// Copyright (C) 2024-2026 NXST contributors
#include <algorithm>
#include <cstring>
#include <vector>

#include "nxst/domain/account.hpp"
#include <nxst/domain/util.hpp>
#include <nxst/domain/title.hpp>
#include <nxst/domain/util.hpp>
#include <nxst/infra/fs/directory.hpp>
#include <nxst/infra/sys/logger.hpp>

using sort_t = enum { SortAlpha, SortLastPlayed, SortPlayTime, SortModesCount };
static constexpr const char* kEmptySave = "New...";
static sort_t s_sort_mode = SortAlpha;

static std::unordered_map<AccountUid, std::vector<Title>> titles;
static bool s_titles_loaded = false;

void Title::init(u8 save_data_type, u64 title_id, AccountUid uid, const std::string& name,
                 const std::string& author) {
    m_id = title_id;
    m_uid = uid;
    m_save_data_type = save_data_type;
    m_user_name = Account::username(uid);
    m_author = author;
    m_name = name;
    m_safe_name = StringUtils::containsInvalidChar(name) ? StringUtils::format("0x%016llX", m_id)
                                                         : StringUtils::removeForbiddenCharacters(name);
    m_path = "sdmc:/switch/NXST/saves/" + StringUtils::format("0x%016llX", m_id) + " " + m_safe_name;

    std::string aname = StringUtils::removeAccents(m_name);
    m_display_name = {aname, ""};

    size_t colon = aname.rfind(':');
    if (colon != std::string::npos) {
        std::string head = aname.substr(0, colon);
        std::string tail = aname.substr(colon + 1);
        StringUtils::trim(head);
        StringUtils::trim(tail);
        m_display_name = {head, tail};
    } else {
        size_t open = aname.rfind('(');
        size_t close = aname.rfind(')');
        if (open != std::string::npos && close != std::string::npos && close > open) {
            std::string head = aname.substr(0, open);
            std::string paren = aname.substr(open + 1, close - open - 1);
            StringUtils::trim(head);
            StringUtils::trim(paren);
            m_display_name = {head, paren};
        }
    }

    refreshDirectories();
}

u8 Title::saveDataType() const {
    return m_save_data_type;
}
u64 Title::id() const {
    return m_id;
}
u64 Title::saveId() const {
    return m_save_id;
}
void Title::saveId(u64 id) {
    m_save_id = id;
}
AccountUid Title::userId() const {
    return m_uid;
}
std::string Title::userName() const {
    return m_user_name;
}
std::string Title::author() const {
    return m_author;
}
std::string Title::name() const {
    return m_name;
}
std::pair<std::string, std::string> Title::displayName() const {
    return m_display_name;
}
std::string Title::path() const {
    return m_path;
}
std::string Title::fullPath(size_t index) const {
    return m_full_save_paths.at(index);
}
std::vector<std::string> Title::saves() const {
    return m_saves;
}
u64 Title::playTimeNanoseconds() const {
    return m_play_time_ns;
}
void Title::playTimeNanoseconds(u64 ns) {
    m_play_time_ns = ns;
}
u32 Title::lastPlayedTimestamp() const {
    return m_last_played_ts;
}
void Title::lastPlayedTimestamp(u32 ts) {
    m_last_played_ts = ts;
}

std::string Title::playTime() const {
    const u64 minutes = m_play_time_ns / 60000000000ULL;
    return StringUtils::format("%d", minutes / 60) + ":" + StringUtils::format("%02d", minutes % 60) +
           " hours";
}

void Title::refreshDirectories() {
    m_saves.clear();
    m_full_save_paths.clear();

    Directory savelist(m_path);
    if (savelist.good()) {
        for (size_t i = 0; i < savelist.size(); ++i) {
            if (savelist.folder(i)) {
                m_saves.push_back(savelist.entry(i));
                m_full_save_paths.push_back(m_path + "/" + savelist.entry(i));
            }
        }
        std::sort(m_saves.rbegin(), m_saves.rend());
        std::sort(m_full_save_paths.rbegin(), m_full_save_paths.rend());
        m_saves.insert(m_saves.begin(), kEmptySave);
        m_full_save_paths.insert(m_full_save_paths.begin(), kEmptySave);
    } else {
        nxst::log::error("Could not read save directory for title %s", m_name.c_str());
    }
}

bool areTitlesLoaded() {
    return s_titles_loaded;
}

void loadTitles() {
    if (s_titles_loaded)
        return;
    s_titles_loaded = true;
    titles.clear();

    FsSaveDataInfoReader reader;
    Result res = fsOpenSaveDataInfoReader(&reader, FsSaveDataSpaceId_User);
    if (R_FAILED(res))
        return;

    std::vector<u8> nacp_buf(sizeof(NsApplicationControlData), 0);
    auto* nsacd = reinterpret_cast<NsApplicationControlData*>(nacp_buf.data());

    FsSaveDataInfo info{};
    s64 count = 0;
    while (true) {
        res = fsSaveDataInfoReaderRead(&reader, &info, 1, &count);
        if (R_FAILED(res) || count == 0)
            break;
        if (info.save_data_type != FsSaveDataType_Account)
            continue;

        u64 tid = info.application_id;
        AccountUid uid = info.uid;
        size_t outsize = 0;
        NacpLanguageEntry* nle = nullptr;

        memset(nsacd, 0, sizeof(NsApplicationControlData));
        res = nsGetApplicationControlData(NsApplicationControlSource_Storage, tid, nsacd,
                                          sizeof(NsApplicationControlData), &outsize);
        if (R_FAILED(res) || outsize < sizeof(nsacd->nacp))
            continue;
        if (R_FAILED(nacpGetLanguageEntry(&nsacd->nacp, &nle)) || !nle)
            continue;

        Title title;
        title.init(info.save_data_type, tid, uid, std::string(nle->name), std::string(nle->author));
        title.saveId(info.save_data_id);

        PdmPlayStatistics stats{};
        if (R_SUCCEEDED(pdmqryQueryPlayStatisticsByApplicationIdAndUserAccountId(tid, uid, false, &stats))) {
            title.playTimeNanoseconds(stats.playtime);
            title.lastPlayedTimestamp(stats.last_timestamp_user);
        }

        auto it = titles.find(uid);
        if (it != titles.end()) {
            it->second.push_back(title);
        } else {
            titles.emplace(uid, std::vector<Title>{title});
        }
    }

    fsSaveDataInfoReaderClose(&reader);
    sortTitles();
}

void sortTitles() {
    for (auto& pair : titles) {
        std::sort(pair.second.begin(), pair.second.end(), [](const Title& l, const Title& r) {
            switch (s_sort_mode) {
            case SortLastPlayed:
                return l.lastPlayedTimestamp() > r.lastPlayedTimestamp();
            case SortPlayTime:
                return l.playTimeNanoseconds() > r.playTimeNanoseconds();
            case SortAlpha:
            default:
                return l.name() < r.name();
            }
        });
    }
}

void rotateSortMode() {
    s_sort_mode = static_cast<sort_t>((s_sort_mode + 1) % SortModesCount);
    sortTitles();
}

void getTitle(Title& dst, AccountUid uid, size_t i) {
    auto it = titles.find(uid);
    if (it != titles.end() && i < it->second.size())
        dst = it->second[i];
}

size_t getTitleCount(AccountUid uid) {
    auto it = titles.find(uid);
    return it != titles.end() ? it->second.size() : 0;
}

void refreshDirectories(u64 id) {
    for (auto& pair : titles) {
        for (auto& title : pair.second) {
            if (title.id() == id)
                title.refreshDirectories();
        }
    }
}

std::unordered_map<std::string, std::string> getCompleteTitleList() {
    std::unordered_map<std::string, std::string> map;
    for (const auto& pair : titles) {
        for (const auto& title : pair.second) {
            map.emplace(StringUtils::format("0x%016llX", title.id()), title.name());
        }
    }
    return map;
}