# autoreplace_cmd.cpp

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    00001 /* $Id$ */
    00002
    00003 /*
    00004  * This file is part of OpenTTD.
    00005  * 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.
    00006  * 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.
    00007  * 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/>.
    00008  */
    00009
    00012 #include "stdafx.h"
    00013 #include "company_func.h"
    00014 #include "train.h"
    00015 #include "command_func.h"
    00016 #include "engine_func.h"
    00017 #include "vehicle_func.h"
    00018 #include "autoreplace_func.h"
    00019 #include "autoreplace_gui.h"
    00020 #include "group.h"
    00021 #include "articulated_vehicles.h"
    00022 #include "core/random_func.hpp"
    00023
    00024 #include "table/strings.h"
    00025
    00026 extern void ChangeVehicleViewports(VehicleID from_index, VehicleID to_index);
    00027 extern void ChangeVehicleNews(VehicleID from_index, VehicleID to_index);
    00028 extern void ChangeVehicleViewWindow(VehicleID from_index, VehicleID to_index);
    00029
    00037 static bool EnginesHaveCargoInCommon(EngineID engine_a, EngineID engine_b)
    00038 {
    00039   uint32 available_cargos_a = GetUnionOfArticulatedRefitMasks(engine_a, true);
    00040   uint32 available_cargos_b = GetUnionOfArticulatedRefitMasks(engine_b, true);
    00041   return (available_cargos_a == 0 || available_cargos_b == 0 || (available_cargos_a & available_cargos_b) != 0);
    00042 }
    00043
    00051 bool CheckAutoreplaceValidity(EngineID from, EngineID to, CompanyID company)
    00052 {
    00053   assert(Engine::IsValidID(from) && Engine::IsValidID(to));
    00054
    00055   /* we can't replace an engine into itself (that would be autorenew) */
    00056   if (from == to) return false;
    00057
    00058   const Engine *e_from = Engine::Get(from);
    00059   const Engine *e_to = Engine::Get(to);
    00060   VehicleType type = e_from->type;
    00061
    00062   /* check that the new vehicle type is available to the company and its type is the same as the original one */
    00063   if (!IsEngineBuildable(to, type, company)) return false;
    00064
    00065   switch (type) {
    00066     case VEH_TRAIN: {
    00067       /* make sure the railtypes are compatible */
    00068       if ((GetRailTypeInfo(e_from->u.rail.railtype)->compatible_railtypes & GetRailTypeInfo(e_to->u.rail.railtype)->compatible_railtypes) == 0) return false;
    00069
    00070       /* make sure we do not replace wagons with engines or vise versa */
    00071       if ((e_from->u.rail.railveh_type == RAILVEH_WAGON) != (e_to->u.rail.railveh_type == RAILVEH_WAGON)) return false;
    00072       break;
    00073     }
    00074
    00075     case VEH_ROAD:
    00076       /* make sure that we do not replace a tram with a normal road vehicles or vise versa */
    00077       if (HasBit(e_from->info.misc_flags, EF_ROAD_TRAM) != HasBit(e_to->info.misc_flags, EF_ROAD_TRAM)) return false;
    00078       break;
    00079
    00080     case VEH_AIRCRAFT:
    00081       /* make sure that we do not replace a plane with a helicopter or vise versa */
    00082       if ((e_from->u.air.subtype & AIR_CTOL) != (e_to->u.air.subtype & AIR_CTOL)) return false;
    00083       break;
    00084
    00085     default: break;
    00086   }
    00087
    00088   /* the engines needs to be able to carry the same cargo */
    00089   return EnginesHaveCargoInCommon(from, to);
    00090 }
    00091
    00098 static void TransferCargo(Vehicle *old_veh, Vehicle *new_head, bool part_of_chain)
    00099 {
    00100   assert(!part_of_chain || new_head->IsPrimaryVehicle());
    00101   /* Loop through source parts */
    00102   for (Vehicle *src = old_veh; src != NULL; src = src->Next()) {
    00103     if (!part_of_chain && src->type == VEH_TRAIN && src != old_veh && src != Train::From(old_veh)->other_multiheaded_part && !src->IsArticulatedPart()) {
    00104       /* Skip vehicles, which do not belong to old_veh */
    00105       src = src->GetLastEnginePart();
    00106       continue;
    00107     }
    00108     if (src->cargo_type >= NUM_CARGO || src->cargo.Count() == 0) continue;
    00109
    00110     /* Find free space in the new chain */
    00111     for (Vehicle *dest = new_head; dest != NULL && src->cargo.Count() > 0; dest = dest->Next()) {
    00112       if (!part_of_chain && dest->type == VEH_TRAIN && dest != new_head && dest != Train::From(new_head)->other_multiheaded_part && !dest->IsArticulatedPart()) {
    00113         /* Skip vehicles, which do not belong to new_head */
    00114         dest = dest->GetLastEnginePart();
    00115         continue;
    00116       }
    00117       if (dest->cargo_type != src->cargo_type) continue;
    00118
    00119       uint amount = min(src->cargo.Count(), dest->cargo_cap - dest->cargo.Count());
    00120       if (amount <= 0) continue;
    00121
    00122       src->cargo.MoveTo(&dest->cargo, amount, VehicleCargoList::MTA_UNLOAD, NULL);
    00123     }
    00124   }
    00125
    00126   /* Update train weight etc., the old vehicle will be sold anyway */
    00127   if (part_of_chain && new_head->type == VEH_TRAIN) Train::From(new_head)->ConsistChanged(true);
    00128 }
    00129
    00136 static bool VerifyAutoreplaceRefitForOrders(const Vehicle *v, EngineID engine_type)
    00137 {
    00138
    00139   uint32 union_refit_mask_a = GetUnionOfArticulatedRefitMasks(v->engine_type, false);
    00140   uint32 union_refit_mask_b = GetUnionOfArticulatedRefitMasks(engine_type, false);
    00141
    00142   const Order *o;
    00143   const Vehicle *u = (v->type == VEH_TRAIN) ? v->First() : v;
    00144   FOR_VEHICLE_ORDERS(u, o) {
    00145     if (!o->IsRefit()) continue;
    00146     CargoID cargo_type = o->GetRefitCargo();
    00147
    00148     if (!HasBit(union_refit_mask_a, cargo_type)) continue;
    00149     if (!HasBit(union_refit_mask_b, cargo_type)) return false;
    00150   }
    00151
    00152   return true;
    00153 }
    00154
    00164 static CargoID GetNewCargoTypeForReplace(Vehicle *v, EngineID engine_type, bool part_of_chain)
    00165 {
    00166   uint32 available_cargo_types, union_mask;
    00167   GetArticulatedRefitMasks(engine_type, true, &union_mask, &available_cargo_types);
    00168
    00169   if (union_mask == 0) return CT_NO_REFIT; // Don't try to refit an engine with no cargo capacity
    00170
    00171   CargoID cargo_type;
    00172   if (IsArticulatedVehicleCarryingDifferentCargos(v, &cargo_type)) return CT_INVALID; // We cannot refit to mixed cargos in an automated way
    00173
    00174   if (cargo_type == CT_INVALID) {
    00175     if (v->type != VEH_TRAIN) return CT_NO_REFIT; // If the vehicle does not carry anything at all, every replacement is fine.
    00176
    00177     if (!part_of_chain) return CT_NO_REFIT;
    00178
    00179     /* the old engine didn't have cargo capacity, but the new one does
    00180      * now we will figure out what cargo the train is carrying and refit to fit this */
    00181
    00182     for (v = v->First(); v != NULL; v = v->Next()) {
    00183       if (v->cargo_cap == 0) continue;
    00184       /* Now we found a cargo type being carried on the train and we will see if it is possible to carry to this one */
    00185       if (HasBit(available_cargo_types, v->cargo_type)) {
    00186         /* Do we have to refit the vehicle, or is it already carrying the right cargo? */
    00187         CargoArray default_capacity = GetCapacityOfArticulatedParts(engine_type);
    00188         for (CargoID cid = 0; cid < NUM_CARGO; cid++) {
    00189           if (cid != v->cargo_type && default_capacity[cid] > 0) return v->cargo_type;
    00190         }
    00191
    00192         return CT_NO_REFIT;
    00193       }
    00194     }
    00195
    00196     return CT_NO_REFIT; // We failed to find a cargo type on the old vehicle and we will not refit the new one
    00197   } else {
    00198     if (!HasBit(available_cargo_types, cargo_type)) return CT_INVALID; // We can't refit the vehicle to carry the cargo we want
    00199
    00200     if (part_of_chain && !VerifyAutoreplaceRefitForOrders(v, engine_type)) return CT_INVALID; // Some refit orders lose their effect
    00201
    00202     /* Do we have to refit the vehicle, or is it already carrying the right cargo? */
    00203     CargoArray default_capacity = GetCapacityOfArticulatedParts(engine_type);
    00204     for (CargoID cid = 0; cid < NUM_CARGO; cid++) {
    00205       if (cid != cargo_type && default_capacity[cid] > 0) return cargo_type;
    00206     }
    00207
    00208     return CT_NO_REFIT;
    00209   }
    00210 }
    00211
    00218 static EngineID GetNewEngineType(const Vehicle *v, const Company *c)
    00219 {
    00220   assert(v->type != VEH_TRAIN || !v->IsArticulatedPart());
    00221
    00222   if (v->type == VEH_TRAIN && Train::From(v)->IsRearDualheaded()) {
    00223     /* we build the rear ends of multiheaded trains with the front ones */
    00224     return INVALID_ENGINE;
    00225   }
    00226
    00227   EngineID e = EngineReplacementForCompany(c, v->engine_type, v->group_id);
    00228
    00229   if (e != INVALID_ENGINE && IsEngineBuildable(e, v->type, _current_company)) {
    00230     return e;
    00231   }
    00232
    00233   if (v->NeedsAutorenewing(c) && // replace if engine is too old
    00234       IsEngineBuildable(v->engine_type, v->type, _current_company)) { // engine can still be build
    00235     return v->engine_type;
    00236   }
    00237
    00238   return INVALID_ENGINE;
    00239 }
    00240
    00249 static CommandCost BuildReplacementVehicle(Vehicle *old_veh, Vehicle **new_vehicle, bool part_of_chain)
    00250 {
    00251   *new_vehicle = NULL;
    00252
    00253   /* Shall the vehicle be replaced? */
    00254   const Company *c = Company::Get(_current_company);
    00255   EngineID e = GetNewEngineType(old_veh, c);
    00256   if (e == INVALID_ENGINE) return CommandCost(); // neither autoreplace is set, nor autorenew is triggered
    00257
    00258   /* Does it need to be refitted */
    00259   CargoID refit_cargo = GetNewCargoTypeForReplace(old_veh, e, part_of_chain);
    00260   if (refit_cargo == CT_INVALID) return CommandCost(); // incompatible cargos
    00261
    00262   /* Build the new vehicle */
    00263   CommandCost cost = DoCommand(old_veh->tile, e, 0, DC_EXEC | DC_AUTOREPLACE, GetCmdBuildVeh(old_veh));
    00264   if (cost.Failed()) return cost;
    00265
    00266   Vehicle *new_veh = Vehicle::Get(_new_vehicle_id);
    00267   *new_vehicle = new_veh;
    00268
    00269   /* Refit the vehicle if needed */
    00270   byte subtype = GetBestFittingSubType(old_veh, new_veh);
    00271   /* If the subtype isn't zero and the refit cargo is not set,
    00272    * we're better off setting the refit cargo too. */
    00273   if (subtype != 0 && refit_cargo == CT_NO_REFIT) refit_cargo = old_veh->cargo_type;
    00274
    00275   if (refit_cargo != CT_NO_REFIT) {
    00276     cost.AddCost(DoCommand(0, new_veh->index, refit_cargo | (subtype << 8), DC_EXEC, GetCmdRefitVeh(new_veh)));
    00277     assert(cost.Succeeded()); // This should be ensured by GetNewCargoTypeForReplace()
    00278   }
    00279
    00280   /* Try to reverse the vehicle, but do not care if it fails as the new type might not be reversible */
    00281   if (new_veh->type == VEH_TRAIN && HasBit(Train::From(old_veh)->flags, VRF_REVERSE_DIRECTION)) {
    00282     DoCommand(0, new_veh->index, true, DC_EXEC, CMD_REVERSE_TRAIN_DIRECTION);
    00283   }
    00284
    00285   return cost;
    00286 }
    00287
    00294 static inline CommandCost CmdStartStopVehicle(const Vehicle *v, bool evaluate_callback)
    00295 {
    00296   return DoCommand(0, v->index, evaluate_callback ? 1 : 0, DC_EXEC | DC_AUTOREPLACE, CMD_START_STOP_VEHICLE);
    00297 }
    00298
    00307 static inline CommandCost CmdMoveVehicle(const Vehicle *v, const Vehicle *after, DoCommandFlag flags, bool whole_chain)
    00308 {
    00309   return DoCommand(0, v->index | (whole_chain ? 1 : 0) << 20, after != NULL ? after->index : INVALID_VEHICLE, flags, CMD_MOVE_RAIL_VEHICLE);
    00310 }
    00311
    00318 static CommandCost CopyHeadSpecificThings(Vehicle *old_head, Vehicle *new_head, DoCommandFlag flags)
    00319 {
    00320   CommandCost cost = CommandCost();
    00321
    00322   /* Share orders */
    00323   if (cost.Succeeded() && old_head != new_head) cost.AddCost(DoCommand(0, new_head->index | CO_SHARE << 30, old_head->index, DC_EXEC, CMD_CLONE_ORDER));
    00324
    00325   /* Copy group membership */
    00326   if (cost.Succeeded() && old_head != new_head) cost.AddCost(DoCommand(0, old_head->group_id, new_head->index, DC_EXEC, CMD_ADD_VEHICLE_GROUP));
    00327
    00328   /* Perform start/stop check whether the new vehicle suits newgrf restrictions etc. */
    00329   if (cost.Succeeded()) {
    00330     /* Start the vehicle, might be denied by certain things */
    00331     assert((new_head->vehstatus & VS_STOPPED) != 0);
    00332     cost.AddCost(CmdStartStopVehicle(new_head, true));
    00333
    00334     /* Stop the vehicle again, but do not care about evil newgrfs allowing starting but not stopping :p */
    00335     if (cost.Succeeded()) cost.AddCost(CmdStartStopVehicle(new_head, false));
    00336   }
    00337
    00338   /* Last do those things which do never fail (resp. we do not care about), but which are not undo-able */
    00339   if (cost.Succeeded() && old_head != new_head && (flags & DC_EXEC) != 0) {
    00340     /* Copy vehicle name */
    00341     if (old_head->name != NULL) {
    00342       DoCommand(0, new_head->index, 0, DC_EXEC | DC_AUTOREPLACE, CMD_RENAME_VEHICLE, old_head->name);
    00343     }
    00344
    00345     /* Copy other things which cannot be copied by a command and which shall not stay resetted from the build vehicle command */
    00346     new_head->CopyVehicleConfigAndStatistics(old_head);
    00347
    00348     /* Switch vehicle windows/news to the new vehicle, so they are not closed/deleted when the old vehicle is sold */
    00349     ChangeVehicleViewports(old_head->index, new_head->index);
    00350     ChangeVehicleViewWindow(old_head->index, new_head->index);
    00351     ChangeVehicleNews(old_head->index, new_head->index);
    00352   }
    00353
    00354   return cost;
    00355 }
    00356
    00364 static CommandCost ReplaceFreeUnit(Vehicle **single_unit, DoCommandFlag flags, bool *nothing_to_do)
    00365 {
    00366   Train *old_v = Train::From(*single_unit);
    00367   assert(!old_v->IsArticulatedPart() && !old_v->IsRearDualheaded());
    00368
    00369   CommandCost cost = CommandCost(EXPENSES_NEW_VEHICLES, 0);
    00370
    00371   /* Build and refit replacement vehicle */
    00372   Vehicle *new_v = NULL;
    00373   cost.AddCost(BuildReplacementVehicle(old_v, &new_v, false));
    00374
    00375   /* Was a new vehicle constructed? */
    00376   if (cost.Succeeded() && new_v != NULL) {
    00377     *nothing_to_do = false;
    00378
    00379     if ((flags & DC_EXEC) != 0) {
    00380       /* Move the new vehicle behind the old */
    00381       CmdMoveVehicle(new_v, old_v, DC_EXEC, false);
    00382
    00383       /* Take over cargo
    00384        * Note: We do only transfer cargo from the old to the new vehicle.
    00385        *       I.e. we do not transfer remaining cargo to other vehicles.
    00386        *       Else you would also need to consider moving cargo to other free chains,
    00387        *       or doing the same in ReplaceChain(), which would be quite troublesome.
    00388        */
    00389       TransferCargo(old_v, new_v, false);
    00390
    00391       *single_unit = new_v;
    00392     }
    00393
    00394     /* Sell the old vehicle */
    00395     cost.AddCost(DoCommand(0, old_v->index, 0, flags, GetCmdSellVeh(old_v)));
    00396
    00397     /* If we are not in DC_EXEC undo everything */
    00398     if ((flags & DC_EXEC) == 0) {
    00399       DoCommand(0, new_v->index, 0, DC_EXEC, GetCmdSellVeh(new_v));
    00400     }
    00401   }
    00402
    00403   return cost;
    00404 }
    00405
    00414 static CommandCost ReplaceChain(Vehicle **chain, DoCommandFlag flags, bool wagon_removal, bool *nothing_to_do)
    00415 {
    00416   Vehicle *old_head = *chain;
    00417   assert(old_head->IsPrimaryVehicle());
    00418
    00419   CommandCost cost = CommandCost(EXPENSES_NEW_VEHICLES, 0);
    00420
    00421   if (old_head->type == VEH_TRAIN) {
    00422     /* Store the length of the old vehicle chain, rounded up to whole tiles */
    00423     uint16 old_total_length = CeilDiv(Train::From(old_head)->gcache.cached_total_length, TILE_SIZE) * TILE_SIZE;
    00424
    00425     int num_units = 0;
    00426     for (Train *w = Train::From(old_head); w != NULL; w = w->GetNextUnit()) num_units++;
    00427
    00428     Train **old_vehs = CallocT<Train *>(num_units);
    00429     Train **new_vehs = CallocT<Train *>(num_units);
    00430     Money *new_costs = MallocT<Money>(num_units);
    00431
    00432     /* Collect vehicles and build replacements
    00433      * Note: The replacement vehicles can only successfully build as long as the old vehicles are still in their chain */
    00434     int i;
    00435     Train *w;
    00436     for (w = Train::From(old_head), i = 0; w != NULL; w = w->GetNextUnit(), i++) {
    00437       assert(i < num_units);
    00438       old_vehs[i] = w;
    00439
    00440       CommandCost ret = BuildReplacementVehicle(old_vehs[i], (Vehicle**)&new_vehs[i], true);
    00441       cost.AddCost(ret);
    00442       if (cost.Failed()) break;
    00443
    00444       new_costs[i] = ret.GetCost();
    00445       if (new_vehs[i] != NULL) *nothing_to_do = false;
    00446     }
    00447     Train *new_head = (new_vehs[0] != NULL ? new_vehs[0] : old_vehs[0]);
    00448
    00449     /* Note: When autoreplace has already failed here, old_vehs[] is not completely initialized. But it is also not needed. */
    00450     if (cost.Succeeded()) {
    00451       /* Separate the head, so we can start constructing the new chain */
    00452       Train *second = Train::From(old_head)->GetNextUnit();
    00453       if (second != NULL) cost.AddCost(CmdMoveVehicle(second, NULL, DC_EXEC | DC_AUTOREPLACE, true));
    00454
    00455       assert(Train::From(new_head)->GetNextUnit() == NULL);
    00456
    00457       /* Append engines to the new chain
    00458        * We do this from back to front, so that the head of the temporary vehicle chain does not change all the time.
    00459        * That way we also have less trouble when exceeding the unitnumber limit.
    00460        * OTOH the vehicle attach callback is more expensive this way :s */
    00461       Train *last_engine = NULL;
    00462       if (cost.Succeeded()) {
    00463         for (int i = num_units - 1; i > 0; i--) {
    00464           Train *append = (new_vehs[i] != NULL ? new_vehs[i] : old_vehs[i]);
    00465
    00466           if (RailVehInfo(append->engine_type)->railveh_type == RAILVEH_WAGON) continue;
    00467
    00468           if (new_vehs[i] != NULL) {
    00469             /* Move the old engine to a separate row with DC_AUTOREPLACE. Else
    00470              * moving the wagon in front may fail later due to unitnumber limit.
    00471              * (We have to attach wagons without DC_AUTOREPLACE.) */
    00472             CmdMoveVehicle(old_vehs[i], NULL, DC_EXEC | DC_AUTOREPLACE, false);
    00473           }
    00474
    00475           if (last_engine == NULL) last_engine = append;
    00476           cost.AddCost(CmdMoveVehicle(append, new_head, DC_EXEC, false));
    00477           if (cost.Failed()) break;
    00478         }
    00479         if (last_engine == NULL) last_engine = new_head;
    00480       }
    00481
    00482       /* When wagon removal is enabled and the new engines without any wagons are already longer than the old, we have to fail */
    00483       if (cost.Succeeded() && wagon_removal && new_head->gcache.cached_total_length > old_total_length) cost = CommandCost(STR_ERROR_TRAIN_TOO_LONG_AFTER_REPLACEMENT);
    00484
    00485       /* Append/insert wagons into the new vehicle chain
    00486        * We do this from back to front, so we can stop when wagon removal or maximum train length (i.e. from mammoth-train setting) is triggered.
    00487        */
    00488       if (cost.Succeeded()) {
    00489         for (int i = num_units - 1; i > 0; i--) {
    00490           assert(last_engine != NULL);
    00491           Vehicle *append = (new_vehs[i] != NULL ? new_vehs[i] : old_vehs[i]);
    00492
    00493           if (RailVehInfo(append->engine_type)->railveh_type == RAILVEH_WAGON) {
    00494             /* Insert wagon after 'last_engine' */
    00495             CommandCost res = CmdMoveVehicle(append, last_engine, DC_EXEC, false);
    00496
    00497             /* When we allow removal of wagons, either the move failing due
    00498              * to the train becoming too long, or the train becoming longer
    00499              * would move the vehicle to the empty vehicle chain. */
    00500             if (wagon_removal && (res.Failed() ? res.GetErrorMessage() == STR_ERROR_TRAIN_TOO_LONG : new_head->gcache.cached_total_length > old_total_length)) {
    00501               CmdMoveVehicle(append, NULL, DC_EXEC | DC_AUTOREPLACE, false);
    00502               break;
    00503             }
    00504
    00505             cost.AddCost(res);
    00506             if (cost.Failed()) break;
    00507           } else {
    00508             /* We have reached 'last_engine', continue with the next engine towards the front */
    00509             assert(append == last_engine);
    00510             last_engine = last_engine->GetPrevUnit();
    00511           }
    00512         }
    00513       }
    00514
    00515       /* Sell superfluous new vehicles that could not be inserted. */
    00516       if (cost.Succeeded() && wagon_removal) {
    00517         assert(new_head->gcache.cached_total_length <= _settings_game.vehicle.max_train_length * TILE_SIZE);
    00518         for (int i = 1; i < num_units; i++) {
    00519           Vehicle *wagon = new_vehs[i];
    00520           if (wagon == NULL) continue;
    00521           if (wagon->First() == new_head) break;
    00522
    00523           assert(RailVehInfo(wagon->engine_type)->railveh_type == RAILVEH_WAGON);
    00524
    00525           /* Sell wagon */
    00526           CommandCost ret = DoCommand(0, wagon->index, 0, DC_EXEC, GetCmdSellVeh(wagon));
    00527           assert(ret.Succeeded());
    00528           new_vehs[i] = NULL;
    00529
    00530           /* Revert the money subtraction when the vehicle was built.
    00531            * This value is different from the sell value, esp. because of refitting */
    00532           cost.AddCost(-new_costs[i]);
    00533         }
    00534       }
    00535
    00536       /* The new vehicle chain is constructed, now take over orders and everything... */
    00537       if (cost.Succeeded()) cost.AddCost(CopyHeadSpecificThings(old_head, new_head, flags));
    00538
    00539       if (cost.Succeeded()) {
    00540         /* Success ! */
    00541         if ((flags & DC_EXEC) != 0 && new_head != old_head) {
    00542           *chain = new_head;
    00543         }
    00544
    00545         /* Transfer cargo of old vehicles and sell them */
    00546         for (int i = 0; i < num_units; i++) {
    00547           Vehicle *w = old_vehs[i];
    00548           /* Is the vehicle again part of the new chain?
    00549            * Note: We cannot test 'new_vehs[i] != NULL' as wagon removal might cause to remove both */
    00550           if (w->First() == new_head) continue;
    00551
    00552           if ((flags & DC_EXEC) != 0) TransferCargo(w, new_head, true);
    00553
    00554           /* Sell the vehicle.
    00555            * Note: This might temporarly construct new trains, so use DC_AUTOREPLACE to prevent
    00556            *       it from failing due to engine limits. */
    00557           cost.AddCost(DoCommand(0, w->index, 0, flags | DC_AUTOREPLACE, GetCmdSellVeh(w)));
    00558           if ((flags & DC_EXEC) != 0) {
    00559             old_vehs[i] = NULL;
    00560             if (i == 0) old_head = NULL;
    00561           }
    00562         }
    00563       }
    00564
    00565       /* If we are not in DC_EXEC undo everything, i.e. rearrange old vehicles.
    00566        * We do this from back to front, so that the head of the temporary vehicle chain does not change all the time.
    00567        * Note: The vehicle attach callback is disabled here :) */
    00568       if ((flags & DC_EXEC) == 0) {
    00569         /* Separate the head, so we can reattach the old vehicles */
    00570         Train *second = Train::From(old_head)->GetNextUnit();
    00571         if (second != NULL) CmdMoveVehicle(second, NULL, DC_EXEC | DC_AUTOREPLACE, true);
    00572
    00573         assert(Train::From(old_head)->GetNextUnit() == NULL);
    00574
    00575         for (int i = num_units - 1; i > 0; i--) {
    00576           CommandCost ret = CmdMoveVehicle(old_vehs[i], old_head, DC_EXEC | DC_AUTOREPLACE, false);
    00577           assert(ret.Succeeded());
    00578         }
    00579       }
    00580     }
    00581
    00582     /* Finally undo buying of new vehicles */
    00583     if ((flags & DC_EXEC) == 0) {
    00584       for (int i = num_units - 1; i >= 0; i--) {
    00585         if (new_vehs[i] != NULL) {
    00586           DoCommand(0, new_vehs[i]->index, 0, DC_EXEC, GetCmdSellVeh(new_vehs[i]));
    00587           new_vehs[i] = NULL;
    00588         }
    00589       }
    00590     }
    00591
    00592     free(old_vehs);
    00593     free(new_vehs);
    00594     free(new_costs);
    00595   } else {
    00596     /* Build and refit replacement vehicle */
    00597     Vehicle *new_head = NULL;
    00598     cost.AddCost(BuildReplacementVehicle(old_head, &new_head, true));
    00599
    00600     /* Was a new vehicle constructed? */
    00601     if (cost.Succeeded() && new_head != NULL) {
    00602       *nothing_to_do = false;
    00603
    00604       /* The new vehicle is constructed, now take over orders and everything... */
    00605       cost.AddCost(CopyHeadSpecificThings(old_head, new_head, flags));
    00606
    00607       if (cost.Succeeded()) {
    00608         /* The new vehicle is constructed, now take over cargo */
    00609         if ((flags & DC_EXEC) != 0) {
    00610           TransferCargo(old_head, new_head, true);
    00611           *chain = new_head;
    00612         }
    00613
    00614         /* Sell the old vehicle */
    00615         cost.AddCost(DoCommand(0, old_head->index, 0, flags, GetCmdSellVeh(old_head)));
    00616       }
    00617
    00618       /* If we are not in DC_EXEC undo everything */
    00619       if ((flags & DC_EXEC) == 0) {
    00620         DoCommand(0, new_head->index, 0, DC_EXEC, GetCmdSellVeh(new_head));
    00621       }
    00622     }
    00623   }
    00624
    00625   return cost;
    00626 }
    00627
    00638 CommandCost CmdAutoreplaceVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
    00639 {
    00640   Vehicle *v = Vehicle::GetIfValid(p1);
    00641   if (v == NULL) return CMD_ERROR;
    00642
    00643   CommandCost ret = CheckOwnership(v->owner);
    00644   if (ret.Failed()) return ret;
    00645
    00646   if (!v->IsInDepot()) return CMD_ERROR;
    00647   if (v->vehstatus & VS_CRASHED) return CMD_ERROR;
    00648
    00649   bool free_wagon = false;
    00650   if (v->type == VEH_TRAIN) {
    00651     Train *t = Train::From(v);
    00652     if (t->IsArticulatedPart() || t->IsRearDualheaded()) return CMD_ERROR;
    00653     free_wagon = !t->IsFrontEngine();
    00654     if (free_wagon && t->First()->IsFrontEngine()) return CMD_ERROR;
    00655   } else {
    00656     if (!v->IsPrimaryVehicle()) return CMD_ERROR;
    00657   }
    00658
    00659   const Company *c = Company::Get(_current_company);
    00660   bool wagon_removal = c->settings.renew_keep_length;
    00661
    00662   /* Test whether any replacement is set, before issuing a whole lot of commands that would end in nothing changed */
    00663   Vehicle *w = v;
    00664   bool any_replacements = false;
    00665   while (w != NULL && !any_replacements) {
    00666     any_replacements = (GetNewEngineType(w, c) != INVALID_ENGINE);
    00667     w = (!free_wagon && w->type == VEH_TRAIN ? Train::From(w)->GetNextUnit() : NULL);
    00668   }
    00669
    00670   CommandCost cost = CommandCost(EXPENSES_NEW_VEHICLES, 0);
    00671   bool nothing_to_do = true;
    00672
    00673   if (any_replacements) {
    00674     bool was_stopped = free_wagon || ((v->vehstatus & VS_STOPPED) != 0);
    00675
    00676     /* Stop the vehicle */
    00677     if (!was_stopped) cost.AddCost(CmdStartStopVehicle(v, true));
    00678     if (cost.Failed()) return cost;
    00679
    00680     assert(v->IsStoppedInDepot());
    00681
    00682     /* We have to construct the new vehicle chain to test whether it is valid.
    00683      * Vehicle construction needs random bits, so we have to save the random seeds
    00684      * to prevent desyncs and to replay newgrf callbacks during DC_EXEC */
    00685     SavedRandomSeeds saved_seeds;
    00686     SaveRandomSeeds(&saved_seeds);
    00687     if (free_wagon) {
    00688       cost.AddCost(ReplaceFreeUnit(&v, flags & ~DC_EXEC, &nothing_to_do));
    00689     } else {
    00690       cost.AddCost(ReplaceChain(&v, flags & ~DC_EXEC, wagon_removal, &nothing_to_do));
    00691     }
    00692     RestoreRandomSeeds(saved_seeds);
    00693
    00694     if (cost.Succeeded() && (flags & DC_EXEC) != 0) {
    00695       CommandCost ret;
    00696       if (free_wagon) {
    00697         ret = ReplaceFreeUnit(&v, flags, &nothing_to_do);
    00698       } else {
    00699         ret = ReplaceChain(&v, flags, wagon_removal, &nothing_to_do);
    00700       }
    00701       assert(ret.Succeeded() && ret.GetCost() == cost.GetCost());
    00702     }
    00703
    00704     /* Restart the vehicle */
    00705     if (!was_stopped) cost.AddCost(CmdStartStopVehicle(v, false));
    00706   }
    00707
    00708   if (cost.Succeeded() && nothing_to_do) cost = CommandCost(STR_ERROR_AUTOREPLACE_NOTHING_TO_DO);
    00709   return cost;
    00710 }
    00711
    00724 CommandCost CmdSetAutoReplace(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
    00725 {
    00726   Company *c = Company::GetIfValid(_current_company);
    00727   if (c == NULL) return CMD_ERROR;
    00728
    00729   EngineID old_engine_type = GB(p2, 0, 16);
    00730   EngineID new_engine_type = GB(p2, 16, 16);
    00731   GroupID id_g = GB(p1, 16, 16);
    00732   CommandCost cost;
    00733
    00734   if (!Group::IsValidID(id_g) && !IsAllGroupID(id_g) && !IsDefaultGroupID(id_g)) return CMD_ERROR;
    00735   if (!Engine::IsValidID(old_engine_type)) return CMD_ERROR;
    00736
    00737   if (new_engine_type != INVALID_ENGINE) {
    00738     if (!Engine::IsValidID(new_engine_type)) return CMD_ERROR;
    00739     if (!CheckAutoreplaceValidity(old_engine_type, new_engine_type, _current_company)) return CMD_ERROR;
    00740
    00741     cost = AddEngineReplacementForCompany(c, old_engine_type, new_engine_type, id_g, flags);
    00742   } else {
    00743     cost = RemoveEngineReplacementForCompany(c, old_engine_type, id_g, flags);
    00744   }
    00745
    00746   if ((flags & DC_EXEC) && IsLocalCompany()) InvalidateAutoreplaceWindow(old_engine_type, id_g);
    00747
    00748   return cost;
    00749 }
    00750