feat: input handler work

include/input.h

@@ -0,0 +1,33 @@
+#pragma once
+#ifndef H_INPUT_
+#define H_INPUT_
+
+#include <cstddef>
+
+class InputHandlerImpl {
+public:
+	InputHandlerImpl() = default;
+	virtual ~InputHandlerImpl() = default;
+
+public:
+	virtual size_t GetMouseX() = 0;
+	virtual size_t GetMouseY() = 0;
+};
+
+class InputHandler {
+public:
+	static InputHandler* GetInstance() {
+		if (!s_instance) s_instance = new InputHandler;
+		return s_instance;
+	}
+private:
+	InputHandler();
+public:
+	size_t GetMouseX();
+	size_t GetMouseY();
+private:
+	static InputHandler* s_instance;
+	InputHandlerImpl* m_impl;
+};
+
+#endif // H_INPUT_