// Copyright 2014 Dolphin Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later

#include <gtest/gtest.h>

#include <memory>
#include <unordered_set>

#include "Common/CommonTypes.h"
#include "Core/HW/GPFifo.h"
#include "Core/HW/MMIO.h"
#include "Core/System.h"

// Tests that the UniqueID function returns a "unique enough" identifier
// number: that is, it is unique in the address ranges we care about.
TEST(UniqueID, UniqueEnough)
{
  std::unordered_set<u32> ids;
  for (u32 i = 0x0C000000; i < 0x0C010000; ++i)
  {
    u32 unique_id = MMIO::UniqueID(i);
    EXPECT_FALSE(ids.contains(unique_id));
    ids.insert(unique_id);
  }
  for (u32 i = 0x0D000000; i < 0x0D010000; ++i)
  {
    u32 unique_id = MMIO::UniqueID(i);
    EXPECT_FALSE(ids.contains(unique_id));
    ids.insert(unique_id);
  }
}

TEST(IsMMIOAddress, SpecialAddresses)
{
  constexpr bool is_wii = true;

  // WG Pipe address, should not be handled by MMIO.
  EXPECT_FALSE(MMIO::IsMMIOAddress(GPFifo::GATHER_PIPE_PHYSICAL_ADDRESS, is_wii));

  // Locked L1 cache allocation.
  EXPECT_FALSE(MMIO::IsMMIOAddress(0xE0000000, is_wii));

  // Uncached mirror of MEM1, shouldn't be handled by MMIO
  EXPECT_FALSE(MMIO::IsMMIOAddress(0xC0000000, is_wii));

  // Effective address of an MMIO register; MMIO only deals with physical
  // addresses.
  EXPECT_FALSE(MMIO::IsMMIOAddress(0xCC0000E0, is_wii));

  // And let's check some valid addresses too
  EXPECT_TRUE(MMIO::IsMMIOAddress(0x0C0000E0, is_wii));  // GameCube MMIOs
  EXPECT_TRUE(MMIO::IsMMIOAddress(0x0D00008C, is_wii));  // Wii MMIOs
  EXPECT_TRUE(MMIO::IsMMIOAddress(0x0D800F10, is_wii));  // Mirror of Wii MMIOs
}

class MappingTest : public testing::Test
{
protected:
  virtual void SetUp() override
  {
    m_system = &Core::System::GetInstance();
    m_mapping = std::make_unique<MMIO::Mapping>();
  }
  virtual void TearDown() override
  {
    m_system = nullptr;
    m_mapping.reset();
  }
  Core::System* m_system = nullptr;
  std::unique_ptr<MMIO::Mapping> m_mapping;
};

TEST_F(MappingTest, ReadConstant)
{
  m_mapping->Register(0x0C001234, MMIO::Constant<u8>(0x42), MMIO::Nop<u8>());
  m_mapping->Register(0x0C001234, MMIO::Constant<u16>(0x1234), MMIO::Nop<u16>());
  m_mapping->Register(0x0C001234, MMIO::Constant<u32>(0xdeadbeef), MMIO::Nop<u32>());

  u8 val8 = m_mapping->Read<u8>(*m_system, 0x0C001234);
  u16 val16 = m_mapping->Read<u16>(*m_system, 0x0C001234);
  u32 val32 = m_mapping->Read<u32>(*m_system, 0x0C001234);

  EXPECT_EQ(0x42, val8);
  EXPECT_EQ(0x1234, val16);
  EXPECT_EQ(0xdeadbeef, val32);
}

TEST_F(MappingTest, ReadWriteDirect)
{
  u8 target_8 = 0;
  u16 target_16 = 0;
  u32 target_32 = 0;

  m_mapping->Register(0x0C001234, MMIO::DirectRead<u8>(&target_8),
                      MMIO::DirectWrite<u8>(&target_8));
  m_mapping->Register(0x0C001234, MMIO::DirectRead<u16>(&target_16),
                      MMIO::DirectWrite<u16>(&target_16));
  m_mapping->Register(0x0C001234, MMIO::DirectRead<u32>(&target_32),
                      MMIO::DirectWrite<u32>(&target_32));

  for (u32 i = 0; i < 100; ++i)
  {
    u8 val8 = m_mapping->Read<u8>(*m_system, 0x0C001234);
    EXPECT_EQ(i, val8);
    u16 val16 = m_mapping->Read<u16>(*m_system, 0x0C001234);
    EXPECT_EQ(i, val16);
    u32 val32 = m_mapping->Read<u32>(*m_system, 0x0C001234);
    EXPECT_EQ(i, val32);

    val8 += 1;
    m_mapping->Write(*m_system, 0x0C001234, val8);
    val16 += 1;
    m_mapping->Write(*m_system, 0x0C001234, val16);
    val32 += 1;
    m_mapping->Write(*m_system, 0x0C001234, val32);
  }
}

TEST_F(MappingTest, ReadWriteComplex)
{
  bool read_called = false, write_called = false;

  m_mapping->Register(0x0C001234, MMIO::ComplexRead<u8>([&read_called](Core::System&, u32 addr) {
                        EXPECT_EQ(0x0C001234u, addr);
                        read_called = true;
                        return 0x12;
                      }),
                      MMIO::ComplexWrite<u8>([&write_called](Core::System&, u32 addr, u8 val) {
                        EXPECT_EQ(0x0C001234u, addr);
                        EXPECT_EQ(0x34, val);
                        write_called = true;
                      }));

  u8 val = m_mapping->Read<u8>(*m_system, 0x0C001234);
  EXPECT_EQ(0x12, val);
  m_mapping->Write(*m_system, 0x0C001234, (u8)0x34);

  EXPECT_TRUE(read_called);
  EXPECT_TRUE(write_called);
}