[FancyZones] Improve code quality (part 3: window dragging) (#23040)

src/modules/fancyzones/FancyZonesLib/DraggingState.h

@@ -0,0 +1,30 @@
+#pragma once
+
+#include <FancyZonesLib/KeyState.h>
+#include <FancyZonesLib/SecondaryMouseButtonsHook.h>
+
+class DraggingState
+{
+public:
+    DraggingState(const std::function<void()>& keyUpdateCallback);
+    ~DraggingState() = default;
+
+    void Enable();
+    void Disable();
+    void UpdateDraggingState() noexcept;
+
+    bool IsDragging() const noexcept;
+    bool IsSelectManyZonesState() const noexcept;
+
+private:
+    void OnMouseDown();
+
+    std::atomic<bool> m_mouseState;
+    SecondaryMouseButtonsHook m_mouseHook;
+    KeyState<VK_LSHIFT> m_leftShiftKeyState;
+    KeyState<VK_RSHIFT> m_rightShiftKeyState;
+    KeyState<VK_LCONTROL, VK_RCONTROL> m_ctrlKeyState;
+    std::function<void()> m_keyUpdateCallback;
+
+    bool m_dragging{}; // True if we should be showing zone hints while dragging
+};