MesenCE/Core/NES/Loaders/iNesLoader.cpp

#include "pch.h"
#include "NES/Loaders/iNesLoader.h"
#include "Utilities/CRC32.h"
#include "Utilities/HexUtilities.h"
#include "Utilities/StringUtilities.h"
#include "NES/MapperFactory.h"
#include "NES/NesHeader.h"
#include "NES/RomData.h"
#include "NES/GameDatabase.h"
#include "Shared/RomInfo.h"

void iNesLoader::LoadRom(RomData& romData, vector<uint8_t>& romFile, NesHeader* preloadedHeader, bool databaseEnabled)
{
	NesHeader header;
	uint8_t* buffer = romFile.data();
	uint32_t dataSize = (uint32_t)romFile.size();
	if(preloadedHeader) {
		header = *preloadedHeader;
	} else {
		memcpy((char*)&header, buffer, sizeof(NesHeader));
		buffer += sizeof(NesHeader);
		dataSize -= sizeof(NesHeader);
	}

	romData.Info.Format = RomFormat::iNes;

	//NSF header size
	romData.Info.FilePrgOffset = sizeof(NesHeader);

	romData.Info.IsNes20Header = (header.GetRomHeaderVersion() == RomHeaderVersion::Nes2_0);
	romData.Info.MapperID = header.GetMapperID();
	romData.Info.SubMapperID = header.GetSubMapper();
	romData.Info.Mirroring = header.GetMirroringType();
	romData.Info.HasBattery = header.HasBattery();
	romData.Info.HasEpsm = header.HasEpsm();
	romData.Info.System = header.GetGameSystem();
	romData.Info.VsType = header.GetVsSystemType();
	romData.Info.VsPpuModel = header.GetVsSystemPpuModel();
	romData.Info.InputType = header.GetInputType();
	romData.Info.HasTrainer = header.HasTrainer();
	romData.Info.Header = header;

	romData.ChrRamSize = header.GetChrRamSize();
	romData.SaveChrRamSize = header.GetSaveChrRamSize();
	romData.WorkRamSize = header.GetWorkRamSize();
	romData.SaveRamSize = header.GetSaveRamSize();

	if(romData.Info.HasTrainer) {
		if(dataSize >= 512) {
			//512-byte trainer at $7000-$71FF (stored before PRG data)
			romData.TrainerData.insert(romData.TrainerData.end(), buffer, buffer + 512);
			buffer += 512;
			dataSize -= 512;
		} else {
			romData.Error = true;
			MessageManager::Log("[iNes] Invalid file (file length does not match header information) - load operation cancelled.");
			return;
		}
	}

	size_t bytesRead = buffer - romFile.data();

	uint32_t romCrc = CRC32::GetCRC(buffer, romFile.size() - bytesRead);
	romData.Info.Hash.PrgChrCrc32 = romCrc;

	uint32_t prgSize = 0;
	uint32_t chrSize = 0;

	if(!databaseEnabled || romData.Info.IsNes20Header || !GameDatabase::GetDbRomSize(romData.Info.Hash.PrgChrCrc32, prgSize, chrSize)) {
		//Fallback on header sizes when game is not in DB (or DB is disabled)
		prgSize = header.GetPrgSize();
		chrSize = header.GetChrSize();
	}

	if(prgSize == 0) {
		MessageManager::Log("[iNes] Invalid file (PRG size is 0) - load operation cancelled.");
		romData.Error = true;
	}

	if(prgSize + chrSize > dataSize) {
		//Invalid rom file
		MessageManager::Log("[iNes] Invalid file (file length does not match header information) - load operation cancelled.");
		romData.Error = true;
	} else if(prgSize + chrSize < dataSize) {
		MessageManager::Log("[iNes] Warning: File is larger than excepted (based on the file header).");
	}

	if(!romData.Error) {
		romData.Info.Hash.PrgCrc32 = CRC32::GetCRC(buffer, prgSize);

		romData.PrgRom.insert(romData.PrgRom.end(), buffer, buffer + prgSize);
		while(romData.PrgRom.size() < 256) {
			//Ensure the PRG is at least 256 bytes in size by mirroring as needed (mapper code requires it to be 256 bytes at least)
			romData.PrgRom.insert(romData.PrgRom.end(), buffer, buffer + std::min<int>(prgSize, 256 - (int)romData.PrgRom.size()));
		}
		buffer += prgSize;
		romData.ChrRom.insert(romData.ChrRom.end(), buffer, buffer + chrSize);

		Log("PRG CRC32: 0x" + HexUtilities::ToHex(romData.Info.Hash.PrgCrc32, true));
		Log("PRG+CHR CRC32: 0x" + HexUtilities::ToHex(romData.Info.Hash.PrgChrCrc32, true));
	}

	if(romData.Info.IsNes20Header) {
		Log("[iNes] NES 2.0 file: Yes");
	}
	Log("[iNes] Mapper: " + std::to_string(romData.Info.MapperID) + " Sub: " + std::to_string(romData.Info.SubMapperID));

	if(romData.Info.System == GameSystem::VsSystem) {
		string type = "Vs-UniSystem";
		switch(romData.Info.VsType) {
			case VsSystemType::Default: break;
			case VsSystemType::IceClimberProtection: type = "VS-UniSystem (Ice Climbers)"; break;
			case VsSystemType::RaidOnBungelingBayProtection: type = "VS-DualSystem (Raid on Bungeling Bay)"; break;
			case VsSystemType::RbiBaseballProtection: type = "VS-UniSystem (RBI Baseball)"; break;
			case VsSystemType::SuperXeviousProtection: type = "VS-UniSystem (Super Xevious)"; break;
			case VsSystemType::TkoBoxingProtection: type = "VS-UniSystem (TKO Boxing)"; break;
			case VsSystemType::VsDualSystem: type = "VS-DualSystem"; break;
		}
		Log("[iNes] System: " + type);
	}

	Log("[iNes] PRG ROM: " + StringUtilities::SizeToString(prgSize));
	Log("[iNes] CHR ROM: " + StringUtilities::SizeToString(chrSize));
	if(romData.ChrRamSize > 0 || romData.Info.IsNes20Header) {
		Log("[iNes] CHR RAM: " + StringUtilities::SizeToString(romData.ChrRamSize));
	} else if(chrSize == 0) {
		Log("[iNes] CHR RAM: 8 KB");
	}
	if(romData.SaveChrRamSize > 0 || romData.Info.IsNes20Header) {
		Log("[iNes] CHR Save RAM: " + StringUtilities::SizeToString(romData.SaveChrRamSize));
	}
	if(romData.WorkRamSize > 0 || romData.Info.IsNes20Header) {
		Log("[iNes] Work RAM: " + StringUtilities::SizeToString(romData.WorkRamSize));
	}
	if(romData.SaveRamSize > 0 || romData.Info.IsNes20Header) {
		Log("[iNes] Save RAM: " + StringUtilities::SizeToString(romData.SaveRamSize));
	}

	string mirroringType = "";
	switch(romData.Info.Mirroring) {
		case MirroringType::Horizontal: mirroringType = "Horizontal"; break;
		case MirroringType::Vertical: mirroringType = "Vertical"; break;
		case MirroringType::ScreenAOnly: mirroringType = "1-Screen (A)"; break;
		case MirroringType::ScreenBOnly: mirroringType = "1-Screen (B)"; break;
		case MirroringType::FourScreens: mirroringType = "Four Screens"; break;
	}
	Log("[iNes] Mirroring: " + mirroringType);

	Log("[iNes] Battery: " + string(romData.Info.HasBattery ? "Yes" : "No"));
	if(romData.Info.HasTrainer) {
		Log("[iNes] Trainer: Yes");
	}
	if(romData.Info.HasEpsm) {
		Log("[iNes] EPSM: Yes");
	}

	if(!romData.Info.IsNes20Header) {
		GameDatabase::SetGameInfo(romData.Info.Hash.PrgChrCrc32, romData, databaseEnabled, preloadedHeader != nullptr);
	}

	if(romData.Info.System == GameSystem::VsSystem) {
		romData.Info.Format = RomFormat::VsSystem;
		if(romData.Info.VsType == VsSystemType::VsDualSystem) {
			romData.Info.Format = RomFormat::VsDualSystem;
		}
	} else if(romData.Info.System == GameSystem::FamicomNetworkSystem) {
		//temporary code
		romData.Info.MapperID = MapperFactory::FamicomNetworkSystemMapperID;
	}
}