autoreplace.cpp

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/* $Id: autoreplace.cpp 14828 2009-01-04 15:32:25Z smatz $ */

#include "stdafx.h"
#include "openttd.h"
#include "debug.h"
#include "command_func.h"
#include "group.h"
#include "autoreplace_base.h"
#include "oldpool_func.h"

DEFINE_OLD_POOL_GENERIC(EngineRenew, EngineRenew)


static EngineRenew *GetEngineReplacement(EngineRenewList erl, EngineID engine, GroupID group)
{
  EngineRenew *er = (EngineRenew *)erl;

  while (er) {
    if (er->from == engine && er->group_id == group) return er;
    er = er->next;
  }
  return NULL;
}

void RemoveAllEngineReplacement(EngineRenewList *erl)
{
  EngineRenew *er = (EngineRenew *)(*erl);
  EngineRenew *next;

  while (er != NULL) {
    next = er->next;
    delete er;
    er = next;
  }
  *erl = NULL; // Empty list
}

EngineID EngineReplacement(EngineRenewList erl, EngineID engine, GroupID group)
{
  const EngineRenew *er = GetEngineReplacement(erl, engine, group);
  if (er == NULL && (group == DEFAULT_GROUP || (IsValidGroupID(group) && !GetGroup(group)->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);
  }
  return er == NULL ? INVALID_ENGINE : er->to;
}

CommandCost AddEngineReplacement(EngineRenewList *erl, EngineID old_engine, EngineID new_engine, GroupID group, uint32 flags)
{
  EngineRenew *er;

  /* Check if the old vehicle is already in the list */
  er = GetEngineReplacement(*erl, old_engine, group);
  if (er != NULL) {
    if (flags & DC_EXEC) er->to = new_engine;
    return CommandCost();
  }

  if (!EngineRenew::CanAllocateItem()) return CMD_ERROR;

  if (flags & DC_EXEC) {
    er = new EngineRenew(old_engine, new_engine);
    er->group_id = group;

    /* Insert before the first element */
    er->next = (EngineRenew *)(*erl);
    *erl = (EngineRenewList)er;
  }

  return CommandCost();
}

CommandCost RemoveEngineReplacement(EngineRenewList *erl, EngineID engine, GroupID group, uint32 flags)
{
  EngineRenew *er = (EngineRenew *)(*erl);
  EngineRenew *prev = NULL;

  while (er)
  {
    if (er->from == engine && er->group_id == group) {
      if (flags & DC_EXEC) {
        if (prev == NULL) { // 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;
}

void InitializeEngineRenews()
{
  /* Clean the engine renew pool and create 1 block in it */
  _EngineRenew_pool.CleanPool();
  _EngineRenew_pool.AddBlockToPool();
}