// Ceres Solver - A fast non-linear least squares minimizer
// Copyright 2023 Google Inc. All rights reserved.
// http://ceres-solver.org/
//
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// modification, are permitted provided that the following conditions are met:
//
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//   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.
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//   used to endorse or promote products derived from this software without
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//
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// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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// Author: sameeragarwal@google.com (Sameer Agarwal)

#include "ceres/minimizer.h"

#include <memory>

#include "absl/log/log.h"
#include "ceres/line_search_minimizer.h"
#include "ceres/trust_region_minimizer.h"
#include "ceres/types.h"

namespace ceres::internal {

std::unique_ptr<Minimizer> Minimizer::Create(MinimizerType minimizer_type) {
  if (minimizer_type == TRUST_REGION) {
    return std::make_unique<TrustRegionMinimizer>();
  }

  if (minimizer_type == LINE_SEARCH) {
    return std::make_unique<LineSearchMinimizer>();
  }

  LOG(FATAL) << "Unknown minimizer_type: " << minimizer_type;
  return nullptr;
}

Minimizer::~Minimizer() = default;

bool Minimizer::RunCallbacks(const Minimizer::Options& options,
                             const IterationSummary& iteration_summary,
                             Solver::Summary* summary) {
  const bool is_not_silent = !options.is_silent;
  CallbackReturnType status = SOLVER_CONTINUE;
  int i = 0;
  while (status == SOLVER_CONTINUE && i < options.callbacks.size()) {
    status = (*options.callbacks[i])(iteration_summary);
    ++i;
  }
  switch (status) {
    case SOLVER_CONTINUE:
      return true;
    case SOLVER_TERMINATE_SUCCESSFULLY:
      summary->termination_type = USER_SUCCESS;
      summary->message =
          "User callback returned SOLVER_TERMINATE_SUCCESSFULLY.";
      if (is_not_silent) {
        VLOG(1) << "Terminating: " << summary->message;
      }
      return false;
    case SOLVER_ABORT:
      summary->termination_type = USER_FAILURE;
      summary->message = "User callback returned SOLVER_ABORT.";
      if (is_not_silent) {
        VLOG(1) << "Terminating: " << summary->message;
      }
      return false;
    default:
      LOG(FATAL) << "Unknown type of user callback status";
  }
  return false;
}

}  // namespace ceres::internal