// Ceres Solver - A fast non-linear least squares minimizer

// Copyright 2015 Google Inc. All rights reserved.

// http://ceres-solver.org/

//

// Redistribution and use in source and binary forms, with or without

// modification, are permitted provided that the following conditions are met:

//

// * Redistributions of source code must retain the above copyright notice,

//   this list of conditions and the following disclaimer.

// * Redistributions in binary form must reproduce the above copyright notice,

//   this list of conditions and the following disclaimer in the documentation

//   and/or other materials provided with the distribution.

// * Neither the name of Google Inc. nor the names of its contributors may be

//   used to endorse or promote products derived from this software without

//   specific prior written permission.

//

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE

// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

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// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

// POSSIBILITY OF SUCH DAMAGE.

//

// Author: sameragarwal@google.com (Sameer Agarwal)

#include "ceres/callbacks.h"

#include "ceres/gradient_checking_cost_function.h"

#include "ceres/line_search_preprocessor.h"

#include "ceres/preprocessor.h"

#include "ceres/problem_impl.h"

#include "ceres/solver.h"

#include "ceres/trust_region_preprocessor.h"

namespace ceres {

namespace internal {

Preprocessor* Preprocessor::Create(MinimizerType minimizer_type) {

  if (minimizer_type == TRUST_REGION) {

    return new TrustRegionPreprocessor;

  }

  if (minimizer_type == LINE_SEARCH) {

    return new LineSearchPreprocessor;

  }

  LOG(FATAL) << "Unknown minimizer_type: " << minimizer_type;

  return NULL;

}

Preprocessor::~Preprocessor() {

}

void ChangeNumThreadsIfNeeded(Solver::Options* options) {

#ifndef CERES_USE_OPENMP

  if (options->num_threads > 1) {

    LOG(WARNING)

        << "OpenMP support is not compiled into this binary; "

        << "only options.num_threads = 1 is supported. Switching "

        << "to single threaded mode.";

    options->num_threads = 1;

  }

  // Only the Trust Region solver currently uses a linear solver.

  if (options->minimizer_type == TRUST_REGION &&

      options->num_linear_solver_threads > 1) {

    LOG(WARNING)

        << "OpenMP support is not compiled into this binary; "

        << "only options.num_linear_solver_threads=1 is supported. Switching "

        << "to single threaded mode.";

    options->num_linear_solver_threads = 1;

  }

#endif  // CERES_USE_OPENMP

}

void SetupCommonMinimizerOptions(PreprocessedProblem* pp) {

  const Solver::Options& options = pp->options;

  Program* program = pp->reduced_program.get();

  // Assuming that the parameter blocks in the program have been

  // reordered as needed, extract them into a contiguous vector.

  pp->reduced_parameters.resize(program->NumParameters());

  double* reduced_parameters = pp->reduced_parameters.data();

  program->ParameterBlocksToStateVector(reduced_parameters);

  Minimizer::Options& minimizer_options = pp->minimizer_options;

  minimizer_options = Minimizer::Options(options);

  minimizer_options.evaluator = pp->evaluator;

  if (options.logging_type != SILENT) {

    pp->logging_callback.reset(

        new LoggingCallback(options.minimizer_type,

                            options.minimizer_progress_to_stdout));

    minimizer_options.callbacks.insert(minimizer_options.callbacks.begin(),

                                       pp->logging_callback.get());

  }

  if (options.update_state_every_iteration) {

    pp->state_updating_callback.reset(

      new StateUpdatingCallback(program, reduced_parameters));

    // This must get pushed to the front of the callbacks so that it

    // is run before any of the user callbacks.

    minimizer_options.callbacks.insert(minimizer_options.callbacks.begin(),

                                       pp->state_updating_callback.get());

  }

}

}  // namespace internal

}  // namespace ceres