first commit

screenshot_backend.py

@@ -0,0 +1,26 @@
+from abc import ABC, abstractmethod
+
+
+class ScreenshotBackend(ABC):
+    @abstractmethod
+    def supports(self) -> bool:
+        pass
+
+    @abstractmethod
+    def active_window(self) -> str:
+        pass
+
+
+_backends = []
+
+
+def register_backend(cls):
+    _backends.append(cls())
+    return cls
+
+
+def get_backend() -> ScreenshotBackend:
+    for backend in _backends:
+        if backend.supports():
+            return backend
+    raise RuntimeError("No screenshot backend available")