1 files changed, 48 insertions, 0 deletions
diff --git a/c/drag.h b/c/drag.h
new file mode 100644
index 0000000..ac97090
--- /dev/null
+++ b/c/drag.h
@@ -0,0 +1,48 @@
+#ifndef DRAG_H
+#define DRAG_H
+
+#include <windows.h>
+
+/* Dragger objects implement draggable portions of the client area,
+ * such as the split between two list views. HandleLButtonDown and
+ * HandleSetCursor are called by relevant window procedures upon
+ * WM_(NC)LBUTTONDOWN and WM_SETCURSOR. */
+
+struct Window;
+
+struct Dragger
+{
+	Window& parent;
+	bool HandleLButtonDown();
+	bool HandleSetCursor();
+	inline Dragger(Window& parent) : parent(parent) {}
+protected:
+	bool IsDown() const;
+	bool IsDouble(const long time, const POINT& pt);
+	virtual bool InDragArea(int x, int y) const = 0;
+	/* Perform drag, resizing relevant windows. */
+	virtual void Drag(int x, int y) const = 0;
+	/* Reset dragger to automatic position. */
+	virtual void Reset() const = 0;
+	/* Called after drag, when mouse button is released. */
+	virtual void Done() const = 0;
+private:
+	bool m_bActive = false;
+	long m_time0 = 0;
+	POINT m_pt0 = {0, 0};
+};
+
+/* DlvDragger implements the draggable split between the data list
+ * view and the episode list view. */
+
+struct DlvDragger : public Dragger
+{
+	inline DlvDragger(Window& parent) : Dragger(parent) {}
+private:
+	bool InDragArea(int x, int y) const override;
+	void Drag(int x, int y) const override;
+	void Reset() const override;
+	void Done() const override;
+};
+
+#endif