// Copyright 2018 yuzu emulator team
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.

#include <memory>
#include <string>
#include <utility>
#include <vector>

#include <QDir>
#include <QFileInfo>

#include "common/common_paths.h"
#include "common/file_util.h"
#include "core/file_sys/content_archive.h"
#include "core/file_sys/control_metadata.h"
#include "core/file_sys/mode.h"
#include "core/file_sys/nca_metadata.h"
#include "core/file_sys/patch_manager.h"
#include "core/file_sys/registered_cache.h"
#include "core/hle/service/filesystem/filesystem.h"
#include "core/loader/loader.h"
#include "yuzu/compatibility_list.h"
#include "yuzu/game_list.h"
#include "yuzu/game_list_p.h"
#include "yuzu/game_list_worker.h"
#include "yuzu/ui_settings.h"

namespace {
void GetMetadataFromControlNCA(const FileSys::PatchManager& patch_manager, const FileSys::NCA& nca,
                               std::vector<u8>& icon, std::string& name) {
    auto [nacp, icon_file] = patch_manager.ParseControlNCA(nca);
    if (icon_file != nullptr)
        icon = icon_file->ReadAllBytes();
    if (nacp != nullptr)
        name = nacp->GetApplicationName();
}

bool HasSupportedFileExtension(const std::string& file_name) {
    const QFileInfo file = QFileInfo(QString::fromStdString(file_name));
    return GameList::supported_file_extensions.contains(file.suffix(), Qt::CaseInsensitive);
}

bool IsExtractedNCAMain(const std::string& file_name) {
    return QFileInfo(QString::fromStdString(file_name)).fileName() == "main";
}

QString FormatGameName(const std::string& physical_name) {
    const QString physical_name_as_qstring = QString::fromStdString(physical_name);
    const QFileInfo file_info(physical_name_as_qstring);

    if (IsExtractedNCAMain(physical_name)) {
        return file_info.dir().path();
    }

    return physical_name_as_qstring;
}

QString FormatPatchNameVersions(const FileSys::PatchManager& patch_manager,
                                Loader::AppLoader& loader, bool updatable = true) {
    QString out;
    FileSys::VirtualFile update_raw;
    loader.ReadUpdateRaw(update_raw);
    for (const auto& kv : patch_manager.GetPatchVersionNames(update_raw)) {
        const bool is_update = kv.first == "Update" || kv.first == "[D] Update";
        if (!updatable && is_update) {
            continue;
        }

        const QString type = QString::fromStdString(kv.first);

        if (kv.second.empty()) {
            out.append(QStringLiteral("%1\n").arg(type));
        } else {
            auto ver = kv.second;

            // Display container name for packed updates
            if (is_update && ver == "PACKED") {
                ver = Loader::GetFileTypeString(loader.GetFileType());
            }

            out.append(QStringLiteral("%1 (%2)\n").arg(type, QString::fromStdString(ver)));
        }
    }

    out.chop(1);
    return out;
}

QList<QStandardItem*> MakeGameListEntry(const std::string& path, const std::string& name,
                                        const std::vector<u8>& icon, Loader::AppLoader& loader,
                                        u64 program_id, const CompatibilityList& compatibility_list,
                                        const FileSys::PatchManager& patch) {
    const auto it = FindMatchingCompatibilityEntry(compatibility_list, program_id);

    // The game list uses this as compatibility number for untested games
    QString compatibility{"99"};
    if (it != compatibility_list.end()) {
        compatibility = it->second.first;
    }

    const auto file_type = loader.GetFileType();
    const auto file_type_string = QString::fromStdString(Loader::GetFileTypeString(file_type));

    QList<QStandardItem*> list{
        new GameListItemPath(FormatGameName(path), icon, QString::fromStdString(name),
                             file_type_string, program_id),
        new GameListItemCompat(compatibility),
        new GameListItem(file_type_string),
        new GameListItemSize(FileUtil::GetSize(path)),
    };

    if (UISettings::values.show_add_ons) {
        list.insert(
            2, new GameListItem(FormatPatchNameVersions(patch, loader, loader.IsRomFSUpdatable())));
    }

    return list;
}
} // Anonymous namespace

GameListWorker::GameListWorker(FileSys::VirtualFilesystem vfs, QString dir_path, bool deep_scan,
                               const CompatibilityList& compatibility_list)
    : vfs(std::move(vfs)), dir_path(std::move(dir_path)), deep_scan(deep_scan),
      compatibility_list(compatibility_list) {}

GameListWorker::~GameListWorker() = default;

void GameListWorker::AddInstalledTitlesToGameList() {
    const auto cache = Service::FileSystem::GetUnionContents();
    const auto installed_games = cache.ListEntriesFilter(FileSys::TitleType::Application,
                                                         FileSys::ContentRecordType::Program);

    for (const auto& game : installed_games) {
        const auto file = cache.GetEntryUnparsed(game);
        std::unique_ptr<Loader::AppLoader> loader = Loader::GetLoader(file);
        if (!loader)
            continue;

        std::vector<u8> icon;
        std::string name;
        u64 program_id = 0;
        loader->ReadProgramId(program_id);

        const FileSys::PatchManager patch{program_id};
        const auto control = cache.GetEntry(game.title_id, FileSys::ContentRecordType::Control);
        if (control != nullptr)
            GetMetadataFromControlNCA(patch, *control, icon, name);

        emit EntryReady(MakeGameListEntry(file->GetFullPath(), name, icon, *loader, program_id,
                                          compatibility_list, patch));
    }

    const auto control_data = cache.ListEntriesFilter(FileSys::TitleType::Application,
                                                      FileSys::ContentRecordType::Control);

    for (const auto& entry : control_data) {
        auto nca = cache.GetEntry(entry);
        if (nca != nullptr) {
            nca_control_map.insert_or_assign(entry.title_id, std::move(nca));
        }
    }
}

void GameListWorker::FillControlMap(const std::string& dir_path) {
    const auto nca_control_callback = [this](u64* num_entries_out, const std::string& directory,
                                             const std::string& virtual_name) -> bool {
        if (stop_processing) {
            // Breaks the callback loop
            return false;
        }

        const std::string physical_name = directory + DIR_SEP + virtual_name;
        const QFileInfo file_info(QString::fromStdString(physical_name));
        if (!file_info.isDir() && file_info.suffix() == QStringLiteral("nca")) {
            auto nca =
                std::make_unique<FileSys::NCA>(vfs->OpenFile(physical_name, FileSys::Mode::Read));
            if (nca->GetType() == FileSys::NCAContentType::Control) {
                const u64 title_id = nca->GetTitleId();
                nca_control_map.insert_or_assign(title_id, std::move(nca));
            }
        }
        return true;
    };

    FileUtil::ForeachDirectoryEntry(nullptr, dir_path, nca_control_callback);
}

void GameListWorker::AddFstEntriesToGameList(const std::string& dir_path, unsigned int recursion) {
    const auto callback = [this, recursion](u64* num_entries_out, const std::string& directory,
                                            const std::string& virtual_name) -> bool {
        if (stop_processing) {
            // Breaks the callback loop.
            return false;
        }

        const std::string physical_name = directory + DIR_SEP + virtual_name;
        const bool is_dir = FileUtil::IsDirectory(physical_name);
        if (!is_dir &&
            (HasSupportedFileExtension(physical_name) || IsExtractedNCAMain(physical_name))) {
            auto loader = Loader::GetLoader(vfs->OpenFile(physical_name, FileSys::Mode::Read));
            if (!loader) {
                return true;
            }

            const auto file_type = loader->GetFileType();
            if ((file_type == Loader::FileType::Unknown || file_type == Loader::FileType::Error) &&
                !UISettings::values.show_unknown) {
                return true;
            }

            std::vector<u8> icon;
            const auto res1 = loader->ReadIcon(icon);

            u64 program_id = 0;
            const auto res2 = loader->ReadProgramId(program_id);

            std::string name = " ";
            const auto res3 = loader->ReadTitle(name);

            const FileSys::PatchManager patch{program_id};

            if (res1 != Loader::ResultStatus::Success && res3 != Loader::ResultStatus::Success &&
                res2 == Loader::ResultStatus::Success) {
                // Use from metadata pool.
                if (nca_control_map.find(program_id) != nca_control_map.end()) {
                    const auto& nca = nca_control_map[program_id];
                    GetMetadataFromControlNCA(patch, *nca, icon, name);
                }
            }

            emit EntryReady(MakeGameListEntry(physical_name, name, icon, *loader, program_id,
                                              compatibility_list, patch));
        } else if (is_dir && recursion > 0) {
            watch_list.append(QString::fromStdString(physical_name));
            AddFstEntriesToGameList(physical_name, recursion - 1);
        }

        return true;
    };

    FileUtil::ForeachDirectoryEntry(nullptr, dir_path, callback);
}

void GameListWorker::run() {
    stop_processing = false;
    watch_list.append(dir_path);
    FillControlMap(dir_path.toStdString());
    AddInstalledTitlesToGameList();
    AddFstEntriesToGameList(dir_path.toStdString(), deep_scan ? 256 : 0);
    nca_control_map.clear();
    emit Finished(watch_list);
}

void GameListWorker::Cancel() {
    this->disconnect();
    stop_processing = true;
}