/*
 *  Copyright 2008-2013 NVIDIA Corporation
 *  Modifications Copyright© 2019 Advanced Micro Devices, Inc. All rights reserved.
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  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.
 */
 
#include <unittest/unittest.h>
#include <thrust/binary_search.h>
#include <thrust/functional.h>

#include <thrust/detail/allocator/allocator_traits.h>
#include <thrust/sequence.h>
#include <thrust/sort.h>

//////////////////////
// Vector Functions //
//////////////////////

// convert xxx_vector<T1> to xxx_vector<T2>
template <class ExampleVector, typename NewType>
struct vector_like
{
    typedef typename ExampleVector::allocator_type alloc;
    typedef typename thrust::detail::allocator_traits<alloc> alloc_traits;
    typedef typename alloc_traits::template rebind_alloc<NewType> new_alloc;
    typedef thrust::detail::vector_base<NewType, new_alloc> type;
};

template <class Vector>
void TestVectorLowerBoundDescendingSimple(void)
{
    typedef typename Vector::value_type T;

    Vector vec(5);

    vec[0] = 8;
    vec[1] = 7;
    vec[2] = 5;
    vec[3] = 2;
    vec[4] = 0;

    Vector input(10);
    thrust::sequence(input.begin(), input.end());

    typedef typename Vector::difference_type int_type;
    typedef typename vector_like<Vector, int_type>::type IntVector;

    // test with integral output type
    IntVector integral_output(10);
    typename IntVector::iterator output_end = thrust::lower_bound(vec.begin(), vec.end(), input.begin(), input.end(), integral_output.begin(), thrust::greater<T>());

    ASSERT_EQUAL_QUIET(integral_output.end(), output_end);

    ASSERT_EQUAL(4, integral_output[0]);
    ASSERT_EQUAL(4, integral_output[1]);
    ASSERT_EQUAL(3, integral_output[2]);
    ASSERT_EQUAL(3, integral_output[3]);
    ASSERT_EQUAL(3, integral_output[4]);
    ASSERT_EQUAL(2, integral_output[5]);
    ASSERT_EQUAL(2, integral_output[6]);
    ASSERT_EQUAL(1, integral_output[7]);
    ASSERT_EQUAL(0, integral_output[8]);
    ASSERT_EQUAL(0, integral_output[9]);
}
DECLARE_VECTOR_UNITTEST(TestVectorLowerBoundDescendingSimple);


template <class Vector>
void TestVectorUpperBoundDescendingSimple(void)
{
    Vector vec(5);

    vec[0] = 8;
    vec[1] = 7;
    vec[2] = 5;
    vec[3] = 2;
    vec[4] = 0;

    Vector input(10);
    thrust::sequence(input.begin(), input.end());

    typedef typename Vector::difference_type int_type;
    typedef typename Vector::value_type T;
    typedef typename vector_like<Vector, int_type>::type IntVector;

    // test with integral output type
    IntVector integral_output(10);
    typename IntVector::iterator output_end = thrust::upper_bound(vec.begin(), vec.end(), input.begin(), input.end(), integral_output.begin(), thrust::greater<T>());

    ASSERT_EQUAL_QUIET(output_end, integral_output.end());

    ASSERT_EQUAL(5, integral_output[0]);
    ASSERT_EQUAL(4, integral_output[1]);
    ASSERT_EQUAL(4, integral_output[2]);
    ASSERT_EQUAL(3, integral_output[3]);
    ASSERT_EQUAL(3, integral_output[4]);
    ASSERT_EQUAL(3, integral_output[5]);
    ASSERT_EQUAL(2, integral_output[6]);
    ASSERT_EQUAL(2, integral_output[7]);
    ASSERT_EQUAL(1, integral_output[8]);
    ASSERT_EQUAL(0, integral_output[9]);
}
DECLARE_VECTOR_UNITTEST(TestVectorUpperBoundDescendingSimple);


template <class Vector>
void TestVectorBinarySearchDescendingSimple(void)
{
  Vector vec(5);

  vec[0] = 8;
  vec[1] = 7;
  vec[2] = 5;
  vec[3] = 2;
  vec[4] = 0;

  Vector input(10);
  thrust::sequence(input.begin(), input.end());

  typedef typename vector_like<Vector, bool>::type BoolVector;
  typedef typename Vector::difference_type int_type;
  typedef typename Vector::value_type T;
  typedef typename vector_like<Vector,  int_type>::type IntVector;

  // test with boolean output type
  BoolVector bool_output(10);
  typename BoolVector::iterator bool_output_end = thrust::binary_search(vec.begin(), vec.end(), input.begin(), input.end(), bool_output.begin(), thrust::greater<T>());

  ASSERT_EQUAL_QUIET(bool_output_end, bool_output.end());

  ASSERT_EQUAL(true,  bool_output[0]);
  ASSERT_EQUAL(false, bool_output[1]);
  ASSERT_EQUAL(true,  bool_output[2]);
  ASSERT_EQUAL(false, bool_output[3]);
  ASSERT_EQUAL(false, bool_output[4]);
  ASSERT_EQUAL(true,  bool_output[5]);
  ASSERT_EQUAL(false, bool_output[6]);
  ASSERT_EQUAL(true,  bool_output[7]);
  ASSERT_EQUAL(true,  bool_output[8]);
  ASSERT_EQUAL(false, bool_output[9]);

  // test with integral output type
  IntVector integral_output(10, 2);
  typename IntVector::iterator int_output_end = thrust::binary_search(vec.begin(), vec.end(), input.begin(), input.end(), integral_output.begin(), thrust::greater<T>());

  ASSERT_EQUAL_QUIET(int_output_end, integral_output.end());

  ASSERT_EQUAL(1, integral_output[0]);
  ASSERT_EQUAL(0, integral_output[1]);
  ASSERT_EQUAL(1, integral_output[2]);
  ASSERT_EQUAL(0, integral_output[3]);
  ASSERT_EQUAL(0, integral_output[4]);
  ASSERT_EQUAL(1, integral_output[5]);
  ASSERT_EQUAL(0, integral_output[6]);
  ASSERT_EQUAL(1, integral_output[7]);
  ASSERT_EQUAL(1, integral_output[8]);
  ASSERT_EQUAL(0, integral_output[9]);
}
DECLARE_VECTOR_UNITTEST(TestVectorBinarySearchDescendingSimple);


template <typename T>
struct TestVectorLowerBoundDescending
{
  void operator()(const size_t n)
  {
    thrust::host_vector<T>   h_vec = unittest::random_integers<T>(n); thrust::sort(h_vec.begin(), h_vec.end(), thrust::greater<T>());
    thrust::device_vector<T> d_vec = h_vec;

    thrust::host_vector<T>   h_input = unittest::random_integers<T>(2*n);
    thrust::device_vector<T> d_input = h_input;

    typedef typename thrust::host_vector<T>::difference_type int_type;
    thrust::host_vector<int_type>   h_output(2*n);
    thrust::device_vector<int_type> d_output(2*n);

    thrust::lower_bound(h_vec.begin(), h_vec.end(), h_input.begin(), h_input.end(), h_output.begin(), thrust::greater<T>());
    thrust::lower_bound(d_vec.begin(), d_vec.end(), d_input.begin(), d_input.end(), d_output.begin(), thrust::greater<T>());

    ASSERT_EQUAL(h_output, d_output);
  }
};
VariableUnitTest<TestVectorLowerBoundDescending, SignedIntegralTypes> TestVectorLowerBoundDescendingInstance;


template <typename T>
struct TestVectorUpperBoundDescending
{
  void operator()(const size_t n)
  {
    thrust::host_vector<T>   h_vec = unittest::random_integers<T>(n); thrust::sort(h_vec.begin(), h_vec.end(), thrust::greater<T>());
    thrust::device_vector<T> d_vec = h_vec;

    thrust::host_vector<T>   h_input = unittest::random_integers<T>(2*n);
    thrust::device_vector<T> d_input = h_input;

    typedef typename thrust::host_vector<T>::difference_type int_type;
    thrust::host_vector<int_type>   h_output(2*n);
    thrust::device_vector<int_type> d_output(2*n);

    thrust::upper_bound(h_vec.begin(), h_vec.end(), h_input.begin(), h_input.end(), h_output.begin(), thrust::greater<T>());
    thrust::upper_bound(d_vec.begin(), d_vec.end(), d_input.begin(), d_input.end(), d_output.begin(), thrust::greater<T>());

    ASSERT_EQUAL(h_output, d_output);
  }
};
VariableUnitTest<TestVectorUpperBoundDescending, SignedIntegralTypes> TestVectorUpperBoundDescendingInstance;

template <typename T>
struct TestVectorBinarySearchDescending
{
  void operator()(const size_t n)
  {
    thrust::host_vector<T>   h_vec = unittest::random_integers<T>(n); thrust::sort(h_vec.begin(), h_vec.end(), thrust::greater<T>());
    thrust::device_vector<T> d_vec = h_vec;

    thrust::host_vector<T>   h_input = unittest::random_integers<T>(2*n);
    thrust::device_vector<T> d_input = h_input;

    typedef typename thrust::host_vector<T>::difference_type int_type;
    thrust::host_vector<int_type>   h_output(2*n);
    thrust::device_vector<int_type> d_output(2*n);

    thrust::binary_search(h_vec.begin(), h_vec.end(), h_input.begin(), h_input.end(), h_output.begin(), thrust::greater<T>());
    thrust::binary_search(d_vec.begin(), d_vec.end(), d_input.begin(), d_input.end(), d_output.begin(), thrust::greater<T>());

    ASSERT_EQUAL(h_output, d_output);
  }
};
VariableUnitTest<TestVectorBinarySearchDescending, SignedIntegralTypes> TestVectorBinarySearchDescendingInstance;
