#pragma once

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

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

namespace numerics::detail{

	// ---------------- Vector * Vector ----------------
	template <typename T>
	inline T dot_serial(const utils::Vector<T>& v, const utils::Vector<T>& p) {
	    const uint64_t N = v.size();
	    if (N != p.size()) {
	        throw std::runtime_error("dot_serial: dimension mismatch");
	    }
	    T dot_product = T{0};
		for (uint64_t i = 0; i < N; ++i){
			dot_product += v[i]*p[i];
		}
		return dot_product;
	}
	
	// ---------------- Matrix * Vector ----------------
	template <typename T>
	inline utils::Vector<T> dot_serial(const utils::Matrix<T>& A, const utils::Vector<T>& v) {
	    const uint64_t rows = A.rows();
	    const uint64_t cols = A.cols();
	    if (cols != v.size()) {
	        throw std::runtime_error("dot_serial: dimension mismatch");
	    }
	    utils::Vector<T> dot_product(rows, T{0});
		for (uint64_t j = 0; j < cols; ++j){
			for (uint64_t i = 0; i < rows; ++i){
				dot_product[i] += A(i,j)*v[j];
			}
		}
		return dot_product;
	}
} // namespace numerics