added: input and its subclasses

src/cursor.h

@@ -4,20 +4,25 @@
 #include <ncurses.h>
 #include "position.h"
 
-class cursor{
+// IMPORTANT: use unique_ptr for cursor because:
+//  1. Every instance of cursor will initialize a new ncurses screen
+//     Hence you should only have one instance of cursor at a time
+//     Otherwise IDK what'll happen
+//  2. unique_ptr insures that only one copy of a pre-declared cursor can exist
+class cursor final {
 private:
 public:
-	cursor();
+        cursor();
 
-	~cursor();
+        ~cursor();
 
-	int getcmd() const;
-	
-	void show() const;
+        int getcmd() const;
 
-	void print_char(const position &pos) const;
+        void show() const;
 
-	void print_str(const position &head, const std::string str) const;
+        void print_char(const position &pos) const;
+
+        void print_str(const position &head, const std::string str) const;
 };
 
 #endif