Continue the implementation of trigger rules (ex scene rules)

pkg/windowmanagerhandler/window_manager_handler_linux.go

@@ -0,0 +1,27 @@
+//go:build linux
+// +build linux
+
+package windowmanagerhandler
+
+import (
+	"context"
+	"os"
+)
+
+type WindowID uint64
+
+type XWMOrWaylandWM interface {
+	WindowFocusChangeChan(ctx context.Context) <-chan WindowFocusChange
+}
+
+type PlatformSpecificWindowManagerHandler struct {
+	XWMOrWaylandWM
+}
+
+func (wmh *WindowManagerHandler) init() error {
+	if os.Getenv("DISPLAY") != "" {
+		return wmh.initUsingXServer()
+	} else {
+		return wmh.initUsingWayland()
+	}
+}