#include <gtest/gtest.h>
#include <iomanip>
#include <iostream>

namespace libk {
#include "../libk/stdlib/linked_list_allocator.c"

std::ostream &
operator<<(std::ostream &os, const Chunk &b)
{
  for (const Chunk *iter = &b; iter != nullptr; iter = iter->next) {
    os << iter << "   used=" << iter->used << "  size=" << std::setw(4) << iter->size << "  next=" << iter->next
       << std::endl;
  }
  return os;
}
}; // namespace libk

#include "allocator.hh"

TEST(UninitializedAllocator, malloc) { EXPECT_EQ(libk::malloc(1024), nullptr); }

TEST_F(TestAllocator, mallocMoreThanAvialable)
{
  void *ptr = libk::malloc(memory_size);
  EXPECT_EQ(ptr, nullptr) << *libk::begin;
}

TEST_F(TestAllocator, mallocExactlyAvialable)
{
  void *ptr = libk::malloc(memory_size - sizeof(libk::Chunk));
  EXPECT_NE(ptr, nullptr) << *libk::begin;
}

TEST_F(TestAllocator, malloc)
{
  libk::Chunk *begin = libk::begin;

  void *ptr0 = libk::malloc(1024);
  EXPECT_NE(ptr0, nullptr) << *libk::begin;
  EXPECT_EQ(reinterpret_cast<std::uintptr_t>(ptr0),
            reinterpret_cast<std::uintptr_t>(libk::begin) + sizeof(libk::Chunk));
  EXPECT_EQ(begin->used, 1);
  EXPECT_EQ(begin->size, 1024);
  ASSERT_NE(begin->next, nullptr);
  begin = begin->next;

  void *ptr1 = libk::malloc(512);
  EXPECT_NE(ptr1, nullptr) << *libk::begin;
  EXPECT_EQ(reinterpret_cast<std::uintptr_t>(ptr1),
            reinterpret_cast<std::uintptr_t>(libk::begin) + 2 * sizeof(libk::Chunk) + 1024);
  EXPECT_EQ(begin->used, 1);
  EXPECT_EQ(begin->size, 512);
  ASSERT_NE(begin->next, nullptr);
}

TEST_F(TestAllocator, freeNullptr)
{
  void *ptr0 = libk::malloc(1024);
  EXPECT_NE(ptr0, nullptr) << *libk::begin;
  void *ptr1 = libk::malloc(512);
  EXPECT_NE(ptr1, nullptr) << *libk::begin;

  libk::free(nullptr);
  libk::Chunk *begin = libk::begin;
  EXPECT_EQ(begin->used, 1);
  EXPECT_NE(begin->next, nullptr);
  begin = begin->next;
  EXPECT_EQ(begin->used, 1);
  EXPECT_NE(begin->next, nullptr);
  begin = begin->next;
  EXPECT_EQ(begin->used, 0);
  EXPECT_EQ(begin->next, nullptr);
}

TEST_F(TestAllocator, free)
{
  void *ptr0 = libk::malloc(1024);
  EXPECT_NE(ptr0, nullptr) << *libk::begin;
  void *ptr1 = libk::malloc(512);
  EXPECT_NE(ptr1, nullptr) << *libk::begin;

  libk::free(ptr0);
  libk::Chunk *begin = libk::begin;
  EXPECT_EQ(begin->used, 0) << ptr0 << ": ptr0" << std::endl << *libk::begin;
  EXPECT_NE(begin->next, nullptr);
  begin = begin->next;
  EXPECT_EQ(begin->used, 1);
  EXPECT_NE(begin->next, nullptr);
  begin = begin->next;
  EXPECT_EQ(begin->used, 0);
  EXPECT_EQ(begin->next, nullptr);

  libk::free(ptr1);
  begin = libk::begin;
  EXPECT_EQ(begin->used, 0) << ptr0 << ": ptr0" << std::endl << *libk::begin;
  EXPECT_EQ(begin->next, nullptr);
}