// SPDX-FileCopyrightText: Copyright 2018 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later

#include <utility>

#include "core/core.h"
#include "core/file_sys/content_archive.h"
#include "core/file_sys/nca_metadata.h"
#include "core/file_sys/registered_cache.h"
#include "core/file_sys/romfs_factory.h"
#include "core/hle/kernel/k_process.h"
#include "core/hle/service/filesystem/filesystem.h"
#include "core/loader/deconstructed_rom_directory.h"
#include "core/loader/nca.h"

namespace Loader {

AppLoader_NCA::AppLoader_NCA(FileSys::VirtualFile file_)
    : AppLoader(std::move(file_)), nca(std::make_unique<FileSys::NCA>(file)) {}

AppLoader_NCA::~AppLoader_NCA() = default;

FileType AppLoader_NCA::IdentifyType(const FileSys::VirtualFile& nca_file) {
    const FileSys::NCA nca(nca_file);

    if (nca.GetStatus() == ResultStatus::Success &&
        nca.GetType() == FileSys::NCAContentType::Program) {
        return FileType::NCA;
    }

    return FileType::Error;
}

AppLoader_NCA::LoadResult AppLoader_NCA::Load(Kernel::KProcess& process, Core::System& system) {
    if (is_loaded) {
        return {ResultStatus::ErrorAlreadyLoaded, {}};
    }

    const auto result = nca->GetStatus();
    if (result != ResultStatus::Success) {
        return {result, {}};
    }

    if (nca->GetType() != FileSys::NCAContentType::Program) {
        return {ResultStatus::ErrorNCANotProgram, {}};
    }

    auto exefs = nca->GetExeFS();
    if (exefs == nullptr) {
        LOG_INFO(Loader, "No ExeFS found in NCA, looking for ExeFS from update");

        // This NCA may be a sparse base of an installed title.
        // Try to fetch the ExeFS from the installed update.
        const auto& installed = system.GetContentProvider();
        const auto update_nca = installed.GetEntry(FileSys::GetUpdateTitleID(nca->GetTitleId()),
                                                   FileSys::ContentRecordType::Program);

        if (update_nca) {
            exefs = update_nca->GetExeFS();
        }

        if (exefs == nullptr) {
            return {ResultStatus::ErrorNoExeFS, {}};
        }
    }

    directory_loader = std::make_unique<AppLoader_DeconstructedRomDirectory>(exefs, true);

    const auto load_result = directory_loader->Load(process, system);
    if (load_result.first != ResultStatus::Success) {
        return load_result;
    }

    if (nca->GetRomFS() != nullptr && nca->GetRomFS()->GetSize() > 0) {
        system.GetFileSystemController().RegisterRomFS(std::make_unique<FileSys::RomFSFactory>(
            *this, system.GetContentProvider(), system.GetFileSystemController()));
    }

    is_loaded = true;
    return load_result;
}

ResultStatus AppLoader_NCA::ReadRomFS(FileSys::VirtualFile& dir) {
    if (nca == nullptr) {
        return ResultStatus::ErrorNotInitialized;
    }

    if (nca->GetRomFS() == nullptr || nca->GetRomFS()->GetSize() == 0) {
        return ResultStatus::ErrorNoRomFS;
    }

    dir = nca->GetRomFS();
    return ResultStatus::Success;
}

ResultStatus AppLoader_NCA::ReadProgramId(u64& out_program_id) {
    if (nca == nullptr || nca->GetStatus() != ResultStatus::Success) {
        return ResultStatus::ErrorNotInitialized;
    }

    out_program_id = nca->GetTitleId();
    return ResultStatus::Success;
}

ResultStatus AppLoader_NCA::ReadBanner(std::vector<u8>& buffer) {
    if (nca == nullptr || nca->GetStatus() != ResultStatus::Success) {
        return ResultStatus::ErrorNotInitialized;
    }

    const auto logo = nca->GetLogoPartition();
    if (logo == nullptr) {
        return ResultStatus::ErrorNoIcon;
    }

    buffer = logo->GetFile("StartupMovie.gif")->ReadAllBytes();
    return ResultStatus::Success;
}

ResultStatus AppLoader_NCA::ReadLogo(std::vector<u8>& buffer) {
    if (nca == nullptr || nca->GetStatus() != ResultStatus::Success) {
        return ResultStatus::ErrorNotInitialized;
    }

    const auto logo = nca->GetLogoPartition();
    if (logo == nullptr) {
        return ResultStatus::ErrorNoIcon;
    }

    buffer = logo->GetFile("NintendoLogo.png")->ReadAllBytes();
    return ResultStatus::Success;
}

ResultStatus AppLoader_NCA::ReadNSOModules(Modules& modules) {
    if (directory_loader == nullptr) {
        return ResultStatus::ErrorNotInitialized;
    }

    return directory_loader->ReadNSOModules(modules);
}

} // namespace Loader