// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2013 Gael Guennebaud <gael.guennebaud@inria.fr>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
// SPDX-License-Identifier: MPL-2.0

// This unit test cannot be easily written to work with EIGEN_DEFAULT_TO_ROW_MAJOR
#ifdef EIGEN_DEFAULT_TO_ROW_MAJOR
#undef EIGEN_DEFAULT_TO_ROW_MAJOR
#endif

#define TEST_ENABLE_TEMPORARY_TRACKING
#define TEST_CHECK_STATIC_ASSERTIONS
#include "main.h"

// test Ref.h

// Deal with i387 extended precision
#if EIGEN_ARCH_i386 && !(EIGEN_ARCH_x86_64)

#if EIGEN_COMP_GNUC_STRICT
#pragma GCC optimize("-ffloat-store")
#else
#undef VERIFY_IS_EQUAL
#define VERIFY_IS_EQUAL(X, Y) VERIFY_IS_APPROX(X, Y)
#endif

#endif

template <typename MatrixType>
void ref_matrix(const MatrixType &m) {
  typedef typename MatrixType::Scalar Scalar;
  typedef typename MatrixType::RealScalar RealScalar;
  typedef Matrix<Scalar, Dynamic, Dynamic, MatrixType::Options> DynMatrixType;
  typedef Matrix<RealScalar, Dynamic, Dynamic, MatrixType::Options> RealDynMatrixType;

  typedef Ref<MatrixType> RefMat;
  typedef Ref<DynMatrixType> RefDynMat;
  typedef Ref<const DynMatrixType> ConstRefDynMat;
  typedef Ref<RealDynMatrixType, 0, Stride<Dynamic, Dynamic>> RefRealMatWithStride;

  Index rows = m.rows(), cols = m.cols();

  MatrixType m1 = MatrixType::Random(rows, cols), m2 = m1;

  Index i = internal::random<Index>(0, rows - 1);
  Index j = internal::random<Index>(0, cols - 1);
  Index brows = internal::random<Index>(1, rows - i);
  Index bcols = internal::random<Index>(1, cols - j);

  RefMat rm0 = m1;
  VERIFY_IS_EQUAL(rm0, m1);
  RefDynMat rm1 = m1;
  VERIFY_IS_EQUAL(rm1, m1);
  RefDynMat rm2 = m1.block(i, j, brows, bcols);
  VERIFY_IS_EQUAL(rm2, m1.block(i, j, brows, bcols));
  rm2.setOnes();
  m2.block(i, j, brows, bcols).setOnes();
  VERIFY_IS_EQUAL(m1, m2);

  m2.block(i, j, brows, bcols).setRandom();
  rm2 = m2.block(i, j, brows, bcols);
  VERIFY_IS_EQUAL(m1, m2);

  ConstRefDynMat rm3 = m1.block(i, j, brows, bcols);
  m1.block(i, j, brows, bcols) *= 2;
  m2.block(i, j, brows, bcols) *= 2;
  VERIFY_IS_EQUAL(rm3, m2.block(i, j, brows, bcols));
  RefRealMatWithStride rm4 = m1.real();
  VERIFY_IS_EQUAL(rm4, m2.real());
  rm4.array() += 1;
  m2.real().array() += 1;
  VERIFY_IS_EQUAL(m1, m2);
}

template <typename VectorType>
void ref_vector(const VectorType &m) {
  typedef typename VectorType::Scalar Scalar;
  typedef typename VectorType::RealScalar RealScalar;
  typedef Matrix<Scalar, Dynamic, 1, VectorType::Options> DynMatrixType;
  typedef Matrix<Scalar, Dynamic, Dynamic, ColMajor> MatrixType;
  typedef Matrix<RealScalar, Dynamic, 1, VectorType::Options> RealDynMatrixType;

  typedef Ref<VectorType> RefMat;
  typedef Ref<DynMatrixType> RefDynMat;
  typedef Ref<const DynMatrixType> ConstRefDynMat;
  typedef Ref<RealDynMatrixType, 0, InnerStride<>> RefRealMatWithStride;
  typedef Ref<DynMatrixType, 0, InnerStride<>> RefMatWithStride;

  Index size = m.size();

  VectorType v1 = VectorType::Random(size), v2 = v1;
  MatrixType mat1 = MatrixType::Random(size, size), mat2 = mat1, mat3 = MatrixType::Random(size, size);

  Index i = internal::random<Index>(0, size - 1);
  Index bsize = internal::random<Index>(1, size - i);

  {
    RefMat rm0 = v1;
    VERIFY_IS_EQUAL(rm0, v1);
  }
  {
    RefMat rm0 = v1.block(0, 0, size, 1);
    VERIFY_IS_EQUAL(rm0, v1);
  }
  {
    RefDynMat rv1 = v1;
    VERIFY_IS_EQUAL(rv1, v1);
  }
  {
    RefDynMat rv1 = v1.block(0, 0, size, 1);
    VERIFY_IS_EQUAL(rv1, v1);
  }

  RefDynMat rv2 = v1.segment(i, bsize);
  VERIFY_IS_EQUAL(rv2, v1.segment(i, bsize));
  rv2.setOnes();
  v2.segment(i, bsize).setOnes();
  VERIFY_IS_EQUAL(v1, v2);

  v2.segment(i, bsize).setRandom();
  rv2 = v2.segment(i, bsize);
  VERIFY_IS_EQUAL(v1, v2);

  ConstRefDynMat rm3 = v1.segment(i, bsize);
  v1.segment(i, bsize) *= 2;
  v2.segment(i, bsize) *= 2;
  VERIFY_IS_EQUAL(rm3, v2.segment(i, bsize));

  RefRealMatWithStride rm4 = v1.real();
  VERIFY_IS_EQUAL(rm4, v2.real());
  rm4.array() += 1;
  v2.real().array() += 1;
  VERIFY_IS_EQUAL(v1, v2);

  RefMatWithStride rm5 = mat1.row(i).transpose();
  VERIFY_IS_EQUAL(rm5, mat1.row(i).transpose());
  rm5.array() += 1;
  mat2.row(i).array() += 1;
  VERIFY_IS_EQUAL(mat1, mat2);
  rm5.noalias() = rm4.transpose() * mat3;
  mat2.row(i) = v2.real().transpose() * mat3;
  VERIFY_IS_APPROX(mat1, mat2);
}

template <typename Scalar, int Rows, int Cols>
void ref_vector_fixed_sizes() {
  typedef Matrix<Scalar, Rows, Cols, RowMajor> RowMajorMatrixType;
  typedef Matrix<Scalar, Rows, Cols, ColMajor> ColMajorMatrixType;
  typedef Matrix<Scalar, 1, Cols> RowVectorType;
  typedef Matrix<Scalar, Rows, 1> ColVectorType;
  typedef Matrix<Scalar, Cols, 1> RowVectorTransposeType;
  typedef Matrix<Scalar, 1, Rows> ColVectorTransposeType;
  typedef Stride<Dynamic, Dynamic> DynamicStride;

  RowMajorMatrixType mr = RowMajorMatrixType::Random();
  ColMajorMatrixType mc = ColMajorMatrixType::Random();

  Index i = internal::random<Index>(0, Rows - 1);
  Index j = internal::random<Index>(0, Cols - 1);

  // Reference ith row.
  Ref<RowVectorType, 0, DynamicStride> mr_ri = mr.row(i);
  VERIFY_IS_EQUAL(mr_ri, mr.row(i));
  Ref<RowVectorType, 0, DynamicStride> mc_ri = mc.row(i);
  VERIFY_IS_EQUAL(mc_ri, mc.row(i));

  // Reference jth col.
  Ref<ColVectorType, 0, DynamicStride> mr_cj = mr.col(j);
  VERIFY_IS_EQUAL(mr_cj, mr.col(j));
  Ref<ColVectorType, 0, DynamicStride> mc_cj = mc.col(j);
  VERIFY_IS_EQUAL(mc_cj, mc.col(j));

  // Reference the transpose of row i.
  Ref<RowVectorTransposeType, 0, DynamicStride> mr_rit = mr.row(i);
  VERIFY_IS_EQUAL(mr_rit, mr.row(i).transpose());
  Ref<RowVectorTransposeType, 0, DynamicStride> mc_rit = mc.row(i);
  VERIFY_IS_EQUAL(mc_rit, mc.row(i).transpose());

  // Reference the transpose of col j.
  Ref<ColVectorTransposeType, 0, DynamicStride> mr_cjt = mr.col(j);
  VERIFY_IS_EQUAL(mr_cjt, mr.col(j).transpose());
  Ref<ColVectorTransposeType, 0, DynamicStride> mc_cjt = mc.col(j);
  VERIFY_IS_EQUAL(mc_cjt, mc.col(j).transpose());

  // Const references without strides.
  Ref<const RowVectorType> cmr_ri = mr.row(i);
  VERIFY_IS_EQUAL(cmr_ri, mr.row(i));
  Ref<const RowVectorType> cmc_ri = mc.row(i);
  VERIFY_IS_EQUAL(cmc_ri, mc.row(i));

  Ref<const ColVectorType> cmr_cj = mr.col(j);
  VERIFY_IS_EQUAL(cmr_cj, mr.col(j));
  Ref<const ColVectorType> cmc_cj = mc.col(j);
  VERIFY_IS_EQUAL(cmc_cj, mc.col(j));

  Ref<const RowVectorTransposeType> cmr_rit = mr.row(i);
  VERIFY_IS_EQUAL(cmr_rit, mr.row(i).transpose());
  Ref<const RowVectorTransposeType> cmc_rit = mc.row(i);
  VERIFY_IS_EQUAL(cmc_rit, mc.row(i).transpose());

  Ref<const ColVectorTransposeType> cmr_cjt = mr.col(j);
  VERIFY_IS_EQUAL(cmr_cjt, mr.col(j).transpose());
  Ref<const ColVectorTransposeType> cmc_cjt = mc.col(j);
  VERIFY_IS_EQUAL(cmc_cjt, mc.col(j).transpose());
}

template <typename PlainObjectType>
void check_const_correctness(const PlainObjectType &) {
  // verify that ref-to-const don't have LvalueBit
  typedef std::add_const_t<PlainObjectType> ConstPlainObjectType;
  VERIFY(!(internal::traits<Ref<ConstPlainObjectType>>::Flags & LvalueBit));
  VERIFY(!(internal::traits<Ref<ConstPlainObjectType, Aligned>>::Flags & LvalueBit));
  VERIFY(!(Ref<ConstPlainObjectType>::Flags & LvalueBit));
  VERIFY(!(Ref<ConstPlainObjectType, Aligned>::Flags & LvalueBit));
}

void test_ref_alignment_matching() {
  using PlainObject = Matrix<float, Dynamic, 1, DontAlign>;
  using UnalignedMap = Map<PlainObject, Unaligned>;
  using Aligned8Map = Map<PlainObject, Aligned8>;
  using Aligned16Map = Map<PlainObject, Aligned16>;
  using Aligned32Map = Map<PlainObject, Aligned32>;
  using UnalignedRefTraits = internal::traits<Ref<PlainObject, Unaligned>>;
  using Aligned16RefTraits = internal::traits<Ref<PlainObject, Aligned16>>;

  static_assert(int(internal::traits<PlainObject>::Alignment) == int(Unaligned),
                "the test plain object must not provide an alignment guarantee");
  static_assert(UnalignedRefTraits::template match<UnalignedMap>::AlignmentMatch,
                "an unaligned Ref must accept an unaligned source");
  static_assert(!Aligned16RefTraits::template match<UnalignedMap>::AlignmentMatch,
                "an aligned Ref must reject a source without an alignment guarantee");
  static_assert(!Aligned16RefTraits::template match<Aligned8Map>::AlignmentMatch,
                "the source alignment must satisfy the Ref alignment");
  static_assert(Aligned16RefTraits::template match<Aligned16Map>::AlignmentMatch,
                "a Ref must accept a source with matching alignment");
  static_assert(Aligned16RefTraits::template match<Aligned32Map>::AlignmentMatch,
                "a Ref must accept a source with stronger alignment");

  alignas(16) float data[8] = {};
  Aligned16Map map(data, 8);
  Ref<PlainObject, Aligned16> ref(map);
  VERIFY(ref.data() == data);
}

template <typename B>
EIGEN_DONT_INLINE void call_ref_1(Ref<VectorXf> a, const B &b) {
  VERIFY_IS_EQUAL(a, b);
}
template <typename B>
EIGEN_DONT_INLINE void call_ref_2(const Ref<const VectorXf> &a, const B &b) {
  VERIFY_IS_EQUAL(a, b);
}
template <typename B>
EIGEN_DONT_INLINE void call_ref_3(Ref<VectorXf, 0, InnerStride<>> a, const B &b) {
  VERIFY_IS_EQUAL(a, b);
}
template <typename B>
EIGEN_DONT_INLINE void call_ref_4(const Ref<const VectorXf, 0, InnerStride<>> &a, const B &b) {
  VERIFY_IS_EQUAL(a, b);
}
template <typename B>
EIGEN_DONT_INLINE void call_ref_5(Ref<MatrixXf, 0, OuterStride<>> a, const B &b) {
  VERIFY_IS_EQUAL(a, b);
}
template <typename B>
EIGEN_DONT_INLINE void call_ref_6(const Ref<const MatrixXf, 0, OuterStride<>> &a, const B &b) {
  VERIFY_IS_EQUAL(a, b);
}
template <typename B>
EIGEN_DONT_INLINE void call_ref_7(Ref<Matrix<float, Dynamic, 3>> a, const B &b) {
  VERIFY_IS_EQUAL(a, b);
}

void call_ref() {
  VectorXcf ca = VectorXcf::Random(10);
  VectorXf a = VectorXf::Random(10);
  RowVectorXf b = RowVectorXf::Random(10);
  MatrixXf A = MatrixXf::Random(10, 10);
  RowVector3f c = RowVector3f::Random();
  const VectorXf &ac(a);
  VectorBlock<VectorXf> ab(a, 0, 3);
  const VectorBlock<VectorXf> abc(a, 0, 3);

  VERIFY_EVALUATION_COUNT(call_ref_1(a, a), 0);
  VERIFY_EVALUATION_COUNT(call_ref_1(b, b.transpose()), 0);
  //   call_ref_1(ac,a<c);           // does not compile because ac is const
  VERIFY_EVALUATION_COUNT(call_ref_1(ab, ab), 0);
  VERIFY_EVALUATION_COUNT(call_ref_1(a.head(4), a.head(4)), 0);
  VERIFY_EVALUATION_COUNT(call_ref_1(abc, abc), 0);
  VERIFY_EVALUATION_COUNT(call_ref_1(A.col(3), A.col(3)), 0);
  //   call_ref_1(A.row(3),A.row(3));    // does not compile because innerstride!=1
  VERIFY_EVALUATION_COUNT(call_ref_3(A.row(3), A.row(3).transpose()), 0);
  VERIFY_EVALUATION_COUNT(call_ref_4(A.row(3), A.row(3).transpose()), 0);
  //   call_ref_1(a+a, a+a);          // does not compile for obvious reason

  MatrixXf tmp = A * A.col(1);
  VERIFY_EVALUATION_COUNT(call_ref_2(A * A.col(1), tmp), 1);  // evaluated into a temp
  VERIFY_EVALUATION_COUNT(call_ref_2(ac.head(5), ac.head(5)), 0);
  VERIFY_EVALUATION_COUNT(call_ref_2(ac, ac), 0);
  VERIFY_EVALUATION_COUNT(call_ref_2(a, a), 0);
  VERIFY_EVALUATION_COUNT(call_ref_2(ab, ab), 0);
  VERIFY_EVALUATION_COUNT(call_ref_2(a.head(4), a.head(4)), 0);
  tmp = a + a;
  VERIFY_EVALUATION_COUNT(call_ref_2(a + a, tmp), 1);            // evaluated into a temp
  VERIFY_EVALUATION_COUNT(call_ref_2(ca.imag(), ca.imag()), 1);  // evaluated into a temp

  VERIFY_EVALUATION_COUNT(call_ref_4(ac.head(5), ac.head(5)), 0);
  tmp = a + a;
  VERIFY_EVALUATION_COUNT(call_ref_4(a + a, tmp), 1);  // evaluated into a temp
  VERIFY_EVALUATION_COUNT(call_ref_4(ca.imag(), ca.imag()), 0);

  VERIFY_EVALUATION_COUNT(call_ref_5(a, a), 0);
  VERIFY_EVALUATION_COUNT(call_ref_5(a.head(3), a.head(3)), 0);
  VERIFY_EVALUATION_COUNT(call_ref_5(A, A), 0);
  //   call_ref_5(A.transpose(),A.transpose());   // does not compile because storage order does not match
  VERIFY_EVALUATION_COUNT(call_ref_5(A.block(1, 1, 2, 2), A.block(1, 1, 2, 2)), 0);
  VERIFY_EVALUATION_COUNT(call_ref_5(b, b),
                          0);  // storage order do not match, but this is a degenerate case that should work
  VERIFY_EVALUATION_COUNT(call_ref_5(a.row(3), a.row(3)), 0);

  VERIFY_EVALUATION_COUNT(call_ref_6(a, a), 0);
  VERIFY_EVALUATION_COUNT(call_ref_6(a.head(3), a.head(3)), 0);
  VERIFY_EVALUATION_COUNT(call_ref_6(A.row(3), A.row(3)),
                          1);  // evaluated into a temp thouth it could be avoided by viewing it as a 1xn matrix
  tmp = A + A;
  VERIFY_EVALUATION_COUNT(call_ref_6(A + A, tmp), 1);  // evaluated into a temp
  VERIFY_EVALUATION_COUNT(call_ref_6(A, A), 0);
  VERIFY_EVALUATION_COUNT(call_ref_6(A.transpose(), A.transpose()),
                          1);  // evaluated into a temp because the storage orders do not match
  VERIFY_EVALUATION_COUNT(call_ref_6(A.block(1, 1, 2, 2), A.block(1, 1, 2, 2)), 0);

  VERIFY_EVALUATION_COUNT(call_ref_7(c, c), 0);
}

typedef Matrix<double, Dynamic, Dynamic, RowMajor> RowMatrixXd;
int test_ref_overload_fun1(Ref<MatrixXd>) { return 1; }
int test_ref_overload_fun1(Ref<RowMatrixXd>) { return 2; }
int test_ref_overload_fun1(Ref<MatrixXf>) { return 3; }

int test_ref_overload_fun2(Ref<const MatrixXd>) { return 4; }
int test_ref_overload_fun2(Ref<const MatrixXf>) { return 5; }

void test_ref_ambiguous(const Ref<const ArrayXd> &A, Ref<ArrayXd> B) {
  B = A;
  B = A - A;
}

// See also bug 969
void test_ref_overloads() {
  MatrixXd Ad, Bd;
  RowMatrixXd rAd, rBd;
  VERIFY(test_ref_overload_fun1(Ad) == 1);
  VERIFY(test_ref_overload_fun1(rAd) == 2);

  MatrixXf Af, Bf;
  VERIFY(test_ref_overload_fun2(Ad) == 4);
  VERIFY(test_ref_overload_fun2(Ad + Bd) == 4);
  VERIFY(test_ref_overload_fun2(Af + Bf) == 5);

  ArrayXd A, B;
  test_ref_ambiguous(A, B);
}

template <typename Ref_>
struct RefDerived : Ref_ {
  using Ref_::m_object;
};

template <typename MatrixType, typename Derived>
void test_cref_move_ctor(const DenseBase<Derived> &expr) {
  typedef Ref<const MatrixType> CRef;
  typedef RefDerived<CRef> CRefDerived;

  const bool owns_data = !bool(internal::traits<CRef>::template match<Derived>::type::value);
  CRef cref1(expr);
  const double *data1 = cref1.data(), *obj_data1 = static_cast<CRefDerived &>(cref1).m_object.data();
  VERIFY(test_is_equal(data1, obj_data1, owns_data));
  CRef cref2(std::move(cref1));
  VERIFY_IS_EQUAL(std::uintptr_t(data1), std::uintptr_t(cref1.data()));
  const double *data2 = cref2.data(), *obj_data2 = static_cast<CRefDerived &>(cref2).m_object.data();
  VERIFY(test_is_equal(data1, data2, MatrixType::MaxSizeAtCompileTime == Dynamic || !owns_data));
  VERIFY(test_is_equal(data1, obj_data2, MatrixType::MaxSizeAtCompileTime == Dynamic && owns_data));
}

template <typename MatrixType>
void test_contiguous_ref_no_copy(const PlainObjectBase<MatrixType> &obj) {
  typedef Ref<MatrixType, Unaligned, Stride<0, 0>> Ref_;
  typedef Ref<const MatrixType, Unaligned, Stride<0, 0>> CRef_;
  MatrixType m(obj);
  Ref_ ref(m);
  VERIFY(test_is_equal(ref.data(), m.data(), true));
  CRef_ cref(m);
  VERIFY(test_is_equal(cref.data(), m.data(), true));
}

EIGEN_DECLARE_TEST(ref) {
  for (int i = 0; i < g_repeat; i++) {
    CALL_SUBTEST_1(ref_vector(Matrix<float, 1, 1>()));
    CALL_SUBTEST_1(check_const_correctness(Matrix<float, 1, 1>()));
    CALL_SUBTEST_2(ref_vector(Vector4d()));
    CALL_SUBTEST_2(check_const_correctness(Matrix4d()));
    CALL_SUBTEST_3(ref_vector(Vector4cf()));
    CALL_SUBTEST_4(ref_vector(VectorXcf(8)));
    CALL_SUBTEST_5(ref_vector(VectorXi(12)));
    CALL_SUBTEST_5(check_const_correctness(VectorXi(12)));

    CALL_SUBTEST_1(ref_matrix(Matrix<float, 1, 1>()));
    CALL_SUBTEST_2(ref_matrix(Matrix4d()));
    CALL_SUBTEST_1(ref_matrix(Matrix<float, 3, 5>()));
    CALL_SUBTEST_4(ref_matrix(MatrixXcf(internal::random<int>(1, 10), internal::random<int>(1, 10))));
    CALL_SUBTEST_4(ref_matrix(Matrix<std::complex<double>, 10, 15>()));
    CALL_SUBTEST_5(ref_matrix(MatrixXi(internal::random<int>(1, 10), internal::random<int>(1, 10))));
    CALL_SUBTEST_6(call_ref());

    CALL_SUBTEST_8((ref_vector_fixed_sizes<float, 3, 5>()));
    CALL_SUBTEST_8((ref_vector_fixed_sizes<float, 15, 10>()));
  }

  CALL_SUBTEST_7(test_ref_overloads());

  CALL_SUBTEST_9(test_cref_move_ctor<VectorXd>(VectorXd::Ones(9)));
  CALL_SUBTEST_9(test_cref_move_ctor<VectorXd>(VectorXd(9)));
  CALL_SUBTEST_9(test_cref_move_ctor<Vector3d>(Vector3d::Ones()));
  CALL_SUBTEST_9(test_cref_move_ctor<Vector3d>(Vector3d()));
  CALL_SUBTEST_9(test_cref_move_ctor<MatrixXd>(MatrixXd::Ones(9, 5)));
  CALL_SUBTEST_9(test_cref_move_ctor<MatrixXd>(MatrixXd(9, 5)));
  CALL_SUBTEST_9(test_cref_move_ctor<Matrix3d>(Matrix3d::Ones()));
  CALL_SUBTEST_9(test_cref_move_ctor<Matrix3d>(Matrix3d()));
  CALL_SUBTEST_10(test_contiguous_ref_no_copy(VectorXd(9)));
  CALL_SUBTEST_10(test_contiguous_ref_no_copy(Vector3d()));
  CALL_SUBTEST_10(test_contiguous_ref_no_copy(MatrixXd(9, 5)));
  CALL_SUBTEST_10(test_contiguous_ref_no_copy(Matrix3d()));
  CALL_SUBTEST_10(test_ref_alignment_matching());
}