#ifndef DVEREB_PROBLEM_H
#define DVEREB_PROBLEM_H

#include <string>
#include <cstdlib>
#include <ncurses.h>

enum PROBLEM_TYPE
{
	// NOTE(dev): EASY means each digit can be handled without carryover.
	//             e.g. 33 + 46 is easy because 3+6 < 10 and 3+4 is < 10.
	//            HARD means you might have to carry over.
	//             e.g. 33 + 97 is hard because 7 + 3 = 10, carry the 1, 9 + 3 + 1 = 13, 130.
	EASY_ADDITION = 1,
	EASY_SUBTRACTION,
	HARD_ADDITION,
	HARD_SUBTRACTION,
};

enum INPUT_STYLE
{
	INPUT_PREPEND = 1,
	INPUT_APPEND,
};

class Problem
{
public:
	Problem(PROBLEM_TYPE type, unsigned short max_digits, unsigned win_x, unsigned win_y);
	~Problem();

	void Draw(bool selected, const INPUT_STYLE &input_style);
	void Input(const INPUT_STYLE input_style, char character);
	void ClearInput() { input = ""; }
	bool Correct() const;

private:
	Problem() = delete;
	static bool seeded;

	PROBLEM_TYPE problem_type;
	WINDOW *win = nullptr;
	unsigned window_x, window_y;

	int number_top;
	int number_bottom;

	int Input() const;
	std::string input;

	// Helper Functions:
	void GenerateNumbers(PROBLEM_TYPE type, unsigned short max_digits);
	void GenerateWindow(unsigned win_x, unsigned win_y);
};

#endif