Feature: Purchase land multiple tiles at a time

[openttd-github.git] / src / vehicle_cmd.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 vehicle_cmd.cpp Commands for vehicles. */

#include "stdafx.h"
#include "roadveh.h"
#include "news_func.h"
#include "airport.h"
#include "command_func.h"
#include "company_func.h"
#include "train.h"
#include "aircraft.h"
#include "newgrf_text.h"
#include "vehicle_func.h"
#include "string_func.h"
#include "depot_map.h"
#include "vehiclelist.h"
#include "engine_func.h"
#include "articulated_vehicles.h"
#include "autoreplace_gui.h"
#include "group.h"
#include "order_backup.h"
#include "ship.h"
#include "newgrf.h"
#include "company_base.h"
#include "core/random_func.hpp"
#include "vehicle_cmd.h"
#include "aircraft_cmd.h"
#include "autoreplace_cmd.h"
#include "group_cmd.h"
#include "order_cmd.h"
#include "roadveh_cmd.h"
#include "train_cmd.h"
#include "ship_cmd.h"
#include <sstream>
#include <iomanip>

#include "table/strings.h"

#include "safeguards.h"

/* Tables used in vehicle_func.h to find the right error message for a certain vehicle type */
const StringID _veh_build_msg_table[] = {
        STR_ERROR_CAN_T_BUY_TRAIN,
        STR_ERROR_CAN_T_BUY_ROAD_VEHICLE,
        STR_ERROR_CAN_T_BUY_SHIP,
        STR_ERROR_CAN_T_BUY_AIRCRAFT,
};

const StringID _veh_sell_msg_table[] = {
        STR_ERROR_CAN_T_SELL_TRAIN,
        STR_ERROR_CAN_T_SELL_ROAD_VEHICLE,
        STR_ERROR_CAN_T_SELL_SHIP,
        STR_ERROR_CAN_T_SELL_AIRCRAFT,
};

const StringID _veh_refit_msg_table[] = {
        STR_ERROR_CAN_T_REFIT_TRAIN,
        STR_ERROR_CAN_T_REFIT_ROAD_VEHICLE,
        STR_ERROR_CAN_T_REFIT_SHIP,
        STR_ERROR_CAN_T_REFIT_AIRCRAFT,
};

const StringID _send_to_depot_msg_table[] = {
        STR_ERROR_CAN_T_SEND_TRAIN_TO_DEPOT,
        STR_ERROR_CAN_T_SEND_ROAD_VEHICLE_TO_DEPOT,
        STR_ERROR_CAN_T_SEND_SHIP_TO_DEPOT,
        STR_ERROR_CAN_T_SEND_AIRCRAFT_TO_HANGAR,
};


/**
 * Build a vehicle.
 * @param flags for command
 * @param tile tile of depot where the vehicle is built
 * @param eid vehicle type being built.
 * @param use_free_vehicles use free vehicles when building the vehicle.
 * @param cargo refit cargo type.
 * @param client_id User
 * @return the cost of this operation + the new vehicle ID + the refitted capacity + the refitted mail capacity (aircraft) or an error
 */
std::tuple<CommandCost, VehicleID, uint, uint16> CmdBuildVehicle(DoCommandFlag flags, TileIndex tile, EngineID eid, bool use_free_vehicles, CargoID cargo, ClientID client_id)
{
        /* Elementary check for valid location. */
        if (!IsDepotTile(tile) || !IsTileOwner(tile, _current_company)) return { CMD_ERROR, INVALID_VEHICLE, 0, 0 };

        VehicleType type = GetDepotVehicleType(tile);

        /* Validate the engine type. */
        if (!IsEngineBuildable(eid, type, _current_company)) return { CommandCost(STR_ERROR_RAIL_VEHICLE_NOT_AVAILABLE + type), INVALID_VEHICLE, 0, 0 };

        /* Validate the cargo type. */
        if (cargo >= NUM_CARGO && cargo != CT_INVALID) return { CMD_ERROR, INVALID_VEHICLE, 0, 0 };

        const Engine *e = Engine::Get(eid);
        CommandCost value(EXPENSES_NEW_VEHICLES, e->GetCost());

        /* Engines without valid cargo should not be available */
        CargoID default_cargo = e->GetDefaultCargoType();
        if (default_cargo == CT_INVALID) return { CMD_ERROR, INVALID_VEHICLE, 0, 0 };

        bool refitting = cargo != CT_INVALID && cargo != default_cargo;

        /* Check whether the number of vehicles we need to build can be built according to pool space. */
        uint num_vehicles;
        switch (type) {
                case VEH_TRAIN:    num_vehicles = (e->u.rail.railveh_type == RAILVEH_MULTIHEAD ? 2 : 1) + CountArticulatedParts(eid, false); break;
                case VEH_ROAD:     num_vehicles = 1 + CountArticulatedParts(eid, false); break;
                case VEH_SHIP:     num_vehicles = 1; break;
                case VEH_AIRCRAFT: num_vehicles = e->u.air.subtype & AIR_CTOL ? 2 : 3; break;
                default: NOT_REACHED(); // Safe due to IsDepotTile()
        }
        if (!Vehicle::CanAllocateItem(num_vehicles)) return { CommandCost(STR_ERROR_TOO_MANY_VEHICLES_IN_GAME), INVALID_VEHICLE, 0, 0 };

        /* Check whether we can allocate a unit number. Autoreplace does not allocate
         * an unit number as it will (always) reuse the one of the replaced vehicle
         * and (train) wagons don't have an unit number in any scenario. */
        UnitID unit_num = (flags & DC_QUERY_COST || flags & DC_AUTOREPLACE || (type == VEH_TRAIN && e->u.rail.railveh_type == RAILVEH_WAGON)) ? 0 : GetFreeUnitNumber(type);
        if (unit_num == UINT16_MAX) return { CommandCost(STR_ERROR_TOO_MANY_VEHICLES_IN_GAME), INVALID_VEHICLE, 0, 0 };

        /* If we are refitting we need to temporarily purchase the vehicle to be able to
         * test it. */
        DoCommandFlag subflags = flags;
        if (refitting && !(flags & DC_EXEC)) subflags |= DC_EXEC | DC_AUTOREPLACE;

        /* Vehicle construction needs random bits, so we have to save the random
         * seeds to prevent desyncs. */
        SavedRandomSeeds saved_seeds;
        SaveRandomSeeds(&saved_seeds);

        Vehicle *v = nullptr;
        switch (type) {
                case VEH_TRAIN:    value.AddCost(CmdBuildRailVehicle(subflags, tile, e, use_free_vehicles, &v)); break;
                case VEH_ROAD:     value.AddCost(CmdBuildRoadVehicle(subflags, tile, e, &v)); break;
                case VEH_SHIP:     value.AddCost(CmdBuildShip       (subflags, tile, e, &v)); break;
                case VEH_AIRCRAFT: value.AddCost(CmdBuildAircraft   (subflags, tile, e, &v)); break;
                default: NOT_REACHED(); // Safe due to IsDepotTile()
        }

        VehicleID veh_id = INVALID_VEHICLE;
        uint refitted_capacity = 0;
        uint16 refitted_mail_capacity = 0;
        if (value.Succeeded()) {
                if (subflags & DC_EXEC) {
                        v->unitnumber = unit_num;
                        v->value      = value.GetCost();
                        veh_id        = v->index;
                }

                if (refitting) {
                        /* Refit only one vehicle. If we purchased an engine, it may have gained free wagons. */
                        CommandCost cc;
                        std::tie(cc, refitted_capacity, refitted_mail_capacity) = CmdRefitVehicle(flags, v->index, cargo, 0, false, false, 1);
                        value.AddCost(cc);
                } else {
                        /* Fill in non-refitted capacities */
                        refitted_capacity = e->GetDisplayDefaultCapacity(&refitted_mail_capacity);
                }

                if (flags & DC_EXEC) {
                        InvalidateWindowData(WC_VEHICLE_DEPOT, v->tile);
                        InvalidateWindowClassesData(GetWindowClassForVehicleType(type), 0);
                        SetWindowDirty(WC_COMPANY, _current_company);
                        if (IsLocalCompany()) {
                                InvalidateAutoreplaceWindow(v->engine_type, v->group_id); // updates the auto replace window (must be called before incrementing num_engines)
                        }
                }

                if (subflags & DC_EXEC) {
                        GroupStatistics::CountEngine(v, 1);
                        GroupStatistics::UpdateAutoreplace(_current_company);

                        if (v->IsPrimaryVehicle()) {
                                GroupStatistics::CountVehicle(v, 1);
                                if (!(subflags & DC_AUTOREPLACE)) OrderBackup::Restore(v, client_id);
                        }
                }


                /* If we are not in DC_EXEC undo everything */
                if (flags != subflags) {
                        Command<CMD_SELL_VEHICLE>::Do(DC_EXEC, v->index, false, false, INVALID_CLIENT_ID);
                }
        }

        /* Only restore if we actually did some refitting */
        if (flags != subflags) RestoreRandomSeeds(saved_seeds);

        return { value, veh_id, refitted_capacity, refitted_mail_capacity };
}

/**
 * Sell a vehicle.
 * @param flags for command.
 * @param v_id vehicle ID being sold.
 * @param sell_chain sell the vehicle and all vehicles following it in the chain.
 * @param backup_order make a backup of the vehicle's order (if an engine).
 * @param client_id User.
 * @return the cost of this operation or an error.
 */
CommandCost CmdSellVehicle(DoCommandFlag flags, VehicleID v_id, bool sell_chain, bool backup_order, ClientID client_id)
{
        Vehicle *v = Vehicle::GetIfValid(v_id);
        if (v == nullptr) return CMD_ERROR;

        Vehicle *front = v->First();

        CommandCost ret = CheckOwnership(front->owner);
        if (ret.Failed()) return ret;

        if (front->vehstatus & VS_CRASHED) return_cmd_error(STR_ERROR_VEHICLE_IS_DESTROYED);

        if (!front->IsStoppedInDepot()) return_cmd_error(STR_ERROR_TRAIN_MUST_BE_STOPPED_INSIDE_DEPOT + front->type);

        /* Can we actually make the order backup, i.e. are there enough orders? */
        if (backup_order &&
                        front->orders != nullptr &&
                        !front->orders->IsShared() &&
                        !Order::CanAllocateItem(front->orders->GetNumOrders())) {
                /* Only happens in exceptional cases when there aren't enough orders anyhow.
                 * Thus it should be safe to just drop the orders in that case. */
                backup_order = false;
        }

        if (v->type == VEH_TRAIN) {
                ret = CmdSellRailWagon(flags, v, sell_chain, backup_order, client_id);
        } else {
                ret = CommandCost(EXPENSES_NEW_VEHICLES, -front->value);

                if (flags & DC_EXEC) {
                        if (front->IsPrimaryVehicle() && backup_order) OrderBackup::Backup(front, client_id);
                        delete front;
                }
        }

        return ret;
}

/**
 * Helper to run the refit cost callback.
 * @param v The vehicle we are refitting, can be nullptr.
 * @param engine_type Which engine to refit
 * @param new_cid Cargo type we are refitting to.
 * @param new_subtype New cargo subtype.
 * @param[out] auto_refit_allowed The refit is allowed as an auto-refit.
 * @return Price for refitting
 */
static int GetRefitCostFactor(const Vehicle *v, EngineID engine_type, CargoID new_cid, byte new_subtype, bool *auto_refit_allowed)
{
        /* Prepare callback param with info about the new cargo type. */
        const Engine *e = Engine::Get(engine_type);

        /* Is this vehicle a NewGRF vehicle? */
        if (e->GetGRF() != nullptr) {
                const CargoSpec *cs = CargoSpec::Get(new_cid);
                uint32 param1 = (cs->classes << 16) | (new_subtype << 8) | e->GetGRF()->cargo_map[new_cid];

                uint16 cb_res = GetVehicleCallback(CBID_VEHICLE_REFIT_COST, param1, 0, engine_type, v);
                if (cb_res != CALLBACK_FAILED) {
                        *auto_refit_allowed = HasBit(cb_res, 14);
                        int factor = GB(cb_res, 0, 14);
                        if (factor >= 0x2000) factor -= 0x4000; // Treat as signed integer.
                        return factor;
                }
        }

        *auto_refit_allowed = e->info.refit_cost == 0;
        return (v == nullptr || v->cargo_type != new_cid) ? e->info.refit_cost : 0;
}

/**
 * Learn the price of refitting a certain engine
 * @param v The vehicle we are refitting, can be nullptr.
 * @param engine_type Which engine to refit
 * @param new_cid Cargo type we are refitting to.
 * @param new_subtype New cargo subtype.
 * @param[out] auto_refit_allowed The refit is allowed as an auto-refit.
 * @return Price for refitting
 */
static CommandCost GetRefitCost(const Vehicle *v, EngineID engine_type, CargoID new_cid, byte new_subtype, bool *auto_refit_allowed)
{
        ExpensesType expense_type;
        const Engine *e = Engine::Get(engine_type);
        Price base_price;
        int cost_factor = GetRefitCostFactor(v, engine_type, new_cid, new_subtype, auto_refit_allowed);
        switch (e->type) {
                case VEH_SHIP:
                        base_price = PR_BUILD_VEHICLE_SHIP;
                        expense_type = EXPENSES_SHIP_RUN;
                        break;

                case VEH_ROAD:
                        base_price = PR_BUILD_VEHICLE_ROAD;
                        expense_type = EXPENSES_ROADVEH_RUN;
                        break;

                case VEH_AIRCRAFT:
                        base_price = PR_BUILD_VEHICLE_AIRCRAFT;
                        expense_type = EXPENSES_AIRCRAFT_RUN;
                        break;

                case VEH_TRAIN:
                        base_price = (e->u.rail.railveh_type == RAILVEH_WAGON) ? PR_BUILD_VEHICLE_WAGON : PR_BUILD_VEHICLE_TRAIN;
                        cost_factor <<= 1;
                        expense_type = EXPENSES_TRAIN_RUN;
                        break;

                default: NOT_REACHED();
        }
        if (cost_factor < 0) {
                return CommandCost(expense_type, -GetPrice(base_price, -cost_factor, e->GetGRF(), -10));
        } else {
                return CommandCost(expense_type, GetPrice(base_price, cost_factor, e->GetGRF(), -10));
        }
}

/** Helper structure for RefitVehicle() */
struct RefitResult {
        Vehicle *v;         ///< Vehicle to refit
        uint capacity;      ///< New capacity of vehicle
        uint mail_capacity; ///< New mail capacity of aircraft
        byte subtype;       ///< cargo subtype to refit to
};

/**
 * Refits a vehicle (chain).
 * This is the vehicle-type independent part of the CmdRefitXXX functions.
 * @param v            The vehicle to refit.
 * @param only_this    Whether to only refit this vehicle, or to check the rest of them.
 * @param num_vehicles Number of vehicles to refit (not counting articulated parts). Zero means the whole chain.
 * @param new_cid      Cargotype to refit to
 * @param new_subtype  Cargo subtype to refit to. 0xFF means to try keeping the same subtype according to GetBestFittingSubType().
 * @param flags        Command flags
 * @param auto_refit   Refitting is done as automatic refitting outside a depot.
 * @return Refit cost + refittet capacity + mail capacity (aircraft).
 */
static std::tuple<CommandCost, uint, uint16> RefitVehicle(Vehicle *v, bool only_this, uint8 num_vehicles, CargoID new_cid, byte new_subtype, DoCommandFlag flags, bool auto_refit)
{
        CommandCost cost(v->GetExpenseType(false));
        uint total_capacity = 0;
        uint total_mail_capacity = 0;
        num_vehicles = num_vehicles == 0 ? UINT8_MAX : num_vehicles;

        VehicleSet vehicles_to_refit;
        if (!only_this) {
                GetVehicleSet(vehicles_to_refit, v, num_vehicles);
                /* In this case, we need to check the whole chain. */
                v = v->First();
        }

        std::vector<RefitResult> refit_result;

        v->InvalidateNewGRFCacheOfChain();
        byte actual_subtype = new_subtype;
        for (; v != nullptr; v = (only_this ? nullptr : v->Next())) {
                /* Reset actual_subtype for every new vehicle */
                if (!v->IsArticulatedPart()) actual_subtype = new_subtype;

                if (v->type == VEH_TRAIN && std::find(vehicles_to_refit.begin(), vehicles_to_refit.end(), v->index) == vehicles_to_refit.end() && !only_this) continue;

                const Engine *e = v->GetEngine();
                if (!e->CanCarryCargo()) continue;

                /* If the vehicle is not refittable, or does not allow automatic refitting,
                 * count its capacity nevertheless if the cargo matches */
                bool refittable = HasBit(e->info.refit_mask, new_cid) && (!auto_refit || HasBit(e->info.misc_flags, EF_AUTO_REFIT));
                if (!refittable && v->cargo_type != new_cid) continue;

                /* Determine best fitting subtype if requested */
                if (actual_subtype == 0xFF) {
                        actual_subtype = GetBestFittingSubType(v, v, new_cid);
                }

                /* Back up the vehicle's cargo type */
                CargoID temp_cid = v->cargo_type;
                byte temp_subtype = v->cargo_subtype;
                if (refittable) {
                        v->cargo_type = new_cid;
                        v->cargo_subtype = actual_subtype;
                }

                uint16 mail_capacity = 0;
                uint amount = e->DetermineCapacity(v, &mail_capacity);
                total_capacity += amount;
                /* mail_capacity will always be zero if the vehicle is not an aircraft. */
                total_mail_capacity += mail_capacity;

                if (!refittable) continue;

                /* Restore the original cargo type */
                v->cargo_type = temp_cid;
                v->cargo_subtype = temp_subtype;

                bool auto_refit_allowed;
                CommandCost refit_cost = GetRefitCost(v, v->engine_type, new_cid, actual_subtype, &auto_refit_allowed);
                if (auto_refit && (flags & DC_QUERY_COST) == 0 && !auto_refit_allowed) {
                        /* Sorry, auto-refitting not allowed, subtract the cargo amount again from the total.
                         * When querrying cost/capacity (for example in order refit GUI), we always assume 'allowed'.
                         * It is not predictable. */
                        total_capacity -= amount;
                        total_mail_capacity -= mail_capacity;

                        if (v->cargo_type == new_cid) {
                                /* Add the old capacity nevertheless, if the cargo matches */
                                total_capacity += v->cargo_cap;
                                if (v->type == VEH_AIRCRAFT) total_mail_capacity += v->Next()->cargo_cap;
                        }
                        continue;
                }
                cost.AddCost(refit_cost);

                /* Record the refitting.
                 * Do not execute the refitting immediately, so DetermineCapacity and GetRefitCost do the same in test and exec run.
                 * (weird NewGRFs)
                 * Note:
                 *  - If the capacity of vehicles depends on other vehicles in the chain, the actual capacity is
                 *    set after RefitVehicle() via ConsistChanged() and friends. The estimation via _returned_refit_capacity will be wrong.
                 *  - We have to call the refit cost callback with the pre-refit configuration of the chain because we want refit and
                 *    autorefit to behave the same, and we need its result for auto_refit_allowed.
                 */
                refit_result.push_back({v, amount, mail_capacity, actual_subtype});
        }

        if (flags & DC_EXEC) {
                /* Store the result */
                for (RefitResult &result : refit_result) {
                        Vehicle *u = result.v;
                        u->refit_cap = (u->cargo_type == new_cid) ? std::min<uint16>(result.capacity, u->refit_cap) : 0;
                        if (u->cargo.TotalCount() > u->refit_cap) u->cargo.Truncate(u->cargo.TotalCount() - u->refit_cap);
                        u->cargo_type = new_cid;
                        u->cargo_cap = result.capacity;
                        u->cargo_subtype = result.subtype;
                        if (u->type == VEH_AIRCRAFT) {
                                Vehicle *w = u->Next();
                                w->refit_cap = std::min<uint16>(w->refit_cap, result.mail_capacity);
                                w->cargo_cap = result.mail_capacity;
                                if (w->cargo.TotalCount() > w->refit_cap) w->cargo.Truncate(w->cargo.TotalCount() - w->refit_cap);
                        }
                }
        }

        refit_result.clear();
        return { cost, total_capacity, total_mail_capacity };
}

/**
 * Refits a vehicle to the specified cargo type.
 * @param flags type of operation
 * @param veh_id vehicle ID to refit
 * @param new_cid New cargo type to refit to.
 * @param new_subtype New cargo subtype to refit to. 0xFF means to try keeping the same subtype according to GetBestFittingSubType().
 * @param auto_refit Automatic refitting.
 * @param only_this Refit only this vehicle. Used only for cloning vehicles.
 * @param num_vehicles Number of vehicles to refit (not counting articulated parts). Zero means all vehicles.
 *                     Only used if "refit only this vehicle" is false.
 * @return the cost of this operation or an error
 */
std::tuple<CommandCost, uint, uint16> CmdRefitVehicle(DoCommandFlag flags, VehicleID veh_id, CargoID new_cid, byte new_subtype, bool auto_refit, bool only_this, uint8 num_vehicles)
{
        Vehicle *v = Vehicle::GetIfValid(veh_id);
        if (v == nullptr) return { CMD_ERROR, 0, 0 };

        /* Don't allow disasters and sparks and such to be refitted.
         * We cannot check for IsPrimaryVehicle as autoreplace also refits in free wagon chains. */
        if (!IsCompanyBuildableVehicleType(v->type)) return { CMD_ERROR, 0, 0 };

        Vehicle *front = v->First();

        CommandCost ret = CheckOwnership(front->owner);
        if (ret.Failed()) return { ret, 0, 0 };

        bool free_wagon = v->type == VEH_TRAIN && Train::From(front)->IsFreeWagon(); // used by autoreplace/renew

        /* Don't allow shadows and such to be refitted. */
        if (v != front && (v->type == VEH_SHIP || v->type == VEH_AIRCRAFT)) return { CMD_ERROR, 0, 0 };

        /* Allow auto-refitting only during loading and normal refitting only in a depot. */
        if ((flags & DC_QUERY_COST) == 0 && // used by the refit GUI, including the order refit GUI.
                        !free_wagon && // used by autoreplace/renew
                        (!auto_refit || !front->current_order.IsType(OT_LOADING)) && // refit inside stations
                        !front->IsStoppedInDepot()) { // refit inside depots
                return { CommandCost(STR_ERROR_TRAIN_MUST_BE_STOPPED_INSIDE_DEPOT + front->type), 0, 0};
        }

        if (front->vehstatus & VS_CRASHED) return { CommandCost(STR_ERROR_VEHICLE_IS_DESTROYED), 0, 0};

        /* Check cargo */
        if (new_cid >= NUM_CARGO) return { CMD_ERROR, 0, 0 };

        /* For ships and aircraft there is always only one. */
        only_this |= front->type == VEH_SHIP || front->type == VEH_AIRCRAFT;

        auto [cost, refit_capacity, mail_capacity] = RefitVehicle(v, only_this, num_vehicles, new_cid, new_subtype, flags, auto_refit);

        if (flags & DC_EXEC) {
                /* Update the cached variables */
                switch (v->type) {
                        case VEH_TRAIN:
                                Train::From(front)->ConsistChanged(auto_refit ? CCF_AUTOREFIT : CCF_REFIT);
                                break;
                        case VEH_ROAD:
                                RoadVehUpdateCache(RoadVehicle::From(front), auto_refit);
                                if (_settings_game.vehicle.roadveh_acceleration_model != AM_ORIGINAL) RoadVehicle::From(front)->CargoChanged();
                                break;

                        case VEH_SHIP:
                                v->InvalidateNewGRFCacheOfChain();
                                Ship::From(v)->UpdateCache();
                                break;

                        case VEH_AIRCRAFT:
                                v->InvalidateNewGRFCacheOfChain();
                                UpdateAircraftCache(Aircraft::From(v), true);
                                break;

                        default: NOT_REACHED();
                }
                front->MarkDirty();

                if (!free_wagon) {
                        InvalidateWindowData(WC_VEHICLE_DETAILS, front->index);
                        InvalidateWindowClassesData(GetWindowClassForVehicleType(v->type), 0);
                }
                SetWindowDirty(WC_VEHICLE_DEPOT, front->tile);
        } else {
                /* Always invalidate the cache; querycost might have filled it. */
                v->InvalidateNewGRFCacheOfChain();
        }

        return { cost, refit_capacity, mail_capacity };
}

/**
 * Start/Stop a vehicle
 * @param flags type of operation
 * @param veh_id vehicle to start/stop, don't forget to change CcStartStopVehicle if you modify this!
 * @param evaluate_startstop_cb Shall the start/stop newgrf callback be evaluated (only valid with DC_AUTOREPLACE for network safety)
 * @return the cost of this operation or an error
 */
CommandCost CmdStartStopVehicle(DoCommandFlag flags, VehicleID veh_id, bool evaluate_startstop_cb)
{
        /* Disable the effect of p2 bit 0, when DC_AUTOREPLACE is not set */
        if ((flags & DC_AUTOREPLACE) == 0) evaluate_startstop_cb = true;

        Vehicle *v = Vehicle::GetIfValid(veh_id);
        if (v == nullptr || !v->IsPrimaryVehicle()) return CMD_ERROR;

        CommandCost ret = CheckOwnership(v->owner);
        if (ret.Failed()) return ret;

        if (v->vehstatus & VS_CRASHED) return_cmd_error(STR_ERROR_VEHICLE_IS_DESTROYED);

        switch (v->type) {
                case VEH_TRAIN:
                        if ((v->vehstatus & VS_STOPPED) && Train::From(v)->gcache.cached_power == 0) return_cmd_error(STR_ERROR_TRAIN_START_NO_POWER);
                        break;

                case VEH_SHIP:
                case VEH_ROAD:
                        break;

                case VEH_AIRCRAFT: {
                        Aircraft *a = Aircraft::From(v);
                        /* cannot stop airplane when in flight, or when taking off / landing */
                        if (a->state >= STARTTAKEOFF && a->state < TERM7) return_cmd_error(STR_ERROR_AIRCRAFT_IS_IN_FLIGHT);
                        if (HasBit(a->flags, VAF_HELI_DIRECT_DESCENT)) return_cmd_error(STR_ERROR_AIRCRAFT_IS_IN_FLIGHT);
                        break;
                }

                default: return CMD_ERROR;
        }

        if (evaluate_startstop_cb) {
                /* Check if this vehicle can be started/stopped. Failure means 'allow'. */
                uint16 callback = GetVehicleCallback(CBID_VEHICLE_START_STOP_CHECK, 0, 0, v->engine_type, v);
                StringID error = STR_NULL;
                if (callback != CALLBACK_FAILED) {
                        if (v->GetGRF()->grf_version < 8) {
                                /* 8 bit result 0xFF means 'allow' */
                                if (callback < 0x400 && GB(callback, 0, 8) != 0xFF) error = GetGRFStringID(v->GetGRFID(), 0xD000 + callback);
                        } else {
                                if (callback < 0x400) {
                                        error = GetGRFStringID(v->GetGRFID(), 0xD000 + callback);
                                } else {
                                        switch (callback) {
                                                case 0x400: // allow
                                                        break;

                                                default: // unknown reason -> disallow
                                                        error = STR_ERROR_INCOMPATIBLE_RAIL_TYPES;
                                                        break;
                                        }
                                }
                        }
                }
                if (error != STR_NULL) return_cmd_error(error);
        }

        if (flags & DC_EXEC) {
                if (v->IsStoppedInDepot() && (flags & DC_AUTOREPLACE) == 0) DeleteVehicleNews(veh_id, STR_NEWS_TRAIN_IS_WAITING + v->type);

                v->vehstatus ^= VS_STOPPED;
                if (v->type != VEH_TRAIN) v->cur_speed = 0; // trains can stop 'slowly'
                v->MarkDirty();
                SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
                SetWindowDirty(WC_VEHICLE_DEPOT, v->tile);
                SetWindowClassesDirty(GetWindowClassForVehicleType(v->type));
                InvalidateWindowData(WC_VEHICLE_VIEW, v->index);
        }
        return CommandCost();
}

/**
 * Starts or stops a lot of vehicles
 * @param flags type of operation
 * @param tile Tile of the depot where the vehicles are started/stopped (only used for depots)
 * @param do_start set = start vehicles, unset = stop vehicles
 * @param vehicle_list_window if set, then it's a vehicle list window, not a depot and Tile is ignored in this case
 * @param vli VehicleListIdentifier
 * @return the cost of this operation or an error
 */
CommandCost CmdMassStartStopVehicle(DoCommandFlag flags, TileIndex tile, bool do_start, bool vehicle_list_window, const VehicleListIdentifier &vli)
{
        VehicleList list;

        if (!vli.Valid()) return CMD_ERROR;
        if (!IsCompanyBuildableVehicleType(vli.vtype)) return CMD_ERROR;

        if (vehicle_list_window) {
                if (!GenerateVehicleSortList(&list, vli)) return CMD_ERROR;
        } else {
                if (!IsDepotTile(tile) || !IsTileOwner(tile, _current_company)) return CMD_ERROR;
                /* Get the list of vehicles in the depot */
                BuildDepotVehicleList(vli.vtype, tile, &list, nullptr);
        }

        for (uint i = 0; i < list.size(); i++) {
                const Vehicle *v = list[i];

                if (!!(v->vehstatus & VS_STOPPED) != do_start) continue;

                if (!vehicle_list_window && !v->IsChainInDepot()) continue;

                /* Just try and don't care if some vehicle's can't be stopped. */
                Command<CMD_START_STOP_VEHICLE>::Do(flags, v->index, false);
        }

        return CommandCost();
}

/**
 * Sells all vehicles in a depot
 * @param flags type of operation
 * @param tile Tile of the depot where the depot is
 * @param vehicle_type Vehicle type
 * @return the cost of this operation or an error
 */
CommandCost CmdDepotSellAllVehicles(DoCommandFlag flags, TileIndex tile, VehicleType vehicle_type)
{
        VehicleList list;

        CommandCost cost(EXPENSES_NEW_VEHICLES);

        if (!IsCompanyBuildableVehicleType(vehicle_type)) return CMD_ERROR;
        if (!IsDepotTile(tile) || !IsTileOwner(tile, _current_company)) return CMD_ERROR;

        /* Get the list of vehicles in the depot */
        BuildDepotVehicleList(vehicle_type, tile, &list, &list);

        CommandCost last_error = CMD_ERROR;
        bool had_success = false;
        for (uint i = 0; i < list.size(); i++) {
                CommandCost ret = Command<CMD_SELL_VEHICLE>::Do(flags, list[i]->index, true, false, INVALID_CLIENT_ID);
                if (ret.Succeeded()) {
                        cost.AddCost(ret);
                        had_success = true;
                } else {
                        last_error = ret;
                }
        }

        return had_success ? cost : last_error;
}

/**
 * Autoreplace all vehicles in the depot
 * @param flags type of operation
 * @param tile Tile of the depot where the vehicles are
 * @param vehicle_type Type of vehicle
 * @return the cost of this operation or an error
 */
CommandCost CmdDepotMassAutoReplace(DoCommandFlag flags, TileIndex tile, VehicleType vehicle_type)
{
        VehicleList list;
        CommandCost cost = CommandCost(EXPENSES_NEW_VEHICLES);

        if (!IsCompanyBuildableVehicleType(vehicle_type)) return CMD_ERROR;
        if (!IsDepotTile(tile) || !IsTileOwner(tile, _current_company)) return CMD_ERROR;

        /* Get the list of vehicles in the depot */
        BuildDepotVehicleList(vehicle_type, tile, &list, &list, true);

        for (uint i = 0; i < list.size(); i++) {
                const Vehicle *v = list[i];

                /* Ensure that the vehicle completely in the depot */
                if (!v->IsChainInDepot()) continue;

                CommandCost ret = Command<CMD_AUTOREPLACE_VEHICLE>::Do(flags, v->index);

                if (ret.Succeeded()) cost.AddCost(ret);
        }
        return cost;
}

/**
 * Test if a name is unique among vehicle names.
 * @param name Name to test.
 * @return True ifffffff the name is unique.
 */
static bool IsUniqueVehicleName(const std::string &name)
{
        for (const Vehicle *v : Vehicle::Iterate()) {
                if (!v->name.empty() && v->name == name) return false;
        }

        return true;
}

/**
 * Clone the custom name of a vehicle, adding or incrementing a number.
 * @param src Source vehicle, with a custom name.
 * @param dst Destination vehicle.
 */
static void CloneVehicleName(const Vehicle *src, Vehicle *dst)
{
        std::string buf;

        /* Find the position of the first digit in the last group of digits. */
        size_t number_position;
        for (number_position = src->name.length(); number_position > 0; number_position--) {
                /* The design of UTF-8 lets this work simply without having to check
                 * for UTF-8 sequences. */
                if (src->name[number_position - 1] < '0' || src->name[number_position - 1] > '9') break;
        }

        /* Format buffer and determine starting number. */
        long num;
        byte padding = 0;
        if (number_position == src->name.length()) {
                /* No digit at the end, so start at number 2. */
                buf = src->name;
                buf += " ";
                number_position = buf.length();
                num = 2;
        } else {
                /* Found digits, parse them and start at the next number. */
                buf = src->name.substr(0, number_position);

                auto num_str = src->name.substr(number_position);
                padding = (byte)num_str.length();

                std::istringstream iss(num_str);
                iss >> num;
                num++;
        }

        /* Check if this name is already taken. */
        for (int max_iterations = 1000; max_iterations > 0; max_iterations--, num++) {
                std::ostringstream oss;

                /* Attach the number to the temporary name. */
                oss << buf << std::setw(padding) << std::setfill('0') << std::internal << num;

                /* Check the name is unique. */
                auto new_name = oss.str();
                if (IsUniqueVehicleName(new_name)) {
                        dst->name = new_name;
                        break;
                }
        }

        /* All done. If we didn't find a name, it'll just use its default. */
}

/**
 * Clone a vehicle. If it is a train, it will clone all the cars too
 * @param flags type of operation
 * @param tile tile of the depot where the cloned vehicle is build
 * @param veh_id the original vehicle's index
 * @param share_orders shared orders, else copied orders
 * @return the cost of this operation + the new vehicle ID or an error
 */
std::tuple<CommandCost, VehicleID> CmdCloneVehicle(DoCommandFlag flags, TileIndex tile, VehicleID veh_id, bool share_orders)
{
        CommandCost total_cost(EXPENSES_NEW_VEHICLES);

        Vehicle *v = Vehicle::GetIfValid(veh_id);
        if (v == nullptr || !v->IsPrimaryVehicle()) return { CMD_ERROR, INVALID_VEHICLE };
        Vehicle *v_front = v;
        Vehicle *w = nullptr;
        Vehicle *w_front = nullptr;
        Vehicle *w_rear = nullptr;

        /*
         * v_front is the front engine in the original vehicle
         * v is the car/vehicle of the original vehicle that is currently being copied
         * w_front is the front engine of the cloned vehicle
         * w is the car/vehicle currently being cloned
         * w_rear is the rear end of the cloned train. It's used to add more cars and is only used by trains
         */

        CommandCost ret = CheckOwnership(v->owner);
        if (ret.Failed()) return { ret, INVALID_VEHICLE };

        if (v->type == VEH_TRAIN && (!v->IsFrontEngine() || Train::From(v)->crash_anim_pos >= 4400)) return { CMD_ERROR, INVALID_VEHICLE };

        /* check that we can allocate enough vehicles */
        if (!(flags & DC_EXEC)) {
                int veh_counter = 0;
                do {
                        veh_counter++;
                } while ((v = v->Next()) != nullptr);

                if (!Vehicle::CanAllocateItem(veh_counter)) {
                        return { CommandCost(STR_ERROR_TOO_MANY_VEHICLES_IN_GAME), INVALID_VEHICLE };
                }
        }

        v = v_front;

        VehicleID new_veh_id = INVALID_VEHICLE;
        do {
                if (v->type == VEH_TRAIN && Train::From(v)->IsRearDualheaded()) {
                        /* we build the rear ends of multiheaded trains with the front ones */
                        continue;
                }

                /* In case we're building a multi headed vehicle and the maximum number of
                 * vehicles is almost reached (e.g. max trains - 1) not all vehicles would
                 * be cloned. When the non-primary engines were build they were seen as
                 * 'new' vehicles whereas they would immediately be joined with a primary
                 * engine. This caused the vehicle to be not build as 'the limit' had been
                 * reached, resulting in partially build vehicles and such. */
                DoCommandFlag build_flags = flags;
                if ((flags & DC_EXEC) && !v->IsPrimaryVehicle()) build_flags |= DC_AUTOREPLACE;

                CommandCost cost;
                std::tie(cost, new_veh_id, std::ignore, std::ignore) = Command<CMD_BUILD_VEHICLE>::Do(build_flags, tile, v->engine_type, false, CT_INVALID, INVALID_CLIENT_ID);

                if (cost.Failed()) {
                        /* Can't build a part, then sell the stuff we already made; clear up the mess */
                        if (w_front != nullptr) Command<CMD_SELL_VEHICLE>::Do(flags, w_front->index, true, false, INVALID_CLIENT_ID);
                        return { cost, INVALID_VEHICLE };
                }

                total_cost.AddCost(cost);

                if (flags & DC_EXEC) {
                        w = Vehicle::Get(new_veh_id);

                        if (v->type == VEH_TRAIN && HasBit(Train::From(v)->flags, VRF_REVERSE_DIRECTION)) {
                                SetBit(Train::From(w)->flags, VRF_REVERSE_DIRECTION);
                        }

                        if (v->type == VEH_TRAIN && !v->IsFrontEngine()) {
                                /* this s a train car
                                 * add this unit to the end of the train */
                                CommandCost result = Command<CMD_MOVE_RAIL_VEHICLE>::Do(flags, w->index, w_rear->index, true);
                                if (result.Failed()) {
                                        /* The train can't be joined to make the same consist as the original.
                                         * Sell what we already made (clean up) and return an error.           */
                                        Command<CMD_SELL_VEHICLE>::Do(flags, w_front->index, true, false, INVALID_CLIENT_ID);
                                        Command<CMD_SELL_VEHICLE>::Do(flags, w->index,       true, false, INVALID_CLIENT_ID);
                                        return { result, INVALID_VEHICLE }; // return error and the message returned from CMD_MOVE_RAIL_VEHICLE
                                }
                        } else {
                                /* this is a front engine or not a train. */
                                w_front = w;
                                w->service_interval = v->service_interval;
                                w->SetServiceIntervalIsCustom(v->ServiceIntervalIsCustom());
                                w->SetServiceIntervalIsPercent(v->ServiceIntervalIsPercent());
                        }
                        w_rear = w; // trains needs to know the last car in the train, so they can add more in next loop
                }
        } while (v->type == VEH_TRAIN && (v = v->GetNextVehicle()) != nullptr);

        if ((flags & DC_EXEC) && v_front->type == VEH_TRAIN) {
                /* for trains this needs to be the front engine due to the callback function */
                new_veh_id = w_front->index;
        }

        if (flags & DC_EXEC) {
                /* Cloned vehicles belong to the same group */
                Command<CMD_ADD_VEHICLE_GROUP>::Do(flags, v_front->group_id, w_front->index, false);
        }


        /* Take care of refitting. */
        w = w_front;
        v = v_front;

        /* Both building and refitting are influenced by newgrf callbacks, which
         * makes it impossible to accurately estimate the cloning costs. In
         * particular, it is possible for engines of the same type to be built with
         * different numbers of articulated parts, so when refitting we have to
         * loop over real vehicles first, and then the articulated parts of those
         * vehicles in a different loop. */
        do {
                do {
                        if (flags & DC_EXEC) {
                                assert(w != nullptr);

                                /* Find out what's the best sub type */
                                byte subtype = GetBestFittingSubType(v, w, v->cargo_type);
                                if (w->cargo_type != v->cargo_type || w->cargo_subtype != subtype) {
                                        CommandCost cost = std::get<0>(Command<CMD_REFIT_VEHICLE>::Do(flags, w->index, v->cargo_type, subtype, false, true, 0));
                                        if (cost.Succeeded()) total_cost.AddCost(cost);
                                }

                                if (w->IsGroundVehicle() && w->HasArticulatedPart()) {
                                        w = w->GetNextArticulatedPart();
                                } else {
                                        break;
                                }
                        } else {
                                const Engine *e = v->GetEngine();
                                CargoID initial_cargo = (e->CanCarryCargo() ? e->GetDefaultCargoType() : (CargoID)CT_INVALID);

                                if (v->cargo_type != initial_cargo && initial_cargo != CT_INVALID) {
                                        bool dummy;
                                        total_cost.AddCost(GetRefitCost(nullptr, v->engine_type, v->cargo_type, v->cargo_subtype, &dummy));
                                }
                        }

                        if (v->IsGroundVehicle() && v->HasArticulatedPart()) {
                                v = v->GetNextArticulatedPart();
                        } else {
                                break;
                        }
                } while (v != nullptr);

                if ((flags & DC_EXEC) && v->type == VEH_TRAIN) w = w->GetNextVehicle();
        } while (v->type == VEH_TRAIN && (v = v->GetNextVehicle()) != nullptr);

        if (flags & DC_EXEC) {
                /*
                 * Set the orders of the vehicle. Cannot do it earlier as we need
                 * the vehicle refitted before doing this, otherwise the moved
                 * cargo types might not match (passenger vs non-passenger)
                 */
                CommandCost result = Command<CMD_CLONE_ORDER>::Do(flags, (share_orders ? CO_SHARE : CO_COPY), w_front->index, v_front->index);
                if (result.Failed()) {
                        /* The vehicle has already been bought, so now it must be sold again. */
                        Command<CMD_SELL_VEHICLE>::Do(flags, w_front->index, true, false, INVALID_CLIENT_ID);
                        return { total_cost, INVALID_VEHICLE };
                }

                /* Now clone the vehicle's name, if it has one. */
                if (!v_front->name.empty()) CloneVehicleName(v_front, w_front);

                /* Since we can't estimate the cost of cloning a vehicle accurately we must
                 * check whether the company has enough money manually. */
                if (!CheckCompanyHasMoney(total_cost)) {
                        /* The vehicle has already been bought, so now it must be sold again. */
                        Command<CMD_SELL_VEHICLE>::Do(flags, w_front->index, true, false, INVALID_CLIENT_ID);
                        return { total_cost, INVALID_VEHICLE };
                }
        }

        return { total_cost, new_veh_id };
}

/**
 * Send all vehicles of type to depots
 * @param flags   the flags used for DoCommand()
 * @param service should the vehicles only get service in the depots
 * @param vli     identifier of the vehicle list
 * @return 0 for success and CMD_ERROR if no vehicle is able to go to depot
 */
static CommandCost SendAllVehiclesToDepot(DoCommandFlag flags, bool service, const VehicleListIdentifier &vli)
{
        VehicleList list;

        if (!GenerateVehicleSortList(&list, vli)) return CMD_ERROR;

        /* Send all the vehicles to a depot */
        bool had_success = false;
        for (uint i = 0; i < list.size(); i++) {
                const Vehicle *v = list[i];
                CommandCost ret = Command<CMD_SEND_VEHICLE_TO_DEPOT>::Do(flags, v->index, (service ? DepotCommand::Service : DepotCommand::None) | DepotCommand::DontCancel, {});

                if (ret.Succeeded()) {
                        had_success = true;

                        /* Return 0 if DC_EXEC is not set this is a valid goto depot command)
                         * In this case we know that at least one vehicle can be sent to a depot
                         * and we will issue the command. We can now safely quit the loop, knowing
                         * it will succeed at least once. With DC_EXEC we really need to send them to the depot */
                        if (!(flags & DC_EXEC)) break;
                }
        }

        return had_success ? CommandCost() : CMD_ERROR;
}

/**
 * Send a vehicle to the depot.
 * @param flags for command type
 * @param veh_id vehicle ID to send to the depot
 * @param depot_cmd DEPOT_ flags (see vehicle_type.h)
 * @param vli VehicleListIdentifier.
 * @return the cost of this operation or an error
 */
CommandCost CmdSendVehicleToDepot(DoCommandFlag flags, VehicleID veh_id, DepotCommand depot_cmd, const VehicleListIdentifier &vli)
{
        if ((depot_cmd & DepotCommand::MassSend) != DepotCommand::None) {
                /* Mass goto depot requested */
                if (!vli.Valid()) return CMD_ERROR;
                return SendAllVehiclesToDepot(flags, (depot_cmd & DepotCommand::Service) != DepotCommand::None, vli);
        }

        Vehicle *v = Vehicle::GetIfValid(veh_id);
        if (v == nullptr) return CMD_ERROR;
        if (!v->IsPrimaryVehicle()) return CMD_ERROR;

        return v->SendToDepot(flags, depot_cmd);
}

/**
 * Give a custom name to your vehicle
 * @param flags type of operation
 * @param veh_id vehicle ID to name
 * @param text the new name or an empty string when resetting to the default
 * @return the cost of this operation or an error
 */
CommandCost CmdRenameVehicle(DoCommandFlag flags, VehicleID veh_id, const std::string &text)
{
        Vehicle *v = Vehicle::GetIfValid(veh_id);
        if (v == nullptr || !v->IsPrimaryVehicle()) return CMD_ERROR;

        CommandCost ret = CheckOwnership(v->owner);
        if (ret.Failed()) return ret;

        bool reset = text.empty();

        if (!reset) {
                if (Utf8StringLength(text) >= MAX_LENGTH_VEHICLE_NAME_CHARS) return CMD_ERROR;
                if (!(flags & DC_AUTOREPLACE) && !IsUniqueVehicleName(text)) return_cmd_error(STR_ERROR_NAME_MUST_BE_UNIQUE);
        }

        if (flags & DC_EXEC) {
                if (reset) {
                        v->name.clear();
                } else {
                        v->name = text;
                }
                InvalidateWindowClassesData(GetWindowClassForVehicleType(v->type), 1);
                MarkWholeScreenDirty();
        }

        return CommandCost();
}


/**
 * Change the service interval of a vehicle
 * @param flags type of operation
 * @param veh_id vehicle ID that is being service-interval-changed
 * @param serv_int new service interval
 * @param is_custom service interval is custom flag
 * @param is_percent service interval is percentage flag
 * @return the cost of this operation or an error
 */
CommandCost CmdChangeServiceInt(DoCommandFlag flags, VehicleID veh_id, uint16 serv_int, bool is_custom, bool is_percent)
{
        Vehicle *v = Vehicle::GetIfValid(veh_id);
        if (v == nullptr || !v->IsPrimaryVehicle()) return CMD_ERROR;

        CommandCost ret = CheckOwnership(v->owner);
        if (ret.Failed()) return ret;

        const Company *company = Company::Get(v->owner);
        is_percent = is_custom ? is_percent : company->settings.vehicle.servint_ispercent;

        if (is_custom) {
                if (serv_int != GetServiceIntervalClamped(serv_int, is_percent)) return CMD_ERROR;
        } else {
                serv_int = CompanyServiceInterval(company, v->type);
        }

        if (flags & DC_EXEC) {
                v->SetServiceInterval(serv_int);
                v->SetServiceIntervalIsCustom(is_custom);
                v->SetServiceIntervalIsPercent(is_percent);
                SetWindowDirty(WC_VEHICLE_DETAILS, v->index);
        }

        return CommandCost();
}