#pragma once

#include <cstdint> //uint64_t
//#include <stdexcept> // std::runtime_error

#include "utils/vector.h"
#include "utils/matrix.h"

#include "sum_serial.h"

namespace numerics::detail{
	
	// ---------------- Matrix -> Scalar ----------------
	template <typename T>
	T mean_serial(const utils::Matrix<T>& A) {
	    const uint64_t rows = A.rows();
	    const uint64_t cols = A.cols();
		T sum = detail::sum_serial(A);
		sum /= static_cast<T>(rows*cols);
		return sum;
	}

	// ---------------- Vector -> Scalar ----------------
	template <typename T>
	T mean_serial(const utils::Vector<T>& v) {
		const uint64_t N = v.size();
		T sum = detail::sum_serial(v);
		sum /= static_cast<T>(N);
		return sum;
	}

	// ---------------- Matrix -> Vector ----------------
	template <typename T>
	utils::Vector<T> mean_rowwise_serial(const utils::Matrix<T>& A) {
		const T cols = static_cast<T>(A.cols());
		utils::Vector<T> sum = detail::sum_rowwise_serial(A);
		const uint64_t N = sum.size();
		for (uint64_t i = 0; i < N; ++i){
			sum[i] /= cols;
		}
		return sum;
	}

	template <typename T>
	utils::Vector<T> mean_colwise_serial(const utils::Matrix<T>& A) {
		const T rows = static_cast<T>(A.rows());
		utils::Vector<T> sum = detail::sum_colwise_serial(A);
		const uint64_t N = sum.size();
		for (uint64_t i = 0; i < N; ++i){
			sum[i] /= rows;
		}
		return sum;
	}
} // namespace numerics