src/engine.cpp
author truebrain
Thu, 12 Jun 2008 19:47:02 +0000
branchnoai
changeset 10942 cd3f2d07199f
parent 10867 5de2923d6e59
child 10971 aaf89f8c59b9
permissions -rw-r--r--
(svn r13496) [NoAI] -Fix: if a library depends on an other library, the import became globally known, which defeats the idea of imports. They are now restricted to their scope, and 'import' returns the class of import (if any)
/* $Id$ */

/** @file engine.cpp Base for all engine handling. */

#include "stdafx.h"
#include "openttd.h"
#include "debug.h"
#include "player_base.h"
#include "player_func.h"
#include "command_func.h"
#include "news_func.h"
#include "saveload.h"
#include "variables.h"
#include "train.h"
#include "aircraft.h"
#include "newgrf_cargo.h"
#include "newgrf_engine.h"
#include "group.h"
#include "strings_func.h"
#include "gfx_func.h"
#include "functions.h"
#include "window_func.h"
#include "date_func.h"
#include "autoreplace_base.h"
#include "autoreplace_gui.h"
#include "string_func.h"
#include "settings_type.h"
#include "oldpool_func.h"
#include "ai/ai.h"
#include "core/alloc_func.hpp"
#include "vehicle_func.h"
#include <map>

#include "table/strings.h"
#include "table/engines.h"

DEFINE_OLD_POOL_GENERIC(Engine, Engine)

enum {
	YEAR_ENGINE_AGING_STOPS = 2050,
};


/** Number of engines of each vehicle type in original engine data */
const uint8 _engine_counts[4] = {
	lengthof(_orig_rail_vehicle_info),
	lengthof(_orig_road_vehicle_info),
	lengthof(_orig_ship_vehicle_info),
	lengthof(_orig_aircraft_vehicle_info),
};

/** Offset of the first engine of each vehicle type in original engine data */
const uint8 _engine_offsets[4] = {
	0,
	lengthof(_orig_rail_vehicle_info),
	lengthof(_orig_rail_vehicle_info) + lengthof(_orig_road_vehicle_info),
	lengthof(_orig_rail_vehicle_info) + lengthof(_orig_road_vehicle_info) + lengthof(_orig_ship_vehicle_info),
};

Engine::Engine() :
	name(NULL),
	overrides_count(0),
	overrides(NULL)
{
}

Engine::Engine(VehicleType type, EngineID base)
{
	this->type = type;
	this->internal_id = base;
	this->list_position = base;

	/* Check if this base engine is within the original engine data range */
	if (base >= _engine_counts[type]) {
		/* Mark engine as valid anyway */
		this->info.climates = 0x80;
		return;
	}

	/* Copy the original engine info for this slot */
	this->info = _orig_engine_info[_engine_offsets[type] + base];

	/* Copy the original engine data for this slot */
	switch (type) {
		default: NOT_REACHED();

		case VEH_TRAIN:
			this->u.rail = _orig_rail_vehicle_info[base];
			this->image_index = this->u.rail.image_index;
			this->info.string_id = STR_8000_KIRBY_PAUL_TANK_STEAM + base;
			break;

		case VEH_ROAD:
			this->u.road = _orig_road_vehicle_info[base];
			this->image_index = this->u.road.image_index;
			this->info.string_id = STR_8074_MPS_REGAL_BUS + base;
			break;

		case VEH_SHIP:
			this->u.ship = _orig_ship_vehicle_info[base];
			this->image_index = this->u.ship.image_index;
			this->info.string_id = STR_80CC_MPS_OIL_TANKER + base;
			break;

		case VEH_AIRCRAFT:
			this->u.air = _orig_aircraft_vehicle_info[base];
			this->image_index = this->u.air.image_index;
			this->info.string_id = STR_80D7_SAMPSON_U52 + base;
			break;
	}
}

Engine::~Engine()
{
	UnloadWagonOverrides(this);
	free(this->name);
}

/** Sets cached values in Player::num_vehicles and Group::num_vehicles
 */
void SetCachedEngineCounts()
{
	uint engines = GetEnginePoolSize();

	/* Set up the engine count for all players */
	Player *p;
	FOR_ALL_PLAYERS(p) {
		free(p->num_engines);
		p->num_engines = CallocT<EngineID>(engines);
	}

	/* Recalculate */
	Group *g;
	FOR_ALL_GROUPS(g) {
		free(g->num_engines);
		g->num_engines = CallocT<EngineID>(engines);
	}

	const Vehicle *v;
	FOR_ALL_VEHICLES(v) {
		if (!IsEngineCountable(v)) continue;

		assert(v->engine_type < engines);

		GetPlayer(v->owner)->num_engines[v->engine_type]++;

		if (v->group_id == DEFAULT_GROUP) continue;

		g = GetGroup(v->group_id);
		assert(v->type == g->vehicle_type);
		assert(v->owner == g->owner);

		g->num_engines[v->engine_type]++;
	}
}

void SetupEngines()
{
	_Engine_pool.CleanPool();
	_Engine_pool.AddBlockToPool();

	for (uint i = 0; i < lengthof(_orig_rail_vehicle_info); i++) new Engine(VEH_TRAIN, i);
	for (uint i = 0; i < lengthof(_orig_road_vehicle_info); i++) new Engine(VEH_ROAD, i);
	for (uint i = 0; i < lengthof(_orig_ship_vehicle_info); i++) new Engine(VEH_SHIP, i);
	for (uint i = 0; i < lengthof(_orig_aircraft_vehicle_info); i++) new Engine(VEH_AIRCRAFT, i);
}


void ShowEnginePreviewWindow(EngineID engine);

void DeleteCustomEngineNames()
{
	Engine *e;
	FOR_ALL_ENGINES(e) {
		free(e->name);
		e->name = NULL;
	}

	_vehicle_design_names &= ~1;
}

void LoadCustomEngineNames()
{
	/* XXX: not done */
	DEBUG(misc, 1, "LoadCustomEngineNames: not done");
}

/* Determine if an engine type is a wagon (and not a loco) */
static bool IsWagon(EngineID index)
{
	const Engine *e = GetEngine(index);
	return e->type == VEH_TRAIN && e->u.rail.railveh_type == RAILVEH_WAGON;
}

static void CalcEngineReliability(Engine *e)
{
	uint age = e->age;

	/* Check for early retirement */
	if (e->player_avail != 0 && !_settings_game.vehicle.never_expire_vehicles) {
		int retire_early = e->info.retire_early;
		uint retire_early_max_age = max(0, e->duration_phase_1 + e->duration_phase_2 - retire_early * 12);
		if (retire_early != 0 && age >= retire_early_max_age) {
			/* Early retirement is enabled and we're past the date... */
			e->player_avail = 0;
			AddRemoveEngineFromAutoreplaceAndBuildWindows(e->type);
		}
	}

	if (age < e->duration_phase_1) {
		uint start = e->reliability_start;
		e->reliability = age * (e->reliability_max - start) / e->duration_phase_1 + start;
	} else if ((age -= e->duration_phase_1) < e->duration_phase_2 || _settings_game.vehicle.never_expire_vehicles) {
		/* We are at the peak of this engines life. It will have max reliability.
		 * This is also true if the engines never expire. They will not go bad over time */
		e->reliability = e->reliability_max;
	} else if ((age -= e->duration_phase_2) < e->duration_phase_3) {
		uint max = e->reliability_max;
		e->reliability = (int)age * (int)(e->reliability_final - max) / e->duration_phase_3 + max;
	} else {
		/* time's up for this engine.
		 * We will now completely retire this design */
		e->player_avail = 0;
		e->reliability = e->reliability_final;
		/* Kick this engine out of the lists */
		AddRemoveEngineFromAutoreplaceAndBuildWindows(e->type);
	}
	InvalidateWindowClasses(WC_BUILD_VEHICLE); // Update to show the new reliability
	InvalidateWindowClasses(WC_REPLACE_VEHICLE);
}

void StartupEngines()
{
	Engine *e;
	/* Aging of vehicles stops, so account for that when starting late */
	const Date aging_date = min(_date, ConvertYMDToDate(YEAR_ENGINE_AGING_STOPS, 0, 1));

	FOR_ALL_ENGINES(e) {
		const EngineInfo *ei = &e->info;
		uint32 r;

		e->age = 0;
		e->flags = 0;
		e->player_avail = 0;

		/* The magic value of 729 days below comes from the NewGRF spec. If the
		 * base intro date is before 1922 then the random number of days is not
		 * added. */
		r = Random();
		e->intro_date = ei->base_intro <= ConvertYMDToDate(1922, 0, 1) ? ei->base_intro : (Date)GB(r, 0, 9) + ei->base_intro;
		if (e->intro_date <= _date) {
			e->age = (aging_date - e->intro_date) >> 5;
			e->player_avail = (byte)-1;
			e->flags |= ENGINE_AVAILABLE;
		}

		e->reliability_start = GB(r, 16, 14) + 0x7AE0;
		r = Random();
		e->reliability_max   = GB(r,  0, 14) + 0xBFFF;
		e->reliability_final = GB(r, 16, 14) + 0x3FFF;

		r = Random();
		e->duration_phase_1 = GB(r, 0, 5) + 7;
		e->duration_phase_2 = GB(r, 5, 4) + ei->base_life * 12 - 96;
		e->duration_phase_3 = GB(r, 9, 7) + 120;

		e->reliability_spd_dec = ei->decay_speed << 2;

		if (IsWagon(e->index)) {
			e->age = 0xFFFF;
		} else {
			CalcEngineReliability(e);
		}

		e->lifelength = ei->lifelength + _settings_game.vehicle.extend_vehicle_life;

		/* prevent certain engines from ever appearing. */
		if (!HasBit(ei->climates, _settings_game.game_creation.landscape)) {
			e->flags |= ENGINE_AVAILABLE;
			e->player_avail = 0;
		}
	}
}

static void AcceptEnginePreview(EngineID eid, PlayerID player)
{
	Engine *e = GetEngine(eid);
	Player *p = GetPlayer(player);

	SetBit(e->player_avail, player);
	if (e->type == VEH_TRAIN) {
		const RailVehicleInfo *rvi = RailVehInfo(eid);

		assert(rvi->railtype < RAILTYPE_END);
		SetBit(p->avail_railtypes, rvi->railtype);
	} else if (e->type == VEH_ROAD) {
		SetBit(p->avail_roadtypes, HasBit(EngInfo(eid)->misc_flags, EF_ROAD_TRAM) ? ROADTYPE_TRAM : ROADTYPE_ROAD);
	}

	e->preview_player_rank = 0xFF;
	if (player == _local_player) {
		AddRemoveEngineFromAutoreplaceAndBuildWindows(e->type);
	}
}

static PlayerID GetBestPlayer(uint8 pp)
{
	const Player *p;
	int32 best_hist;
	PlayerID best_player;
	uint mask = 0;

	do {
		best_hist = -1;
		best_player = PLAYER_SPECTATOR;
		FOR_ALL_PLAYERS(p) {
			if (p->is_active && p->block_preview == 0 && !HasBit(mask, p->index) &&
					p->old_economy[0].performance_history > best_hist) {
				best_hist = p->old_economy[0].performance_history;
				best_player = p->index;
			}
		}

		if (best_player == PLAYER_SPECTATOR) return PLAYER_SPECTATOR;

		SetBit(mask, best_player);
	} while (--pp != 0);

	return best_player;
}

void EnginesDailyLoop()
{
	if (_cur_year >= YEAR_ENGINE_AGING_STOPS) return;

	Engine *e;
	FOR_ALL_ENGINES(e) {
		EngineID i = e->index;
		if (e->flags & ENGINE_EXCLUSIVE_PREVIEW) {
			if (e->flags & ENGINE_OFFER_WINDOW_OPEN) {
				if (e->preview_player_rank != 0xFF && !--e->preview_wait) {
					e->flags &= ~ENGINE_OFFER_WINDOW_OPEN;
					DeleteWindowById(WC_ENGINE_PREVIEW, i);
					e->preview_player_rank++;
				}
			} else if (e->preview_player_rank != 0xFF) {
				PlayerID best_player = GetBestPlayer(e->preview_player_rank);

				if (best_player == PLAYER_SPECTATOR) {
					e->preview_player_rank = 0xFF;
					continue;
				}

				e->flags |= ENGINE_OFFER_WINDOW_OPEN;
				e->preview_wait = 20;
				AI_Event(best_player, new AIEventEnginePreview(i));
				if (IsInteractivePlayer(best_player)) ShowEnginePreviewWindow(i);
			}
		}
	}
}

/** Accept an engine prototype. XXX - it is possible that the top-player
 * changes while you are waiting to accept the offer? Then it becomes invalid
 * @param tile unused
 * @param flags operation to perfom
 * @param p1 engine-prototype offered
 * @param p2 unused
 */
CommandCost CmdWantEnginePreview(TileIndex tile, uint32 flags, uint32 p1, uint32 p2)
{
	Engine *e;

	if (!IsEngineIndex(p1)) return CMD_ERROR;
	e = GetEngine(p1);
	if (GetBestPlayer(e->preview_player_rank) != _current_player) return CMD_ERROR;

	if (flags & DC_EXEC) AcceptEnginePreview(p1, _current_player);

	return CommandCost();
}

StringID GetEngineCategoryName(EngineID engine);

static void NewVehicleAvailable(Engine *e)
{
	Vehicle *v;
	Player *p;
	EngineID index = e->index;

	/* In case the player didn't build the vehicle during the intro period,
	 * prevent that player from getting future intro periods for a while. */
	if (e->flags & ENGINE_EXCLUSIVE_PREVIEW) {
		FOR_ALL_PLAYERS(p) {
			uint block_preview = p->block_preview;

			if (!HasBit(e->player_avail, p->index)) continue;

			/* We assume the user did NOT build it.. prove me wrong ;) */
			p->block_preview = 20;

			FOR_ALL_VEHICLES(v) {
				if (v->type == VEH_TRAIN || v->type == VEH_ROAD || v->type == VEH_SHIP ||
						(v->type == VEH_AIRCRAFT && IsNormalAircraft(v))) {
					if (v->owner == p->index && v->engine_type == index) {
						/* The user did prove me wrong, so restore old value */
						p->block_preview = block_preview;
						break;
					}
				}
			}
		}
	}

	e->flags = (e->flags & ~ENGINE_EXCLUSIVE_PREVIEW) | ENGINE_AVAILABLE;
	AddRemoveEngineFromAutoreplaceAndBuildWindows(e->type);

	/* Now available for all players */
	e->player_avail = (byte)-1;

	/* Do not introduce new rail wagons */
	if (IsWagon(index)) return;

	if (e->type == VEH_TRAIN) {
		/* maybe make another rail type available */
		RailType railtype = e->u.rail.railtype;
		assert(railtype < RAILTYPE_END);
		FOR_ALL_PLAYERS(p) {
			if (p->is_active) SetBit(p->avail_railtypes, railtype);
		}
	} else if (e->type == VEH_ROAD) {
		/* maybe make another road type available */
		FOR_ALL_PLAYERS(p) {
			if (p->is_active) SetBit(p->avail_roadtypes, HasBit(e->info.misc_flags, EF_ROAD_TRAM) ? ROADTYPE_TRAM : ROADTYPE_ROAD);
		}
	}

	SetDParam(0, GetEngineCategoryName(index));
	SetDParam(1, index);
	AddNewsItem(STR_NEW_VEHICLE_NOW_AVAILABLE_WITH_TYPE, NS_NEW_VEHICLES, index, 0);
}

void EnginesMonthlyLoop()
{
	if (_cur_year < YEAR_ENGINE_AGING_STOPS) {
		Engine *e;
		FOR_ALL_ENGINES(e) {
			/* Age the vehicle */
			if (e->flags & ENGINE_AVAILABLE && e->age != 0xFFFF) {
				e->age++;
				CalcEngineReliability(e);
			}

			if (!(e->flags & ENGINE_AVAILABLE) && _date >= (e->intro_date + 365)) {
				/* Introduce it to all players */
				NewVehicleAvailable(e);
			} else if (!(e->flags & (ENGINE_AVAILABLE|ENGINE_EXCLUSIVE_PREVIEW)) && _date >= e->intro_date) {
				/* Introduction date has passed.. show introducing dialog to one player. */
				e->flags |= ENGINE_EXCLUSIVE_PREVIEW;

				/* Do not introduce new rail wagons */
				if (!IsWagon(e->index))
					e->preview_player_rank = 1; // Give to the player with the highest rating.
			}
		}
	}
}

static bool IsUniqueEngineName(const char *name)
{
	char buf[512];

	const Engine *e;
	FOR_ALL_ENGINES(e) {
		SetDParam(0, e->index);
		GetString(buf, STR_ENGINE_NAME, lastof(buf));
		if (strcmp(buf, name) == 0) return false;
	}

	return true;
}

/** Rename an engine.
 * @param tile unused
 * @param flags operation to perfom
 * @param p1 engine ID to rename
 * @param p2 unused
 */
CommandCost CmdRenameEngine(TileIndex tile, uint32 flags, uint32 p1, uint32 p2)
{
	if (!IsEngineIndex(p1) || StrEmpty(_cmd_text)) return CMD_ERROR;

	if (!IsUniqueEngineName(_cmd_text)) return_cmd_error(STR_NAME_MUST_BE_UNIQUE);

	if (flags & DC_EXEC) {
		Engine *e = GetEngine(p1);
		free(e->name);
		e->name = strdup(_cmd_text);
		_vehicle_design_names |= 3;
		MarkWholeScreenDirty();
	}

	return CommandCost();
}


/** Check if an engine is buildable.
 * @param engine index of the engine to check.
 * @param type   the type the engine should be.
 * @param player index of the player.
 * @return True if an engine is valid, of the specified type, and buildable by
 *              the given player.
 */
bool IsEngineBuildable(EngineID engine, VehicleType type, PlayerID player)
{
	/* check if it's an engine that is in the engine array */
	if (!IsEngineIndex(engine)) return false;

	const Engine *e = GetEngine(engine);

	/* check if it's an engine of specified type */
	if (e->type != type) return false;

	/* check if it's available */
	if (!HasBit(e->player_avail, player)) return false;

	if (type == VEH_TRAIN) {
		/* Check if the rail type is available to this player */
		const Player *p = GetPlayer(player);
		if (!HasBit(p->avail_railtypes, RailVehInfo(engine)->railtype)) return false;
	}

	return true;
}

/** Get the default cargo type for a certain engine type
 * @param engine The ID to get the cargo for
 * @return The cargo type. CT_INVALID means no cargo capacity
 */
CargoID GetEngineCargoType(EngineID engine)
{
	assert(IsEngineIndex(engine));

	switch (GetEngine(engine)->type) {
		case VEH_TRAIN:
			if (RailVehInfo(engine)->capacity == 0) return CT_INVALID;
			return RailVehInfo(engine)->cargo_type;

		case VEH_ROAD:
			if (RoadVehInfo(engine)->capacity == 0) return CT_INVALID;
			return RoadVehInfo(engine)->cargo_type;

		case VEH_SHIP:
			if (ShipVehInfo(engine)->capacity == 0) return CT_INVALID;
			return ShipVehInfo(engine)->cargo_type;

		case VEH_AIRCRAFT:
			/* all aircraft starts as passenger planes with cargo capacity */
			return CT_PASSENGERS;

		default: NOT_REACHED(); return CT_INVALID;
	}
}

/************************************************************************
 * Engine Replacement stuff
 ************************************************************************/

DEFINE_OLD_POOL_GENERIC(EngineRenew, 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) {
		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;
}

static const SaveLoad _engine_renew_desc[] = {
	    SLE_VAR(EngineRenew, from,     SLE_UINT16),
	    SLE_VAR(EngineRenew, to,       SLE_UINT16),

	    SLE_REF(EngineRenew, next,     REF_ENGINE_RENEWS),
	SLE_CONDVAR(EngineRenew, group_id, SLE_UINT16, 60, SL_MAX_VERSION),
	SLE_END()
};

static void Save_ERNW()
{
	EngineRenew *er;

	FOR_ALL_ENGINE_RENEWS(er) {
		SlSetArrayIndex(er->index);
		SlObject(er, _engine_renew_desc);
	}
}

static void Load_ERNW()
{
	int index;

	while ((index = SlIterateArray()) != -1) {
		EngineRenew *er = new (index) EngineRenew();
		SlObject(er, _engine_renew_desc);

		/* Advanced vehicle lists, ungrouped vehicles got added */
		if (CheckSavegameVersion(60)) {
			er->group_id = ALL_GROUP;
		} else if (CheckSavegameVersion(71)) {
			if (er->group_id == DEFAULT_GROUP) er->group_id = ALL_GROUP;
		}
	}
}

static const SaveLoad _engine_desc[] = {
	SLE_CONDVAR(Engine, intro_date,          SLE_FILE_U16 | SLE_VAR_I32,  0,  30),
	SLE_CONDVAR(Engine, intro_date,          SLE_INT32,                  31, SL_MAX_VERSION),
	SLE_CONDVAR(Engine, age,                 SLE_FILE_U16 | SLE_VAR_I32,  0,  30),
	SLE_CONDVAR(Engine, age,                 SLE_INT32,                  31, SL_MAX_VERSION),
	    SLE_VAR(Engine, reliability,         SLE_UINT16),
	    SLE_VAR(Engine, reliability_spd_dec, SLE_UINT16),
	    SLE_VAR(Engine, reliability_start,   SLE_UINT16),
	    SLE_VAR(Engine, reliability_max,     SLE_UINT16),
	    SLE_VAR(Engine, reliability_final,   SLE_UINT16),
	    SLE_VAR(Engine, duration_phase_1,    SLE_UINT16),
	    SLE_VAR(Engine, duration_phase_2,    SLE_UINT16),
	    SLE_VAR(Engine, duration_phase_3,    SLE_UINT16),

	    SLE_VAR(Engine, lifelength,          SLE_UINT8),
	    SLE_VAR(Engine, flags,               SLE_UINT8),
	    SLE_VAR(Engine, preview_player_rank, SLE_UINT8),
	    SLE_VAR(Engine, preview_wait,        SLE_UINT8),
	SLE_CONDNULL(1, 0, 44),
	    SLE_VAR(Engine, player_avail,        SLE_UINT8),
	SLE_CONDSTR(Engine, name,                SLE_STR, 0,                 84, SL_MAX_VERSION),

	/* reserve extra space in savegame here. (currently 16 bytes) */
	SLE_CONDNULL(16, 2, SL_MAX_VERSION),

	SLE_END()
};

static std::map<EngineID, Engine> _temp_engine;

Engine *GetTempDataEngine(EngineID index)
{
	return &_temp_engine[index];
}

static void Save_ENGN()
{
	Engine *e;
	FOR_ALL_ENGINES(e) {
		SlSetArrayIndex(e->index);
		SlObject(e, _engine_desc);
	}
}

static void Load_ENGN()
{
	/* As engine data is loaded before engines are initialized we need to load
	 * this information into a temporary array. This is then copied into the
	 * engine pool after processing NewGRFs by CopyTempEngineData(). */
	int index;
	while ((index = SlIterateArray()) != -1) {
		Engine *e = GetTempDataEngine(index);
		SlObject(e, _engine_desc);
	}
}

/**
 * Copy data from temporary engine array into the real engine pool.
 */
void CopyTempEngineData()
{
	Engine *e;
	FOR_ALL_ENGINES(e) {
		if (e->index >= _temp_engine.size()) break;

		const Engine *se = GetTempDataEngine(e->index);
		e->intro_date          = se->intro_date;
		e->age                 = se->age;
		e->reliability         = se->reliability;
		e->reliability_spd_dec = se->reliability_spd_dec;
		e->reliability_start   = se->reliability_start;
		e->reliability_max     = se->reliability_max;
		e->reliability_final   = se->reliability_final;
		e->duration_phase_1    = se->duration_phase_1;
		e->duration_phase_2    = se->duration_phase_2;
		e->duration_phase_3    = se->duration_phase_3;
		e->lifelength          = se->lifelength;
		e->flags               = se->flags;
		e->preview_player_rank = se->preview_player_rank;
		e->preview_wait        = se->preview_wait;
		e->player_avail        = se->player_avail;
		if (se->name != NULL) e->name = strdup(se->name);
	}

	/* Get rid of temporary data */
	_temp_engine.clear();
}

static void Load_ENGS()
{
	/* Load old separate String ID list into a temporary array. This
	 * was always 256 entries. */
	StringID names[256];

	SlArray(names, lengthof(names), SLE_STRINGID);

	/* Copy each string into the temporary engine array. */
	for (EngineID engine = 0; engine < lengthof(names); engine++) {
		Engine *e = GetTempDataEngine(engine);
		e->name = CopyFromOldName(names[engine]);
	}
}

extern const ChunkHandler _engine_chunk_handlers[] = {
	{ 'ENGN', Save_ENGN,     Load_ENGN,     CH_ARRAY          },
	{ 'ENGS', NULL,          Load_ENGS,     CH_RIFF           },
	{ 'ERNW', Save_ERNW,     Load_ERNW,     CH_ARRAY | CH_LAST},
};

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