// Copyright 2013 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 ASH_DISPLAY_DISPLAY_CHANGE_OBSERVER_CHROMEOS_H_
#define ASH_DISPLAY_DISPLAY_CHANGE_OBSERVER_CHROMEOS_H_

#include <stdint.h>

#include <vector>

#include "ash/ash_export.h"
#include "ash/shell_observer.h"
#include "base/macros.h"
#include "ui/display/chromeos/display_configurator.h"
#include "ui/events/devices/input_device_event_observer.h"

namespace ash {

class DisplayInfo;
struct DisplayMode;
class DisplaySnapshot;

// An object that observes changes in display configuration and
// update DisplayManagers.
class DisplayChangeObserver : public ui::DisplayConfigurator::StateController,
                              public ui::DisplayConfigurator::Observer,
                              public ui::InputDeviceEventObserver,
                              public ShellObserver {
 public:
  // Returns the mode list for internal display.
  ASH_EXPORT static std::vector<DisplayMode> GetInternalDisplayModeList(
      const DisplayInfo& display_info,
      const ui::DisplaySnapshot& output);

  // Returns the resolution list.
  ASH_EXPORT static std::vector<DisplayMode> GetExternalDisplayModeList(
      const ui::DisplaySnapshot& output);

  DisplayChangeObserver();
  ~DisplayChangeObserver() override;

  // ui::DisplayConfigurator::StateController overrides:
  ui::MultipleDisplayState GetStateForDisplayIds(
      const ui::DisplayConfigurator::DisplayStateList& outputs) const override;
  bool GetResolutionForDisplayId(int64_t display_id,
                                 gfx::Size* size) const override;

  // Overriden from ui::DisplayConfigurator::Observer:
  void OnDisplayModeChanged(
      const ui::DisplayConfigurator::DisplayStateList& outputs) override;
  void OnDisplayModeChangeFailed(
      const ui::DisplayConfigurator::DisplayStateList& displays,
      ui::MultipleDisplayState failed_new_state) override;

  // Overriden from ui::InputDeviceEventObserver:
  void OnTouchscreenDeviceConfigurationChanged() override;

  // Overriden from ShellObserver:
  void OnAppTerminating() override;

  // Exposed for testing.
  ASH_EXPORT static float FindDeviceScaleFactor(float dpi);

 private:
  DISALLOW_COPY_AND_ASSIGN(DisplayChangeObserver);
};

}  // namespace ash

#endif  // ASH_DISPLAY_DISPLAY_CHANGE_OBSERVER_CHROMEOS_H_