owns |this|.
   Member<HTMLVideoElement> video_element_;
 };
 
 }  // namespace blink
 
 #endif  // MediaControlsOrientationLockDelegate_h