// Copyright 2016 PDFium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "core/fxcrt/retain_ptr.h"

#include <utility>
#include <vector>

#include "testing/gtest/include/gtest/gtest.h"

namespace fxcrt {
namespace {

class PseudoRetainable {
 public:
  PseudoRetainable() : retain_count_(0), release_count_(0) {}
  void Retain() { ++retain_count_; }
  void Release() { ++release_count_; }
  int retain_count() const { return retain_count_; }
  int release_count() const { return release_count_; }

 private:
  int retain_count_;
  int release_count_;
};

}  // namespace

TEST(RetainPtr, Null) {
  RetainPtr<PseudoRetainable> ptr;
  EXPECT_EQ(nullptr, ptr.Get());
}

TEST(RetainPtr, Normal) {
  PseudoRetainable obj;
  {
    RetainPtr<PseudoRetainable> ptr(&obj);
    EXPECT_EQ(&obj, ptr.Get());
    EXPECT_EQ(1, obj.retain_count());
    EXPECT_EQ(0, obj.release_count());
  }
  EXPECT_EQ(1, obj.retain_count());
  EXPECT_EQ(1, obj.release_count());
}

TEST(RetainPtr, CopyCtor) {
  PseudoRetainable obj;
  {
    RetainPtr<PseudoRetainable> ptr1(&obj);
    {
      RetainPtr<PseudoRetainable> ptr2(ptr1);
      EXPECT_EQ(2, obj.retain_count());
      EXPECT_EQ(0, obj.release_count());
    }
    EXPECT_EQ(2, obj.retain_count());
    EXPECT_EQ(1, obj.release_count());
  }
  EXPECT_EQ(2, obj.retain_count());
  EXPECT_EQ(2, obj.release_count());
}

TEST(RetainPtr, MoveCtor) {
  PseudoRetainable obj;
  {
    RetainPtr<PseudoRetainable> ptr1(&obj);
    {
      RetainPtr<PseudoRetainable> ptr2(std::move(ptr1));
      EXPECT_EQ(nullptr, ptr1.Get());
      EXPECT_EQ(&obj, ptr2.Get());
      EXPECT_EQ(1, obj.retain_count());
      EXPECT_EQ(0, obj.release_count());
    }
    EXPECT_EQ(1, obj.retain_count());
    EXPECT_EQ(1, obj.release_count());
  }
  EXPECT_EQ(1, obj.retain_count());
  EXPECT_EQ(1, obj.release_count());
}

TEST(RetainPtr, ResetNull) {
  PseudoRetainable obj;
  {
    RetainPtr<PseudoRetainable> ptr(&obj);
    ptr.Reset();
    EXPECT_EQ(1, obj.retain_count());
    EXPECT_EQ(1, obj.release_count());
  }
  EXPECT_EQ(1, obj.retain_count());
  EXPECT_EQ(1, obj.release_count());
}

TEST(RetainPtr, Reset) {
  PseudoRetainable obj1;
  PseudoRetainable obj2;
  {
    RetainPtr<PseudoRetainable> ptr(&obj1);
    ptr.Reset(&obj2);
    EXPECT_EQ(1, obj1.retain_count());
    EXPECT_EQ(1, obj1.release_count());
    EXPECT_EQ(1, obj2.retain_count());
    EXPECT_EQ(0, obj2.release_count());
  }
  EXPECT_EQ(1, obj1.retain_count());
  EXPECT_EQ(1, obj1.release_count());
  EXPECT_EQ(1, obj2.retain_count());
  EXPECT_EQ(1, obj2.release_count());
}

TEST(RetainPtr, Swap) {
  PseudoRetainable obj1;
  PseudoRetainable obj2;
  {
    RetainPtr<PseudoRetainable> ptr1(&obj1);
    {
      RetainPtr<PseudoRetainable> ptr2(&obj2);
      ptr1.Swap(ptr2);
      EXPECT_EQ(1, obj1.retain_count());
      EXPECT_EQ(0, obj1.release_count());
      EXPECT_EQ(1, obj2.retain_count());
      EXPECT_EQ(0, obj2.release_count());
    }
    EXPECT_EQ(1, obj1.retain_count());
    EXPECT_EQ(1, obj1.release_count());
    EXPECT_EQ(1, obj2.retain_count());
    EXPECT_EQ(0, obj2.release_count());
  }
  EXPECT_EQ(1, obj1.retain_count());
  EXPECT_EQ(1, obj1.release_count());
  EXPECT_EQ(1, obj2.retain_count());
  EXPECT_EQ(1, obj2.release_count());
}

TEST(RetainPtr, Leak) {
  PseudoRetainable obj;
  PseudoRetainable* leak;
  {
    RetainPtr<PseudoRetainable> ptr(&obj);
    leak = ptr.Leak();
    EXPECT_EQ(1, obj.retain_count());
    EXPECT_EQ(0, obj.release_count());
  }
  EXPECT_EQ(1, obj.retain_count());
  EXPECT_EQ(0, obj.release_count());
  {
    RetainPtr<PseudoRetainable> ptr;
    ptr.Unleak(leak);
    EXPECT_EQ(1, obj.retain_count());
    EXPECT_EQ(0, obj.release_count());
  }
  EXPECT_EQ(1, obj.retain_count());
  EXPECT_EQ(1, obj.release_count());
}

TEST(RetainPtr, SwapNull) {
  PseudoRetainable obj1;
  {
    RetainPtr<PseudoRetainable> ptr1(&obj1);
    {
      RetainPtr<PseudoRetainable> ptr2;
      ptr1.Swap(ptr2);
      EXPECT_FALSE(ptr1);
      EXPECT_TRUE(ptr2);
      EXPECT_EQ(1, obj1.retain_count());
      EXPECT_EQ(0, obj1.release_count());
    }
    EXPECT_EQ(1, obj1.retain_count());
    EXPECT_EQ(1, obj1.release_count());
  }
  EXPECT_EQ(1, obj1.retain_count());
  EXPECT_EQ(1, obj1.release_count());
}

TEST(RetainPtr, Assign) {
  PseudoRetainable obj;
  {
    RetainPtr<PseudoRetainable> ptr(&obj);
    {
      RetainPtr<PseudoRetainable> ptr2;
      ptr2 = ptr;
      EXPECT_EQ(2, obj.retain_count());
      EXPECT_EQ(0, obj.release_count());
    }
    EXPECT_EQ(2, obj.retain_count());
    EXPECT_EQ(1, obj.release_count());
  }
  EXPECT_EQ(2, obj.retain_count());
  EXPECT_EQ(2, obj.release_count());
}

TEST(RetainPtr, MoveAssign) {
  PseudoRetainable obj;
  {
    RetainPtr<PseudoRetainable> ptr1(&obj);
    {
      RetainPtr<PseudoRetainable> ptr2;
      EXPECT_EQ(&obj, ptr1.Get());
      EXPECT_EQ(nullptr, ptr2.Get());
      ptr2 = std::move(ptr1);
      EXPECT_EQ(nullptr, ptr1.Get());
      EXPECT_EQ(&obj, ptr2.Get());
      EXPECT_EQ(1, obj.retain_count());
      EXPECT_EQ(0, obj.release_count());
    }
    EXPECT_EQ(1, obj.retain_count());
    EXPECT_EQ(1, obj.release_count());
  }
  EXPECT_EQ(1, obj.retain_count());
  EXPECT_EQ(1, obj.release_count());
}

TEST(RetainPtr, Equals) {
  PseudoRetainable obj1;
  PseudoRetainable obj2;
  RetainPtr<PseudoRetainable> null_ptr1;
  RetainPtr<PseudoRetainable> obj1_ptr1(&obj1);
  RetainPtr<PseudoRetainable> obj2_ptr1(&obj2);
  {
    RetainPtr<PseudoRetainable> null_ptr2;
    EXPECT_TRUE(null_ptr1 == null_ptr2);

    RetainPtr<PseudoRetainable> obj1_ptr2(&obj1);
    EXPECT_TRUE(obj1_ptr1 == obj1_ptr2);

    RetainPtr<PseudoRetainable> obj2_ptr2(&obj2);
    EXPECT_TRUE(obj2_ptr1 == obj2_ptr2);
  }
  EXPECT_FALSE(null_ptr1 == obj1_ptr1);
  EXPECT_FALSE(null_ptr1 == obj2_ptr1);
  EXPECT_FALSE(obj1_ptr1 == obj2_ptr1);
}

TEST(RetainPtr, NotEquals) {
  PseudoRetainable obj1;
  PseudoRetainable obj2;
  RetainPtr<PseudoRetainable> null_ptr1;
  RetainPtr<PseudoRetainable> obj1_ptr1(&obj1);
  RetainPtr<PseudoRetainable> obj2_ptr1(&obj2);
  {
    RetainPtr<PseudoRetainable> null_ptr2;
    RetainPtr<PseudoRetainable> obj1_ptr2(&obj1);
    RetainPtr<PseudoRetainable> obj2_ptr2(&obj2);
    EXPECT_FALSE(null_ptr1 != null_ptr2);
    EXPECT_FALSE(obj1_ptr1 != obj1_ptr2);
    EXPECT_FALSE(obj2_ptr1 != obj2_ptr2);
  }
  EXPECT_TRUE(null_ptr1 != obj1_ptr1);
  EXPECT_TRUE(null_ptr1 != obj2_ptr1);
  EXPECT_TRUE(obj1_ptr1 != obj2_ptr1);
}

TEST(RetainPtr, LessThan) {
  PseudoRetainable objs[2];
  RetainPtr<PseudoRetainable> obj1_ptr(&objs[0]);
  RetainPtr<PseudoRetainable> obj2_ptr(&objs[1]);
  EXPECT_TRUE(obj1_ptr < obj2_ptr);
  EXPECT_FALSE(obj2_ptr < obj1_ptr);
}

TEST(RetainPtr, Bool) {
  PseudoRetainable obj1;
  RetainPtr<PseudoRetainable> null_ptr;
  RetainPtr<PseudoRetainable> obj1_ptr(&obj1);
  bool null_bool = !!null_ptr;
  bool obj1_bool = !!obj1_ptr;
  EXPECT_FALSE(null_bool);
  EXPECT_TRUE(obj1_bool);
}

TEST(RetainPtr, MakeRetained) {
  auto ptr = pdfium::MakeRetain<Retainable>();
  EXPECT_TRUE(ptr->HasOneRef());
  {
    RetainPtr<Retainable> other = ptr;
    EXPECT_FALSE(ptr->HasOneRef());
  }
  EXPECT_TRUE(ptr->HasOneRef());
}

TEST(RetainPtr, VectorMove) {
  // Proves move ctor is selected by std::vector over copy/delete, this
  // may require the ctor to be marked "noexcept".
  PseudoRetainable obj;
  {
    RetainPtr<PseudoRetainable> ptr(&obj);
    std::vector<RetainPtr<PseudoRetainable>> vec1;
    vec1.push_back(std::move(ptr));
    EXPECT_EQ(1, obj.retain_count());
    EXPECT_EQ(0, obj.release_count());

    std::vector<RetainPtr<PseudoRetainable>> vec2 = std::move(vec1);
    EXPECT_EQ(1, obj.retain_count());
    EXPECT_EQ(0, obj.release_count());

    vec2.resize(4096);
    EXPECT_EQ(1, obj.retain_count());
    EXPECT_EQ(0, obj.release_count());
  }
  EXPECT_EQ(1, obj.retain_count());
  EXPECT_EQ(1, obj.release_count());
}

}  // namespace fxcrt