#ifndef STAN_MATH_PRIM_MAT_FUN_MDIVIDE_RIGHT_HPP
#define STAN_MATH_PRIM_MAT_FUN_MDIVIDE_RIGHT_HPP

#include <boost/math/tools/promotion.hpp>
#include <stan/math/prim/mat/fun/Eigen.hpp>
#include <stan/math/prim/mat/fun/mdivide_left.hpp>
#include <stan/math/prim/mat/fun/transpose.hpp>
#include <stan/math/prim/mat/err/check_multiplicable.hpp>
#include <stan/math/prim/mat/err/check_square.hpp>

namespace stan {
  namespace math {

    /**
     * Returns the solution of the system Ax=b.
     * @param A Matrix.
     * @param b Right hand side matrix or vector.
     * @return x = b A^-1, solution of the linear system.
     * @throws std::domain_error if A is not square or the rows of b don't
     * match the size of A.
     */
    template <typename T1, typename T2, int R1, int C1, int R2, int C2>
    inline
    Eigen::Matrix<typename boost::math::tools::promote_args<T1, T2>::type,
                  R1, C2>
    mdivide_right(const Eigen::Matrix<T1, R1, C1> &b,
                  const Eigen::Matrix<T2, R2, C2> &A) {
      check_square("mdivide_right", "A", A);
      check_multiplicable("mdivide_right", "b", b, "A", A);
      // FIXME: This is nice and general but likely slow.
      return transpose(mdivide_left(transpose(A), transpose(b)));
      //      return promote_common<Eigen::Matrix<T1, R2, C2>,
      //                            Eigen::Matrix<T2, R2, C2> >(A)
      //        .transpose()
      //        .lu()
      //        .solve(promote_common<Eigen::Matrix<T1, R1, C1>,
      //                              Eigen::Matrix<T2, R1, C1> >(b)
      //               .transpose())
      //        .transpose();
    }

  }
}
#endif
