move windows

#include <windows.h>

/* Declare Windows procedure */
LRESULT CALLBACK WindowProcedure (HWND, UINT, WPARAM, LPARAM);

/* Make the class name into a global variable */
wchar_t szClassName[ ] = L"WindowsApp";

int WINAPI WinMain (HINSTANCE hThisInstance, HINSTANCE hPrevInstance, LPSTR lpszArgument, int nFunsterStil)
{
    HWND hwnd;        /* This is the handle for our window */
    MSG messages;      /* Here messages to the application are saved */
    ZeroMemory(&messages, sizeof(MSG));
    WNDCLASSEX wincl;    /* Data structure for the windowclass */

    /* The Window structure */
    wincl.hInstance = hThisInstance;
    wincl.lpszClassName = szClassName;
    wincl.lpfnWndProc = WindowProcedure;                /* This function is called by windows */
    wincl.style = CS_DBLCLKS;                           /* Catch double-clicks */
    wincl.cbSize = sizeof (WNDCLASSEX);
    wincl.hIcon = LoadIcon (NULL, IDI_APPLICATION);     /* Use default icon and mouse-pointer */
    wincl.hIconSm = LoadIcon (NULL, IDI_APPLICATION);
    wincl.hCursor = LoadCursor (NULL, IDC_ARROW);
    wincl.lpszMenuName = NULL;                          /* No menu */
    wincl.cbClsExtra = 0;                               /* No extra bytes after the window class */
    wincl.cbWndExtra = 0;                               /* structure or the window instance */
    wincl.hbrBackground = (HBRUSH) COLOR_BACKGROUND;  /* Use Windows's default color as the background*/

    /* Register the window class, and if it fails quit the program */
    if (!RegisterClassEx (&wincl))
        return 0;

    /* The class is registered */
    /* WS_EX_TOPMOST - always on top | WS_EX_NOACTIVATE - Prevent mouse input from activating the window*/
    /* WS_POPUPWINDOW - no title bar | WS_SIZEBOX - resizable */
    hwnd = CreateWindowEx (WS_EX_TOPMOST | WS_EX_NOACTIVATE, szClassName, L"App", WS_POPUPWINDOW | WS_SIZEBOX,
        CW_USEDEFAULT, CW_USEDEFAULT, 240, 120, NULL, NULL, hThisInstance, NULL);

    /* Make the window visible on the screen */
    ShowWindow (hwnd, nFunsterStil);

    while(messages.message != WM_QUIT)
    {
        // IF there is a Windows message then process it.
        if(PeekMessage(&messages, 0, 0, 0, PM_REMOVE))
        {
            TranslateMessage(&messages);
            DispatchMessage(&messages);
        }
        // ELSE, do other stuff.
        else
        {
            //SetWindowPos(hwnd, NULL, 0, 0, 0, 0, SWP_NOSIZE | SWP_NOMOVE | SWP_SHOWWINDOW | SWP_NOACTIVATE);
        }
    }

    return messages.wParam;
}


/* This function is called by the Windows function DispatchMessage() */

LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    static int lastMouseX = 0;
    static int lastMouseY = 0;
    switch (message)         /* handle the messages */
    {
    case WM_LBUTTONDOWN:
        lastMouseX = LOWORD(lParam);
        lastMouseY = HIWORD(lParam);
        break;
    case WM_LBUTTONUP:
        break;
    //case WM_NCMOUSEMOVE:
    case WM_MOUSEMOVE:
        if(wParam == MK_LBUTTON)
        {
            int currentMouseX = LOWORD(lParam);
            int currentMouseY = HIWORD(lParam);
            int deltaX = currentMouseX - lastMouseX;
            int deltaY = currentMouseY - lastMouseY;
            RECT prc;
            GetWindowRect(hwnd, &prc);
            SetWindowPos(hwnd, NULL, prc.left + deltaX, prc.top + deltaY, 0, 0, SWP_NOZORDER | SWP_NOSIZE | SWP_NOACTIVATE);
            lastMouseX = currentMouseX;
            lastMouseY = currentMouseY;
        }
        break;
    case WM_DESTROY:
    case WM_RBUTTONUP:
        PostQuitMessage (0);    /* send a WM_QUIT to the message queue */
        break;

    //case WM_MOVING:   /* fix for a bug in windows that prevents contents of the windows from being displayed */
    case WM_SIZING:
        {
            RECT *prc = (RECT *)lParam;
            SetWindowPos(hwnd, NULL, prc->left, prc->top, prc->right - prc->left, prc->bottom - prc->top, 0);
        }
        break;
    default:           /* for messages that we don't deal with */
        return DefWindowProc (hwnd, message, wParam, lParam);
    }

    return 0;
}