/* ******************************************************************************
 *
 *
 * 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
 ******************************************************************************/

//
//  @author raver119@gmail.com
//
#include <execution/Threads.h>
#include <ops/declarable/helpers/helpers.h>

namespace sd {
namespace ops {
namespace helpers {

SD_LIB_HIDDEN void crossBatched(LaunchContext *context, NDArray *a, NDArray *b, NDArray *o);

void SD_INLINE cross(LaunchContext *context, NDArray *a, NDArray *b, NDArray *o) {
  if (a->isR()) {
#ifdef HAS_DOUBLE
    auto a0 = a->e<double>(0);
    auto a1 = a->e<double>(1);
    auto a2 = a->e<double>(2);

    auto b0 = b->e<double>(0);
    auto b1 = b->e<double>(1);
    auto b2 = b->e<double>(2);

    o->p(LongType(0L), static_cast<double>(a1 * b2 - a2 * b1));
    o->p(1L, static_cast<double>(a2 * b0 - a0 * b2));
    o->p(2L, static_cast<double>(a0 * b1 - a1 * b0));
#elif defined(HAS_FLOAT32)
    auto a0 = a->e<float>(0);
    auto a1 = a->e<float>(1);
    auto a2 = a->e<float>(2);

    auto b0 = b->e<float>(0);
    auto b1 = b->e<float>(1);
    auto b2 = b->e<float>(2);

    o->p(LongType(0L), static_cast<float>(a1 * b2 - a2 * b1));
    o->p(1L, static_cast<float>(a2 * b0 - a0 * b2));
    o->p(2L, static_cast<float>(a0 * b1 - a1 * b0));
#else
#error "No floating-point type available for cross product operation"
#endif
  } else {
    auto a0 = a->e<LongType>(0);
    auto a1 = a->e<LongType>(1);
    auto a2 = a->e<LongType>(2);

    auto b0 = b->e<LongType>(0);
    auto b1 = b->e<LongType>(1);
    auto b2 = b->e<LongType>(2);

    o->p(LongType(0L), a1 * b2 - a2 * b1);
    o->p(1L, a2 * b0 - a0 * b2);
    o->p(2L, a0 * b1 - a1 * b0);
  }
}

void SD_INLINE _crossBatched(LaunchContext *context, NDArray *a, NDArray *b, NDArray *o) {
  std::vector<sd::LongType> reshape = {-1,3};
  auto a_ = a->reshape(a->ordering(), reshape);
  auto b_ = b->reshape(b->ordering(), reshape);
  auto o_ = o->reshape(o->ordering(),reshape, false);

  auto tadsA = a_->allTensorsAlongDimension({1});
  auto tadsB = b_->allTensorsAlongDimension({1});
  auto tadsO = o_->allTensorsAlongDimension({1});

  int tads = tadsA.size();

  auto func = PRAGMA_THREADS_FOR {
    for (auto e = start; e < stop; e++) {
      auto a_ = tadsA.at(e);
      auto b_ = tadsB.at(e);
      auto o_ = tadsO.at(e);

      cross(context, a_, b_, o_);
    }
  };

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

  delete a_;
  delete b_;
  delete o_;
}

void weightedCrossEntropyWithLogitsFunctor(LaunchContext *context, NDArray *targets, NDArray *input,
                                           NDArray *weights, NDArray *output);
}  // namespace helpers
}  // namespace ops
}  // namespace sd