// Copyright (c) 2012 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 CHROME_BROWSER_CHROMEOS_SYSTEM_INPUT_DEVICE_SETTINGS_H_
#define CHROME_BROWSER_CHROMEOS_SYSTEM_INPUT_DEVICE_SETTINGS_H_

#include "base/callback_forward.h"
#include "base/optional.h"
#include "chromeos/chromeos_export.h"

namespace ash {
enum class TouchscreenEnabledSource;
}  // namespace ash

namespace chromeos {
namespace system {

class InputDeviceSettings;

// Min/max possible pointer sensitivity values.
const int kMinPointerSensitivity = 1;
const int kMaxPointerSensitivity = 5;

// Auxiliary class used to update several touchpad settings at a time. User
// should set any number of settings and pass object to UpdateTouchpadSettings
// method of InputDeviceSettings.
// Objects of this class have no default values for settings, so it is error
// to call Get* method before calling corresponding Set* method at least
// once.
class TouchpadSettings {
 public:
  TouchpadSettings();
  TouchpadSettings(const TouchpadSettings& other);
  TouchpadSettings& operator=(const TouchpadSettings& other);

  void SetSensitivity(int value);
  int GetSensitivity() const;
  bool IsSensitivitySet() const;

  void SetTapToClick(bool enabled);
  bool GetTapToClick() const;
  bool IsTapToClickSet() const;

  void SetThreeFingerClick(bool enabled);
  bool GetThreeFingerClick() const;
  bool IsThreeFingerClickSet() const;

  void SetTapDragging(bool enabled);
  bool GetTapDragging() const;
  bool IsTapDraggingSet() const;

  void SetNaturalScroll(bool enabled);
  bool GetNaturalScroll() const;
  bool IsNaturalScrollSet() const;

  // Updates |this| with |settings|. If at least one setting was updated returns
  // true.
  bool Update(const TouchpadSettings& settings);

  // Apply |settings| to input devices.
  static void Apply(const TouchpadSettings& touchpad_settings,
                    InputDeviceSettings* input_device_settings);

 private:
  base::Optional<int> sensitivity_;
  base::Optional<bool> tap_to_click_;
  base::Optional<bool> three_finger_click_;
  base::Optional<bool> tap_dragging_;
  base::Optional<bool> natural_scroll_;
};

// Auxiliary class used to update several mouse settings at a time. User
// should set any number of settings and pass object to UpdateMouseSettings
// method of InputDeviceSettings.
// Objects of this class have no default values for settings, so it is error
// to call Get* method before calling corresponding Set* method at least
// once.
class MouseSettings {
 public:
  MouseSettings();
  MouseSettings(const MouseSettings& other);
  MouseSettings& operator=(const MouseSettings& other);

  void SetSensitivity(int value);
  int GetSensitivity() const;
  bool IsSensitivitySet() const;

  void SetPrimaryButtonRight(bool right);
  bool GetPrimaryButtonRight() const;
  bool IsPrimaryButtonRightSet() const;

  void SetReverseScroll(bool enabled);
  bool GetReverseScroll() const;
  bool IsReverseScrollSet() const;

  // Updates |this| with |settings|. If at least one setting was updated returns
  // true.
  bool Update(const MouseSettings& settings);

  // Apply |settings| to input devices.
  static void Apply(const MouseSettings& mouse_settings,
                    InputDeviceSettings* input_device_settings);

 private:
  base::Optional<int> sensitivity_;
  base::Optional<bool> primary_button_right_;
  base::Optional<bool> reverse_scroll_;
};

// Interface for configuring input device settings.
class CHROMEOS_EXPORT InputDeviceSettings {
 public:
  using DeviceExistsCallback = base::OnceCallback<void(bool)>;

  // Interface for faking touchpad and mouse. Accessed through
  // GetFakeInterface(), implemented only in FakeInputDeviceSettings.
  class FakeInterface {
   public:
    virtual void set_touchpad_exists(bool exists) = 0;
    virtual void set_mouse_exists(bool exists) = 0;
    virtual const TouchpadSettings& current_touchpad_settings() const = 0;
    virtual const MouseSettings& current_mouse_settings() const = 0;
  };

  virtual ~InputDeviceSettings() {}

  // Returns current instance of InputDeviceSettings.
  static InputDeviceSettings* Get();

  // Returns true if UI should implement enhanced keyboard support for cases
  // where other input devices like mouse are absent.
  static bool ForceKeyboardDrivenUINavigation();

  // Calls |callback|, possibly asynchronously, after determining if a touchpad
  // is connected.
  virtual void TouchpadExists(DeviceExistsCallback callback) = 0;

  // Updates several touchpad settings at a time. Updates only settings that
  // are set in |settings| object. It is more efficient to use this method to
  // update several settings then calling Set* methods one by one.
  virtual void UpdateTouchpadSettings(const TouchpadSettings& settings) = 0;

  // Sets the touchpad sensitivity in the range [kMinPointerSensitivity,
  // kMaxPointerSensitivity].
  virtual void SetTouchpadSensitivity(int value) = 0;

  // Turns tap to click on/off.
  virtual void SetTapToClick(bool enabled) = 0;

  // Switch for three-finger click.
  virtual void SetThreeFingerClick(bool enabled) = 0;

  // Turns tap-dragging on/off.
  virtual void SetTapDragging(bool enabled) = 0;

  // Turns natural scrolling on/off for all devices except wheel mice
  virtual void SetNaturalScroll(bool enabled) = 0;

  // Calls |callback|, possibly asynchronously, after determining if a mouse is
  // connected.
  virtual void MouseExists(DeviceExistsCallback callback) = 0;

  // Updates several mouse settings at a time. Updates only settings that
  // are set in |settings| object. It is more efficient to use this method to
  // update several settings then calling Set* methods one by one.
  virtual void UpdateMouseSettings(const MouseSettings& settings) = 0;

  // Sets the mouse sensitivity in the range [kMinPointerSensitivity,
  // kMaxPointerSensitivity].
  virtual void SetMouseSensitivity(int value) = 0;

  // Sets the primary mouse button to the right button if |right| is true.
  virtual void SetPrimaryButtonRight(bool right) = 0;

  // Turns mouse reverse scrolling on/off.
  virtual void SetMouseReverseScroll(bool enabled) = 0;

  // Reapplies previously set touchpad settings.
  virtual void ReapplyTouchpadSettings() = 0;

  // Reapplies previously set mouse settings.
  virtual void ReapplyMouseSettings() = 0;

  // Returns an interface for faking settings, or nullptr.
  virtual FakeInterface* GetFakeInterface() = 0;

 private:
  virtual void SetInternalTouchpadEnabled(bool enabled) {}
  virtual void SetTouchscreensEnabled(bool enabled) {}
};

}  // namespace system
}  // namespace chromeos

#endif  // CHROME_BROWSER_CHROMEOS_SYSTEM_INPUT_DEVICE_SETTINGS_H_