/*
 * Deskflow -- mouse and keyboard sharing utility
 * SPDX-FileCopyrightText: (C) 2012 - 2016 Symless Ltd.
 * SPDX-FileCopyrightText: (C) 2003 Chris Schoeneman
 * SPDX-License-Identifier: GPL-2.0-only WITH LicenseRef-OpenSSL-Exception
 */

#pragma once

#include "deskflow/KeyState.h"

#include <string>
#include <vector>

#define WIN32_LEAN_AND_MEAN
#include <Windows.h>

class Event;
class EventQueueTimer;
class MSWindowsDesks;
class IEventQueue;

//! Microsoft Windows key mapper
/*!
This class maps KeyIDs to keystrokes.
*/
class MSWindowsKeyState : public KeyState
{
public:
  MSWindowsKeyState(
      MSWindowsDesks *desks, void *eventTarget, IEventQueue *events, std::vector<std::string> layouts,
      bool isLangSyncEnabled
  );
  MSWindowsKeyState(
      MSWindowsDesks *desks, void *eventTarget, IEventQueue *events, deskflow::KeyMap &keyMap,
      std::vector<std::string> layouts, bool isLangSyncEnabled
  );
  virtual ~MSWindowsKeyState();

  //! @name manipulators
  //@{

  //! Handle screen disabling
  /*!
  Called when screen is disabled.  This is needed to deal with platform
  brokenness.
  */
  void disable();

  //! Set the active keyboard layout
  /*!
  Uses \p keyLayout when querying the keyboard.
  */
  void setKeyLayout(HKL keyLayout);

  //! Test and set autorepeat state
  /*!
  Returns true if the given button is autorepeating and updates internal
  state.
  */
  bool testAutoRepeat(bool press, bool isRepeat, KeyButton);

  //! Remember modifier state
  /*!
  Records the current non-toggle modifier state.
  */
  void saveModifiers();

  //! Set effective modifier state
  /*!
  Temporarily sets the non-toggle modifier state to those saved by the
  last call to \c saveModifiers if \p enable is \c true.  Restores the
  modifier state to the current modifier state if \p enable is \c false.
  This is for synthesizing keystrokes on the primary screen when the
  cursor is on a secondary screen.  When on a secondary screen we capture
  all non-toggle modifier state, track the state internally and do not
  pass it on.  So if Alt+F1 synthesizes Alt+X we need to synthesize
  not just X but also Alt, despite the fact that our internal modifier
  state indicates Alt is down, because local apps never saw the Alt down
  event.
  */
  void useSavedModifiers(bool enable);

  //@}
  //! @name accessors
  //@{

  //! Map a virtual key to a button
  /*!
  Returns the button for the \p virtualKey.
  */
  KeyButton virtualKeyToButton(UINT virtualKey) const;

  //! Map key event to a key
  /*!
  Converts a key event into a KeyID and the shadow modifier state
  to a modifier mask.
  */
  KeyID mapKeyFromEvent(WPARAM charAndVirtKey, LPARAM info, KeyModifierMask *maskOut) const;

  //! Check if keyboard groups have changed
  /*!
  Returns true iff the number or order of the keyboard groups have
  changed since the last call to updateKeys().
  */
  bool didGroupsChange() const;

  //! Map key to virtual key
  /*!
  Returns the virtual key for key \p key or 0 if there's no such virtual
  key.
  */
  UINT mapKeyToVirtualKey(KeyID key) const;

  //! Map virtual key and button to KeyID
  /*!
  Returns the KeyID for virtual key \p virtualKey and button \p button
  (button should include the extended key bit), or kKeyNone if there is
  no such key.
  */
  KeyID getKeyID(UINT virtualKey, KeyButton button) const;

  //! Map button to virtual key
  /*!
  Returns the virtual key for button \p button
  (button should include the extended key bit), or kKeyNone if there is
  no such key.
  */
  UINT mapButtonToVirtualKey(KeyButton button) const;

  //@}

  // IKeyState overrides
  void fakeKeyDown(KeyID id, KeyModifierMask mask, KeyButton button, const std::string &lang) override;
  bool fakeKeyRepeat(KeyID id, KeyModifierMask mask, int32_t count, KeyButton button, const std::string &lang) override;
  bool fakeCtrlAltDel() override;
  KeyModifierMask pollActiveModifiers() const override;
  int32_t pollActiveGroup() const override;
  void pollPressedKeys(KeyButtonSet &pressedKeys) const override;

  // KeyState overrides
  void onKey(KeyButton button, bool down, KeyModifierMask newState) override;
  void sendKeyEvent(
      void *target, bool press, bool isAutoRepeat, KeyID key, KeyModifierMask mask, int32_t count, KeyButton button
  ) override;

  // Unit test accessors
  KeyButton getLastDown() const
  {
    return m_lastDown;
  }
  void setLastDown(KeyButton value)
  {
    m_lastDown = value;
  }
  KeyModifierMask getSavedModifiers() const
  {
    return m_savedModifiers;
  }
  void setSavedModifiers(KeyModifierMask value)
  {
    m_savedModifiers = value;
  }

protected:
  // KeyState overrides
  void getKeyMap(deskflow::KeyMap &keyMap) override;
  void fakeKey(const Keystroke &keystroke) override;
  KeyModifierMask &getActiveModifiersRValue() override;

private:
  using GroupList = std::vector<HKL>;

  bool getGroups(GroupList &) const;
  void setWindowGroup(int32_t group);

  KeyID getIDForKey(deskflow::KeyMap::KeyItem &item, KeyButton button, UINT virtualKey, PBYTE keyState, HKL hkl) const;

  void addKeyEntry(deskflow::KeyMap &keyMap, deskflow::KeyMap::KeyItem &item);

  void init();

private:
  // not implemented
  MSWindowsKeyState(const MSWindowsKeyState &);
  MSWindowsKeyState &operator=(const MSWindowsKeyState &);

private:
  using GroupMap = std::map<HKL, int32_t>;
  using KeyToVKMap = std::map<KeyID, UINT>;

  void *m_eventTarget;
  MSWindowsDesks *m_desks;
  HKL m_keyLayout;
  UINT m_buttonToVK[512];
  UINT m_buttonToNumpadVK[512];
  KeyButton m_virtualKeyToButton[256];
  KeyToVKMap m_keyToVKMap;
  IEventQueue *m_events;

  // the timer used to check for fixing key state
  EventQueueTimer *m_fixTimer;

  // the groups (keyboard layouts)
  GroupList m_groups;
  GroupMap m_groupMap;

  // the last button that we generated a key down event for.  this
  // is zero if the last key event was a key up.  we use this to
  // synthesize key repeats since the low level keyboard hook can't
  // tell us if an event is a key repeat.
  KeyButton m_lastDown;

  // modifier tracking
  bool m_useSavedModifiers;
  KeyModifierMask m_savedModifiers;
  KeyModifierMask m_originalSavedModifiers;

  // pointer to ToUnicodeEx.  on win95 family this will be nullptr.
  typedef int(WINAPI *ToUnicodeEx_t)(
      UINT wVirtKey, UINT wScanCode, PBYTE lpKeyState, LPWSTR pwszBuff, int cchBuff, UINT wFlags, HKL dwhkl
  );
  ToUnicodeEx_t m_ToUnicodeEx;

  static const KeyID s_virtualKey[];
};