fn apply_diff()

in src/platform_impl/windows/window_state.rs [239:336]
85 lines of code
12 McCabe index (conditional complexity)

    fn apply_diff(mut self, window: HWND, mut new: WindowFlags) {
        self = self.mask();
        new = new.mask();

        let diff = self ^ new;
        if diff == WindowFlags::empty() {
            return;
        }

        if diff.contains(WindowFlags::VISIBLE) {
            unsafe {
                winuser::ShowWindow(
                    window,
                    match new.contains(WindowFlags::VISIBLE) {
                        true => winuser::SW_SHOW,
                        false => winuser::SW_HIDE,
                    },
                );
            }
        }
        if diff.contains(WindowFlags::ALWAYS_ON_TOP) {
            unsafe {
                winuser::SetWindowPos(
                    window,
                    match new.contains(WindowFlags::ALWAYS_ON_TOP) {
                        true => winuser::HWND_TOPMOST,
                        false => winuser::HWND_NOTOPMOST,
                    },
                    0,
                    0,
                    0,
                    0,
                    winuser::SWP_ASYNCWINDOWPOS
                        | winuser::SWP_NOMOVE
                        | winuser::SWP_NOSIZE
                        | winuser::SWP_NOACTIVATE,
                );
                winuser::InvalidateRgn(window, ptr::null_mut(), 0);
            }
        }

        if diff.contains(WindowFlags::MAXIMIZED) || new.contains(WindowFlags::MAXIMIZED) {
            unsafe {
                winuser::ShowWindow(
                    window,
                    match new.contains(WindowFlags::MAXIMIZED) {
                        true => winuser::SW_MAXIMIZE,
                        false => winuser::SW_RESTORE,
                    },
                );
            }
        }

        // Minimize operations should execute after maximize for proper window animations
        if diff.contains(WindowFlags::MINIMIZED) {
            unsafe {
                winuser::ShowWindow(
                    window,
                    match new.contains(WindowFlags::MINIMIZED) {
                        true => winuser::SW_MINIMIZE,
                        false => winuser::SW_RESTORE,
                    },
                );
            }
        }

        if diff != WindowFlags::empty() {
            let (style, style_ex) = new.to_window_styles();

            unsafe {
                winuser::SendMessageW(window, *event_loop::SET_RETAIN_STATE_ON_SIZE_MSG_ID, 1, 0);

                // This condition is necessary to avoid having an unrestorable window
                if !new.contains(WindowFlags::MINIMIZED) {
                    winuser::SetWindowLongW(window, winuser::GWL_STYLE, style as _);
                    winuser::SetWindowLongW(window, winuser::GWL_EXSTYLE, style_ex as _);
                }

                let mut flags = winuser::SWP_NOZORDER
                    | winuser::SWP_NOMOVE
                    | winuser::SWP_NOSIZE
                    | winuser::SWP_FRAMECHANGED;

                // We generally don't want style changes here to affect window
                // focus, but for fullscreen windows they must be activated
                // (i.e. focused) so that they appear on top of the taskbar
                if !new.contains(WindowFlags::MARKER_EXCLUSIVE_FULLSCREEN)
                    && !new.contains(WindowFlags::MARKER_BORDERLESS_FULLSCREEN)
                {
                    flags |= winuser::SWP_NOACTIVATE;
                }

                // Refresh the window frame
                winuser::SetWindowPos(window, ptr::null_mut(), 0, 0, 0, 0, flags);
                winuser::SendMessageW(window, *event_loop::SET_RETAIN_STATE_ON_SIZE_MSG_ID, 0, 0);
            }
        }
    }