// 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 ASH_DISPLAY_DISPLAY_CONTROLLER_H_
#define ASH_DISPLAY_DISPLAY_CONTROLLER_H_

#include <map>
#include <vector>

#include "ash/ash_export.h"
#include "base/basictypes.h"
#include "base/compiler_specific.h"
#include "base/gtest_prod_util.h"
#include "base/memory/scoped_ptr.h"
#include "base/observer_list.h"
#include "base/time.h"
#include "ui/gfx/display_observer.h"
#include "ui/gfx/display.h"

namespace aura {
class Display;
class RootWindow;
}

namespace base {
class Value;
template <typename T> class JSONValueConverter;
}

namespace ash {
namespace internal {
class DisplayManager;
class FocusActivationStore;
class RootWindowController;
}

typedef std::pair<int64, int64> DisplayIdPair;

struct ASH_EXPORT DisplayLayout {
  // Layout options where the secondary display should be positioned.
  enum Position {
    TOP,
    RIGHT,
    BOTTOM,
    LEFT
  };
  // Factory method to create DisplayLayout from ints. The |mirrored| is
  // set to false and |primary_id| is set to gfx::Display::kInvalidDisplayId.
  // Used for persistence and webui.
  static DisplayLayout FromInts(int position, int offsets);

  DisplayLayout();
  DisplayLayout(Position position, int offset);

  // Returns an inverted display layout.
  DisplayLayout Invert() const WARN_UNUSED_RESULT;

  // Converter functions to/from base::Value.
  static bool ConvertFromValue(const base::Value& value, DisplayLayout* layout);
  static bool ConvertToValue(const DisplayLayout& layout, base::Value* value);

  // This method is used by base::JSONValueConverter, you don't need to call
  // this directly. Instead consider using converter functions above.
  static void RegisterJSONConverter(
      base::JSONValueConverter<DisplayLayout>* converter);

  Position position;

  // The offset of the position of the secondary display.  The offset is
  // based on the top/left edge of the primary display.
  int offset;

  // True if displays are mirrored.
  bool mirrored;

  // The id of the display used as a primary display.
  int64 primary_id;

  // Returns string representation of the layout for debugging/testing.
  std::string ToString() const;
};

// DisplayController owns and maintains RootWindows for each attached
// display, keeping them in sync with display configuration changes.
class ASH_EXPORT DisplayController : public gfx::DisplayObserver {
 public:
  class ASH_EXPORT Observer {
   public:
    // Invoked when the display configuration change is requested,
    // but before the change is applied to aura/ash.
    virtual void OnDisplayConfigurationChanging() {}

    // Invoked when the all display configuration changes
    // have been applied.
    virtual void OnDisplayConfigurationChanged() {};

   protected:
    virtual ~Observer() {}
  };

  DisplayController();
  virtual ~DisplayController();

  void Start();
  void Shutdown();

  // Returns primary display. This is safe to use after ash::Shell is
  // deleted.
  static const gfx::Display& GetPrimaryDisplay();

  // Returns the number of display. This is safe to use after
  // ash::Shell is deleted.
  static int GetNumDisplays();

  // True if the primary display has been initialized.
  static bool HasPrimaryDisplay();

  // Initializes primary display.
  void InitPrimaryDisplay();

  // Initialize secondary displays.
  void InitSecondaryDisplays();

  // Add/Remove observers.
  void AddObserver(Observer* observer);
  void RemoveObserver(Observer* observer);

  // Returns the root window for primary display.
  aura::RootWindow* GetPrimaryRootWindow();

  // Returns the root window for |display_id|.
  aura::RootWindow* GetRootWindowForDisplayId(int64 id);

  // Toggle mirror mode.
  void ToggleMirrorMode();

  // Swap primary and secondary display.
  void SwapPrimaryDisplay();

  // Sets the ID of the primary display.  If the display is not connected, it
  // will switch the primary display when connected.
  void SetPrimaryDisplayId(int64 id);

  // Sets primary display. This re-assigns the current root
  // window to given |display|.
  void SetPrimaryDisplay(const gfx::Display& display);

  // Returns the secondary display.
  gfx::Display* GetSecondaryDisplay();

  // Closes all child windows in the all root windows.
  void CloseChildWindows();

  // Returns all root windows. In non extended desktop mode, this
  // returns the primary root window only.
  std::vector<aura::RootWindow*> GetAllRootWindows();

  // Returns all oot window controllers. In non extended desktop
  // mode, this return a RootWindowController for the primary root window only.
  std::vector<internal::RootWindowController*> GetAllRootWindowControllers();

  // Gets/Sets/Clears the overscan insets for the specified |display_id|. See
  // display_manager.h for the details.
  gfx::Insets GetOverscanInsets(int64 display_id) const;
  void SetOverscanInsets(int64 display_id, const gfx::Insets& insets_in_dip);
  void ClearCustomOverscanInsets(int64 display_id);

  const DisplayLayout& default_display_layout() const {
    return default_display_layout_;
  }
  void SetDefaultDisplayLayout(const DisplayLayout& layout);

  // Registeres the display layout info for the specified display(s).
  void RegisterLayoutForDisplayIdPair(int64 id1,
                                      int64 id2,
                                      const DisplayLayout& layout);
  // OBSOLETE
  // TODO(oshima): Remove this in m28.
  void RegisterLayoutForDisplayId(int64 id, const DisplayLayout& layout);

  // Sets the layout for the current display pair. The |layout| specifies
  // the locaion of the secondary display relative to the primary.
  void SetLayoutForCurrentDisplays(const DisplayLayout& layout);

  // Returns the display layout used for current displays.
  DisplayLayout GetCurrentDisplayLayout() const;

  // Returns the current display pair.
  DisplayIdPair GetCurrentDisplayIdPair() const;

  // Returns the display layout registered for the given display id |pair|.
  DisplayLayout GetRegisteredDisplayLayout(const DisplayIdPair& pair) const;

  // Checks if the mouse pointer is on one of displays, and moves to
  // the center of the nearest display if it's outside of all displays.
  void EnsurePointerInDisplays();

  gfx::Point GetNativeMouseCursorLocation() const;

  // Update the current cursor image that is sutable for the given
  // |point_in_native|.
  void UpdateMouseCursor(const gfx::Point& point_in_native);

  // aura::DisplayObserver overrides:
  virtual void OnDisplayBoundsChanged(
      const gfx::Display& display) OVERRIDE;
  virtual void OnDisplayAdded(const gfx::Display& display) OVERRIDE;
  virtual void OnDisplayRemoved(const gfx::Display& display) OVERRIDE;

 private:
  friend class internal::DisplayManager;

  // Creates a root window for |display| and stores it in the |root_windows_|
  // map.
  aura::RootWindow* AddRootWindowForDisplay(const gfx::Display& display);

  void UpdateDisplayBoundsForLayout();

  void NotifyDisplayConfigurationChanging();
  void NotifyDisplayConfigurationChanged();

  void SetLayoutForDisplayIdPair(const DisplayIdPair& display_pair,
                                 const DisplayLayout& layout);

  void RegisterLayoutForDisplayIdPairInternal(
      int64 id1,
      int64 id2,
      const DisplayLayout& layout,
      bool override);

  void OnFadeOutForSwapDisplayFinished();

  bool in_bootstrap() const { return in_bootstrap_; }

  class DisplayChangeLimiter {
   public:
    DisplayChangeLimiter();

    // Sets how long the throttling should last.
    void SetThrottleTimeout(int64 throttle_ms);

    bool IsThrottled() const;

   private:
    // The time when the throttling ends.
    base::Time throttle_timeout_;

    DISALLOW_COPY_AND_ASSIGN(DisplayChangeLimiter);
  };

  // The limiter to throttle how fast a user can
  // change the display configuration.
  scoped_ptr<DisplayChangeLimiter> limiter_;

  // The mapping from display ID to its root window.
  std::map<int64, aura::RootWindow*> root_windows_;

  // The default display layout.
  DisplayLayout default_display_layout_;

  // Display layout per pair of devices.
  std::map<DisplayIdPair, DisplayLayout> paired_layouts_;

  ObserverList<Observer> observers_;

  // Store the primary root window temporarily while replacing
  // display.
  aura::RootWindow* primary_root_window_for_replace_;

  bool in_bootstrap_;

  scoped_ptr<internal::FocusActivationStore> focus_activation_store_;

  DISALLOW_COPY_AND_ASSIGN(DisplayController);
};

}  // namespace ash

#endif  // ASH_DISPLAY_DISPLAY_CONTROLLER_H_