/*
 * Copyright (C) 2012 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS 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 APPLE INC. OR ITS 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
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "wtf/HashSet.h"

#include "testing/gtest/include/gtest/gtest.h"
#include "wtf/PtrUtil.h"
#include "wtf/RefCounted.h"
#include <memory>

namespace WTF {

namespace {

template <unsigned size>
void testReserveCapacity();
template <>
void testReserveCapacity<0>() {}
template <unsigned size>
void testReserveCapacity() {
  HashSet<int> testSet;

  // Initial capacity is zero.
  EXPECT_EQ(0UL, testSet.capacity());

  testSet.reserveCapacityForSize(size);
  const unsigned initialCapacity = testSet.capacity();
  const unsigned minimumTableSize = HashTraits<int>::minimumTableSize;

  // reserveCapacityForSize should respect minimumTableSize.
  EXPECT_GE(initialCapacity, minimumTableSize);

  // Adding items up to size should never change the capacity.
  for (size_t i = 0; i < size; ++i) {
    testSet.insert(i + 1);  // Avoid adding '0'.
    EXPECT_EQ(initialCapacity, testSet.capacity());
  }

  // Adding items up to less than half the capacity should not change the
  // capacity.
  unsigned capacityLimit = initialCapacity / 2 - 1;
  for (size_t i = size; i < capacityLimit; ++i) {
    testSet.insert(i + 1);
    EXPECT_EQ(initialCapacity, testSet.capacity());
  }

  // Adding one more item increases the capacity.
  testSet.insert(capacityLimit + 1);
  EXPECT_GT(testSet.capacity(), initialCapacity);

  testReserveCapacity<size - 1>();
}

TEST(HashSetTest, ReserveCapacity) {
  testReserveCapacity<128>();
}

struct Dummy {
  Dummy(bool& deleted) : deleted(deleted) {}

  ~Dummy() { deleted = true; }

  bool& deleted;
};

TEST(HashSetTest, HashSetOwnPtr) {
  bool deleted1 = false, deleted2 = false;

  typedef HashSet<std::unique_ptr<Dummy>> OwnPtrSet;
  OwnPtrSet set;

  Dummy* ptr1 = new Dummy(deleted1);
  {
    // AddResult in a separate scope to avoid assertion hit,
    // since we modify the container further.
    HashSet<std::unique_ptr<Dummy>>::AddResult res1 =
        set.insert(WTF::wrapUnique(ptr1));
    EXPECT_EQ(ptr1, res1.storedValue->get());
  }

  EXPECT_FALSE(deleted1);
  EXPECT_EQ(1UL, set.size());
  OwnPtrSet::iterator it1 = set.find(ptr1);
  EXPECT_NE(set.end(), it1);
  EXPECT_EQ(ptr1, (*it1).get());

  Dummy* ptr2 = new Dummy(deleted2);
  {
    HashSet<std::unique_ptr<Dummy>>::AddResult res2 =
        set.insert(WTF::wrapUnique(ptr2));
    EXPECT_EQ(res2.storedValue->get(), ptr2);
  }

  EXPECT_FALSE(deleted2);
  EXPECT_EQ(2UL, set.size());
  OwnPtrSet::iterator it2 = set.find(ptr2);
  EXPECT_NE(set.end(), it2);
  EXPECT_EQ(ptr2, (*it2).get());

  set.erase(ptr1);
  EXPECT_TRUE(deleted1);

  set.clear();
  EXPECT_TRUE(deleted2);
  EXPECT_TRUE(set.isEmpty());

  deleted1 = false;
  deleted2 = false;
  {
    OwnPtrSet set;
    set.insert(WTF::makeUnique<Dummy>(deleted1));
    set.insert(WTF::makeUnique<Dummy>(deleted2));
  }
  EXPECT_TRUE(deleted1);
  EXPECT_TRUE(deleted2);

  deleted1 = false;
  deleted2 = false;
  std::unique_ptr<Dummy> ownPtr1;
  std::unique_ptr<Dummy> ownPtr2;
  ptr1 = new Dummy(deleted1);
  ptr2 = new Dummy(deleted2);
  {
    OwnPtrSet set;
    set.insert(WTF::wrapUnique(ptr1));
    set.insert(WTF::wrapUnique(ptr2));
    ownPtr1 = set.take(ptr1);
    EXPECT_EQ(1UL, set.size());
    ownPtr2 = set.takeAny();
    EXPECT_TRUE(set.isEmpty());
  }
  EXPECT_FALSE(deleted1);
  EXPECT_FALSE(deleted2);

  EXPECT_EQ(ptr1, ownPtr1.get());
  EXPECT_EQ(ptr2, ownPtr2.get());
}

class DummyRefCounted : public RefCounted<DummyRefCounted> {
 public:
  DummyRefCounted(bool& isDeleted) : m_isDeleted(isDeleted) {
    m_isDeleted = false;
  }
  ~DummyRefCounted() { m_isDeleted = true; }

  void ref() {
    WTF::RefCounted<DummyRefCounted>::ref();
    ++s_refInvokesCount;
  }

  static int s_refInvokesCount;

 private:
  bool& m_isDeleted;
};

int DummyRefCounted::s_refInvokesCount = 0;

TEST(HashSetTest, HashSetRefPtr) {
  bool isDeleted = false;
  RefPtr<DummyRefCounted> ptr = adoptRef(new DummyRefCounted(isDeleted));
  EXPECT_EQ(0, DummyRefCounted::s_refInvokesCount);
  HashSet<RefPtr<DummyRefCounted>> set;
  set.insert(ptr);
  // Referenced only once (to store a copy in the container).
  EXPECT_EQ(1, DummyRefCounted::s_refInvokesCount);

  DummyRefCounted* rawPtr = ptr.get();

  EXPECT_TRUE(set.contains(rawPtr));
  EXPECT_NE(set.end(), set.find(rawPtr));
  EXPECT_TRUE(set.contains(ptr));
  EXPECT_NE(set.end(), set.find(ptr));

  ptr.clear();
  EXPECT_FALSE(isDeleted);

  set.erase(rawPtr);
  EXPECT_TRUE(isDeleted);
  EXPECT_TRUE(set.isEmpty());
  EXPECT_EQ(1, DummyRefCounted::s_refInvokesCount);
}

class CountCopy final {
 public:
  static int* const kDeletedValue;

  explicit CountCopy(int* counter = nullptr) : m_counter(counter) {}
  CountCopy(const CountCopy& other) : m_counter(other.m_counter) {
    if (m_counter && m_counter != kDeletedValue)
      ++*m_counter;
  }
  CountCopy& operator=(const CountCopy& other) {
    m_counter = other.m_counter;
    if (m_counter && m_counter != kDeletedValue)
      ++*m_counter;
    return *this;
  }
  const int* counter() const { return m_counter; }

 private:
  int* m_counter;
};

int* const CountCopy::kDeletedValue =
    reinterpret_cast<int*>(static_cast<uintptr_t>(-1));

struct CountCopyHashTraits : public GenericHashTraits<CountCopy> {
  static const bool emptyValueIsZero = false;
  static const bool hasIsEmptyValueFunction = true;
  static bool isEmptyValue(const CountCopy& value) { return !value.counter(); }
  static void constructDeletedValue(CountCopy& slot, bool) {
    slot = CountCopy(CountCopy::kDeletedValue);
  }
  static bool isDeletedValue(const CountCopy& value) {
    return value.counter() == CountCopy::kDeletedValue;
  }
};

struct CountCopyHash : public PtrHash<const int*> {
  static unsigned hash(const CountCopy& value) {
    return PtrHash<const int>::hash(value.counter());
  }
  static bool equal(const CountCopy& left, const CountCopy& right) {
    return PtrHash<const int>::equal(left.counter(), right.counter());
  }
  static const bool safeToCompareToEmptyOrDeleted = true;
};

}  // anonymous namespace

template <>
struct HashTraits<CountCopy> : public CountCopyHashTraits {};

template <>
struct DefaultHash<CountCopy> {
  using Hash = CountCopyHash;
};

namespace {

TEST(HashSetTest, MoveShouldNotMakeCopy) {
  HashSet<CountCopy> set;
  int counter = 0;
  set.insert(CountCopy(&counter));

  HashSet<CountCopy> other(set);
  counter = 0;
  set = std::move(other);
  EXPECT_EQ(0, counter);

  counter = 0;
  HashSet<CountCopy> yetAnother(std::move(set));
  EXPECT_EQ(0, counter);
}

class MoveOnly {
 public:
  // kEmpty and kDeleted have special meanings when MoveOnly is used as the key
  // of a hash table.
  enum { kEmpty = 0, kDeleted = -1, kMovedOut = -2 };

  explicit MoveOnly(int value = kEmpty, int id = 0)
      : m_value(value), m_id(id) {}
  MoveOnly(MoveOnly&& other) : m_value(other.m_value), m_id(other.m_id) {
    other.m_value = kMovedOut;
    other.m_id = 0;
  }
  MoveOnly& operator=(MoveOnly&& other) {
    m_value = other.m_value;
    m_id = other.m_id;
    other.m_value = kMovedOut;
    other.m_id = 0;
    return *this;
  }

  int value() const { return m_value; }
  // id() is used for distinguishing MoveOnlys with the same value().
  int id() const { return m_id; }

 private:
  MoveOnly(const MoveOnly&) = delete;
  MoveOnly& operator=(const MoveOnly&) = delete;

  int m_value;
  int m_id;
};

struct MoveOnlyHashTraits : public GenericHashTraits<MoveOnly> {
  // This is actually true, but we pretend that it's false to disable the
  // optimization.
  static const bool emptyValueIsZero = false;

  static const bool hasIsEmptyValueFunction = true;
  static bool isEmptyValue(const MoveOnly& value) {
    return value.value() == MoveOnly::kEmpty;
  }
  static void constructDeletedValue(MoveOnly& slot, bool) {
    slot = MoveOnly(MoveOnly::kDeleted);
  }
  static bool isDeletedValue(const MoveOnly& value) {
    return value.value() == MoveOnly::kDeleted;
  }
};

struct MoveOnlyHash {
  static unsigned hash(const MoveOnly& value) {
    return DefaultHash<int>::Hash::hash(value.value());
  }
  static bool equal(const MoveOnly& left, const MoveOnly& right) {
    return DefaultHash<int>::Hash::equal(left.value(), right.value());
  }
  static const bool safeToCompareToEmptyOrDeleted = true;
};

}  // anonymous namespace

template <>
struct HashTraits<MoveOnly> : public MoveOnlyHashTraits {};

template <>
struct DefaultHash<MoveOnly> {
  using Hash = MoveOnlyHash;
};

namespace {

TEST(HashSetTest, MoveOnlyValue) {
  using TheSet = HashSet<MoveOnly>;
  TheSet set;
  {
    TheSet::AddResult addResult = set.insert(MoveOnly(1, 1));
    EXPECT_TRUE(addResult.isNewEntry);
    EXPECT_EQ(1, addResult.storedValue->value());
    EXPECT_EQ(1, addResult.storedValue->id());
  }
  auto iter = set.find(MoveOnly(1));
  ASSERT_TRUE(iter != set.end());
  EXPECT_EQ(1, iter->value());

  iter = set.find(MoveOnly(2));
  EXPECT_TRUE(iter == set.end());

  for (int i = 2; i < 32; ++i) {
    TheSet::AddResult addResult = set.insert(MoveOnly(i, i));
    EXPECT_TRUE(addResult.isNewEntry);
    EXPECT_EQ(i, addResult.storedValue->value());
    EXPECT_EQ(i, addResult.storedValue->id());
  }

  iter = set.find(MoveOnly(1));
  ASSERT_TRUE(iter != set.end());
  EXPECT_EQ(1, iter->value());
  EXPECT_EQ(1, iter->id());

  iter = set.find(MoveOnly(7));
  ASSERT_TRUE(iter != set.end());
  EXPECT_EQ(7, iter->value());
  EXPECT_EQ(7, iter->id());

  {
    TheSet::AddResult addResult =
        set.insert(MoveOnly(7, 777));  // With different ID for identification.
    EXPECT_FALSE(addResult.isNewEntry);
    EXPECT_EQ(7, addResult.storedValue->value());
    EXPECT_EQ(7, addResult.storedValue->id());
  }

  set.erase(MoveOnly(11));
  iter = set.find(MoveOnly(11));
  EXPECT_TRUE(iter == set.end());

  MoveOnly thirteen(set.take(MoveOnly(13)));
  EXPECT_EQ(13, thirteen.value());
  EXPECT_EQ(13, thirteen.id());
  iter = set.find(MoveOnly(13));
  EXPECT_TRUE(iter == set.end());

  set.clear();
}

TEST(HashSetTest, UniquePtr) {
  using Pointer = std::unique_ptr<int>;
  using Set = HashSet<Pointer>;
  Set set;
  int* onePointer = new int(1);
  {
    Set::AddResult addResult = set.insert(Pointer(onePointer));
    EXPECT_TRUE(addResult.isNewEntry);
    EXPECT_EQ(onePointer, addResult.storedValue->get());
    EXPECT_EQ(1, **addResult.storedValue);
  }
  auto iter = set.find(onePointer);
  ASSERT_TRUE(iter != set.end());
  EXPECT_EQ(onePointer, iter->get());

  Pointer nonexistent(new int(42));
  iter = set.find(nonexistent.get());
  EXPECT_TRUE(iter == set.end());

  // Insert more to cause a rehash.
  for (int i = 2; i < 32; ++i) {
    Set::AddResult addResult = set.insert(Pointer(new int(i)));
    EXPECT_TRUE(addResult.isNewEntry);
    EXPECT_EQ(i, **addResult.storedValue);
  }

  iter = set.find(onePointer);
  ASSERT_TRUE(iter != set.end());
  EXPECT_EQ(onePointer, iter->get());

  Pointer one(set.take(onePointer));
  ASSERT_TRUE(one);
  EXPECT_EQ(onePointer, one.get());

  Pointer empty(set.take(nonexistent.get()));
  EXPECT_TRUE(!empty);

  iter = set.find(onePointer);
  EXPECT_TRUE(iter == set.end());

  // Re-insert to the deleted slot.
  {
    Set::AddResult addResult = set.insert(std::move(one));
    EXPECT_TRUE(addResult.isNewEntry);
    EXPECT_EQ(onePointer, addResult.storedValue->get());
    EXPECT_EQ(1, **addResult.storedValue);
  }
}

bool isOneTwoThree(const HashSet<int>& set) {
  return set.size() == 3 && set.contains(1) && set.contains(2) &&
         set.contains(3);
}

HashSet<int> returnOneTwoThree() {
  return {1, 2, 3};
}

TEST(HashSetTest, InitializerList) {
  HashSet<int> empty({});
  EXPECT_TRUE(empty.isEmpty());

  HashSet<int> one({1});
  EXPECT_EQ(1u, one.size());
  EXPECT_TRUE(one.contains(1));

  HashSet<int> oneTwoThree({1, 2, 3});
  EXPECT_EQ(3u, oneTwoThree.size());
  EXPECT_TRUE(oneTwoThree.contains(1));
  EXPECT_TRUE(oneTwoThree.contains(2));
  EXPECT_TRUE(oneTwoThree.contains(3));

  // Put some jank so we can check if the assignments later can clear them.
  empty.insert(9999);
  one.insert(9999);
  oneTwoThree.insert(9999);

  empty = {};
  EXPECT_TRUE(empty.isEmpty());

  one = {1};
  EXPECT_EQ(1u, one.size());
  EXPECT_TRUE(one.contains(1));

  oneTwoThree = {1, 2, 3};
  EXPECT_EQ(3u, oneTwoThree.size());
  EXPECT_TRUE(oneTwoThree.contains(1));
  EXPECT_TRUE(oneTwoThree.contains(2));
  EXPECT_TRUE(oneTwoThree.contains(3));

  oneTwoThree = {3, 1, 1, 2, 1, 1, 3};
  EXPECT_EQ(3u, oneTwoThree.size());
  EXPECT_TRUE(oneTwoThree.contains(1));
  EXPECT_TRUE(oneTwoThree.contains(2));
  EXPECT_TRUE(oneTwoThree.contains(3));

  // Other ways of construction: as a function parameter and in a return
  // statement.
  EXPECT_TRUE(isOneTwoThree({1, 2, 3}));
  EXPECT_TRUE(isOneTwoThree(returnOneTwoThree()));
}

}  // anonymous namespace

}  // namespace WTF