// 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 op_sp_minus
//! @{

// scalar - SpBase
template <typename T1>
inline void op_sp_minus_pre::apply(Mat<typename T1::elem_type>& out,
                                   const SpToDOp<T1, op_sp_minus_pre>& in) {
  arma_debug_sigprint();

  const SpProxy<T1> P(in.m);

  out.set_size(P.get_n_rows(), P.get_n_cols());
  out.fill(in.aux);

  out -= P.Q;
}

// used for the optimization of sparse % (scalar - sparse)
template <typename eT, typename T2, typename T3>
inline void op_sp_minus_pre::apply_inside_schur(SpMat<eT>& out, const T2& x,
                                                const SpToDOp<T3, op_sp_minus_pre>& y) {
  arma_debug_sigprint();

  const SpProxy<T2> P2(x);
  const SpProxy<T3> P3(y.m);

  arma_conform_assert_same_size(P2.get_n_rows(), P2.get_n_cols(), P3.get_n_rows(),
                                P3.get_n_cols(), "element-wise multiplication");

  out.zeros(P2.get_n_rows(), P2.get_n_cols());

  typename SpProxy<T2>::const_iterator_type it = P2.begin();
  typename SpProxy<T2>::const_iterator_type it_end = P2.end();

  const eT k = y.aux;

  for (; it != it_end; ++it) {
    const uword it_row = it.row();
    const uword it_col = it.col();

    out.at(it_row, it_col) = (*it) * (k - P3.at(it_row, it_col));
  }
}

// used for the optimization of sparse / (scalar - sparse)
template <typename eT, typename T2, typename T3>
inline void op_sp_minus_pre::apply_inside_div(SpMat<eT>& out, const T2& x,
                                              const SpToDOp<T3, op_sp_minus_pre>& y) {
  arma_debug_sigprint();

  const SpProxy<T2> P2(x);
  const SpProxy<T3> P3(y.m);

  arma_conform_assert_same_size(P2.get_n_rows(), P2.get_n_cols(), P3.get_n_rows(),
                                P3.get_n_cols(), "element-wise multiplication");

  out.zeros(P2.get_n_rows(), P2.get_n_cols());

  typename SpProxy<T2>::const_iterator_type it = P2.begin();
  typename SpProxy<T2>::const_iterator_type it_end = P2.end();

  const eT k = y.aux;

  for (; it != it_end; ++it) {
    const uword it_row = it.row();
    const uword it_col = it.col();

    out.at(it_row, it_col) = (*it) / (k - P3.at(it_row, it_col));
  }
}

// SpBase - scalar
template <typename T1>
inline void op_sp_minus_post::apply(Mat<typename T1::elem_type>& out,
                                    const SpToDOp<T1, op_sp_minus_post>& in) {
  arma_debug_sigprint();

  const SpProxy<T1> P(in.m);

  out.set_size(P.get_n_rows(), P.get_n_cols());
  out.fill(-in.aux);

  out += P.Q;
}

// used for the optimization of sparse % (sparse - scalar)
template <typename eT, typename T2, typename T3>
inline void op_sp_minus_post::apply_inside_schur(SpMat<eT>& out, const T2& x,
                                                 const SpToDOp<T3, op_sp_minus_post>& y) {
  arma_debug_sigprint();

  const SpProxy<T2> P2(x);
  const SpProxy<T3> P3(y.m);

  arma_conform_assert_same_size(P2.get_n_rows(), P2.get_n_cols(), P3.get_n_rows(),
                                P3.get_n_cols(), "element-wise multiplication");

  out.zeros(P2.get_n_rows(), P2.get_n_cols());

  typename SpProxy<T2>::const_iterator_type it = P2.begin();
  typename SpProxy<T2>::const_iterator_type it_end = P2.end();

  const eT k = y.aux;

  for (; it != it_end; ++it) {
    const uword it_row = it.row();
    const uword it_col = it.col();

    out.at(it_row, it_col) = (*it) * (P3.at(it_row, it_col) - k);
  }
}

// used for the optimization of sparse / (sparse - scalar)
template <typename eT, typename T2, typename T3>
inline void op_sp_minus_post::apply_inside_div(SpMat<eT>& out, const T2& x,
                                               const SpToDOp<T3, op_sp_minus_post>& y) {
  arma_debug_sigprint();

  const SpProxy<T2> P2(x);
  const SpProxy<T3> P3(y.m);

  arma_conform_assert_same_size(P2.get_n_rows(), P2.get_n_cols(), P3.get_n_rows(),
                                P3.get_n_cols(), "element-wise multiplication");

  out.zeros(P2.get_n_rows(), P2.get_n_cols());

  typename SpProxy<T2>::const_iterator_type it = P2.begin();
  typename SpProxy<T2>::const_iterator_type it_end = P2.end();

  const eT k = y.aux;

  for (; it != it_end; ++it) {
    const uword it_row = it.row();
    const uword it_col = it.col();

    out.at(it_row, it_col) = (*it) / (P3.at(it_row, it_col) - k);
  }
}

//! @}
