/*
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * 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 <cstddef>

#include <thrift/test/gen-cpp2/minimize_padding_types.h>

#include <folly/portability/GTest.h>

using namespace apache::thrift::test;

TEST(minimize_padding_test, empty) {
  EXPECT_EQ(1, sizeof(empty));
}

struct optimal {
  std::string i;
  std::vector<int8_t> k;
  std::set<int8_t> m;
  std::map<int8_t, int8_t> o;
  double g;
  int64_t e;
  float h;
  int32_t c;
  int32_t q;
  test_enum f;
  int16_t a;
  int8_t d;
  int8_t j;
  int8_t l;
  int8_t n;
  int8_t p;
  bool b;
};

template <class Ret, class T>
size_t thrift_member_offset(Ret (T::*func)() &) {
  T t;
  auto& member = *(t.*func)();
  return reinterpret_cast<char*>(&member) - reinterpret_cast<char*>(&t);
}

TEST(minimize_padding_test, reorder_nonoptimal) {
  EXPECT_EQ(sizeof(optimal), sizeof(nonoptimal));
  EXPECT_EQ(sizeof(nonoptimal_struct), 12);
  EXPECT_EQ(sizeof(nonoptimal_struct_with_structured_annotation), 12);
  EXPECT_EQ(thrift_member_offset(&nonoptimal_struct::big_ref<>), 0);
  // The 'small' field will be the first field, since it has a custom type.
  EXPECT_EQ(
      thrift_member_offset(&nonoptimal_struct_with_custom_type::small_ref<>),
      0);
}

TEST(minimize_padding_test, preserve_order_if_same_sizes) {
  EXPECT_LT(
      thrift_member_offset(&same_sizes::a_ref<>),
      thrift_member_offset(&same_sizes::b_ref<>));
  EXPECT_LT(
      thrift_member_offset(&same_sizes::b_ref<>),
      thrift_member_offset(&same_sizes::c_ref<>));
  EXPECT_LT(
      thrift_member_offset(&same_sizes::c_ref<>),
      thrift_member_offset(&same_sizes::d_ref<>));
}

struct reordered_ref_type {
  std::unique_ptr<int8_t> b;
  std::unique_ptr<int8_t> d;
  int8_t a;
  int8_t c;
};

TEST(minimize_padding_test, reorder_ref_type) {
  EXPECT_EQ(sizeof(reordered_ref_type), sizeof(ref_type));
}

TEST(minimize_padding_test, enums) {
  EXPECT_EQ(sizeof(byte_enum), 1);
  EXPECT_EQ(sizeof(short_enum), 2);
  EXPECT_EQ(sizeof(unsigned_int_enum), 4);
  EXPECT_EQ(sizeof(minimized_enums), 8);
  EXPECT_EQ(sizeof(enums), 12);
}