#include <Windows.h>
#include <string>

const WCHAR g_szClassName[]= L"TestProgram";

HINSTANCE	g_hInstance;
HWND g_hwnd;
INT g_nCount;

DWORD g_dwStyle= WS_CLIPCHILDREN | WS_CLIPSIBLINGS | WS_DLGFRAME | WS_POPUP;
DWORD g_dwExStyle= WS_EX_TOPMOST | WS_EX_WINDOWEDGE ;

std::wstring g_str;
std::wstring c_str;

LRESULT CALLBACK
WindowProc (HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
		RECT rc;
		RECT rcl;
		HDC hdc ;
		HWND hChild;
		PAINTSTRUCT ps ;

		switch(uMsg)
		{

		case WM_CREATE:
			if (g_nCount < 4)
			{	
				g_nCount++;
				GetWindowRect(hwnd,&rc);
				hChild= CreateWindowEx(
						g_dwExStyle, g_szClassName, g_szClassName, g_dwStyle,
						rc.left+10, rc.top+10, 100, 100,
						hwnd, NULL, g_hInstance, NULL);
				ShowWindow(hChild, SW_SHOW);
				UpdateWindow(hChild);
			}
			else
			{
				SetTimer(hwnd,999,5000,NULL);
			}
			break;

		case WM_PAINT:
		  WCHAR cl[600];
          hdc = BeginPaint (hwnd, &ps) ;
		  wsprintf(cl,L"%i",hwnd);
          GetClientRect (hwnd, &rcl) ;
          
          DrawText (hdc, cl, -1, &rcl,
                    DT_SINGLELINE | DT_CENTER | DT_VCENTER) ;
          EndPaint (hwnd, &ps) ;
          return 0 ;

		case WM_TIMER:
			if(wParam==999)
			{
				KillTimer(hwnd,999);
				HWND hParent=GetParent(hwnd);
				HWND hPrev;
				WCHAR chwnd[200];
		

				if(hParent)
				{
					hPrev=SetActiveWindow(hParent);
					DestroyWindow(hwnd);
					wsprintf(chwnd,L"EXTRA hPrev: %i \n hwnd: %i \n hParent: %i \n GetActiveWindow: %i \n",hPrev,hwnd,hParent, GetActiveWindow());
					g_str +=chwnd;
					if(GetActiveWindow()==hParent)
					{
						g_str +=L"success \n\n";
						
					}
					else
					{	
						g_str +=L"failure \n\n";
					}
					SetTimer(hParent,999,5000,NULL);
				}
				else
				{
					DestroyWindow(hwnd);
					PostQuitMessage(0);
				}
			}
			break;

		default:
			return DefWindowProc(hwnd, uMsg, wParam, lParam);
		}
		return 0;
}

INT WINAPI
WinMain(HINSTANCE hInstance,
		HINSTANCE hPrecInstance,
		LPSTR	pszCmdLine,
		INT nCmdShow)
{
	g_hInstance = hInstance;
	WNDCLASSW wc;
	wc.style=0;
	wc.lpfnWndProc=WindowProc;
	wc.cbClsExtra=0;
	wc.cbWndExtra=0;
	wc.hInstance=hInstance;
	wc.hIcon=LoadIcon(NULL,IDI_APPLICATION);
	wc.hCursor=LoadCursor(NULL,IDC_ARROW);
	wc.hbrBackground=(HBRUSH)(COLOR_3DFACE +1);
	wc.lpszClassName=g_szClassName;
	if(!RegisterClass(&wc))
	{
		MessageBoxW(NULL, L"Error: register class",NULL, MB_ICONERROR);
		return 1;
	}
	
	g_hwnd= CreateWindowExW(g_dwExStyle,g_szClassName, g_szClassName, g_dwStyle,
							CW_USEDEFAULT,CW_USEDEFAULT,300,300,
							NULL,NULL,hInstance, NULL);
	
	g_nCount=0;
	


	if (g_hwnd == NULL)
	{
		MessageBoxW(NULL, L"Error: create Window", NULL, MB_ICONERROR);
		return 2;
	}
	ShowWindow(g_hwnd, SW_SHOW);
	UpdateWindow(g_hwnd);

	MSG msg;
	while (GetMessage(&msg,NULL,0,0))
	{
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}
	MessageBoxW(NULL, g_str.c_str(), L"result", MB_ICONINFORMATION);

	return (INT)msg.wParam;
}