feat: add tray layout controls

internal/platform/platform_windows.go

@@ -76,7 +76,9 @@ var (
 	procSetProcessDPIAwareV2     = user32.NewProc("SetProcessDpiAwarenessContext")
 	procEnumDisplayMonitors      = user32.NewProc("EnumDisplayMonitors")
 	procCreateMutex              = kernel32.NewProc("CreateMutexW")
+	procFreeConsole              = kernel32.NewProc("FreeConsole")
 	procDwmGetWindowAttribute    = dwmapi.NewProc("DwmGetWindowAttribute")
+	procMessageBox               = user32.NewProc("MessageBoxW")
 )
 
 type point struct{ X, Y int32 }
@@ -121,10 +123,20 @@ type engine struct {
 	debug           bool
 	overlay         *overlayManager
 	overlayFailed   bool
+	tray            *trayIcon
 }
 
 var activeEngine *engine
 
+func PrepareBackground() { procFreeConsole.Call() }
+
+func ShowError(title, message string) {
+	t, _ := windows.UTF16PtrFromString(title)
+	m, _ := windows.UTF16PtrFromString(message)
+	const mbOKIconErrorSetForeground = 0x00000000 | 0x00000010 | 0x00010000
+	procMessageBox.Call(0, uintptr(unsafe.Pointer(m)), uintptr(unsafe.Pointer(t)), mbOKIconErrorSetForeground)
+}
+
 func Run(configPath string, cfg config.Config, debug bool) error {
 	runtime.LockOSThread()
 	defer runtime.UnlockOSThread()
@@ -142,6 +154,12 @@ func Run(configPath string, cfg config.Config, debug bool) error {
 
 	e := &engine{configPath: configPath, cfg: cfg, hotkeys: make(map[int]hotkeyBinding), debug: debug, overlay: &overlayManager{}}
 	defer e.overlay.hide()
+	tray, err := newTrayIcon(cfg.ActiveLayout, cfg.LayoutNames())
+	if err != nil {
+		return err
+	}
+	e.tray = tray
+	defer e.tray.close()
 	e.rememberConfigTime()
 	activeEngine = e
 	defer func() { activeEngine = nil }()
@@ -690,5 +708,36 @@ func (e *engine) reloadIfChanged() {
 		_ = e.registerHotkeys()
 		return
 	}
+	e.tray.setLayouts(cfg.ActiveLayout, cfg.LayoutNames())
 	log.Printf("configuration reloaded: active layout=%q", cfg.ActiveLayout)
 }
+
+func (e *engine) selectLayout(name string) {
+	e.mu.RLock()
+	cfg := e.cfg
+	e.mu.RUnlock()
+	found := false
+	for _, candidate := range cfg.LayoutNames() {
+		if strings.EqualFold(candidate, name) {
+			name = candidate
+			found = true
+			break
+		}
+	}
+	if !found || strings.EqualFold(cfg.ActiveLayout, name) {
+		return
+	}
+	if err := config.SetActiveLayout(e.configPath, name); err != nil {
+		log.Printf("cannot select layout %q: %v", name, err)
+		ShowError("FancyWin", fmt.Sprintf("Could not select layout %q:\n\n%v", name, err))
+		return
+	}
+	cfg.ActiveLayout = name
+	e.mu.Lock()
+	e.cfg = cfg
+	e.mu.Unlock()
+	e.rememberConfigTime()
+	e.overlay.hide()
+	e.tray.setLayouts(name, cfg.LayoutNames())
+	log.Printf("active layout changed from tray: %q", name)
+}