OpenTTD-patches/src/autoreplace.cpp
2023-02-26 21:29:25 +01:00

157 lines
5.0 KiB
C++

/*
* 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 autoreplace.cpp Management of replacement lists. */
#include "stdafx.h"
#include "command_func.h"
#include "group.h"
#include "autoreplace_base.h"
#include "core/bitmath_func.hpp"
#include "core/pool_func.hpp"
#include "safeguards.h"
/** The pool of autoreplace "orders". */
EngineRenewPool _enginerenew_pool("EngineRenew");
INSTANTIATE_POOL_METHODS(EngineRenew)
/**
* Retrieves the EngineRenew that specifies the replacement of the given
* engine type from the given renewlist
*/
static EngineRenew *GetEngineReplacement(EngineRenewList erl, EngineID engine, GroupID group)
{
EngineRenew *er = (EngineRenew *)erl;
while (er != nullptr) {
if (er->from == engine && GroupIsInGroup(group, er->group_id)) return er;
er = er->next;
}
return nullptr;
}
/**
* Remove all engine replacement settings for the company.
* @param erl The renewlist for a given company.
* @return The new renewlist for the company.
*/
void RemoveAllEngineReplacement(EngineRenewList *erl)
{
EngineRenew *er = (EngineRenew *)(*erl);
EngineRenew *next;
while (er != nullptr) {
next = er->next;
delete er;
er = next;
}
*erl = nullptr; // Empty list
}
/**
* Retrieve the engine replacement in a given renewlist for an original engine type.
* @param erl The renewlist to search in.
* @param engine Engine type to be replaced.
* @param group The group related to this replacement.
* @param[out] replace_when_old Set to true if the replacement should be done when old.
* @return The engine type to replace with, or INVALID_ENGINE if no
* replacement is in the list.
*/
EngineID EngineReplacement(EngineRenewList erl, EngineID engine, GroupID group, bool *replace_when_old)
{
const EngineRenew *er = GetEngineReplacement(erl, engine, group);
if (er == nullptr && (group == DEFAULT_GROUP || (Group::IsValidID(group) && !HasBit(Group::Get(group)->flags, GroupFlags::GF_REPLACE_PROTECTION)))) {
/* We didn't find anything useful in the vehicle's own group so we will try ALL_GROUP */
er = GetEngineReplacement(erl, engine, ALL_GROUP);
}
if (replace_when_old != nullptr) {
if (er == nullptr) {
/* Not replacing */
*replace_when_old = false;
} else if (er->to == engine) {
/* When replacing with same model, only ever do it when old */
*replace_when_old = true;
} else {
/* Use player setting */
*replace_when_old = er->replace_when_old;
}
}
return er == nullptr ? INVALID_ENGINE : er->to;
}
/**
* Add an engine replacement to the given renewlist.
* @param erl The renewlist to add to.
* @param old_engine The original engine type.
* @param new_engine The replacement engine type.
* @param group The group related to this replacement.
* @param replace_when_old Replace when old or always?
* @param flags The calling command flags.
* @return 0 on success, CMD_ERROR on failure.
*/
CommandCost AddEngineReplacement(EngineRenewList *erl, EngineID old_engine, EngineID new_engine, GroupID group, bool replace_when_old, DoCommandFlag flags)
{
/* Check if the old vehicle is already in the list */
EngineRenew *er = GetEngineReplacement(*erl, old_engine, group);
if (er != nullptr) {
if (flags & DC_EXEC) {
er->to = new_engine;
er->replace_when_old = replace_when_old;
}
return CommandCost();
}
if (!EngineRenew::CanAllocateItem()) return CMD_ERROR;
if (flags & DC_EXEC) {
er = new EngineRenew(old_engine, new_engine);
er->group_id = group;
er->replace_when_old = replace_when_old;
/* Insert before the first element */
er->next = (EngineRenew *)(*erl);
*erl = (EngineRenewList)er;
}
return CommandCost();
}
/**
* Remove an engine replacement from a given renewlist.
* @param erl The renewlist from which to remove the replacement
* @param engine The original engine type.
* @param group The group related to this replacement.
* @param flags The calling command flags.
* @return 0 on success, CMD_ERROR on failure.
*/
CommandCost RemoveEngineReplacement(EngineRenewList *erl, EngineID engine, GroupID group, DoCommandFlag flags)
{
EngineRenew *er = (EngineRenew *)(*erl);
EngineRenew *prev = nullptr;
while (er != nullptr) {
if (er->from == engine && er->group_id == group) {
if (flags & DC_EXEC) {
if (prev == nullptr) { // First element
/* The second becomes the new first element */
*erl = (EngineRenewList)er->next;
} else {
/* Cut this element out */
prev->next = er->next;
}
delete er;
}
return CommandCost();
}
prev = er;
er = er->next;
}
return CMD_ERROR;
}