/* ******************************************************************************
 *
 *
 * This program and the accompanying materials are made available under the
 * terms of the Apache License, Version 2.0 which is available at
 * https://www.apache.org/licenses/LICENSE-2.0.
 *
 *  See the NOTICE file distributed with this work for additional
 *  information regarding copyright ownership.
 * 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.
 *
 * SPDX-License-Identifier: Apache-2.0
 ******************************************************************************/

//
// Created by GS <sgazeos@gmail.com> on 3/21/2018.
//
#include <array/ResultSet.h>
#include <execution/Threads.h>
#include <ops/declarable/helpers/matrix_diag_part.h>
#if NOT_EXCLUDED(OP_matrix_diag_part)
namespace sd {
namespace ops {
namespace helpers {

//////////////////////////////////////////////////////////////////////////
// Returns a batched matrix tensor with new batched diagonal values.
// for detailed explanations please take a look on web page:
// https://www.tensorflow.org/api_docs/python/tf/matrix_set_diag
template <typename T>
static sd::Status _matrixDiagPart(NDArray* input, NDArray* output) {
  auto listOut = output->allTensorsAlongDimension({output->rankOf() - 1});
  auto listDiag = input->allTensorsAlongDimension({input->rankOf() - 2, input->rankOf() - 1});

  if (listOut.size() != listDiag.size()) {
    sd_printf("matrix_diag_part: Input matrix has wrong shape.", "");
    return sd::Status::VALIDATION;
  }
  sd::LongType lastDimension = sd::math::sd_min(input->sizeAt(-2), input->sizeAt(-1));
  // TODO: tune this properly
  sd::LongType lO = listOut.size();

  auto func = PRAGMA_THREADS_FOR {
    for (sd::LongType i = start; i < stop; i++)
      for (sd::LongType j = 0; j < lastDimension; ++j) listOut.at(i)->p(j, listDiag.at(i)->e<T>(j, j));
  };

  samediff::Threads::parallel_tad(func, 0, lO);

  return sd::Status::OK;
}

sd::Status matrixDiagPart(sd::LaunchContext* context, NDArray* input, NDArray* output) {
  BUILD_SINGLE_SELECTOR(input->dataType(), return _matrixDiagPart, (input, output), SD_COMMON_TYPES);
}

BUILD_SINGLE_TEMPLATE( sd::Status _matrixDiagPart, (NDArray* input, NDArray* output), SD_COMMON_TYPES);

}  // namespace helpers
}  // namespace ops
}  // namespace sd
#endif