// CWinKeyboardInput.h

#ifndef _CWIN_KEYBOARD_INPUT_H_
#define _CWIN_KEYBOARD_INPUT_H_

#include <memory.h>
#include <winuser.h>

class CWinKeyboardInput 
{
private:
typedef short WINKEYBSTATE[256];
typedef short* LPWINKEYBSTATE;
LPWINKEYBSTATE pck;
LPWINKEYBSTATE pok;
WINKEYBSTATE ks1;
WINKEYBSTATE ks2;
typedef char BYTE;

CWinKeyboardInput()
{
	GetKeyboardState(ks1);
	memcpy(ks2, ks1, sizeof(WINKEYBSTATE) );
	pck = ks1;
	pok = ks2;
}
public:

static CWinKeyboardInput& Get()
{
	static CWinKeyboardInput k;
	CWinKeyboardInput& ref = k;
	return ref;
}

void GetKeyboardState(LPWINKEYBSTATE pks)
{
	for(int vk=0; vk < 256; vk++)
		pks[vk] = GetKeyState(vk);
}

short GetKeyState(BYTE vkey)
{
	return GetAsyncKeyState(vkey);
}

void Update()
{
	LPWINKEYBSTATE tmp = pck;
	pck = pok;
	pok = tmp;
	GetKeyboardState(pck);
}

bool KeyDown(BYTE vkey)
{
	return KeyDown(pck, vkey);
}

bool KeyDown(LPWINKEYBSTATE pk, BYTE vkey)
{
	short DOWNMASK = (short)(1 << (8 * sizeof(short)-1) );
	return ((pk[vkey]&DOWNMASK) != 0);
}

bool KeyUp(BYTE vkey)
{
	return KeyUp(pck, vkey);
}

bool KeyUp(LPWINKEYBSTATE pk, BYTE vkey)
{
	return (!KeyDown(pk, vkey));
}

bool KeyPressed(BYTE vkey)
{
	return ( KeyUp(pok,vkey) && KeyDown(pck,vkey) );
}

bool KeyReleased(BYTE vkey)
{
	return ( KeyDown(pok,vkey) && KeyUp(pck,vkey) );
}

unsigned int VKeyToChar(BYTE vkey)
{
	return ((unsigned int) MapVirtualKey(vkey,2) );
}

short CharToVKey(unsigned char ch)
{
	return ((BYTE) VkKeyScan(ch) );
}

};

#endif

// Cpp file

#include <iostream>
using namespace std;
#include "CWinKeyboardInput.h"

int main()
{
	// create CWinKeyboardInput object
	CWinKeyboardInput::Get();

	while( 1 ){
		CWinKeyboardInput::Get().Update();
		if( CWinKeyboardInput::Get().KeyDown('A') )
			cout << " Key 'a' pressed!! " << endl;
	}
return 0;
}