Fix: server menu tooltip shouldn't show language info (#12955)

[openttd-github.git] / src / settings.cpp

/*
 * This file is part of OpenTTD.
 * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
 * OpenTTD 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 General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */

/**
 * @file settings.cpp
 * All actions handling saving and loading of the settings/configuration goes on in this file.
 * The file consists of three parts:
 * <ol>
 * <li>Parsing the configuration file (openttd.cfg). This is achieved with the ini_ functions which
 *     handle various types, such as normal 'key = value' pairs, lists and value combinations of
 *     lists, strings, integers, 'bit'-masks and element selections.
 * <li>Handle reading and writing to the setting-structures from inside the game either from
 *     the console for example or through the gui with CMD_ functions.
 * <li>Handle saving/loading of the PATS chunk inside the savegame.
 * </ol>
 * @see SettingDesc
 * @see SaveLoad
 */

#include "stdafx.h"
#include <charconv>
#include "settings_table.h"
#include "debug.h"
#include "currency.h"
#include "network/network.h"
#include "network/network_func.h"
#include "network/core/config.h"
#include "command_func.h"
#include "console_func.h"
#include "genworld.h"
#include "string_func.h"
#include "window_func.h"
#include "company_func.h"
#include "rev.h"
#include "error.h"
#include "gamelog.h"
#include "settings_func.h"
#include "ini_type.h"
#include "ai/ai_config.hpp"
#include "game/game_config.hpp"
#include "newgrf_config.h"
#include "picker_func.h"
#include "base_media_base.h"
#include "fios.h"
#include "fileio_func.h"
#include "settings_cmd.h"

#include "table/strings.h"

#include "safeguards.h"

ClientSettings _settings_client;
GameSettings _settings_game;     ///< Game settings of a running game or the scenario editor.
GameSettings _settings_newgame;  ///< Game settings for new games (updated from the intro screen).
VehicleDefaultSettings _old_vds; ///< Used for loading default vehicles settings from old savegames.
std::string _config_file; ///< Configuration file of OpenTTD.
std::string _private_file; ///< Private configuration file of OpenTTD.
std::string _secrets_file; ///< Secrets configuration file of OpenTTD.
std::string _favs_file; ///< Picker favourites configuration file of OpenTTD.

static ErrorList _settings_error_list; ///< Errors while loading minimal settings.

/**
 * List of all the generic setting tables.
 *
 * There are a few tables that are special and not processed like the rest:
 * - _currency_settings
 * - _misc_settings
 * - _company_settings
 * - _win32_settings
 * As such, they are not part of this list.
 */
static auto &GenericSettingTables()
{
        static const SettingTable _generic_setting_tables[] = {
                _difficulty_settings,
                _economy_settings,
                _game_settings,
                _gui_settings,
                _linkgraph_settings,
                _locale_settings,
                _multimedia_settings,
                _network_settings,
                _news_display_settings,
                _pathfinding_settings,
                _script_settings,
                _world_settings,
        };
        return _generic_setting_tables;
}

/**
 * List of all the private setting tables.
 */
static auto &PrivateSettingTables()
{
        static const SettingTable _private_setting_tables[] = {
                _network_private_settings,
        };
        return _private_setting_tables;
}

/**
 * List of all the secrets setting tables.
 */
static auto &SecretSettingTables()
{
        static const SettingTable _secrets_setting_tables[] = {
                _network_secrets_settings,
        };
        return _secrets_setting_tables;
}

typedef void SettingDescProc(IniFile &ini, const SettingTable &desc, const char *grpname, void *object, bool only_startup);
typedef void SettingDescProcList(IniFile &ini, const char *grpname, StringList &list);

static bool IsSignedVarMemType(VarType vt)
{
        switch (GetVarMemType(vt)) {
                case SLE_VAR_I8:
                case SLE_VAR_I16:
                case SLE_VAR_I32:
                case SLE_VAR_I64:
                        return true;
        }
        return false;
}

/**
 * IniFile to store a configuration.
 */
class ConfigIniFile : public IniFile {
private:
        inline static const IniGroupNameList list_group_names = {
                "bans",
                "newgrf",
                "servers",
                "server_bind_addresses",
                "server_authorized_keys",
                "rcon_authorized_keys",
                "admin_authorized_keys"
        };

public:
        ConfigIniFile(const std::string &filename) : IniFile(list_group_names)
        {
                this->LoadFromDisk(filename, NO_DIRECTORY);
        }
};

/**
 * Ini-file versions.
 *
 * Sometimes we move settings between different ini-files, as we need to know
 * when we have to load/remove it from the old versus reading it from the new
 * location. These versions assist with situations like that.
 */
enum IniFileVersion : uint32_t {
        IFV_0,                                                 ///< 0  All versions prior to introduction.
        IFV_PRIVATE_SECRETS,                                   ///< 1  PR#9298  Moving of settings from openttd.cfg to private.cfg / secrets.cfg.
        IFV_GAME_TYPE,                                         ///< 2  PR#9515  Convert server_advertise to server_game_type.
        IFV_LINKGRAPH_SECONDS,                                 ///< 3  PR#10610 Store linkgraph update intervals in seconds instead of days.
        IFV_NETWORK_PRIVATE_SETTINGS,                          ///< 4  PR#10762 Move use_relay_service to private settings.

        IFV_AUTOSAVE_RENAME,                                   ///< 5  PR#11143 Renamed values of autosave to be in minutes.
        IFV_RIGHT_CLICK_CLOSE,                                 ///< 6  PR#10204 Add alternative right click to close windows setting.
        IFV_REMOVE_GENERATION_SEED,                            ///< 7  PR#11927 Remove "generation_seed" from configuration.

        IFV_MAX_VERSION,       ///< Highest possible ini-file version.
};

const uint16_t INIFILE_VERSION = (IniFileVersion)(IFV_MAX_VERSION - 1); ///< Current ini-file version of OpenTTD.

/**
 * Find the index value of a ONEofMANY type in a string separated by |
 * @param str the current value of the setting for which a value needs found
 * @param len length of the string
 * @param many full domain of values the ONEofMANY setting can have
 * @return the integer index of the full-list, or SIZE_MAX if not found
 */
size_t OneOfManySettingDesc::ParseSingleValue(const char *str, size_t len, const std::vector<std::string> &many)
{
        /* check if it's an integer */
        if (isdigit(*str)) return std::strtoul(str, nullptr, 0);

        size_t idx = 0;
        for (auto one : many) {
                if (one.size() == len && strncmp(one.c_str(), str, len) == 0) return idx;
                idx++;
        }

        return SIZE_MAX;
}

/**
 * Find whether a string was a boolean true or a boolean false.
 *
 * @param str the current value of the setting for which a value needs found.
 * @return Either true/false, or nullopt if no boolean value found.
 */
std::optional<bool> BoolSettingDesc::ParseSingleValue(const char *str)
{
        if (strcmp(str, "true") == 0 || strcmp(str, "on") == 0 || strcmp(str, "1") == 0) return true;
        if (strcmp(str, "false") == 0 || strcmp(str, "off") == 0 || strcmp(str, "0") == 0) return false;

        return std::nullopt;
}

/**
 * Find the set-integer value MANYofMANY type in a string
 * @param many full domain of values the MANYofMANY setting can have
 * @param str the current string value of the setting, each individual
 * of separated by a whitespace,tab or | character
 * @return the 'fully' set integer, or SIZE_MAX if a set is not found
 */
static size_t LookupManyOfMany(const std::vector<std::string> &many, const char *str)
{
        const char *s;
        size_t r;
        size_t res = 0;

        for (;;) {
                /* skip "whitespace" */
                while (*str == ' ' || *str == '\t' || *str == '|') str++;
                if (*str == 0) break;

                s = str;
                while (*s != 0 && *s != ' ' && *s != '\t' && *s != '|') s++;

                r = OneOfManySettingDesc::ParseSingleValue(str, s - str, many);
                if (r == SIZE_MAX) return r;

                SetBit(res, (uint8_t)r); // value found, set it
                if (*s == 0) break;
                str = s + 1;
        }
        return res;
}

/**
 * Parse a string into a vector of uint32s.
 * @param p the string to be parsed. Each element in the list is separated by a comma or a space character
 * @return std::optional with a vector of parsed integers. The optional is empty upon an error.
 */
static std::optional<std::vector<uint32_t>> ParseIntList(const char *p)
{
        bool comma = false; // do we accept comma?
        std::vector<uint32_t> result;

        while (*p != '\0') {
                switch (*p) {
                        case ',':
                                /* Do not accept multiple commas between numbers */
                                if (!comma) return std::nullopt;
                                comma = false;
                                [[fallthrough]];

                        case ' ':
                                p++;
                                break;

                        default: {
                                char *end;
                                unsigned long v = std::strtoul(p, &end, 0);
                                if (p == end) return std::nullopt; // invalid character (not a number)

                                result.push_back(ClampTo<uint32_t>(v));
                                p = end; // first non-number
                                comma = true; // we accept comma now
                                break;
                        }
                }
        }

        /* If we have read comma but no number after it, fail.
         * We have read comma when (n != 0) and comma is not allowed */
        if (!result.empty() && !comma) return std::nullopt;

        return result;
}

/**
 * Load parsed string-values into an integer-array (intlist)
 * @param str the string that contains the values (and will be parsed)
 * @param array pointer to the integer-arrays that will be filled
 * @param nelems the number of elements the array holds.
 * @param type the type of elements the array holds (eg INT8, UINT16, etc.)
 * @return return true on success and false on error
 */
static bool LoadIntList(const char *str, void *array, int nelems, VarType type)
{
        size_t elem_size = SlVarSize(type);
        if (str == nullptr) {
                memset(array, 0, nelems * elem_size);
                return true;
        }

        auto opt_items = ParseIntList(str);
        if (!opt_items.has_value() || opt_items->size() != (size_t)nelems) return false;

        char *p = static_cast<char *>(array);
        for (auto item : *opt_items) {
                WriteValue(p, type, item);
                p += elem_size;
        }
        return true;
}

/**
 * Convert an integer-array (intlist) to a string representation. Each value
 * is separated by a comma or a space character
 * @param buf output buffer where the string-representation will be stored
 * @param last last item to write to in the output buffer
 * @param array pointer to the integer-arrays that is read from
 * @param nelems the number of elements the array holds.
 * @param type the type of elements the array holds (eg INT8, UINT16, etc.)
 */
std::string ListSettingDesc::FormatValue(const void *object) const
{
        const uint8_t *p = static_cast<const uint8_t *>(GetVariableAddress(object, this->save));

        std::string result;
        for (size_t i = 0; i != this->save.length; i++) {
                int64_t v;
                switch (GetVarMemType(this->save.conv)) {
                        case SLE_VAR_BL:
                        case SLE_VAR_I8:  v = *(const   int8_t *)p; p += 1; break;
                        case SLE_VAR_U8:  v = *(const  uint8_t *)p; p += 1; break;
                        case SLE_VAR_I16: v = *(const  int16_t *)p; p += 2; break;
                        case SLE_VAR_U16: v = *(const uint16_t *)p; p += 2; break;
                        case SLE_VAR_I32: v = *(const  int32_t *)p; p += 4; break;
                        case SLE_VAR_U32: v = *(const uint32_t *)p; p += 4; break;
                        default: NOT_REACHED();
                }
                if (i != 0) result += ',';
                result += std::to_string(v);
        }
        return result;
}

std::string OneOfManySettingDesc::FormatSingleValue(uint id) const
{
        if (id >= this->many.size()) {
                return std::to_string(id);
        }
        return this->many[id];
}

std::string OneOfManySettingDesc::FormatValue(const void *object) const
{
        uint id = (uint)this->Read(object);
        return this->FormatSingleValue(id);
}

std::string ManyOfManySettingDesc::FormatValue(const void *object) const
{
        uint bitmask = (uint)this->Read(object);
        if (bitmask == 0) {
                return {};
        }

        std::string result;
        for (uint id : SetBitIterator(bitmask)) {
                if (!result.empty()) result += '|';
                result += this->FormatSingleValue(id);
        }
        return result;
}

/**
 * Convert a string representation (external) of an integer-like setting to an integer.
 * @param str Input string that will be parsed based on the type of desc.
 * @return The value from the parse string, or the default value of the setting.
 */
size_t IntSettingDesc::ParseValue(const char *str) const
{
        char *end;
        size_t val = std::strtoul(str, &end, 0);
        if (end == str) {
                ErrorMessageData msg(STR_CONFIG_ERROR, STR_CONFIG_ERROR_INVALID_VALUE);
                msg.SetDParamStr(0, str);
                msg.SetDParamStr(1, this->GetName());
                _settings_error_list.push_back(msg);
                return this->def;
        }
        if (*end != '\0') {
                ErrorMessageData msg(STR_CONFIG_ERROR, STR_CONFIG_ERROR_TRAILING_CHARACTERS);
                msg.SetDParamStr(0, this->GetName());
                _settings_error_list.push_back(msg);
        }
        return val;
}

size_t OneOfManySettingDesc::ParseValue(const char *str) const
{
        size_t r = OneOfManySettingDesc::ParseSingleValue(str, strlen(str), this->many);
        /* if the first attempt of conversion from string to the appropriate value fails,
         * look if we have defined a converter from old value to new value. */
        if (r == SIZE_MAX && this->many_cnvt != nullptr) r = this->many_cnvt(str);
        if (r != SIZE_MAX) return r; // and here goes converted value

        ErrorMessageData msg(STR_CONFIG_ERROR, STR_CONFIG_ERROR_INVALID_VALUE);
        msg.SetDParamStr(0, str);
        msg.SetDParamStr(1, this->GetName());
        _settings_error_list.push_back(msg);
        return this->def;
}

size_t ManyOfManySettingDesc::ParseValue(const char *str) const
{
        size_t r = LookupManyOfMany(this->many, str);
        if (r != SIZE_MAX) return r;
        ErrorMessageData msg(STR_CONFIG_ERROR, STR_CONFIG_ERROR_INVALID_VALUE);
        msg.SetDParamStr(0, str);
        msg.SetDParamStr(1, this->GetName());
        _settings_error_list.push_back(msg);
        return this->def;
}

size_t BoolSettingDesc::ParseValue(const char *str) const
{
        auto r = BoolSettingDesc::ParseSingleValue(str);
        if (r.has_value()) return *r;

        ErrorMessageData msg(STR_CONFIG_ERROR, STR_CONFIG_ERROR_INVALID_VALUE);
        msg.SetDParamStr(0, str);
        msg.SetDParamStr(1, this->GetName());
        _settings_error_list.push_back(msg);
        return this->def;
}

/**
 * Get the title of the setting.
 * The string should include a {STRING2} to show the current value.
 * @return The title string.
 */
StringID IntSettingDesc::GetTitle() const
{
        return this->get_title_cb != nullptr ? this->get_title_cb(*this) : this->str;
}

/**
 * Get the help text of the setting.
 * @return The requested help text.
 */
StringID IntSettingDesc::GetHelp() const
{
        return this->get_help_cb != nullptr ? this->get_help_cb(*this) : this->str_help;
}

/**
 * Set the DParams for drawing the value of the setting.
 * @param first_param First DParam to use
 * @param value Setting value to set params for.
 */
void IntSettingDesc::SetValueDParams(uint first_param, int32_t value) const
{
        if (this->set_value_dparams_cb != nullptr) {
                this->set_value_dparams_cb(*this, first_param, value);
        } else if (this->IsBoolSetting()) {
                SetDParam(first_param++, value != 0 ? STR_CONFIG_SETTING_ON : STR_CONFIG_SETTING_OFF);
        } else {
                if ((this->flags & SF_GUI_DROPDOWN) != 0) {
                        SetDParam(first_param++, this->str_val - this->min + value);
                } else {
                        SetDParam(first_param++, this->str_val + ((value == 0 && (this->flags & SF_GUI_0_IS_SPECIAL) != 0) ? 1 : 0));
                }
                SetDParam(first_param++, value);
        }
}

/**
 * Make the value valid and then write it to the setting.
 * See #MakeValidValid and #Write for more details.
 * @param object The object the setting is to be saved in.
 * @param val Signed version of the new value.
 */
void IntSettingDesc::MakeValueValidAndWrite(const void *object, int32_t val) const
{
        this->MakeValueValid(val);
        this->Write(object, val);
}

/**
 * Make the value valid given the limitations of this setting.
 *
 * In the case of int settings this is ensuring the value is between the minimum and
 * maximum value, with a special case for 0 if SF_GUI_0_IS_SPECIAL is set.
 * This is generally done by clamping the value so it is within the allowed value range.
 * However, for SF_GUI_DROPDOWN the default is used when the value is not valid.
 * @param val The value to make valid.
 */
void IntSettingDesc::MakeValueValid(int32_t &val) const
{
        /* We need to take special care of the uint32_t type as we receive from the function
         * a signed integer. While here also bail out on 64-bit settings as those are not
         * supported. Unsigned 8 and 16-bit variables are safe since they fit into a signed
         * 32-bit variable
         * TODO: Support 64-bit settings/variables; requires 64 bit over command protocol! */
        switch (GetVarMemType(this->save.conv)) {
                case SLE_VAR_NULL: return;
                case SLE_VAR_BL:
                case SLE_VAR_I8:
                case SLE_VAR_U8:
                case SLE_VAR_I16:
                case SLE_VAR_U16:
                case SLE_VAR_I32: {
                        /* Override the minimum value. No value below this->min, except special value 0 */
                        if (!(this->flags & SF_GUI_0_IS_SPECIAL) || val != 0) {
                                if (!(this->flags & SF_GUI_DROPDOWN)) {
                                        /* Clamp value-type setting to its valid range */
                                        val = Clamp(val, this->min, this->max);
                                } else if (val < this->min || val > (int32_t)this->max) {
                                        /* Reset invalid discrete setting (where different values change gameplay) to its default value */
                                        val = this->def;
                                }
                        }
                        break;
                }
                case SLE_VAR_U32: {
                        /* Override the minimum value. No value below this->min, except special value 0 */
                        uint32_t uval = (uint32_t)val;
                        if (!(this->flags & SF_GUI_0_IS_SPECIAL) || uval != 0) {
                                if (!(this->flags & SF_GUI_DROPDOWN)) {
                                        /* Clamp value-type setting to its valid range */
                                        uval = ClampU(uval, this->min, this->max);
                                } else if (uval < (uint)this->min || uval > this->max) {
                                        /* Reset invalid discrete setting to its default value */
                                        uval = (uint32_t)this->def;
                                }
                        }
                        val = (int32_t)uval;
                        return;
                }
                case SLE_VAR_I64:
                case SLE_VAR_U64:
                default: NOT_REACHED();
        }
}

/**
 * Set the value of a setting.
 * @param object The object the setting is to be saved in.
 * @param val Signed version of the new value.
 */
void IntSettingDesc::Write(const void *object, int32_t val) const
{
        void *ptr = GetVariableAddress(object, this->save);
        WriteValue(ptr, this->save.conv, (int64_t)val);
}

/**
 * Read the integer from the the actual setting.
 * @param object The object the setting is to be saved in.
 * @return The value of the saved integer.
 */
int32_t IntSettingDesc::Read(const void *object) const
{
        void *ptr = GetVariableAddress(object, this->save);
        return (int32_t)ReadValue(ptr, this->save.conv);
}

/**
 * Make the value valid given the limitations of this setting.
 *
 * In the case of string settings this is ensuring the string contains only accepted
 * Utf8 characters and is at most the maximum length defined in this setting.
 * @param str The string to make valid.
 */
void StringSettingDesc::MakeValueValid(std::string &str) const
{
        if (this->max_length == 0 || str.size() < this->max_length) return;

        /* In case a maximum length is imposed by the setting, the length
         * includes the '\0' termination for network transfer purposes.
         * Also ensure the string is valid after chopping of some bytes. */
        std::string stdstr(str, 0, this->max_length - 1);
        str.assign(StrMakeValid(stdstr, SVS_NONE));
}

/**
 * Write a string to the actual setting.
 * @param object The object the setting is to be saved in.
 * @param str The string to save.
 */
void StringSettingDesc::Write(const void *object, const std::string &str) const
{
        reinterpret_cast<std::string *>(GetVariableAddress(object, this->save))->assign(str);
}

/**
 * Read the string from the the actual setting.
 * @param object The object the setting is to be saved in.
 * @return The value of the saved string.
 */
const std::string &StringSettingDesc::Read(const void *object) const
{
        return *reinterpret_cast<std::string *>(GetVariableAddress(object, this->save));
}

/**
 * Load values from a group of an IniFile structure into the internal representation
 * @param ini pointer to IniFile structure that holds administrative information
 * @param settings_table table with SettingDesc structures whose internally pointed variables will
 *        be given values
 * @param grpname the group of the IniFile to search in for the new values
 * @param object pointer to the object been loaded
 * @param only_startup load only the startup settings set
 */
static void IniLoadSettings(IniFile &ini, const SettingTable &settings_table, const char *grpname, void *object, bool only_startup)
{
        const IniGroup *group;
        const IniGroup *group_def = ini.GetGroup(grpname);

        for (auto &desc : settings_table) {
                const SettingDesc *sd = GetSettingDesc(desc);
                if (!SlIsObjectCurrentlyValid(sd->save.version_from, sd->save.version_to)) continue;
                if (sd->startup != only_startup) continue;

                /* For settings.xx.yy load the settings from [xx] yy = ? */
                std::string s{ sd->GetName() };
                auto sc = s.find('.');
                if (sc != std::string::npos) {
                        group = ini.GetGroup(s.substr(0, sc));
                        if (group == nullptr) group = group_def;
                        s = s.substr(sc + 1);
                } else {
                        group = group_def;
                }

                const IniItem *item = nullptr;
                if (group != nullptr) item = group->GetItem(s);
                if (item == nullptr && group != group_def && group_def != nullptr) {
                        /* For settings.xx.yy load the settings from [settings] yy = ? in case the previous
                         * did not exist (e.g. loading old config files with a [settings] section */
                        item = group_def->GetItem(s);
                }
                if (item == nullptr) {
                        /* For settings.xx.zz.yy load the settings from [zz] yy = ? in case the previous
                         * did not exist (e.g. loading old config files with a [yapf] section */
                        sc = s.find('.');
                        if (sc != std::string::npos) {
                                if (group = ini.GetGroup(s.substr(0, sc)); group != nullptr) item = group->GetItem(s.substr(sc + 1));
                        }
                }

                sd->ParseValue(item, object);
        }
}

void IntSettingDesc::ParseValue(const IniItem *item, void *object) const
{
        size_t val = (item == nullptr) ? this->def : this->ParseValue(item->value.has_value() ? item->value->c_str() : "");
        this->MakeValueValidAndWrite(object, (int32_t)val);
}

void StringSettingDesc::ParseValue(const IniItem *item, void *object) const
{
        std::string str = (item == nullptr) ? this->def : item->value.value_or("");
        this->MakeValueValid(str);
        this->Write(object, str);
}

void ListSettingDesc::ParseValue(const IniItem *item, void *object) const
{
        const char *str = (item == nullptr) ? this->def : item->value.has_value() ? item->value->c_str() : nullptr;
        void *ptr = GetVariableAddress(object, this->save);
        if (!LoadIntList(str, ptr, this->save.length, GetVarMemType(this->save.conv))) {
                ErrorMessageData msg(STR_CONFIG_ERROR, STR_CONFIG_ERROR_ARRAY);
                msg.SetDParamStr(0, this->GetName());
                _settings_error_list.push_back(msg);

                /* Use default */
                LoadIntList(this->def, ptr, this->save.length, GetVarMemType(this->save.conv));
        }
}

/**
 * Save the values of settings to the inifile.
 * @param ini pointer to IniFile structure
 * @param sd read-only SettingDesc structure which contains the unmodified,
 *        loaded values of the configuration file and various information about it
 * @param grpname holds the name of the group (eg. [network]) where these will be saved
 * @param object pointer to the object been saved
 * The function works as follows: for each item in the SettingDesc structure we
 * have a look if the value has changed since we started the game (the original
 * values are reloaded when saving). If settings indeed have changed, we get
 * these and save them.
 */
static void IniSaveSettings(IniFile &ini, const SettingTable &settings_table, const char *grpname, void *object, bool)
{
        IniGroup *group_def = nullptr, *group;

        for (auto &desc : settings_table) {
                const SettingDesc *sd = GetSettingDesc(desc);
                /* If the setting is not saved to the configuration
                 * file, just continue with the next setting */
                if (!SlIsObjectCurrentlyValid(sd->save.version_from, sd->save.version_to)) continue;
                if (sd->flags & SF_NOT_IN_CONFIG) continue;

                /* XXX - wtf is this?? (group override?) */
                std::string s{ sd->GetName() };
                auto sc = s.find('.');
                if (sc != std::string::npos) {
                        group = &ini.GetOrCreateGroup(s.substr(0, sc));
                        s = s.substr(sc + 1);
                } else {
                        if (group_def == nullptr) group_def = &ini.GetOrCreateGroup(grpname);
                        group = group_def;
                }

                IniItem &item = group->GetOrCreateItem(s);

                if (!item.value.has_value() || !sd->IsSameValue(&item, object)) {
                        /* The value is different, that means we have to write it to the ini */
                        item.value.emplace(sd->FormatValue(object));
                }
        }
}

std::string IntSettingDesc::FormatValue(const void *object) const
{
        int64_t i;
        if (IsSignedVarMemType(this->save.conv)) {
                i = this->Read(object);
        } else {
                i = (uint32_t)this->Read(object);
        }
        return std::to_string(i);
}

std::string BoolSettingDesc::FormatValue(const void *object) const
{
        bool val = this->Read(object) != 0;
        return val ? "true" : "false";
}

bool IntSettingDesc::IsSameValue(const IniItem *item, void *object) const
{
        int32_t item_value = (int32_t)this->ParseValue(item->value->c_str());
        int32_t object_value = this->Read(object);
        return item_value == object_value;
}

bool IntSettingDesc::IsDefaultValue(void *object) const
{
        int32_t object_value = this->Read(object);
        return this->def == object_value;
}

void IntSettingDesc::ResetToDefault(void *object) const
{
        this->Write(object, this->def);
}

std::string StringSettingDesc::FormatValue(const void *object) const
{
        const std::string &str = this->Read(object);
        switch (GetVarMemType(this->save.conv)) {
                case SLE_VAR_STR: return str;

                case SLE_VAR_STRQ:
                        if (str.empty()) {
                                return str;
                        }
                        return fmt::format("\"{}\"", str);

                default: NOT_REACHED();
        }
}

bool StringSettingDesc::IsSameValue(const IniItem *item, void *object) const
{
        /* The ini parsing removes the quotes, which are needed to retain the spaces in STRQs,
         * so those values are always different in the parsed ini item than they should be. */
        if (GetVarMemType(this->save.conv) == SLE_VAR_STRQ) return false;

        const std::string &str = this->Read(object);
        return item->value->compare(str) == 0;
}

bool StringSettingDesc::IsDefaultValue(void *object) const
{
        const std::string &str = this->Read(object);
        return this->def == str;
}

void StringSettingDesc::ResetToDefault(void *object) const
{
        this->Write(object, this->def);
}

bool ListSettingDesc::IsSameValue(const IniItem *, void *) const
{
        /* Checking for equality is way more expensive than just writing the value. */
        return false;
}

bool ListSettingDesc::IsDefaultValue(void *) const
{
        /* Defaults of lists are often complicated, and hard to compare. */
        return false;
}

void ListSettingDesc::ResetToDefault(void *) const
{
        /* Resetting a list to default is not supported. */
        NOT_REACHED();
}

/**
 * Loads all items from a 'grpname' section into a list
 * The list parameter can be a nullptr pointer, in this case nothing will be
 * saved and a callback function should be defined that will take over the
 * list-handling and store the data itself somewhere.
 * @param ini IniFile handle to the ini file with the source data
 * @param grpname character string identifying the section-header of the ini file that will be parsed
 * @param list new list with entries of the given section
 */
static void IniLoadSettingList(IniFile &ini, const char *grpname, StringList &list)
{
        const IniGroup *group = ini.GetGroup(grpname);

        if (group == nullptr) return;

        list.clear();

        for (const IniItem &item : group->items) {
                if (!item.name.empty()) list.push_back(item.name);
        }
}

/**
 * Saves all items from a list into the 'grpname' section
 * The list parameter can be a nullptr pointer, in this case a callback function
 * should be defined that will provide the source data to be saved.
 * @param ini IniFile handle to the ini file where the destination data is saved
 * @param grpname character string identifying the section-header of the ini file
 * @param list pointer to an string(pointer) array that will be used as the
 *             source to be saved into the relevant ini section
 */
static void IniSaveSettingList(IniFile &ini, const char *grpname, StringList &list)
{
        IniGroup &group = ini.GetOrCreateGroup(grpname);
        group.Clear();

        for (const auto &iter : list) {
                group.GetOrCreateItem(iter).SetValue("");
        }
}

/**
 * Load a WindowDesc from config.
 * @param ini IniFile handle to the ini file with the source data
 * @param grpname character string identifying the section-header of the ini file that will be parsed
 * @param desc Destination WindowDesc
 */
void IniLoadWindowSettings(IniFile &ini, const char *grpname, void *desc)
{
        IniLoadSettings(ini, _window_settings, grpname, desc, false);
}

/**
 * Save a WindowDesc to config.
 * @param ini IniFile handle to the ini file where the destination data is saved
 * @param grpname character string identifying the section-header of the ini file
 * @param desc Source WindowDesc
 */
void IniSaveWindowSettings(IniFile &ini, const char *grpname, void *desc)
{
        IniSaveSettings(ini, _window_settings, grpname, desc, false);
}

/**
 * Check whether the setting is editable in the current gamemode.
 * @param do_command true if this is about checking a command from the server.
 * @return true if editable.
 */
bool SettingDesc::IsEditable(bool do_command) const
{
        if (!do_command && !(this->flags & SF_NO_NETWORK_SYNC) && _networking && !_network_server && !(this->flags & SF_PER_COMPANY)) return false;
        if (do_command && (this->flags & SF_NO_NETWORK_SYNC)) return false;
        if ((this->flags & SF_NETWORK_ONLY) && !_networking && _game_mode != GM_MENU) return false;
        if ((this->flags & SF_NO_NETWORK) && _networking) return false;
        if ((this->flags & SF_NEWGAME_ONLY) &&
                        (_game_mode == GM_NORMAL ||
                        (_game_mode == GM_EDITOR && !(this->flags & SF_SCENEDIT_TOO)))) return false;
        if ((this->flags & SF_SCENEDIT_ONLY) && _game_mode != GM_EDITOR) return false;
        return true;
}

/**
 * Return the type of the setting.
 * @return type of setting
 */
SettingType SettingDesc::GetType() const
{
        if (this->flags & SF_PER_COMPANY) return ST_COMPANY;
        return (this->flags & SF_NOT_IN_SAVE) ? ST_CLIENT : ST_GAME;
}

/**
 * Get the setting description of this setting as an integer setting.
 * @return The integer setting description.
 */
const IntSettingDesc *SettingDesc::AsIntSetting() const
{
        assert(this->IsIntSetting());
        return static_cast<const IntSettingDesc *>(this);
}

/**
 * Get the setting description of this setting as a string setting.
 * @return The string setting description.
 */
const StringSettingDesc *SettingDesc::AsStringSetting() const
{
        assert(this->IsStringSetting());
        return static_cast<const StringSettingDesc *>(this);
}

void PrepareOldDiffCustom();
void HandleOldDiffCustom(bool savegame);


/** Checks if any settings are set to incorrect values, and sets them to correct values in that case. */
static void ValidateSettings()
{
        /* Do not allow a custom sea level with the original land generator. */
        if (_settings_newgame.game_creation.land_generator == LG_ORIGINAL &&
                        _settings_newgame.difficulty.quantity_sea_lakes == CUSTOM_SEA_LEVEL_NUMBER_DIFFICULTY) {
                _settings_newgame.difficulty.quantity_sea_lakes = CUSTOM_SEA_LEVEL_MIN_PERCENTAGE;
        }
}

static void AILoadConfig(const IniFile &ini, const char *grpname)
{
        const IniGroup *group = ini.GetGroup(grpname);

        /* Clean any configured AI */
        for (CompanyID c = COMPANY_FIRST; c < MAX_COMPANIES; c++) {
                AIConfig::GetConfig(c, AIConfig::SSS_FORCE_NEWGAME)->Change(std::nullopt);
        }

        /* If no group exists, return */
        if (group == nullptr) return;

        CompanyID c = COMPANY_FIRST;
        for (const IniItem &item : group->items) {
                AIConfig *config = AIConfig::GetConfig(c, AIConfig::SSS_FORCE_NEWGAME);

                config->Change(item.name);
                if (!config->HasScript()) {
                        if (item.name != "none") {
                                Debug(script, 0, "The AI by the name '{}' was no longer found, and removed from the list.", item.name);
                                continue;
                        }
                }
                if (item.value.has_value()) config->StringToSettings(*item.value);
                c++;
                if (c >= MAX_COMPANIES) break;
        }
}

static void GameLoadConfig(const IniFile &ini, const char *grpname)
{
        const IniGroup *group = ini.GetGroup(grpname);

        /* Clean any configured GameScript */
        GameConfig::GetConfig(GameConfig::SSS_FORCE_NEWGAME)->Change(std::nullopt);

        /* If no group exists, return */
        if (group == nullptr || group->items.empty()) return;

        const IniItem &item = group->items.front();

        GameConfig *config = GameConfig::GetConfig(AIConfig::SSS_FORCE_NEWGAME);

        config->Change(item.name);
        if (!config->HasScript()) {
                if (item.name != "none") {
                        Debug(script, 0, "The GameScript by the name '{}' was no longer found, and removed from the list.", item.name);
                        return;
                }
        }
        if (item.value.has_value()) config->StringToSettings(*item.value);
}

/**
 * Load BaseGraphics set selection and configuration.
 */
static void GraphicsSetLoadConfig(IniFile &ini)
{
        if (const IniGroup *group = ini.GetGroup("misc"); group != nullptr) {
                /* Load old setting first. */
                if (const IniItem *item = group->GetItem("graphicsset"); item != nullptr && item->value) BaseGraphics::ini_data.name = *item->value;
        }

        if (const IniGroup *group = ini.GetGroup("graphicsset"); group != nullptr) {
                /* Load new settings. */
                if (const IniItem *item = group->GetItem("name"); item != nullptr && item->value) BaseGraphics::ini_data.name = *item->value;

                if (const IniItem *item = group->GetItem("shortname"); item != nullptr && item->value && item->value->size() == 8) {
                        BaseGraphics::ini_data.shortname = BSWAP32(std::strtoul(item->value->c_str(), nullptr, 16));
                }

                if (const IniItem *item = group->GetItem("extra_version"); item != nullptr && item->value) BaseGraphics::ini_data.extra_version = std::strtoul(item->value->c_str(), nullptr, 10);

                if (const IniItem *item = group->GetItem("extra_params"); item != nullptr && item->value) {
                        auto params = ParseIntList(item->value->c_str());
                        if (params.has_value()) {
                                BaseGraphics::ini_data.extra_params = params.value();
                        } else {
                                SetDParamStr(0, BaseGraphics::ini_data.name);
                                ShowErrorMessage(STR_CONFIG_ERROR, STR_CONFIG_ERROR_ARRAY, WL_CRITICAL);
                        }
                }
        }
}

/**
 * Load a GRF configuration
 * @param ini       The configuration to read from.
 * @param grpname   Group name containing the configuration of the GRF.
 * @param is_static GRF is static.
 */
static GRFConfig *GRFLoadConfig(const IniFile &ini, const char *grpname, bool is_static)
{
        const IniGroup *group = ini.GetGroup(grpname);
        GRFConfig *first = nullptr;
        GRFConfig **curr = &first;

        if (group == nullptr) return nullptr;

        uint num_grfs = 0;
        for (const IniItem &item : group->items) {
                GRFConfig *c = nullptr;

                std::array<uint8_t, 4> grfid_buf;
                MD5Hash md5sum;
                std::string_view item_name = item.name;
                bool has_md5sum = false;

                /* Try reading "<grfid>|" and on success, "<md5sum>|". */
                auto grfid_pos = item_name.find("|");
                if (grfid_pos != std::string_view::npos) {
                        std::string_view grfid_str = item_name.substr(0, grfid_pos);

                        if (ConvertHexToBytes(grfid_str, grfid_buf)) {
                                item_name = item_name.substr(grfid_pos + 1);

                                auto md5sum_pos = item_name.find("|");
                                if (md5sum_pos != std::string_view::npos) {
                                        std::string_view md5sum_str = item_name.substr(0, md5sum_pos);

                                        has_md5sum = ConvertHexToBytes(md5sum_str, md5sum);
                                        if (has_md5sum) item_name = item_name.substr(md5sum_pos + 1);
                                }

                                uint32_t grfid = grfid_buf[0] | (grfid_buf[1] << 8) | (grfid_buf[2] << 16) | (grfid_buf[3] << 24);
                                if (has_md5sum) {
                                        const GRFConfig *s = FindGRFConfig(grfid, FGCM_EXACT, &md5sum);
                                        if (s != nullptr) c = new GRFConfig(*s);
                                }
                                if (c == nullptr && !FioCheckFileExists(std::string(item_name), NEWGRF_DIR)) {
                                        const GRFConfig *s = FindGRFConfig(grfid, FGCM_NEWEST_VALID);
                                        if (s != nullptr) c = new GRFConfig(*s);
                                }
                        }
                }
                std::string filename = std::string(item_name);

                if (c == nullptr) c = new GRFConfig(filename);

                /* Parse parameters */
                if (item.value.has_value() && !item.value->empty()) {
                        auto params = ParseIntList(item.value->c_str());
                        if (params.has_value()) {
                                c->SetParams(params.value());
                        } else {
                                SetDParamStr(0, filename);
                                ShowErrorMessage(STR_CONFIG_ERROR, STR_CONFIG_ERROR_ARRAY, WL_CRITICAL);
                        }
                }

                /* Check if item is valid */
                if (!FillGRFDetails(c, is_static) || HasBit(c->flags, GCF_INVALID)) {
                        if (c->status == GCS_NOT_FOUND) {
                                SetDParam(1, STR_CONFIG_ERROR_INVALID_GRF_NOT_FOUND);
                        } else if (HasBit(c->flags, GCF_UNSAFE)) {
                                SetDParam(1, STR_CONFIG_ERROR_INVALID_GRF_UNSAFE);
                        } else if (HasBit(c->flags, GCF_SYSTEM)) {
                                SetDParam(1, STR_CONFIG_ERROR_INVALID_GRF_SYSTEM);
                        } else if (HasBit(c->flags, GCF_INVALID)) {
                                SetDParam(1, STR_CONFIG_ERROR_INVALID_GRF_INCOMPATIBLE);
                        } else {
                                SetDParam(1, STR_CONFIG_ERROR_INVALID_GRF_UNKNOWN);
                        }

                        SetDParamStr(0, filename.empty() ? item.name.c_str() : filename);
                        ShowErrorMessage(STR_CONFIG_ERROR, STR_CONFIG_ERROR_INVALID_GRF, WL_CRITICAL);
                        delete c;
                        continue;
                }

                /* Check for duplicate GRFID (will also check for duplicate filenames) */
                bool duplicate = false;
                for (const GRFConfig *gc = first; gc != nullptr; gc = gc->next) {
                        if (gc->ident.grfid == c->ident.grfid) {
                                SetDParamStr(0, c->filename);
                                SetDParamStr(1, gc->filename);
                                ShowErrorMessage(STR_CONFIG_ERROR, STR_CONFIG_ERROR_DUPLICATE_GRFID, WL_CRITICAL);
                                duplicate = true;
                                break;
                        }
                }
                if (duplicate) {
                        delete c;
                        continue;
                }

                if (is_static) {
                        /* Mark file as static to avoid saving in savegame. */
                        SetBit(c->flags, GCF_STATIC);
                } else if (++num_grfs > NETWORK_MAX_GRF_COUNT) {
                        /* Check we will not load more non-static NewGRFs than allowed. This could trigger issues for game servers. */
                        ShowErrorMessage(STR_CONFIG_ERROR, STR_NEWGRF_ERROR_TOO_MANY_NEWGRFS_LOADED, WL_CRITICAL);
                        break;
                }

                /* Add item to list */
                *curr = c;
                curr = &c->next;
        }

        return first;
}

static IniFileVersion LoadVersionFromConfig(const IniFile &ini)
{
        const IniGroup *group = ini.GetGroup("version");
        if (group == nullptr) return IFV_0;

        auto version_number = group->GetItem("ini_version");
        /* Older ini-file versions don't have this key yet. */
        if (version_number == nullptr || !version_number->value.has_value()) return IFV_0;

        uint32_t version = 0;
        std::from_chars(version_number->value->data(), version_number->value->data() + version_number->value->size(), version);

        return static_cast<IniFileVersion>(version);
}

static void AISaveConfig(IniFile &ini, const char *grpname)
{
        IniGroup &group = ini.GetOrCreateGroup(grpname);
        group.Clear();

        for (CompanyID c = COMPANY_FIRST; c < MAX_COMPANIES; c++) {
                AIConfig *config = AIConfig::GetConfig(c, AIConfig::SSS_FORCE_NEWGAME);
                std::string name;
                std::string value = config->SettingsToString();

                if (config->HasScript()) {
                        name = config->GetName();
                } else {
                        name = "none";
                }

                group.CreateItem(name).SetValue(value);
        }
}

static void GameSaveConfig(IniFile &ini, const char *grpname)
{
        IniGroup &group = ini.GetOrCreateGroup(grpname);
        group.Clear();

        GameConfig *config = GameConfig::GetConfig(AIConfig::SSS_FORCE_NEWGAME);
        std::string name;
        std::string value = config->SettingsToString();

        if (config->HasScript()) {
                name = config->GetName();
        } else {
                name = "none";
        }

        group.CreateItem(name).SetValue(value);
}

/**
 * Save the version of OpenTTD to the ini file.
 * @param ini the ini to write to
 */
static void SaveVersionInConfig(IniFile &ini)
{
        IniGroup &group = ini.GetOrCreateGroup("version");
        group.GetOrCreateItem("version_string").SetValue(_openttd_revision);
        group.GetOrCreateItem("version_number").SetValue(fmt::format("{:08X}", _openttd_newgrf_version));
        group.GetOrCreateItem("ini_version").SetValue(std::to_string(INIFILE_VERSION));
}

/**
 * Save BaseGraphics set selection and configuration.
 */
static void GraphicsSetSaveConfig(IniFile &ini)
{
        const GraphicsSet *used_set = BaseGraphics::GetUsedSet();
        if (used_set == nullptr) return;

        IniGroup &group = ini.GetOrCreateGroup("graphicsset");
        group.Clear();

        group.GetOrCreateItem("name").SetValue(used_set->name);
        group.GetOrCreateItem("shortname").SetValue(fmt::format("{:08X}", BSWAP32(used_set->shortname)));

        const GRFConfig *extra_cfg = used_set->GetExtraConfig();
        if (extra_cfg != nullptr && extra_cfg->num_params > 0) {
                group.GetOrCreateItem("extra_version").SetValue(fmt::format("{}", extra_cfg->version));
                group.GetOrCreateItem("extra_params").SetValue(GRFBuildParamList(extra_cfg));
        }
}

/* Save a GRF configuration to the given group name */
static void GRFSaveConfig(IniFile &ini, const char *grpname, const GRFConfig *list)
{
        IniGroup &group = ini.GetOrCreateGroup(grpname);
        group.Clear();
        const GRFConfig *c;

        for (c = list; c != nullptr; c = c->next) {
                std::string key = fmt::format("{:08X}|{}|{}", BSWAP32(c->ident.grfid),
                                FormatArrayAsHex(c->ident.md5sum), c->filename);
                group.GetOrCreateItem(key).SetValue(GRFBuildParamList(c));
        }
}

/* Common handler for saving/loading variables to the configuration file */
static void HandleSettingDescs(IniFile &generic_ini, IniFile &private_ini, IniFile &secrets_ini, SettingDescProc *proc, SettingDescProcList *proc_list, bool only_startup = false)
{
        proc(generic_ini, _misc_settings, "misc", nullptr, only_startup);
#if defined(_WIN32) && !defined(DEDICATED)
        proc(generic_ini, _win32_settings, "win32", nullptr, only_startup);
#endif /* _WIN32 */

        /* The name "patches" is a fallback, as every setting should sets its own group. */

        for (auto &table : GenericSettingTables()) {
                proc(generic_ini, table, "patches", &_settings_newgame, only_startup);
        }
        for (auto &table : PrivateSettingTables()) {
                proc(private_ini, table, "patches", &_settings_newgame, only_startup);
        }
        for (auto &table : SecretSettingTables()) {
                proc(secrets_ini, table, "patches", &_settings_newgame, only_startup);
        }

        proc(generic_ini, _currency_settings, "currency", &GetCustomCurrency(), only_startup);
        proc(generic_ini, _company_settings, "company", &_settings_client.company, only_startup);

        if (!only_startup) {
                proc_list(private_ini, "server_bind_addresses", _network_bind_list);
                proc_list(private_ini, "servers", _network_host_list);
                proc_list(private_ini, "bans", _network_ban_list);
                proc_list(private_ini, "server_authorized_keys", _settings_client.network.server_authorized_keys);
                proc_list(private_ini, "rcon_authorized_keys", _settings_client.network.rcon_authorized_keys);
                proc_list(private_ini, "admin_authorized_keys", _settings_client.network.admin_authorized_keys);
        }
}

/**
 * Remove all entries from a settings table from an ini-file.
 *
 * This is only useful if those entries are moved to another file, and you
 * want to clean up what is left behind.
 *
 * @param ini The ini file to remove the entries from.
 * @param table The table to look for entries to remove.
 */
static void RemoveEntriesFromIni(IniFile &ini, const SettingTable &table)
{
        for (auto &desc : table) {
                const SettingDesc *sd = GetSettingDesc(desc);

                /* For settings.xx.yy load the settings from [xx] yy = ? */
                std::string s{ sd->GetName() };
                auto sc = s.find('.');
                if (sc == std::string::npos) continue;

                IniGroup *group = ini.GetGroup(s.substr(0, sc));
                if (group == nullptr) continue;
                s = s.substr(sc + 1);

                group->RemoveItem(s);
        }
}

/**
 * Check whether a conversion should be done, and based on what old setting information.
 *
 * To prevent errors when switching back and forth between older and newer
 * version of OpenTTD, the type of a setting is never changed. Instead, the
 * setting is renamed, and this function is used to check whether a conversion
 * between the old and new setting is required.
 *
 * This checks if the new setting doesn't exist, and if the old does.
 *
 * Doing it this way means that if you switch to an older client, the old
 * setting is used, and only on the first time starting a new client, the
 * old setting is converted to the new. After that, they are independent
 * of each other. And you can safely, without errors on either, switch
 * between old and new client.
 *
 * @param ini The ini-file to use.
 * @param group The group the setting is in.
 * @param old_var The old name of the setting.
 * @param new_var The new name of the setting.
 * @param[out] old_item The old item to base upgrading on.
 * @return Whether upgrading should happen; if false, old_item is a nullptr.
 */
bool IsConversionNeeded(const ConfigIniFile &ini, const std::string &group, const std::string &old_var, const std::string &new_var, const IniItem **old_item)
{
        *old_item = nullptr;

        const IniGroup *igroup = ini.GetGroup(group);
        /* If the group doesn't exist, there is nothing to convert. */
        if (igroup == nullptr) return false;

        const IniItem *tmp_old_item = igroup->GetItem(old_var);
        const IniItem *new_item = igroup->GetItem(new_var);

        /* If the old item doesn't exist, there is nothing to convert. */
        if (tmp_old_item == nullptr) return false;

        /* If the new item exists, it means conversion was already done. We only
         * do the conversion the first time, and after that these settings are
         * independent. This allows users to freely change between older and
         * newer clients without breaking anything. */
        if (new_item != nullptr) return false;

        *old_item = tmp_old_item;
        return true;
}

/**
 * Load the values from the configuration files
 * @param startup Load the minimal amount of the configuration to "bootstrap" the blitter and such.
 */
void LoadFromConfig(bool startup)
{
        ConfigIniFile generic_ini(_config_file);
        ConfigIniFile private_ini(_private_file);
        ConfigIniFile secrets_ini(_secrets_file);
        ConfigIniFile favs_ini(_favs_file);

        if (!startup) ResetCurrencies(false); // Initialize the array of currencies, without preserving the custom one

        IniFileVersion generic_version = LoadVersionFromConfig(generic_ini);

        if (startup) {
                GraphicsSetLoadConfig(generic_ini);
        }

        /* Before the split of private/secrets, we have to look in the generic for these settings. */
        if (generic_version < IFV_PRIVATE_SECRETS) {
                HandleSettingDescs(generic_ini, generic_ini, generic_ini, IniLoadSettings, IniLoadSettingList, startup);
        } else {
                HandleSettingDescs(generic_ini, private_ini, secrets_ini, IniLoadSettings, IniLoadSettingList, startup);
        }

        /* Load basic settings only during bootstrap, load other settings not during bootstrap */
        if (!startup) {
                if (generic_version < IFV_LINKGRAPH_SECONDS) {
                        _settings_newgame.linkgraph.recalc_interval *= CalendarTime::SECONDS_PER_DAY;
                        _settings_newgame.linkgraph.recalc_time     *= CalendarTime::SECONDS_PER_DAY;
                }

                /* Move use_relay_service from generic_ini to private_ini. */
                if (generic_version < IFV_NETWORK_PRIVATE_SETTINGS) {
                        const IniGroup *network = generic_ini.GetGroup("network");
                        if (network != nullptr) {
                                const IniItem *use_relay_service = network->GetItem("use_relay_service");
                                if (use_relay_service != nullptr) {
                                        if (use_relay_service->value == "never") {
                                                _settings_client.network.use_relay_service = UseRelayService::URS_NEVER;
                                        } else if (use_relay_service->value == "ask") {
                                                _settings_client.network.use_relay_service = UseRelayService::URS_ASK;
                                        } else if (use_relay_service->value == "allow") {
                                                _settings_client.network.use_relay_service = UseRelayService::URS_ALLOW;
                                        }
                                }
                        }
                }

                const IniItem *old_item;

                if (generic_version < IFV_GAME_TYPE && IsConversionNeeded(generic_ini, "network", "server_advertise", "server_game_type", &old_item)) {
                        auto old_value = BoolSettingDesc::ParseSingleValue(old_item->value->c_str());
                        _settings_client.network.server_game_type = old_value.value_or(false) ? SERVER_GAME_TYPE_PUBLIC : SERVER_GAME_TYPE_LOCAL;
                }

                if (generic_version < IFV_AUTOSAVE_RENAME && IsConversionNeeded(generic_ini, "gui", "autosave", "autosave_interval", &old_item)) {
                        static std::vector<std::string> _old_autosave_interval{"off", "monthly", "quarterly", "half year", "yearly"};
                        auto old_value = OneOfManySettingDesc::ParseSingleValue(old_item->value->c_str(), old_item->value->size(), _old_autosave_interval);

                        switch (old_value) {
                                case 0: _settings_client.gui.autosave_interval = 0; break;
                                case 1: _settings_client.gui.autosave_interval = 10; break;
                                case 2: _settings_client.gui.autosave_interval = 30; break;
                                case 3: _settings_client.gui.autosave_interval = 60; break;
                                case 4: _settings_client.gui.autosave_interval = 120; break;
                                default: break;
                        }
                }

                /* Persist the right click close option from older versions. */
                if (generic_version < IFV_RIGHT_CLICK_CLOSE && IsConversionNeeded(generic_ini, "gui", "right_mouse_wnd_close", "right_click_wnd_close", &old_item)) {
                        auto old_value = BoolSettingDesc::ParseSingleValue(old_item->value->c_str());
                        _settings_client.gui.right_click_wnd_close = old_value.value_or(false) ? RCC_YES : RCC_NO;
                }

                _grfconfig_newgame = GRFLoadConfig(generic_ini, "newgrf", false);
                _grfconfig_static  = GRFLoadConfig(generic_ini, "newgrf-static", true);
                AILoadConfig(generic_ini, "ai_players");
                GameLoadConfig(generic_ini, "game_scripts");
                PickerLoadConfig(favs_ini);

                PrepareOldDiffCustom();
                IniLoadSettings(generic_ini, _old_gameopt_settings, "gameopt", &_settings_newgame, false);
                HandleOldDiffCustom(false);

                ValidateSettings();
                DebugReconsiderSendRemoteMessages();

                /* Display scheduled errors */
                ScheduleErrorMessage(_settings_error_list);
                if (FindWindowById(WC_ERRMSG, 0) == nullptr) ShowFirstError();
        }
}

/** Save the values to the configuration file */
void SaveToConfig()
{
        ConfigIniFile generic_ini(_config_file);
        ConfigIniFile private_ini(_private_file);
        ConfigIniFile secrets_ini(_secrets_file);
        ConfigIniFile favs_ini(_favs_file);

        IniFileVersion generic_version = LoadVersionFromConfig(generic_ini);

        /* If we newly create the private/secrets file, add a dummy group on top
         * just so we can add a comment before it (that is how IniFile works).
         * This to explain what the file is about. After doing it once, never touch
         * it again, as otherwise we might be reverting user changes. */
        if (IniGroup *group = private_ini.GetGroup("private"); group != nullptr) group->comment = "; This file possibly contains private information which can identify you as person.\n";
        if (IniGroup *group = secrets_ini.GetGroup("secrets"); group != nullptr) group->comment = "; Do not share this file with others, not even if they claim to be technical support.\n; This file contains saved passwords and other secrets that should remain private to you!\n";

        if (generic_version == IFV_0) {
                /* Remove some obsolete groups. These have all been loaded into other groups. */
                generic_ini.RemoveGroup("patches");
                generic_ini.RemoveGroup("yapf");
                generic_ini.RemoveGroup("gameopt");

                /* Remove all settings from the generic ini that are now in the private ini. */
                generic_ini.RemoveGroup("server_bind_addresses");
                generic_ini.RemoveGroup("servers");
                generic_ini.RemoveGroup("bans");
                for (auto &table : PrivateSettingTables()) {
                        RemoveEntriesFromIni(generic_ini, table);
                }

                /* Remove all settings from the generic ini that are now in the secrets ini. */
                for (auto &table : SecretSettingTables()) {
                        RemoveEntriesFromIni(generic_ini, table);
                }
        }

        if (generic_version < IFV_REMOVE_GENERATION_SEED) {
                IniGroup *game_creation = generic_ini.GetGroup("game_creation");
                if (game_creation != nullptr) {
                        game_creation->RemoveItem("generation_seed");
                }
        }

        /* These variables are migrated from generic ini to private ini now. */
        if (generic_version < IFV_NETWORK_PRIVATE_SETTINGS) {
                IniGroup *network = generic_ini.GetGroup("network");
                if (network != nullptr) {
                        network->RemoveItem("use_relay_service");
                }
        }

        HandleSettingDescs(generic_ini, private_ini, secrets_ini, IniSaveSettings, IniSaveSettingList);
        GraphicsSetSaveConfig(generic_ini);
        GRFSaveConfig(generic_ini, "newgrf", _grfconfig_newgame);
        GRFSaveConfig(generic_ini, "newgrf-static", _grfconfig_static);
        AISaveConfig(generic_ini, "ai_players");
        GameSaveConfig(generic_ini, "game_scripts");
        PickerSaveConfig(favs_ini);

        SaveVersionInConfig(generic_ini);
        SaveVersionInConfig(private_ini);
        SaveVersionInConfig(secrets_ini);
        SaveVersionInConfig(favs_ini);

        generic_ini.SaveToDisk(_config_file);
        private_ini.SaveToDisk(_private_file);
        secrets_ini.SaveToDisk(_secrets_file);
        favs_ini.SaveToDisk(_favs_file);
}

/**
 * Get the list of known NewGrf presets.
 * @returns List of preset names.
 */
StringList GetGRFPresetList()
{
        StringList list;

        ConfigIniFile ini(_config_file);
        for (const IniGroup &group : ini.groups) {
                if (group.name.compare(0, 7, "preset-") == 0) {
                        list.push_back(group.name.substr(7));
                }
        }

        return list;
}

/**
 * Load a NewGRF configuration by preset-name.
 * @param config_name Name of the preset.
 * @return NewGRF configuration.
 * @see GetGRFPresetList
 */
GRFConfig *LoadGRFPresetFromConfig(const char *config_name)
{
        std::string section("preset-");
        section += config_name;

        ConfigIniFile ini(_config_file);
        GRFConfig *config = GRFLoadConfig(ini, section.c_str(), false);

        return config;
}

/**
 * Save a NewGRF configuration with a preset name.
 * @param config_name Name of the preset.
 * @param config      NewGRF configuration to save.
 * @see GetGRFPresetList
 */
void SaveGRFPresetToConfig(const char *config_name, GRFConfig *config)
{
        std::string section("preset-");
        section += config_name;

        ConfigIniFile ini(_config_file);
        GRFSaveConfig(ini, section.c_str(), config);
        ini.SaveToDisk(_config_file);
}

/**
 * Delete a NewGRF configuration by preset name.
 * @param config_name Name of the preset.
 */
void DeleteGRFPresetFromConfig(const char *config_name)
{
        std::string section("preset-");
        section += config_name;

        ConfigIniFile ini(_config_file);
        ini.RemoveGroup(section);
        ini.SaveToDisk(_config_file);
}

/**
 * Handle changing a value. This performs validation of the input value and
 * calls the appropriate callbacks, and saves it when the value is changed.
 * @param object The object the setting is in.
 * @param newval The new value for the setting.
 */
void IntSettingDesc::ChangeValue(const void *object, int32_t newval) const
{
        int32_t oldval = this->Read(object);
        this->MakeValueValid(newval);
        if (this->pre_check != nullptr && !this->pre_check(newval)) return;
        if (oldval == newval) return;

        this->Write(object, newval);
        if (this->post_callback != nullptr) this->post_callback(newval);

        if (this->flags & SF_NO_NETWORK) {
                _gamelog.StartAction(GLAT_SETTING);
                _gamelog.Setting(this->GetName(), oldval, newval);
                _gamelog.StopAction();
        }

        SetWindowClassesDirty(WC_GAME_OPTIONS);

        if (_save_config) SaveToConfig();
}

/**
 * Given a name of setting, return a setting description from the table.
 * @param name Name of the setting to return a setting description of.
 * @param settings Table to look in for the setting.
 * @return Pointer to the setting description of setting \a name if it can be found,
 *         \c nullptr indicates failure to obtain the description.
 */
static const SettingDesc *GetSettingFromName(const std::string_view name, const SettingTable &settings)
{
        /* First check all full names */
        for (auto &desc : settings) {
                const SettingDesc *sd = GetSettingDesc(desc);
                if (!SlIsObjectCurrentlyValid(sd->save.version_from, sd->save.version_to)) continue;
                if (sd->GetName() == name) return sd;
        }

        /* Then check the shortcut variant of the name. */
        std::string short_name_suffix = std::string{ "." }.append(name);
        for (auto &desc : settings) {
                const SettingDesc *sd = GetSettingDesc(desc);
                if (!SlIsObjectCurrentlyValid(sd->save.version_from, sd->save.version_to)) continue;
                if (sd->GetName().ends_with(short_name_suffix)) return sd;
        }

        return nullptr;
}

/**
 * Get the SaveLoad for all settings in the settings table.
 * @param settings The settings table to get the SaveLoad objects from.
 * @param saveloads A vector to store the result in.
 */
void GetSaveLoadFromSettingTable(SettingTable settings, std::vector<SaveLoad> &saveloads)
{
        for (auto &desc : settings) {
                const SettingDesc *sd = GetSettingDesc(desc);
                if (!SlIsObjectCurrentlyValid(sd->save.version_from, sd->save.version_to)) continue;
                saveloads.push_back(sd->save);
        }
}

/**
 * Given a name of setting, return a company setting description of it.
 * @param name  Name of the company setting to return a setting description of.
 * @return Pointer to the setting description of setting \a name if it can be found,
 *         \c nullptr indicates failure to obtain the description.
 */
static const SettingDesc *GetCompanySettingFromName(std::string_view name)
{
        static const std::string_view company_prefix = "company.";
        if (name.starts_with(company_prefix)) name.remove_prefix(company_prefix.size());
        return GetSettingFromName(name, _company_settings);
}

/**
 * Given a name of any setting, return any setting description of it.
 * @param name  Name of the setting to return a setting description of.
 * @return Pointer to the setting description of setting \a name if it can be found,
 *         \c nullptr indicates failure to obtain the description.
 */
const SettingDesc *GetSettingFromName(const std::string_view name)
{
        for (auto &table : GenericSettingTables()) {
                auto sd = GetSettingFromName(name, table);
                if (sd != nullptr) return sd;
        }
        for (auto &table : PrivateSettingTables()) {
                auto sd = GetSettingFromName(name, table);
                if (sd != nullptr) return sd;
        }
        for (auto &table : SecretSettingTables()) {
                auto sd = GetSettingFromName(name, table);
                if (sd != nullptr) return sd;
        }

        return GetCompanySettingFromName(name);
}

/**
 * Network-safe changing of settings (server-only).
 * @param flags operation to perform
 * @param name the name of the setting to change
 * @param value the new value for the setting
 * The new value is properly clamped to its minimum/maximum when setting
 * @return the cost of this operation or an error
 * @see _settings
 */
CommandCost CmdChangeSetting(DoCommandFlag flags, const std::string &name, int32_t value)
{
        if (name.empty()) return CMD_ERROR;
        const SettingDesc *sd = GetSettingFromName(name);

        if (sd == nullptr) return CMD_ERROR;
        if (!SlIsObjectCurrentlyValid(sd->save.version_from, sd->save.version_to)) return CMD_ERROR;
        if (!sd->IsIntSetting()) return CMD_ERROR;

        if (!sd->IsEditable(true)) return CMD_ERROR;

        if (flags & DC_EXEC) {
                sd->AsIntSetting()->ChangeValue(&GetGameSettings(), value);
        }

        return CommandCost();
}

/**
 * Change one of the per-company settings.
 * @param flags operation to perform
 * @param name the name of the company setting to change
 * @param value the new value for the setting
 * The new value is properly clamped to its minimum/maximum when setting
 * @return the cost of this operation or an error
 */
CommandCost CmdChangeCompanySetting(DoCommandFlag flags, const std::string &name, int32_t value)
{
        if (name.empty()) return CMD_ERROR;
        const SettingDesc *sd = GetCompanySettingFromName(name);

        if (sd == nullptr) return CMD_ERROR;
        if (!sd->IsIntSetting()) return CMD_ERROR;

        if (flags & DC_EXEC) {
                sd->AsIntSetting()->ChangeValue(&Company::Get(_current_company)->settings, value);
        }

        return CommandCost();
}

/**
 * Top function to save the new value of an element of the Settings struct
 * @param index offset in the SettingDesc array of the Settings struct which
 * identifies the setting member we want to change
 * @param value new value of the setting
 * @param force_newgame force the newgame settings
 */
bool SetSettingValue(const IntSettingDesc *sd, int32_t value, bool force_newgame)
{
        const IntSettingDesc *setting = sd->AsIntSetting();
        if ((setting->flags & SF_PER_COMPANY) != 0) {
                if (Company::IsValidID(_local_company) && _game_mode != GM_MENU) {
                        return Command<CMD_CHANGE_COMPANY_SETTING>::Post(setting->GetName(), value);
                }

                setting->ChangeValue(&_settings_client.company, value);
                return true;
        }

        /* If an item is company-based, we do not send it over the network
         * (if any) to change. Also *hack*hack* we update the _newgame version
         * of settings because changing a company-based setting in a game also
         * changes its defaults. At least that is the convention we have chosen */
        if (setting->flags & SF_NO_NETWORK_SYNC) {
                if (_game_mode != GM_MENU) {
                        setting->ChangeValue(&_settings_newgame, value);
                }
                setting->ChangeValue(&GetGameSettings(), value);
                return true;
        }

        if (force_newgame) {
                setting->ChangeValue(&_settings_newgame, value);
                return true;
        }

        /* send non-company-based settings over the network */
        if (!_networking || (_networking && _network_server)) {
                return Command<CMD_CHANGE_SETTING>::Post(setting->GetName(), value);
        }
        return false;
}

/**
 * Set the company settings for a new company to their default values.
 */
void SetDefaultCompanySettings(CompanyID cid)
{
        Company *c = Company::Get(cid);
        for (auto &desc : _company_settings) {
                const IntSettingDesc *int_setting = GetSettingDesc(desc)->AsIntSetting();
                int_setting->MakeValueValidAndWrite(&c->settings, int_setting->def);
        }
}

/**
 * Sync all company settings in a multiplayer game.
 */
void SyncCompanySettings()
{
        const void *old_object = &Company::Get(_current_company)->settings;
        const void *new_object = &_settings_client.company;
        for (auto &desc : _company_settings) {
                const SettingDesc *sd = GetSettingDesc(desc);
                uint32_t old_value = (uint32_t)sd->AsIntSetting()->Read(old_object);
                uint32_t new_value = (uint32_t)sd->AsIntSetting()->Read(new_object);
                /*
                 * This is called from a command, and since it contains local configuration information
                 * that the rest of the clients do not know about, we need to circumvent the normal ::Post
                 * local command validation and immediately send the command to the server.
                 */
                if (old_value != new_value) Command<CMD_CHANGE_COMPANY_SETTING>::SendNet(STR_NULL, _local_company, sd->GetName(), new_value);
        }
}

/**
 * Set a setting value with a string.
 * @param sd the setting to change.
 * @param value the value to write
 * @param force_newgame force the newgame settings
 * @note Strings WILL NOT be synced over the network
 */
bool SetSettingValue(const StringSettingDesc *sd, std::string value, bool force_newgame)
{
        assert(sd->flags & SF_NO_NETWORK_SYNC);

        if (GetVarMemType(sd->save.conv) == SLE_VAR_STRQ && value.compare("(null)") == 0) {
                value.clear();
        }

        const void *object = (_game_mode == GM_MENU || force_newgame) ? &_settings_newgame : &_settings_game;
        sd->AsStringSetting()->ChangeValue(object, value);
        return true;
}

/**
 * Handle changing a string value. This performs validation of the input value
 * and calls the appropriate callbacks, and saves it when the value is changed.
 * @param object The object the setting is in.
 * @param newval The new value for the setting.
 */
void StringSettingDesc::ChangeValue(const void *object, std::string &newval) const
{
        this->MakeValueValid(newval);
        if (this->pre_check != nullptr && !this->pre_check(newval)) return;

        this->Write(object, newval);
        if (this->post_callback != nullptr) this->post_callback(newval);

        if (_save_config) SaveToConfig();
}

/* Those 2 functions need to be here, else we have to make some stuff non-static
 * and besides, it is also better to keep stuff like this at the same place */
void IConsoleSetSetting(const char *name, const char *value, bool force_newgame)
{
        const SettingDesc *sd = GetSettingFromName(name);
        if (sd == nullptr) {
                IConsolePrint(CC_ERROR, "'{}' is an unknown setting.", name);
                return;
        }

        bool success = true;
        if (sd->IsStringSetting()) {
                success = SetSettingValue(sd->AsStringSetting(), value, force_newgame);
        } else if (sd->IsIntSetting()) {
                const IntSettingDesc *isd = sd->AsIntSetting();
                size_t val = isd->ParseValue(value);
                if (!_settings_error_list.empty()) {
                        IConsolePrint(CC_ERROR, "'{}' is not a valid value for this setting.", value);
                        _settings_error_list.clear();
                        return;
                }
                success = SetSettingValue(isd, (int32_t)val, force_newgame);
        }

        if (!success) {
                if (_network_server) {
                        IConsolePrint(CC_ERROR, "This command/variable is not available during network games.");
                } else {
                        IConsolePrint(CC_ERROR, "This command/variable is only available to a network server.");
                }
        }
}

void IConsoleSetSetting(const char *name, int value)
{
        const SettingDesc *sd = GetSettingFromName(name);
        assert(sd != nullptr);
        SetSettingValue(sd->AsIntSetting(), value);
}

/**
 * Output value of a specific setting to the console
 * @param name  Name of the setting to output its value
 * @param force_newgame force the newgame settings
 */
void IConsoleGetSetting(const char *name, bool force_newgame)
{
        const SettingDesc *sd = GetSettingFromName(name);
        if (sd == nullptr) {
                IConsolePrint(CC_ERROR, "'{}' is an unknown setting.", name);
                return;
        }

        const void *object = (_game_mode == GM_MENU || force_newgame) ? &_settings_newgame : &_settings_game;

        if (sd->IsStringSetting()) {
                IConsolePrint(CC_INFO, "Current value for '{}' is '{}'.", sd->GetName(), sd->AsStringSetting()->Read(object));
        } else if (sd->IsIntSetting()) {
                std::string value = sd->FormatValue(object);
                const IntSettingDesc *int_setting = sd->AsIntSetting();
                IConsolePrint(CC_INFO, "Current value for '{}' is '{}' (min: {}{}, max: {}).",
                        sd->GetName(), value, (sd->flags & SF_GUI_0_IS_SPECIAL) ? "(0) " : "", int_setting->min, int_setting->max);
        }
}

static void IConsoleListSettingsTable(const SettingTable &table, const char *prefilter)
{
        for (auto &desc : table) {
                const SettingDesc *sd = GetSettingDesc(desc);
                if (!SlIsObjectCurrentlyValid(sd->save.version_from, sd->save.version_to)) continue;
                if (prefilter != nullptr && sd->GetName().find(prefilter) == std::string::npos) continue;
                IConsolePrint(CC_DEFAULT, "{} = {}", sd->GetName(), sd->FormatValue(&GetGameSettings()));
        }
}

/**
 * List all settings and their value to the console
 *
 * @param prefilter  If not \c nullptr, only list settings with names that begin with \a prefilter prefix
 */
void IConsoleListSettings(const char *prefilter)
{
        IConsolePrint(CC_HELP, "All settings with their current value:");

        for (auto &table : GenericSettingTables()) {
                IConsoleListSettingsTable(table, prefilter);
        }
        for (auto &table : PrivateSettingTables()) {
                IConsoleListSettingsTable(table, prefilter);
        }
        for (auto &table : SecretSettingTables()) {
                IConsoleListSettingsTable(table, prefilter);
        }

        IConsolePrint(CC_HELP, "Use 'setting' command to change a value.");
}