Change: Let AI developers edit non-editable AI/Game Script Parameters (#8895)

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

/*
 * This file is part of OpenTTD.
 * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
 * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */

/** @file station_gui.cpp The GUI for stations. */

#include "stdafx.h"
#include "debug.h"
#include "gui.h"
#include "textbuf_gui.h"
#include "company_func.h"
#include "command_func.h"
#include "vehicle_gui.h"
#include "cargotype.h"
#include "station_gui.h"
#include "strings_func.h"
#include "string_func.h"
#include "window_func.h"
#include "viewport_func.h"
#include "widgets/dropdown_func.h"
#include "station_base.h"
#include "waypoint_base.h"
#include "tilehighlight_func.h"
#include "company_base.h"
#include "sortlist_type.h"
#include "core/geometry_func.hpp"
#include "vehiclelist.h"
#include "town.h"
#include "linkgraph/linkgraph.h"
#include "zoom_func.h"
#include "station_cmd.h"

#include "widgets/station_widget.h"

#include "table/strings.h"

#include <set>
#include <vector>

#include "safeguards.h"

/**
 * Calculates and draws the accepted or supplied cargo around the selected tile(s)
 * @param left x position where the string is to be drawn
 * @param right the right most position to draw on
 * @param top y position where the string is to be drawn
 * @param sct which type of cargo is to be displayed (passengers/non-passengers)
 * @param rad radius around selected tile(s) to be searched
 * @param supplies if supplied cargoes should be drawn, else accepted cargoes
 * @return Returns the y value below the string that was drawn
 */
int DrawStationCoverageAreaText(int left, int right, int top, StationCoverageType sct, int rad, bool supplies)
{
        TileIndex tile = TileVirtXY(_thd.pos.x, _thd.pos.y);
        CargoTypes cargo_mask = 0;
        if (_thd.drawstyle == HT_RECT && tile < MapSize()) {
                CargoArray cargoes;
                if (supplies) {
                        cargoes = GetProductionAroundTiles(tile, _thd.size.x / TILE_SIZE, _thd.size.y / TILE_SIZE, rad);
                } else {
                        cargoes = GetAcceptanceAroundTiles(tile, _thd.size.x / TILE_SIZE, _thd.size.y / TILE_SIZE, rad);
                }

                /* Convert cargo counts to a set of cargo bits, and draw the result. */
                for (CargoID i = 0; i < NUM_CARGO; i++) {
                        switch (sct) {
                                case SCT_PASSENGERS_ONLY: if (!IsCargoInClass(i, CC_PASSENGERS)) continue; break;
                                case SCT_NON_PASSENGERS_ONLY: if (IsCargoInClass(i, CC_PASSENGERS)) continue; break;
                                case SCT_ALL: break;
                                default: NOT_REACHED();
                        }
                        if (cargoes[i] >= (supplies ? 1U : 8U)) SetBit(cargo_mask, i);
                }
        }
        SetDParam(0, cargo_mask);
        return DrawStringMultiLine(left, right, top, INT32_MAX, supplies ? STR_STATION_BUILD_SUPPLIES_CARGO : STR_STATION_BUILD_ACCEPTS_CARGO);
}

/**
 * Find stations adjacent to the current tile highlight area, so that existing coverage
 * area can be drawn.
 */
static void FindStationsAroundSelection()
{
        /* With distant join we don't know which station will be selected, so don't show any */
        if (_ctrl_pressed) {
                SetViewportCatchmentStation(nullptr, true);
                return;
        }

        /* Tile area for TileHighlightData */
        TileArea location(TileVirtXY(_thd.pos.x, _thd.pos.y), _thd.size.x / TILE_SIZE - 1, _thd.size.y / TILE_SIZE - 1);

        /* Extended area by one tile */
        uint x = TileX(location.tile);
        uint y = TileY(location.tile);

        int max_c = 1;
        TileArea ta(TileXY(std::max<int>(0, x - max_c), std::max<int>(0, y - max_c)), TileXY(std::min<int>(MapMaxX(), x + location.w + max_c), std::min<int>(MapMaxY(), y + location.h + max_c)));

        Station *adjacent = nullptr;

        /* Direct loop instead of ForAllStationsAroundTiles as we are not interested in catchment area */
        for (TileIndex tile : ta) {
                if (IsTileType(tile, MP_STATION) && GetTileOwner(tile) == _local_company) {
                        Station *st = Station::GetByTile(tile);
                        if (st == nullptr) continue;
                        if (adjacent != nullptr && st != adjacent) {
                                /* Multiple nearby, distant join is required. */
                                adjacent = nullptr;
                                break;
                        }
                        adjacent = st;
                }
        }
        SetViewportCatchmentStation(adjacent, true);
}

/**
 * Check whether we need to redraw the station coverage text.
 * If it is needed actually make the window for redrawing.
 * @param w the window to check.
 */
void CheckRedrawStationCoverage(const Window *w)
{
        /* Test if ctrl state changed */
        static bool _last_ctrl_pressed;
        if (_ctrl_pressed != _last_ctrl_pressed) {
                _thd.dirty = 0xff;
                _last_ctrl_pressed = _ctrl_pressed;
        }

        if (_thd.dirty & 1) {
                _thd.dirty &= ~1;
                w->SetDirty();

                if (_settings_client.gui.station_show_coverage && _thd.drawstyle == HT_RECT) {
                        FindStationsAroundSelection();
                }
        }
}

/**
 * Draw small boxes of cargo amount and ratings data at the given
 * coordinates. If amount exceeds 576 units, it is shown 'full', same
 * goes for the rating: at above 90% orso (224) it is also 'full'
 *
 * @param left   left most coordinate to draw the box at
 * @param right  right most coordinate to draw the box at
 * @param y      coordinate to draw the box at
 * @param type   Cargo type
 * @param amount Cargo amount
 * @param rating ratings data for that particular cargo
 */
static void StationsWndShowStationRating(int left, int right, int y, CargoID type, uint amount, byte rating)
{
        static const uint units_full  = 576; ///< number of units to show station as 'full'
        static const uint rating_full = 224; ///< rating needed so it is shown as 'full'

        const CargoSpec *cs = CargoSpec::Get(type);
        if (!cs->IsValid()) return;

        int padding = ScaleFontTrad(1);
        int width = right - left;
        int colour = cs->rating_colour;
        TextColour tc = GetContrastColour(colour);
        uint w = std::min(amount + 5, units_full) * width / units_full;

        int height = GetCharacterHeight(FS_SMALL) + padding - 1;

        if (amount > 30) {
                /* Draw total cargo (limited) on station */
                GfxFillRect(left, y, left + w - 1, y + height, colour);
        } else {
                /* Draw a (scaled) one pixel-wide bar of additional cargo meter, useful
                 * for stations with only a small amount (<=30) */
                uint rest = ScaleFontTrad(amount) / 5;
                if (rest != 0) {
                        GfxFillRect(left, y + height - rest, left + padding - 1, y + height, colour);
                }
        }

        DrawString(left + padding, right, y, cs->abbrev, tc);

        /* Draw green/red ratings bar (fits under the waiting bar) */
        y += height + padding + 1;
        GfxFillRect(left + padding, y, right - padding - 1, y + padding - 1, PC_RED);
        w = std::min<uint>(rating, rating_full) * (width - padding - padding) / rating_full;
        if (w != 0) GfxFillRect(left + padding, y, left + w - 1, y + padding - 1, PC_GREEN);
}

typedef GUIList<const Station*> GUIStationList;

/**
 * The list of stations per company.
 */
class CompanyStationsWindow : public Window
{
protected:
        /* Runtime saved values */
        static Listing last_sorting;
        static byte facilities;               // types of stations of interest
        static bool include_empty;            // whether we should include stations without waiting cargo
        static const CargoTypes cargo_filter_max;
        static CargoTypes cargo_filter;           // bitmap of cargo types to include

        /* Constants for sorting stations */
        static const StringID sorter_names[];
        static GUIStationList::SortFunction * const sorter_funcs[];

        GUIStationList stations;
        Scrollbar *vscroll;
        uint rating_width;

        /**
         * (Re)Build station list
         *
         * @param owner company whose stations are to be in list
         */
        void BuildStationsList(const Owner owner)
        {
                if (!this->stations.NeedRebuild()) return;

                Debug(misc, 3, "Building station list for company {}", owner);

                this->stations.clear();

                for (const Station *st : Station::Iterate()) {
                        if (st->owner == owner || (st->owner == OWNER_NONE && HasStationInUse(st->index, true, owner))) {
                                if (this->facilities & st->facilities) { // only stations with selected facilities
                                        int num_waiting_cargo = 0;
                                        for (CargoID j = 0; j < NUM_CARGO; j++) {
                                                if (st->goods[j].HasRating()) {
                                                        num_waiting_cargo++; // count number of waiting cargo
                                                        if (HasBit(this->cargo_filter, j)) {
                                                                this->stations.push_back(st);
                                                                break;
                                                        }
                                                }
                                        }
                                        /* stations without waiting cargo */
                                        if (num_waiting_cargo == 0 && this->include_empty) {
                                                this->stations.push_back(st);
                                        }
                                }
                        }
                }

                this->stations.shrink_to_fit();
                this->stations.RebuildDone();

                this->vscroll->SetCount((uint)this->stations.size()); // Update the scrollbar
        }

        /** Sort stations by their name */
        static bool StationNameSorter(const Station * const &a, const Station * const &b)
        {
                int r = strnatcmp(a->GetCachedName(), b->GetCachedName()); // Sort by name (natural sorting).
                if (r == 0) return a->index < b->index;
                return r < 0;
        }

        /** Sort stations by their type */
        static bool StationTypeSorter(const Station * const &a, const Station * const &b)
        {
                return a->facilities < b->facilities;
        }

        /** Sort stations by their waiting cargo */
        static bool StationWaitingTotalSorter(const Station * const &a, const Station * const &b)
        {
                int diff = 0;

                for (CargoID j : SetCargoBitIterator(cargo_filter)) {
                        diff += a->goods[j].cargo.TotalCount() - b->goods[j].cargo.TotalCount();
                }

                return diff < 0;
        }

        /** Sort stations by their available waiting cargo */
        static bool StationWaitingAvailableSorter(const Station * const &a, const Station * const &b)
        {
                int diff = 0;

                for (CargoID j : SetCargoBitIterator(cargo_filter)) {
                        diff += a->goods[j].cargo.AvailableCount() - b->goods[j].cargo.AvailableCount();
                }

                return diff < 0;
        }

        /** Sort stations by their rating */
        static bool StationRatingMaxSorter(const Station * const &a, const Station * const &b)
        {
                byte maxr1 = 0;
                byte maxr2 = 0;

                for (CargoID j : SetCargoBitIterator(cargo_filter)) {
                        if (a->goods[j].HasRating()) maxr1 = std::max(maxr1, a->goods[j].rating);
                        if (b->goods[j].HasRating()) maxr2 = std::max(maxr2, b->goods[j].rating);
                }

                return maxr1 < maxr2;
        }

        /** Sort stations by their rating */
        static bool StationRatingMinSorter(const Station * const &a, const Station * const &b)
        {
                byte minr1 = 255;
                byte minr2 = 255;

                for (CargoID j = 0; j < NUM_CARGO; j++) {
                        if (!HasBit(cargo_filter, j)) continue;
                        if (a->goods[j].HasRating()) minr1 = std::min(minr1, a->goods[j].rating);
                        if (b->goods[j].HasRating()) minr2 = std::min(minr2, b->goods[j].rating);
                }

                return minr1 > minr2;
        }

        /** Sort the stations list */
        void SortStationsList()
        {
                if (!this->stations.Sort()) return;

                /* Set the modified widget dirty */
                this->SetWidgetDirty(WID_STL_LIST);
        }

public:
        CompanyStationsWindow(WindowDesc *desc, WindowNumber window_number) : Window(desc)
        {
                this->stations.SetListing(this->last_sorting);
                this->stations.SetSortFuncs(this->sorter_funcs);
                this->stations.ForceRebuild();
                this->stations.NeedResort();
                this->SortStationsList();

                this->CreateNestedTree();
                this->vscroll = this->GetScrollbar(WID_STL_SCROLLBAR);
                this->FinishInitNested(window_number);
                this->owner = (Owner)this->window_number;

                uint8 index = 0;
                for (const CargoSpec *cs : _sorted_standard_cargo_specs) {
                        if (HasBit(this->cargo_filter, cs->Index())) {
                                this->LowerWidget(WID_STL_CARGOSTART + index);
                        }
                        index++;
                }

                if (this->cargo_filter == this->cargo_filter_max) this->cargo_filter = _cargo_mask;

                for (uint i = 0; i < 5; i++) {
                        if (HasBit(this->facilities, i)) this->LowerWidget(i + WID_STL_TRAIN);
                }
                this->SetWidgetLoweredState(WID_STL_NOCARGOWAITING, this->include_empty);

                this->GetWidget<NWidgetCore>(WID_STL_SORTDROPBTN)->widget_data = this->sorter_names[this->stations.SortType()];
        }

        ~CompanyStationsWindow()
        {
                this->last_sorting = this->stations.GetListing();
        }

        void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize) override
        {
                switch (widget) {
                        case WID_STL_SORTBY: {
                                Dimension d = GetStringBoundingBox(this->GetWidget<NWidgetCore>(widget)->widget_data);
                                d.width += padding.width + Window::SortButtonWidth() * 2; // Doubled since the string is centred and it also looks better.
                                d.height += padding.height;
                                *size = maxdim(*size, d);
                                break;
                        }

                        case WID_STL_SORTDROPBTN: {
                                Dimension d = {0, 0};
                                for (int i = 0; this->sorter_names[i] != INVALID_STRING_ID; i++) {
                                        d = maxdim(d, GetStringBoundingBox(this->sorter_names[i]));
                                }
                                d.width += padding.width;
                                d.height += padding.height;
                                *size = maxdim(*size, d);
                                break;
                        }

                        case WID_STL_LIST:
                                resize->height = std::max(FONT_HEIGHT_NORMAL, FONT_HEIGHT_SMALL + ScaleFontTrad(3));
                                size->height = WD_FRAMERECT_TOP + 5 * resize->height + WD_FRAMERECT_BOTTOM;

                                /* Determine appropriate width for mini station rating graph */
                                this->rating_width = 0;
                                for (const CargoSpec *cs : _sorted_standard_cargo_specs) {
                                        this->rating_width = std::max(this->rating_width, GetStringBoundingBox(cs->abbrev).width);
                                }
                                /* Approximately match original 16 pixel wide rating bars by multiplying string width by 1.6 */
                                this->rating_width = this->rating_width * 16 / 10;
                                break;

                        default:
                                if (widget >= WID_STL_CARGOSTART) {
                                        Dimension d = GetStringBoundingBox(_sorted_cargo_specs[widget - WID_STL_CARGOSTART]->abbrev);
                                        d.width  += padding.width + 2;
                                        d.height += padding.height;
                                        *size = maxdim(*size, d);
                                }
                                break;
                }
        }

        void OnPaint() override
        {
                this->BuildStationsList((Owner)this->window_number);
                this->SortStationsList();

                this->DrawWidgets();
        }

        void DrawWidget(const Rect &r, int widget) const override
        {
                switch (widget) {
                        case WID_STL_SORTBY:
                                /* draw arrow pointing up/down for ascending/descending sorting */
                                this->DrawSortButtonState(WID_STL_SORTBY, this->stations.IsDescSortOrder() ? SBS_DOWN : SBS_UP);
                                break;

                        case WID_STL_LIST: {
                                bool rtl = _current_text_dir == TD_RTL;
                                int max = std::min<size_t>(this->vscroll->GetPosition() + this->vscroll->GetCapacity(), this->stations.size());
                                int y = r.top + WD_FRAMERECT_TOP;
                                uint line_height = this->GetWidget<NWidgetBase>(widget)->resize_y;
                                /* Spacing between station name and first rating graph. */
                                int text_spacing = ScaleFontTrad(5);
                                /* Spacing between additional rating graphs. */
                                int rating_spacing = ScaleFontTrad(4);

                                for (int i = this->vscroll->GetPosition(); i < max; ++i) { // do until max number of stations of owner
                                        const Station *st = this->stations[i];
                                        assert(st->xy != INVALID_TILE);

                                        /* Do not do the complex check HasStationInUse here, it may be even false
                                         * when the order had been removed and the station list hasn't been removed yet */
                                        assert(st->owner == owner || st->owner == OWNER_NONE);

                                        SetDParam(0, st->index);
                                        SetDParam(1, st->facilities);
                                        int x = DrawString(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, y + (line_height - FONT_HEIGHT_NORMAL) / 2, STR_STATION_LIST_STATION);
                                        x += rtl ? -text_spacing : text_spacing;

                                        /* show cargo waiting and station ratings */
                                        for (const CargoSpec *cs : _sorted_standard_cargo_specs) {
                                                CargoID cid = cs->Index();
                                                if (st->goods[cid].cargo.TotalCount() > 0) {
                                                        /* For RTL we work in exactly the opposite direction. So
                                                         * decrement the space needed first, then draw to the left
                                                         * instead of drawing to the left and then incrementing
                                                         * the space. */
                                                        if (rtl) {
                                                                x -= rating_width + rating_spacing;
                                                                if (x < r.left + WD_FRAMERECT_LEFT) break;
                                                        }
                                                        StationsWndShowStationRating(x, x + rating_width, y, cid, st->goods[cid].cargo.TotalCount(), st->goods[cid].rating);
                                                        if (!rtl) {
                                                                x += rating_width + rating_spacing;
                                                                if (x > r.right - WD_FRAMERECT_RIGHT) break;
                                                        }
                                                }
                                        }
                                        y += line_height;
                                }

                                if (this->vscroll->GetCount() == 0) { // company has no stations
                                        DrawString(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, y, STR_STATION_LIST_NONE);
                                        return;
                                }
                                break;
                        }

                        default:
                                if (widget >= WID_STL_CARGOSTART) {
                                        const CargoSpec *cs = _sorted_cargo_specs[widget - WID_STL_CARGOSTART];
                                        int cg_ofst = HasBit(this->cargo_filter, cs->Index()) ? 1 : 0;
                                        GfxFillRect(r.left + cg_ofst + 1, r.top + cg_ofst + 1, r.right - 1 + cg_ofst, r.bottom - 1 + cg_ofst, cs->rating_colour);
                                        TextColour tc = GetContrastColour(cs->rating_colour);
                                        DrawString(r.left + cg_ofst, r.right + cg_ofst, r.top + (r.bottom - r.top - FONT_HEIGHT_SMALL) / 2 + cg_ofst, cs->abbrev, tc, SA_HOR_CENTER);
                                }
                                break;
                }
        }

        void SetStringParameters(int widget) const override
        {
                if (widget == WID_STL_CAPTION) {
                        SetDParam(0, this->window_number);
                        SetDParam(1, this->vscroll->GetCount());
                }
        }

        void OnClick(Point pt, int widget, int click_count) override
        {
                switch (widget) {
                        case WID_STL_LIST: {
                                uint id_v = this->vscroll->GetScrolledRowFromWidget(pt.y, this, WID_STL_LIST);
                                if (id_v >= this->stations.size()) return; // click out of list bound

                                const Station *st = this->stations[id_v];
                                /* do not check HasStationInUse - it is slow and may be invalid */
                                assert(st->owner == (Owner)this->window_number || st->owner == OWNER_NONE);

                                if (_ctrl_pressed) {
                                        ShowExtraViewportWindow(st->xy);
                                } else {
                                        ScrollMainWindowToTile(st->xy);
                                }
                                break;
                        }

                        case WID_STL_TRAIN:
                        case WID_STL_TRUCK:
                        case WID_STL_BUS:
                        case WID_STL_AIRPLANE:
                        case WID_STL_SHIP:
                                if (_ctrl_pressed) {
                                        ToggleBit(this->facilities, widget - WID_STL_TRAIN);
                                        this->ToggleWidgetLoweredState(widget);
                                } else {
                                        for (uint i : SetBitIterator(this->facilities)) {
                                                this->RaiseWidget(i + WID_STL_TRAIN);
                                        }
                                        this->facilities = 1 << (widget - WID_STL_TRAIN);
                                        this->LowerWidget(widget);
                                }
                                this->stations.ForceRebuild();
                                this->SetDirty();
                                break;

                        case WID_STL_FACILALL:
                                for (uint i = WID_STL_TRAIN; i <= WID_STL_SHIP; i++) {
                                        this->LowerWidget(i);
                                }

                                this->facilities = FACIL_TRAIN | FACIL_TRUCK_STOP | FACIL_BUS_STOP | FACIL_AIRPORT | FACIL_DOCK;
                                this->stations.ForceRebuild();
                                this->SetDirty();
                                break;

                        case WID_STL_CARGOALL: {
                                for (uint i = 0; i < _sorted_standard_cargo_specs.size(); i++) {
                                        this->LowerWidget(WID_STL_CARGOSTART + i);
                                }
                                this->LowerWidget(WID_STL_NOCARGOWAITING);

                                this->cargo_filter = _cargo_mask;
                                this->include_empty = true;
                                this->stations.ForceRebuild();
                                this->SetDirty();
                                break;
                        }

                        case WID_STL_SORTBY: // flip sorting method asc/desc
                                this->stations.ToggleSortOrder();
                                this->SetDirty();
                                break;

                        case WID_STL_SORTDROPBTN: // select sorting criteria dropdown menu
                                ShowDropDownMenu(this, this->sorter_names, this->stations.SortType(), WID_STL_SORTDROPBTN, 0, 0);
                                break;

                        case WID_STL_NOCARGOWAITING:
                                if (_ctrl_pressed) {
                                        this->include_empty = !this->include_empty;
                                        this->ToggleWidgetLoweredState(WID_STL_NOCARGOWAITING);
                                } else {
                                        for (uint i = 0; i < _sorted_standard_cargo_specs.size(); i++) {
                                                this->RaiseWidget(WID_STL_CARGOSTART + i);
                                        }

                                        this->cargo_filter = 0;
                                        this->include_empty = true;

                                        this->LowerWidget(WID_STL_NOCARGOWAITING);
                                }
                                this->stations.ForceRebuild();
                                this->SetDirty();
                                break;

                        default:
                                if (widget >= WID_STL_CARGOSTART) { // change cargo_filter
                                        /* Determine the selected cargo type */
                                        const CargoSpec *cs = _sorted_cargo_specs[widget - WID_STL_CARGOSTART];

                                        if (_ctrl_pressed) {
                                                ToggleBit(this->cargo_filter, cs->Index());
                                                this->ToggleWidgetLoweredState(widget);
                                        } else {
                                                for (uint i = 0; i < _sorted_standard_cargo_specs.size(); i++) {
                                                        this->RaiseWidget(WID_STL_CARGOSTART + i);
                                                }
                                                this->RaiseWidget(WID_STL_NOCARGOWAITING);

                                                this->cargo_filter = 0;
                                                this->include_empty = false;

                                                SetBit(this->cargo_filter, cs->Index());
                                                this->LowerWidget(widget);
                                        }
                                        this->stations.ForceRebuild();
                                        this->SetDirty();
                                }
                                break;
                }
        }

        void OnDropdownSelect(int widget, int index) override
        {
                if (this->stations.SortType() != index) {
                        this->stations.SetSortType(index);

                        /* Display the current sort variant */
                        this->GetWidget<NWidgetCore>(WID_STL_SORTDROPBTN)->widget_data = this->sorter_names[this->stations.SortType()];

                        this->SetDirty();
                }
        }

        void OnGameTick() override
        {
                if (this->stations.NeedResort()) {
                        Debug(misc, 3, "Periodic rebuild station list company {}", this->window_number);
                        this->SetDirty();
                }
        }

        void OnResize() override
        {
                this->vscroll->SetCapacityFromWidget(this, WID_STL_LIST, WD_FRAMERECT_TOP + WD_FRAMERECT_BOTTOM);
        }

        /**
         * Some data on this window has become invalid.
         * @param data Information about the changed data.
         * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
         */
        void OnInvalidateData(int data = 0, bool gui_scope = true) override
        {
                if (data == 0) {
                        /* This needs to be done in command-scope to enforce rebuilding before resorting invalid data */
                        this->stations.ForceRebuild();
                } else {
                        this->stations.ForceResort();
                }
        }
};

Listing CompanyStationsWindow::last_sorting = {false, 0};
byte CompanyStationsWindow::facilities = FACIL_TRAIN | FACIL_TRUCK_STOP | FACIL_BUS_STOP | FACIL_AIRPORT | FACIL_DOCK;
bool CompanyStationsWindow::include_empty = true;
const CargoTypes CompanyStationsWindow::cargo_filter_max = ALL_CARGOTYPES;
CargoTypes CompanyStationsWindow::cargo_filter = ALL_CARGOTYPES;

/* Available station sorting functions */
GUIStationList::SortFunction * const CompanyStationsWindow::sorter_funcs[] = {
        &StationNameSorter,
        &StationTypeSorter,
        &StationWaitingTotalSorter,
        &StationWaitingAvailableSorter,
        &StationRatingMaxSorter,
        &StationRatingMinSorter
};

/* Names of the sorting functions */
const StringID CompanyStationsWindow::sorter_names[] = {
        STR_SORT_BY_NAME,
        STR_SORT_BY_FACILITY,
        STR_SORT_BY_WAITING_TOTAL,
        STR_SORT_BY_WAITING_AVAILABLE,
        STR_SORT_BY_RATING_MAX,
        STR_SORT_BY_RATING_MIN,
        INVALID_STRING_ID
};

/**
 * Make a horizontal row of cargo buttons, starting at widget #WID_STL_CARGOSTART.
 * @param biggest_index Pointer to store biggest used widget number of the buttons.
 * @return Horizontal row.
 */
static NWidgetBase *CargoWidgets(int *biggest_index)
{
        NWidgetHorizontal *container = new NWidgetHorizontal();

        for (uint i = 0; i < _sorted_standard_cargo_specs.size(); i++) {
                NWidgetBackground *panel = new NWidgetBackground(WWT_PANEL, COLOUR_GREY, WID_STL_CARGOSTART + i);
                panel->SetMinimalSize(14, 0);
                panel->SetMinimalTextLines(1, 0, FS_NORMAL);
                panel->SetResize(0, 0);
                panel->SetFill(0, 1);
                panel->SetDataTip(0, STR_STATION_LIST_USE_CTRL_TO_SELECT_MORE);
                container->Add(panel);
        }
        *biggest_index = WID_STL_CARGOSTART + static_cast<int>(_sorted_standard_cargo_specs.size());
        return container;
}

static const NWidgetPart _nested_company_stations_widgets[] = {
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_CLOSEBOX, COLOUR_GREY),
                NWidget(WWT_CAPTION, COLOUR_GREY, WID_STL_CAPTION), SetDataTip(STR_STATION_LIST_CAPTION, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
                NWidget(WWT_SHADEBOX, COLOUR_GREY),
                NWidget(WWT_DEFSIZEBOX, COLOUR_GREY),
                NWidget(WWT_STICKYBOX, COLOUR_GREY),
        EndContainer(),
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_STL_TRAIN), SetMinimalSize(14, 0), SetMinimalTextLines(1, 0), SetDataTip(STR_TRAIN, STR_STATION_LIST_USE_CTRL_TO_SELECT_MORE), SetFill(0, 1),
                NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_STL_TRUCK), SetMinimalSize(14, 0), SetMinimalTextLines(1, 0), SetDataTip(STR_LORRY, STR_STATION_LIST_USE_CTRL_TO_SELECT_MORE), SetFill(0, 1),
                NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_STL_BUS), SetMinimalSize(14, 0), SetMinimalTextLines(1, 0), SetDataTip(STR_BUS, STR_STATION_LIST_USE_CTRL_TO_SELECT_MORE), SetFill(0, 1),
                NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_STL_SHIP), SetMinimalSize(14, 0), SetMinimalTextLines(1, 0), SetDataTip(STR_SHIP, STR_STATION_LIST_USE_CTRL_TO_SELECT_MORE), SetFill(0, 1),
                NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_STL_AIRPLANE), SetMinimalSize(14, 0), SetMinimalTextLines(1, 0), SetDataTip(STR_PLANE, STR_STATION_LIST_USE_CTRL_TO_SELECT_MORE), SetFill(0, 1),
                NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_STL_FACILALL), SetMinimalSize(14, 0), SetMinimalTextLines(1, 0), SetDataTip(STR_ABBREV_ALL, STR_STATION_LIST_SELECT_ALL_FACILITIES), SetFill(0, 1),
                NWidget(WWT_PANEL, COLOUR_GREY), SetMinimalSize(5, 0), SetFill(0, 1), EndContainer(),
                NWidgetFunction(CargoWidgets),
                NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_STL_NOCARGOWAITING), SetMinimalSize(14, 0), SetMinimalTextLines(1, 0), SetDataTip(STR_ABBREV_NONE, STR_STATION_LIST_NO_WAITING_CARGO), SetFill(0, 1),
                NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_STL_CARGOALL), SetMinimalSize(14, 0), SetMinimalTextLines(1, 0), SetDataTip(STR_ABBREV_ALL, STR_STATION_LIST_SELECT_ALL_TYPES), SetFill(0, 1),
                NWidget(WWT_PANEL, COLOUR_GREY), SetResize(1, 0), SetFill(1, 1), EndContainer(),
        EndContainer(),
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_STL_SORTBY), SetMinimalSize(81, 12), SetDataTip(STR_BUTTON_SORT_BY, STR_TOOLTIP_SORT_ORDER),
                NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_STL_SORTDROPBTN), SetMinimalSize(163, 12), SetDataTip(STR_SORT_BY_NAME, STR_TOOLTIP_SORT_CRITERIA), // widget_data gets overwritten.
                NWidget(WWT_PANEL, COLOUR_GREY), SetResize(1, 0), SetFill(1, 1), EndContainer(),
        EndContainer(),
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_PANEL, COLOUR_GREY, WID_STL_LIST), SetMinimalSize(346, 125), SetResize(1, 10), SetDataTip(0x0, STR_STATION_LIST_TOOLTIP), SetScrollbar(WID_STL_SCROLLBAR), EndContainer(),
                NWidget(NWID_VERTICAL),
                        NWidget(NWID_VSCROLLBAR, COLOUR_GREY, WID_STL_SCROLLBAR),
                        NWidget(WWT_RESIZEBOX, COLOUR_GREY),
                EndContainer(),
        EndContainer(),
};

static WindowDesc _company_stations_desc(
        WDP_AUTO, "list_stations", 358, 162,
        WC_STATION_LIST, WC_NONE,
        0,
        _nested_company_stations_widgets, lengthof(_nested_company_stations_widgets)
);

/**
 * Opens window with list of company's stations
 *
 * @param company whose stations' list show
 */
void ShowCompanyStations(CompanyID company)
{
        if (!Company::IsValidID(company)) return;

        AllocateWindowDescFront<CompanyStationsWindow>(&_company_stations_desc, company);
}

static const NWidgetPart _nested_station_view_widgets[] = {
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_CLOSEBOX, COLOUR_GREY),
                NWidget(WWT_PUSHIMGBTN, COLOUR_GREY, WID_SV_RENAME), SetMinimalSize(12, 14), SetDataTip(SPR_RENAME, STR_STATION_VIEW_RENAME_TOOLTIP),
                NWidget(WWT_CAPTION, COLOUR_GREY, WID_SV_CAPTION), SetDataTip(STR_STATION_VIEW_CAPTION, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
                NWidget(WWT_PUSHIMGBTN, COLOUR_GREY, WID_SV_LOCATION), SetMinimalSize(12, 14), SetDataTip(SPR_GOTO_LOCATION, STR_STATION_VIEW_CENTER_TOOLTIP),
                NWidget(WWT_SHADEBOX, COLOUR_GREY),
                NWidget(WWT_DEFSIZEBOX, COLOUR_GREY),
                NWidget(WWT_STICKYBOX, COLOUR_GREY),
        EndContainer(),
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_SV_GROUP), SetMinimalSize(81, 12), SetFill(1, 1), SetDataTip(STR_STATION_VIEW_GROUP, 0x0),
                NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_SV_GROUP_BY), SetMinimalSize(168, 12), SetResize(1, 0), SetFill(0, 1), SetDataTip(0x0, STR_TOOLTIP_GROUP_ORDER),
        EndContainer(),
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_SV_SORT_ORDER), SetMinimalSize(81, 12), SetFill(1, 1), SetDataTip(STR_BUTTON_SORT_BY, STR_TOOLTIP_SORT_ORDER),
                NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_SV_SORT_BY), SetMinimalSize(168, 12), SetResize(1, 0), SetFill(0, 1), SetDataTip(0x0, STR_TOOLTIP_SORT_CRITERIA),
        EndContainer(),
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_PANEL, COLOUR_GREY, WID_SV_WAITING), SetMinimalSize(237, 44), SetResize(1, 10), SetScrollbar(WID_SV_SCROLLBAR), EndContainer(),
                NWidget(NWID_VSCROLLBAR, COLOUR_GREY, WID_SV_SCROLLBAR),
        EndContainer(),
        NWidget(WWT_PANEL, COLOUR_GREY, WID_SV_ACCEPT_RATING_LIST), SetMinimalSize(249, 23), SetResize(1, 0), EndContainer(),
        NWidget(NWID_HORIZONTAL, NC_EQUALSIZE),
                NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_SV_ACCEPTS_RATINGS), SetMinimalSize(46, 12), SetResize(1, 0), SetFill(1, 1),
                                SetDataTip(STR_STATION_VIEW_RATINGS_BUTTON, STR_STATION_VIEW_RATINGS_TOOLTIP),
                NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_SV_CLOSE_AIRPORT), SetMinimalSize(45, 12), SetResize(1, 0), SetFill(1, 1),
                                SetDataTip(STR_STATION_VIEW_CLOSE_AIRPORT, STR_STATION_VIEW_CLOSE_AIRPORT_TOOLTIP),
                NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_SV_CATCHMENT), SetMinimalSize(45, 12), SetResize(1, 0), SetFill(1, 1), SetDataTip(STR_BUTTON_CATCHMENT, STR_TOOLTIP_CATCHMENT),
                NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_SV_TRAINS), SetMinimalSize(14, 12), SetFill(0, 1), SetDataTip(STR_TRAIN, STR_STATION_VIEW_SCHEDULED_TRAINS_TOOLTIP),
                NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_SV_ROADVEHS), SetMinimalSize(14, 12), SetFill(0, 1), SetDataTip(STR_LORRY, STR_STATION_VIEW_SCHEDULED_ROAD_VEHICLES_TOOLTIP),
                NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_SV_SHIPS), SetMinimalSize(14, 12), SetFill(0, 1), SetDataTip(STR_SHIP, STR_STATION_VIEW_SCHEDULED_SHIPS_TOOLTIP),
                NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_SV_PLANES),  SetMinimalSize(14, 12), SetFill(0, 1), SetDataTip(STR_PLANE, STR_STATION_VIEW_SCHEDULED_AIRCRAFT_TOOLTIP),
                NWidget(WWT_RESIZEBOX, COLOUR_GREY),
        EndContainer(),
};

/**
 * Draws icons of waiting cargo in the StationView window
 *
 * @param i type of cargo
 * @param waiting number of waiting units
 * @param left  left most coordinate to draw on
 * @param right right most coordinate to draw on
 * @param y y coordinate
 */
static void DrawCargoIcons(CargoID i, uint waiting, int left, int right, int y)
{
        int width = ScaleGUITrad(10);
        uint num = std::min<uint>((waiting + (width / 2)) / width, (right - left) / width); // maximum is width / 10 icons so it won't overflow
        if (num == 0) return;

        SpriteID sprite = CargoSpec::Get(i)->GetCargoIcon();

        int x = _current_text_dir == TD_RTL ? left : right - num * width;
        do {
                DrawSprite(sprite, PAL_NONE, x, y);
                x += width;
        } while (--num);
}

enum SortOrder {
        SO_DESCENDING,
        SO_ASCENDING
};

class CargoDataEntry;

enum CargoSortType {
        ST_AS_GROUPING,    ///< by the same principle the entries are being grouped
        ST_COUNT,          ///< by amount of cargo
        ST_STATION_STRING, ///< by station name
        ST_STATION_ID,     ///< by station id
        ST_CARGO_ID,       ///< by cargo id
};

class CargoSorter {
public:
        CargoSorter(CargoSortType t = ST_STATION_ID, SortOrder o = SO_ASCENDING) : type(t), order(o) {}
        CargoSortType GetSortType() {return this->type;}
        bool operator()(const CargoDataEntry *cd1, const CargoDataEntry *cd2) const;

private:
        CargoSortType type;
        SortOrder order;

        template<class Tid>
        bool SortId(Tid st1, Tid st2) const;
        bool SortCount(const CargoDataEntry *cd1, const CargoDataEntry *cd2) const;
        bool SortStation (StationID st1, StationID st2) const;
};

typedef std::set<CargoDataEntry *, CargoSorter> CargoDataSet;

/**
 * A cargo data entry representing one possible row in the station view window's
 * top part. Cargo data entries form a tree where each entry can have several
 * children. Parents keep track of the sums of their childrens' cargo counts.
 */
class CargoDataEntry {
public:
        CargoDataEntry();
        ~CargoDataEntry();

        /**
         * Insert a new child or retrieve an existing child using a station ID as ID.
         * @param station ID of the station for which an entry shall be created or retrieved
         * @return a child entry associated with the given station.
         */
        CargoDataEntry *InsertOrRetrieve(StationID station)
        {
                return this->InsertOrRetrieve<StationID>(station);
        }

        /**
         * Insert a new child or retrieve an existing child using a cargo ID as ID.
         * @param cargo ID of the cargo for which an entry shall be created or retrieved
         * @return a child entry associated with the given cargo.
         */
        CargoDataEntry *InsertOrRetrieve(CargoID cargo)
        {
                return this->InsertOrRetrieve<CargoID>(cargo);
        }

        void Update(uint count);

        /**
         * Remove a child associated with the given station.
         * @param station ID of the station for which the child should be removed.
         */
        void Remove(StationID station)
        {
                CargoDataEntry t(station);
                this->Remove(&t);
        }

        /**
         * Remove a child associated with the given cargo.
         * @param cargo ID of the cargo for which the child should be removed.
         */
        void Remove(CargoID cargo)
        {
                CargoDataEntry t(cargo);
                this->Remove(&t);
        }

        /**
         * Retrieve a child for the given station. Return nullptr if it doesn't exist.
         * @param station ID of the station the child we're looking for is associated with.
         * @return a child entry for the given station or nullptr.
         */
        CargoDataEntry *Retrieve(StationID station) const
        {
                CargoDataEntry t(station);
                return this->Retrieve(this->children->find(&t));
        }

        /**
         * Retrieve a child for the given cargo. Return nullptr if it doesn't exist.
         * @param cargo ID of the cargo the child we're looking for is associated with.
         * @return a child entry for the given cargo or nullptr.
         */
        CargoDataEntry *Retrieve(CargoID cargo) const
        {
                CargoDataEntry t(cargo);
                return this->Retrieve(this->children->find(&t));
        }

        void Resort(CargoSortType type, SortOrder order);

        /**
         * Get the station ID for this entry.
         */
        StationID GetStation() const { return this->station; }

        /**
         * Get the cargo ID for this entry.
         */
        CargoID GetCargo() const { return this->cargo; }

        /**
         * Get the cargo count for this entry.
         */
        uint GetCount() const { return this->count; }

        /**
         * Get the parent entry for this entry.
         */
        CargoDataEntry *GetParent() const { return this->parent; }

        /**
         * Get the number of children for this entry.
         */
        uint GetNumChildren() const { return this->num_children; }

        /**
         * Get an iterator pointing to the begin of the set of children.
         */
        CargoDataSet::iterator Begin() const { return this->children->begin(); }

        /**
         * Get an iterator pointing to the end of the set of children.
         */
        CargoDataSet::iterator End() const { return this->children->end(); }

        /**
         * Has this entry transfers.
         */
        bool HasTransfers() const { return this->transfers; }

        /**
         * Set the transfers state.
         */
        void SetTransfers(bool value) { this->transfers = value; }

        void Clear();
private:

        CargoDataEntry(StationID st, uint c, CargoDataEntry *p);
        CargoDataEntry(CargoID car, uint c, CargoDataEntry *p);
        CargoDataEntry(StationID st);
        CargoDataEntry(CargoID car);

        CargoDataEntry *Retrieve(CargoDataSet::iterator i) const;

        template<class Tid>
        CargoDataEntry *InsertOrRetrieve(Tid s);

        void Remove(CargoDataEntry *comp);
        void IncrementSize();

        CargoDataEntry *parent;   ///< the parent of this entry.
        const union {
                StationID station;    ///< ID of the station this entry is associated with.
                struct {
                        CargoID cargo;    ///< ID of the cargo this entry is associated with.
                        bool transfers;   ///< If there are transfers for this cargo.
                };
        };
        uint num_children;        ///< the number of subentries belonging to this entry.
        uint count;               ///< sum of counts of all children or amount of cargo for this entry.
        CargoDataSet *children;   ///< the children of this entry.
};

CargoDataEntry::CargoDataEntry() :
        parent(nullptr),
        station(INVALID_STATION),
        num_children(0),
        count(0),
        children(new CargoDataSet(CargoSorter(ST_CARGO_ID)))
{}

CargoDataEntry::CargoDataEntry(CargoID cargo, uint count, CargoDataEntry *parent) :
        parent(parent),
        cargo(cargo),
        num_children(0),
        count(count),
        children(new CargoDataSet)
{}

CargoDataEntry::CargoDataEntry(StationID station, uint count, CargoDataEntry *parent) :
        parent(parent),
        station(station),
        num_children(0),
        count(count),
        children(new CargoDataSet)
{}

CargoDataEntry::CargoDataEntry(StationID station) :
        parent(nullptr),
        station(station),
        num_children(0),
        count(0),
        children(nullptr)
{}

CargoDataEntry::CargoDataEntry(CargoID cargo) :
        parent(nullptr),
        cargo(cargo),
        num_children(0),
        count(0),
        children(nullptr)
{}

CargoDataEntry::~CargoDataEntry()
{
        this->Clear();
        delete this->children;
}

/**
 * Delete all subentries, reset count and num_children and adapt parent's count.
 */
void CargoDataEntry::Clear()
{
        if (this->children != nullptr) {
                for (CargoDataSet::iterator i = this->children->begin(); i != this->children->end(); ++i) {
                        assert(*i != this);
                        delete *i;
                }
                this->children->clear();
        }
        if (this->parent != nullptr) this->parent->count -= this->count;
        this->count = 0;
        this->num_children = 0;
}

/**
 * Remove a subentry from this one and delete it.
 * @param child the entry to be removed. This may also be a synthetic entry
 * which only contains the ID of the entry to be removed. In this case child is
 * not deleted.
 */
void CargoDataEntry::Remove(CargoDataEntry *child)
{
        CargoDataSet::iterator i = this->children->find(child);
        if (i != this->children->end()) {
                delete *i;
                this->children->erase(i);
        }
}

/**
 * Retrieve a subentry or insert it if it doesn't exist, yet.
 * @tparam ID type of ID: either StationID or CargoID
 * @param child_id ID of the child to be inserted or retrieved.
 * @return the new or retrieved subentry
 */
template<class Tid>
CargoDataEntry *CargoDataEntry::InsertOrRetrieve(Tid child_id)
{
        CargoDataEntry tmp(child_id);
        CargoDataSet::iterator i = this->children->find(&tmp);
        if (i == this->children->end()) {
                IncrementSize();
                return *(this->children->insert(new CargoDataEntry(child_id, 0, this)).first);
        } else {
                CargoDataEntry *ret = *i;
                assert(this->children->value_comp().GetSortType() != ST_COUNT);
                return ret;
        }
}

/**
 * Update the count for this entry and propagate the change to the parent entry
 * if there is one.
 * @param count the amount to be added to this entry
 */
void CargoDataEntry::Update(uint count)
{
        this->count += count;
        if (this->parent != nullptr) this->parent->Update(count);
}

/**
 * Increment
 */
void CargoDataEntry::IncrementSize()
{
         ++this->num_children;
         if (this->parent != nullptr) this->parent->IncrementSize();
}

void CargoDataEntry::Resort(CargoSortType type, SortOrder order)
{
        CargoDataSet *new_subs = new CargoDataSet(this->children->begin(), this->children->end(), CargoSorter(type, order));
        delete this->children;
        this->children = new_subs;
}

CargoDataEntry *CargoDataEntry::Retrieve(CargoDataSet::iterator i) const
{
        if (i == this->children->end()) {
                return nullptr;
        } else {
                assert(this->children->value_comp().GetSortType() != ST_COUNT);
                return *i;
        }
}

bool CargoSorter::operator()(const CargoDataEntry *cd1, const CargoDataEntry *cd2) const
{
        switch (this->type) {
                case ST_STATION_ID:
                        return this->SortId<StationID>(cd1->GetStation(), cd2->GetStation());
                case ST_CARGO_ID:
                        return this->SortId<CargoID>(cd1->GetCargo(), cd2->GetCargo());
                case ST_COUNT:
                        return this->SortCount(cd1, cd2);
                case ST_STATION_STRING:
                        return this->SortStation(cd1->GetStation(), cd2->GetStation());
                default:
                        NOT_REACHED();
        }
}

template<class Tid>
bool CargoSorter::SortId(Tid st1, Tid st2) const
{
        return (this->order == SO_ASCENDING) ? st1 < st2 : st2 < st1;
}

bool CargoSorter::SortCount(const CargoDataEntry *cd1, const CargoDataEntry *cd2) const
{
        uint c1 = cd1->GetCount();
        uint c2 = cd2->GetCount();
        if (c1 == c2) {
                return this->SortStation(cd1->GetStation(), cd2->GetStation());
        } else if (this->order == SO_ASCENDING) {
                return c1 < c2;
        } else {
                return c2 < c1;
        }
}

bool CargoSorter::SortStation(StationID st1, StationID st2) const
{
        if (!Station::IsValidID(st1)) {
                return Station::IsValidID(st2) ? this->order == SO_ASCENDING : this->SortId(st1, st2);
        } else if (!Station::IsValidID(st2)) {
                return order == SO_DESCENDING;
        }

        int res = strnatcmp(Station::Get(st1)->GetCachedName(), Station::Get(st2)->GetCachedName()); // Sort by name (natural sorting).
        if (res == 0) {
                return this->SortId(st1, st2);
        } else {
                return (this->order == SO_ASCENDING) ? res < 0 : res > 0;
        }
}

/**
 * The StationView window
 */
struct StationViewWindow : public Window {
        /**
         * A row being displayed in the cargo view (as opposed to being "hidden" behind a plus sign).
         */
        struct RowDisplay {
                RowDisplay(CargoDataEntry *f, StationID n) : filter(f), next_station(n) {}
                RowDisplay(CargoDataEntry *f, CargoID n) : filter(f), next_cargo(n) {}

                /**
                 * Parent of the cargo entry belonging to the row.
                 */
                CargoDataEntry *filter;
                union {
                        /**
                         * ID of the station belonging to the entry actually displayed if it's to/from/via.
                         */
                        StationID next_station;

                        /**
                         * ID of the cargo belonging to the entry actually displayed if it's cargo.
                         */
                        CargoID next_cargo;
                };
        };

        typedef std::vector<RowDisplay> CargoDataVector;

        static const int NUM_COLUMNS = 4; ///< Number of "columns" in the cargo view: cargo, from, via, to

        /**
         * Type of data invalidation.
         */
        enum Invalidation {
                INV_FLOWS = 0x100, ///< The planned flows have been recalculated and everything has to be updated.
                INV_CARGO = 0x200  ///< Some cargo has been added or removed.
        };

        /**
         * Type of grouping used in each of the "columns".
         */
        enum Grouping {
                GR_SOURCE,      ///< Group by source of cargo ("from").
                GR_NEXT,        ///< Group by next station ("via").
                GR_DESTINATION, ///< Group by estimated final destination ("to").
                GR_CARGO,       ///< Group by cargo type.
        };

        /**
         * Display mode of the cargo view.
         */
        enum Mode {
                MODE_WAITING, ///< Show cargo waiting at the station.
                MODE_PLANNED  ///< Show cargo planned to pass through the station.
        };

        uint expand_shrink_width;     ///< The width allocated to the expand/shrink 'button'
        int rating_lines;             ///< Number of lines in the cargo ratings view.
        int accepts_lines;            ///< Number of lines in the accepted cargo view.
        Scrollbar *vscroll;

        /** Height of the #WID_SV_ACCEPT_RATING_LIST widget for different views. */
        enum AcceptListHeight {
                ALH_RATING  = 13, ///< Height of the cargo ratings view.
                ALH_ACCEPTS = 3,  ///< Height of the accepted cargo view.
        };

        static const StringID _sort_names[];  ///< Names of the sorting options in the dropdown.
        static const StringID _group_names[]; ///< Names of the grouping options in the dropdown.

        /**
         * Sort types of the different 'columns'.
         * In fact only ST_COUNT and ST_AS_GROUPING are active and you can only
         * sort all the columns in the same way. The other options haven't been
         * included in the GUI due to lack of space.
         */
        CargoSortType sortings[NUM_COLUMNS];

        /** Sort order (ascending/descending) for the 'columns'. */
        SortOrder sort_orders[NUM_COLUMNS];

        int scroll_to_row;                  ///< If set, scroll the main viewport to the station pointed to by this row.
        int grouping_index;                 ///< Currently selected entry in the grouping drop down.
        Mode current_mode;                  ///< Currently selected display mode of cargo view.
        Grouping groupings[NUM_COLUMNS];    ///< Grouping modes for the different columns.

        CargoDataEntry expanded_rows;       ///< Parent entry of currently expanded rows.
        CargoDataEntry cached_destinations; ///< Cache for the flows passing through this station.
        CargoDataVector displayed_rows;     ///< Parent entry of currently displayed rows (including collapsed ones).

        StationViewWindow(WindowDesc *desc, WindowNumber window_number) : Window(desc),
                scroll_to_row(INT_MAX), grouping_index(0)
        {
                this->rating_lines  = ALH_RATING;
                this->accepts_lines = ALH_ACCEPTS;

                this->CreateNestedTree();
                this->vscroll = this->GetScrollbar(WID_SV_SCROLLBAR);
                /* Nested widget tree creation is done in two steps to ensure that this->GetWidget<NWidgetCore>(WID_SV_ACCEPTS_RATINGS) exists in UpdateWidgetSize(). */
                this->FinishInitNested(window_number);

                this->groupings[0] = GR_CARGO;
                this->sortings[0] = ST_AS_GROUPING;
                this->SelectGroupBy(_settings_client.gui.station_gui_group_order);
                this->SelectSortBy(_settings_client.gui.station_gui_sort_by);
                this->sort_orders[0] = SO_ASCENDING;
                this->SelectSortOrder((SortOrder)_settings_client.gui.station_gui_sort_order);
                this->owner = Station::Get(window_number)->owner;
        }

        void Close() override
        {
                CloseWindowById(WC_TRAINS_LIST,   VehicleListIdentifier(VL_STATION_LIST, VEH_TRAIN,    this->owner, this->window_number).Pack(), false);
                CloseWindowById(WC_ROADVEH_LIST,  VehicleListIdentifier(VL_STATION_LIST, VEH_ROAD,     this->owner, this->window_number).Pack(), false);
                CloseWindowById(WC_SHIPS_LIST,    VehicleListIdentifier(VL_STATION_LIST, VEH_SHIP,     this->owner, this->window_number).Pack(), false);
                CloseWindowById(WC_AIRCRAFT_LIST, VehicleListIdentifier(VL_STATION_LIST, VEH_AIRCRAFT, this->owner, this->window_number).Pack(), false);

                SetViewportCatchmentStation(Station::Get(this->window_number), false);
                this->Window::Close();
        }

        /**
         * Show a certain cargo entry characterized by source/next/dest station, cargo ID and amount of cargo at the
         * right place in the cargo view. I.e. update as many rows as are expanded following that characterization.
         * @param data Root entry of the tree.
         * @param cargo Cargo ID of the entry to be shown.
         * @param source Source station of the entry to be shown.
         * @param next Next station the cargo to be shown will visit.
         * @param dest Final destination of the cargo to be shown.
         * @param count Amount of cargo to be shown.
         */
        void ShowCargo(CargoDataEntry *data, CargoID cargo, StationID source, StationID next, StationID dest, uint count)
        {
                if (count == 0) return;
                bool auto_distributed = _settings_game.linkgraph.GetDistributionType(cargo) != DT_MANUAL;
                const CargoDataEntry *expand = &this->expanded_rows;
                for (int i = 0; i < NUM_COLUMNS && expand != nullptr; ++i) {
                        switch (groupings[i]) {
                                case GR_CARGO:
                                        assert(i == 0);
                                        data = data->InsertOrRetrieve(cargo);
                                        data->SetTransfers(source != this->window_number);
                                        expand = expand->Retrieve(cargo);
                                        break;
                                case GR_SOURCE:
                                        if (auto_distributed || source != this->window_number) {
                                                data = data->InsertOrRetrieve(source);
                                                expand = expand->Retrieve(source);
                                        }
                                        break;
                                case GR_NEXT:
                                        if (auto_distributed) {
                                                data = data->InsertOrRetrieve(next);
                                                expand = expand->Retrieve(next);
                                        }
                                        break;
                                case GR_DESTINATION:
                                        if (auto_distributed) {
                                                data = data->InsertOrRetrieve(dest);
                                                expand = expand->Retrieve(dest);
                                        }
                                        break;
                        }
                }
                data->Update(count);
        }

        void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize) override
        {
                switch (widget) {
                        case WID_SV_WAITING:
                                resize->height = FONT_HEIGHT_NORMAL;
                                size->height = WD_FRAMERECT_TOP + 4 * resize->height + WD_FRAMERECT_BOTTOM;
                                this->expand_shrink_width = std::max(GetStringBoundingBox("-").width, GetStringBoundingBox("+").width) + WD_FRAMERECT_LEFT + WD_FRAMERECT_RIGHT;
                                break;

                        case WID_SV_ACCEPT_RATING_LIST:
                                size->height = WD_FRAMERECT_TOP + ((this->GetWidget<NWidgetCore>(WID_SV_ACCEPTS_RATINGS)->widget_data == STR_STATION_VIEW_RATINGS_BUTTON) ? this->accepts_lines : this->rating_lines) * FONT_HEIGHT_NORMAL + WD_FRAMERECT_BOTTOM;
                                break;

                        case WID_SV_CLOSE_AIRPORT:
                                if (!(Station::Get(this->window_number)->facilities & FACIL_AIRPORT)) {
                                        /* Hide 'Close Airport' button if no airport present. */
                                        size->width = 0;
                                        resize->width = 0;
                                        fill->width = 0;
                                }
                                break;
                }
        }

        void OnPaint() override
        {
                const Station *st = Station::Get(this->window_number);
                CargoDataEntry cargo;
                BuildCargoList(&cargo, st);

                this->vscroll->SetCount(cargo.GetNumChildren()); // update scrollbar

                /* disable some buttons */
                this->SetWidgetDisabledState(WID_SV_RENAME,   st->owner != _local_company);
                this->SetWidgetDisabledState(WID_SV_TRAINS,   !(st->facilities & FACIL_TRAIN));
                this->SetWidgetDisabledState(WID_SV_ROADVEHS, !(st->facilities & FACIL_TRUCK_STOP) && !(st->facilities & FACIL_BUS_STOP));
                this->SetWidgetDisabledState(WID_SV_SHIPS,    !(st->facilities & FACIL_DOCK));
                this->SetWidgetDisabledState(WID_SV_PLANES,   !(st->facilities & FACIL_AIRPORT));
                this->SetWidgetDisabledState(WID_SV_CLOSE_AIRPORT, !(st->facilities & FACIL_AIRPORT) || st->owner != _local_company || st->owner == OWNER_NONE); // Also consider SE, where _local_company == OWNER_NONE
                this->SetWidgetLoweredState(WID_SV_CLOSE_AIRPORT, (st->facilities & FACIL_AIRPORT) && (st->airport.flags & AIRPORT_CLOSED_block) != 0);

                extern const Station *_viewport_highlight_station;
                this->SetWidgetDisabledState(WID_SV_CATCHMENT, st->facilities == FACIL_NONE);
                this->SetWidgetLoweredState(WID_SV_CATCHMENT, _viewport_highlight_station == st);

                this->DrawWidgets();

                if (!this->IsShaded()) {
                        /* Draw 'accepted cargo' or 'cargo ratings'. */
                        const NWidgetBase *wid = this->GetWidget<NWidgetBase>(WID_SV_ACCEPT_RATING_LIST);
                        const Rect r = wid->GetCurrentRect();
                        if (this->GetWidget<NWidgetCore>(WID_SV_ACCEPTS_RATINGS)->widget_data == STR_STATION_VIEW_RATINGS_BUTTON) {
                                int lines = this->DrawAcceptedCargo(r);
                                if (lines > this->accepts_lines) { // Resize the widget, and perform re-initialization of the window.
                                        this->accepts_lines = lines;
                                        this->ReInit();
                                        return;
                                }
                        } else {
                                int lines = this->DrawCargoRatings(r);
                                if (lines > this->rating_lines) { // Resize the widget, and perform re-initialization of the window.
                                        this->rating_lines = lines;
                                        this->ReInit();
                                        return;
                                }
                        }

                        /* Draw arrow pointing up/down for ascending/descending sorting */
                        this->DrawSortButtonState(WID_SV_SORT_ORDER, sort_orders[1] == SO_ASCENDING ? SBS_UP : SBS_DOWN);

                        int pos = this->vscroll->GetPosition();

                        int maxrows = this->vscroll->GetCapacity();

                        displayed_rows.clear();

                        /* Draw waiting cargo. */
                        NWidgetBase *nwi = this->GetWidget<NWidgetBase>(WID_SV_WAITING);
                        Rect waiting_rect = nwi->GetCurrentRect();
                        this->DrawEntries(&cargo, waiting_rect, pos, maxrows, 0);
                        scroll_to_row = INT_MAX;
                }
        }

        void SetStringParameters(int widget) const override
        {
                const Station *st = Station::Get(this->window_number);
                SetDParam(0, st->index);
                SetDParam(1, st->facilities);
        }

        /**
         * Rebuild the cache for estimated destinations which is used to quickly show the "destination" entries
         * even if we actually don't know the destination of a certain packet from just looking at it.
         * @param i Cargo to recalculate the cache for.
         */
        void RecalcDestinations(CargoID i)
        {
                const Station *st = Station::Get(this->window_number);
                CargoDataEntry *cargo_entry = cached_destinations.InsertOrRetrieve(i);
                cargo_entry->Clear();

                const FlowStatMap &flows = st->goods[i].flows;
                for (FlowStatMap::const_iterator it = flows.begin(); it != flows.end(); ++it) {
                        StationID from = it->first;
                        CargoDataEntry *source_entry = cargo_entry->InsertOrRetrieve(from);
                        const FlowStat::SharesMap *shares = it->second.GetShares();
                        uint32 prev_count = 0;
                        for (FlowStat::SharesMap::const_iterator flow_it = shares->begin(); flow_it != shares->end(); ++flow_it) {
                                StationID via = flow_it->second;
                                CargoDataEntry *via_entry = source_entry->InsertOrRetrieve(via);
                                if (via == this->window_number) {
                                        via_entry->InsertOrRetrieve(via)->Update(flow_it->first - prev_count);
                                } else {
                                        EstimateDestinations(i, from, via, flow_it->first - prev_count, via_entry);
                                }
                                prev_count = flow_it->first;
                        }
                }
        }

        /**
         * Estimate the amounts of cargo per final destination for a given cargo, source station and next hop and
         * save the result as children of the given CargoDataEntry.
         * @param cargo ID of the cargo to estimate destinations for.
         * @param source Source station of the given batch of cargo.
         * @param next Intermediate hop to start the calculation at ("next hop").
         * @param count Size of the batch of cargo.
         * @param dest CargoDataEntry to save the results in.
         */
        void EstimateDestinations(CargoID cargo, StationID source, StationID next, uint count, CargoDataEntry *dest)
        {
                if (Station::IsValidID(next) && Station::IsValidID(source)) {
                        CargoDataEntry tmp;
                        const FlowStatMap &flowmap = Station::Get(next)->goods[cargo].flows;
                        FlowStatMap::const_iterator map_it = flowmap.find(source);
                        if (map_it != flowmap.end()) {
                                const FlowStat::SharesMap *shares = map_it->second.GetShares();
                                uint32 prev_count = 0;
                                for (FlowStat::SharesMap::const_iterator i = shares->begin(); i != shares->end(); ++i) {
                                        tmp.InsertOrRetrieve(i->second)->Update(i->first - prev_count);
                                        prev_count = i->first;
                                }
                        }

                        if (tmp.GetCount() == 0) {
                                dest->InsertOrRetrieve(INVALID_STATION)->Update(count);
                        } else {
                                uint sum_estimated = 0;
                                while (sum_estimated < count) {
                                        for (CargoDataSet::iterator i = tmp.Begin(); i != tmp.End() && sum_estimated < count; ++i) {
                                                CargoDataEntry *child = *i;
                                                uint estimate = DivideApprox(child->GetCount() * count, tmp.GetCount());
                                                if (estimate == 0) estimate = 1;

                                                sum_estimated += estimate;
                                                if (sum_estimated > count) {
                                                        estimate -= sum_estimated - count;
                                                        sum_estimated = count;
                                                }

                                                if (estimate > 0) {
                                                        if (child->GetStation() == next) {
                                                                dest->InsertOrRetrieve(next)->Update(estimate);
                                                        } else {
                                                                EstimateDestinations(cargo, source, child->GetStation(), estimate, dest);
                                                        }
                                                }
                                        }

                                }
                        }
                } else {
                        dest->InsertOrRetrieve(INVALID_STATION)->Update(count);
                }
        }

        /**
         * Build up the cargo view for PLANNED mode and a specific cargo.
         * @param i Cargo to show.
         * @param flows The current station's flows for that cargo.
         * @param cargo The CargoDataEntry to save the results in.
         */
        void BuildFlowList(CargoID i, const FlowStatMap &flows, CargoDataEntry *cargo)
        {
                const CargoDataEntry *source_dest = this->cached_destinations.Retrieve(i);
                for (FlowStatMap::const_iterator it = flows.begin(); it != flows.end(); ++it) {
                        StationID from = it->first;
                        const CargoDataEntry *source_entry = source_dest->Retrieve(from);
                        const FlowStat::SharesMap *shares = it->second.GetShares();
                        for (FlowStat::SharesMap::const_iterator flow_it = shares->begin(); flow_it != shares->end(); ++flow_it) {
                                const CargoDataEntry *via_entry = source_entry->Retrieve(flow_it->second);
                                for (CargoDataSet::iterator dest_it = via_entry->Begin(); dest_it != via_entry->End(); ++dest_it) {
                                        CargoDataEntry *dest_entry = *dest_it;
                                        ShowCargo(cargo, i, from, flow_it->second, dest_entry->GetStation(), dest_entry->GetCount());
                                }
                        }
                }
        }

        /**
         * Build up the cargo view for WAITING mode and a specific cargo.
         * @param i Cargo to show.
         * @param packets The current station's cargo list for that cargo.
         * @param cargo The CargoDataEntry to save the result in.
         */
        void BuildCargoList(CargoID i, const StationCargoList &packets, CargoDataEntry *cargo)
        {
                const CargoDataEntry *source_dest = this->cached_destinations.Retrieve(i);
                for (StationCargoList::ConstIterator it = packets.Packets()->begin(); it != packets.Packets()->end(); it++) {
                        const CargoPacket *cp = *it;
                        StationID next = it.GetKey();

                        const CargoDataEntry *source_entry = source_dest->Retrieve(cp->SourceStation());
                        if (source_entry == nullptr) {
                                this->ShowCargo(cargo, i, cp->SourceStation(), next, INVALID_STATION, cp->Count());
                                continue;
                        }

                        const CargoDataEntry *via_entry = source_entry->Retrieve(next);
                        if (via_entry == nullptr) {
                                this->ShowCargo(cargo, i, cp->SourceStation(), next, INVALID_STATION, cp->Count());
                                continue;
                        }

                        for (CargoDataSet::iterator dest_it = via_entry->Begin(); dest_it != via_entry->End(); ++dest_it) {
                                CargoDataEntry *dest_entry = *dest_it;
                                uint val = DivideApprox(cp->Count() * dest_entry->GetCount(), via_entry->GetCount());
                                this->ShowCargo(cargo, i, cp->SourceStation(), next, dest_entry->GetStation(), val);
                        }
                }
                this->ShowCargo(cargo, i, NEW_STATION, NEW_STATION, NEW_STATION, packets.ReservedCount());
        }

        /**
         * Build up the cargo view for all cargoes.
         * @param cargo The root cargo entry to save all results in.
         * @param st The station to calculate the cargo view from.
         */
        void BuildCargoList(CargoDataEntry *cargo, const Station *st)
        {
                for (CargoID i = 0; i < NUM_CARGO; i++) {

                        if (this->cached_destinations.Retrieve(i) == nullptr) {
                                this->RecalcDestinations(i);
                        }

                        if (this->current_mode == MODE_WAITING) {
                                this->BuildCargoList(i, st->goods[i].cargo, cargo);
                        } else {
                                this->BuildFlowList(i, st->goods[i].flows, cargo);
                        }
                }
        }

        /**
         * Mark a specific row, characterized by its CargoDataEntry, as expanded.
         * @param data The row to be marked as expanded.
         */
        void SetDisplayedRow(const CargoDataEntry *data)
        {
                std::list<StationID> stations;
                const CargoDataEntry *parent = data->GetParent();
                if (parent->GetParent() == nullptr) {
                        this->displayed_rows.push_back(RowDisplay(&this->expanded_rows, data->GetCargo()));
                        return;
                }

                StationID next = data->GetStation();
                while (parent->GetParent()->GetParent() != nullptr) {
                        stations.push_back(parent->GetStation());
                        parent = parent->GetParent();
                }

                CargoID cargo = parent->GetCargo();
                CargoDataEntry *filter = this->expanded_rows.Retrieve(cargo);
                while (!stations.empty()) {
                        filter = filter->Retrieve(stations.back());
                        stations.pop_back();
                }

                this->displayed_rows.push_back(RowDisplay(filter, next));
        }

        /**
         * Select the correct string for an entry referring to the specified station.
         * @param station Station the entry is showing cargo for.
         * @param here String to be shown if the entry refers to the same station as this station GUI belongs to.
         * @param other_station String to be shown if the entry refers to a specific other station.
         * @param any String to be shown if the entry refers to "any station".
         * @return One of the three given strings or STR_STATION_VIEW_RESERVED, depending on what station the entry refers to.
         */
        StringID GetEntryString(StationID station, StringID here, StringID other_station, StringID any)
        {
                if (station == this->window_number) {
                        return here;
                } else if (station == INVALID_STATION) {
                        return any;
                } else if (station == NEW_STATION) {
                        return STR_STATION_VIEW_RESERVED;
                } else {
                        SetDParam(2, station);
                        return other_station;
                }
        }

        /**
         * Determine if we need to show the special "non-stop" string.
         * @param cd Entry we are going to show.
         * @param station Station the entry refers to.
         * @param column The "column" the entry will be shown in.
         * @return either STR_STATION_VIEW_VIA or STR_STATION_VIEW_NONSTOP.
         */
        StringID SearchNonStop(CargoDataEntry *cd, StationID station, int column)
        {
                CargoDataEntry *parent = cd->GetParent();
                for (int i = column - 1; i > 0; --i) {
                        if (this->groupings[i] == GR_DESTINATION) {
                                if (parent->GetStation() == station) {
                                        return STR_STATION_VIEW_NONSTOP;
                                } else {
                                        return STR_STATION_VIEW_VIA;
                                }
                        }
                        parent = parent->GetParent();
                }

                if (this->groupings[column + 1] == GR_DESTINATION) {
                        CargoDataSet::iterator begin = cd->Begin();
                        CargoDataSet::iterator end = cd->End();
                        if (begin != end && ++(cd->Begin()) == end && (*(begin))->GetStation() == station) {
                                return STR_STATION_VIEW_NONSTOP;
                        } else {
                                return STR_STATION_VIEW_VIA;
                        }
                }

                return STR_STATION_VIEW_VIA;
        }

        /**
         * Draw the given cargo entries in the station GUI.
         * @param entry Root entry for all cargo to be drawn.
         * @param r Screen rectangle to draw into.
         * @param pos Current row to be drawn to (counted down from 0 to -maxrows, same as vscroll->GetPosition()).
         * @param maxrows Maximum row to be drawn.
         * @param column Current "column" being drawn.
         * @param cargo Current cargo being drawn (if cargo column has been passed).
         * @return row (in "pos" counting) after the one we have last drawn to.
         */
        int DrawEntries(CargoDataEntry *entry, Rect &r, int pos, int maxrows, int column, CargoID cargo = CT_INVALID)
        {
                if (this->sortings[column] == ST_AS_GROUPING) {
                        if (this->groupings[column] != GR_CARGO) {
                                entry->Resort(ST_STATION_STRING, this->sort_orders[column]);
                        }
                } else {
                        entry->Resort(ST_COUNT, this->sort_orders[column]);
                }
                for (CargoDataSet::iterator i = entry->Begin(); i != entry->End(); ++i) {
                        CargoDataEntry *cd = *i;

                        Grouping grouping = this->groupings[column];
                        if (grouping == GR_CARGO) cargo = cd->GetCargo();
                        bool auto_distributed = _settings_game.linkgraph.GetDistributionType(cargo) != DT_MANUAL;

                        if (pos > -maxrows && pos <= 0) {
                                StringID str = STR_EMPTY;
                                int y = r.top + WD_FRAMERECT_TOP - pos * FONT_HEIGHT_NORMAL;
                                SetDParam(0, cargo);
                                SetDParam(1, cd->GetCount());

                                if (this->groupings[column] == GR_CARGO) {
                                        str = STR_STATION_VIEW_WAITING_CARGO;
                                        DrawCargoIcons(cd->GetCargo(), cd->GetCount(), r.left + WD_FRAMERECT_LEFT + this->expand_shrink_width, r.right - WD_FRAMERECT_RIGHT - this->expand_shrink_width, y);
                                } else {
                                        if (!auto_distributed) grouping = GR_SOURCE;
                                        StationID station = cd->GetStation();

                                        switch (grouping) {
                                                case GR_SOURCE:
                                                        str = this->GetEntryString(station, STR_STATION_VIEW_FROM_HERE, STR_STATION_VIEW_FROM, STR_STATION_VIEW_FROM_ANY);
                                                        break;
                                                case GR_NEXT:
                                                        str = this->GetEntryString(station, STR_STATION_VIEW_VIA_HERE, STR_STATION_VIEW_VIA, STR_STATION_VIEW_VIA_ANY);
                                                        if (str == STR_STATION_VIEW_VIA) str = this->SearchNonStop(cd, station, column);
                                                        break;
                                                case GR_DESTINATION:
                                                        str = this->GetEntryString(station, STR_STATION_VIEW_TO_HERE, STR_STATION_VIEW_TO, STR_STATION_VIEW_TO_ANY);
                                                        break;
                                                default:
                                                        NOT_REACHED();
                                        }
                                        if (pos == -this->scroll_to_row && Station::IsValidID(station)) {
                                                ScrollMainWindowToTile(Station::Get(station)->xy);
                                        }
                                }

                                bool rtl = _current_text_dir == TD_RTL;
                                int text_left    = rtl ? r.left + this->expand_shrink_width : r.left + WD_FRAMERECT_LEFT + column * this->expand_shrink_width;
                                int text_right   = rtl ? r.right - WD_FRAMERECT_LEFT - column * this->expand_shrink_width : r.right - this->expand_shrink_width;
                                int shrink_left  = rtl ? r.left + WD_FRAMERECT_LEFT : r.right - this->expand_shrink_width + WD_FRAMERECT_LEFT;
                                int shrink_right = rtl ? r.left + this->expand_shrink_width - WD_FRAMERECT_RIGHT : r.right - WD_FRAMERECT_RIGHT;

                                DrawString(text_left, text_right, y, str);

                                if (column < NUM_COLUMNS - 1) {
                                        const char *sym = nullptr;
                                        if (cd->GetNumChildren() > 0) {
                                                sym = "-";
                                        } else if (auto_distributed && str != STR_STATION_VIEW_RESERVED) {
                                                sym = "+";
                                        } else {
                                                /* Only draw '+' if there is something to be shown. */
                                                const StationCargoList &list = Station::Get(this->window_number)->goods[cargo].cargo;
                                                if (grouping == GR_CARGO && (list.ReservedCount() > 0 || cd->HasTransfers())) {
                                                        sym = "+";
                                                }
                                        }
                                        if (sym) DrawString(shrink_left, shrink_right, y, sym, TC_YELLOW);
                                }
                                this->SetDisplayedRow(cd);
                        }
                        --pos;
                        if (auto_distributed || column == 0) {
                                pos = this->DrawEntries(cd, r, pos, maxrows, column + 1, cargo);
                        }
                }
                return pos;
        }

        /**
         * Draw accepted cargo in the #WID_SV_ACCEPT_RATING_LIST widget.
         * @param r Rectangle of the widget.
         * @return Number of lines needed for drawing the accepted cargo.
         */
        int DrawAcceptedCargo(const Rect &r) const
        {
                const Station *st = Station::Get(this->window_number);

                CargoTypes cargo_mask = 0;
                for (CargoID i = 0; i < NUM_CARGO; i++) {
                        if (HasBit(st->goods[i].status, GoodsEntry::GES_ACCEPTANCE)) SetBit(cargo_mask, i);
                }
                SetDParam(0, cargo_mask);
                int bottom = DrawStringMultiLine(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, r.top + WD_FRAMERECT_TOP, INT32_MAX, STR_STATION_VIEW_ACCEPTS_CARGO);
                return CeilDiv(bottom - r.top - WD_FRAMERECT_TOP, FONT_HEIGHT_NORMAL);
        }

        /**
         * Draw cargo ratings in the #WID_SV_ACCEPT_RATING_LIST widget.
         * @param r Rectangle of the widget.
         * @return Number of lines needed for drawing the cargo ratings.
         */
        int DrawCargoRatings(const Rect &r) const
        {
                const Station *st = Station::Get(this->window_number);
                int y = r.top + WD_FRAMERECT_TOP;

                if (st->town->exclusive_counter > 0) {
                        SetDParam(0, st->town->exclusivity);
                        y = DrawStringMultiLine(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, y, r.bottom, st->town->exclusivity == st->owner ? STR_STATION_VIEW_EXCLUSIVE_RIGHTS_SELF : STR_STATION_VIEW_EXCLUSIVE_RIGHTS_COMPANY);
                        y += WD_PAR_VSEP_WIDE;
                }

                DrawString(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, y, STR_STATION_VIEW_SUPPLY_RATINGS_TITLE);
                y += FONT_HEIGHT_NORMAL;

                for (const CargoSpec *cs : _sorted_standard_cargo_specs) {
                        const GoodsEntry *ge = &st->goods[cs->Index()];
                        if (!ge->HasRating()) continue;

                        const LinkGraph *lg = LinkGraph::GetIfValid(ge->link_graph);
                        SetDParam(0, cs->name);
                        SetDParam(1, lg != nullptr ? lg->Monthly((*lg)[ge->node].Supply()) : 0);
                        SetDParam(2, STR_CARGO_RATING_APPALLING + (ge->rating >> 5));
                        SetDParam(3, ToPercent8(ge->rating));
                        DrawString(r.left + WD_FRAMERECT_LEFT + 6, r.right - WD_FRAMERECT_RIGHT - 6, y, STR_STATION_VIEW_CARGO_SUPPLY_RATING);
                        y += FONT_HEIGHT_NORMAL;
                }
                return CeilDiv(y - r.top - WD_FRAMERECT_TOP, FONT_HEIGHT_NORMAL);
        }

        /**
         * Expand or collapse a specific row.
         * @param filter Parent of the row.
         * @param next ID pointing to the row.
         */
        template<class Tid>
        void HandleCargoWaitingClick(CargoDataEntry *filter, Tid next)
        {
                if (filter->Retrieve(next) != nullptr) {
                        filter->Remove(next);
                } else {
                        filter->InsertOrRetrieve(next);
                }
        }

        /**
         * Handle a click on a specific row in the cargo view.
         * @param row Row being clicked.
         */
        void HandleCargoWaitingClick(int row)
        {
                if (row < 0 || (uint)row >= this->displayed_rows.size()) return;
                if (_ctrl_pressed) {
                        this->scroll_to_row = row;
                } else {
                        RowDisplay &display = this->displayed_rows[row];
                        if (display.filter == &this->expanded_rows) {
                                this->HandleCargoWaitingClick<CargoID>(display.filter, display.next_cargo);
                        } else {
                                this->HandleCargoWaitingClick<StationID>(display.filter, display.next_station);
                        }
                }
                this->SetWidgetDirty(WID_SV_WAITING);
        }

        void OnClick(Point pt, int widget, int click_count) override
        {
                switch (widget) {
                        case WID_SV_WAITING:
                                this->HandleCargoWaitingClick(this->vscroll->GetScrolledRowFromWidget(pt.y, this, WID_SV_WAITING, WD_FRAMERECT_TOP) - this->vscroll->GetPosition());
                                break;

                        case WID_SV_CATCHMENT:
                                SetViewportCatchmentStation(Station::Get(this->window_number), !this->IsWidgetLowered(WID_SV_CATCHMENT));
                                break;

                        case WID_SV_LOCATION:
                                if (_ctrl_pressed) {
                                        ShowExtraViewportWindow(Station::Get(this->window_number)->xy);
                                } else {
                                        ScrollMainWindowToTile(Station::Get(this->window_number)->xy);
                                }
                                break;

                        case WID_SV_ACCEPTS_RATINGS: {
                                /* Swap between 'accepts' and 'ratings' view. */
                                int height_change;
                                NWidgetCore *nwi = this->GetWidget<NWidgetCore>(WID_SV_ACCEPTS_RATINGS);
                                if (this->GetWidget<NWidgetCore>(WID_SV_ACCEPTS_RATINGS)->widget_data == STR_STATION_VIEW_RATINGS_BUTTON) {
                                        nwi->SetDataTip(STR_STATION_VIEW_ACCEPTS_BUTTON, STR_STATION_VIEW_ACCEPTS_TOOLTIP); // Switch to accepts view.
                                        height_change = this->rating_lines - this->accepts_lines;
                                } else {
                                        nwi->SetDataTip(STR_STATION_VIEW_RATINGS_BUTTON, STR_STATION_VIEW_RATINGS_TOOLTIP); // Switch to ratings view.
                                        height_change = this->accepts_lines - this->rating_lines;
                                }
                                this->ReInit(0, height_change * FONT_HEIGHT_NORMAL);
                                break;
                        }

                        case WID_SV_RENAME:
                                SetDParam(0, this->window_number);
                                ShowQueryString(STR_STATION_NAME, STR_STATION_VIEW_RENAME_STATION_CAPTION, MAX_LENGTH_STATION_NAME_CHARS,
                                                this, CS_ALPHANUMERAL, QSF_ENABLE_DEFAULT | QSF_LEN_IN_CHARS);
                                break;

                        case WID_SV_CLOSE_AIRPORT:
                                Command<CMD_OPEN_CLOSE_AIRPORT>::Post(this->window_number);
                                break;

                        case WID_SV_TRAINS:   // Show list of scheduled trains to this station
                        case WID_SV_ROADVEHS: // Show list of scheduled road-vehicles to this station
                        case WID_SV_SHIPS:    // Show list of scheduled ships to this station
                        case WID_SV_PLANES: { // Show list of scheduled aircraft to this station
                                Owner owner = Station::Get(this->window_number)->owner;
                                ShowVehicleListWindow(owner, (VehicleType)(widget - WID_SV_TRAINS), (StationID)this->window_number);
                                break;
                        }

                        case WID_SV_SORT_BY: {
                                /* The initial selection is composed of current mode and
                                 * sorting criteria for columns 1, 2, and 3. Column 0 is always
                                 * sorted by cargo ID. The others can theoretically be sorted
                                 * by different things but there is no UI for that. */
                                ShowDropDownMenu(this, _sort_names,
                                                this->current_mode * 2 + (this->sortings[1] == ST_COUNT ? 1 : 0),
                                                WID_SV_SORT_BY, 0, 0);
                                break;
                        }

                        case WID_SV_GROUP_BY: {
                                ShowDropDownMenu(this, _group_names, this->grouping_index, WID_SV_GROUP_BY, 0, 0);
                                break;
                        }

                        case WID_SV_SORT_ORDER: { // flip sorting method asc/desc
                                this->SelectSortOrder(this->sort_orders[1] == SO_ASCENDING ? SO_DESCENDING : SO_ASCENDING);
                                this->SetTimeout();
                                this->LowerWidget(WID_SV_SORT_ORDER);
                                break;
                        }
                }
        }

        /**
         * Select a new sort order for the cargo view.
         * @param order New sort order.
         */
        void SelectSortOrder(SortOrder order)
        {
                this->sort_orders[1] = this->sort_orders[2] = this->sort_orders[3] = order;
                _settings_client.gui.station_gui_sort_order = this->sort_orders[1];
                this->SetDirty();
        }

        /**
         * Select a new sort criterium for the cargo view.
         * @param index Row being selected in the sort criteria drop down.
         */
        void SelectSortBy(int index)
        {
                _settings_client.gui.station_gui_sort_by = index;
                switch (_sort_names[index]) {
                        case STR_STATION_VIEW_WAITING_STATION:
                                this->current_mode = MODE_WAITING;
                                this->sortings[1] = this->sortings[2] = this->sortings[3] = ST_AS_GROUPING;
                                break;
                        case STR_STATION_VIEW_WAITING_AMOUNT:
                                this->current_mode = MODE_WAITING;
                                this->sortings[1] = this->sortings[2] = this->sortings[3] = ST_COUNT;
                                break;
                        case STR_STATION_VIEW_PLANNED_STATION:
                                this->current_mode = MODE_PLANNED;
                                this->sortings[1] = this->sortings[2] = this->sortings[3] = ST_AS_GROUPING;
                                break;
                        case STR_STATION_VIEW_PLANNED_AMOUNT:
                                this->current_mode = MODE_PLANNED;
                                this->sortings[1] = this->sortings[2] = this->sortings[3] = ST_COUNT;
                                break;
                        default:
                                NOT_REACHED();
                }
                /* Display the current sort variant */
                this->GetWidget<NWidgetCore>(WID_SV_SORT_BY)->widget_data = _sort_names[index];
                this->SetDirty();
        }

        /**
         * Select a new grouping mode for the cargo view.
         * @param index Row being selected in the grouping drop down.
         */
        void SelectGroupBy(int index)
        {
                this->grouping_index = index;
                _settings_client.gui.station_gui_group_order = index;
                this->GetWidget<NWidgetCore>(WID_SV_GROUP_BY)->widget_data = _group_names[index];
                switch (_group_names[index]) {
                        case STR_STATION_VIEW_GROUP_S_V_D:
                                this->groupings[1] = GR_SOURCE;
                                this->groupings[2] = GR_NEXT;
                                this->groupings[3] = GR_DESTINATION;
                                break;
                        case STR_STATION_VIEW_GROUP_S_D_V:
                                this->groupings[1] = GR_SOURCE;
                                this->groupings[2] = GR_DESTINATION;
                                this->groupings[3] = GR_NEXT;
                                break;
                        case STR_STATION_VIEW_GROUP_V_S_D:
                                this->groupings[1] = GR_NEXT;
                                this->groupings[2] = GR_SOURCE;
                                this->groupings[3] = GR_DESTINATION;
                                break;
                        case STR_STATION_VIEW_GROUP_V_D_S:
                                this->groupings[1] = GR_NEXT;
                                this->groupings[2] = GR_DESTINATION;
                                this->groupings[3] = GR_SOURCE;
                                break;
                        case STR_STATION_VIEW_GROUP_D_S_V:
                                this->groupings[1] = GR_DESTINATION;
                                this->groupings[2] = GR_SOURCE;
                                this->groupings[3] = GR_NEXT;
                                break;
                        case STR_STATION_VIEW_GROUP_D_V_S:
                                this->groupings[1] = GR_DESTINATION;
                                this->groupings[2] = GR_NEXT;
                                this->groupings[3] = GR_SOURCE;
                                break;
                }
                this->SetDirty();
        }

        void OnDropdownSelect(int widget, int index) override
        {
                if (widget == WID_SV_SORT_BY) {
                        this->SelectSortBy(index);
                } else {
                        this->SelectGroupBy(index);
                }
        }

        void OnQueryTextFinished(char *str) override
        {
                if (str == nullptr) return;

                Command<CMD_RENAME_STATION>::Post(STR_ERROR_CAN_T_RENAME_STATION, this->window_number, str);
        }

        void OnResize() override
        {
                this->vscroll->SetCapacityFromWidget(this, WID_SV_WAITING, WD_FRAMERECT_TOP + WD_FRAMERECT_BOTTOM);
        }

        /**
         * Some data on this window has become invalid. Invalidate the cache for the given cargo if necessary.
         * @param data Information about the changed data. If it's a valid cargo ID, invalidate the cargo data.
         * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
         */
        void OnInvalidateData(int data = 0, bool gui_scope = true) override
        {
                if (gui_scope) {
                        if (data >= 0 && data < NUM_CARGO) {
                                this->cached_destinations.Remove((CargoID)data);
                        } else {
                                this->ReInit();
                        }
                }
        }
};

const StringID StationViewWindow::_sort_names[] = {
        STR_STATION_VIEW_WAITING_STATION,
        STR_STATION_VIEW_WAITING_AMOUNT,
        STR_STATION_VIEW_PLANNED_STATION,
        STR_STATION_VIEW_PLANNED_AMOUNT,
        INVALID_STRING_ID
};

const StringID StationViewWindow::_group_names[] = {
        STR_STATION_VIEW_GROUP_S_V_D,
        STR_STATION_VIEW_GROUP_S_D_V,
        STR_STATION_VIEW_GROUP_V_S_D,
        STR_STATION_VIEW_GROUP_V_D_S,
        STR_STATION_VIEW_GROUP_D_S_V,
        STR_STATION_VIEW_GROUP_D_V_S,
        INVALID_STRING_ID
};

static WindowDesc _station_view_desc(
        WDP_AUTO, "view_station", 249, 117,
        WC_STATION_VIEW, WC_NONE,
        0,
        _nested_station_view_widgets, lengthof(_nested_station_view_widgets)
);

/**
 * Opens StationViewWindow for given station
 *
 * @param station station which window should be opened
 */
void ShowStationViewWindow(StationID station)
{
        AllocateWindowDescFront<StationViewWindow>(&_station_view_desc, station);
}

/** Struct containing TileIndex and StationID */
struct TileAndStation {
        TileIndex tile;    ///< TileIndex
        StationID station; ///< StationID
};

static std::vector<TileAndStation> _deleted_stations_nearby;
static std::vector<StationID> _stations_nearby_list;

/**
 * Add station on this tile to _stations_nearby_list if it's fully within the
 * station spread.
 * @param tile Tile just being checked
 * @param user_data Pointer to TileArea context
 * @tparam T the type of station to look for
 */
template <class T>
static bool AddNearbyStation(TileIndex tile, void *user_data)
{
        TileArea *ctx = (TileArea *)user_data;

        /* First check if there were deleted stations here */
        for (uint i = 0; i < _deleted_stations_nearby.size(); i++) {
                auto ts = _deleted_stations_nearby.begin() + i;
                if (ts->tile == tile) {
                        _stations_nearby_list.push_back(_deleted_stations_nearby[i].station);
                        _deleted_stations_nearby.erase(ts);
                        i--;
                }
        }

        /* Check if own station and if we stay within station spread */
        if (!IsTileType(tile, MP_STATION)) return false;

        StationID sid = GetStationIndex(tile);

        /* This station is (likely) a waypoint */
        if (!T::IsValidID(sid)) return false;

        T *st = T::Get(sid);
        if (st->owner != _local_company || std::find(_stations_nearby_list.begin(), _stations_nearby_list.end(), sid) != _stations_nearby_list.end()) return false;

        if (st->rect.BeforeAddRect(ctx->tile, ctx->w, ctx->h, StationRect::ADD_TEST).Succeeded()) {
                _stations_nearby_list.push_back(sid);
        }

        return false; // We want to include *all* nearby stations
}

/**
 * Circulate around the to-be-built station to find stations we could join.
 * Make sure that only stations are returned where joining wouldn't exceed
 * station spread and are our own station.
 * @param ta Base tile area of the to-be-built station
 * @param distant_join Search for adjacent stations (false) or stations fully
 *                     within station spread
 * @tparam T the type of station to look for
 */
template <class T>
static const T *FindStationsNearby(TileArea ta, bool distant_join)
{
        TileArea ctx = ta;

        _stations_nearby_list.clear();
        _deleted_stations_nearby.clear();

        /* Check the inside, to return, if we sit on another station */
        for (TileIndex t : ta) {
                if (t < MapSize() && IsTileType(t, MP_STATION) && T::IsValidID(GetStationIndex(t))) return T::GetByTile(t);
        }

        /* Look for deleted stations */
        for (const BaseStation *st : BaseStation::Iterate()) {
                if (T::IsExpected(st) && !st->IsInUse() && st->owner == _local_company) {
                        /* Include only within station spread (yes, it is strictly less than) */
                        if (std::max(DistanceMax(ta.tile, st->xy), DistanceMax(TILE_ADDXY(ta.tile, ta.w - 1, ta.h - 1), st->xy)) < _settings_game.station.station_spread) {
                                _deleted_stations_nearby.push_back({st->xy, st->index});

                                /* Add the station when it's within where we're going to build */
                                if (IsInsideBS(TileX(st->xy), TileX(ctx.tile), ctx.w) &&
                                                IsInsideBS(TileY(st->xy), TileY(ctx.tile), ctx.h)) {
                                        AddNearbyStation<T>(st->xy, &ctx);
                                }
                        }
                }
        }

        /* Only search tiles where we have a chance to stay within the station spread.
         * The complete check needs to be done in the callback as we don't know the
         * extent of the found station, yet. */
        if (distant_join && std::min(ta.w, ta.h) >= _settings_game.station.station_spread) return nullptr;
        uint max_dist = distant_join ? _settings_game.station.station_spread - std::min(ta.w, ta.h) : 1;

        TileIndex tile = TileAddByDir(ctx.tile, DIR_N);
        CircularTileSearch(&tile, max_dist, ta.w, ta.h, AddNearbyStation<T>, &ctx);

        return nullptr;
}

static const NWidgetPart _nested_select_station_widgets[] = {
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_CLOSEBOX, COLOUR_DARK_GREEN),
                NWidget(WWT_CAPTION, COLOUR_DARK_GREEN, WID_JS_CAPTION), SetDataTip(STR_JOIN_STATION_CAPTION, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
                NWidget(WWT_DEFSIZEBOX, COLOUR_DARK_GREEN),
        EndContainer(),
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_PANEL, COLOUR_DARK_GREEN, WID_JS_PANEL), SetResize(1, 0), SetScrollbar(WID_JS_SCROLLBAR), EndContainer(),
                NWidget(NWID_VERTICAL),
                        NWidget(NWID_VSCROLLBAR, COLOUR_DARK_GREEN, WID_JS_SCROLLBAR),
                        NWidget(WWT_RESIZEBOX, COLOUR_DARK_GREEN),
                EndContainer(),
        EndContainer(),
};

/**
 * Window for selecting stations/waypoints to (distant) join to.
 * @tparam T The type of station to join with
 */
template <class T>
struct SelectStationWindow : Window {
        StationPickerCmdProc select_station_proc;
        TileArea area; ///< Location of new station
        Scrollbar *vscroll;

        SelectStationWindow(WindowDesc *desc, TileArea ta, StationPickerCmdProc&& proc) :
                Window(desc),
                select_station_proc(std::move(proc)),
                area(ta)
        {
                this->CreateNestedTree();
                this->vscroll = this->GetScrollbar(WID_JS_SCROLLBAR);
                this->GetWidget<NWidgetCore>(WID_JS_CAPTION)->widget_data = T::EXPECTED_FACIL == FACIL_WAYPOINT ? STR_JOIN_WAYPOINT_CAPTION : STR_JOIN_STATION_CAPTION;
                this->FinishInitNested(0);
                this->OnInvalidateData(0);

                _thd.freeze = true;
        }

        void Close() override
        {
                if (_settings_client.gui.station_show_coverage) SetViewportCatchmentStation(nullptr, true);

                _thd.freeze = false;
                this->Window::Close();
        }

        void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize) override
        {
                if (widget != WID_JS_PANEL) return;

                /* Determine the widest string */
                Dimension d = GetStringBoundingBox(T::EXPECTED_FACIL == FACIL_WAYPOINT ? STR_JOIN_WAYPOINT_CREATE_SPLITTED_WAYPOINT : STR_JOIN_STATION_CREATE_SPLITTED_STATION);
                for (uint i = 0; i < _stations_nearby_list.size(); i++) {
                        const T *st = T::Get(_stations_nearby_list[i]);
                        SetDParam(0, st->index);
                        SetDParam(1, st->facilities);
                        d = maxdim(d, GetStringBoundingBox(T::EXPECTED_FACIL == FACIL_WAYPOINT ? STR_STATION_LIST_WAYPOINT : STR_STATION_LIST_STATION));
                }

                resize->height = d.height;
                d.height *= 5;
                d.width += WD_FRAMERECT_RIGHT + WD_FRAMERECT_LEFT;
                d.height += WD_FRAMERECT_TOP + WD_FRAMERECT_BOTTOM;
                *size = d;
        }

        void DrawWidget(const Rect &r, int widget) const override
        {
                if (widget != WID_JS_PANEL) return;

                uint y = r.top + WD_FRAMERECT_TOP;
                if (this->vscroll->GetPosition() == 0) {
                        DrawString(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, y, T::EXPECTED_FACIL == FACIL_WAYPOINT ? STR_JOIN_WAYPOINT_CREATE_SPLITTED_WAYPOINT : STR_JOIN_STATION_CREATE_SPLITTED_STATION);
                        y += this->resize.step_height;
                }

                for (uint i = std::max<uint>(1, this->vscroll->GetPosition()); i <= _stations_nearby_list.size(); ++i, y += this->resize.step_height) {
                        /* Don't draw anything if it extends past the end of the window. */
                        if (i - this->vscroll->GetPosition() >= this->vscroll->GetCapacity()) break;

                        const T *st = T::Get(_stations_nearby_list[i - 1]);
                        SetDParam(0, st->index);
                        SetDParam(1, st->facilities);
                        DrawString(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, y, T::EXPECTED_FACIL == FACIL_WAYPOINT ? STR_STATION_LIST_WAYPOINT : STR_STATION_LIST_STATION);
                }
        }

        void OnClick(Point pt, int widget, int click_count) override
        {
                if (widget != WID_JS_PANEL) return;

                uint st_index = this->vscroll->GetScrolledRowFromWidget(pt.y, this, WID_JS_PANEL, WD_FRAMERECT_TOP);
                bool distant_join = (st_index > 0);
                if (distant_join) st_index--;

                if (distant_join && st_index >= _stations_nearby_list.size()) return;

                /* Execute stored Command */
                this->select_station_proc(false, distant_join ? _stations_nearby_list[st_index] : NEW_STATION);

                /* Close Window; this might cause double frees! */
                CloseWindowById(WC_SELECT_STATION, 0);
        }

        void OnRealtimeTick(uint delta_ms) override
        {
                if (_thd.dirty & 2) {
                        _thd.dirty &= ~2;
                        this->SetDirty();
                }
        }

        void OnResize() override
        {
                this->vscroll->SetCapacityFromWidget(this, WID_JS_PANEL, WD_FRAMERECT_TOP + WD_FRAMERECT_BOTTOM);
        }

        /**
         * Some data on this window has become invalid.
         * @param data Information about the changed data.
         * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
         */
        void OnInvalidateData(int data = 0, bool gui_scope = true) override
        {
                if (!gui_scope) return;
                FindStationsNearby<T>(this->area, true);
                this->vscroll->SetCount((uint)_stations_nearby_list.size() + 1);
                this->SetDirty();
        }

        void OnMouseOver(Point pt, int widget) override
        {
                if (widget != WID_JS_PANEL || T::EXPECTED_FACIL == FACIL_WAYPOINT) {
                        SetViewportCatchmentStation(nullptr, true);
                        return;
                }

                /* Show coverage area of station under cursor */
                uint st_index = this->vscroll->GetScrolledRowFromWidget(pt.y, this, WID_JS_PANEL, WD_FRAMERECT_TOP);
                if (st_index == 0 || st_index > _stations_nearby_list.size()) {
                        SetViewportCatchmentStation(nullptr, true);
                } else {
                        st_index--;
                        SetViewportCatchmentStation(Station::Get(_stations_nearby_list[st_index]), true);
                }
        }
};

static WindowDesc _select_station_desc(
        WDP_AUTO, "build_station_join", 200, 180,
        WC_SELECT_STATION, WC_NONE,
        WDF_CONSTRUCTION,
        _nested_select_station_widgets, lengthof(_nested_select_station_widgets)
);


/**
 * Check whether we need to show the station selection window.
 * @param cmd Command to build the station.
 * @param ta Tile area of the to-be-built station
 * @tparam T the type of station
 * @return whether we need to show the station selection window.
 */
template <class T>
static bool StationJoinerNeeded(TileArea ta, const StationPickerCmdProc &proc)
{
        /* Only show selection if distant join is enabled in the settings */
        if (!_settings_game.station.distant_join_stations) return false;

        /* If a window is already opened and we didn't ctrl-click,
         * return true (i.e. just flash the old window) */
        Window *selection_window = FindWindowById(WC_SELECT_STATION, 0);
        if (selection_window != nullptr) {
                /* Abort current distant-join and start new one */
                selection_window->Close();
                UpdateTileSelection();
        }

        /* only show the popup, if we press ctrl */
        if (!_ctrl_pressed) return false;

        /* Now check if we could build there */
        if (!proc(true, INVALID_STATION)) return false;

        /* Test for adjacent station or station below selection.
         * If adjacent-stations is disabled and we are building next to a station, do not show the selection window.
         * but join the other station immediately. */
        const T *st = FindStationsNearby<T>(ta, false);
        return st == nullptr && (_settings_game.station.adjacent_stations || _stations_nearby_list.size() == 0);
}

/**
 * Show the station selection window when needed. If not, build the station.
 * @param cmd Command to build the station.
 * @param ta Area to build the station in
 * @tparam the class to find stations for
 */
template <class T>
void ShowSelectBaseStationIfNeeded(TileArea ta, StationPickerCmdProc&& proc)
{
        if (StationJoinerNeeded<T>(ta, proc)) {
                if (!_settings_client.gui.persistent_buildingtools) ResetObjectToPlace();
                new SelectStationWindow<T>(&_select_station_desc, ta, std::move(proc));
        } else {
                proc(false, INVALID_STATION);
        }
}

/**
 * Show the station selection window when needed. If not, build the station.
 * @param ta Area to build the station in
 * @param proc Function called to execute the build command.
 */
void ShowSelectStationIfNeeded(TileArea ta, StationPickerCmdProc proc)
{
        ShowSelectBaseStationIfNeeded<Station>(ta, std::move(proc));
}

/**
 * Show the waypoint selection window when needed. If not, build the waypoint.
 * @param ta Area to build the waypoint in
 * @param proc Function called to execute the build command.
 */
void ShowSelectWaypointIfNeeded(TileArea ta, StationPickerCmdProc proc)
{
        ShowSelectBaseStationIfNeeded<Waypoint>(ta, std::move(proc));
}