/* $Id$ */

/*
 * 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 station_sl.cpp Code handling saving and loading of stations. */

#include "../stdafx.h"
#include "../station_base.h"
#include "../waypoint_base.h"
#include "../roadstop_base.h"
#include "../vehicle_base.h"
#include "../newgrf_station.h"

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

/**
 * Update the buoy orders to be waypoint orders.
 * @param o the order 'list' to check.
 */
static void UpdateWaypointOrder(Order *o)
{
	if (!o->IsType(OT_GOTO_STATION)) return;

	const Station *st = Station::Get(o->GetDestination());
	if ((st->had_vehicle_of_type & HVOT_WAYPOINT) == 0) return;

	o->MakeGoToWaypoint(o->GetDestination());
}

/**
 * Perform all steps to upgrade from the old station buoys to the new version
 * that uses waypoints. This includes some old saveload mechanics.
 */
void MoveBuoysToWaypoints()
{
	/* Buoy orders become waypoint orders */
	OrderList *ol;
	FOR_ALL_ORDER_LISTS(ol) {
		VehicleType vt = ol->GetFirstSharedVehicle()->type;
		if (vt != VEH_SHIP && vt != VEH_TRAIN) continue;

		for (Order *o = ol->GetFirstOrder(); o != NULL; o = o->next) UpdateWaypointOrder(o);
	}

	Vehicle *v;
	FOR_ALL_VEHICLES(v) {
		VehicleType vt = v->type;
		if (vt != VEH_SHIP && vt != VEH_TRAIN) continue;

		UpdateWaypointOrder(&v->current_order);
	}

	/* Now make the stations waypoints */
	Station *st;
	FOR_ALL_STATIONS(st) {
		if ((st->had_vehicle_of_type & HVOT_WAYPOINT) == 0) continue;

		StationID index    = st->index;
		TileIndex xy       = st->xy;
		Town *town         = st->town;
		StringID string_id = st->string_id;
		char *name         = st->name;
		st->name           = NULL;
		Date build_date    = st->build_date;
		/* TTDPatch could use "buoys with rail station" for rail waypoints */
		bool train         = st->train_station.tile != INVALID_TILE;
		TileArea train_st  = st->train_station;

		/* Delete the station, so we can make it a real waypoint. */
		delete st;

		/* Stations and waypoints are in the same pool, so if a station
		 * is deleted there must be place for a Waypoint. */
		assert(Waypoint::CanAllocateItem());
		Waypoint *wp   = new (index) Waypoint(xy);
		wp->town       = town;
		wp->string_id  = train ? STR_SV_STNAME_WAYPOINT : STR_SV_STNAME_BUOY;
		wp->name       = name;
		wp->delete_ctr = 0; // Just reset delete counter for once.
		wp->build_date = build_date;
		wp->owner      = train ? GetTileOwner(xy) : OWNER_NONE;

		if (IsInsideBS(string_id, STR_SV_STNAME_BUOY, 9)) wp->town_cn = string_id - STR_SV_STNAME_BUOY;

		if (train) {
			/* When we make a rail waypoint of the station, convert the map as well. */
			TILE_AREA_LOOP(t, train_st) {
				if (!IsTileType(t, MP_STATION) || GetStationIndex(t) != index) continue;

				SB(_m[t].m6, 3, 3, STATION_WAYPOINT);
				wp->rect.BeforeAddTile(t, StationRect::ADD_FORCE);
			}

			wp->train_station = train_st;
			wp->facilities |= FACIL_TRAIN;
		} else if (IsBuoyTile(xy) && GetStationIndex(xy) == index) {
			wp->rect.BeforeAddTile(xy, StationRect::ADD_FORCE);
			wp->facilities |= FACIL_DOCK;
		}
	}
}

void AfterLoadStations()
{
	/* Update the speclists of all stations to point to the currently loaded custom stations. */
	BaseStation *st;
	FOR_ALL_BASE_STATIONS(st) {
		for (uint i = 0; i < st->num_specs; i++) {
			if (st->speclist[i].grfid == 0) continue;

			st->speclist[i].spec = StationClass::GetByGrf(st->speclist[i].grfid, st->speclist[i].localidx, NULL);
		}

		if (Station::IsExpected(st)) {
			Station *sta = Station::From(st);
			for (const RoadStop *rs = sta->bus_stops; rs != NULL; rs = rs->next) sta->bus_station.Add(rs->xy);
			for (const RoadStop *rs = sta->truck_stops; rs != NULL; rs = rs->next) sta->truck_station.Add(rs->xy);
		}

		StationUpdateCachedTriggers(st);
	}
}

/**
 * (Re)building of road stop caches after loading a savegame.
 */
void AfterLoadRoadStops()
{
	/* First construct the drive through entries */
	RoadStop *rs;
	FOR_ALL_ROADSTOPS(rs) {
		if (IsDriveThroughStopTile(rs->xy)) rs->MakeDriveThrough();
	}
	/* And then rebuild the data in those entries */
	FOR_ALL_ROADSTOPS(rs) {
		if (!HasBit(rs->status, RoadStop::RSSFB_BASE_ENTRY)) continue;

		rs->GetEntry(DIAGDIR_NE)->Rebuild(rs);
		rs->GetEntry(DIAGDIR_NW)->Rebuild(rs);
	}
}

static const SaveLoad _roadstop_desc[] = {
	SLE_VAR(RoadStop, xy,           SLE_UINT32),
	SLE_CONDNULL(1, 0, 44),
	SLE_VAR(RoadStop, status,       SLE_UINT8),
	/* Index was saved in some versions, but this is not needed */
	SLE_CONDNULL(4, 0, 8),
	SLE_CONDNULL(2, 0, 44),
	SLE_CONDNULL(1, 0, 25),

	SLE_REF(RoadStop, next,         REF_ROADSTOPS),
	SLE_CONDNULL(2, 0, 44),

	SLE_CONDNULL(4, 0, 24),
	SLE_CONDNULL(1, 25, 25),

	SLE_END()
};

static const SaveLoad _old_station_desc[] = {
	SLE_CONDVAR(Station, xy,                         SLE_FILE_U16 | SLE_VAR_U32,  0, 5),
	SLE_CONDVAR(Station, xy,                         SLE_UINT32,                  6, SL_MAX_VERSION),
	SLE_CONDNULL(4, 0, 5),  ///< bus/lorry tile
	SLE_CONDVAR(Station, train_station.tile,         SLE_FILE_U16 | SLE_VAR_U32,  0, 5),
	SLE_CONDVAR(Station, train_station.tile,         SLE_UINT32,                  6, SL_MAX_VERSION),
	SLE_CONDVAR(Station, airport.tile,               SLE_FILE_U16 | SLE_VAR_U32,  0, 5),
	SLE_CONDVAR(Station, airport.tile,               SLE_UINT32,                  6, SL_MAX_VERSION),
	SLE_CONDVAR(Station, dock_tile,                  SLE_FILE_U16 | SLE_VAR_U32,  0, 5),
	SLE_CONDVAR(Station, dock_tile,                  SLE_UINT32,                  6, SL_MAX_VERSION),
	    SLE_REF(Station, town,                       REF_TOWN),
	    SLE_VAR(Station, train_station.w,            SLE_FILE_U8 | SLE_VAR_U16),
	SLE_CONDVAR(Station, train_station.h,            SLE_FILE_U8 | SLE_VAR_U16,   2, SL_MAX_VERSION),

	SLE_CONDNULL(1, 0, 3),  ///< alpha_order

	    SLE_VAR(Station, string_id,                  SLE_STRINGID),
	SLE_CONDSTR(Station, name,                       SLE_STR | SLF_ALLOW_CONTROL, 0, 84, SL_MAX_VERSION),
	SLE_CONDVAR(Station, indtype,                    SLE_UINT8,                 103, SL_MAX_VERSION),
	SLE_CONDVAR(Station, had_vehicle_of_type,        SLE_FILE_U16 | SLE_VAR_U8,   0, 121),
	SLE_CONDVAR(Station, had_vehicle_of_type,        SLE_UINT8,                 122, SL_MAX_VERSION),

	    SLE_VAR(Station, time_since_load,            SLE_UINT8),
	    SLE_VAR(Station, time_since_unload,          SLE_UINT8),
	    SLE_VAR(Station, delete_ctr,                 SLE_UINT8),
	    SLE_VAR(Station, owner,                      SLE_UINT8),
	    SLE_VAR(Station, facilities,                 SLE_UINT8),
	    SLE_VAR(Station, airport.type,               SLE_UINT8),

	SLE_CONDNULL(2, 0, 5),  ///< Truck/bus stop status
	SLE_CONDNULL(1, 0, 4),  ///< Blocked months

	SLE_CONDVAR(Station, airport.flags,              SLE_VAR_U64 | SLE_FILE_U16,  0,  2),
	SLE_CONDVAR(Station, airport.flags,              SLE_VAR_U64 | SLE_FILE_U32,  3, 45),
	SLE_CONDVAR(Station, airport.flags,              SLE_UINT64,                 46, SL_MAX_VERSION),

	SLE_CONDNULL(2, 0, 25), ///< last-vehicle
	SLE_CONDVAR(Station, last_vehicle_type,          SLE_UINT8,                  26, SL_MAX_VERSION),

	SLE_CONDNULL(2, 3, 25), ///< custom station class and id
	SLE_CONDVAR(Station, build_date,                 SLE_FILE_U16 | SLE_VAR_I32,  3, 30),
	SLE_CONDVAR(Station, build_date,                 SLE_INT32,                  31, SL_MAX_VERSION),

	SLE_CONDREF(Station, bus_stops,                  REF_ROADSTOPS,               6, SL_MAX_VERSION),
	SLE_CONDREF(Station, truck_stops,                REF_ROADSTOPS,               6, SL_MAX_VERSION),

	/* Used by newstations for graphic variations */
	SLE_CONDVAR(Station, random_bits,                SLE_UINT16,                 27, SL_MAX_VERSION),
	SLE_CONDVAR(Station, waiting_triggers,           SLE_UINT8,                  27, SL_MAX_VERSION),
	SLE_CONDVAR(Station, num_specs,                  SLE_UINT8,                  27, SL_MAX_VERSION),

	SLE_CONDLST(Station, loading_vehicles,           REF_VEHICLE,                57, SL_MAX_VERSION),

	/* reserve extra space in savegame here. (currently 32 bytes) */
	SLE_CONDNULL(32, 2, SL_MAX_VERSION),

	SLE_END()
};

static uint16 _waiting_acceptance;
static uint16 _cargo_source;
static uint32 _cargo_source_xy;
static uint8  _cargo_days;
static Money  _cargo_feeder_share;

static const SaveLoad _station_speclist_desc[] = {
	SLE_CONDVAR(StationSpecList, grfid,    SLE_UINT32, 27, SL_MAX_VERSION),
	SLE_CONDVAR(StationSpecList, localidx, SLE_UINT8,  27, SL_MAX_VERSION),

	SLE_END()
};

/**
 * Wrapper function to get the GoodsEntry's internal structure while
 * some of the variables itself are private.
 * @return the saveload description for GoodsEntry.
 */
const SaveLoad *GetGoodsDesc()
{
	static const SaveLoad goods_desc[] = {
		SLEG_CONDVAR(            _waiting_acceptance,  SLE_UINT16,                  0, 67),
		 SLE_CONDVAR(GoodsEntry, acceptance_pickup,    SLE_UINT8,                  68, SL_MAX_VERSION),
		SLE_CONDNULL(2,                                                            51, 67),
		     SLE_VAR(GoodsEntry, time_since_pickup,    SLE_UINT8),
		     SLE_VAR(GoodsEntry, rating,               SLE_UINT8),
		SLEG_CONDVAR(            _cargo_source,        SLE_FILE_U8 | SLE_VAR_U16,   0, 6),
		SLEG_CONDVAR(            _cargo_source,        SLE_UINT16,                  7, 67),
		SLEG_CONDVAR(            _cargo_source_xy,     SLE_UINT32,                 44, 67),
		SLEG_CONDVAR(            _cargo_days,          SLE_UINT8,                   0, 67),
		     SLE_VAR(GoodsEntry, last_speed,           SLE_UINT8),
		     SLE_VAR(GoodsEntry, last_age,             SLE_UINT8),
		SLEG_CONDVAR(            _cargo_feeder_share,  SLE_FILE_U32 | SLE_VAR_I64, 14, 64),
		SLEG_CONDVAR(            _cargo_feeder_share,  SLE_INT64,                  65, 67),
		 SLE_CONDVAR(GoodsEntry, amount_fract,         SLE_UINT8,                 150, SL_MAX_VERSION),
		 SLE_CONDLST(GoodsEntry, cargo.packets,        REF_CARGO_PACKET,           68, SL_MAX_VERSION),
		 SLE_CONDVAR(GoodsEntry, cargo.reserved_count, SLE_UINT,                  181, SL_MAX_VERSION),
		SLE_END()
	};

	return goods_desc;
}


static void Load_STNS()
{
	int index;
	while ((index = SlIterateArray()) != -1) {
		Station *st = new (index) Station();

		SlObject(st, _old_station_desc);

		_waiting_acceptance = 0;

		uint num_cargo = IsSavegameVersionBefore(55) ? 12 : NUM_CARGO;
		for (CargoID i = 0; i < num_cargo; i++) {
			GoodsEntry *ge = &st->goods[i];
			SlObject(ge, GetGoodsDesc());
			if (IsSavegameVersionBefore(68)) {
				SB(ge->acceptance_pickup, GoodsEntry::GES_ACCEPTANCE, 1, HasBit(_waiting_acceptance, 15));
				if (GB(_waiting_acceptance, 0, 12) != 0) {
					/* In old versions, enroute_from used 0xFF as INVALID_STATION */
					StationID source = (IsSavegameVersionBefore(7) && _cargo_source == 0xFF) ? INVALID_STATION : _cargo_source;

					/* Make sure we can allocate the CargoPacket. This is safe
					 * as there can only be ~64k stations and 32 cargoes in these
					 * savegame versions. As the CargoPacketPool has more than
					 * 16 million entries; it fits by an order of magnitude. */
					assert(CargoPacket::CanAllocateItem());
					ge->cargo.Append(new CargoPacket(GB(_waiting_acceptance, 0, 12), _cargo_days, source, _cargo_source_xy, _cargo_source_xy, _cargo_feeder_share));
					SB(ge->acceptance_pickup, GoodsEntry::GES_PICKUP, 1, 1);
				}
			}
		}

		if (st->num_specs != 0) {
			/* Allocate speclist memory when loading a game */
			st->speclist = CallocT<StationSpecList>(st->num_specs);
			for (uint i = 0; i < st->num_specs; i++) {
				SlObject(&st->speclist[i], _station_speclist_desc);
			}
		}
	}
}

static void Ptrs_STNS()
{
	/* Don't run when savegame version is higher than or equal to 123. */
	if (!IsSavegameVersionBefore(123)) return;

	Station *st;
	FOR_ALL_STATIONS(st) {
		if (!IsSavegameVersionBefore(68)) {
			for (CargoID i = 0; i < NUM_CARGO; i++) {
				GoodsEntry *ge = &st->goods[i];
				SlObject(ge, GetGoodsDesc());
			}
		}
		SlObject(st, _old_station_desc);
	}
}


static const SaveLoad _base_station_desc[] = {
	      SLE_VAR(BaseStation, xy,                     SLE_UINT32),
	      SLE_REF(BaseStation, town,                   REF_TOWN),
	      SLE_VAR(BaseStation, string_id,              SLE_STRINGID),
	      SLE_STR(BaseStation, name,                   SLE_STR | SLF_ALLOW_CONTROL, 0),
	      SLE_VAR(BaseStation, delete_ctr,             SLE_UINT8),
	      SLE_VAR(BaseStation, owner,                  SLE_UINT8),
	      SLE_VAR(BaseStation, facilities,             SLE_UINT8),
	      SLE_VAR(BaseStation, build_date,             SLE_INT32),

	/* Used by newstations for graphic variations */
	      SLE_VAR(BaseStation, random_bits,            SLE_UINT16),
	      SLE_VAR(BaseStation, waiting_triggers,       SLE_UINT8),
	      SLE_VAR(BaseStation, num_specs,              SLE_UINT8),

	      SLE_END()
};

static OldPersistentStorage _old_st_persistent_storage;

static const SaveLoad _station_desc[] = {
	SLE_WRITEBYTE(Station, facilities,                 FACIL_NONE),
	SLE_ST_INCLUDE(),

	      SLE_VAR(Station, train_station.tile,         SLE_UINT32),
	      SLE_VAR(Station, train_station.w,            SLE_FILE_U8 | SLE_VAR_U16),
	      SLE_VAR(Station, train_station.h,            SLE_FILE_U8 | SLE_VAR_U16),

	      SLE_REF(Station, bus_stops,                  REF_ROADSTOPS),
	      SLE_REF(Station, truck_stops,                REF_ROADSTOPS),
	      SLE_VAR(Station, dock_tile,                  SLE_UINT32),
	      SLE_VAR(Station, airport.tile,               SLE_UINT32),
	  SLE_CONDVAR(Station, airport.w,                  SLE_FILE_U8 | SLE_VAR_U16, 140, SL_MAX_VERSION),
	  SLE_CONDVAR(Station, airport.h,                  SLE_FILE_U8 | SLE_VAR_U16, 140, SL_MAX_VERSION),
	      SLE_VAR(Station, airport.type,               SLE_UINT8),
	  SLE_CONDVAR(Station, airport.layout,             SLE_UINT8,                 145, SL_MAX_VERSION),
	      SLE_VAR(Station, airport.flags,              SLE_UINT64),
	  SLE_CONDVAR(Station, airport.rotation,           SLE_UINT8,                 145, SL_MAX_VERSION),
	 SLEG_CONDARR(_old_st_persistent_storage.storage,  SLE_UINT32, 16,            145, 160),
	  SLE_CONDREF(Station, airport.psa,                REF_STORAGE,               161, SL_MAX_VERSION),

	      SLE_VAR(Station, indtype,                    SLE_UINT8),

	      SLE_VAR(Station, time_since_load,            SLE_UINT8),
	      SLE_VAR(Station, time_since_unload,          SLE_UINT8),
	      SLE_VAR(Station, last_vehicle_type,          SLE_UINT8),
	      SLE_VAR(Station, had_vehicle_of_type,        SLE_UINT8),
	      SLE_LST(Station, loading_vehicles,           REF_VEHICLE),
	  SLE_CONDVAR(Station, always_accepted,            SLE_UINT32, 127, SL_MAX_VERSION),

	      SLE_END()
};

static const SaveLoad _waypoint_desc[] = {
	SLE_WRITEBYTE(Waypoint, facilities,                FACIL_WAYPOINT),
	SLE_ST_INCLUDE(),

	      SLE_VAR(Waypoint, town_cn,                   SLE_UINT16),

	  SLE_CONDVAR(Waypoint, train_station.tile,        SLE_UINT32,                  124, SL_MAX_VERSION),
	  SLE_CONDVAR(Waypoint, train_station.w,           SLE_FILE_U8 | SLE_VAR_U16,   124, SL_MAX_VERSION),
	  SLE_CONDVAR(Waypoint, train_station.h,           SLE_FILE_U8 | SLE_VAR_U16,   124, SL_MAX_VERSION),

	      SLE_END()
};

/**
 * Get the base station description to be used for SL_ST_INCLUDE
 * @return the base station description.
 */
const SaveLoad *GetBaseStationDescription()
{
	return _base_station_desc;
}

static void RealSave_STNN(BaseStation *bst)
{
	bool waypoint = (bst->facilities & FACIL_WAYPOINT) != 0;
	SlObject(bst, waypoint ? _waypoint_desc : _station_desc);

	if (!waypoint) {
		Station *st = Station::From(bst);
		for (CargoID i = 0; i < NUM_CARGO; i++) {
			SlObject(&st->goods[i], GetGoodsDesc());
		}
	}

	for (uint i = 0; i < bst->num_specs; i++) {
		SlObject(&bst->speclist[i], _station_speclist_desc);
	}
}

static void Save_STNN()
{
	BaseStation *st;
	/* Write the stations */
	FOR_ALL_BASE_STATIONS(st) {
		SlSetArrayIndex(st->index);
		SlAutolength((AutolengthProc*)RealSave_STNN, st);
	}
}

static void Load_STNN()
{
	int index;

	while ((index = SlIterateArray()) != -1) {
		bool waypoint = (SlReadByte() & FACIL_WAYPOINT) != 0;

		BaseStation *bst = waypoint ? (BaseStation *)new (index) Waypoint() : new (index) Station();
		SlObject(bst, waypoint ? _waypoint_desc : _station_desc);

		if (!waypoint) {
			Station *st = Station::From(bst);

			/* Before savegame version 161, persistent storages were not stored in a pool. */
			if (IsSavegameVersionBefore(161) && !IsSavegameVersionBefore(145) && st->facilities & FACIL_AIRPORT) {
				/* Store the old persistent storage. The GRFID will be added later. */
				assert(PersistentStorage::CanAllocateItem());
				st->airport.psa = new PersistentStorage(0);
				memcpy(st->airport.psa->storage, _old_st_persistent_storage.storage, sizeof(st->airport.psa->storage));
			}

			for (CargoID i = 0; i < NUM_CARGO; i++) {
				SlObject(&st->goods[i], GetGoodsDesc());
			}
		}

		if (bst->num_specs != 0) {
			/* Allocate speclist memory when loading a game */
			bst->speclist = CallocT<StationSpecList>(bst->num_specs);
			for (uint i = 0; i < bst->num_specs; i++) {
				SlObject(&bst->speclist[i], _station_speclist_desc);
			}
		}
	}
}

static void Ptrs_STNN()
{
	/* Don't run when savegame version lower than 123. */
	if (IsSavegameVersionBefore(123)) return;

	Station *st;
	FOR_ALL_STATIONS(st) {
		for (CargoID i = 0; i < NUM_CARGO; i++) {
			GoodsEntry *ge = &st->goods[i];
			SlObject(ge, GetGoodsDesc());
		}
		SlObject(st, _station_desc);
	}

	Waypoint *wp;
	FOR_ALL_WAYPOINTS(wp) {
		SlObject(wp, _waypoint_desc);
	}
}

static void Save_ROADSTOP()
{
	RoadStop *rs;

	FOR_ALL_ROADSTOPS(rs) {
		SlSetArrayIndex(rs->index);
		SlObject(rs, _roadstop_desc);
	}
}

static void Load_ROADSTOP()
{
	int index;

	while ((index = SlIterateArray()) != -1) {
		RoadStop *rs = new (index) RoadStop(INVALID_TILE);

		SlObject(rs, _roadstop_desc);
	}
}

static void Ptrs_ROADSTOP()
{
	RoadStop *rs;
	FOR_ALL_ROADSTOPS(rs) {
		SlObject(rs, _roadstop_desc);
	}
}

extern const ChunkHandler _station_chunk_handlers[] = {
	{ 'STNS', NULL,          Load_STNS,     Ptrs_STNS,     NULL, CH_ARRAY },
	{ 'STNN', Save_STNN,     Load_STNN,     Ptrs_STNN,     NULL, CH_ARRAY },
	{ 'ROAD', Save_ROADSTOP, Load_ROADSTOP, Ptrs_ROADSTOP, NULL, CH_ARRAY | CH_LAST},
};