settings_gui.cpp

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/*
 * 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/>.
 */
 
#include "stdafx.h"
#include "currency.h"
#include "error.h"
#include "settings_gui.h"
#include "textbuf_gui.h"
#include "command_func.h"
#include "network/network.h"
#include "town.h"
#include "settings_internal.h"
#include "newgrf_townname.h"
#include "strings_func.h"
#include "window_func.h"
#include "string_func.h"
#include "widgets/dropdown_type.h"
#include "widgets/dropdown_func.h"
#include "highscore.h"
#include "base_media_base.h"
#include "company_base.h"
#include "company_func.h"
#include "viewport_func.h"
#include "core/geometry_func.hpp"
#include "ai/ai.hpp"
#include "blitter/factory.hpp"
#include "language.h"
#include "textfile_gui.h"
#include "stringfilter_type.h"
#include "querystring_gui.h"
#include "fontcache.h"
#include "zoom_func.h"
 
#include <vector>
 
#include "safeguards.h"
 
 
static const StringID _driveside_dropdown[] = {
  STR_GAME_OPTIONS_ROAD_VEHICLES_DROPDOWN_LEFT,
  STR_GAME_OPTIONS_ROAD_VEHICLES_DROPDOWN_RIGHT,
  INVALID_STRING_ID
};
 
static const StringID _autosave_dropdown[] = {
  STR_GAME_OPTIONS_AUTOSAVE_DROPDOWN_OFF,
  STR_GAME_OPTIONS_AUTOSAVE_DROPDOWN_EVERY_1_MONTH,
  STR_GAME_OPTIONS_AUTOSAVE_DROPDOWN_EVERY_3_MONTHS,
  STR_GAME_OPTIONS_AUTOSAVE_DROPDOWN_EVERY_6_MONTHS,
  STR_GAME_OPTIONS_AUTOSAVE_DROPDOWN_EVERY_12_MONTHS,
  INVALID_STRING_ID,
};
 
static const StringID _gui_zoom_dropdown[] = {
  STR_GAME_OPTIONS_GUI_ZOOM_DROPDOWN_NORMAL,
  STR_GAME_OPTIONS_GUI_ZOOM_DROPDOWN_2X_ZOOM,
  STR_GAME_OPTIONS_GUI_ZOOM_DROPDOWN_4X_ZOOM,
  INVALID_STRING_ID,
};
 
static const StringID _font_zoom_dropdown[] = {
  STR_GAME_OPTIONS_FONT_ZOOM_DROPDOWN_NORMAL,
  STR_GAME_OPTIONS_FONT_ZOOM_DROPDOWN_2X_ZOOM,
  STR_GAME_OPTIONS_FONT_ZOOM_DROPDOWN_4X_ZOOM,
  INVALID_STRING_ID,
};
 
int _nb_orig_names = SPECSTR_TOWNNAME_LAST - SPECSTR_TOWNNAME_START + 1; 
static StringID *_grf_names = nullptr; 
static int _nb_grf_names = 0;       
 
static Dimension _circle_size; 
 
static const void *ResolveVariableAddress(const GameSettings *settings_ptr, const SettingDesc *sd);
 
void InitGRFTownGeneratorNames()
{
  free(_grf_names);
  _grf_names = GetGRFTownNameList();
  _nb_grf_names = 0;
  for (StringID *s = _grf_names; *s != INVALID_STRING_ID; s++) _nb_grf_names++;
}
 
static inline StringID TownName(int town_name)
{
  if (town_name < _nb_orig_names) return STR_GAME_OPTIONS_TOWN_NAME_ORIGINAL_ENGLISH + town_name;
  town_name -= _nb_orig_names;
  if (town_name < _nb_grf_names) return _grf_names[town_name];
  return STR_UNDEFINED;
}
 
static uint GetCurRes()
{
  uint i;
 
  for (i = 0; i != _resolutions.size(); i++) {
    if (_resolutions[i] == Dimension(_screen.width, _screen.height)) break;
  }
  return i;
}
 
static void ShowCustCurrency();
 
template <class T>
static DropDownList BuildSetDropDownList(int *selected_index, bool allow_selection)
{
  int n = T::GetNumSets();
  *selected_index = T::GetIndexOfUsedSet();
 
  DropDownList list;
  for (int i = 0; i < n; i++) {
    list.emplace_back(new DropDownListCharStringItem(T::GetSet(i)->name, i, !allow_selection && (*selected_index != i)));
  }
 
  return list;
}
 
DropDownList BuildMusicSetDropDownList(int *selected_index)
{
  return BuildSetDropDownList<BaseMusic>(selected_index, true);
}
 
template <class TBaseSet>
struct BaseSetTextfileWindow : public TextfileWindow {
  const TBaseSet* baseset; 
  StringID content_type;   
 
  BaseSetTextfileWindow(TextfileType file_type, const TBaseSet* baseset, StringID content_type) : TextfileWindow(file_type), baseset(baseset), content_type(content_type)
  {
    const char *textfile = this->baseset->GetTextfile(file_type);
    this->LoadTextfile(textfile, BASESET_DIR);
  }
 
  void SetStringParameters(int widget) const override
  {
    if (widget == WID_TF_CAPTION) {
      SetDParam(0, content_type);
      SetDParamStr(1, this->baseset->name.c_str());
    }
  }
};
 
template <class TBaseSet>
void ShowBaseSetTextfileWindow(TextfileType file_type, const TBaseSet* baseset, StringID content_type)
{
  DeleteWindowById(WC_TEXTFILE, file_type);
  new BaseSetTextfileWindow<TBaseSet>(file_type, baseset, content_type);
}
 
struct GameOptionsWindow : Window {
  GameSettings *opt;
  bool reload;
 
  GameOptionsWindow(WindowDesc *desc) : Window(desc)
  {
    this->opt = &GetGameSettings();
    this->reload = false;
 
    this->InitNested(WN_GAME_OPTIONS_GAME_OPTIONS);
    this->OnInvalidateData(0);
  }
 
  ~GameOptionsWindow()
  {
    DeleteWindowById(WC_CUSTOM_CURRENCY, 0);
    DeleteWindowByClass(WC_TEXTFILE);
    if (this->reload) _switch_mode = SM_MENU;
  }
 
  DropDownList BuildDropDownList(int widget, int *selected_index) const
  {
    DropDownList list;
    switch (widget) {
      case WID_GO_CURRENCY_DROPDOWN: { // Setup currencies dropdown
        *selected_index = this->opt->locale.currency;
        StringID *items = BuildCurrencyDropdown();
        uint64 disabled = _game_mode == GM_MENU ? 0LL : ~GetMaskOfAllowedCurrencies();
 
        /* Add non-custom currencies; sorted naturally */
        for (uint i = 0; i < CURRENCY_END; items++, i++) {
          if (i == CURRENCY_CUSTOM) continue;
          list.emplace_back(new DropDownListStringItem(*items, i, HasBit(disabled, i)));
        }
        std::sort(list.begin(), list.end(), DropDownListStringItem::NatSortFunc);
 
        /* Append custom currency at the end */
        list.emplace_back(new DropDownListItem(-1, false)); // separator line
        list.emplace_back(new DropDownListStringItem(STR_GAME_OPTIONS_CURRENCY_CUSTOM, CURRENCY_CUSTOM, HasBit(disabled, CURRENCY_CUSTOM)));
        break;
      }
 
      case WID_GO_ROADSIDE_DROPDOWN: { // Setup road-side dropdown
        *selected_index = this->opt->vehicle.road_side;
        const StringID *items = _driveside_dropdown;
        uint disabled = 0;
 
        /* You can only change the drive side if you are in the menu or ingame with
         * no vehicles present. In a networking game only the server can change it */
        extern bool RoadVehiclesAreBuilt();
        if ((_game_mode != GM_MENU && RoadVehiclesAreBuilt()) || (_networking && !_network_server)) {
          disabled = ~(1 << this->opt->vehicle.road_side); // disable the other value
        }
 
        for (uint i = 0; *items != INVALID_STRING_ID; items++, i++) {
          list.emplace_back(new DropDownListStringItem(*items, i, HasBit(disabled, i)));
        }
        break;
      }
 
      case WID_GO_TOWNNAME_DROPDOWN: { // Setup townname dropdown
        *selected_index = this->opt->game_creation.town_name;
 
        int enabled_item = (_game_mode == GM_MENU || Town::GetNumItems() == 0) ? -1 : *selected_index;
 
        /* Add and sort newgrf townnames generators */
        for (int i = 0; i < _nb_grf_names; i++) {
          int result = _nb_orig_names + i;
          list.emplace_back(new DropDownListStringItem(_grf_names[i], result, enabled_item != result && enabled_item >= 0));
        }
        std::sort(list.begin(), list.end(), DropDownListStringItem::NatSortFunc);
 
        size_t newgrf_size = list.size();
        /* Insert newgrf_names at the top of the list */
        if (newgrf_size > 0) {
          list.emplace_back(new DropDownListItem(-1, false)); // separator line
          newgrf_size++;
        }
 
        /* Add and sort original townnames generators */
        for (int i = 0; i < _nb_orig_names; i++) {
          list.emplace_back(new DropDownListStringItem(STR_GAME_OPTIONS_TOWN_NAME_ORIGINAL_ENGLISH + i, i, enabled_item != i && enabled_item >= 0));
        }
        std::sort(list.begin() + newgrf_size, list.end(), DropDownListStringItem::NatSortFunc);
        break;
      }
 
      case WID_GO_AUTOSAVE_DROPDOWN: { // Setup autosave dropdown
        *selected_index = _settings_client.gui.autosave;
        const StringID *items = _autosave_dropdown;
        for (uint i = 0; *items != INVALID_STRING_ID; items++, i++) {
          list.emplace_back(new DropDownListStringItem(*items, i, false));
        }
        break;
      }
 
      case WID_GO_LANG_DROPDOWN: { // Setup interface language dropdown
        for (uint i = 0; i < _languages.size(); i++) {
          if (&_languages[i] == _current_language) *selected_index = i;
          list.emplace_back(new DropDownListStringItem(SPECSTR_LANGUAGE_START + i, i, false));
        }
        std::sort(list.begin(), list.end(), DropDownListStringItem::NatSortFunc);
        break;
      }
 
      case WID_GO_RESOLUTION_DROPDOWN: // Setup resolution dropdown
        if (_resolutions.empty()) break;
 
        *selected_index = GetCurRes();
        for (uint i = 0; i < _resolutions.size(); i++) {
          list.emplace_back(new DropDownListStringItem(SPECSTR_RESOLUTION_START + i, i, false));
        }
        break;
 
      case WID_GO_GUI_ZOOM_DROPDOWN: {
        *selected_index = ZOOM_LVL_OUT_4X - _gui_zoom;
        const StringID *items = _gui_zoom_dropdown;
        for (int i = 0; *items != INVALID_STRING_ID; items++, i++) {
          list.emplace_back(new DropDownListStringItem(*items, i, _settings_client.gui.zoom_min > ZOOM_LVL_OUT_4X - i));
        }
        break;
      }
 
      case WID_GO_FONT_ZOOM_DROPDOWN: {
        *selected_index = ZOOM_LVL_OUT_4X - _font_zoom;
        const StringID *items = _font_zoom_dropdown;
        for (int i = 0; *items != INVALID_STRING_ID; items++, i++) {
          list.emplace_back(new DropDownListStringItem(*items, i, false));
        }
        break;
      }
 
      case WID_GO_BASE_GRF_DROPDOWN:
        list = BuildSetDropDownList<BaseGraphics>(selected_index, (_game_mode == GM_MENU));
        break;
 
      case WID_GO_BASE_SFX_DROPDOWN:
        list = BuildSetDropDownList<BaseSounds>(selected_index, (_game_mode == GM_MENU));
        break;
 
      case WID_GO_BASE_MUSIC_DROPDOWN:
        list = BuildMusicSetDropDownList(selected_index);
        break;
    }
 
    return list;
  }
 
  void SetStringParameters(int widget) const override
  {
    switch (widget) {
      case WID_GO_CURRENCY_DROPDOWN:   SetDParam(0, _currency_specs[this->opt->locale.currency].name); break;
      case WID_GO_ROADSIDE_DROPDOWN:   SetDParam(0, STR_GAME_OPTIONS_ROAD_VEHICLES_DROPDOWN_LEFT + this->opt->vehicle.road_side); break;
      case WID_GO_TOWNNAME_DROPDOWN:   SetDParam(0, TownName(this->opt->game_creation.town_name)); break;
      case WID_GO_AUTOSAVE_DROPDOWN:   SetDParam(0, _autosave_dropdown[_settings_client.gui.autosave]); break;
      case WID_GO_LANG_DROPDOWN:       SetDParamStr(0, _current_language->own_name); break;
      case WID_GO_RESOLUTION_DROPDOWN: SetDParam(0, GetCurRes() == _resolutions.size() ? STR_GAME_OPTIONS_RESOLUTION_OTHER : SPECSTR_RESOLUTION_START + GetCurRes()); break;
      case WID_GO_GUI_ZOOM_DROPDOWN:   SetDParam(0, _gui_zoom_dropdown[ZOOM_LVL_OUT_4X - _gui_zoom]); break;
      case WID_GO_FONT_ZOOM_DROPDOWN:  SetDParam(0, _font_zoom_dropdown[ZOOM_LVL_OUT_4X - _font_zoom]); break;
      case WID_GO_BASE_GRF_DROPDOWN:   SetDParamStr(0, BaseGraphics::GetUsedSet()->name.c_str()); break;
      case WID_GO_BASE_GRF_STATUS:     SetDParam(0, BaseGraphics::GetUsedSet()->GetNumInvalid()); break;
      case WID_GO_BASE_SFX_DROPDOWN:   SetDParamStr(0, BaseSounds::GetUsedSet()->name.c_str()); break;
      case WID_GO_BASE_MUSIC_DROPDOWN: SetDParamStr(0, BaseMusic::GetUsedSet()->name.c_str()); break;
      case WID_GO_BASE_MUSIC_STATUS:   SetDParam(0, BaseMusic::GetUsedSet()->GetNumInvalid()); break;
    }
  }
 
  void DrawWidget(const Rect &r, int widget) const override
  {
    switch (widget) {
      case WID_GO_BASE_GRF_DESCRIPTION:
        SetDParamStr(0, BaseGraphics::GetUsedSet()->GetDescription(GetCurrentLanguageIsoCode()));
        DrawStringMultiLine(r.left, r.right, r.top, UINT16_MAX, STR_BLACK_RAW_STRING);
        break;
 
      case WID_GO_BASE_SFX_DESCRIPTION:
        SetDParamStr(0, BaseSounds::GetUsedSet()->GetDescription(GetCurrentLanguageIsoCode()));
        DrawStringMultiLine(r.left, r.right, r.top, UINT16_MAX, STR_BLACK_RAW_STRING);
        break;
 
      case WID_GO_BASE_MUSIC_DESCRIPTION:
        SetDParamStr(0, BaseMusic::GetUsedSet()->GetDescription(GetCurrentLanguageIsoCode()));
        DrawStringMultiLine(r.left, r.right, r.top, UINT16_MAX, STR_BLACK_RAW_STRING);
        break;
    }
  }
 
  void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize) override
  {
    switch (widget) {
      case WID_GO_BASE_GRF_DESCRIPTION:
        /* Find the biggest description for the default size. */
        for (int i = 0; i < BaseGraphics::GetNumSets(); i++) {
          SetDParamStr(0, BaseGraphics::GetSet(i)->GetDescription(GetCurrentLanguageIsoCode()));
          size->height = std::max(size->height, (uint)GetStringHeight(STR_BLACK_RAW_STRING, size->width));
        }
        break;
 
      case WID_GO_BASE_GRF_STATUS:
        /* Find the biggest description for the default size. */
        for (int i = 0; i < BaseGraphics::GetNumSets(); i++) {
          uint invalid_files = BaseGraphics::GetSet(i)->GetNumInvalid();
          if (invalid_files == 0) continue;
 
          SetDParam(0, invalid_files);
          *size = maxdim(*size, GetStringBoundingBox(STR_GAME_OPTIONS_BASE_GRF_STATUS));
        }
        break;
 
      case WID_GO_BASE_SFX_DESCRIPTION:
        /* Find the biggest description for the default size. */
        for (int i = 0; i < BaseSounds::GetNumSets(); i++) {
          SetDParamStr(0, BaseSounds::GetSet(i)->GetDescription(GetCurrentLanguageIsoCode()));
          size->height = std::max(size->height, (uint)GetStringHeight(STR_BLACK_RAW_STRING, size->width));
        }
        break;
 
      case WID_GO_BASE_MUSIC_DESCRIPTION:
        /* Find the biggest description for the default size. */
        for (int i = 0; i < BaseMusic::GetNumSets(); i++) {
          SetDParamStr(0, BaseMusic::GetSet(i)->GetDescription(GetCurrentLanguageIsoCode()));
          size->height = std::max(size->height, (uint)GetStringHeight(STR_BLACK_RAW_STRING, size->width));
        }
        break;
 
      case WID_GO_BASE_MUSIC_STATUS:
        /* Find the biggest description for the default size. */
        for (int i = 0; i < BaseMusic::GetNumSets(); i++) {
          uint invalid_files = BaseMusic::GetSet(i)->GetNumInvalid();
          if (invalid_files == 0) continue;
 
          SetDParam(0, invalid_files);
          *size = maxdim(*size, GetStringBoundingBox(STR_GAME_OPTIONS_BASE_MUSIC_STATUS));
        }
        break;
 
      default: {
        int selected;
        DropDownList list = this->BuildDropDownList(widget, &selected);
        if (!list.empty()) {
          /* Find the biggest item for the default size. */
          for (const auto &ddli : list) {
            Dimension string_dim;
            int width = ddli->Width();
            string_dim.width = width + padding.width;
            string_dim.height = ddli->Height(width) + padding.height;
            *size = maxdim(*size, string_dim);
          }
        }
      }
    }
  }
 
  void OnClick(Point pt, int widget, int click_count) override
  {
    if (widget >= WID_GO_BASE_GRF_TEXTFILE && widget < WID_GO_BASE_GRF_TEXTFILE + TFT_END) {
      if (BaseGraphics::GetUsedSet() == nullptr) return;
 
      ShowBaseSetTextfileWindow((TextfileType)(widget - WID_GO_BASE_GRF_TEXTFILE), BaseGraphics::GetUsedSet(), STR_CONTENT_TYPE_BASE_GRAPHICS);
      return;
    }
    if (widget >= WID_GO_BASE_SFX_TEXTFILE && widget < WID_GO_BASE_SFX_TEXTFILE + TFT_END) {
      if (BaseSounds::GetUsedSet() == nullptr) return;
 
      ShowBaseSetTextfileWindow((TextfileType)(widget - WID_GO_BASE_SFX_TEXTFILE), BaseSounds::GetUsedSet(), STR_CONTENT_TYPE_BASE_SOUNDS);
      return;
    }
    if (widget >= WID_GO_BASE_MUSIC_TEXTFILE && widget < WID_GO_BASE_MUSIC_TEXTFILE + TFT_END) {
      if (BaseMusic::GetUsedSet() == nullptr) return;
 
      ShowBaseSetTextfileWindow((TextfileType)(widget - WID_GO_BASE_MUSIC_TEXTFILE), BaseMusic::GetUsedSet(), STR_CONTENT_TYPE_BASE_MUSIC);
      return;
    }
    switch (widget) {
      case WID_GO_FULLSCREEN_BUTTON: // Click fullscreen on/off
        /* try to toggle full-screen on/off */
        if (!ToggleFullScreen(!_fullscreen)) {
          ShowErrorMessage(STR_ERROR_FULLSCREEN_FAILED, INVALID_STRING_ID, WL_ERROR);
        }
        this->SetWidgetLoweredState(WID_GO_FULLSCREEN_BUTTON, _fullscreen);
        this->SetDirty();
        break;
 
      default: {
        int selected;
        DropDownList list = this->BuildDropDownList(widget, &selected);
        if (!list.empty()) {
          ShowDropDownList(this, std::move(list), selected, widget);
        } else {
          if (widget == WID_GO_RESOLUTION_DROPDOWN) ShowErrorMessage(STR_ERROR_RESOLUTION_LIST_FAILED, INVALID_STRING_ID, WL_ERROR);
        }
        break;
      }
    }
  }
 
  template <class T>
  void SetMediaSet(int index)
  {
    if (_game_mode == GM_MENU) {
      auto name = T::GetSet(index)->name;
 
      T::ini_set = name;
 
      T::SetSet(name);
      this->reload = true;
      this->InvalidateData();
    }
  }
 
  void OnDropdownSelect(int widget, int index) override
  {
    switch (widget) {
      case WID_GO_CURRENCY_DROPDOWN: // Currency
        if (index == CURRENCY_CUSTOM) ShowCustCurrency();
        this->opt->locale.currency = index;
        ReInitAllWindows();
        break;
 
      case WID_GO_ROADSIDE_DROPDOWN: // Road side
        if (this->opt->vehicle.road_side != index) { // only change if setting changed
          uint i;
          if (GetSettingFromName("vehicle.road_side", &i) == nullptr) NOT_REACHED();
          SetSettingValue(i, index);
          MarkWholeScreenDirty();
        }
        break;
 
      case WID_GO_TOWNNAME_DROPDOWN: // Town names
        if (_game_mode == GM_MENU || Town::GetNumItems() == 0) {
          this->opt->game_creation.town_name = index;
          SetWindowDirty(WC_GAME_OPTIONS, WN_GAME_OPTIONS_GAME_OPTIONS);
        }
        break;
 
      case WID_GO_AUTOSAVE_DROPDOWN: // Autosave options
        _settings_client.gui.autosave = index;
        this->SetDirty();
        break;
 
      case WID_GO_LANG_DROPDOWN: // Change interface language
        ReadLanguagePack(&_languages[index]);
        DeleteWindowByClass(WC_QUERY_STRING);
        CheckForMissingGlyphs();
        ClearAllCachedNames();
        UpdateAllVirtCoords();
        ReInitAllWindows();
        break;
 
      case WID_GO_RESOLUTION_DROPDOWN: // Change resolution
        if ((uint)index < _resolutions.size() && ChangeResInGame(_resolutions[index].width, _resolutions[index].height)) {
          this->SetDirty();
        }
        break;
 
      case WID_GO_GUI_ZOOM_DROPDOWN:
        GfxClearSpriteCache();
        _gui_zoom = (ZoomLevel)(ZOOM_LVL_OUT_4X - index);
        UpdateCursorSize();
        UpdateAllVirtCoords();
        FixTitleGameZoom();
        ReInitAllWindows();
        break;
 
      case WID_GO_FONT_ZOOM_DROPDOWN:
        GfxClearSpriteCache();
        _font_zoom = (ZoomLevel)(ZOOM_LVL_OUT_4X - index);
        ClearFontCache();
        LoadStringWidthTable();
        UpdateAllVirtCoords();
        break;
 
      case WID_GO_BASE_GRF_DROPDOWN:
        this->SetMediaSet<BaseGraphics>(index);
        break;
 
      case WID_GO_BASE_SFX_DROPDOWN:
        this->SetMediaSet<BaseSounds>(index);
        break;
 
      case WID_GO_BASE_MUSIC_DROPDOWN:
        ChangeMusicSet(index);
        break;
    }
  }
 
  void OnInvalidateData(int data = 0, bool gui_scope = true) override
  {
    if (!gui_scope) return;
    this->SetWidgetLoweredState(WID_GO_FULLSCREEN_BUTTON, _fullscreen);
 
    bool missing_files = BaseGraphics::GetUsedSet()->GetNumMissing() == 0;
    this->GetWidget<NWidgetCore>(WID_GO_BASE_GRF_STATUS)->SetDataTip(missing_files ? STR_EMPTY : STR_GAME_OPTIONS_BASE_GRF_STATUS, STR_NULL);
 
    for (TextfileType tft = TFT_BEGIN; tft < TFT_END; tft++) {
      this->SetWidgetDisabledState(WID_GO_BASE_GRF_TEXTFILE + tft, BaseGraphics::GetUsedSet() == nullptr || BaseGraphics::GetUsedSet()->GetTextfile(tft) == nullptr);
      this->SetWidgetDisabledState(WID_GO_BASE_SFX_TEXTFILE + tft, BaseSounds::GetUsedSet() == nullptr || BaseSounds::GetUsedSet()->GetTextfile(tft) == nullptr);
      this->SetWidgetDisabledState(WID_GO_BASE_MUSIC_TEXTFILE + tft, BaseMusic::GetUsedSet() == nullptr || BaseMusic::GetUsedSet()->GetTextfile(tft) == nullptr);
    }
 
    missing_files = BaseMusic::GetUsedSet()->GetNumInvalid() == 0;
    this->GetWidget<NWidgetCore>(WID_GO_BASE_MUSIC_STATUS)->SetDataTip(missing_files ? STR_EMPTY : STR_GAME_OPTIONS_BASE_MUSIC_STATUS, STR_NULL);
  }
};
 
static const NWidgetPart _nested_game_options_widgets[] = {
  NWidget(NWID_HORIZONTAL),
    NWidget(WWT_CLOSEBOX, COLOUR_GREY),
    NWidget(WWT_CAPTION, COLOUR_GREY), SetDataTip(STR_GAME_OPTIONS_CAPTION, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
  EndContainer(),
  NWidget(WWT_PANEL, COLOUR_GREY, WID_GO_BACKGROUND), SetPIP(6, 6, 10),
    NWidget(NWID_HORIZONTAL), SetPIP(10, 10, 10),
      NWidget(NWID_VERTICAL), SetPIP(0, 6, 0),
        NWidget(WWT_FRAME, COLOUR_GREY), SetDataTip(STR_GAME_OPTIONS_ROAD_VEHICLES_FRAME, STR_NULL),
          NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_GO_ROADSIDE_DROPDOWN), SetMinimalSize(150, 12), SetDataTip(STR_BLACK_STRING, STR_GAME_OPTIONS_ROAD_VEHICLES_DROPDOWN_TOOLTIP), SetFill(1, 0),
        EndContainer(),
        NWidget(WWT_FRAME, COLOUR_GREY), SetDataTip(STR_GAME_OPTIONS_AUTOSAVE_FRAME, STR_NULL),
          NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_GO_AUTOSAVE_DROPDOWN), SetMinimalSize(150, 12), SetDataTip(STR_BLACK_STRING, STR_GAME_OPTIONS_AUTOSAVE_DROPDOWN_TOOLTIP), SetFill(1, 0),
        EndContainer(),
        NWidget(WWT_FRAME, COLOUR_GREY), SetDataTip(STR_GAME_OPTIONS_RESOLUTION, STR_NULL),
          NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_GO_RESOLUTION_DROPDOWN), SetMinimalSize(150, 12), SetDataTip(STR_BLACK_STRING, STR_GAME_OPTIONS_RESOLUTION_TOOLTIP), SetFill(1, 0), SetPadding(0, 0, 3, 0),
          NWidget(NWID_HORIZONTAL),
            NWidget(WWT_TEXT, COLOUR_GREY), SetMinimalSize(0, 12), SetFill(1, 0), SetDataTip(STR_GAME_OPTIONS_FULLSCREEN, STR_NULL),
            NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_GO_FULLSCREEN_BUTTON), SetMinimalSize(21, 9), SetDataTip(STR_EMPTY, STR_GAME_OPTIONS_FULLSCREEN_TOOLTIP),
          EndContainer(),
        EndContainer(),
        NWidget(WWT_FRAME, COLOUR_GREY), SetDataTip(STR_GAME_OPTIONS_GUI_ZOOM_FRAME, STR_NULL),
          NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_GO_GUI_ZOOM_DROPDOWN), SetMinimalSize(150, 12), SetDataTip(STR_BLACK_STRING, STR_GAME_OPTIONS_GUI_ZOOM_DROPDOWN_TOOLTIP), SetFill(1, 0),
        EndContainer(),
      EndContainer(),
 
      NWidget(NWID_VERTICAL), SetPIP(0, 6, 0),
        NWidget(WWT_FRAME, COLOUR_GREY), SetDataTip(STR_GAME_OPTIONS_TOWN_NAMES_FRAME, STR_NULL),
          NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_GO_TOWNNAME_DROPDOWN), SetMinimalSize(150, 12), SetDataTip(STR_BLACK_STRING, STR_GAME_OPTIONS_TOWN_NAMES_DROPDOWN_TOOLTIP), SetFill(1, 0),
        EndContainer(),
        NWidget(WWT_FRAME, COLOUR_GREY), SetDataTip(STR_GAME_OPTIONS_LANGUAGE, STR_NULL),
          NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_GO_LANG_DROPDOWN), SetMinimalSize(150, 12), SetDataTip(STR_BLACK_RAW_STRING, STR_GAME_OPTIONS_LANGUAGE_TOOLTIP), SetFill(1, 0),
        EndContainer(),
        NWidget(WWT_FRAME, COLOUR_GREY), SetDataTip(STR_GAME_OPTIONS_CURRENCY_UNITS_FRAME, STR_NULL),
          NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_GO_CURRENCY_DROPDOWN), SetMinimalSize(150, 12), SetDataTip(STR_BLACK_STRING, STR_GAME_OPTIONS_CURRENCY_UNITS_DROPDOWN_TOOLTIP), SetFill(1, 0),
        EndContainer(),
        NWidget(NWID_SPACER), SetMinimalSize(0, 0), SetFill(0, 1),
        NWidget(WWT_FRAME, COLOUR_GREY), SetDataTip(STR_GAME_OPTIONS_FONT_ZOOM, STR_NULL),
          NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_GO_FONT_ZOOM_DROPDOWN), SetMinimalSize(150, 12), SetDataTip(STR_BLACK_STRING, STR_GAME_OPTIONS_FONT_ZOOM_DROPDOWN_TOOLTIP), SetFill(1, 0),
        EndContainer(),
      EndContainer(),
    EndContainer(),
 
    NWidget(WWT_FRAME, COLOUR_GREY), SetDataTip(STR_GAME_OPTIONS_BASE_GRF, STR_NULL), SetPadding(0, 10, 0, 10),
      NWidget(NWID_HORIZONTAL), SetPIP(0, 30, 0),
        NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_GO_BASE_GRF_DROPDOWN), SetMinimalSize(150, 12), SetDataTip(STR_BLACK_RAW_STRING, STR_GAME_OPTIONS_BASE_GRF_TOOLTIP),
        NWidget(WWT_TEXT, COLOUR_GREY, WID_GO_BASE_GRF_STATUS), SetMinimalSize(150, 12), SetDataTip(STR_EMPTY, STR_NULL), SetFill(1, 0),
      EndContainer(),
      NWidget(WWT_TEXT, COLOUR_GREY, WID_GO_BASE_GRF_DESCRIPTION), SetMinimalSize(330, 0), SetDataTip(STR_EMPTY, STR_GAME_OPTIONS_BASE_GRF_DESCRIPTION_TOOLTIP), SetFill(1, 0), SetPadding(6, 0, 6, 0),
      NWidget(NWID_HORIZONTAL, NC_EQUALSIZE), SetPIP(7, 0, 7),
        NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_GO_BASE_GRF_TEXTFILE + TFT_README), SetFill(1, 0), SetResize(1, 0), SetDataTip(STR_TEXTFILE_VIEW_README, STR_NULL),
        NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_GO_BASE_GRF_TEXTFILE + TFT_CHANGELOG), SetFill(1, 0), SetResize(1, 0), SetDataTip(STR_TEXTFILE_VIEW_CHANGELOG, STR_NULL),
        NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_GO_BASE_GRF_TEXTFILE + TFT_LICENSE), SetFill(1, 0), SetResize(1, 0), SetDataTip(STR_TEXTFILE_VIEW_LICENCE, STR_NULL),
      EndContainer(),
    EndContainer(),
 
    NWidget(WWT_FRAME, COLOUR_GREY), SetDataTip(STR_GAME_OPTIONS_BASE_SFX, STR_NULL), SetPadding(0, 10, 0, 10),
      NWidget(NWID_HORIZONTAL), SetPIP(0, 30, 0),
        NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_GO_BASE_SFX_DROPDOWN), SetMinimalSize(150, 12), SetDataTip(STR_BLACK_RAW_STRING, STR_GAME_OPTIONS_BASE_SFX_TOOLTIP),
        NWidget(NWID_SPACER), SetFill(1, 0),
      EndContainer(),
      NWidget(WWT_TEXT, COLOUR_GREY, WID_GO_BASE_SFX_DESCRIPTION), SetMinimalSize(330, 0), SetDataTip(STR_EMPTY, STR_GAME_OPTIONS_BASE_SFX_DESCRIPTION_TOOLTIP), SetFill(1, 0), SetPadding(6, 0, 6, 0),
      NWidget(NWID_HORIZONTAL, NC_EQUALSIZE), SetPIP(7, 0, 7),
        NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_GO_BASE_SFX_TEXTFILE + TFT_README), SetFill(1, 0), SetResize(1, 0), SetDataTip(STR_TEXTFILE_VIEW_README, STR_NULL),
        NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_GO_BASE_SFX_TEXTFILE + TFT_CHANGELOG), SetFill(1, 0), SetResize(1, 0), SetDataTip(STR_TEXTFILE_VIEW_CHANGELOG, STR_NULL),
        NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_GO_BASE_SFX_TEXTFILE + TFT_LICENSE), SetFill(1, 0), SetResize(1, 0), SetDataTip(STR_TEXTFILE_VIEW_LICENCE, STR_NULL),
      EndContainer(),
    EndContainer(),
 
    NWidget(WWT_FRAME, COLOUR_GREY), SetDataTip(STR_GAME_OPTIONS_BASE_MUSIC, STR_NULL), SetPadding(0, 10, 0, 10),
      NWidget(NWID_HORIZONTAL), SetPIP(0, 30, 0),
        NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_GO_BASE_MUSIC_DROPDOWN), SetMinimalSize(150, 12), SetDataTip(STR_BLACK_RAW_STRING, STR_GAME_OPTIONS_BASE_MUSIC_TOOLTIP),
        NWidget(WWT_TEXT, COLOUR_GREY, WID_GO_BASE_MUSIC_STATUS), SetMinimalSize(150, 12), SetDataTip(STR_EMPTY, STR_NULL), SetFill(1, 0),
      EndContainer(),
      NWidget(WWT_TEXT, COLOUR_GREY, WID_GO_BASE_MUSIC_DESCRIPTION), SetMinimalSize(330, 0), SetDataTip(STR_EMPTY, STR_GAME_OPTIONS_BASE_MUSIC_DESCRIPTION_TOOLTIP), SetFill(1, 0), SetPadding(6, 0, 6, 0),
      NWidget(NWID_HORIZONTAL, NC_EQUALSIZE), SetPIP(7, 0, 7),
        NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_GO_BASE_MUSIC_TEXTFILE + TFT_README), SetFill(1, 0), SetResize(1, 0), SetDataTip(STR_TEXTFILE_VIEW_README, STR_NULL),
        NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_GO_BASE_MUSIC_TEXTFILE + TFT_CHANGELOG), SetFill(1, 0), SetResize(1, 0), SetDataTip(STR_TEXTFILE_VIEW_CHANGELOG, STR_NULL),
        NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_GO_BASE_MUSIC_TEXTFILE + TFT_LICENSE), SetFill(1, 0), SetResize(1, 0), SetDataTip(STR_TEXTFILE_VIEW_LICENCE, STR_NULL),
      EndContainer(),
    EndContainer(),
  EndContainer(),
};
 
static WindowDesc _game_options_desc(
  WDP_CENTER, "settings_game", 0, 0,
  WC_GAME_OPTIONS, WC_NONE,
  0,
  _nested_game_options_widgets, lengthof(_nested_game_options_widgets)
);
 
void ShowGameOptions()
{
  DeleteWindowByClass(WC_GAME_OPTIONS);
  new GameOptionsWindow(&_game_options_desc);
}
 
static int SETTING_HEIGHT = 11;    
static const int LEVEL_WIDTH = 15; 
 
enum SettingEntryFlags {
  SEF_LEFT_DEPRESSED  = 0x01, 
  SEF_RIGHT_DEPRESSED = 0x02, 
  SEF_BUTTONS_MASK = (SEF_LEFT_DEPRESSED | SEF_RIGHT_DEPRESSED), 
 
  SEF_LAST_FIELD = 0x04, 
  SEF_FILTERED   = 0x08, 
};
 
enum RestrictionMode {
  RM_BASIC,                            
  RM_ADVANCED,                         
  RM_ALL,                              
  RM_CHANGED_AGAINST_DEFAULT,          
  RM_CHANGED_AGAINST_NEW,              
  RM_END,                              
};
DECLARE_POSTFIX_INCREMENT(RestrictionMode)
 
 
struct SettingFilter {
  StringFilter string;     
  RestrictionMode min_cat; 
  bool type_hides;         
  RestrictionMode mode;    
  SettingType type;        
};
 
struct BaseSettingEntry {
  byte flags; 
  byte level; 
 
  BaseSettingEntry() : flags(0), level(0) {}
  virtual ~BaseSettingEntry() {}
 
  virtual void Init(byte level = 0);
  virtual void FoldAll() {}
  virtual void UnFoldAll() {}
 
  void SetLastField(bool last_field) { if (last_field) SETBITS(this->flags, SEF_LAST_FIELD); else CLRBITS(this->flags, SEF_LAST_FIELD); }
 
  virtual uint Length() const = 0;
  virtual void GetFoldingState(bool &all_folded, bool &all_unfolded) const {}
  virtual bool IsVisible(const BaseSettingEntry *item) const;
  virtual BaseSettingEntry *FindEntry(uint row, uint *cur_row);
  virtual uint GetMaxHelpHeight(int maxw) { return 0; }
 
  bool IsFiltered() const { return (this->flags & SEF_FILTERED) != 0; }
 
  virtual bool UpdateFilterState(SettingFilter &filter, bool force_visible) = 0;
 
  virtual uint Draw(GameSettings *settings_ptr, int left, int right, int y, uint first_row, uint max_row, BaseSettingEntry *selected, uint cur_row = 0, uint parent_last = 0) const;
 
protected:
  virtual void DrawSetting(GameSettings *settings_ptr, int left, int right, int y, bool highlight) const = 0;
};
 
struct SettingEntry : BaseSettingEntry {
  const char *name;           
  const SettingDesc *setting; 
  uint index;                 
 
  SettingEntry(const char *name);
 
  virtual void Init(byte level = 0);
  virtual uint Length() const;
  virtual uint GetMaxHelpHeight(int maxw);
  virtual bool UpdateFilterState(SettingFilter &filter, bool force_visible);
 
  void SetButtons(byte new_val);
 
  inline StringID GetHelpText() const
  {
    return this->setting->desc.str_help;
  }
 
  void SetValueDParams(uint first_param, int32 value) const;
 
protected:
  virtual void DrawSetting(GameSettings *settings_ptr, int left, int right, int y, bool highlight) const;
 
private:
  bool IsVisibleByRestrictionMode(RestrictionMode mode) const;
};
 
struct SettingsContainer {
  typedef std::vector<BaseSettingEntry*> EntryVector;
  EntryVector entries; 
 
  template<typename T>
  T *Add(T *item)
  {
    this->entries.push_back(item);
    return item;
  }
 
  void Init(byte level = 0);
  void FoldAll();
  void UnFoldAll();
 
  uint Length() const;
  void GetFoldingState(bool &all_folded, bool &all_unfolded) const;
  bool IsVisible(const BaseSettingEntry *item) const;
  BaseSettingEntry *FindEntry(uint row, uint *cur_row);
  uint GetMaxHelpHeight(int maxw);
 
  bool UpdateFilterState(SettingFilter &filter, bool force_visible);
 
  uint Draw(GameSettings *settings_ptr, int left, int right, int y, uint first_row, uint max_row, BaseSettingEntry *selected, uint cur_row = 0, uint parent_last = 0) const;
};
 
struct SettingsPage : BaseSettingEntry, SettingsContainer {
  StringID title;     
  bool folded;        
 
  SettingsPage(StringID title);
 
  virtual void Init(byte level = 0);
  virtual void FoldAll();
  virtual void UnFoldAll();
 
  virtual uint Length() const;
  virtual void GetFoldingState(bool &all_folded, bool &all_unfolded) const;
  virtual bool IsVisible(const BaseSettingEntry *item) const;
  virtual BaseSettingEntry *FindEntry(uint row, uint *cur_row);
  virtual uint GetMaxHelpHeight(int maxw) { return SettingsContainer::GetMaxHelpHeight(maxw); }
 
  virtual bool UpdateFilterState(SettingFilter &filter, bool force_visible);
 
  virtual uint Draw(GameSettings *settings_ptr, int left, int right, int y, uint first_row, uint max_row, BaseSettingEntry *selected, uint cur_row = 0, uint parent_last = 0) const;
 
protected:
  virtual void DrawSetting(GameSettings *settings_ptr, int left, int right, int y, bool highlight) const;
};
 
/* == BaseSettingEntry methods == */
 
void BaseSettingEntry::Init(byte level)
{
  this->level = level;
}
 
bool BaseSettingEntry::IsVisible(const BaseSettingEntry *item) const
{
  if (this->IsFiltered()) return false;
  if (this == item) return true;
  return false;
}
 
BaseSettingEntry *BaseSettingEntry::FindEntry(uint row_num, uint *cur_row)
{
  if (this->IsFiltered()) return nullptr;
  if (row_num == *cur_row) return this;
  (*cur_row)++;
  return nullptr;
}
 
uint BaseSettingEntry::Draw(GameSettings *settings_ptr, int left, int right, int y, uint first_row, uint max_row, BaseSettingEntry *selected, uint cur_row, uint parent_last) const
{
  if (this->IsFiltered()) return cur_row;
  if (cur_row >= max_row) return cur_row;
 
  bool rtl = _current_text_dir == TD_RTL;
  int offset = rtl ? -4 : 4;
  int level_width = rtl ? -LEVEL_WIDTH : LEVEL_WIDTH;
 
  int x = rtl ? right : left;
  if (cur_row >= first_row) {
    int colour = _colour_gradient[COLOUR_ORANGE][4];
    y += (cur_row - first_row) * SETTING_HEIGHT; // Compute correct y start position
 
    /* Draw vertical for parent nesting levels */
    for (uint lvl = 0; lvl < this->level; lvl++) {
      if (!HasBit(parent_last, lvl)) GfxDrawLine(x + offset, y, x + offset, y + SETTING_HEIGHT - 1, colour);
      x += level_width;
    }
    /* draw own |- prefix */
    int halfway_y = y + SETTING_HEIGHT / 2;
    int bottom_y = (flags & SEF_LAST_FIELD) ? halfway_y : y + SETTING_HEIGHT - 1;
    GfxDrawLine(x + offset, y, x + offset, bottom_y, colour);
    /* Small horizontal line from the last vertical line */
    GfxDrawLine(x + offset, halfway_y, x + level_width - offset, halfway_y, colour);
    x += level_width;
 
    this->DrawSetting(settings_ptr, rtl ? left : x, rtl ? x : right, y, this == selected);
  }
  cur_row++;
 
  return cur_row;
}
 
/* == SettingEntry methods == */
 
SettingEntry::SettingEntry(const char *name)
{
  this->name = name;
  this->setting = nullptr;
  this->index = 0;
}
 
void SettingEntry::Init(byte level)
{
  BaseSettingEntry::Init(level);
  this->setting = GetSettingFromName(this->name, &this->index);
  assert(this->setting != nullptr);
}
 
void SettingEntry::SetButtons(byte new_val)
{
  assert((new_val & ~SEF_BUTTONS_MASK) == 0); // Should not touch any flags outside the buttons
  this->flags = (this->flags & ~SEF_BUTTONS_MASK) | new_val;
}
 
uint SettingEntry::Length() const
{
  return this->IsFiltered() ? 0 : 1;
}
 
uint SettingEntry::GetMaxHelpHeight(int maxw)
{
  return GetStringHeight(this->GetHelpText(), maxw);
}
 
bool SettingEntry::IsVisibleByRestrictionMode(RestrictionMode mode) const
{
  /* There shall not be any restriction, i.e. all settings shall be visible. */
  if (mode == RM_ALL) return true;
 
  GameSettings *settings_ptr = &GetGameSettings();
  const SettingDesc *sd = this->setting;
 
  if (mode == RM_BASIC) return (this->setting->desc.cat & SC_BASIC_LIST) != 0;
  if (mode == RM_ADVANCED) return (this->setting->desc.cat & SC_ADVANCED_LIST) != 0;
 
  /* Read the current value. */
  const void *var = ResolveVariableAddress(settings_ptr, sd);
  int64 current_value = ReadValue(var, sd->save.conv);
 
  int64 filter_value;
 
  if (mode == RM_CHANGED_AGAINST_DEFAULT) {
    /* This entry shall only be visible, if the value deviates from its default value. */
 
    /* Read the default value. */
    filter_value = ReadValue(&sd->desc.def, sd->save.conv);
  } else {
    assert(mode == RM_CHANGED_AGAINST_NEW);
    /* This entry shall only be visible, if the value deviates from
     * its value is used when starting a new game. */
 
    /* Make sure we're not comparing the new game settings against itself. */
    assert(settings_ptr != &_settings_newgame);
 
    /* Read the new game's value. */
    var = ResolveVariableAddress(&_settings_newgame, sd);
    filter_value = ReadValue(var, sd->save.conv);
  }
 
  return current_value != filter_value;
}
 
bool SettingEntry::UpdateFilterState(SettingFilter &filter, bool force_visible)
{
  CLRBITS(this->flags, SEF_FILTERED);
 
  bool visible = true;
 
  const SettingDesc *sd = this->setting;
  if (!force_visible && !filter.string.IsEmpty()) {
    /* Process the search text filter for this item. */
    filter.string.ResetState();
 
    const SettingDescBase *sdb = &sd->desc;
 
    SetDParam(0, STR_EMPTY);
    filter.string.AddLine(sdb->str);
    filter.string.AddLine(this->GetHelpText());
 
    visible = filter.string.GetState();
  }
 
  if (visible) {
    if (filter.type != ST_ALL && sd->GetType() != filter.type) {
      filter.type_hides = true;
      visible = false;
    }
    if (!this->IsVisibleByRestrictionMode(filter.mode)) {
      while (filter.min_cat < RM_ALL && (filter.min_cat == filter.mode || !this->IsVisibleByRestrictionMode(filter.min_cat))) filter.min_cat++;
      visible = false;
    }
  }
 
  if (!visible) SETBITS(this->flags, SEF_FILTERED);
  return visible;
}
 
 
static const void *ResolveVariableAddress(const GameSettings *settings_ptr, const SettingDesc *sd)
{
  if ((sd->desc.flags & SGF_PER_COMPANY) != 0) {
    if (Company::IsValidID(_local_company) && _game_mode != GM_MENU) {
      return GetVariableAddress(&Company::Get(_local_company)->settings, &sd->save);
    } else {
      return GetVariableAddress(&_settings_client.company, &sd->save);
    }
  } else {
    return GetVariableAddress(settings_ptr, &sd->save);
  }
}
 
void SettingEntry::SetValueDParams(uint first_param, int32 value) const
{
  const SettingDescBase *sdb = &this->setting->desc;
  if (sdb->cmd == SDT_BOOLX) {
    SetDParam(first_param++, value != 0 ? STR_CONFIG_SETTING_ON : STR_CONFIG_SETTING_OFF);
  } else {
    if ((sdb->flags & SGF_MULTISTRING) != 0) {
      SetDParam(first_param++, sdb->str_val - sdb->min + value);
    } else if ((sdb->flags & SGF_DISPLAY_ABS) != 0) {
      SetDParam(first_param++, sdb->str_val + ((value >= 0) ? 1 : 0));
      value = abs(value);
    } else {
      SetDParam(first_param++, sdb->str_val + ((value == 0 && (sdb->flags & SGF_0ISDISABLED) != 0) ? 1 : 0));
    }
    SetDParam(first_param++, value);
  }
}
 
void SettingEntry::DrawSetting(GameSettings *settings_ptr, int left, int right, int y, bool highlight) const
{
  const SettingDesc *sd = this->setting;
  const SettingDescBase *sdb = &sd->desc;
  const void *var = ResolveVariableAddress(settings_ptr, sd);
  int state = this->flags & SEF_BUTTONS_MASK;
 
  bool rtl = _current_text_dir == TD_RTL;
  uint buttons_left = rtl ? right + 1 - SETTING_BUTTON_WIDTH : left;
  uint text_left  = left + (rtl ? 0 : SETTING_BUTTON_WIDTH + 5);
  uint text_right = right - (rtl ? SETTING_BUTTON_WIDTH + 5 : 0);
  uint button_y = y + (SETTING_HEIGHT - SETTING_BUTTON_HEIGHT) / 2;
 
  /* We do not allow changes of some items when we are a client in a networkgame */
  bool editable = sd->IsEditable();
 
  SetDParam(0, highlight ? STR_ORANGE_STRING1_WHITE : STR_ORANGE_STRING1_LTBLUE);
  int32 value = (int32)ReadValue(var, sd->save.conv);
  if (sdb->cmd == SDT_BOOLX) {
    /* Draw checkbox for boolean-value either on/off */
    DrawBoolButton(buttons_left, button_y, value != 0, editable);
  } else if ((sdb->flags & SGF_MULTISTRING) != 0) {
    /* Draw [v] button for settings of an enum-type */
    DrawDropDownButton(buttons_left, button_y, COLOUR_YELLOW, state != 0, editable);
  } else {
    /* Draw [<][>] boxes for settings of an integer-type */
    DrawArrowButtons(buttons_left, button_y, COLOUR_YELLOW, state,
        editable && value != (sdb->flags & SGF_0ISDISABLED ? 0 : sdb->min), editable && (uint32)value != sdb->max);
  }
  this->SetValueDParams(1, value);
  DrawString(text_left, text_right, y + (SETTING_HEIGHT - FONT_HEIGHT_NORMAL) / 2, sdb->str, highlight ? TC_WHITE : TC_LIGHT_BLUE);
}
 
/* == SettingsContainer methods == */
 
void SettingsContainer::Init(byte level)
{
  for (EntryVector::iterator it = this->entries.begin(); it != this->entries.end(); ++it) {
    (*it)->Init(level);
  }
}
 
void SettingsContainer::FoldAll()
{
  for (EntryVector::iterator it = this->entries.begin(); it != this->entries.end(); ++it) {
    (*it)->FoldAll();
  }
}
 
void SettingsContainer::UnFoldAll()
{
  for (EntryVector::iterator it = this->entries.begin(); it != this->entries.end(); ++it) {
    (*it)->UnFoldAll();
  }
}
 
void SettingsContainer::GetFoldingState(bool &all_folded, bool &all_unfolded) const
{
  for (EntryVector::const_iterator it = this->entries.begin(); it != this->entries.end(); ++it) {
    (*it)->GetFoldingState(all_folded, all_unfolded);
  }
}
 
bool SettingsContainer::UpdateFilterState(SettingFilter &filter, bool force_visible)
{
  bool visible = false;
  bool first_visible = true;
  for (EntryVector::reverse_iterator it = this->entries.rbegin(); it != this->entries.rend(); ++it) {
    visible |= (*it)->UpdateFilterState(filter, force_visible);
    (*it)->SetLastField(first_visible);
    if (visible && first_visible) first_visible = false;
  }
  return visible;
}
 
 
bool SettingsContainer::IsVisible(const BaseSettingEntry *item) const
{
  for (EntryVector::const_iterator it = this->entries.begin(); it != this->entries.end(); ++it) {
    if ((*it)->IsVisible(item)) return true;
  }
  return false;
}
 
uint SettingsContainer::Length() const
{
  uint length = 0;
  for (EntryVector::const_iterator it = this->entries.begin(); it != this->entries.end(); ++it) {
    length += (*it)->Length();
  }
  return length;
}
 
BaseSettingEntry *SettingsContainer::FindEntry(uint row_num, uint *cur_row)
{
  BaseSettingEntry *pe = nullptr;
  for (EntryVector::iterator it = this->entries.begin(); it != this->entries.end(); ++it) {
    pe = (*it)->FindEntry(row_num, cur_row);
    if (pe != nullptr) {
      break;
    }
  }
  return pe;
}
 
uint SettingsContainer::GetMaxHelpHeight(int maxw)
{
  uint biggest = 0;
  for (EntryVector::const_iterator it = this->entries.begin(); it != this->entries.end(); ++it) {
    biggest = std::max(biggest, (*it)->GetMaxHelpHeight(maxw));
  }
  return biggest;
}
 
 
uint SettingsContainer::Draw(GameSettings *settings_ptr, int left, int right, int y, uint first_row, uint max_row, BaseSettingEntry *selected, uint cur_row, uint parent_last) const
{
  for (EntryVector::const_iterator it = this->entries.begin(); it != this->entries.end(); ++it) {
    cur_row = (*it)->Draw(settings_ptr, left, right, y, first_row, max_row, selected, cur_row, parent_last);
    if (cur_row >= max_row) {
      break;
    }
  }
  return cur_row;
}
 
/* == SettingsPage methods == */
 
SettingsPage::SettingsPage(StringID title)
{
  this->title = title;
  this->folded = true;
}
 
void SettingsPage::Init(byte level)
{
  BaseSettingEntry::Init(level);
  SettingsContainer::Init(level + 1);
}
 
void SettingsPage::FoldAll()
{
  if (this->IsFiltered()) return;
  this->folded = true;
 
  SettingsContainer::FoldAll();
}
 
void SettingsPage::UnFoldAll()
{
  if (this->IsFiltered()) return;
  this->folded = false;
 
  SettingsContainer::UnFoldAll();
}
 
void SettingsPage::GetFoldingState(bool &all_folded, bool &all_unfolded) const
{
  if (this->IsFiltered()) return;
 
  if (this->folded) {
    all_unfolded = false;
  } else {
    all_folded = false;
  }
 
  SettingsContainer::GetFoldingState(all_folded, all_unfolded);
}
 
bool SettingsPage::UpdateFilterState(SettingFilter &filter, bool force_visible)
{
  if (!force_visible && !filter.string.IsEmpty()) {
    filter.string.ResetState();
    filter.string.AddLine(this->title);
    force_visible = filter.string.GetState();
  }
 
  bool visible = SettingsContainer::UpdateFilterState(filter, force_visible);
  if (visible) {
    CLRBITS(this->flags, SEF_FILTERED);
  } else {
    SETBITS(this->flags, SEF_FILTERED);
  }
  return visible;
}
 
bool SettingsPage::IsVisible(const BaseSettingEntry *item) const
{
  if (this->IsFiltered()) return false;
  if (this == item) return true;
  if (this->folded) return false;
 
  return SettingsContainer::IsVisible(item);
}
 
uint SettingsPage::Length() const
{
  if (this->IsFiltered()) return 0;
  if (this->folded) return 1; // Only displaying the title
 
  return 1 + SettingsContainer::Length();
}
 
BaseSettingEntry *SettingsPage::FindEntry(uint row_num, uint *cur_row)
{
  if (this->IsFiltered()) return nullptr;
  if (row_num == *cur_row) return this;
  (*cur_row)++;
  if (this->folded) return nullptr;
 
  return SettingsContainer::FindEntry(row_num, cur_row);
}
 
uint SettingsPage::Draw(GameSettings *settings_ptr, int left, int right, int y, uint first_row, uint max_row, BaseSettingEntry *selected, uint cur_row, uint parent_last) const
{
  if (this->IsFiltered()) return cur_row;
  if (cur_row >= max_row) return cur_row;
 
  cur_row = BaseSettingEntry::Draw(settings_ptr, left, right, y, first_row, max_row, selected, cur_row, parent_last);
 
  if (!this->folded) {
    if (this->flags & SEF_LAST_FIELD) {
      assert(this->level < 8 * sizeof(parent_last));
      SetBit(parent_last, this->level); // Add own last-field state
    }
 
    cur_row = SettingsContainer::Draw(settings_ptr, left, right, y, first_row, max_row, selected, cur_row, parent_last);
  }
 
  return cur_row;
}
 
void SettingsPage::DrawSetting(GameSettings *settings_ptr, int left, int right, int y, bool highlight) const
{
  bool rtl = _current_text_dir == TD_RTL;
  DrawSprite((this->folded ? SPR_CIRCLE_FOLDED : SPR_CIRCLE_UNFOLDED), PAL_NONE, rtl ? right - _circle_size.width : left, y + (SETTING_HEIGHT - _circle_size.height) / 2);
  DrawString(rtl ? left : left + _circle_size.width + 2, rtl ? right - _circle_size.width - 2 : right, y + (SETTING_HEIGHT - FONT_HEIGHT_NORMAL) / 2, this->title);
}
 
static SettingsContainer &GetSettingsTree()
{
  static SettingsContainer *main = nullptr;
 
  if (main == nullptr)
  {
    /* Build up the dynamic settings-array only once per OpenTTD session */
    main = new SettingsContainer();
 
    SettingsPage *localisation = main->Add(new SettingsPage(STR_CONFIG_SETTING_LOCALISATION));
    {
      localisation->Add(new SettingEntry("locale.units_velocity"));
      localisation->Add(new SettingEntry("locale.units_power"));
      localisation->Add(new SettingEntry("locale.units_weight"));
      localisation->Add(new SettingEntry("locale.units_volume"));
      localisation->Add(new SettingEntry("locale.units_force"));
      localisation->Add(new SettingEntry("locale.units_height"));
      localisation->Add(new SettingEntry("gui.date_format_in_default_names"));
    }
 
    SettingsPage *graphics = main->Add(new SettingsPage(STR_CONFIG_SETTING_GRAPHICS));
    {
      graphics->Add(new SettingEntry("gui.zoom_min"));
      graphics->Add(new SettingEntry("gui.zoom_max"));
      graphics->Add(new SettingEntry("gui.smallmap_land_colour"));
      graphics->Add(new SettingEntry("gui.graph_line_thickness"));
    }
 
    SettingsPage *sound = main->Add(new SettingsPage(STR_CONFIG_SETTING_SOUND));
    {
      sound->Add(new SettingEntry("sound.click_beep"));
      sound->Add(new SettingEntry("sound.confirm"));
      sound->Add(new SettingEntry("sound.news_ticker"));
      sound->Add(new SettingEntry("sound.news_full"));
      sound->Add(new SettingEntry("sound.new_year"));
      sound->Add(new SettingEntry("sound.disaster"));
      sound->Add(new SettingEntry("sound.vehicle"));
      sound->Add(new SettingEntry("sound.ambient"));
    }
 
    SettingsPage *interface = main->Add(new SettingsPage(STR_CONFIG_SETTING_INTERFACE));
    {
      SettingsPage *general = interface->Add(new SettingsPage(STR_CONFIG_SETTING_INTERFACE_GENERAL));
      {
        general->Add(new SettingEntry("gui.osk_activation"));
        general->Add(new SettingEntry("gui.hover_delay_ms"));
        general->Add(new SettingEntry("gui.errmsg_duration"));
        general->Add(new SettingEntry("gui.window_snap_radius"));
        general->Add(new SettingEntry("gui.window_soft_limit"));
        general->Add(new SettingEntry("gui.right_mouse_wnd_close"));
      }
 
      SettingsPage *viewports = interface->Add(new SettingsPage(STR_CONFIG_SETTING_INTERFACE_VIEWPORTS));
      {
        viewports->Add(new SettingEntry("gui.auto_scrolling"));
        viewports->Add(new SettingEntry("gui.scroll_mode"));
        viewports->Add(new SettingEntry("gui.smooth_scroll"));
        /* While the horizontal scrollwheel scrolling is written as general code, only
         *  the cocoa (OSX) driver generates input for it.
         *  Since it's also able to completely disable the scrollwheel will we display it on all platforms anyway */
        viewports->Add(new SettingEntry("gui.scrollwheel_scrolling"));
        viewports->Add(new SettingEntry("gui.scrollwheel_multiplier"));
#ifdef __APPLE__
        /* We might need to emulate a right mouse button on mac */
        viewports->Add(new SettingEntry("gui.right_mouse_btn_emulation"));
#endif
        viewports->Add(new SettingEntry("gui.population_in_label"));
        viewports->Add(new SettingEntry("gui.liveries"));
        viewports->Add(new SettingEntry("construction.train_signal_side"));
        viewports->Add(new SettingEntry("gui.measure_tooltip"));
        viewports->Add(new SettingEntry("gui.loading_indicators"));
        viewports->Add(new SettingEntry("gui.show_track_reservation"));
      }
 
      SettingsPage *construction = interface->Add(new SettingsPage(STR_CONFIG_SETTING_INTERFACE_CONSTRUCTION));
      {
        construction->Add(new SettingEntry("gui.link_terraform_toolbar"));
        construction->Add(new SettingEntry("gui.enable_signal_gui"));
        construction->Add(new SettingEntry("gui.persistent_buildingtools"));
        construction->Add(new SettingEntry("gui.quick_goto"));
        construction->Add(new SettingEntry("gui.default_rail_type"));
      }
 
      interface->Add(new SettingEntry("gui.autosave"));
      interface->Add(new SettingEntry("gui.toolbar_pos"));
      interface->Add(new SettingEntry("gui.statusbar_pos"));
      interface->Add(new SettingEntry("gui.prefer_teamchat"));
      interface->Add(new SettingEntry("gui.advanced_vehicle_list"));
      interface->Add(new SettingEntry("gui.timetable_in_ticks"));
      interface->Add(new SettingEntry("gui.timetable_arrival_departure"));
      interface->Add(new SettingEntry("gui.expenses_layout"));
      interface->Add(new SettingEntry("gui.show_newgrf_name"));
    }
 
    SettingsPage *advisors = main->Add(new SettingsPage(STR_CONFIG_SETTING_ADVISORS));
    {
      advisors->Add(new SettingEntry("gui.coloured_news_year"));
      advisors->Add(new SettingEntry("news_display.general"));
      advisors->Add(new SettingEntry("news_display.new_vehicles"));
      advisors->Add(new SettingEntry("news_display.accident"));
      advisors->Add(new SettingEntry("news_display.company_info"));
      advisors->Add(new SettingEntry("news_display.acceptance"));
      advisors->Add(new SettingEntry("news_display.arrival_player"));
      advisors->Add(new SettingEntry("news_display.arrival_other"));
      advisors->Add(new SettingEntry("news_display.advice"));
      advisors->Add(new SettingEntry("gui.order_review_system"));
      advisors->Add(new SettingEntry("gui.vehicle_income_warn"));
      advisors->Add(new SettingEntry("gui.lost_vehicle_warn"));
      advisors->Add(new SettingEntry("gui.show_finances"));
      advisors->Add(new SettingEntry("news_display.economy"));
      advisors->Add(new SettingEntry("news_display.subsidies"));
      advisors->Add(new SettingEntry("news_display.open"));
      advisors->Add(new SettingEntry("news_display.close"));
      advisors->Add(new SettingEntry("news_display.production_player"));
      advisors->Add(new SettingEntry("news_display.production_other"));
      advisors->Add(new SettingEntry("news_display.production_nobody"));
    }
 
    SettingsPage *company = main->Add(new SettingsPage(STR_CONFIG_SETTING_COMPANY));
    {
      company->Add(new SettingEntry("gui.semaphore_build_before"));
      company->Add(new SettingEntry("gui.default_signal_type"));
      company->Add(new SettingEntry("gui.cycle_signal_types"));
      company->Add(new SettingEntry("gui.drag_signals_fixed_distance"));
      company->Add(new SettingEntry("gui.auto_remove_signals"));
      company->Add(new SettingEntry("gui.new_nonstop"));
      company->Add(new SettingEntry("gui.stop_location"));
      company->Add(new SettingEntry("gui.starting_colour"));
      company->Add(new SettingEntry("company.engine_renew"));
      company->Add(new SettingEntry("company.engine_renew_months"));
      company->Add(new SettingEntry("company.engine_renew_money"));
      company->Add(new SettingEntry("vehicle.servint_ispercent"));
      company->Add(new SettingEntry("vehicle.servint_trains"));
      company->Add(new SettingEntry("vehicle.servint_roadveh"));
      company->Add(new SettingEntry("vehicle.servint_ships"));
      company->Add(new SettingEntry("vehicle.servint_aircraft"));
    }
 
    SettingsPage *accounting = main->Add(new SettingsPage(STR_CONFIG_SETTING_ACCOUNTING));
    {
      accounting->Add(new SettingEntry("economy.inflation"));
      accounting->Add(new SettingEntry("difficulty.initial_interest"));
      accounting->Add(new SettingEntry("difficulty.max_loan"));
      accounting->Add(new SettingEntry("difficulty.subsidy_multiplier"));
      accounting->Add(new SettingEntry("economy.feeder_payment_share"));
      accounting->Add(new SettingEntry("economy.infrastructure_maintenance"));
      accounting->Add(new SettingEntry("difficulty.vehicle_costs"));
      accounting->Add(new SettingEntry("difficulty.construction_cost"));
    }
 
    SettingsPage *vehicles = main->Add(new SettingsPage(STR_CONFIG_SETTING_VEHICLES));
    {
      SettingsPage *physics = vehicles->Add(new SettingsPage(STR_CONFIG_SETTING_VEHICLES_PHYSICS));
      {
        physics->Add(new SettingEntry("vehicle.train_acceleration_model"));
        physics->Add(new SettingEntry("vehicle.train_slope_steepness"));
        physics->Add(new SettingEntry("vehicle.wagon_speed_limits"));
        physics->Add(new SettingEntry("vehicle.freight_trains"));
        physics->Add(new SettingEntry("vehicle.roadveh_acceleration_model"));
        physics->Add(new SettingEntry("vehicle.roadveh_slope_steepness"));
        physics->Add(new SettingEntry("vehicle.smoke_amount"));
        physics->Add(new SettingEntry("vehicle.plane_speed"));
      }
 
      SettingsPage *routing = vehicles->Add(new SettingsPage(STR_CONFIG_SETTING_VEHICLES_ROUTING));
      {
        routing->Add(new SettingEntry("pf.pathfinder_for_trains"));
        routing->Add(new SettingEntry("difficulty.line_reverse_mode"));
        routing->Add(new SettingEntry("pf.reverse_at_signals"));
        routing->Add(new SettingEntry("pf.forbid_90_deg"));
        routing->Add(new SettingEntry("pf.pathfinder_for_roadvehs"));
        routing->Add(new SettingEntry("pf.pathfinder_for_ships"));
      }
 
      vehicles->Add(new SettingEntry("order.no_servicing_if_no_breakdowns"));
      vehicles->Add(new SettingEntry("order.serviceathelipad"));
    }
 
    SettingsPage *limitations = main->Add(new SettingsPage(STR_CONFIG_SETTING_LIMITATIONS));
    {
      limitations->Add(new SettingEntry("construction.command_pause_level"));
      limitations->Add(new SettingEntry("construction.autoslope"));
      limitations->Add(new SettingEntry("construction.extra_dynamite"));
      limitations->Add(new SettingEntry("construction.max_heightlevel"));
      limitations->Add(new SettingEntry("construction.max_bridge_length"));
      limitations->Add(new SettingEntry("construction.max_bridge_height"));
      limitations->Add(new SettingEntry("construction.max_tunnel_length"));
      limitations->Add(new SettingEntry("station.never_expire_airports"));
      limitations->Add(new SettingEntry("vehicle.never_expire_vehicles"));
      limitations->Add(new SettingEntry("vehicle.max_trains"));
      limitations->Add(new SettingEntry("vehicle.max_roadveh"));
      limitations->Add(new SettingEntry("vehicle.max_aircraft"));
      limitations->Add(new SettingEntry("vehicle.max_ships"));
      limitations->Add(new SettingEntry("vehicle.max_train_length"));
      limitations->Add(new SettingEntry("station.station_spread"));
      limitations->Add(new SettingEntry("station.distant_join_stations"));
      limitations->Add(new SettingEntry("construction.road_stop_on_town_road"));
      limitations->Add(new SettingEntry("construction.road_stop_on_competitor_road"));
      limitations->Add(new SettingEntry("vehicle.disable_elrails"));
    }
 
    SettingsPage *disasters = main->Add(new SettingsPage(STR_CONFIG_SETTING_ACCIDENTS));
    {
      disasters->Add(new SettingEntry("difficulty.disasters"));
      disasters->Add(new SettingEntry("difficulty.economy"));
      disasters->Add(new SettingEntry("difficulty.vehicle_breakdowns"));
      disasters->Add(new SettingEntry("vehicle.plane_crashes"));
    }
 
    SettingsPage *genworld = main->Add(new SettingsPage(STR_CONFIG_SETTING_GENWORLD));
    {
      genworld->Add(new SettingEntry("game_creation.landscape"));
      genworld->Add(new SettingEntry("game_creation.land_generator"));
      genworld->Add(new SettingEntry("difficulty.terrain_type"));
      genworld->Add(new SettingEntry("game_creation.tgen_smoothness"));
      genworld->Add(new SettingEntry("game_creation.variety"));
      genworld->Add(new SettingEntry("game_creation.snow_line_height"));
      genworld->Add(new SettingEntry("game_creation.amount_of_rivers"));
      genworld->Add(new SettingEntry("game_creation.tree_placer"));
      genworld->Add(new SettingEntry("vehicle.road_side"));
      genworld->Add(new SettingEntry("economy.larger_towns"));
      genworld->Add(new SettingEntry("economy.initial_city_size"));
      genworld->Add(new SettingEntry("economy.town_layout"));
      genworld->Add(new SettingEntry("difficulty.industry_density"));
      genworld->Add(new SettingEntry("gui.pause_on_newgame"));
      genworld->Add(new SettingEntry("game_creation.ending_year"));
    }
 
    SettingsPage *environment = main->Add(new SettingsPage(STR_CONFIG_SETTING_ENVIRONMENT));
    {
      SettingsPage *authorities = environment->Add(new SettingsPage(STR_CONFIG_SETTING_ENVIRONMENT_AUTHORITIES));
      {
        authorities->Add(new SettingEntry("difficulty.town_council_tolerance"));
        authorities->Add(new SettingEntry("economy.bribe"));
        authorities->Add(new SettingEntry("economy.exclusive_rights"));
        authorities->Add(new SettingEntry("economy.fund_roads"));
        authorities->Add(new SettingEntry("economy.fund_buildings"));
        authorities->Add(new SettingEntry("economy.station_noise_level"));
      }
 
      SettingsPage *towns = environment->Add(new SettingsPage(STR_CONFIG_SETTING_ENVIRONMENT_TOWNS));
      {
        towns->Add(new SettingEntry("economy.town_growth_rate"));
        towns->Add(new SettingEntry("economy.allow_town_roads"));
        towns->Add(new SettingEntry("economy.allow_town_level_crossings"));
        towns->Add(new SettingEntry("economy.found_town"));
        towns->Add(new SettingEntry("economy.town_cargogen_mode"));
      }
 
      SettingsPage *industries = environment->Add(new SettingsPage(STR_CONFIG_SETTING_ENVIRONMENT_INDUSTRIES));
      {
        industries->Add(new SettingEntry("construction.raw_industry_construction"));
        industries->Add(new SettingEntry("construction.industry_platform"));
        industries->Add(new SettingEntry("economy.multiple_industry_per_town"));
        industries->Add(new SettingEntry("game_creation.oil_refinery_limit"));
        industries->Add(new SettingEntry("economy.type"));
        industries->Add(new SettingEntry("station.serve_neutral_industries"));
      }
 
      SettingsPage *cdist = environment->Add(new SettingsPage(STR_CONFIG_SETTING_ENVIRONMENT_CARGODIST));
      {
        cdist->Add(new SettingEntry("linkgraph.recalc_time"));
        cdist->Add(new SettingEntry("linkgraph.recalc_interval"));
        cdist->Add(new SettingEntry("linkgraph.distribution_pax"));
        cdist->Add(new SettingEntry("linkgraph.distribution_mail"));
        cdist->Add(new SettingEntry("linkgraph.distribution_armoured"));
        cdist->Add(new SettingEntry("linkgraph.distribution_default"));
        cdist->Add(new SettingEntry("linkgraph.accuracy"));
        cdist->Add(new SettingEntry("linkgraph.demand_distance"));
        cdist->Add(new SettingEntry("linkgraph.demand_size"));
        cdist->Add(new SettingEntry("linkgraph.short_path_saturation"));
      }
 
      environment->Add(new SettingEntry("station.modified_catchment"));
      environment->Add(new SettingEntry("construction.extra_tree_placement"));
    }
 
    SettingsPage *ai = main->Add(new SettingsPage(STR_CONFIG_SETTING_AI));
    {
      SettingsPage *npc = ai->Add(new SettingsPage(STR_CONFIG_SETTING_AI_NPC));
      {
        npc->Add(new SettingEntry("script.settings_profile"));
        npc->Add(new SettingEntry("script.script_max_opcode_till_suspend"));
        npc->Add(new SettingEntry("script.script_max_memory_megabytes"));
        npc->Add(new SettingEntry("difficulty.competitor_speed"));
        npc->Add(new SettingEntry("ai.ai_in_multiplayer"));
        npc->Add(new SettingEntry("ai.ai_disable_veh_train"));
        npc->Add(new SettingEntry("ai.ai_disable_veh_roadveh"));
        npc->Add(new SettingEntry("ai.ai_disable_veh_aircraft"));
        npc->Add(new SettingEntry("ai.ai_disable_veh_ship"));
      }
 
      ai->Add(new SettingEntry("economy.give_money"));
      ai->Add(new SettingEntry("economy.allow_shares"));
      ai->Add(new SettingEntry("economy.min_years_for_shares"));
    }
 
    main->Init();
  }
  return *main;
}
 
static const StringID _game_settings_restrict_dropdown[] = {
  STR_CONFIG_SETTING_RESTRICT_BASIC,                            // RM_BASIC
  STR_CONFIG_SETTING_RESTRICT_ADVANCED,                         // RM_ADVANCED
  STR_CONFIG_SETTING_RESTRICT_ALL,                              // RM_ALL
  STR_CONFIG_SETTING_RESTRICT_CHANGED_AGAINST_DEFAULT,          // RM_CHANGED_AGAINST_DEFAULT
  STR_CONFIG_SETTING_RESTRICT_CHANGED_AGAINST_NEW,              // RM_CHANGED_AGAINST_NEW
};
static_assert(lengthof(_game_settings_restrict_dropdown) == RM_END);
 
enum WarnHiddenResult {
  WHR_NONE,          
  WHR_CATEGORY,      
  WHR_TYPE,          
  WHR_CATEGORY_TYPE, 
};
 
struct GameSettingsWindow : Window {
  static const int SETTINGTREE_LEFT_OFFSET   = 5; 
  static const int SETTINGTREE_RIGHT_OFFSET  = 5; 
  static const int SETTINGTREE_TOP_OFFSET    = 5; 
  static const int SETTINGTREE_BOTTOM_OFFSET = 5; 
 
  static GameSettings *settings_ptr; 
 
  SettingEntry *valuewindow_entry;   
  SettingEntry *clicked_entry;       
  SettingEntry *last_clicked;        
  SettingEntry *valuedropdown_entry; 
  bool closing_dropdown;             
 
  SettingFilter filter;              
  QueryString filter_editbox;        
  bool manually_changed_folding;     
  WarnHiddenResult warn_missing;     
  int warn_lines;                    
 
  Scrollbar *vscroll;
 
  GameSettingsWindow(WindowDesc *desc) : Window(desc), filter_editbox(50)
  {
    this->warn_missing = WHR_NONE;
    this->warn_lines = 0;
    this->filter.mode = (RestrictionMode)_settings_client.gui.settings_restriction_mode;
    this->filter.min_cat = RM_ALL;
    this->filter.type = ST_ALL;
    this->filter.type_hides = false;
    this->settings_ptr = &GetGameSettings();
 
    _circle_size = maxdim(GetSpriteSize(SPR_CIRCLE_FOLDED), GetSpriteSize(SPR_CIRCLE_UNFOLDED));
    GetSettingsTree().FoldAll(); // Close all sub-pages
 
    this->valuewindow_entry = nullptr; // No setting entry for which a entry window is opened
    this->clicked_entry = nullptr; // No numeric setting buttons are depressed
    this->last_clicked = nullptr;
    this->valuedropdown_entry = nullptr;
    this->closing_dropdown = false;
    this->manually_changed_folding = false;
 
    this->CreateNestedTree();
    this->vscroll = this->GetScrollbar(WID_GS_SCROLLBAR);
    this->FinishInitNested(WN_GAME_OPTIONS_GAME_SETTINGS);
 
    this->querystrings[WID_GS_FILTER] = &this->filter_editbox;
    this->filter_editbox.cancel_button = QueryString::ACTION_CLEAR;
    this->SetFocusedWidget(WID_GS_FILTER);
 
    this->InvalidateData();
  }
 
  void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize) override
  {
    switch (widget) {
      case WID_GS_OPTIONSPANEL:
        resize->height = SETTING_HEIGHT = std::max({(int)_circle_size.height, SETTING_BUTTON_HEIGHT, FONT_HEIGHT_NORMAL}) + 1;
        resize->width  = 1;
 
        size->height = 5 * resize->height + SETTINGTREE_TOP_OFFSET + SETTINGTREE_BOTTOM_OFFSET;
        break;
 
      case WID_GS_HELP_TEXT: {
        static const StringID setting_types[] = {
          STR_CONFIG_SETTING_TYPE_CLIENT,
          STR_CONFIG_SETTING_TYPE_COMPANY_MENU, STR_CONFIG_SETTING_TYPE_COMPANY_INGAME,
          STR_CONFIG_SETTING_TYPE_GAME_MENU, STR_CONFIG_SETTING_TYPE_GAME_INGAME,
        };
        for (uint i = 0; i < lengthof(setting_types); i++) {
          SetDParam(0, setting_types[i]);
          size->width = std::max(size->width, GetStringBoundingBox(STR_CONFIG_SETTING_TYPE).width);
        }
        size->height = 2 * FONT_HEIGHT_NORMAL + WD_PAR_VSEP_NORMAL +
            std::max(size->height, GetSettingsTree().GetMaxHelpHeight(size->width));
        break;
      }
 
      case WID_GS_RESTRICT_CATEGORY:
      case WID_GS_RESTRICT_TYPE:
        size->width = std::max(GetStringBoundingBox(STR_CONFIG_SETTING_RESTRICT_CATEGORY).width, GetStringBoundingBox(STR_CONFIG_SETTING_RESTRICT_TYPE).width);
        break;
 
      default:
        break;
    }
  }
 
  void OnPaint() override
  {
    if (this->closing_dropdown) {
      this->closing_dropdown = false;
      assert(this->valuedropdown_entry != nullptr);
      this->valuedropdown_entry->SetButtons(0);
      this->valuedropdown_entry = nullptr;
    }
 
    /* Reserve the correct number of lines for the 'some search results are hidden' notice in the central settings display panel. */
    const NWidgetBase *panel = this->GetWidget<NWidgetBase>(WID_GS_OPTIONSPANEL);
    StringID warn_str = STR_CONFIG_SETTING_CATEGORY_HIDES - 1 + this->warn_missing;
    int new_warn_lines;
    if (this->warn_missing == WHR_NONE) {
      new_warn_lines = 0;
    } else {
      SetDParam(0, _game_settings_restrict_dropdown[this->filter.min_cat]);
      new_warn_lines = GetStringLineCount(warn_str, panel->current_x);
    }
    if (this->warn_lines != new_warn_lines) {
      this->vscroll->SetCount(this->vscroll->GetCount() - this->warn_lines + new_warn_lines);
      this->warn_lines = new_warn_lines;
    }
 
    this->DrawWidgets();
 
    /* Draw the 'some search results are hidden' notice. */
    if (this->warn_missing != WHR_NONE) {
      const int left = panel->pos_x;
      const int right = left + panel->current_x - 1;
      const int top = panel->pos_y + WD_FRAMETEXT_TOP + (SETTING_HEIGHT - FONT_HEIGHT_NORMAL) * this->warn_lines / 2;
      SetDParam(0, _game_settings_restrict_dropdown[this->filter.min_cat]);
      if (this->warn_lines == 1) {
        /* If the warning fits at one line, center it. */
        DrawString(left + WD_FRAMETEXT_LEFT, right - WD_FRAMETEXT_RIGHT, top, warn_str, TC_FROMSTRING, SA_HOR_CENTER);
      } else {
        DrawStringMultiLine(left + WD_FRAMERECT_LEFT, right - WD_FRAMERECT_RIGHT, top, INT32_MAX, warn_str, TC_FROMSTRING, SA_HOR_CENTER);
      }
    }
  }
 
  void SetStringParameters(int widget) const override
  {
    switch (widget) {
      case WID_GS_RESTRICT_DROPDOWN:
        SetDParam(0, _game_settings_restrict_dropdown[this->filter.mode]);
        break;
 
      case WID_GS_TYPE_DROPDOWN:
        switch (this->filter.type) {
          case ST_GAME:    SetDParam(0, _game_mode == GM_MENU ? STR_CONFIG_SETTING_TYPE_DROPDOWN_GAME_MENU : STR_CONFIG_SETTING_TYPE_DROPDOWN_GAME_INGAME); break;
          case ST_COMPANY: SetDParam(0, _game_mode == GM_MENU ? STR_CONFIG_SETTING_TYPE_DROPDOWN_COMPANY_MENU : STR_CONFIG_SETTING_TYPE_DROPDOWN_COMPANY_INGAME); break;
          case ST_CLIENT:  SetDParam(0, STR_CONFIG_SETTING_TYPE_DROPDOWN_CLIENT); break;
          default:         SetDParam(0, STR_CONFIG_SETTING_TYPE_DROPDOWN_ALL); break;
        }
        break;
    }
  }
 
  DropDownList BuildDropDownList(int widget) const
  {
    DropDownList list;
    switch (widget) {
      case WID_GS_RESTRICT_DROPDOWN:
        for (int mode = 0; mode != RM_END; mode++) {
          /* If we are in adv. settings screen for the new game's settings,
           * we don't want to allow comparing with new game's settings. */
          bool disabled = mode == RM_CHANGED_AGAINST_NEW && settings_ptr == &_settings_newgame;
 
          list.emplace_back(new DropDownListStringItem(_game_settings_restrict_dropdown[mode], mode, disabled));
        }
        break;
 
      case WID_GS_TYPE_DROPDOWN:
        list.emplace_back(new DropDownListStringItem(STR_CONFIG_SETTING_TYPE_DROPDOWN_ALL, ST_ALL, false));
        list.emplace_back(new DropDownListStringItem(_game_mode == GM_MENU ? STR_CONFIG_SETTING_TYPE_DROPDOWN_GAME_MENU : STR_CONFIG_SETTING_TYPE_DROPDOWN_GAME_INGAME, ST_GAME, false));
        list.emplace_back(new DropDownListStringItem(_game_mode == GM_MENU ? STR_CONFIG_SETTING_TYPE_DROPDOWN_COMPANY_MENU : STR_CONFIG_SETTING_TYPE_DROPDOWN_COMPANY_INGAME, ST_COMPANY, false));
        list.emplace_back(new DropDownListStringItem(STR_CONFIG_SETTING_TYPE_DROPDOWN_CLIENT, ST_CLIENT, false));
        break;
    }
    return list;
  }
 
  void DrawWidget(const Rect &r, int widget) const override
  {
    switch (widget) {
      case WID_GS_OPTIONSPANEL: {
        int top_pos = r.top + SETTINGTREE_TOP_OFFSET + 1 + this->warn_lines * SETTING_HEIGHT;
        uint last_row = this->vscroll->GetPosition() + this->vscroll->GetCapacity() - this->warn_lines;
        int next_row = GetSettingsTree().Draw(settings_ptr, r.left + SETTINGTREE_LEFT_OFFSET, r.right - SETTINGTREE_RIGHT_OFFSET, top_pos,
            this->vscroll->GetPosition(), last_row, this->last_clicked);
        if (next_row == 0) DrawString(r.left + SETTINGTREE_LEFT_OFFSET, r.right - SETTINGTREE_RIGHT_OFFSET, top_pos, STR_CONFIG_SETTINGS_NONE);
        break;
      }
 
      case WID_GS_HELP_TEXT:
        if (this->last_clicked != nullptr) {
          const SettingDesc *sd = this->last_clicked->setting;
 
          int y = r.top;
          switch (sd->GetType()) {
            case ST_COMPANY: SetDParam(0, _game_mode == GM_MENU ? STR_CONFIG_SETTING_TYPE_COMPANY_MENU : STR_CONFIG_SETTING_TYPE_COMPANY_INGAME); break;
            case ST_CLIENT:  SetDParam(0, STR_CONFIG_SETTING_TYPE_CLIENT); break;
            case ST_GAME:    SetDParam(0, _game_mode == GM_MENU ? STR_CONFIG_SETTING_TYPE_GAME_MENU : STR_CONFIG_SETTING_TYPE_GAME_INGAME); break;
            default: NOT_REACHED();
          }
          DrawString(r.left, r.right, y, STR_CONFIG_SETTING_TYPE);
          y += FONT_HEIGHT_NORMAL;
 
          int32 default_value = ReadValue(&sd->desc.def, sd->save.conv);
          this->last_clicked->SetValueDParams(0, default_value);
          DrawString(r.left, r.right, y, STR_CONFIG_SETTING_DEFAULT_VALUE);
          y += FONT_HEIGHT_NORMAL + WD_PAR_VSEP_NORMAL;
 
          DrawStringMultiLine(r.left, r.right, y, r.bottom, this->last_clicked->GetHelpText(), TC_WHITE);
        }
        break;
 
      default:
        break;
    }
  }
 
  void SetDisplayedHelpText(SettingEntry *pe)
  {
    if (this->last_clicked != pe) this->SetDirty();
    this->last_clicked = pe;
  }
 
  void OnClick(Point pt, int widget, int click_count) override
  {
    switch (widget) {
      case WID_GS_EXPAND_ALL:
        this->manually_changed_folding = true;
        GetSettingsTree().UnFoldAll();
        this->InvalidateData();
        break;
 
      case WID_GS_COLLAPSE_ALL:
        this->manually_changed_folding = true;
        GetSettingsTree().FoldAll();
        this->InvalidateData();
        break;
 
      case WID_GS_RESTRICT_DROPDOWN: {
        DropDownList list = this->BuildDropDownList(widget);
        if (!list.empty()) {
          ShowDropDownList(this, std::move(list), this->filter.mode, widget);
        }
        break;
      }
 
      case WID_GS_TYPE_DROPDOWN: {
        DropDownList list = this->BuildDropDownList(widget);
        if (!list.empty()) {
          ShowDropDownList(this, std::move(list), this->filter.type, widget);
        }
        break;
      }
    }
 
    if (widget != WID_GS_OPTIONSPANEL) return;
 
    uint btn = this->vscroll->GetScrolledRowFromWidget(pt.y, this, WID_GS_OPTIONSPANEL, SETTINGTREE_TOP_OFFSET);
    if (btn == INT_MAX || (int)btn < this->warn_lines) return;
    btn -= this->warn_lines;
 
    uint cur_row = 0;
    BaseSettingEntry *clicked_entry = GetSettingsTree().FindEntry(btn, &cur_row);
 
    if (clicked_entry == nullptr) return;  // Clicked below the last setting of the page
 
    int x = (_current_text_dir == TD_RTL ? this->width - 1 - pt.x : pt.x) - SETTINGTREE_LEFT_OFFSET - (clicked_entry->level + 1) * LEVEL_WIDTH;  // Shift x coordinate
    if (x < 0) return;  // Clicked left of the entry
 
    SettingsPage *clicked_page = dynamic_cast<SettingsPage*>(clicked_entry);
    if (clicked_page != nullptr) {
      this->SetDisplayedHelpText(nullptr);
      clicked_page->folded = !clicked_page->folded; // Flip 'folded'-ness of the sub-page
 
      this->manually_changed_folding = true;
 
      this->InvalidateData();
      return;
    }
 
    SettingEntry *pe = dynamic_cast<SettingEntry*>(clicked_entry);
    assert(pe != nullptr);
    const SettingDesc *sd = pe->setting;
 
    /* return if action is only active in network, or only settable by server */
    if (!sd->IsEditable()) {
      this->SetDisplayedHelpText(pe);
      return;
    }
 
    const void *var = ResolveVariableAddress(settings_ptr, sd);
    int32 value = (int32)ReadValue(var, sd->save.conv);
 
    /* clicked on the icon on the left side. Either scroller, bool on/off or dropdown */
    if (x < SETTING_BUTTON_WIDTH && (sd->desc.flags & SGF_MULTISTRING)) {
      const SettingDescBase *sdb = &sd->desc;
      this->SetDisplayedHelpText(pe);
 
      if (this->valuedropdown_entry == pe) {
        /* unclick the dropdown */
        HideDropDownMenu(this);
        this->closing_dropdown = false;
        this->valuedropdown_entry->SetButtons(0);
        this->valuedropdown_entry = nullptr;
      } else {
        if (this->valuedropdown_entry != nullptr) this->valuedropdown_entry->SetButtons(0);
        this->closing_dropdown = false;
 
        const NWidgetBase *wid = this->GetWidget<NWidgetBase>(WID_GS_OPTIONSPANEL);
        int rel_y = (pt.y - (int)wid->pos_y - SETTINGTREE_TOP_OFFSET) % wid->resize_y;
 
        Rect wi_rect;
        wi_rect.left = pt.x - (_current_text_dir == TD_RTL ? SETTING_BUTTON_WIDTH - 1 - x : x);
        wi_rect.right = wi_rect.left + SETTING_BUTTON_WIDTH - 1;
        wi_rect.top = pt.y - rel_y + (SETTING_HEIGHT - SETTING_BUTTON_HEIGHT) / 2;
        wi_rect.bottom = wi_rect.top + SETTING_BUTTON_HEIGHT - 1;
 
        /* For dropdowns we also have to check the y position thoroughly, the mouse may not above the just opening dropdown */
        if (pt.y >= wi_rect.top && pt.y <= wi_rect.bottom) {
          this->valuedropdown_entry = pe;
          this->valuedropdown_entry->SetButtons(SEF_LEFT_DEPRESSED);
 
          DropDownList list;
          for (int i = sdb->min; i <= (int)sdb->max; i++) {
            list.emplace_back(new DropDownListStringItem(sdb->str_val + i - sdb->min, i, false));
          }
 
          ShowDropDownListAt(this, std::move(list), value, -1, wi_rect, COLOUR_ORANGE, true);
        }
      }
      this->SetDirty();
    } else if (x < SETTING_BUTTON_WIDTH) {
      this->SetDisplayedHelpText(pe);
      const SettingDescBase *sdb = &sd->desc;
      int32 oldvalue = value;
 
      switch (sdb->cmd) {
        case SDT_BOOLX: value ^= 1; break;
        case SDT_ONEOFMANY:
        case SDT_NUMX: {
          /* Add a dynamic step-size to the scroller. In a maximum of
           * 50-steps you should be able to get from min to max,
           * unless specified otherwise in the 'interval' variable
           * of the current setting. */
          uint32 step = (sdb->interval == 0) ? ((sdb->max - sdb->min) / 50) : sdb->interval;
          if (step == 0) step = 1;
 
          /* don't allow too fast scrolling */
          if ((this->flags & WF_TIMEOUT) && this->timeout_timer > 1) {
            _left_button_clicked = false;
            return;
          }
 
          /* Increase or decrease the value and clamp it to extremes */
          if (x >= SETTING_BUTTON_WIDTH / 2) {
            value += step;
            if (sdb->min < 0) {
              assert((int32)sdb->max >= 0);
              if (value > (int32)sdb->max) value = (int32)sdb->max;
            } else {
              if ((uint32)value > sdb->max) value = (int32)sdb->max;
            }
            if (value < sdb->min) value = sdb->min; // skip between "disabled" and minimum
          } else {
            value -= step;
            if (value < sdb->min) value = (sdb->flags & SGF_0ISDISABLED) ? 0 : sdb->min;
          }
 
          /* Set up scroller timeout for numeric values */
          if (value != oldvalue) {
            if (this->clicked_entry != nullptr) { // Release previous buttons if any
              this->clicked_entry->SetButtons(0);
            }
            this->clicked_entry = pe;
            this->clicked_entry->SetButtons((x >= SETTING_BUTTON_WIDTH / 2) != (_current_text_dir == TD_RTL) ? SEF_RIGHT_DEPRESSED : SEF_LEFT_DEPRESSED);
            this->SetTimeout();
            _left_button_clicked = false;
          }
          break;
        }
 
        default: NOT_REACHED();
      }
 
      if (value != oldvalue) {
        if ((sd->desc.flags & SGF_PER_COMPANY) != 0) {
          SetCompanySetting(pe->index, value);
        } else {
          SetSettingValue(pe->index, value);
        }
        this->SetDirty();
      }
    } else {
      /* Only open editbox if clicked for the second time, and only for types where it is sensible for. */
      if (this->last_clicked == pe && sd->desc.cmd != SDT_BOOLX && !(sd->desc.flags & SGF_MULTISTRING)) {
        int64 value64 = value;
        /* Show the correct currency-translated value */
        if (sd->desc.flags & SGF_CURRENCY) value64 *= _currency->rate;
 
        this->valuewindow_entry = pe;
        SetDParam(0, value64);
        /* Limit string length to 14 so that MAX_INT32 * max currency rate doesn't exceed MAX_INT64. */
        ShowQueryString(STR_JUST_INT, STR_CONFIG_SETTING_QUERY_CAPTION, 15, this, CS_NUMERAL, QSF_ENABLE_DEFAULT);
      }
      this->SetDisplayedHelpText(pe);
    }
  }
 
  void OnTimeout() override
  {
    if (this->clicked_entry != nullptr) { // On timeout, release any depressed buttons
      this->clicked_entry->SetButtons(0);
      this->clicked_entry = nullptr;
      this->SetDirty();
    }
  }
 
  void OnQueryTextFinished(char *str) override
  {
    /* The user pressed cancel */
    if (str == nullptr) return;
 
    assert(this->valuewindow_entry != nullptr);
    const SettingDesc *sd = this->valuewindow_entry->setting;
 
    int32 value;
    if (!StrEmpty(str)) {
      long long llvalue = atoll(str);
 
      /* Save the correct currency-translated value */
      if (sd->desc.flags & SGF_CURRENCY) llvalue /= _currency->rate;
 
      value = (int32)ClampToI32(llvalue);
    } else {
      value = (int32)(size_t)sd->desc.def;
    }
 
    if ((sd->desc.flags & SGF_PER_COMPANY) != 0) {
      SetCompanySetting(this->valuewindow_entry->index, value);
    } else {
      SetSettingValue(this->valuewindow_entry->index, value);
    }
    this->SetDirty();
  }
 
  void OnDropdownSelect(int widget, int index) override
  {
    switch (widget) {
      case WID_GS_RESTRICT_DROPDOWN:
        this->filter.mode = (RestrictionMode)index;
        if (this->filter.mode == RM_CHANGED_AGAINST_DEFAULT ||
            this->filter.mode == RM_CHANGED_AGAINST_NEW) {
 
          if (!this->manually_changed_folding) {
            /* Expand all when selecting 'changes'. Update the filter state first, in case it becomes less restrictive in some cases. */
            GetSettingsTree().UpdateFilterState(this->filter, false);
            GetSettingsTree().UnFoldAll();
          }
        } else {
          /* Non-'changes' filter. Save as default. */
          _settings_client.gui.settings_restriction_mode = this->filter.mode;
        }
        this->InvalidateData();
        break;
 
      case WID_GS_TYPE_DROPDOWN:
        this->filter.type = (SettingType)index;
        this->InvalidateData();
        break;
 
      default:
        if (widget < 0) {
          /* Deal with drop down boxes on the panel. */
          assert(this->valuedropdown_entry != nullptr);
          const SettingDesc *sd = this->valuedropdown_entry->setting;
          assert(sd->desc.flags & SGF_MULTISTRING);
 
          if ((sd->desc.flags & SGF_PER_COMPANY) != 0) {
            SetCompanySetting(this->valuedropdown_entry->index, index);
          } else {
            SetSettingValue(this->valuedropdown_entry->index, index);
          }
 
          this->SetDirty();
        }
        break;
    }
  }
 
  void OnDropdownClose(Point pt, int widget, int index, bool instant_close) override
  {
    if (widget >= 0) {
      /* Normally the default implementation of OnDropdownClose() takes care of
       * a few things. We want that behaviour here too, but only for
       * "normal" dropdown boxes. The special dropdown boxes added for every
       * setting that needs one can't have this call. */
      Window::OnDropdownClose(pt, widget, index, instant_close);
    } else {
      /* We cannot raise the dropdown button just yet. OnClick needs some hint, whether
       * the same dropdown button was clicked again, and then not open the dropdown again.
       * So, we only remember that it was closed, and process it on the next OnPaint, which is
       * after OnClick. */
      assert(this->valuedropdown_entry != nullptr);
      this->closing_dropdown = true;
      this->SetDirty();
    }
  }
 
  void OnInvalidateData(int data = 0, bool gui_scope = true) override
  {
    if (!gui_scope) return;
 
    /* Update which settings are to be visible. */
    RestrictionMode min_level = (this->filter.mode <= RM_ALL) ? this->filter.mode : RM_BASIC;
    this->filter.min_cat = min_level;
    this->filter.type_hides = false;
    GetSettingsTree().UpdateFilterState(this->filter, false);
 
    if (this->filter.string.IsEmpty()) {
      this->warn_missing = WHR_NONE;
    } else if (min_level < this->filter.min_cat) {
      this->warn_missing = this->filter.type_hides ? WHR_CATEGORY_TYPE : WHR_CATEGORY;
    } else {
      this->warn_missing = this->filter.type_hides ? WHR_TYPE : WHR_NONE;
    }
    this->vscroll->SetCount(GetSettingsTree().Length() + this->warn_lines);
 
    if (this->last_clicked != nullptr && !GetSettingsTree().IsVisible(this->last_clicked)) {
      this->SetDisplayedHelpText(nullptr);
    }
 
    bool all_folded = true;
    bool all_unfolded = true;
    GetSettingsTree().GetFoldingState(all_folded, all_unfolded);
    this->SetWidgetDisabledState(WID_GS_EXPAND_ALL, all_unfolded);
    this->SetWidgetDisabledState(WID_GS_COLLAPSE_ALL, all_folded);
  }
 
  void OnEditboxChanged(int wid) override
  {
    if (wid == WID_GS_FILTER) {
      this->filter.string.SetFilterTerm(this->filter_editbox.text.buf);
      if (!this->filter.string.IsEmpty() && !this->manually_changed_folding) {
        /* User never expanded/collapsed single pages and entered a filter term.
         * Expand everything, to save weird expand clicks, */
        GetSettingsTree().UnFoldAll();
      }
      this->InvalidateData();
    }
  }
 
  void OnResize() override
  {
    this->vscroll->SetCapacityFromWidget(this, WID_GS_OPTIONSPANEL, SETTINGTREE_TOP_OFFSET + SETTINGTREE_BOTTOM_OFFSET);
  }
};
 
GameSettings *GameSettingsWindow::settings_ptr = nullptr;
 
static const NWidgetPart _nested_settings_selection_widgets[] = {
  NWidget(NWID_HORIZONTAL),
    NWidget(WWT_CLOSEBOX, COLOUR_MAUVE),
    NWidget(WWT_CAPTION, COLOUR_MAUVE), SetDataTip(STR_CONFIG_SETTING_TREE_CAPTION, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
    NWidget(WWT_DEFSIZEBOX, COLOUR_MAUVE),
  EndContainer(),
  NWidget(WWT_PANEL, COLOUR_MAUVE),
    NWidget(NWID_VERTICAL), SetPIP(0, WD_PAR_VSEP_NORMAL, 0), SetPadding(WD_TEXTPANEL_TOP, 0, WD_TEXTPANEL_BOTTOM, 0),
      NWidget(NWID_HORIZONTAL), SetPIP(WD_FRAMETEXT_LEFT, WD_FRAMETEXT_RIGHT, WD_FRAMETEXT_RIGHT),
        NWidget(WWT_TEXT, COLOUR_MAUVE, WID_GS_RESTRICT_CATEGORY), SetDataTip(STR_CONFIG_SETTING_RESTRICT_CATEGORY, STR_NULL),
        NWidget(WWT_DROPDOWN, COLOUR_MAUVE, WID_GS_RESTRICT_DROPDOWN), SetMinimalSize(100, 12), SetDataTip(STR_BLACK_STRING, STR_CONFIG_SETTING_RESTRICT_DROPDOWN_HELPTEXT), SetFill(1, 0), SetResize(1, 0),
      EndContainer(),
      NWidget(NWID_HORIZONTAL), SetPIP(WD_FRAMETEXT_LEFT, WD_FRAMETEXT_RIGHT, WD_FRAMETEXT_RIGHT),
        NWidget(WWT_TEXT, COLOUR_MAUVE, WID_GS_RESTRICT_TYPE), SetDataTip(STR_CONFIG_SETTING_RESTRICT_TYPE, STR_NULL),
        NWidget(WWT_DROPDOWN, COLOUR_MAUVE, WID_GS_TYPE_DROPDOWN), SetMinimalSize(100, 12), SetDataTip(STR_BLACK_STRING, STR_CONFIG_SETTING_TYPE_DROPDOWN_HELPTEXT), SetFill(1, 0), SetResize(1, 0),
      EndContainer(),
    EndContainer(),
    NWidget(NWID_HORIZONTAL), SetPadding(0, 0, WD_TEXTPANEL_BOTTOM, 0),
        SetPIP(WD_FRAMETEXT_LEFT, WD_FRAMETEXT_RIGHT, WD_FRAMETEXT_RIGHT),
      NWidget(WWT_TEXT, COLOUR_MAUVE), SetFill(0, 1), SetDataTip(STR_CONFIG_SETTING_FILTER_TITLE, STR_NULL),
      NWidget(WWT_EDITBOX, COLOUR_MAUVE, WID_GS_FILTER), SetFill(1, 0), SetMinimalSize(50, 12), SetResize(1, 0),
          SetDataTip(STR_LIST_FILTER_OSKTITLE, STR_LIST_FILTER_TOOLTIP),
    EndContainer(),
  EndContainer(),
  NWidget(NWID_HORIZONTAL),
    NWidget(WWT_PANEL, COLOUR_MAUVE, WID_GS_OPTIONSPANEL), SetMinimalSize(400, 174), SetScrollbar(WID_GS_SCROLLBAR), EndContainer(),
    NWidget(NWID_VSCROLLBAR, COLOUR_MAUVE, WID_GS_SCROLLBAR),
  EndContainer(),
  NWidget(WWT_PANEL, COLOUR_MAUVE), SetMinimalSize(400, 40),
    NWidget(WWT_EMPTY, INVALID_COLOUR, WID_GS_HELP_TEXT), SetMinimalSize(300, 25), SetFill(1, 1), SetResize(1, 0),
        SetPadding(WD_FRAMETEXT_TOP, WD_FRAMETEXT_RIGHT, WD_FRAMETEXT_BOTTOM, WD_FRAMETEXT_LEFT),
  EndContainer(),
  NWidget(NWID_HORIZONTAL),
    NWidget(WWT_PUSHTXTBTN, COLOUR_MAUVE, WID_GS_EXPAND_ALL), SetDataTip(STR_CONFIG_SETTING_EXPAND_ALL, STR_NULL),
    NWidget(WWT_PUSHTXTBTN, COLOUR_MAUVE, WID_GS_COLLAPSE_ALL), SetDataTip(STR_CONFIG_SETTING_COLLAPSE_ALL, STR_NULL),
    NWidget(WWT_PANEL, COLOUR_MAUVE), SetFill(1, 0), SetResize(1, 0),
    EndContainer(),
    NWidget(WWT_RESIZEBOX, COLOUR_MAUVE),
  EndContainer(),
};
 
static WindowDesc _settings_selection_desc(
  WDP_CENTER, "settings", 510, 450,
  WC_GAME_OPTIONS, WC_NONE,
  0,
  _nested_settings_selection_widgets, lengthof(_nested_settings_selection_widgets)
);
 
void ShowGameSettings()
{
  DeleteWindowByClass(WC_GAME_OPTIONS);
  new GameSettingsWindow(&_settings_selection_desc);
}
 
 
void DrawArrowButtons(int x, int y, Colours button_colour, byte state, bool clickable_left, bool clickable_right)
{
  int colour = _colour_gradient[button_colour][2];
  Dimension dim = NWidgetScrollbar::GetHorizontalDimension();
 
  DrawFrameRect(x,             y, x + dim.width - 1,             y + dim.height - 1, button_colour, (state == 1) ? FR_LOWERED : FR_NONE);
  DrawFrameRect(x + dim.width, y, x + dim.width + dim.width - 1, y + dim.height - 1, button_colour, (state == 2) ? FR_LOWERED : FR_NONE);
  DrawSprite(SPR_ARROW_LEFT, PAL_NONE, x + WD_IMGBTN_LEFT, y + WD_IMGBTN_TOP);
  DrawSprite(SPR_ARROW_RIGHT, PAL_NONE, x + WD_IMGBTN_LEFT + dim.width, y + WD_IMGBTN_TOP);
 
  /* Grey out the buttons that aren't clickable */
  bool rtl = _current_text_dir == TD_RTL;
  if (rtl ? !clickable_right : !clickable_left) {
    GfxFillRect(x + 1, y, x + dim.width - 1, y + dim.height - 2, colour, FILLRECT_CHECKER);
  }
  if (rtl ? !clickable_left : !clickable_right) {
    GfxFillRect(x + dim.width + 1, y, x + dim.width + dim.width - 1, y + dim.height - 2, colour, FILLRECT_CHECKER);
  }
}
 
void DrawDropDownButton(int x, int y, Colours button_colour, bool state, bool clickable)
{
  int colour = _colour_gradient[button_colour][2];
 
  DrawFrameRect(x, y, x + SETTING_BUTTON_WIDTH - 1, y + SETTING_BUTTON_HEIGHT - 1, button_colour, state ? FR_LOWERED : FR_NONE);
  DrawSprite(SPR_ARROW_DOWN, PAL_NONE, x + (SETTING_BUTTON_WIDTH - NWidgetScrollbar::GetVerticalDimension().width) / 2 + state, y + 2 + state);
 
  if (!clickable) {
    GfxFillRect(x +  1, y, x + SETTING_BUTTON_WIDTH - 1, y + SETTING_BUTTON_HEIGHT - 2, colour, FILLRECT_CHECKER);
  }
}
 
void DrawBoolButton(int x, int y, bool state, bool clickable)
{
  static const Colours _bool_ctabs[2][2] = {{COLOUR_CREAM, COLOUR_RED}, {COLOUR_DARK_GREEN, COLOUR_GREEN}};
  DrawFrameRect(x, y, x + SETTING_BUTTON_WIDTH - 1, y + SETTING_BUTTON_HEIGHT - 1, _bool_ctabs[state][clickable], state ? FR_LOWERED : FR_NONE);
}
 
struct CustomCurrencyWindow : Window {
  int query_widget;
 
  CustomCurrencyWindow(WindowDesc *desc) : Window(desc)
  {
    this->InitNested();
 
    SetButtonState();
  }
 
  void SetButtonState()
  {
    this->SetWidgetDisabledState(WID_CC_RATE_DOWN, _custom_currency.rate == 1);
    this->SetWidgetDisabledState(WID_CC_RATE_UP, _custom_currency.rate == UINT16_MAX);
    this->SetWidgetDisabledState(WID_CC_YEAR_DOWN, _custom_currency.to_euro == CF_NOEURO);
    this->SetWidgetDisabledState(WID_CC_YEAR_UP, _custom_currency.to_euro == MAX_YEAR);
  }
 
  void SetStringParameters(int widget) const override
  {
    switch (widget) {
      case WID_CC_RATE:      SetDParam(0, 1); SetDParam(1, 1);            break;
      case WID_CC_SEPARATOR: SetDParamStr(0, _custom_currency.separator); break;
      case WID_CC_PREFIX:    SetDParamStr(0, _custom_currency.prefix);    break;
      case WID_CC_SUFFIX:    SetDParamStr(0, _custom_currency.suffix);    break;
      case WID_CC_YEAR:
        SetDParam(0, (_custom_currency.to_euro != CF_NOEURO) ? STR_CURRENCY_SWITCH_TO_EURO : STR_CURRENCY_SWITCH_TO_EURO_NEVER);
        SetDParam(1, _custom_currency.to_euro);
        break;
 
      case WID_CC_PREVIEW:
        SetDParam(0, 10000);
        break;
    }
  }
 
  void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize) override
  {
    switch (widget) {
      /* Set the appropriate width for the edit 'buttons' */
      case WID_CC_SEPARATOR_EDIT:
      case WID_CC_PREFIX_EDIT:
      case WID_CC_SUFFIX_EDIT:
        size->width  = this->GetWidget<NWidgetBase>(WID_CC_RATE_DOWN)->smallest_x + this->GetWidget<NWidgetBase>(WID_CC_RATE_UP)->smallest_x;
        break;
 
      /* Make sure the window is wide enough for the widest exchange rate */
      case WID_CC_RATE:
        SetDParam(0, 1);
        SetDParam(1, INT32_MAX);
        *size = GetStringBoundingBox(STR_CURRENCY_EXCHANGE_RATE);
        break;
    }
  }
 
  void OnClick(Point pt, int widget, int click_count) override
  {
    int line = 0;
    int len = 0;
    StringID str = 0;
    CharSetFilter afilter = CS_ALPHANUMERAL;
 
    switch (widget) {
      case WID_CC_RATE_DOWN:
        if (_custom_currency.rate > 1) _custom_currency.rate--;
        if (_custom_currency.rate == 1) this->DisableWidget(WID_CC_RATE_DOWN);
        this->EnableWidget(WID_CC_RATE_UP);
        break;
 
      case WID_CC_RATE_UP:
        if (_custom_currency.rate < UINT16_MAX) _custom_currency.rate++;
        if (_custom_currency.rate == UINT16_MAX) this->DisableWidget(WID_CC_RATE_UP);
        this->EnableWidget(WID_CC_RATE_DOWN);
        break;
 
      case WID_CC_RATE:
        SetDParam(0, _custom_currency.rate);
        str = STR_JUST_INT;
        len = 5;
        line = WID_CC_RATE;
        afilter = CS_NUMERAL;
        break;
 
      case WID_CC_SEPARATOR_EDIT:
      case WID_CC_SEPARATOR:
        SetDParamStr(0, _custom_currency.separator);
        str = STR_JUST_RAW_STRING;
        len = 1;
        line = WID_CC_SEPARATOR;
        break;
 
      case WID_CC_PREFIX_EDIT:
      case WID_CC_PREFIX:
        SetDParamStr(0, _custom_currency.prefix);
        str = STR_JUST_RAW_STRING;
        len = 12;
        line = WID_CC_PREFIX;
        break;
 
      case WID_CC_SUFFIX_EDIT:
      case WID_CC_SUFFIX:
        SetDParamStr(0, _custom_currency.suffix);
        str = STR_JUST_RAW_STRING;
        len = 12;
        line = WID_CC_SUFFIX;
        break;
 
      case WID_CC_YEAR_DOWN:
        _custom_currency.to_euro = (_custom_currency.to_euro <= 2000) ? CF_NOEURO : _custom_currency.to_euro - 1;
        if (_custom_currency.to_euro == CF_NOEURO) this->DisableWidget(WID_CC_YEAR_DOWN);
        this->EnableWidget(WID_CC_YEAR_UP);
        break;
 
      case WID_CC_YEAR_UP:
        _custom_currency.to_euro = Clamp(_custom_currency.to_euro + 1, 2000, MAX_YEAR);
        if (_custom_currency.to_euro == MAX_YEAR) this->DisableWidget(WID_CC_YEAR_UP);
        this->EnableWidget(WID_CC_YEAR_DOWN);
        break;
 
      case WID_CC_YEAR:
        SetDParam(0, _custom_currency.to_euro);
        str = STR_JUST_INT;
        len = 7;
        line = WID_CC_YEAR;
        afilter = CS_NUMERAL;
        break;
    }
 
    if (len != 0) {
      this->query_widget = line;
      ShowQueryString(str, STR_CURRENCY_CHANGE_PARAMETER, len + 1, this, afilter, QSF_NONE);
    }
 
    this->SetTimeout();
    this->SetDirty();
  }
 
  void OnQueryTextFinished(char *str) override
  {
    if (str == nullptr) return;
 
    switch (this->query_widget) {
      case WID_CC_RATE:
        _custom_currency.rate = Clamp(atoi(str), 1, UINT16_MAX);
        break;
 
      case WID_CC_SEPARATOR: // Thousands separator
        strecpy(_custom_currency.separator, str, lastof(_custom_currency.separator));
        break;
 
      case WID_CC_PREFIX:
        strecpy(_custom_currency.prefix, str, lastof(_custom_currency.prefix));
        break;
 
      case WID_CC_SUFFIX:
        strecpy(_custom_currency.suffix, str, lastof(_custom_currency.suffix));
        break;
 
      case WID_CC_YEAR: { // Year to switch to euro
        int val = atoi(str);
 
        _custom_currency.to_euro = (val < 2000 ? CF_NOEURO : std::min(val, MAX_YEAR));
        break;
      }
    }
    MarkWholeScreenDirty();
    SetButtonState();
  }
 
  void OnTimeout() override
  {
    this->SetDirty();
  }
};
 
static const NWidgetPart _nested_cust_currency_widgets[] = {
  NWidget(NWID_HORIZONTAL),
    NWidget(WWT_CLOSEBOX, COLOUR_GREY),
    NWidget(WWT_CAPTION, COLOUR_GREY), SetDataTip(STR_CURRENCY_WINDOW, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
  EndContainer(),
  NWidget(WWT_PANEL, COLOUR_GREY),
    NWidget(NWID_VERTICAL, NC_EQUALSIZE), SetPIP(7, 3, 0),
      NWidget(NWID_HORIZONTAL), SetPIP(10, 0, 5),
        NWidget(WWT_PUSHARROWBTN, COLOUR_YELLOW, WID_CC_RATE_DOWN), SetDataTip(AWV_DECREASE, STR_CURRENCY_DECREASE_EXCHANGE_RATE_TOOLTIP),
        NWidget(WWT_PUSHARROWBTN, COLOUR_YELLOW, WID_CC_RATE_UP), SetDataTip(AWV_INCREASE, STR_CURRENCY_INCREASE_EXCHANGE_RATE_TOOLTIP),
        NWidget(NWID_SPACER), SetMinimalSize(5, 0),
        NWidget(WWT_TEXT, COLOUR_BLUE, WID_CC_RATE), SetDataTip(STR_CURRENCY_EXCHANGE_RATE, STR_CURRENCY_SET_EXCHANGE_RATE_TOOLTIP), SetFill(1, 0),
      EndContainer(),
      NWidget(NWID_HORIZONTAL), SetPIP(10, 0, 5),
        NWidget(WWT_PUSHBTN, COLOUR_DARK_BLUE, WID_CC_SEPARATOR_EDIT), SetDataTip(0x0, STR_CURRENCY_SET_CUSTOM_CURRENCY_SEPARATOR_TOOLTIP), SetFill(0, 1),
        NWidget(NWID_SPACER), SetMinimalSize(5, 0),
        NWidget(WWT_TEXT, COLOUR_BLUE, WID_CC_SEPARATOR), SetDataTip(STR_CURRENCY_SEPARATOR, STR_CURRENCY_SET_CUSTOM_CURRENCY_SEPARATOR_TOOLTIP), SetFill(1, 0),
      EndContainer(),
      NWidget(NWID_HORIZONTAL), SetPIP(10, 0, 5),
        NWidget(WWT_PUSHBTN, COLOUR_DARK_BLUE, WID_CC_PREFIX_EDIT), SetDataTip(0x0, STR_CURRENCY_SET_CUSTOM_CURRENCY_PREFIX_TOOLTIP), SetFill(0, 1),
        NWidget(NWID_SPACER), SetMinimalSize(5, 0),
        NWidget(WWT_TEXT, COLOUR_BLUE, WID_CC_PREFIX), SetDataTip(STR_CURRENCY_PREFIX, STR_CURRENCY_SET_CUSTOM_CURRENCY_PREFIX_TOOLTIP), SetFill(1, 0),
      EndContainer(),
      NWidget(NWID_HORIZONTAL), SetPIP(10, 0, 5),
        NWidget(WWT_PUSHBTN, COLOUR_DARK_BLUE, WID_CC_SUFFIX_EDIT), SetDataTip(0x0, STR_CURRENCY_SET_CUSTOM_CURRENCY_SUFFIX_TOOLTIP), SetFill(0, 1),
        NWidget(NWID_SPACER), SetMinimalSize(5, 0),
        NWidget(WWT_TEXT, COLOUR_BLUE, WID_CC_SUFFIX), SetDataTip(STR_CURRENCY_SUFFIX, STR_CURRENCY_SET_CUSTOM_CURRENCY_SUFFIX_TOOLTIP), SetFill(1, 0),
      EndContainer(),
      NWidget(NWID_HORIZONTAL), SetPIP(10, 0, 5),
        NWidget(WWT_PUSHARROWBTN, COLOUR_YELLOW, WID_CC_YEAR_DOWN), SetDataTip(AWV_DECREASE, STR_CURRENCY_DECREASE_CUSTOM_CURRENCY_TO_EURO_TOOLTIP),
        NWidget(WWT_PUSHARROWBTN, COLOUR_YELLOW, WID_CC_YEAR_UP), SetDataTip(AWV_INCREASE, STR_CURRENCY_INCREASE_CUSTOM_CURRENCY_TO_EURO_TOOLTIP),
        NWidget(NWID_SPACER), SetMinimalSize(5, 0),
        NWidget(WWT_TEXT, COLOUR_BLUE, WID_CC_YEAR), SetDataTip(STR_JUST_STRING, STR_CURRENCY_SET_CUSTOM_CURRENCY_TO_EURO_TOOLTIP), SetFill(1, 0),
      EndContainer(),
    EndContainer(),
    NWidget(WWT_LABEL, COLOUR_BLUE, WID_CC_PREVIEW),
                SetDataTip(STR_CURRENCY_PREVIEW, STR_CURRENCY_CUSTOM_CURRENCY_PREVIEW_TOOLTIP), SetPadding(15, 1, 18, 2),
  EndContainer(),
};
 
static WindowDesc _cust_currency_desc(
  WDP_CENTER, nullptr, 0, 0,
  WC_CUSTOM_CURRENCY, WC_NONE,
  0,
  _nested_cust_currency_widgets, lengthof(_nested_cust_currency_widgets)
);
 
static void ShowCustCurrency()
{
  DeleteWindowById(WC_CUSTOM_CURRENCY, 0);
  new CustomCurrencyWindow(&_cust_currency_desc);
}