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

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

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

#include "ceres/cost_function_to_functor.h"

#include "ceres/dynamic_autodiff_cost_function.h"

#include "ceres/dynamic_cost_function_to_functor.h"

#include "ceres/autodiff_cost_function.h"

#include "gtest/gtest.h"

namespace ceres {

namespace internal {

using std::vector;

const double kTolerance = 1e-18;

void ExpectCostFunctionsAreEqual(const CostFunction& cost_function,

                                 const CostFunction& actual_cost_function) {

  EXPECT_EQ(cost_function.num_residuals(),

            actual_cost_function.num_residuals());

  const int num_residuals = cost_function.num_residuals();

  const vector<int32>& parameter_block_sizes =

      cost_function.parameter_block_sizes();

  const vector<int32>& actual_parameter_block_sizes =

      actual_cost_function.parameter_block_sizes();

  EXPECT_EQ(parameter_block_sizes.size(),

            actual_parameter_block_sizes.size());

  int num_parameters = 0;

  for (int i = 0; i < parameter_block_sizes.size(); ++i) {

    EXPECT_EQ(parameter_block_sizes[i], actual_parameter_block_sizes[i]);

    num_parameters += parameter_block_sizes[i];

  }

  scoped_array<double> parameters(new double[num_parameters]);

  for (int i = 0; i < num_parameters; ++i) {

    parameters[i] = static_cast<double>(i) + 1.0;

  }

  scoped_array<double> residuals(new double[num_residuals]);

  scoped_array<double> jacobians(new double[num_parameters * num_residuals]);

  scoped_array<double> actual_residuals(new double[num_residuals]);

  scoped_array<double> actual_jacobians

      (new double[num_parameters * num_residuals]);

  scoped_array<double*> parameter_blocks(

      new double*[parameter_block_sizes.size()]);

  scoped_array<double*> jacobian_blocks(

      new double*[parameter_block_sizes.size()]);

  scoped_array<double*> actual_jacobian_blocks(

      new double*[parameter_block_sizes.size()]);

  num_parameters = 0;

  for (int i = 0; i < parameter_block_sizes.size(); ++i) {

    parameter_blocks[i] = parameters.get() + num_parameters;

    jacobian_blocks[i] = jacobians.get() + num_parameters * num_residuals;

    actual_jacobian_blocks[i] =

        actual_jacobians.get() + num_parameters * num_residuals;

    num_parameters += parameter_block_sizes[i];

  }

  EXPECT_TRUE(cost_function.Evaluate(parameter_blocks.get(),

                                     residuals.get(), NULL));

  EXPECT_TRUE(actual_cost_function.Evaluate(parameter_blocks.get(),

                                            actual_residuals.get(), NULL));

  for (int i = 0; i < num_residuals; ++i) {

    EXPECT_NEAR(residuals[i], actual_residuals[i], kTolerance)

        << "residual id: " << i;

  }

  EXPECT_TRUE(cost_function.Evaluate(parameter_blocks.get(),

                                     residuals.get(),

                                     jacobian_blocks.get()));

  EXPECT_TRUE(actual_cost_function.Evaluate(parameter_blocks.get(),

                                            actual_residuals.get(),

                                            actual_jacobian_blocks.get()));

  for (int i = 0; i < num_residuals; ++i) {

    EXPECT_NEAR(residuals[i], actual_residuals[i], kTolerance)

        << "residual : " << i;

  }

  for (int i = 0; i < num_residuals * num_parameters; ++i) {

    EXPECT_NEAR(jacobians[i], actual_jacobians[i], kTolerance)

        << "jacobian : " << i << " "

        << jacobians[i] << " " << actual_jacobians[i];

  }

}

struct OneParameterBlockFunctor {

 public:

  template <typename T>

  bool operator()(const T* x1, T* residuals) const {

    residuals[0] = x1[0] * x1[0];

    residuals[1] = x1[1] * x1[1];

    return true;

  }

};

struct TwoParameterBlockFunctor {

 public:

  template <typename T>

  bool operator()(const T* x1, const T* x2, T* residuals) const {

    residuals[0] = x1[0] * x1[0]  + x2[0] * x2[0];

    residuals[1] = x1[1] * x1[1]  + x2[1] * x2[1];

    return true;

  }

};

struct ThreeParameterBlockFunctor {

 public:

  template <typename T>

  bool operator()(const T* x1, const T* x2, const T* x3, T* residuals) const {

    residuals[0] = x1[0] * x1[0]  + x2[0] * x2[0] + x3[0] * x3[0];

    residuals[1] = x1[1] * x1[1]  + x2[1] * x2[1] + x3[1] * x3[1];

    return true;

  }

};

struct FourParameterBlockFunctor {

 public:

  template <typename T>

  bool operator()(const T* x1, const T* x2, const T* x3, const T* x4,

                  T* residuals) const {

    residuals[0] = x1[0] * x1[0]  + x2[0] * x2[0] + x3[0] * x3[0]

        + x4[0] * x4[0];

    residuals[1] = x1[1] * x1[1]  + x2[1] * x2[1] + x3[1] * x3[1]

        + x4[1] * x4[1];

    return true;

  }

};

struct FiveParameterBlockFunctor {

 public:

  template <typename T>

  bool operator()(const T* x1, const T* x2, const T* x3, const T* x4,

                  const T* x5, T* residuals) const {

    residuals[0] = x1[0] * x1[0]  + x2[0] * x2[0] + x3[0] * x3[0]

        + x4[0] * x4[0] + x5[0] * x5[0];

    residuals[1] = x1[1] * x1[1]  + x2[1] * x2[1] + x3[1] * x3[1]

        + x4[1] * x4[1] + x5[1] * x5[1];

    return true;

  }

};

struct SixParameterBlockFunctor {

 public:

  template <typename T>

  bool operator()(const T* x1, const T* x2, const T* x3, const T* x4,

                  const T* x5, const T* x6,  T* residuals) const {

    residuals[0] = x1[0] * x1[0]  + x2[0] * x2[0] + x3[0] * x3[0]

        + x4[0] * x4[0] + x5[0] * x5[0] + x6[0] * x6[0];

    residuals[1] = x1[1] * x1[1]  + x2[1] * x2[1] + x3[1] * x3[1]

        + x4[1] * x4[1] + x5[1] * x5[1] + x6[1] * x6[1];

    return true;

  }

};

struct SevenParameterBlockFunctor {

 public:

  template <typename T>

  bool operator()(const T* x1, const T* x2, const T* x3, const T* x4,

                  const T* x5, const T* x6, const T* x7, T* residuals) const {

    residuals[0] = x1[0] * x1[0]  + x2[0] * x2[0] + x3[0] * x3[0]

        + x4[0] * x4[0] + x5[0] * x5[0] + x6[0] * x6[0] + x7[0] * x7[0];

    residuals[1] = x1[1] * x1[1]  + x2[1] * x2[1] + x3[1] * x3[1]

        + x4[1] * x4[1] + x5[1] * x5[1] + x6[1] * x6[1] + x7[1] * x7[1];

    return true;

  }

};

struct EightParameterBlockFunctor {

 public:

  template <typename T>

  bool operator()(const T* x1, const T* x2, const T* x3, const T* x4,

                  const T* x5, const T* x6, const T* x7, const T* x8,

                  T* residuals) const {

    residuals[0] = x1[0] * x1[0]  + x2[0] * x2[0] + x3[0] * x3[0]

        + x4[0] * x4[0] + x5[0] * x5[0] + x6[0] * x6[0] + x7[0] * x7[0]

        + x8[0] * x8[0];

    residuals[1] = x1[1] * x1[1]  + x2[1] * x2[1] + x3[1] * x3[1]

        + x4[1] * x4[1] + x5[1] * x5[1] + x6[1] * x6[1] + x7[1] * x7[1]

        + x8[1] * x8[1];

    return true;

  }

};

struct NineParameterBlockFunctor {

 public:

  template <typename T>

  bool operator()(const T* x1, const T* x2, const T* x3, const T* x4,

                  const T* x5, const T* x6, const T* x7, const T* x8,

                  const T* x9, T* residuals) const {

    residuals[0] = x1[0] * x1[0]  + x2[0] * x2[0] + x3[0] * x3[0]

        + x4[0] * x4[0] + x5[0] * x5[0] + x6[0] * x6[0] + x7[0] * x7[0]

        + x8[0] * x8[0] + x9[0] * x9[0];

    residuals[1] = x1[1] * x1[1]  + x2[1] * x2[1] + x3[1] * x3[1]

        + x4[1] * x4[1] + x5[1] * x5[1] + x6[1] * x6[1] + x7[1] * x7[1]

        + x8[1] * x8[1] + x9[1] * x9[1];

    return true;

  }

};

struct TenParameterBlockFunctor {

 public:

  template <typename T>

  bool operator()(const T* x1, const T* x2, const T* x3, const T* x4,

                  const T* x5, const T* x6, const T* x7, const T* x8,

                  const T* x9, const T* x10, T* residuals) const {

    residuals[0] = x1[0] * x1[0]  + x2[0] * x2[0] + x3[0] * x3[0]

        + x4[0] * x4[0] + x5[0] * x5[0] + x6[0] * x6[0] + x7[0] * x7[0]

        + x8[0] * x8[0] + x9[0] * x9[0] + x10[0] * x10[0];

    residuals[1] = x1[1] * x1[1]  + x2[1] * x2[1] + x3[1] * x3[1]

        + x4[1] * x4[1] + x5[1] * x5[1] + x6[1] * x6[1] + x7[1] * x7[1]

        + x8[1] * x8[1] + x9[1] * x9[1] + x10[1] * x10[1];

    return true;

  }

};

class DynamicTwoParameterBlockFunctor {

 public:

  template <typename T>

  bool operator()(T const* const* parameters, T* residuals) const {

    for (int i = 0; i < 2; ++i) {

      residuals[0] = parameters[i][0] * parameters[i][0];

      residuals[1] = parameters[i][1] * parameters[i][1];

    }

    return true;

  }

};

#define TEST_BODY(NAME)                                                 \

  TEST(CostFunctionToFunctor, NAME) {                                   \

    scoped_ptr<CostFunction> cost_function(                             \

        new AutoDiffCostFunction<                                       \

            CostFunctionToFunctor<2, PARAMETER_BLOCK_SIZES >,           \

                2, PARAMETER_BLOCK_SIZES>(new CostFunctionToFunctor<    \

                    2, PARAMETER_BLOCK_SIZES >(                         \

                        new AutoDiffCostFunction<                       \

                            NAME##Functor, 2, PARAMETER_BLOCK_SIZES >(  \

                  new NAME##Functor))));                                \

                                                                        \

scoped_ptr<CostFunction> actual_cost_function(                          \

    new AutoDiffCostFunction<NAME##Functor, 2, PARAMETER_BLOCK_SIZES >( \

        new NAME##Functor));                                            \

ExpectCostFunctionsAreEqual(*cost_function, *actual_cost_function);     \

}

#define PARAMETER_BLOCK_SIZES 2

TEST_BODY(OneParameterBlock)

#undef PARAMETER_BLOCK_SIZES

#define PARAMETER_BLOCK_SIZES 2,2

TEST_BODY(TwoParameterBlock)

#undef PARAMETER_BLOCK_SIZES

#define PARAMETER_BLOCK_SIZES 2,2,2

TEST_BODY(ThreeParameterBlock)

#undef PARAMETER_BLOCK_SIZES

#define PARAMETER_BLOCK_SIZES 2,2,2,2

TEST_BODY(FourParameterBlock)

#undef PARAMETER_BLOCK_SIZES

#define PARAMETER_BLOCK_SIZES 2,2,2,2,2

TEST_BODY(FiveParameterBlock)

#undef PARAMETER_BLOCK_SIZES

#define PARAMETER_BLOCK_SIZES 2,2,2,2,2,2

TEST_BODY(SixParameterBlock)

#undef PARAMETER_BLOCK_SIZES

#define PARAMETER_BLOCK_SIZES 2,2,2,2,2,2,2

TEST_BODY(SevenParameterBlock)

#undef PARAMETER_BLOCK_SIZES

#define PARAMETER_BLOCK_SIZES 2,2,2,2,2,2,2,2

TEST_BODY(EightParameterBlock)

#undef PARAMETER_BLOCK_SIZES

#define PARAMETER_BLOCK_SIZES 2,2,2,2,2,2,2,2,2

TEST_BODY(NineParameterBlock)

#undef PARAMETER_BLOCK_SIZES

#define PARAMETER_BLOCK_SIZES 2,2,2,2,2,2,2,2,2,2

TEST_BODY(TenParameterBlock)

#undef PARAMETER_BLOCK_SIZES

#undef TEST_BODY

TEST(CostFunctionToFunctor, DynamicNumberOfResiduals) {

  scoped_ptr<CostFunction> cost_function(

      new AutoDiffCostFunction<

      CostFunctionToFunctor<ceres::DYNAMIC, 2, 2 >, ceres::DYNAMIC, 2, 2>(

          new CostFunctionToFunctor<ceres::DYNAMIC, 2, 2 >(

              new AutoDiffCostFunction<TwoParameterBlockFunctor, 2, 2, 2 >(

                  new TwoParameterBlockFunctor)), 2));

  scoped_ptr<CostFunction> actual_cost_function(

      new AutoDiffCostFunction<TwoParameterBlockFunctor, 2, 2, 2 >(

          new TwoParameterBlockFunctor));

  ExpectCostFunctionsAreEqual(*cost_function, *actual_cost_function);

}

TEST(CostFunctionToFunctor, DynamicCostFunctionToFunctor) {

  DynamicAutoDiffCostFunction<DynamicTwoParameterBlockFunctor>*

      actual_cost_function(

      new DynamicAutoDiffCostFunction<DynamicTwoParameterBlockFunctor>(

          new DynamicTwoParameterBlockFunctor));

  actual_cost_function->AddParameterBlock(2);

  actual_cost_function->AddParameterBlock(2);

  actual_cost_function->SetNumResiduals(2);

  DynamicAutoDiffCostFunction<DynamicCostFunctionToFunctor> cost_function(

      new DynamicCostFunctionToFunctor(actual_cost_function));

  cost_function.AddParameterBlock(2);

  cost_function.AddParameterBlock(2);

  cost_function.SetNumResiduals(2);

  ExpectCostFunctionsAreEqual(cost_function, *actual_cost_function);

}

}  // namespace internal

}  // namespace ceres