content/renderer/screen_orientation/screen_orientation_dispatcher.h

// Copyright 2014 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 CONTENT_RENDERER_SCREEN_ORIENTATION_SCREEN_ORIENTATION_DISPATCHER_H_
#define CONTENT_RENDERER_SCREEN_ORIENTATION_SCREEN_ORIENTATION_DISPATCHER_H_

#include <memory>
#include <utility>

#include "base/compiler_specific.h"
#include "base/id_map.h"
#include "base/macros.h"
#include "content/public/renderer/render_frame_observer.h"
#include "device/screen_orientation/public/interfaces/screen_orientation.mojom.h"
#include "third_party/WebKit/public/platform/modules/screen_orientation/WebLockOrientationCallback.h"
#include "third_party/WebKit/public/platform/modules/screen_orientation/WebScreenOrientationClient.h"
#include "third_party/WebKit/public/platform/modules/screen_orientation/WebScreenOrientationLockType.h"
#include "third_party/WebKit/public/platform/modules/screen_orientation/WebScreenOrientationType.h"

namespace content {

using device::mojom::ScreenOrientationAssociatedPtr;
using device::mojom::ScreenOrientationLockResult;

class RenderFrame;

// ScreenOrientationDispatcher implements the WebScreenOrientationClient API
// which handles screen lock. It sends lock (or unlock) requests to the browser
// process and listens for responses and let Blink know about the result of the
// request via WebLockOrientationCallback.
class CONTENT_EXPORT ScreenOrientationDispatcher :
    public RenderFrameObserver,
    NON_EXPORTED_BASE(public blink::WebScreenOrientationClient) {
 public:
  explicit ScreenOrientationDispatcher(RenderFrame* render_frame);
  ~ScreenOrientationDispatcher() override;

 private:
  friend class ScreenOrientationDispatcherTest;

  // RenderFrameObserver implementation.
  void OnDestruct() override;

  // blink::WebScreenOrientationClient implementation.
  void lockOrientation(
      blink::WebScreenOrientationLockType orientation,
      std::unique_ptr<blink::WebLockOrientationCallback> callback) override;
  void unlockOrientation() override;

  void OnLockOrientationResult(int request_id,
                               ScreenOrientationLockResult result);

  void CancelPendingLocks();

  int GetRequestIdForTests();

  void EnsureScreenOrientationService();

  // This should only be called by ScreenOrientationDispatcherTest
  void SetScreenOrientationForTests(
      ScreenOrientationAssociatedPtr& screen_orientation_for_tests) {
    screen_orientation_ = std::move(screen_orientation_for_tests);
  }

  // The pending_callbacks_ map is mostly meant to have a unique ID to associate
  // with every callback going trough the dispatcher. The map will own the
  // pointer in the sense that it will destroy it when Remove() will be called.
  // Furthermore, we only expect to have one callback at a time in this map,
  // which is what IDMap was designed for.
  using CallbackMap = IDMap<std::unique_ptr<blink::WebLockOrientationCallback>>;
  CallbackMap pending_callbacks_;

  ScreenOrientationAssociatedPtr screen_orientation_;

  DISALLOW_COPY_AND_ASSIGN(ScreenOrientationDispatcher);
};

}  // namespace content

#endif  // CONTENT_RENDERER_SCREEN_ORIENTATION_SCREEN_ORIENTATION_DISPATCHER_H_