// 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 CC_SURFACES_DISPLAY_SCHEDULER_H_
#define CC_SURFACES_DISPLAY_SCHEDULER_H_

#include "base/cancelable_callback.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/scoped_ptr.h"
#include "base/single_thread_task_runner.h"
#include "cc/scheduler/begin_frame_source.h"
#include "cc/surfaces/surface_id.h"
#include "cc/surfaces/surfaces_export.h"

namespace cc {

class OutputSurface;
class BeginFrameSource;

class CC_SURFACES_EXPORT DisplaySchedulerClient {
 public:
  virtual ~DisplaySchedulerClient() {}

  virtual bool DrawAndSwap() = 0;
};

class CC_SURFACES_EXPORT DisplayScheduler : public BeginFrameObserverBase {
 public:
  DisplayScheduler(DisplaySchedulerClient* client,
                   BeginFrameSource* begin_frame_source,
                   base::SingleThreadTaskRunner* task_runner,
                   int max_pending_swaps);
  ~DisplayScheduler() override;

  void SetRootSurfaceResourcesLocked(bool locked);
  void ForceImmediateSwapIfPossible();
  virtual void DisplayResized();
  virtual void SetNewRootSurface(SurfaceId root_surface_id);
  virtual void SurfaceDamaged(SurfaceId surface_id);

  virtual void DidSwapBuffers();
  void DidSwapBuffersComplete();

  void OutputSurfaceLost();

  // BeginFrameObserverBase implementation
  bool OnBeginFrameDerivedImpl(const BeginFrameArgs& args) override;
  void OnBeginFrameSourcePausedChanged(bool paused) override;

  BeginFrameSource* begin_frame_source_for_children() {
    return begin_frame_source_for_children_.get();
  }

 protected:
  base::TimeTicks DesiredBeginFrameDeadlineTime();
  virtual void ScheduleBeginFrameDeadline();
  void AttemptDrawAndSwap();
  void OnBeginFrameDeadline();
  void DrawAndSwap();

  DisplaySchedulerClient* client_;
  BeginFrameSource* begin_frame_source_;
  base::SingleThreadTaskRunner* task_runner_;

  BeginFrameArgs current_begin_frame_args_;
  base::Closure begin_frame_deadline_closure_;
  base::CancelableClosure begin_frame_deadline_task_;
  base::TimeTicks begin_frame_deadline_task_time_;

  // TODO(tansell): Set this to something useful.
  scoped_ptr<BeginFrameSource> begin_frame_source_for_children_;

  bool output_surface_lost_;
  bool root_surface_resources_locked_;

  bool inside_begin_frame_deadline_interval_;
  bool needs_draw_;
  bool expecting_root_surface_damage_because_of_resize_;
  bool all_active_child_surfaces_ready_to_draw_;

  int pending_swaps_;
  int max_pending_swaps_;

  bool observing_begin_frame_source_;

  SurfaceId root_surface_id_;
  bool root_surface_damaged_;
  bool expect_damage_from_root_surface_;

  std::set<SurfaceId> child_surface_ids_damaged_;
  std::set<SurfaceId> child_surface_ids_damaged_prev_;
  std::vector<SurfaceId> child_surface_ids_to_expect_damage_from_;

  base::WeakPtrFactory<DisplayScheduler> weak_ptr_factory_;

 private:
  DISALLOW_COPY_AND_ASSIGN(DisplayScheduler);
};

}  // namespace cc

#endif  // CC_SURFACES_DISPLAY_SCHEDULER_H_