Программа клиент-сервер

struct MonitorEnumProc_data
{
    int min_s;
    RECT window;
    RECT monitor;
};
 
static BOOL CALLBACK MonitorEnumProc
(
    HMONITOR hMonitor,
    HDC hdcMonitor,
    LPRECT lprcMonitor,
    LPARAM dwData
)
{
    MonitorEnumProc_data *data = (MonitorEnumProc_data *)dwData;
 
    int left = data->window.left > lprcMonitor->left? data->window.left : lprcMonitor->left;
    int right = data->window.right < lprcMonitor->right? data->window.right : lprcMonitor->right;
    int bottom = data->window.bottom < lprcMonitor->bottom? data->window.bottom : lprcMonitor->bottom;
    int top = data->window.top > lprcMonitor->top? data->window.top : lprcMonitor->top;
 
    if (left < right && bottom > top)
    {
        int min_s = (right - left) * (bottom - top);
        if (min_s > data->min_s)
        {
            data->min_s = min_s;
            data->monitor = *lprcMonitor;
        }
    }
}
 
static void get_selected_display_metrics
(
    const HWND hwnd,
    int * const x,
    int * const y,
    int * const w,
    int * const h
)
{
    MonitorEnumProc_data data = {-1, {0, 0, 0, 0}, {0, 0, 0, 0}};
 
    *x = 0;
    *y = 0;
    *w = GetSystemMetrics(SM_CXSCREEN);
    *h = GetSystemMetrics(SM_CYSCREEN);
 
    GetWindowRect(hwnd, &data.window);
 
    EnumDisplayMonitors(0, 0, MonitorEnumProc, (LPARAM)&data);
 
    if (data.min_s > 0)
    {
        *x = data.monitor.left;
        *y = data.monitor.top;
        *w = data.monitor.right - data.monitor.left;
        *h = data.monitor.bottom - data.monitor.top;
    }
}

void __fastcall Tmain_form::ImageDblClick(TObject *Sender)
{
    static bool full_screen_mode = false;
    full_screen_mode = !full_screen_mode;
    static WINDOWPLACEMENT wp;
    if (full_screen_mode)
    {
        GetWindowPlacement(Handle, &wp);
        SetWindowLong(Handle, GWL_STYLE, -1778384896L);
 
        int x, y, w, h;
 
        get_selected_display_metrics(Handle, &x, &y, &w, &h);
 
        Left = x;
        Top = y;
        Width = w;
        Height = h;
    }
    else
    {
        SetWindowLong(Handle, GWL_STYLE, 382664704L);
        SetWindowPlacement(Handle, &wp);
    }
}