// SPDX-License-Identifier: Apache-2.0
//
// Copyright 2008-2016 Conrad Sanderson (http://conradsanderson.id.au)
// Copyright 2008-2016 National ICT Australia (NICTA)
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ------------------------------------------------------------------------

//! \addtogroup fn_eig_gen
//! @{

template <typename T1>
arma_warn_unused inline
    typename enable_if2<is_supported_blas_type<typename T1::pod_type>::value,
                        Col<std::complex<typename T1::pod_type> > >::result
    eig_gen(const Base<typename T1::elem_type, T1>& expr,
            const char* option = "nobalance") {
  arma_debug_sigprint();

  typedef typename T1::pod_type T;
  typedef typename std::complex<T> eT;

  const char sig = (option != nullptr) ? option[0] : char(0);

  arma_conform_check(((sig != 'n') && (sig != 'b')), "eig_gen(): unknown option");

  if (auxlib::crippled_lapack(expr) && (sig == 'b')) {
    arma_warn(1,
              "eig_gen(): 'balance' option ignored due to linking with crippled lapack");
  }

  Col<eT> eigvals;
  Mat<eT> eigvecs;

  const bool status =
      (sig == 'b') ? auxlib::eig_gen_balance(eigvals, eigvecs, false, expr.get_ref())
                   : auxlib::eig_gen(eigvals, eigvecs, false, expr.get_ref());

  if (status == false) {
    eigvals.soft_reset();
    arma_stop_runtime_error("eig_gen(): decomposition failed");
  }

  return eigvals;
}

template <typename T1>
inline typename enable_if2<is_supported_blas_type<typename T1::pod_type>::value,
                           bool>::result
eig_gen(Col<std::complex<typename T1::pod_type> >& eigvals,
        const Base<typename T1::elem_type, T1>& expr, const char* option = "nobalance") {
  arma_debug_sigprint();

  typedef typename T1::pod_type T;
  typedef typename std::complex<T> eT;

  const char sig = (option != nullptr) ? option[0] : char(0);

  arma_conform_check(((sig != 'n') && (sig != 'b')), "eig_gen(): unknown option");

  if (auxlib::crippled_lapack(expr) && (sig == 'b')) {
    arma_warn(1,
              "eig_gen(): 'balance' option ignored due to linking with crippled lapack");
  }

  Mat<eT> eigvecs;

  const bool status =
      (sig == 'b') ? auxlib::eig_gen_balance(eigvals, eigvecs, false, expr.get_ref())
                   : auxlib::eig_gen(eigvals, eigvecs, false, expr.get_ref());

  if (status == false) {
    eigvals.soft_reset();
    arma_warn(3, "eig_gen(): decomposition failed");
  }

  return status;
}

template <typename T1>
inline typename enable_if2<is_supported_blas_type<typename T1::pod_type>::value,
                           bool>::result
eig_gen(Col<std::complex<typename T1::pod_type> >& eigvals,
        Mat<std::complex<typename T1::pod_type> >& eigvecs,
        const Base<typename T1::elem_type, T1>& expr, const char* option = "nobalance") {
  arma_debug_sigprint();

  arma_conform_check((void_ptr(&eigvals) == void_ptr(&eigvecs)),
                     "eig_gen(): parameter 'eigval' is an alias of parameter 'eigvec'");

  const char sig = (option != nullptr) ? option[0] : char(0);

  arma_conform_check(((sig != 'n') && (sig != 'b')), "eig_gen(): unknown option");

  if (auxlib::crippled_lapack(expr) && (sig == 'b')) {
    arma_warn(1,
              "eig_gen(): 'balance' option ignored due to linking with crippled lapack");
  }

  const bool status =
      (sig == 'b') ? auxlib::eig_gen_balance(eigvals, eigvecs, true, expr.get_ref())
                   : auxlib::eig_gen(eigvals, eigvecs, true, expr.get_ref());

  if (status == false) {
    eigvals.soft_reset();
    eigvecs.soft_reset();
    arma_warn(3, "eig_gen(): decomposition failed");
  }

  return status;
}

template <typename T1>
inline typename enable_if2<is_supported_blas_type<typename T1::pod_type>::value,
                           bool>::result
eig_gen(Col<std::complex<typename T1::pod_type> >& eigvals,
        Mat<std::complex<typename T1::pod_type> >& leigvecs,
        Mat<std::complex<typename T1::pod_type> >& reigvecs,
        const Base<typename T1::elem_type, T1>& expr, const char* option = "nobalance") {
  arma_debug_sigprint();

  arma_conform_check((void_ptr(&eigvals) == void_ptr(&leigvecs)),
                     "eig_gen(): parameter 'eigval' is an alias of parameter 'leigvec'");
  arma_conform_check((void_ptr(&eigvals) == void_ptr(&reigvecs)),
                     "eig_gen(): parameter 'eigval' is an alias of parameter 'reigvec'");
  arma_conform_check((void_ptr(&leigvecs) == void_ptr(&reigvecs)),
                     "eig_gen(): parameter 'leigvec' is an alias of parameter 'reigvec'");

  const char sig = (option != nullptr) ? option[0] : char(0);

  arma_conform_check(((sig != 'n') && (sig != 'b')), "eig_gen(): unknown option");

  if (auxlib::crippled_lapack(expr) && (sig == 'b')) {
    arma_warn(1,
              "eig_gen(): 'balance' option ignored due to linking with crippled lapack");
  }

  const bool status =
      (sig == 'b')
          ? auxlib::eig_gen_twosided_balance(eigvals, leigvecs, reigvecs, expr.get_ref())
          : auxlib::eig_gen_twosided(eigvals, leigvecs, reigvecs, expr.get_ref());

  if (status == false) {
    eigvals.soft_reset();
    leigvecs.soft_reset();
    reigvecs.soft_reset();
    arma_warn(3, "eig_gen(): decomposition failed");
  }

  return status;
}

//! @}
