/* Copyright (C) 2019 Mr Goldberg
   This file is part of the Goldberg Emulator

   The Goldberg Emulator is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 3 of the License, or (at your option) any later version.

   The Goldberg Emulator is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the Goldberg Emulator; if not, see
   <http://www.gnu.org/licenses/>.  */

#include "steam_user_stats.h"
#include "dll.h"

unsigned int Steam_User_Stats::find_leaderboard(std::string name)
{
    unsigned index = 1;
    for (auto& leaderboard : leaderboards) {
        if (leaderboard.name == name) return index;
        ++index;
    }

    return 0;
}

void Steam_User_Stats::load_achievements_db()
{
    std::string file_path = Local_Storage::get_game_settings_path() + achievements_user_file;
    local_storage->load_json(file_path, defined_achievements);
}

void Steam_User_Stats::load_achievements()
{
    local_storage->load_json_file("", achievements_user_file, user_achievements);
}

void Steam_User_Stats::save_achievements()
{
    local_storage->write_json_file("", achievements_user_file, user_achievements);
}

Steam_User_Stats::Steam_User_Stats(Settings *settings, Local_Storage *local_storage, class SteamCallResults *callback_results, class SteamCallBacks *callbacks):
    settings(settings),
    local_storage(local_storage),
    callback_results(callback_results),
    callbacks(callbacks),
    defined_achievements(nlohmann::json::object()),
    user_achievements(nlohmann::json::object())
{
    load_achievements_db(); // achievements db
    load_achievements(); // achievements per user
}

nlohmann::json const& Steam_User_Stats::GetAchievementsDb() const
{
    return defined_achievements;
}

// Ask the server to send down this user's data and achievements for this game
STEAM_CALL_BACK(UserStatsReceived_t)
bool Steam_User_Stats::RequestCurrentStats()
{
    PRINT_DEBUG("Steam_User_Stats::RequestCurrentStats\n");
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    UserStatsReceived_t data;
    data.m_nGameID = settings->get_local_game_id().ToUint64();
    data.m_eResult = k_EResultOK;
    data.m_steamIDUser = settings->get_local_steam_id();
    callbacks->addCBResult(data.k_iCallback, &data, sizeof(data), 0.1);
    return true;
}


// Data accessors
bool Steam_User_Stats::GetStat(const char* pchName, int32* pData)
{
    PRINT_DEBUG("GetStat int32 %s\n", pchName);
    if (!pchName || !pData) return false;
    std::lock_guard<std::recursive_mutex> lock(global_mutex);
    auto stats_config = settings->getStats();
    auto stats_data = stats_config.find(pchName);
    if (stats_data != stats_config.end()) {
        if (stats_data->second.type != Stat_Type::STAT_TYPE_INT) return false;
    }

    int read_data = local_storage->get_data(Local_Storage::stats_storage_folder, pchName, (char*)pData, sizeof(*pData));
    if (read_data == sizeof(int32))
        return true;

    if (stats_data != stats_config.end()) {
        *pData = stats_data->second.default_value_int;
        return true;
    }

    return false;
}

bool Steam_User_Stats::GetStat(const char* pchName, float* pData)
{
    PRINT_DEBUG("GetStat float %s\n", pchName);
    if (!pchName || !pData) return false;
    std::lock_guard<std::recursive_mutex> lock(global_mutex);
    auto stats_config = settings->getStats();
    auto stats_data = stats_config.find(pchName);
    if (stats_data != stats_config.end()) {
        if (stats_data->second.type == Stat_Type::STAT_TYPE_INT) return false;
    }

    int read_data = local_storage->get_data(Local_Storage::stats_storage_folder, pchName, (char*)pData, sizeof(*pData));
    if (read_data == sizeof(float))
        return true;

    if (stats_data != stats_config.end()) {
        *pData = stats_data->second.default_value_float;
        return true;
    }

    return false;
}


// Set / update data
bool Steam_User_Stats::SetStat(const char* pchName, int32 nData)
{
    PRINT_DEBUG("SetStat int32 %s\n", pchName);
    if (!pchName) return false;
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    return local_storage->store_data(Local_Storage::stats_storage_folder, pchName, (char*)&nData, sizeof(nData)) == sizeof(nData);
}

bool Steam_User_Stats::SetStat(const char* pchName, float fData)
{
    PRINT_DEBUG("SetStat float %s\n", pchName);
    if (!pchName) return false;
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    return local_storage->store_data(Local_Storage::stats_storage_folder, pchName, (char*)&fData, sizeof(fData)) == sizeof(fData);
}

bool Steam_User_Stats::UpdateAvgRateStat(const char* pchName, float flCountThisSession, double dSessionLength)
{
    PRINT_DEBUG("UpdateAvgRateStat %s\n", pchName);
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    char data[sizeof(float) + sizeof(float) + sizeof(double)];
    int read_data = local_storage->get_data(Local_Storage::stats_storage_folder, pchName, (char*)data, sizeof(*data));
    float oldcount = 0;
    double oldsessionlength = 0;
    if (read_data == sizeof(data)) {
        memcpy(&oldcount, data + sizeof(float), sizeof(oldcount));
        memcpy(&oldsessionlength, data + sizeof(float) + sizeof(double), sizeof(oldsessionlength));
    }

    oldcount += flCountThisSession;
    oldsessionlength += dSessionLength;

    float average = oldcount / oldsessionlength;
    memcpy(data, &average, sizeof(average));
    memcpy(data + sizeof(float), &oldcount, sizeof(oldcount));
    memcpy(data + sizeof(float) * 2, &oldsessionlength, sizeof(oldsessionlength));

    return local_storage->store_data(Local_Storage::stats_storage_folder, pchName, data, sizeof(data)) == sizeof(data);
}


// Achievement flag accessors
bool Steam_User_Stats::GetAchievement(const char* pchName, bool* pbAchieved)
{
    PRINT_DEBUG("GetAchievement %s\n", pchName);
    if (pchName == nullptr) return false;
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    try {
        auto it = std::find_if(defined_achievements.begin(), defined_achievements.end(), [pchName](nlohmann::json& item) {
            return item["name"].get<std::string>() == pchName;
            });
        auto ach = user_achievements.find(pchName);
        if (it != defined_achievements.end() && ach != user_achievements.end()) {
            if (pbAchieved != nullptr) *pbAchieved = (*ach)["earned"];
            return true;
        }
    }
    catch (...) {}

    if (pbAchieved != nullptr)*pbAchieved = false;

    return false;
}

bool Steam_User_Stats::SetAchievement(const char* pchName)
{
    PRINT_DEBUG("SetAchievement %s\n", pchName);
    if (pchName == nullptr) return false;

    try {
        auto it = std::find_if(defined_achievements.begin(), defined_achievements.end(), [pchName](nlohmann::json& item) {
            return item["name"].get<std::string>() == pchName;
            });
        if (it != defined_achievements.end()) {
            if (user_achievements.find(pchName) == user_achievements.end() || user_achievements[pchName].value("earned", false) == false) {
                user_achievements[pchName]["earned"] = true;
                user_achievements[pchName]["earned_time"] = std::chrono::duration_cast<std::chrono::duration<uint32>>(std::chrono::system_clock::now().time_since_epoch()).count();
#ifndef NO_OVERLAY
                get_steam_client()->steam_overlay->AddAchievementNotification(it.value());
#endif
            }
            return true;
        }
    }
    catch (...) {}

    return false;
}

bool Steam_User_Stats::ClearAchievement(const char* pchName)
{
    PRINT_DEBUG("ClearAchievement %s\n", pchName);
    if (pchName == nullptr) return false;
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    try {
        auto it = std::find_if(defined_achievements.begin(), defined_achievements.end(), [pchName](nlohmann::json& item) {
            return static_cast<std::string const&>(item["name"]) == pchName;
            });
        if (it != defined_achievements.end()) {
            user_achievements[pchName]["earned"] = false;
            user_achievements[pchName]["earned_time"] = static_cast<uint32>(0);
            return true;
        }
    }
    catch (...) {}

    return false;
}


// Get the achievement status, and the time it was unlocked if unlocked.
// If the return value is true, but the unlock time is zero, that means it was unlocked before Steam 
// began tracking achievement unlock times (December 2009). Time is seconds since January 1, 1970.
bool Steam_User_Stats::GetAchievementAndUnlockTime(const char* pchName, bool* pbAchieved, uint32* punUnlockTime)
{
    PRINT_DEBUG("GetAchievementAndUnlockTime\n");
    if (pchName == nullptr) return false;
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    try {
        auto it = std::find_if(defined_achievements.begin(), defined_achievements.end(), [pchName](nlohmann::json& item) {
            return static_cast<std::string const&>(item["name"]) == pchName;
            });
        auto ach = user_achievements.find(pchName);
        if (it != defined_achievements.end() && ach != user_achievements.end()) {
            if (pbAchieved != nullptr) *pbAchieved = (*ach)["earned"];
            if (punUnlockTime != nullptr) *punUnlockTime = (*ach)["earned_time"];
            return true;
        }
    }
    catch (...) {}

    if (pbAchieved != nullptr) *pbAchieved = false;
    if (punUnlockTime != nullptr) *punUnlockTime = 0;
    return true;
}


// Store the current data on the server, will get a callback when set
// And one callback for every new achievement
//
// If the callback has a result of k_EResultInvalidParam, one or more stats 
// uploaded has been rejected, either because they broke constraints
// or were out of date. In this case the server sends back updated values.
// The stats should be re-iterated to keep in sync.
bool Steam_User_Stats::StoreStats()
{
    PRINT_DEBUG("StoreStats\n");
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    save_achievements();

    UserStatsStored_t data;
    data.m_nGameID = settings->get_local_game_id().ToUint64();
    data.m_eResult = k_EResultOK;
    callbacks->addCBResult(data.k_iCallback, &data, sizeof(data));
    return true;
}


// Achievement / GroupAchievement metadata

// Gets the icon of the achievement, which is a handle to be used in ISteamUtils::GetImageRGBA(), or 0 if none set. 
// A return value of 0 may indicate we are still fetching data, and you can wait for the UserAchievementIconFetched_t callback
// which will notify you when the bits are ready. If the callback still returns zero, then there is no image set for the
// specified achievement.
int Steam_User_Stats::GetAchievementIcon(const char* pchName)
{
    PRINT_DEBUG("GetAchievementIcon\n");
    if (pchName == nullptr) return 0;
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    return 0;
}


// Get general attributes for an achievement. Accepts the following keys:
// - "name" and "desc" for retrieving the localized achievement name and description (returned in UTF8)
// - "hidden" for retrieving if an achievement is hidden (returns "0" when not hidden, "1" when hidden)
const char* Steam_User_Stats::GetAchievementDisplayAttribute(const char* pchName, const char* pchKey)
{
    PRINT_DEBUG("GetAchievementDisplayAttribute %s %s\n", pchName, pchKey);
    if (pchName == nullptr) return "";
    if (pchKey == nullptr) return "";

    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    if (strcmp (pchKey, "name") == 0) {
        try {
            auto it = std::find_if(defined_achievements.begin(), defined_achievements.end(), [pchName](nlohmann::json& item) {
                return static_cast<std::string const&>(item["name"]) == pchName;
                });
            if (it != defined_achievements.end()) {
                return it.value()["displayName"].get_ptr<std::string*>()->c_str();
            }
        }
        catch (...) {}
    }

    if (strcmp(pchKey, "desc") == 0) {
        try {
            auto it = std::find_if(defined_achievements.begin(), defined_achievements.end(), [pchName](nlohmann::json& item) {
                return static_cast<std::string const&>(item["name"]) == pchName;
                });
            if (it != defined_achievements.end()) {
                return it.value()["description"].get_ptr<std::string*>()->c_str();
            }
        }
        catch (...) {}
    }

    if (strcmp(pchKey, "hidden") == 0) {
        try {
            auto it = std::find_if(defined_achievements.begin(), defined_achievements.end(), [pchName](nlohmann::json& item) {
                return static_cast<std::string const&>(item["name"]) == pchName;
                });
            if (it != defined_achievements.end()) {
                return it.value()["hidden"].get_ptr<std::string*>()->c_str();
            }
        }
        catch (...) {}
    }

    return "";
}


// Achievement progress - triggers an AchievementProgress callback, that is all.
// Calling this w/ N out of N progress will NOT set the achievement, the game must still do that.
bool Steam_User_Stats::IndicateAchievementProgress(const char* pchName, uint32 nCurProgress, uint32 nMaxProgress)
{
    PRINT_DEBUG("IndicateAchievementProgress\n");
    if (pchName == nullptr) return false;
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    try {
        auto it = std::find_if(defined_achievements.begin(), defined_achievements.end(), [pchName](nlohmann::json& item) {
            return static_cast<std::string const&>(item["name"]) == pchName;
        });
        auto ach = user_achievements.find(pchName);
        if (it != defined_achievements.end()) {
            bool achieved = false;
            if (ach != user_achievements.end()) {
                bool achieved = ach->value("earned", false);
            }

            UserAchievementStored_t data = {};
            data.m_nGameID = settings->get_local_game_id().ToUint64();
            data.m_bGroupAchievement = false;
            strncpy(data.m_rgchAchievementName, pchName, k_cchStatNameMax);

            if (achieved) {
                data.m_nCurProgress = 0;
                data.m_nMaxProgress = 0;
            }
            else {
                user_achievements[pchName]["progress"] = nCurProgress;
                user_achievements[pchName]["max_progress"] = nMaxProgress;
                data.m_nCurProgress = nCurProgress;
                data.m_nMaxProgress = nMaxProgress;
            }

            save_achievements();
            callback_results->addCallResult(data.k_iCallback, &data, sizeof(data));
            return true;
        }
    }
    catch (...) {}

    return false;
}


// Used for iterating achievements. In general games should not need these functions because they should have a
// list of existing achievements compiled into them
uint32 Steam_User_Stats::GetNumAchievements()
{
    PRINT_DEBUG("GetNumAchievements\n");
    std::lock_guard<std::recursive_mutex> lock(global_mutex);
    return defined_achievements.size();
}

// Get achievement name iAchievement in [0,GetNumAchievements)
const char* Steam_User_Stats::GetAchievementName(uint32 iAchievement)
{
    PRINT_DEBUG("GetAchievementName\n");
    try {
        static std::string achievement_name;
        achievement_name = defined_achievements[iAchievement]["name"].get<std::string>();
        return achievement_name.c_str();
    }
    catch (...) {}
    return "";
}


// Friends stats & achievements

// downloads stats for the user
// returns a UserStatsReceived_t received when completed
// if the other user has no stats, UserStatsReceived_t.m_eResult will be set to k_EResultFail
// these stats won't be auto-updated; you'll need to call RequestUserStats() again to refresh any data
STEAM_CALL_RESULT(UserStatsReceived_t)
SteamAPICall_t Steam_User_Stats::RequestUserStats(CSteamID steamIDUser)
{
    PRINT_DEBUG("Steam_User_Stats::RequestUserStats %llu\n", steamIDUser.ConvertToUint64());
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    // Enable this to allow hot reload achievements status
    //if (steamIDUser == settings->get_local_steam_id()) {
    //    load_achievements();
    //}


    UserStatsReceived_t data;
    data.m_nGameID = settings->get_local_game_id().ToUint64();
    data.m_eResult = k_EResultOK;
    data.m_steamIDUser = steamIDUser;
    return callback_results->addCallResult(data.k_iCallback, &data, sizeof(data), 0.1);
}


// requests stat information for a user, usable after a successful call to RequestUserStats()
bool Steam_User_Stats::GetUserStat(CSteamID steamIDUser, const char* pchName, int32* pData)
{
    PRINT_DEBUG("GetUserStat %s %llu\n", pchName, steamIDUser.ConvertToUint64());
    if (pchName == nullptr) return false;

    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    if (steamIDUser == settings->get_local_steam_id()) {
        GetStat(pchName, pData);
    }
    else {
        *pData = 0;
    }

    return true;
}

bool Steam_User_Stats::GetUserStat(CSteamID steamIDUser, const char* pchName, float* pData)
{
    PRINT_DEBUG("GetUserStat %s %llu\n", pchName, steamIDUser.ConvertToUint64());
    if (pchName == nullptr) return false;

    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    if (steamIDUser == settings->get_local_steam_id()) {
        GetStat(pchName, pData);
    }
    else {
        *pData = 0;
    }

    return true;
}

bool Steam_User_Stats::GetUserAchievement(CSteamID steamIDUser, const char* pchName, bool* pbAchieved)
{
    PRINT_DEBUG("GetUserAchievement %s\n", pchName);
    if (pchName == nullptr) return false;
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    if (steamIDUser == settings->get_local_steam_id()) {
        return GetAchievement(pchName, pbAchieved);
    }

    return false;
}

// See notes for GetAchievementAndUnlockTime above
bool Steam_User_Stats::GetUserAchievementAndUnlockTime(CSteamID steamIDUser, const char* pchName, bool* pbAchieved, uint32* punUnlockTime)
{
    PRINT_DEBUG("GetUserAchievementAndUnlockTime %s\n", pchName);
    if (pchName == nullptr) return false;
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    if (steamIDUser == settings->get_local_steam_id()) {
        return GetAchievementAndUnlockTime(pchName, pbAchieved, punUnlockTime);
    }
    return false;
}


// Reset stats 
bool Steam_User_Stats::ResetAllStats(bool bAchievementsToo)
{
    PRINT_DEBUG("ResetAllStats\n");
    std::lock_guard<std::recursive_mutex> lock(global_mutex);
    //TODO
    if (bAchievementsToo) {
        std::for_each(user_achievements.begin(), user_achievements.end(), [](nlohmann::json& v) {
            v["earned"] = false;
            v["earned_time"] = 0;
            });
    }

    return true;
}


// Leaderboard functions

// asks the Steam back-end for a leaderboard by name, and will create it if it's not yet
// This call is asynchronous, with the result returned in LeaderboardFindResult_t
STEAM_CALL_RESULT(LeaderboardFindResult_t)
SteamAPICall_t Steam_User_Stats::FindOrCreateLeaderboard(const char* pchLeaderboardName, ELeaderboardSortMethod eLeaderboardSortMethod, ELeaderboardDisplayType eLeaderboardDisplayType)
{
    PRINT_DEBUG("FindOrCreateLeaderboard %s\n", pchLeaderboardName);
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    unsigned int leader = find_leaderboard(pchLeaderboardName);
    if (!leader) {
        struct Steam_Leaderboard leaderboard;
        leaderboard.name = std::string(pchLeaderboardName);
        leaderboard.sort_method = eLeaderboardSortMethod;
        leaderboard.display_type = eLeaderboardDisplayType;
        leaderboards.push_back(leaderboard);
        leader = leaderboards.size();
    }

    LeaderboardFindResult_t data;
    data.m_hSteamLeaderboard = leader;
    data.m_bLeaderboardFound = 1;
    return callback_results->addCallResult(data.k_iCallback, &data, sizeof(data));
}


// as above, but won't create the leaderboard if it's not found
// This call is asynchronous, with the result returned in LeaderboardFindResult_t
STEAM_CALL_RESULT(LeaderboardFindResult_t)
SteamAPICall_t Steam_User_Stats::FindLeaderboard(const char* pchLeaderboardName)
{
    PRINT_DEBUG("FindLeaderboard %s\n", pchLeaderboardName);
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    auto settings_Leaderboards = settings->getLeaderboards();
    if (settings_Leaderboards.count(pchLeaderboardName)) {
        auto config = settings_Leaderboards[pchLeaderboardName];
        return FindOrCreateLeaderboard(pchLeaderboardName, config.sort_method, config.display_type);
    }
    else if (settings->createUnknownLeaderboards()) {
        return FindOrCreateLeaderboard(pchLeaderboardName, k_ELeaderboardSortMethodDescending, k_ELeaderboardDisplayTypeNumeric);
    }
    else {
        LeaderboardFindResult_t data;
        data.m_hSteamLeaderboard = find_leaderboard(pchLeaderboardName);;
        data.m_bLeaderboardFound = !!data.m_hSteamLeaderboard;
        return callback_results->addCallResult(data.k_iCallback, &data, sizeof(data));
    }
}


// returns the name of a leaderboard
const char* Steam_User_Stats::GetLeaderboardName(SteamLeaderboard_t hSteamLeaderboard)
{
    PRINT_DEBUG("GetLeaderboardName\n");
    std::lock_guard<std::recursive_mutex> lock(global_mutex);

    if (hSteamLeaderboard > leaderboards.size() || hSteamLeaderboard <= 0) return "";
    return leaderboards[hSteamLeaderboard - 1].name.c_str();
}


// returns the total number of entries in a leaderboard, as of the last request
int Steam_User_Stats::GetLeaderboardEntryCount(SteamLeaderboard_t hSteamLeaderboard)
{
    PRINT_DEBUG("GetLeaderboardEntryCount\n");
    return 0;
}


// returns the sort method of the leaderboard
ELeaderboardSortMethod Steam_User_Stats::GetLeaderboardSortMethod(SteamLeaderboard_t hSteamLeaderboard)
{
    PRINT_DEBUG("GetLeaderboardSortMethod\n");
    std::lock_guard<std::recursive_mutex> lock(global_mutex);
    if (hSteamLeaderboard > leaderboards.size() || hSteamLeaderboard <= 0) return k_ELeaderboardSortMethodNone;
    return leaderboards[hSteamLeaderboard - 1].sort_method;
}


// returns the display type of the leaderboard
ELeaderboardDisplayType Steam_User_Stats::GetLeaderboardDisplayType(SteamLeaderboard_t hSteamLeaderboard)
{
    PRINT_DEBUG("GetLeaderboardDisplayType\n");
    std::lock_guard<std::recursive_mutex> lock(global_mutex);
    if (hSteamLeaderboard > leaderboards.size() || hSteamLeaderboard <= 0) return k_ELeaderboardDisplayTypeNone;
    return leaderboards[hSteamLeaderboard - 1].display_type;
}


// Asks the Steam back-end for a set of rows in the leaderboard.
// This call is asynchronous, with the result returned in LeaderboardScoresDownloaded_t
// LeaderboardScoresDownloaded_t will contain a handle to pull the results from GetDownloadedLeaderboardEntries() (below)
// You can ask for more entries than exist, and it will return as many as do exist.
// k_ELeaderboardDataRequestGlobal requests rows in the leaderboard from the full table, with nRangeStart & nRangeEnd in the range [1, TotalEntries]
// k_ELeaderboardDataRequestGlobalAroundUser requests rows around the current user, nRangeStart being negate
//   e.g. DownloadLeaderboardEntries( hLeaderboard, k_ELeaderboardDataRequestGlobalAroundUser, -3, 3 ) will return 7 rows, 3 before the user, 3 after
// k_ELeaderboardDataRequestFriends requests all the rows for friends of the current user 
STEAM_CALL_RESULT(LeaderboardScoresDownloaded_t)
SteamAPICall_t Steam_User_Stats::DownloadLeaderboardEntries(SteamLeaderboard_t hSteamLeaderboard, ELeaderboardDataRequest eLeaderboardDataRequest, int nRangeStart, int nRangeEnd)
{
    PRINT_DEBUG("DownloadLeaderboardEntries %llu %i %i %i\n", hSteamLeaderboard, eLeaderboardDataRequest, nRangeStart, nRangeEnd);
    std::lock_guard<std::recursive_mutex> lock(global_mutex);
    LeaderboardScoresDownloaded_t data;
    data.m_hSteamLeaderboard = hSteamLeaderboard;
    data.m_hSteamLeaderboardEntries = 123;
    data.m_cEntryCount = 0;
    return callback_results->addCallResult(data.k_iCallback, &data, sizeof(data));
}

// as above, but downloads leaderboard entries for an arbitrary set of users - ELeaderboardDataRequest is k_ELeaderboardDataRequestUsers
// if a user doesn't have a leaderboard entry, they won't be included in the result
// a max of 100 users can be downloaded at a time, with only one outstanding call at a time
STEAM_METHOD_DESC(Downloads leaderboard entries for an arbitrary set of users - ELeaderboardDataRequest is k_ELeaderboardDataRequestUsers)
STEAM_CALL_RESULT(LeaderboardScoresDownloaded_t)
SteamAPICall_t Steam_User_Stats::DownloadLeaderboardEntriesForUsers(SteamLeaderboard_t hSteamLeaderboard,
    STEAM_ARRAY_COUNT_D(cUsers, Array of users to retrieve) CSteamID * prgUsers, int cUsers)
{
    PRINT_DEBUG("DownloadLeaderboardEntriesForUsers %i %llu\n", cUsers, cUsers > 0 ? prgUsers[0].ConvertToUint64() : 0);
    std::lock_guard<std::recursive_mutex> lock(global_mutex);
    LeaderboardScoresDownloaded_t data;
    data.m_hSteamLeaderboard = hSteamLeaderboard;
    data.m_hSteamLeaderboardEntries = 123;
    data.m_cEntryCount = 0;
    return callback_results->addCallResult(data.k_iCallback, &data, sizeof(data));
}


// Returns data about a single leaderboard entry
// use a for loop from 0 to LeaderboardScoresDownloaded_t::m_cEntryCount to get all the downloaded entries
// e.g.
//		void OnLeaderboardScoresDownloaded( LeaderboardScoresDownloaded_t *pLeaderboardScoresDownloaded )
//		{
//			for ( int index = 0; index < pLeaderboardScoresDownloaded->m_cEntryCount; index++ )
//			{
//				LeaderboardEntry_t leaderboardEntry;
//				int32 details[3];		// we know this is how many we've stored previously
//				GetDownloadedLeaderboardEntry( pLeaderboardScoresDownloaded->m_hSteamLeaderboardEntries, index, &leaderboardEntry, details, 3 );
//				assert( leaderboardEntry.m_cDetails == 3 );
//				...
//			}
// once you've accessed all the entries, the data will be free'd, and the SteamLeaderboardEntries_t handle will become invalid
bool Steam_User_Stats::GetDownloadedLeaderboardEntry(SteamLeaderboardEntries_t hSteamLeaderboardEntries, int index, LeaderboardEntry_t * pLeaderboardEntry, int32 * pDetails, int cDetailsMax)
{
    PRINT_DEBUG("GetDownloadedLeaderboardEntry\n");
    return false;
}


// Uploads a user score to the Steam back-end.
// This call is asynchronous, with the result returned in LeaderboardScoreUploaded_t
// Details are extra game-defined information regarding how the user got that score
// pScoreDetails points to an array of int32's, cScoreDetailsCount is the number of int32's in the list
STEAM_CALL_RESULT(LeaderboardScoreUploaded_t)
SteamAPICall_t Steam_User_Stats::UploadLeaderboardScore(SteamLeaderboard_t hSteamLeaderboard, ELeaderboardUploadScoreMethod eLeaderboardUploadScoreMethod, int32 nScore, const int32 * pScoreDetails, int cScoreDetailsCount)
{
    PRINT_DEBUG("UploadLeaderboardScore\n");
    std::lock_guard<std::recursive_mutex> lock(global_mutex);
    LeaderboardScoreUploaded_t data;
    data.m_bSuccess = 1; //needs to be success or DOA6 freezes when uploading score.
    //data.m_bSuccess = 0;
    data.m_hSteamLeaderboard = hSteamLeaderboard;
    data.m_nScore = nScore;
    //data.m_bScoreChanged = 1;
    data.m_bScoreChanged = 0;
    //data.m_nGlobalRankNew = 1;
    data.m_nGlobalRankNew = 0;
    data.m_nGlobalRankPrevious = 0;
    return callback_results->addCallResult(data.k_iCallback, &data, sizeof(data));
}

SteamAPICall_t Steam_User_Stats::UploadLeaderboardScore(SteamLeaderboard_t hSteamLeaderboard, int32 nScore, int32 * pScoreDetails, int cScoreDetailsCount)
{
    PRINT_DEBUG("UploadLeaderboardScore old\n");
    return UploadLeaderboardScore(hSteamLeaderboard, k_ELeaderboardUploadScoreMethodKeepBest, nScore, pScoreDetails, cScoreDetailsCount);
}


// Attaches a piece of user generated content the user's entry on a leaderboard.
// hContent is a handle to a piece of user generated content that was shared using ISteamUserRemoteStorage::FileShare().
// This call is asynchronous, with the result returned in LeaderboardUGCSet_t.
STEAM_CALL_RESULT(LeaderboardUGCSet_t)
SteamAPICall_t Steam_User_Stats::AttachLeaderboardUGC(SteamLeaderboard_t hSteamLeaderboard, UGCHandle_t hUGC)
{
    PRINT_DEBUG("AttachLeaderboardUGC\n");
    std::lock_guard<std::recursive_mutex> lock(global_mutex);
    LeaderboardUGCSet_t data = {};
    if (hSteamLeaderboard > leaderboards.size() || hSteamLeaderboard <= 0) {
        data.m_eResult = k_EResultFail;
    }
    else {
        data.m_eResult = k_EResultOK;
    }

    data.m_hSteamLeaderboard = hSteamLeaderboard;
    return callback_results->addCallResult(data.k_iCallback, &data, sizeof(data));
}


// Retrieves the number of players currently playing your game (online + offline)
// This call is asynchronous, with the result returned in NumberOfCurrentPlayers_t
STEAM_CALL_RESULT(NumberOfCurrentPlayers_t)
SteamAPICall_t Steam_User_Stats::GetNumberOfCurrentPlayers()
{
    PRINT_DEBUG("GetNumberOfCurrentPlayers\n");
    std::lock_guard<std::recursive_mutex> lock(global_mutex);
    NumberOfCurrentPlayers_t data;
    data.m_bSuccess = 1;
    data.m_cPlayers = 69;
    return callback_results->addCallResult(data.k_iCallback, &data, sizeof(data));
}


// Requests that Steam fetch data on the percentage of players who have received each achievement
// for the game globally.
// This call is asynchronous, with the result returned in GlobalAchievementPercentagesReady_t.
STEAM_CALL_RESULT(GlobalAchievementPercentagesReady_t)
SteamAPICall_t Steam_User_Stats::RequestGlobalAchievementPercentages()
{
    PRINT_DEBUG("RequestGlobalAchievementPercentages\n");
}


// Get the info on the most achieved achievement for the game, returns an iterator index you can use to fetch
// the next most achieved afterwards.  Will return -1 if there is no data on achievement 
// percentages (ie, you haven't called RequestGlobalAchievementPercentages and waited on the callback).
int Steam_User_Stats::GetMostAchievedAchievementInfo(char* pchName, uint32 unNameBufLen, float* pflPercent, bool* pbAchieved)
{
    PRINT_DEBUG("GetMostAchievedAchievementInfo\n");
}


// Get the info on the next most achieved achievement for the game. Call this after GetMostAchievedAchievementInfo or another
// GetNextMostAchievedAchievementInfo call passing the iterator from the previous call. Returns -1 after the last
// achievement has been iterated.
int Steam_User_Stats::GetNextMostAchievedAchievementInfo(int iIteratorPrevious, char* pchName, uint32 unNameBufLen, float* pflPercent, bool* pbAchieved)
{
    PRINT_DEBUG("GetNextMostAchievedAchievementInfo\n");
}


// Returns the percentage of users who have achieved the specified achievement.
bool Steam_User_Stats::GetAchievementAchievedPercent(const char* pchName, float* pflPercent)
{
    PRINT_DEBUG("GetAchievementAchievedPercent\n");
}


// Requests global stats data, which is available for stats marked as "aggregated".
// This call is asynchronous, with the results returned in GlobalStatsReceived_t.
// nHistoryDays specifies how many days of day-by-day history to retrieve in addition
// to the overall totals. The limit is 60.
STEAM_CALL_RESULT(GlobalStatsReceived_t)
SteamAPICall_t Steam_User_Stats::RequestGlobalStats(int nHistoryDays)
{
    PRINT_DEBUG("RequestGlobalStats %i\n", nHistoryDays);
    std::lock_guard<std::recursive_mutex> lock(global_mutex);
    GlobalStatsReceived_t data;
    data.m_nGameID = settings->get_local_game_id().ToUint64();
    data.m_eResult = k_EResultOK;
    return callback_results->addCallResult(data.k_iCallback, &data, sizeof(data));
}


// Gets the lifetime totals for an aggregated stat
bool Steam_User_Stats::GetGlobalStat(const char* pchStatName, int64 * pData)
{
    PRINT_DEBUG("GetGlobalStat %s\n", pchStatName);
    return false;
}

bool Steam_User_Stats::GetGlobalStat(const char* pchStatName, double* pData)
{
    PRINT_DEBUG("GetGlobalStat %s\n", pchStatName);
    return false;
}


// Gets history for an aggregated stat. pData will be filled with daily values, starting with today.
// So when called, pData[0] will be today, pData[1] will be yesterday, and pData[2] will be two days ago, 
// etc. cubData is the size in bytes of the pubData buffer. Returns the number of 
// elements actually set.
int32 Steam_User_Stats::GetGlobalStatHistory(const char* pchStatName, STEAM_ARRAY_COUNT(cubData) int64 * pData, uint32 cubData)
{
    PRINT_DEBUG("GetGlobalStatHistory int64 %s\n", pchStatName);
    return 0;
}

int32 Steam_User_Stats::GetGlobalStatHistory(const char* pchStatName, STEAM_ARRAY_COUNT(cubData) double* pData, uint32 cubData)
{
    PRINT_DEBUG("GetGlobalStatHistory double %s\n", pchStatName);
    return 0;
}