(svn r28004) -Update from Eints:

[openttd.git] / src / build_vehicle_gui.cpp

/* $Id$ */

/*
 * 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 build_vehicle_gui.cpp GUI for building vehicles. */

#include "stdafx.h"
#include "engine_base.h"
#include "engine_func.h"
#include "station_base.h"
#include "network/network.h"
#include "articulated_vehicles.h"
#include "textbuf_gui.h"
#include "command_func.h"
#include "company_func.h"
#include "vehicle_gui.h"
#include "newgrf_engine.h"
#include "newgrf_text.h"
#include "group.h"
#include "string_func.h"
#include "strings_func.h"
#include "window_func.h"
#include "date_func.h"
#include "vehicle_func.h"
#include "widgets/dropdown_func.h"
#include "engine_gui.h"
#include "cargotype.h"
#include "core/geometry_func.hpp"
#include "autoreplace_func.h"

#include "widgets/build_vehicle_widget.h"

#include "table/strings.h"

#include "safeguards.h"

/**
 * Get the height of a single 'entry' in the engine lists.
 * @param type the vehicle type to get the height of
 * @return the height for the entry
 */
uint GetEngineListHeight(VehicleType type)
{
        return max<uint>(FONT_HEIGHT_NORMAL + WD_MATRIX_TOP + WD_MATRIX_BOTTOM, GetVehicleImageCellSize(type, EIT_PURCHASE).height);
}

static const NWidgetPart _nested_build_vehicle_widgets[] = {
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_CLOSEBOX, COLOUR_GREY),
                NWidget(WWT_CAPTION, COLOUR_GREY, WID_BV_CAPTION), SetDataTip(STR_WHITE_STRING, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
                NWidget(WWT_SHADEBOX, COLOUR_GREY),
                NWidget(WWT_DEFSIZEBOX, COLOUR_GREY),
                NWidget(WWT_STICKYBOX, COLOUR_GREY),
        EndContainer(),
        NWidget(WWT_PANEL, COLOUR_GREY),
                NWidget(NWID_VERTICAL),
                        NWidget(NWID_HORIZONTAL),
                                NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_BV_SORT_ASCENDING_DESCENDING), SetDataTip(STR_BUTTON_SORT_BY, STR_TOOLTIP_SORT_ORDER),
                                NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_BV_SORT_DROPDOWN), SetResize(1, 0), SetFill(1, 0), SetDataTip(STR_JUST_STRING, STR_TOOLTIP_SORT_CRITERIA),
                        EndContainer(),
                        NWidget(NWID_HORIZONTAL),
                                NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_BV_SHOW_HIDDEN_ENGINES),
                                NWidget(WWT_DROPDOWN, COLOUR_GREY, WID_BV_CARGO_FILTER_DROPDOWN), SetResize(1, 0), SetFill(1, 0), SetDataTip(STR_JUST_STRING, STR_TOOLTIP_FILTER_CRITERIA),
                        EndContainer(),
                EndContainer(),
        EndContainer(),
        /* Vehicle list. */
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_MATRIX, COLOUR_GREY, WID_BV_LIST), SetResize(1, 1), SetFill(1, 0), SetMatrixDataTip(1, 0, STR_NULL), SetScrollbar(WID_BV_SCROLLBAR),
                NWidget(NWID_VSCROLLBAR, COLOUR_GREY, WID_BV_SCROLLBAR),
        EndContainer(),
        /* Panel with details. */
        NWidget(WWT_PANEL, COLOUR_GREY, WID_BV_PANEL), SetMinimalSize(240, 122), SetResize(1, 0), EndContainer(),
        /* Build/rename buttons, resize button. */
        NWidget(NWID_HORIZONTAL),
                NWidget(NWID_SELECTION, INVALID_COLOUR, WID_BV_BUILD_SEL),
                        NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_BV_BUILD), SetResize(1, 0), SetFill(1, 0),
                EndContainer(),
                NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_BV_SHOW_HIDE), SetResize(1, 0), SetFill(1, 0), SetDataTip(STR_JUST_STRING, STR_NULL),
                NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_BV_RENAME), SetResize(1, 0), SetFill(1, 0),
                NWidget(WWT_RESIZEBOX, COLOUR_GREY),
        EndContainer(),
};

/** Special cargo filter criteria */
static const CargoID CF_ANY  = CT_NO_REFIT; ///< Show all vehicles independent of carried cargo (i.e. no filtering)
static const CargoID CF_NONE = CT_INVALID;  ///< Show only vehicles which do not carry cargo (e.g. train engines)

bool _engine_sort_direction; ///< \c false = descending, \c true = ascending.
byte _engine_sort_last_criteria[]       = {0, 0, 0, 0};                 ///< Last set sort criteria, for each vehicle type.
bool _engine_sort_last_order[]          = {false, false, false, false}; ///< Last set direction of the sort order, for each vehicle type.
bool _engine_sort_show_hidden_engines[] = {false, false, false, false}; ///< Last set 'show hidden engines' setting for each vehicle type.
static CargoID _engine_sort_last_cargo_criteria[] = {CF_ANY, CF_ANY, CF_ANY, CF_ANY}; ///< Last set filter criteria, for each vehicle type.

/**
 * Determines order of engines by engineID
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL EngineNumberSorter(const EngineID *a, const EngineID *b)
{
        int r = Engine::Get(*a)->list_position - Engine::Get(*b)->list_position;

        return _engine_sort_direction ? -r : r;
}

/**
 * Determines order of engines by introduction date
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL EngineIntroDateSorter(const EngineID *a, const EngineID *b)
{
        const int va = Engine::Get(*a)->intro_date;
        const int vb = Engine::Get(*b)->intro_date;
        const int r = va - vb;

        /* Use EngineID to sort instead since we want consistent sorting */
        if (r == 0) return EngineNumberSorter(a, b);
        return _engine_sort_direction ? -r : r;
}

/**
 * Determines order of engines by name
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL EngineNameSorter(const EngineID *a, const EngineID *b)
{
        static EngineID last_engine[2] = { INVALID_ENGINE, INVALID_ENGINE };
        static char     last_name[2][64] = { "\0", "\0" };

        const EngineID va = *a;
        const EngineID vb = *b;

        if (va != last_engine[0]) {
                last_engine[0] = va;
                SetDParam(0, va);
                GetString(last_name[0], STR_ENGINE_NAME, lastof(last_name[0]));
        }

        if (vb != last_engine[1]) {
                last_engine[1] = vb;
                SetDParam(0, vb);
                GetString(last_name[1], STR_ENGINE_NAME, lastof(last_name[1]));
        }

        int r = strnatcmp(last_name[0], last_name[1]); // Sort by name (natural sorting).

        /* Use EngineID to sort instead since we want consistent sorting */
        if (r == 0) return EngineNumberSorter(a, b);
        return _engine_sort_direction ? -r : r;
}

/**
 * Determines order of engines by reliability
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL EngineReliabilitySorter(const EngineID *a, const EngineID *b)
{
        const int va = Engine::Get(*a)->reliability;
        const int vb = Engine::Get(*b)->reliability;
        const int r = va - vb;

        /* Use EngineID to sort instead since we want consistent sorting */
        if (r == 0) return EngineNumberSorter(a, b);
        return _engine_sort_direction ? -r : r;
}

/**
 * Determines order of engines by purchase cost
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL EngineCostSorter(const EngineID *a, const EngineID *b)
{
        Money va = Engine::Get(*a)->GetCost();
        Money vb = Engine::Get(*b)->GetCost();
        int r = ClampToI32(va - vb);

        /* Use EngineID to sort instead since we want consistent sorting */
        if (r == 0) return EngineNumberSorter(a, b);
        return _engine_sort_direction ? -r : r;
}

/**
 * Determines order of engines by speed
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL EngineSpeedSorter(const EngineID *a, const EngineID *b)
{
        int va = Engine::Get(*a)->GetDisplayMaxSpeed();
        int vb = Engine::Get(*b)->GetDisplayMaxSpeed();
        int r = va - vb;

        /* Use EngineID to sort instead since we want consistent sorting */
        if (r == 0) return EngineNumberSorter(a, b);
        return _engine_sort_direction ? -r : r;
}

/**
 * Determines order of engines by power
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL EnginePowerSorter(const EngineID *a, const EngineID *b)
{
        int va = Engine::Get(*a)->GetPower();
        int vb = Engine::Get(*b)->GetPower();
        int r = va - vb;

        /* Use EngineID to sort instead since we want consistent sorting */
        if (r == 0) return EngineNumberSorter(a, b);
        return _engine_sort_direction ? -r : r;
}

/**
 * Determines order of engines by tractive effort
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL EngineTractiveEffortSorter(const EngineID *a, const EngineID *b)
{
        int va = Engine::Get(*a)->GetDisplayMaxTractiveEffort();
        int vb = Engine::Get(*b)->GetDisplayMaxTractiveEffort();
        int r = va - vb;

        /* Use EngineID to sort instead since we want consistent sorting */
        if (r == 0) return EngineNumberSorter(a, b);
        return _engine_sort_direction ? -r : r;
}

/**
 * Determines order of engines by running costs
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL EngineRunningCostSorter(const EngineID *a, const EngineID *b)
{
        Money va = Engine::Get(*a)->GetRunningCost();
        Money vb = Engine::Get(*b)->GetRunningCost();
        int r = ClampToI32(va - vb);

        /* Use EngineID to sort instead since we want consistent sorting */
        if (r == 0) return EngineNumberSorter(a, b);
        return _engine_sort_direction ? -r : r;
}

/**
 * Determines order of engines by running costs
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL EnginePowerVsRunningCostSorter(const EngineID *a, const EngineID *b)
{
        const Engine *e_a = Engine::Get(*a);
        const Engine *e_b = Engine::Get(*b);

        /* Here we are using a few tricks to get the right sort.
         * We want power/running cost, but since we usually got higher running cost than power and we store the result in an int,
         * we will actually calculate cunning cost/power (to make it more than 1).
         * Because of this, the return value have to be reversed as well and we return b - a instead of a - b.
         * Another thing is that both power and running costs should be doubled for multiheaded engines.
         * Since it would be multiplying with 2 in both numerator and denominator, it will even themselves out and we skip checking for multiheaded. */
        Money va = (e_a->GetRunningCost()) / max(1U, (uint)e_a->GetPower());
        Money vb = (e_b->GetRunningCost()) / max(1U, (uint)e_b->GetPower());
        int r = ClampToI32(vb - va);

        /* Use EngineID to sort instead since we want consistent sorting */
        if (r == 0) return EngineNumberSorter(a, b);
        return _engine_sort_direction ? -r : r;
}

/* Train sorting functions */

/**
 * Determines order of train engines by capacity
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL TrainEngineCapacitySorter(const EngineID *a, const EngineID *b)
{
        const RailVehicleInfo *rvi_a = RailVehInfo(*a);
        const RailVehicleInfo *rvi_b = RailVehInfo(*b);

        int va = GetTotalCapacityOfArticulatedParts(*a) * (rvi_a->railveh_type == RAILVEH_MULTIHEAD ? 2 : 1);
        int vb = GetTotalCapacityOfArticulatedParts(*b) * (rvi_b->railveh_type == RAILVEH_MULTIHEAD ? 2 : 1);
        int r = va - vb;

        /* Use EngineID to sort instead since we want consistent sorting */
        if (r == 0) return EngineNumberSorter(a, b);
        return _engine_sort_direction ? -r : r;
}

/**
 * Determines order of train engines by engine / wagon
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL TrainEnginesThenWagonsSorter(const EngineID *a, const EngineID *b)
{
        int val_a = (RailVehInfo(*a)->railveh_type == RAILVEH_WAGON ? 1 : 0);
        int val_b = (RailVehInfo(*b)->railveh_type == RAILVEH_WAGON ? 1 : 0);
        int r = val_a - val_b;

        /* Use EngineID to sort instead since we want consistent sorting */
        if (r == 0) return EngineNumberSorter(a, b);
        return _engine_sort_direction ? -r : r;
}

/* Road vehicle sorting functions */

/**
 * Determines order of road vehicles by capacity
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL RoadVehEngineCapacitySorter(const EngineID *a, const EngineID *b)
{
        int va = GetTotalCapacityOfArticulatedParts(*a);
        int vb = GetTotalCapacityOfArticulatedParts(*b);
        int r = va - vb;

        /* Use EngineID to sort instead since we want consistent sorting */
        if (r == 0) return EngineNumberSorter(a, b);
        return _engine_sort_direction ? -r : r;
}

/* Ship vehicle sorting functions */

/**
 * Determines order of ships by capacity
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL ShipEngineCapacitySorter(const EngineID *a, const EngineID *b)
{
        const Engine *e_a = Engine::Get(*a);
        const Engine *e_b = Engine::Get(*b);

        int va = e_a->GetDisplayDefaultCapacity();
        int vb = e_b->GetDisplayDefaultCapacity();
        int r = va - vb;

        /* Use EngineID to sort instead since we want consistent sorting */
        if (r == 0) return EngineNumberSorter(a, b);
        return _engine_sort_direction ? -r : r;
}

/* Aircraft sorting functions */

/**
 * Determines order of aircraft by cargo
 * @param *a first engine to compare
 * @param *b second engine to compare
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal
 */
static int CDECL AircraftEngineCargoSorter(const EngineID *a, const EngineID *b)
{
        const Engine *e_a = Engine::Get(*a);
        const Engine *e_b = Engine::Get(*b);

        uint16 mail_a, mail_b;
        int va = e_a->GetDisplayDefaultCapacity(&mail_a);
        int vb = e_b->GetDisplayDefaultCapacity(&mail_b);
        int r = va - vb;

        if (r == 0) {
                /* The planes have the same passenger capacity. Check mail capacity instead */
                r = mail_a - mail_b;

                if (r == 0) {
                        /* Use EngineID to sort instead since we want consistent sorting */
                        return EngineNumberSorter(a, b);
                }
        }
        return _engine_sort_direction ? -r : r;
}

/**
 * Determines order of aircraft by range.
 * @param *a first engine to compare.
 * @param *b second engine to compare.
 * @return for descending order: returns < 0 if a < b and > 0 for a > b. Vice versa for ascending order and 0 for equal.
 */
static int CDECL AircraftRangeSorter(const EngineID *a, const EngineID *b)
{
        uint16 r_a = Engine::Get(*a)->GetRange();
        uint16 r_b = Engine::Get(*b)->GetRange();

        int r = r_a - r_b;

        /* Use EngineID to sort instead since we want consistent sorting */
        if (r == 0) return EngineNumberSorter(a, b);
        return _engine_sort_direction ? -r : r;
}

/** Sort functions for the vehicle sort criteria, for each vehicle type. */
EngList_SortTypeFunction * const _engine_sort_functions[][11] = {{
        /* Trains */
        &EngineNumberSorter,
        &EngineCostSorter,
        &EngineSpeedSorter,
        &EnginePowerSorter,
        &EngineTractiveEffortSorter,
        &EngineIntroDateSorter,
        &EngineNameSorter,
        &EngineRunningCostSorter,
        &EnginePowerVsRunningCostSorter,
        &EngineReliabilitySorter,
        &TrainEngineCapacitySorter,
}, {
        /* Road vehicles */
        &EngineNumberSorter,
        &EngineCostSorter,
        &EngineSpeedSorter,
        &EnginePowerSorter,
        &EngineTractiveEffortSorter,
        &EngineIntroDateSorter,
        &EngineNameSorter,
        &EngineRunningCostSorter,
        &EnginePowerVsRunningCostSorter,
        &EngineReliabilitySorter,
        &RoadVehEngineCapacitySorter,
}, {
        /* Ships */
        &EngineNumberSorter,
        &EngineCostSorter,
        &EngineSpeedSorter,
        &EngineIntroDateSorter,
        &EngineNameSorter,
        &EngineRunningCostSorter,
        &EngineReliabilitySorter,
        &ShipEngineCapacitySorter,
}, {
        /* Aircraft */
        &EngineNumberSorter,
        &EngineCostSorter,
        &EngineSpeedSorter,
        &EngineIntroDateSorter,
        &EngineNameSorter,
        &EngineRunningCostSorter,
        &EngineReliabilitySorter,
        &AircraftEngineCargoSorter,
        &AircraftRangeSorter,
}};

/** Dropdown menu strings for the vehicle sort criteria. */
const StringID _engine_sort_listing[][12] = {{
        /* Trains */
        STR_SORT_BY_ENGINE_ID,
        STR_SORT_BY_COST,
        STR_SORT_BY_MAX_SPEED,
        STR_SORT_BY_POWER,
        STR_SORT_BY_TRACTIVE_EFFORT,
        STR_SORT_BY_INTRO_DATE,
        STR_SORT_BY_NAME,
        STR_SORT_BY_RUNNING_COST,
        STR_SORT_BY_POWER_VS_RUNNING_COST,
        STR_SORT_BY_RELIABILITY,
        STR_SORT_BY_CARGO_CAPACITY,
        INVALID_STRING_ID
}, {
        /* Road vehicles */
        STR_SORT_BY_ENGINE_ID,
        STR_SORT_BY_COST,
        STR_SORT_BY_MAX_SPEED,
        STR_SORT_BY_POWER,
        STR_SORT_BY_TRACTIVE_EFFORT,
        STR_SORT_BY_INTRO_DATE,
        STR_SORT_BY_NAME,
        STR_SORT_BY_RUNNING_COST,
        STR_SORT_BY_POWER_VS_RUNNING_COST,
        STR_SORT_BY_RELIABILITY,
        STR_SORT_BY_CARGO_CAPACITY,
        INVALID_STRING_ID
}, {
        /* Ships */
        STR_SORT_BY_ENGINE_ID,
        STR_SORT_BY_COST,
        STR_SORT_BY_MAX_SPEED,
        STR_SORT_BY_INTRO_DATE,
        STR_SORT_BY_NAME,
        STR_SORT_BY_RUNNING_COST,
        STR_SORT_BY_RELIABILITY,
        STR_SORT_BY_CARGO_CAPACITY,
        INVALID_STRING_ID
}, {
        /* Aircraft */
        STR_SORT_BY_ENGINE_ID,
        STR_SORT_BY_COST,
        STR_SORT_BY_MAX_SPEED,
        STR_SORT_BY_INTRO_DATE,
        STR_SORT_BY_NAME,
        STR_SORT_BY_RUNNING_COST,
        STR_SORT_BY_RELIABILITY,
        STR_SORT_BY_CARGO_CAPACITY,
        STR_SORT_BY_RANGE,
        INVALID_STRING_ID
}};

/** Cargo filter functions */
static bool CDECL CargoFilter(const EngineID *eid, const CargoID cid)
{
        if (cid == CF_ANY) return true;
        uint32 refit_mask = GetUnionOfArticulatedRefitMasks(*eid, true) & _standard_cargo_mask;
        return (cid == CF_NONE ? refit_mask == 0 : HasBit(refit_mask, cid));
}

static GUIEngineList::FilterFunction * const _filter_funcs[] = {
        &CargoFilter,
};

static int DrawCargoCapacityInfo(int left, int right, int y, EngineID engine)
{
        CargoArray cap;
        uint32 refits;
        GetArticulatedVehicleCargoesAndRefits(engine, &cap, &refits);

        for (CargoID c = 0; c < NUM_CARGO; c++) {
                if (cap[c] == 0) continue;

                SetDParam(0, c);
                SetDParam(1, cap[c]);
                SetDParam(2, HasBit(refits, c) ? STR_PURCHASE_INFO_REFITTABLE : STR_EMPTY);
                DrawString(left, right, y, STR_PURCHASE_INFO_CAPACITY);
                y += FONT_HEIGHT_NORMAL;
        }

        return y;
}

/* Draw rail wagon specific details */
static int DrawRailWagonPurchaseInfo(int left, int right, int y, EngineID engine_number, const RailVehicleInfo *rvi)
{
        const Engine *e = Engine::Get(engine_number);

        /* Purchase cost */
        SetDParam(0, e->GetCost());
        DrawString(left, right, y, STR_PURCHASE_INFO_COST);
        y += FONT_HEIGHT_NORMAL;

        /* Wagon weight - (including cargo) */
        uint weight = e->GetDisplayWeight();
        SetDParam(0, weight);
        uint cargo_weight = (e->CanCarryCargo() ? CargoSpec::Get(e->GetDefaultCargoType())->weight * GetTotalCapacityOfArticulatedParts(engine_number) / 16 : 0);
        SetDParam(1, cargo_weight + weight);
        DrawString(left, right, y, STR_PURCHASE_INFO_WEIGHT_CWEIGHT);
        y += FONT_HEIGHT_NORMAL;

        /* Wagon speed limit, displayed if above zero */
        if (_settings_game.vehicle.wagon_speed_limits) {
                uint max_speed = e->GetDisplayMaxSpeed();
                if (max_speed > 0) {
                        SetDParam(0, max_speed);
                        DrawString(left, right, y, STR_PURCHASE_INFO_SPEED);
                        y += FONT_HEIGHT_NORMAL;
                }
        }

        /* Running cost */
        if (rvi->running_cost_class != INVALID_PRICE) {
                SetDParam(0, e->GetRunningCost());
                DrawString(left, right, y, STR_PURCHASE_INFO_RUNNINGCOST);
                y += FONT_HEIGHT_NORMAL;
        }

        return y;
}

/* Draw locomotive specific details */
static int DrawRailEnginePurchaseInfo(int left, int right, int y, EngineID engine_number, const RailVehicleInfo *rvi)
{
        const Engine *e = Engine::Get(engine_number);

        /* Purchase Cost - Engine weight */
        SetDParam(0, e->GetCost());
        SetDParam(1, e->GetDisplayWeight());
        DrawString(left, right, y, STR_PURCHASE_INFO_COST_WEIGHT);
        y += FONT_HEIGHT_NORMAL;

        /* Max speed - Engine power */
        SetDParam(0, e->GetDisplayMaxSpeed());
        SetDParam(1, e->GetPower());
        DrawString(left, right, y, STR_PURCHASE_INFO_SPEED_POWER);
        y += FONT_HEIGHT_NORMAL;

        /* Max tractive effort - not applicable if old acceleration or maglev */
        if (_settings_game.vehicle.train_acceleration_model != AM_ORIGINAL && GetRailTypeInfo(rvi->railtype)->acceleration_type != 2) {
                SetDParam(0, e->GetDisplayMaxTractiveEffort());
                DrawString(left, right, y, STR_PURCHASE_INFO_MAX_TE);
                y += FONT_HEIGHT_NORMAL;
        }

        /* Running cost */
        if (rvi->running_cost_class != INVALID_PRICE) {
                SetDParam(0, e->GetRunningCost());
                DrawString(left, right, y, STR_PURCHASE_INFO_RUNNINGCOST);
                y += FONT_HEIGHT_NORMAL;
        }

        /* Powered wagons power - Powered wagons extra weight */
        if (rvi->pow_wag_power != 0) {
                SetDParam(0, rvi->pow_wag_power);
                SetDParam(1, rvi->pow_wag_weight);
                DrawString(left, right, y, STR_PURCHASE_INFO_PWAGPOWER_PWAGWEIGHT);
                y += FONT_HEIGHT_NORMAL;
        }

        return y;
}

/* Draw road vehicle specific details */
static int DrawRoadVehPurchaseInfo(int left, int right, int y, EngineID engine_number)
{
        const Engine *e = Engine::Get(engine_number);

        if (_settings_game.vehicle.roadveh_acceleration_model != AM_ORIGINAL) {
                /* Purchase Cost */
                SetDParam(0, e->GetCost());
                DrawString(left, right, y, STR_PURCHASE_INFO_COST);
                y += FONT_HEIGHT_NORMAL;

                /* Road vehicle weight - (including cargo) */
                int16 weight = e->GetDisplayWeight();
                SetDParam(0, weight);
                uint cargo_weight = (e->CanCarryCargo() ? CargoSpec::Get(e->GetDefaultCargoType())->weight * GetTotalCapacityOfArticulatedParts(engine_number) / 16 : 0);
                SetDParam(1, cargo_weight + weight);
                DrawString(left, right, y, STR_PURCHASE_INFO_WEIGHT_CWEIGHT);
                y += FONT_HEIGHT_NORMAL;

                /* Max speed - Engine power */
                SetDParam(0, e->GetDisplayMaxSpeed());
                SetDParam(1, e->GetPower());
                DrawString(left, right, y, STR_PURCHASE_INFO_SPEED_POWER);
                y += FONT_HEIGHT_NORMAL;

                /* Max tractive effort */
                SetDParam(0, e->GetDisplayMaxTractiveEffort());
                DrawString(left, right, y, STR_PURCHASE_INFO_MAX_TE);
                y += FONT_HEIGHT_NORMAL;
        } else {
                /* Purchase cost - Max speed */
                SetDParam(0, e->GetCost());
                SetDParam(1, e->GetDisplayMaxSpeed());
                DrawString(left, right, y, STR_PURCHASE_INFO_COST_SPEED);
                y += FONT_HEIGHT_NORMAL;
        }

        /* Running cost */
        SetDParam(0, e->GetRunningCost());
        DrawString(left, right, y, STR_PURCHASE_INFO_RUNNINGCOST);
        y += FONT_HEIGHT_NORMAL;

        return y;
}

/* Draw ship specific details */
static int DrawShipPurchaseInfo(int left, int right, int y, EngineID engine_number, bool refittable)
{
        const Engine *e = Engine::Get(engine_number);

        /* Purchase cost - Max speed */
        uint raw_speed = e->GetDisplayMaxSpeed();
        uint ocean_speed = e->u.ship.ApplyWaterClassSpeedFrac(raw_speed, true);
        uint canal_speed = e->u.ship.ApplyWaterClassSpeedFrac(raw_speed, false);

        SetDParam(0, e->GetCost());
        if (ocean_speed == canal_speed) {
                SetDParam(1, ocean_speed);
                DrawString(left, right, y, STR_PURCHASE_INFO_COST_SPEED);
                y += FONT_HEIGHT_NORMAL;
        } else {
                DrawString(left, right, y, STR_PURCHASE_INFO_COST);
                y += FONT_HEIGHT_NORMAL;

                SetDParam(0, ocean_speed);
                DrawString(left, right, y, STR_PURCHASE_INFO_SPEED_OCEAN);
                y += FONT_HEIGHT_NORMAL;

                SetDParam(0, canal_speed);
                DrawString(left, right, y, STR_PURCHASE_INFO_SPEED_CANAL);
                y += FONT_HEIGHT_NORMAL;
        }

        /* Cargo type + capacity */
        SetDParam(0, e->GetDefaultCargoType());
        SetDParam(1, e->GetDisplayDefaultCapacity());
        SetDParam(2, refittable ? STR_PURCHASE_INFO_REFITTABLE : STR_EMPTY);
        DrawString(left, right, y, STR_PURCHASE_INFO_CAPACITY);
        y += FONT_HEIGHT_NORMAL;

        /* Running cost */
        SetDParam(0, e->GetRunningCost());
        DrawString(left, right, y, STR_PURCHASE_INFO_RUNNINGCOST);
        y += FONT_HEIGHT_NORMAL;

        return y;
}

/**
 * Draw aircraft specific details in the buy window.
 * @param left Left edge of the window to draw in.
 * @param right Right edge of the window to draw in.
 * @param y Top of the area to draw in.
 * @param engine_number Engine to display.
 * @param refittable If set, the aircraft can be refitted.
 * @return Bottom of the used area.
 */
static int DrawAircraftPurchaseInfo(int left, int right, int y, EngineID engine_number, bool refittable)
{
        const Engine *e = Engine::Get(engine_number);
        CargoID cargo = e->GetDefaultCargoType();

        /* Purchase cost - Max speed */
        SetDParam(0, e->GetCost());
        SetDParam(1, e->GetDisplayMaxSpeed());
        DrawString(left, right, y, STR_PURCHASE_INFO_COST_SPEED);
        y += FONT_HEIGHT_NORMAL;

        /* Cargo capacity */
        uint16 mail_capacity;
        uint capacity = e->GetDisplayDefaultCapacity(&mail_capacity);
        if (mail_capacity > 0) {
                SetDParam(0, cargo);
                SetDParam(1, capacity);
                SetDParam(2, CT_MAIL);
                SetDParam(3, mail_capacity);
                DrawString(left, right, y, STR_PURCHASE_INFO_AIRCRAFT_CAPACITY);
        } else {
                /* Note, if the default capacity is selected by the refit capacity
                 * callback, then the capacity shown is likely to be incorrect. */
                SetDParam(0, cargo);
                SetDParam(1, capacity);
                SetDParam(2, refittable ? STR_PURCHASE_INFO_REFITTABLE : STR_EMPTY);
                DrawString(left, right, y, STR_PURCHASE_INFO_CAPACITY);
        }
        y += FONT_HEIGHT_NORMAL;

        /* Running cost */
        SetDParam(0, e->GetRunningCost());
        DrawString(left, right, y, STR_PURCHASE_INFO_RUNNINGCOST);
        y += FONT_HEIGHT_NORMAL;

        /* Aircraft type */
        SetDParam(0, e->GetAircraftTypeText());
        DrawString(left, right, y, STR_PURCHASE_INFO_AIRCRAFT_TYPE);
        y += FONT_HEIGHT_NORMAL;

        /* Aircraft range, if available. */
        uint16 range = e->GetRange();
        if (range != 0) {
                SetDParam(0, range);
                DrawString(left, right, y, STR_PURCHASE_INFO_AIRCRAFT_RANGE);
                y += FONT_HEIGHT_NORMAL;
        }

        return y;
}

/**
 * Display additional text from NewGRF in the purchase information window
 * @param left   Left border of text bounding box
 * @param right  Right border of text bounding box
 * @param y      Top border of text bounding box
 * @param engine Engine to query the additional purchase information for
 * @return       Bottom border of text bounding box
 */
static uint ShowAdditionalText(int left, int right, int y, EngineID engine)
{
        uint16 callback = GetVehicleCallback(CBID_VEHICLE_ADDITIONAL_TEXT, 0, 0, engine, NULL);
        if (callback == CALLBACK_FAILED || callback == 0x400) return y;
        const GRFFile *grffile = Engine::Get(engine)->GetGRF();
        if (callback > 0x400) {
                ErrorUnknownCallbackResult(grffile->grfid, CBID_VEHICLE_ADDITIONAL_TEXT, callback);
                return y;
        }

        StartTextRefStackUsage(grffile, 6);
        uint result = DrawStringMultiLine(left, right, y, INT32_MAX, GetGRFStringID(grffile->grfid, 0xD000 + callback), TC_BLACK);
        StopTextRefStackUsage();
        return result;
}

/**
 * Draw the purchase info details of a vehicle at a given location.
 * @param left,right,y location where to draw the info
 * @param engine_number the engine of which to draw the info of
 * @return y after drawing all the text
 */
int DrawVehiclePurchaseInfo(int left, int right, int y, EngineID engine_number)
{
        const Engine *e = Engine::Get(engine_number);
        YearMonthDay ymd;
        ConvertDateToYMD(e->intro_date, &ymd);
        bool refittable = IsArticulatedVehicleRefittable(engine_number);
        bool articulated_cargo = false;

        switch (e->type) {
                default: NOT_REACHED();
                case VEH_TRAIN:
                        if (e->u.rail.railveh_type == RAILVEH_WAGON) {
                                y = DrawRailWagonPurchaseInfo(left, right, y, engine_number, &e->u.rail);
                        } else {
                                y = DrawRailEnginePurchaseInfo(left, right, y, engine_number, &e->u.rail);
                        }
                        articulated_cargo = true;
                        break;

                case VEH_ROAD:
                        y = DrawRoadVehPurchaseInfo(left, right, y, engine_number);
                        articulated_cargo = true;
                        break;

                case VEH_SHIP:
                        y = DrawShipPurchaseInfo(left, right, y, engine_number, refittable);
                        break;

                case VEH_AIRCRAFT:
                        y = DrawAircraftPurchaseInfo(left, right, y, engine_number, refittable);
                        break;
        }

        if (articulated_cargo) {
                /* Cargo type + capacity, or N/A */
                int new_y = DrawCargoCapacityInfo(left, right, y, engine_number);

                if (new_y == y) {
                        SetDParam(0, CT_INVALID);
                        SetDParam(2, STR_EMPTY);
                        DrawString(left, right, y, STR_PURCHASE_INFO_CAPACITY);
                        y += FONT_HEIGHT_NORMAL;
                } else {
                        y = new_y;
                }
        }

        /* Draw details that apply to all types except rail wagons. */
        if (e->type != VEH_TRAIN || e->u.rail.railveh_type != RAILVEH_WAGON) {
                /* Design date - Life length */
                SetDParam(0, ymd.year);
                SetDParam(1, e->GetLifeLengthInDays() / DAYS_IN_LEAP_YEAR);
                DrawString(left, right, y, STR_PURCHASE_INFO_DESIGNED_LIFE);
                y += FONT_HEIGHT_NORMAL;

                /* Reliability */
                SetDParam(0, ToPercent16(e->reliability));
                DrawString(left, right, y, STR_PURCHASE_INFO_RELIABILITY);
                y += FONT_HEIGHT_NORMAL;
        }

        if (refittable) y = ShowRefitOptionsList(left, right, y, engine_number);

        /* Additional text from NewGRF */
        y = ShowAdditionalText(left, right, y, engine_number);

        return y;
}

/**
 * Engine drawing loop
 * @param type Type of vehicle (VEH_*)
 * @param l The left most location of the list
 * @param r The right most location of the list
 * @param y The top most location of the list
 * @param eng_list What engines to draw
 * @param min where to start in the list
 * @param max where in the list to end
 * @param selected_id what engine to highlight as selected, if any
 * @param show_count Whether to show the amount of engines or not
 * @param selected_group the group to list the engines of
 */
void DrawEngineList(VehicleType type, int l, int r, int y, const GUIEngineList *eng_list, uint16 min, uint16 max, EngineID selected_id, bool show_count, GroupID selected_group)
{
        static const int sprite_y_offsets[] = { -1, -1, -2, -2 };

        /* Obligatory sanity checks! */
        assert(max <= eng_list->Length());

        bool rtl = _current_text_dir == TD_RTL;
        int step_size = GetEngineListHeight(type);
        int sprite_left  = GetVehicleImageCellSize(type, EIT_PURCHASE).extend_left;
        int sprite_right = GetVehicleImageCellSize(type, EIT_PURCHASE).extend_right;
        int sprite_width = sprite_left + sprite_right;

        int sprite_x        = rtl ? r - sprite_right - 1 : l + sprite_left + 1;
        int sprite_y_offset = sprite_y_offsets[type] + step_size / 2;

        Dimension replace_icon = {0, 0};
        int count_width = 0;
        if (show_count) {
                replace_icon = GetSpriteSize(SPR_GROUP_REPLACE_ACTIVE);
                SetDParamMaxDigits(0, 3, FS_SMALL);
                count_width = GetStringBoundingBox(STR_TINY_BLACK_COMA).width;
        }

        int text_left  = l + (rtl ? WD_FRAMERECT_LEFT + replace_icon.width + 8 + count_width : sprite_width + WD_FRAMETEXT_LEFT);
        int text_right = r - (rtl ? sprite_width + WD_FRAMETEXT_RIGHT : WD_FRAMERECT_RIGHT + replace_icon.width + 8 + count_width);
        int replace_icon_left = rtl ? l + WD_FRAMERECT_LEFT : r - WD_FRAMERECT_RIGHT - replace_icon.width;
        int count_left = l;
        int count_right = rtl ? text_left : r - WD_FRAMERECT_RIGHT - replace_icon.width - 8;

        int normal_text_y_offset = (step_size - FONT_HEIGHT_NORMAL) / 2;
        int small_text_y_offset  = step_size - FONT_HEIGHT_SMALL - WD_FRAMERECT_BOTTOM - 1;
        int replace_icon_y_offset = (step_size - replace_icon.height) / 2 - 1;

        for (; min < max; min++, y += step_size) {
                const EngineID engine = (*eng_list)[min];
                /* Note: num_engines is only used in the autoreplace GUI, so it is correct to use _local_company here. */
                const uint num_engines = GetGroupNumEngines(_local_company, selected_group, engine);

                const Engine *e = Engine::Get(engine);
                bool hidden = HasBit(e->company_hidden, _local_company);
                StringID str = hidden ? STR_HIDDEN_ENGINE_NAME : STR_ENGINE_NAME;
                TextColour tc = (engine == selected_id) ? TC_WHITE : (TC_NO_SHADE | (hidden ? TC_GREY : TC_BLACK));

                SetDParam(0, engine);
                DrawString(text_left, text_right, y + normal_text_y_offset, str, tc);
                DrawVehicleEngine(l, r, sprite_x, y + sprite_y_offset, engine, (show_count && num_engines == 0) ? PALETTE_CRASH : GetEnginePalette(engine, _local_company), EIT_PURCHASE);
                if (show_count) {
                        SetDParam(0, num_engines);
                        DrawString(count_left, count_right, y + small_text_y_offset, STR_TINY_BLACK_COMA, TC_FROMSTRING, SA_RIGHT | SA_FORCE);
                        if (EngineHasReplacementForCompany(Company::Get(_local_company), engine, selected_group)) DrawSprite(SPR_GROUP_REPLACE_ACTIVE, num_engines == 0 ? PALETTE_CRASH : PAL_NONE, replace_icon_left, y + replace_icon_y_offset);
                }
        }
}

/**
 * Display the dropdown for the vehicle sort criteria.
 * @param w Parent window (holds the dropdown button).
 * @param vehicle_type %Vehicle type being sorted.
 * @param selected Currently selected sort criterium.
 * @param button Widget button.
 */
void DisplayVehicleSortDropDown(Window *w, VehicleType vehicle_type, int selected, int button)
{
        uint32 hidden_mask = 0;
        /* Disable sorting by power or tractive effort when the original acceleration model for road vehicles is being used. */
        if (vehicle_type == VEH_ROAD && _settings_game.vehicle.roadveh_acceleration_model == AM_ORIGINAL) {
                SetBit(hidden_mask, 3); // power
                SetBit(hidden_mask, 4); // tractive effort
                SetBit(hidden_mask, 8); // power by running costs
        }
        /* Disable sorting by tractive effort when the original acceleration model for trains is being used. */
        if (vehicle_type == VEH_TRAIN && _settings_game.vehicle.train_acceleration_model == AM_ORIGINAL) {
                SetBit(hidden_mask, 4); // tractive effort
        }
        ShowDropDownMenu(w, _engine_sort_listing[vehicle_type], selected, button, 0, hidden_mask);
}

/** GUI for building vehicles. */
struct BuildVehicleWindow : Window {
        VehicleType vehicle_type;                   ///< Type of vehicles shown in the window.
        union {
                RailTypeByte railtype;              ///< Rail type to show, or #RAILTYPE_END.
                RoadTypes roadtypes;                ///< Road type to show, or #ROADTYPES_ALL.
        } filter;                                   ///< Filter to apply.
        bool descending_sort_order;                 ///< Sort direction, @see _engine_sort_direction
        byte sort_criteria;                         ///< Current sort criterium.
        bool show_hidden_engines;                   ///< State of the 'show hidden engines' button.
        bool listview_mode;                         ///< If set, only display the available vehicles and do not show a 'build' button.
        EngineID sel_engine;                        ///< Currently selected engine, or #INVALID_ENGINE
        EngineID rename_engine;                     ///< Engine being renamed.
        GUIEngineList eng_list;
        CargoID cargo_filter[NUM_CARGO + 2];        ///< Available cargo filters; CargoID or CF_ANY or CF_NONE
        StringID cargo_filter_texts[NUM_CARGO + 3]; ///< Texts for filter_cargo, terminated by INVALID_STRING_ID
        byte cargo_filter_criteria;                 ///< Selected cargo filter
        int details_height;                         ///< Minimal needed height of the details panels (found so far).
        Scrollbar *vscroll;

        BuildVehicleWindow(WindowDesc *desc, TileIndex tile, VehicleType type) : Window(desc)
        {
                this->vehicle_type = type;
                this->window_number = tile == INVALID_TILE ? (int)type : tile;

                this->sel_engine = INVALID_ENGINE;

                this->sort_criteria         = _engine_sort_last_criteria[type];
                this->descending_sort_order = _engine_sort_last_order[type];
                this->show_hidden_engines   = _engine_sort_show_hidden_engines[type];

                switch (type) {
                        default: NOT_REACHED();
                        case VEH_TRAIN:
                                this->filter.railtype = (tile == INVALID_TILE) ? RAILTYPE_END : GetRailType(tile);
                                break;
                        case VEH_ROAD:
                                this->filter.roadtypes = (tile == INVALID_TILE) ? ROADTYPES_ALL : GetRoadTypes(tile);
                        case VEH_SHIP:
                        case VEH_AIRCRAFT:
                                break;
                }

                this->listview_mode = (this->window_number <= VEH_END);

                this->CreateNestedTree();

                this->vscroll = this->GetScrollbar(WID_BV_SCROLLBAR);

                /* If we are just viewing the list of vehicles, we do not need the Build button.
                 * So we just hide it, and enlarge the Rename button by the now vacant place. */
                if (this->listview_mode) this->GetWidget<NWidgetStacked>(WID_BV_BUILD_SEL)->SetDisplayedPlane(SZSP_NONE);

                /* disable renaming engines in network games if you are not the server */
                this->SetWidgetDisabledState(WID_BV_RENAME, _networking && !_network_server);

                NWidgetCore *widget = this->GetWidget<NWidgetCore>(WID_BV_LIST);
                widget->tool_tip = STR_BUY_VEHICLE_TRAIN_LIST_TOOLTIP + type;

                widget = this->GetWidget<NWidgetCore>(WID_BV_SHOW_HIDE);
                widget->tool_tip = STR_BUY_VEHICLE_TRAIN_HIDE_SHOW_TOGGLE_TOOLTIP + type;

                widget = this->GetWidget<NWidgetCore>(WID_BV_BUILD);
                widget->widget_data = STR_BUY_VEHICLE_TRAIN_BUY_VEHICLE_BUTTON + type;
                widget->tool_tip    = STR_BUY_VEHICLE_TRAIN_BUY_VEHICLE_TOOLTIP + type;

                widget = this->GetWidget<NWidgetCore>(WID_BV_RENAME);
                widget->widget_data = STR_BUY_VEHICLE_TRAIN_RENAME_BUTTON + type;
                widget->tool_tip    = STR_BUY_VEHICLE_TRAIN_RENAME_TOOLTIP + type;

                widget = this->GetWidget<NWidgetCore>(WID_BV_SHOW_HIDDEN_ENGINES);
                widget->widget_data = STR_SHOW_HIDDEN_ENGINES_VEHICLE_TRAIN + type;
                widget->tool_tip    = STR_SHOW_HIDDEN_ENGINES_VEHICLE_TRAIN_TOOLTIP + type;
                widget->SetLowered(this->show_hidden_engines);

                this->details_height = ((this->vehicle_type == VEH_TRAIN) ? 10 : 9) * FONT_HEIGHT_NORMAL + WD_FRAMERECT_TOP + WD_FRAMERECT_BOTTOM;

                this->FinishInitNested(tile == INVALID_TILE ? (int)type : tile);

                this->owner = (tile != INVALID_TILE) ? GetTileOwner(tile) : _local_company;

                this->eng_list.ForceRebuild();
                this->GenerateBuildList(); // generate the list, since we need it in the next line
                /* Select the first engine in the list as default when opening the window */
                if (this->eng_list.Length() > 0) this->sel_engine = this->eng_list[0];
        }

        /** Populate the filter list and set the cargo filter criteria. */
        void SetCargoFilterArray()
        {
                uint filter_items = 0;

                /* Add item for disabling filtering. */
                this->cargo_filter[filter_items] = CF_ANY;
                this->cargo_filter_texts[filter_items] = STR_PURCHASE_INFO_ALL_TYPES;
                filter_items++;

                /* Add item for vehicles not carrying anything, e.g. train engines.
                 * This could also be useful for eyecandy vehicles of other types, but is likely too confusing for joe, */
                if (this->vehicle_type == VEH_TRAIN) {
                        this->cargo_filter[filter_items] = CF_NONE;
                        this->cargo_filter_texts[filter_items] = STR_LAND_AREA_INFORMATION_LOCAL_AUTHORITY_NONE;
                        filter_items++;
                }

                /* Collect available cargo types for filtering. */
                const CargoSpec *cs;
                FOR_ALL_SORTED_STANDARD_CARGOSPECS(cs) {
                        this->cargo_filter[filter_items] = cs->Index();
                        this->cargo_filter_texts[filter_items] = cs->name;
                        filter_items++;
                }

                /* Terminate the filter list. */
                this->cargo_filter_texts[filter_items] = INVALID_STRING_ID;

                /* If not found, the cargo criteria will be set to all cargoes. */
                this->cargo_filter_criteria = 0;

                /* Find the last cargo filter criteria. */
                for (uint i = 0; i < filter_items; i++) {
                        if (this->cargo_filter[i] == _engine_sort_last_cargo_criteria[this->vehicle_type]) {
                                this->cargo_filter_criteria = i;
                                break;
                        }
                }

                this->eng_list.SetFilterFuncs(_filter_funcs);
                this->eng_list.SetFilterState(this->cargo_filter[this->cargo_filter_criteria] != CF_ANY);
        }

        void OnInit()
        {
                this->SetCargoFilterArray();
        }

        /** Filter the engine list against the currently selected cargo filter */
        void FilterEngineList()
        {
                this->eng_list.Filter(this->cargo_filter[this->cargo_filter_criteria]);
                if (0 == this->eng_list.Length()) { // no engine passed through the filter, invalidate the previously selected engine
                        this->sel_engine = INVALID_ENGINE;
                } else if (!this->eng_list.Contains(this->sel_engine)) { // previously selected engine didn't pass the filter, select the first engine of the list
                        this->sel_engine = this->eng_list[0];
                }
        }

        /** Filter a single engine */
        bool FilterSingleEngine(EngineID eid)
        {
                CargoID filter_type = this->cargo_filter[this->cargo_filter_criteria];
                return (filter_type == CF_ANY || CargoFilter(&eid, filter_type));
        }

        /* Figure out what train EngineIDs to put in the list */
        void GenerateBuildTrainList()
        {
                EngineID sel_id = INVALID_ENGINE;
                int num_engines = 0;
                int num_wagons  = 0;

                this->filter.railtype = (this->listview_mode) ? RAILTYPE_END : GetRailType(this->window_number);

                this->eng_list.Clear();

                /* Make list of all available train engines and wagons.
                 * Also check to see if the previously selected engine is still available,
                 * and if not, reset selection to INVALID_ENGINE. This could be the case
                 * when engines become obsolete and are removed */
                const Engine *e;
                FOR_ALL_ENGINES_OF_TYPE(e, VEH_TRAIN) {
                        if (!this->show_hidden_engines && e->IsHidden(_local_company)) continue;
                        EngineID eid = e->index;
                        const RailVehicleInfo *rvi = &e->u.rail;

                        if (this->filter.railtype != RAILTYPE_END && !HasPowerOnRail(rvi->railtype, this->filter.railtype)) continue;
                        if (!IsEngineBuildable(eid, VEH_TRAIN, _local_company)) continue;

                        /* Filter now! So num_engines and num_wagons is valid */
                        if (!FilterSingleEngine(eid)) continue;

                        *this->eng_list.Append() = eid;

                        if (rvi->railveh_type != RAILVEH_WAGON) {
                                num_engines++;
                        } else {
                                num_wagons++;
                        }

                        if (eid == this->sel_engine) sel_id = eid;
                }

                this->sel_engine = sel_id;

                /* make engines first, and then wagons, sorted by selected sort_criteria */
                _engine_sort_direction = false;
                EngList_Sort(&this->eng_list, TrainEnginesThenWagonsSorter);

                /* and then sort engines */
                _engine_sort_direction = this->descending_sort_order;
                EngList_SortPartial(&this->eng_list, _engine_sort_functions[0][this->sort_criteria], 0, num_engines);

                /* and finally sort wagons */
                EngList_SortPartial(&this->eng_list, _engine_sort_functions[0][this->sort_criteria], num_engines, num_wagons);
        }

        /* Figure out what road vehicle EngineIDs to put in the list */
        void GenerateBuildRoadVehList()
        {
                EngineID sel_id = INVALID_ENGINE;

                this->eng_list.Clear();

                const Engine *e;
                FOR_ALL_ENGINES_OF_TYPE(e, VEH_ROAD) {
                        if (!this->show_hidden_engines && e->IsHidden(_local_company)) continue;
                        EngineID eid = e->index;
                        if (!IsEngineBuildable(eid, VEH_ROAD, _local_company)) continue;
                        if (!HasBit(this->filter.roadtypes, HasBit(EngInfo(eid)->misc_flags, EF_ROAD_TRAM) ? ROADTYPE_TRAM : ROADTYPE_ROAD)) continue;
                        *this->eng_list.Append() = eid;

                        if (eid == this->sel_engine) sel_id = eid;
                }
                this->sel_engine = sel_id;
        }

        /* Figure out what ship EngineIDs to put in the list */
        void GenerateBuildShipList()
        {
                EngineID sel_id = INVALID_ENGINE;
                this->eng_list.Clear();

                const Engine *e;
                FOR_ALL_ENGINES_OF_TYPE(e, VEH_SHIP) {
                        if (!this->show_hidden_engines && e->IsHidden(_local_company)) continue;
                        EngineID eid = e->index;
                        if (!IsEngineBuildable(eid, VEH_SHIP, _local_company)) continue;
                        *this->eng_list.Append() = eid;

                        if (eid == this->sel_engine) sel_id = eid;
                }
                this->sel_engine = sel_id;
        }

        /* Figure out what aircraft EngineIDs to put in the list */
        void GenerateBuildAircraftList()
        {
                EngineID sel_id = INVALID_ENGINE;

                this->eng_list.Clear();

                const Station *st = this->listview_mode ? NULL : Station::GetByTile(this->window_number);

                /* Make list of all available planes.
                 * Also check to see if the previously selected plane is still available,
                 * and if not, reset selection to INVALID_ENGINE. This could be the case
                 * when planes become obsolete and are removed */
                const Engine *e;
                FOR_ALL_ENGINES_OF_TYPE(e, VEH_AIRCRAFT) {
                        if (!this->show_hidden_engines && e->IsHidden(_local_company)) continue;
                        EngineID eid = e->index;
                        if (!IsEngineBuildable(eid, VEH_AIRCRAFT, _local_company)) continue;
                        /* First VEH_END window_numbers are fake to allow a window open for all different types at once */
                        if (!this->listview_mode && !CanVehicleUseStation(eid, st)) continue;

                        *this->eng_list.Append() = eid;
                        if (eid == this->sel_engine) sel_id = eid;
                }

                this->sel_engine = sel_id;
        }

        /* Generate the list of vehicles */
        void GenerateBuildList()
        {
                if (!this->eng_list.NeedRebuild()) return;
                switch (this->vehicle_type) {
                        default: NOT_REACHED();
                        case VEH_TRAIN:
                                this->GenerateBuildTrainList();
                                this->eng_list.Compact();
                                this->eng_list.RebuildDone();
                                return; // trains should not reach the last sorting
                        case VEH_ROAD:
                                this->GenerateBuildRoadVehList();
                                break;
                        case VEH_SHIP:
                                this->GenerateBuildShipList();
                                break;
                        case VEH_AIRCRAFT:
                                this->GenerateBuildAircraftList();
                                break;
                }

                this->FilterEngineList();

                _engine_sort_direction = this->descending_sort_order;
                EngList_Sort(&this->eng_list, _engine_sort_functions[this->vehicle_type][this->sort_criteria]);

                this->eng_list.Compact();
                this->eng_list.RebuildDone();
        }

        void OnClick(Point pt, int widget, int click_count)
        {
                switch (widget) {
                        case WID_BV_SORT_ASCENDING_DESCENDING:
                                this->descending_sort_order ^= true;
                                _engine_sort_last_order[this->vehicle_type] = this->descending_sort_order;
                                this->eng_list.ForceRebuild();
                                this->SetDirty();
                                break;

                        case WID_BV_SHOW_HIDDEN_ENGINES:
                                this->show_hidden_engines ^= true;
                                _engine_sort_show_hidden_engines[this->vehicle_type] = this->show_hidden_engines;
                                this->eng_list.ForceRebuild();
                                this->SetWidgetLoweredState(widget, this->show_hidden_engines);
                                this->SetDirty();
                                break;

                        case WID_BV_LIST: {
                                uint i = this->vscroll->GetScrolledRowFromWidget(pt.y, this, WID_BV_LIST);
                                size_t num_items = this->eng_list.Length();
                                this->sel_engine = (i < num_items) ? this->eng_list[i] : INVALID_ENGINE;
                                this->SetDirty();
                                if (_ctrl_pressed) {
                                        this->OnClick(pt, WID_BV_SHOW_HIDE, 1);
                                } else if (click_count > 1 && !this->listview_mode) {
                                        this->OnClick(pt, WID_BV_BUILD, 1);
                                }
                                break;
                        }

                        case WID_BV_SORT_DROPDOWN: // Select sorting criteria dropdown menu
                                DisplayVehicleSortDropDown(this, this->vehicle_type, this->sort_criteria, WID_BV_SORT_DROPDOWN);
                                break;

                        case WID_BV_CARGO_FILTER_DROPDOWN: // Select cargo filtering criteria dropdown menu
                                ShowDropDownMenu(this, this->cargo_filter_texts, this->cargo_filter_criteria, WID_BV_CARGO_FILTER_DROPDOWN, 0, 0);
                                break;

                        case WID_BV_SHOW_HIDE: {
                                const Engine *e = (this->sel_engine == INVALID_ENGINE) ? NULL : Engine::Get(this->sel_engine);
                                if (e != NULL) {
                                        DoCommandP(0, 0, this->sel_engine | (e->IsHidden(_current_company) ? 0 : (1u << 31)), CMD_SET_VEHICLE_VISIBILITY);
                                }
                                break;
                        }

                        case WID_BV_BUILD: {
                                EngineID sel_eng = this->sel_engine;
                                if (sel_eng != INVALID_ENGINE) {
                                        CommandCallback *callback = (this->vehicle_type == VEH_TRAIN && RailVehInfo(sel_eng)->railveh_type == RAILVEH_WAGON) ? CcBuildWagon : CcBuildPrimaryVehicle;
                                        DoCommandP(this->window_number, sel_eng, 0, GetCmdBuildVeh(this->vehicle_type), callback);
                                }
                                break;
                        }

                        case WID_BV_RENAME: {
                                EngineID sel_eng = this->sel_engine;
                                if (sel_eng != INVALID_ENGINE) {
                                        this->rename_engine = sel_eng;
                                        SetDParam(0, sel_eng);
                                        ShowQueryString(STR_ENGINE_NAME, STR_QUERY_RENAME_TRAIN_TYPE_CAPTION + this->vehicle_type, MAX_LENGTH_ENGINE_NAME_CHARS, this, CS_ALPHANUMERAL, QSF_ENABLE_DEFAULT | QSF_LEN_IN_CHARS);
                                }
                                break;
                        }
                }
        }

        /**
         * 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.
         */
        virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
        {
                if (!gui_scope) return;
                /* When switching to original acceleration model for road vehicles, clear the selected sort criteria if it is not available now. */
                if (this->vehicle_type == VEH_ROAD &&
                                _settings_game.vehicle.roadveh_acceleration_model == AM_ORIGINAL &&
                                this->sort_criteria > 7) {
                        this->sort_criteria = 0;
                        _engine_sort_last_criteria[VEH_ROAD] = 0;
                }
                this->eng_list.ForceRebuild();
        }

        virtual void SetStringParameters(int widget) const
        {
                switch (widget) {
                        case WID_BV_CAPTION:
                                if (this->vehicle_type == VEH_TRAIN && !this->listview_mode) {
                                        const RailtypeInfo *rti = GetRailTypeInfo(this->filter.railtype);
                                        SetDParam(0, rti->strings.build_caption);
                                } else {
                                        SetDParam(0, (this->listview_mode ? STR_VEHICLE_LIST_AVAILABLE_TRAINS : STR_BUY_VEHICLE_TRAIN_ALL_CAPTION) + this->vehicle_type);
                                }
                                break;

                        case WID_BV_SORT_DROPDOWN:
                                SetDParam(0, _engine_sort_listing[this->vehicle_type][this->sort_criteria]);
                                break;

                        case WID_BV_CARGO_FILTER_DROPDOWN:
                                SetDParam(0, this->cargo_filter_texts[this->cargo_filter_criteria]);
                                break;

                        case WID_BV_SHOW_HIDE: {
                                const Engine *e = (this->sel_engine == INVALID_ENGINE) ? NULL : Engine::Get(this->sel_engine);
                                if (e != NULL && e->IsHidden(_local_company)) {
                                        SetDParam(0, STR_BUY_VEHICLE_TRAIN_SHOW_TOGGLE_BUTTON + this->vehicle_type);
                                } else {
                                        SetDParam(0, STR_BUY_VEHICLE_TRAIN_HIDE_TOGGLE_BUTTON + this->vehicle_type);
                                }
                                break;
                        }
                }
        }

        virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize)
        {
                switch (widget) {
                        case WID_BV_LIST:
                                resize->height = GetEngineListHeight(this->vehicle_type);
                                size->height = 3 * resize->height;
                                size->width = max(size->width, GetVehicleImageCellSize(this->vehicle_type, EIT_PURCHASE).extend_left + GetVehicleImageCellSize(this->vehicle_type, EIT_PURCHASE).extend_right + 165);
                                break;

                        case WID_BV_PANEL:
                                size->height = this->details_height;
                                break;

                        case WID_BV_SORT_ASCENDING_DESCENDING: {
                                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_BV_SHOW_HIDE:
                                *size = GetStringBoundingBox(STR_BUY_VEHICLE_TRAIN_HIDE_TOGGLE_BUTTON + this->vehicle_type);
                                *size = maxdim(*size, GetStringBoundingBox(STR_BUY_VEHICLE_TRAIN_SHOW_TOGGLE_BUTTON + this->vehicle_type));
                                size->width += padding.width;
                                size->height += padding.height;
                                break;
                }
        }

        virtual void DrawWidget(const Rect &r, int widget) const
        {
                switch (widget) {
                        case WID_BV_LIST:
                                DrawEngineList(this->vehicle_type, r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, r.top + WD_FRAMERECT_TOP, &this->eng_list, this->vscroll->GetPosition(), min(this->vscroll->GetPosition() + this->vscroll->GetCapacity(), this->eng_list.Length()), this->sel_engine, false, DEFAULT_GROUP);
                                break;

                        case WID_BV_SORT_ASCENDING_DESCENDING:
                                this->DrawSortButtonState(WID_BV_SORT_ASCENDING_DESCENDING, this->descending_sort_order ? SBS_DOWN : SBS_UP);
                                break;
                }
        }

        virtual void OnPaint()
        {
                this->GenerateBuildList();
                this->vscroll->SetCount(this->eng_list.Length());

                this->SetWidgetDisabledState(WID_BV_SHOW_HIDE, this->sel_engine == INVALID_ENGINE);

                this->DrawWidgets();

                if (!this->IsShaded()) {
                        int needed_height = this->details_height;
                        /* Draw details panels. */
                        if (this->sel_engine != INVALID_ENGINE) {
                                NWidgetBase *nwi = this->GetWidget<NWidgetBase>(WID_BV_PANEL);
                                int text_end = DrawVehiclePurchaseInfo(nwi->pos_x + WD_FRAMETEXT_LEFT, nwi->pos_x + nwi->current_x - WD_FRAMETEXT_RIGHT,
                                                nwi->pos_y + WD_FRAMERECT_TOP, this->sel_engine);
                                needed_height = max(needed_height, text_end - (int)nwi->pos_y + WD_FRAMERECT_BOTTOM);
                        }
                        if (needed_height != this->details_height) { // Details window are not high enough, enlarge them.
                                int resize = needed_height - this->details_height;
                                this->details_height = needed_height;
                                this->ReInit(0, resize);
                                return;
                        }
                }
        }

        virtual void OnQueryTextFinished(char *str)
        {
                if (str == NULL) return;

                DoCommandP(0, this->rename_engine, 0, CMD_RENAME_ENGINE | CMD_MSG(STR_ERROR_CAN_T_RENAME_TRAIN_TYPE + this->vehicle_type), NULL, str);
        }

        virtual void OnDropdownSelect(int widget, int index)
        {
                switch (widget) {
                        case WID_BV_SORT_DROPDOWN:
                                if (this->sort_criteria != index) {
                                        this->sort_criteria = index;
                                        _engine_sort_last_criteria[this->vehicle_type] = this->sort_criteria;
                                        this->eng_list.ForceRebuild();
                                }
                                break;

                        case WID_BV_CARGO_FILTER_DROPDOWN: // Select a cargo filter criteria
                                if (this->cargo_filter_criteria != index) {
                                        this->cargo_filter_criteria = index;
                                        _engine_sort_last_cargo_criteria[this->vehicle_type] = this->cargo_filter[this->cargo_filter_criteria];
                                        /* deactivate filter if criteria is 'Show All', activate it otherwise */
                                        this->eng_list.SetFilterState(this->cargo_filter[this->cargo_filter_criteria] != CF_ANY);
                                        this->eng_list.ForceRebuild();
                                }
                                break;
                }
                this->SetDirty();
        }

        virtual void OnResize()
        {
                this->vscroll->SetCapacityFromWidget(this, WID_BV_LIST);
        }
};

static WindowDesc _build_vehicle_desc(
        WDP_AUTO, "build_vehicle", 240, 268,
        WC_BUILD_VEHICLE, WC_NONE,
        WDF_CONSTRUCTION,
        _nested_build_vehicle_widgets, lengthof(_nested_build_vehicle_widgets)
);

void ShowBuildVehicleWindow(TileIndex tile, VehicleType type)
{
        /* We want to be able to open both Available Train as Available Ships,
         *  so if tile == INVALID_TILE (Available XXX Window), use 'type' as unique number.
         *  As it always is a low value, it won't collide with any real tile
         *  number. */
        uint num = (tile == INVALID_TILE) ? (int)type : tile;

        assert(IsCompanyBuildableVehicleType(type));

        DeleteWindowById(WC_BUILD_VEHICLE, num);

        new BuildVehicleWindow(&_build_vehicle_desc, tile, type);
}