91 /*

    92  * move the cargo from one engine to another if possible

    93  */

    94 static void MoveVehicleCargo(Vehicle *dest, Vehicle *source)

    95 {

    96 	Vehicle *v = dest;

    97 

    98 	do {

    99 		do {

   100 			if (source->cargo_type != dest->cargo_type)

   101 				continue; // cargo not compatible

   102 

   103 			if (dest->cargo.Count() == dest->cargo_cap)

   104 				continue; // the destination vehicle is already full

   105 

   106 			uint units_moved = min(source->cargo.Count(), dest->cargo_cap - dest->cargo.Count());

   107 			source->cargo.MoveTo(&dest->cargo, units_moved);

   108 

   109 			// copy the age of the cargo

   110 			dest->day_counter  = source->day_counter;

   111 			dest->tick_counter = source->tick_counter;

   112 

   113 		} while (source->cargo.Count() > 0 && (dest = dest->Next()) != NULL);

   114 		dest = v;

   115 	} while ((source = source->Next()) != NULL);

   116 

   117 	/*

   118 	 * The of the train will be incorrect at this moment. This is due

   119 	 * to the fact that removing the old wagon updates the weight of

   120 	 * the complete train, which is without the weight of cargo we just

   121 	 * moved back into some (of the) new wagon(s).

   122 	 */

   123 	if (dest->type == VEH_TRAIN) TrainConsistChanged(dest->First(), true);

   124 }

   125 

   126 

   237 /** Replaces a vehicle (used to be called autorenew)

   238  * This function is only called from MaybeReplaceVehicle()

   239  * Must be called with _current_player set to the owner of the vehicle

   240  * @param w Vehicle to replace

   241  * @param flags is the flags to use when calling DoCommand(). Mainly DC_EXEC counts

   242  * @param p The vehicle owner (faster than refinding the pointer)

   243  * @param new_engine_type The EngineID to replace to

   244  * @return value is cost of the replacement or CMD_ERROR

   245  */

   246 static CommandCost ReplaceVehicle(Vehicle **w, uint32 flags, Money total_cost, const Player *p, EngineID new_engine_type)

   247 {

   248 	CommandCost cost;

   249 	CommandCost sell_value;

   250 	Vehicle *old_v = *w;

   251 	const UnitID cached_unitnumber = old_v->unitnumber;

   252 	bool new_front = false;

   253 	Vehicle *new_v = NULL;

   254 	char *vehicle_name = NULL;

   255 	CargoID replacement_cargo_type;

   256 

   257 	replacement_cargo_type = GetNewCargoTypeForReplace(old_v, new_engine_type);

   258 

   259 	/* check if we can't refit to the needed type, so no replace takes place to prevent the vehicle from altering cargo type */

   260 	if (replacement_cargo_type == CT_INVALID) return CommandCost();

   261 

   262 	sell_value = DoCommand(0, old_v->index, 0, DC_QUERY_COST, GetCmdSellVeh(old_v));

   263 

   264 	/* We give the player a loan of the same amount as the sell value.

   265 	 * This is needed in case he needs the income from the sale to build the new vehicle.

   266 	 * We take it back if building fails or when we really sell the old engine */

   267 	SubtractMoneyFromPlayer(sell_value);

   268 

   269 	cost = DoCommand(old_v->tile, new_engine_type, 0, flags | DC_AUTOREPLACE, GetCmdBuildVeh(old_v));

   270 	if (CmdFailed(cost)) {

   271 		/* Take back the money we just gave the player */

   272 		sell_value.MultiplyCost(-1);

   273 		SubtractMoneyFromPlayer(sell_value);

   274 		return cost;

   275 	}

   276 

   277 	if (replacement_cargo_type != CT_NO_REFIT) {

   278 		/* add refit cost */

   279 		CommandCost refit_cost = GetRefitCost(new_engine_type);

   280 		if (old_v->type == VEH_TRAIN && RailVehInfo(new_engine_type)->railveh_type == RAILVEH_MULTIHEAD) {

   281 			/* Since it's a dualheaded engine we have to pay once more because the rear end is being refitted too. */

   282 			refit_cost.AddCost(refit_cost);

   283 		}

   284 		cost.AddCost(refit_cost);

   285 	}

   286 

   287 	if (flags & DC_EXEC) {

   288 		new_v = GetVehicle(_new_vehicle_id);

   289 		*w = new_v; //we changed the vehicle, so MaybeReplaceVehicle needs to work on the new one. Now we tell it what the new one is

   290 

   291 		/* refit if needed */

   292 		if (replacement_cargo_type != CT_NO_REFIT) {

   293 			if (CmdFailed(DoCommand(0, new_v->index, replacement_cargo_type, DC_EXEC, GetCmdRefitVeh(new_v)))) {

   294 				/* Being here shows a failure, which most likely is in GetNewCargoTypeForReplace() or incorrect estimation costs */

   295 				error("Autoreplace failed to refit. Replace engine %d to %d and refit to cargo %d", old_v->engine_type, new_v->engine_type, replacement_cargo_type);

   296 			}

   297 		}

   298 

   299 		if (new_v->type == VEH_TRAIN && HasBit(old_v->u.rail.flags, VRF_REVERSE_DIRECTION) && !IsMultiheaded(new_v) && !(new_v->Next() != NULL && IsArticulatedPart(new_v->Next()))) {

   300 			// we are autorenewing to a single engine, so we will turn it as the old one was turned as well

   301 			SetBit(new_v->u.rail.flags, VRF_REVERSE_DIRECTION);

   302 		}

   303 

   304 		if (old_v->type == VEH_TRAIN && !IsFrontEngine(old_v)) {

   305 			/* this is a railcar. We need to move the car into the train

   306 			 * We add the new engine after the old one instead of replacing it. It will give the same result anyway when we

   307 			 * sell the old engine in a moment

   308 			 */

   309 			/* Get the vehicle in front of the one we move out */

   310 			Vehicle *front = old_v->Previous();

   311 			if (front == NULL) {

   312 				/* It would appear that we have the front wagon of a row of wagons without engines */

   313 				Vehicle *next = old_v->Next();

   314 				if (next != NULL) {

   315 					/* Move the chain to the new front wagon */

   316 					DoCommand(0, (new_v->index << 16) | next->index, 1, DC_EXEC, CMD_MOVE_RAIL_VEHICLE);

   317 				}

   318 			} else {

   319 				/* If the vehicle in front is the rear end of a dualheaded engine, then we need to use the one in front of that one */

   320 				if (IsRearDualheaded(front)) front = front->Previous();

   321 				/* Now we move the old one out of the train */

   322 				DoCommand(0, (INVALID_VEHICLE << 16) | old_v->index, 0, DC_EXEC, CMD_MOVE_RAIL_VEHICLE);

   323 				/* Add the new vehicle */

   324 				CommandCost tmp_move = DoCommand(0, (front->index << 16) | new_v->index, 1, DC_EXEC, CMD_MOVE_RAIL_VEHICLE);

   325 				if (CmdFailed(tmp_move)) {

   326 					cost.AddCost(tmp_move);

   327 					DoCommand(0, new_v->index, 1, DC_EXEC, GetCmdSellVeh(VEH_TRAIN));

   328 				}

   329 			}

   330 		} else {

   331 			// copy/clone the orders

   332 			DoCommand(0, (old_v->index << 16) | new_v->index, old_v->IsOrderListShared() ? CO_SHARE : CO_COPY, DC_EXEC, CMD_CLONE_ORDER);

   333 			new_v->cur_order_index = old_v->cur_order_index;

   334 			ChangeVehicleViewWindow(old_v->index, new_v->index);

   335 			new_v->profit_this_year = old_v->profit_this_year;

   336 			new_v->profit_last_year = old_v->profit_last_year;

   337 			new_v->service_interval = old_v->service_interval;

   338 			DoCommand(0, old_v->group_id, new_v->index, flags, CMD_ADD_VEHICLE_GROUP);

   339 			new_front = true;

   340 			new_v->unitnumber = old_v->unitnumber; // use the same unit number

   341 			new_v->dest_tile  = old_v->dest_tile;

   342 

   343 			new_v->current_order = old_v->current_order;

   344 			if (old_v->type == VEH_TRAIN && GetNextVehicle(old_v) != NULL){

   345 				Vehicle *temp_v = GetNextVehicle(old_v);

   346 

   347 				// move the entire train to the new engine, excluding the old engine

   348 				if (IsMultiheaded(old_v) && temp_v == old_v->u.rail.other_multiheaded_part) {

   349 					// we got front and rear of a multiheaded engine right after each other. We should work with the next in line instead

   350 					temp_v = GetNextVehicle(temp_v);

   351 				}

   352 

   353 				if (temp_v != NULL) {

   354 					CommandCost tmp_move = DoCommand(0, (new_v->index << 16) | temp_v->index, 1, DC_EXEC, CMD_MOVE_RAIL_VEHICLE);

   355 					if (CmdFailed(tmp_move)) {

   356 						cost.AddCost(tmp_move);

   357 						DoCommand(0, temp_v->index, 1, DC_EXEC, GetCmdSellVeh(VEH_TRAIN));

   358 					}

   359 				}

   360 			}

   361 		}

   362 		if (CmdSucceeded(cost)) {

   363 			/* We are done setting up the new vehicle. Now we move the cargo from the old one to the new one */

   364 			MoveVehicleCargo(new_v->type == VEH_TRAIN ? new_v->First() : new_v, old_v);

   365 

   366 			/* Get the name of the old vehicle if it has a custom name. */

   367 			if (old_v->name != NULL) vehicle_name = strdup(old_v->name);

   368 		}

   369 	} else { // flags & DC_EXEC not set

   370 		CommandCost tmp_move;

   371 

   372 		if (old_v->type == VEH_TRAIN && IsFrontEngine(old_v)) {

   373 			Vehicle *next_veh = GetNextUnit(old_v); // don't try to move the rear multiheaded engine or articulated parts

   374 			if (next_veh != NULL) {

   375 				/* Verify that the wagons can be placed on the engine in question.

   376 				 * This is done by building an engine, test if the wagons can be added and then sell the test engine. */

   377 				DoCommand(old_v->tile, new_engine_type, 0, DC_EXEC | DC_AUTOREPLACE, GetCmdBuildVeh(old_v));

   378 				Vehicle *temp = GetVehicle(_new_vehicle_id);

   379 				tmp_move = DoCommand(0, (temp->index << 16) | next_veh->index, 1, 0, CMD_MOVE_RAIL_VEHICLE);

   380 				DoCommand(0, temp->index, 0, DC_EXEC, GetCmdSellVeh(old_v));

   381 			}

   382 		}

   383 

   384 		/* Ensure that the player will not end up having negative money while autoreplacing

   385 		 * This is needed because the only other check is done after the income from selling the old vehicle is substracted from the cost */

   386 		if (CmdFailed(tmp_move) || p->player_money < (cost.GetCost() + total_cost)) {

   387 			/* Pay back the loan */

   388 			sell_value.MultiplyCost(-1);

   389 			SubtractMoneyFromPlayer(sell_value);

   390 			return CMD_ERROR;

   391 		}

   392 	}

   393 

   394 	/* Take back the money we just gave the player just before building the vehicle

   395 	 * The player will get the same amount now that the sale actually takes place */

   396 	sell_value.MultiplyCost(-1);

   397 	SubtractMoneyFromPlayer(sell_value);

   398 

   399 	/* sell the engine/ find out how much you get for the old engine (income is returned as negative cost) */

   400 	cost.AddCost(DoCommand(0, old_v->index, 0, flags, GetCmdSellVeh(old_v)));

   401 

   402 	if (CmdFailed(cost)) return cost;

   403 

   404 	if (new_front) {

   405 		/* now we assign the old unitnumber to the new vehicle */

   406 		new_v->unitnumber = cached_unitnumber;

   407 	}

   408 

   409 	/* Transfer the name of the old vehicle */

   410 	if ((flags & DC_EXEC) && vehicle_name != NULL) {

   411 		_cmd_text = vehicle_name;

   412 		DoCommand(0, new_v->index, 0, DC_EXEC, CMD_NAME_VEHICLE);

   413 		free(vehicle_name);

   414 	}

   415 

   416 	return cost;

   417 }

   418 

   419 /** Removes wagons from a train until it get a certain length

   420  * @param v The vehicle

   421  * @param old_total_length The wanted max length

   422  * @return The profit from selling the wagons

   423  */

   424 static CommandCost WagonRemoval(Vehicle *v, uint16 old_total_length)

   425 {

   426 	if (v->type != VEH_TRAIN) return CommandCost();

   427 	Vehicle *front = v;

   428 

   429 	CommandCost cost = CommandCost();

   430 

   431 	while (front->u.rail.cached_total_length > old_total_length) {

   432 		/* the train is too long. We will remove cars one by one from the start of the train until it's short enough */

   433 		while (v != NULL && RailVehInfo(v->engine_type)->railveh_type != RAILVEH_WAGON) {

   434 			/* We move backwards in the train until we find a wagon */

   435 			v = GetNextVehicle(v);

   436 		}

   437 

   438 		if (v == NULL) {

   439 			/* We sold all the wagons and the train is still not short enough */

   440 			SetDParam(0, front->unitnumber);

   441 			AddNewsItem(STR_TRAIN_TOO_LONG_AFTER_REPLACEMENT, NS_ADVICE, front->index, 0);

   442 			return cost;

   443 		}

   444 

   445 		/* We found a wagon we can sell */

   446 		Vehicle *temp = v;

   447 		v = GetNextVehicle(v);

   448 		DoCommand(0, (INVALID_VEHICLE << 16) | temp->index, 0, DC_EXEC, CMD_MOVE_RAIL_VEHICLE); // remove the wagon from the train

   449 		MoveVehicleCargo(front, temp); // move the cargo back on the train

   450 		cost.AddCost(DoCommand(0, temp->index, 0, DC_EXEC, CMD_SELL_RAIL_WAGON)); // sell the wagon

   451 	}

   452 	return cost;

   453 }

   454 

   481 }

   482 

   483 /** replaces a vehicle if it's set for autoreplace or is too old

   484  * (used to be called autorenew)

   485  * @param v The vehicle to replace

   486  * if the vehicle is a train, v needs to be the front engine

   487  * @param flags

   488  * @param display_costs If set, a cost animation is shown (only if DC_EXEC is set)

   489  *        This bool also takes autorenew money into consideration

   490  * @return the costs, the success bool and sometimes an error message

   491  */

   492 CommandCost MaybeReplaceVehicle(Vehicle *v, uint32 flags, bool display_costs)

   493 {

   494 	Vehicle *w;

   495 	Player *p = GetPlayer(v->owner);

   496 	CommandCost cost;

   497 	bool stopped = false;

   498 	BackuppedVehicle backup(true);

   499 

   500 	/* We only want "real" vehicle types. */

   501 	assert(IsPlayerBuildableVehicleType(v));

   502 

   503 	/* Ensure that this bool is cleared. */

   504 	assert(!v->leave_depot_instantly);

   505 

   506 	/* We can't sell if the current player don't own the vehicle. */

   507 	assert(v->owner == _current_player);

   508 

   509 	if (!v->IsInDepot()) {

   510 		/* The vehicle should be inside the depot */

   511 		switch (v->type) {

   512 			default: NOT_REACHED();

   513 			case VEH_TRAIN:    return_cmd_error(STR_881A_TRAINS_CAN_ONLY_BE_ALTERED); break;

   514 			case VEH_ROAD:     return_cmd_error(STR_9013_MUST_BE_STOPPED_INSIDE);     break;

   515 			case VEH_SHIP:     return_cmd_error(STR_980B_SHIP_MUST_BE_STOPPED_IN);    break;

   516 			case VEH_AIRCRAFT: return_cmd_error(STR_A01B_AIRCRAFT_MUST_BE_STOPPED);   break;

   517 		}

   518 	}

   519 

   520 	/* Remember the length in case we need to trim train later on

   521 	 * If it's not a train, the value is unused

   522 	 * round up to the length of the tiles used for the train instead of the train length instead

   523 	 * Useful when newGRF uses custom length */

   524 	uint16 old_total_length = (v->type == VEH_TRAIN ?

   525 		(v->u.rail.cached_total_length + TILE_SIZE - 1) / TILE_SIZE * TILE_SIZE :

   526 		-1

   527 	);

   528 

   529 	if (!(v->vehstatus & VS_STOPPED)) {

   530 		/* The vehicle is moving so we better stop it before we might alter consist or sell it */

   531 		v->vehstatus |= VS_STOPPED;

   532 		/* Remember that we stopped the vehicle */

   533 		stopped = true;

   534 	}

   535 

   536 	{

   537 		cost = CommandCost(EXPENSES_NEW_VEHICLES);

   538 		w = v;

   539 		do {

   540 			EngineID new_engine = GetNewEngineType(w, p);

   541 			if (new_engine == INVALID_ENGINE) continue;

   542 

   543 			if (!backup.ContainsBackup()) {

   544 				/* We are going to try to replace a vehicle but we don't have any backup so we will make one. */

   545 				backup.Backup(v, p);

   546 			}

   547 			/* Now replace the vehicle.

   548 			 * First we need to cache if it's the front vehicle as we need to update the v pointer if it is.

   549 			 * If the replacement fails then we can't trust the data in the vehicle hence the reason to cache the result. */

   550 			bool IsFront = w->type != VEH_TRAIN || w->u.rail.first_engine == INVALID_ENGINE;

   551 

   552 			cost.AddCost(ReplaceVehicle(&w, DC_EXEC, cost.GetCost(), p, new_engine));

   553 

   554 			if (IsFront) {

   555 				/* now we bought a new engine and sold the old one. We need to fix the

   556 				 * pointers in order to avoid pointing to the old one for trains: these

   557 				 * pointers should point to the front engine and not the cars

   558 				 */

   559 				v = w;

   560 			}

   561 		} while (CmdSucceeded(cost) && w->type == VEH_TRAIN && (w = GetNextVehicle(w)) != NULL);

   562 

   563 		if (CmdSucceeded(cost) && v->type == VEH_TRAIN && p->renew_keep_length) {

   564 			/* Remove wagons until the wanted length is reached */

   565 			cost.AddCost(WagonRemoval(v, old_total_length));

   566 		}

   567 

   568 		if (flags & DC_QUERY_COST || cost.GetCost() == 0) {

   569 			/* We didn't do anything during the replace so we will just exit here */

   570 			v = backup.Restore(v, p);

   571 			if (stopped) v->vehstatus &= ~VS_STOPPED;

   572 			return cost;

   573 		}

   574 

   575 		if (display_costs) {

   576 			/* We want to ensure that we will not get below p->engine_renew_money.

   577 			 * We will not actually pay this amount. It's for display and checks only. */

   578 			CommandCost tmp = cost;

   579 			tmp.AddCost((Money)p->engine_renew_money);

   580 			if (CmdSucceeded(tmp) && GetAvailableMoneyForCommand() < tmp.GetCost()) {

   581 				/* We don't have enough money so we will set cost to failed */

   582 				cost.AddCost((Money)p->engine_renew_money);

   583 				cost.AddCost(CMD_ERROR);

   584 			}

   585 		}

   586 

   587 		if (display_costs && CmdFailed(cost)) {

   588 			if (GetAvailableMoneyForCommand() < cost.GetCost() && IsLocalPlayer()) {

   589 				StringID message;

   590 				SetDParam(0, v->unitnumber);

   591 				switch (v->type) {

   592 					case VEH_TRAIN:    message = STR_TRAIN_AUTORENEW_FAILED;       break;

   593 					case VEH_ROAD:     message = STR_ROADVEHICLE_AUTORENEW_FAILED; break;

   594 					case VEH_SHIP:     message = STR_SHIP_AUTORENEW_FAILED;        break;

   595 					case VEH_AIRCRAFT: message = STR_AIRCRAFT_AUTORENEW_FAILED;    break;

   596 						// This should never happen

   597 					default: NOT_REACHED(); message = 0; break;

   598 				}

   599 

   600 				AddNewsItem(message, NS_ADVICE, v->index, 0);

   601 			}

   602 		}

   603 	}

   604 

   605 	if (display_costs && IsLocalPlayer() && (flags & DC_EXEC) && CmdSucceeded(cost)) {

   606 		ShowCostOrIncomeAnimation(v->x_pos, v->y_pos, v->z_pos, cost.GetCost());

   607 	}

   608 

   609 	if (!(flags & DC_EXEC) || CmdFailed(cost)) {

   610 		v = backup.Restore(v, p);

   611 	}

   612 

   613 	/* Start the vehicle if we stopped it earlier */

   614 	if (stopped) v->vehstatus &= ~VS_STOPPED;

   615 

   616 	return cost;