Fix #163

Author: wangwenx190

src/core/contexts/win32windowcontext.cpp

@@ -219,12 +219,16 @@ namespace QWK {
             return true;
         }
 
+        const auto windowStyles = ::GetWindowLongPtrW(hWnd, GWL_STYLE);
+        const bool allowMaximize = windowStyles & WS_MAXIMIZEBOX;
+        const bool allowMinimize = windowStyles & WS_MINIMIZEBOX;
+
         const bool maxOrFull = isMaximized(hWnd) || isFullScreen(hWnd);
         ::EnableMenuItem(hMenu, SC_CLOSE, (MF_BYCOMMAND | MFS_ENABLED));
         ::EnableMenuItem(hMenu, SC_MAXIMIZE,
-                         (MF_BYCOMMAND | ((maxOrFull || fixedSize) ? MFS_DISABLED : MFS_ENABLED)));
+                         (MF_BYCOMMAND | ((maxOrFull || fixedSize || !allowMaximize) ? MFS_DISABLED : MFS_ENABLED)));
         ::EnableMenuItem(hMenu, SC_RESTORE,
-                         (MF_BYCOMMAND | ((maxOrFull && !fixedSize) ? MFS_ENABLED : MFS_DISABLED)));
+                         (MF_BYCOMMAND | ((maxOrFull && !fixedSize && allowMaximize) ? MFS_ENABLED : MFS_DISABLED)));
         // The first menu item should be selected by default if the menu is brought
         // up by keyboard. I don't know how to pre-select a menu item but it seems
         // highlight can do the job. However, there's an annoying issue if we do
@@ -236,7 +240,7 @@ namespace QWK {
         // the menu look kind of weird. Currently I don't know how to fix this issue.
         ::HiliteMenuItem(hWnd, hMenu, SC_RESTORE,
                          (MF_BYCOMMAND | (selectFirstEntry ? MFS_HILITE : MFS_UNHILITE)));
-        ::EnableMenuItem(hMenu, SC_MINIMIZE, (MF_BYCOMMAND | MFS_ENABLED));
+        ::EnableMenuItem(hMenu, SC_MINIMIZE, (MF_BYCOMMAND | (allowMinimize ? MFS_ENABLED : MFS_DISABLED)));
         ::EnableMenuItem(hMenu, SC_SIZE,
                          (MF_BYCOMMAND | ((maxOrFull || fixedSize) ? MFS_DISABLED : MFS_ENABLED)));
         ::EnableMenuItem(hMenu, SC_MOVE, (MF_BYCOMMAND | (maxOrFull ? MFS_DISABLED : MFS_ENABLED)));