[FancyZones] Improve code quality (part 4) (#23638)

src/modules/fancyzones/FancyZonesLib/WindowDrag.h

@@ -0,0 +1,47 @@
+#pragma once
+
+#include <FancyZonesLib/HighlightedZones.h>
+
+class WorkArea;
+
+class WindowDrag
+{
+    WindowDrag(HWND window, const std::unordered_map<HMONITOR, std::shared_ptr<WorkArea>>& activeWorkAreas);
+
+public:
+    static std::unique_ptr<WindowDrag> Create(HWND window, const std::unordered_map<HMONITOR, std::shared_ptr<WorkArea>>& activeWorkAreas);
+    ~WindowDrag();
+
+    bool MoveSizeStart(HMONITOR monitor, bool isSnapping);
+    void MoveSizeUpdate(HMONITOR monitor, POINT const& ptScreen, bool isSnapping, bool isSelectManyZonesState);
+    void MoveSizeEnd();
+
+private:
+    void SwitchSnappingMode(bool isSnapping);
+
+    void SetWindowTransparency();
+    void ResetWindowTransparency();
+
+    struct WindowProperties
+    {
+        // True if from the styles the window looks like a standard window
+        bool isStandardWindow = false;
+        // True if the window is a top-level window that does not have a visible owner
+        bool hasNoVisibleOwner = false;
+        // Properties to restore after dragging
+        long exstyle = 0;
+        COLORREF crKey = RGB(0, 0, 0);
+        DWORD dwFlags = 0;
+        BYTE alpha = 0;
+    };
+
+    const HWND m_window;
+    WindowProperties m_windowProperties; // MoveSizeWindowInfo of the window at the moment when dragging started
+    
+    const std::unordered_map<HMONITOR, std::shared_ptr<WorkArea>>& m_activeWorkAreas; // all WorkAreas on current virtual desktop, mapped with monitors
+    std::shared_ptr<WorkArea> m_currentWorkArea; // "Active" WorkArea, where the move/size is happening. Will update as drag moves between monitors.
+    
+    bool m_snappingMode{ false };
+
+    HighlightedZones m_highlightedZones;
+};