/* *****************************************************************************
 * %{QMAKE_PROJECT_NAME}
 * Copyright (c) %YEAR% killerbee
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 * ****************************************************************************/
#ifndef TWO_CANDLES_PROBLEM_H
#define TWO_CANDLES_PROBLEM_H

#include <kblib/random.h>
#include <utility>

inline auto rng = kblib::seeded<std::mt19937>();
template <typename T = double>
inline auto uniform_01 = std::uniform_real_distribution<T>{0, 1};

template <typename T = double>
struct minmax_result {
	T min;
	T max;
	friend auto operator+(minmax_result lhs, minmax_result rhs)
	    -> minmax_result {
		return {lhs.min + rhs.min, lhs.max + rhs.max};
	}
	friend auto operator/(minmax_result lhs, T d) -> minmax_result {
		return {lhs.min / d, lhs.max / d};
	}
};

template <typename T = double>
auto get_avg_positions_ab(int iterations_lb2) -> minmax_result<T> {
	if (iterations_lb2 == 0) {
		return {};
	} else if (iterations_lb2 == 1) {
		auto a = uniform_01<T>(rng);
		auto b = uniform_01<T>(rng);
		return {std::min(a, b), std::max(a, b)};
	} else {
		return (get_avg_positions_ab<T>(iterations_lb2 - 1)
		        + get_avg_positions_ab<T>(iterations_lb2 - 1))
		       / 2;
	}
}

#endif // TWO_CANDLES_PROBLEM_H