1 /*
2  * This file is part of OpenTTD.
3  * 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.
4  * 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.
5  * 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/>.
6  */
7 
8 /** @file waypoint_sl.cpp Code handling saving and loading of waypoints */
9 
10 #include "../stdafx.h"
11 #include "../waypoint_base.h"
12 #include "../debug.h"
13 #include "../newgrf_station.h"
14 #include "../vehicle_base.h"
15 #include "../town.h"
16 #include "../newgrf.h"
17 
18 #include "table/strings.h"
19 
20 #include "saveload_internal.h"
21 
22 #include "../safeguards.h"
23 
24 /** Helper structure to convert from the old waypoint system. */
25 struct OldWaypoint {
26 	size_t index;
27 	TileIndex xy;
28 	TownID town_index;
29 	Town *town;
30 	uint16 town_cn;
31 	StringID string_id;
32 	std::string name;
33 	uint8 delete_ctr;
34 	Date build_date;
35 	uint8 localidx;
36 	uint32 grfid;
37 	const StationSpec *spec;
38 	Owner owner;
39 
40 	size_t new_index;
41 };
42 
43 /** Temporary array with old waypoints. */
44 static std::vector<OldWaypoint> _old_waypoints;
45 
46 /**
47  * Update the waypoint orders to get the new waypoint ID.
48  * @param o the order 'list' to check.
49  */
UpdateWaypointOrder(Order * o)50 static void UpdateWaypointOrder(Order *o)
51 {
52 	if (!o->IsType(OT_GOTO_WAYPOINT)) return;
53 
54 	for (OldWaypoint &wp : _old_waypoints) {
55 		if (wp.index != o->GetDestination()) continue;
56 
57 		o->SetDestination((DestinationID)wp.new_index);
58 		return;
59 	}
60 }
61 
62 /**
63  * Perform all steps to upgrade from the old waypoints to the new version
64  * that uses station. This includes some old saveload mechanics.
65  */
MoveWaypointsToBaseStations()66 void MoveWaypointsToBaseStations()
67 {
68 	/* In version 17, ground type is moved from m2 to m4 for depots and
69 	 * waypoints to make way for storing the index in m2. The custom graphics
70 	 * id which was stored in m4 is now saved as a grf/id reference in the
71 	 * waypoint struct. */
72 	if (IsSavegameVersionBefore(SLV_17)) {
73 		for (OldWaypoint &wp : _old_waypoints) {
74 			if (wp.delete_ctr != 0) continue; // The waypoint was deleted
75 
76 			/* Waypoint indices were not added to the map prior to this. */
77 			_m[wp.xy].m2 = (StationID)wp.index;
78 
79 			if (HasBit(_m[wp.xy].m3, 4)) {
80 				wp.spec = StationClass::Get(STAT_CLASS_WAYP)->GetSpec(_m[wp.xy].m4 + 1);
81 			}
82 		}
83 	} else {
84 		/* As of version 17, we recalculate the custom graphic ID of waypoints
85 		 * from the GRF ID / station index. */
86 		for (OldWaypoint &wp : _old_waypoints) {
87 			StationClass* stclass = StationClass::Get(STAT_CLASS_WAYP);
88 			for (uint i = 0; i < stclass->GetSpecCount(); i++) {
89 				const StationSpec *statspec = stclass->GetSpec(i);
90 				if (statspec != nullptr && statspec->grf_prop.grffile->grfid == wp.grfid && statspec->grf_prop.local_id == wp.localidx) {
91 					wp.spec = statspec;
92 					break;
93 				}
94 			}
95 		}
96 	}
97 
98 	if (!Waypoint::CanAllocateItem(_old_waypoints.size())) SlError(STR_ERROR_TOO_MANY_STATIONS_LOADING);
99 
100 	/* All saveload conversions have been done. Create the new waypoints! */
101 	for (OldWaypoint &wp : _old_waypoints) {
102 		TileIndex t = wp.xy;
103 		/* Sometimes waypoint (sign) locations became disconnected from their actual location in
104 		 * the map array. If this is the case, try to locate the actual location in the map array */
105 		if (!IsTileType(t, MP_RAILWAY) || GetRailTileType(t) != 2 /* RAIL_TILE_WAYPOINT */ || _m[t].m2 != wp.index) {
106 			Debug(sl, 0, "Found waypoint tile {} with invalid position", t);
107 			for (t = 0; t < MapSize(); t++) {
108 				if (IsTileType(t, MP_RAILWAY) && GetRailTileType(t) == 2 /* RAIL_TILE_WAYPOINT */ && _m[t].m2 == wp.index) {
109 					Debug(sl, 0, "Found actual waypoint position at {}", t);
110 					break;
111 				}
112 			}
113 		}
114 		if (t == MapSize()) {
115 			SlErrorCorrupt("Waypoint with invalid tile");
116 		}
117 
118 		Waypoint *new_wp = new Waypoint(t);
119 		new_wp->town       = wp.town;
120 		new_wp->town_cn    = wp.town_cn;
121 		new_wp->name       = wp.name;
122 		new_wp->delete_ctr = 0; // Just reset delete counter for once.
123 		new_wp->build_date = wp.build_date;
124 		new_wp->owner      = wp.owner;
125 		new_wp->string_id  = STR_SV_STNAME_WAYPOINT;
126 
127 		/* The tile might've been reserved! */
128 		bool reserved = !IsSavegameVersionBefore(SLV_100) && HasBit(_m[t].m5, 4);
129 
130 		/* The tile really has our waypoint, so reassign the map array */
131 		MakeRailWaypoint(t, GetTileOwner(t), new_wp->index, (Axis)GB(_m[t].m5, 0, 1), 0, GetRailType(t));
132 		new_wp->facilities |= FACIL_TRAIN;
133 		new_wp->owner = GetTileOwner(t);
134 
135 		SetRailStationReservation(t, reserved);
136 
137 		if (wp.spec != nullptr) {
138 			SetCustomStationSpecIndex(t, AllocateSpecToStation(wp.spec, new_wp, true));
139 		}
140 		new_wp->rect.BeforeAddTile(t, StationRect::ADD_FORCE);
141 
142 		wp.new_index = new_wp->index;
143 	}
144 
145 	/* Update the orders of vehicles */
146 	for (OrderList *ol : OrderList::Iterate()) {
147 		if (ol->GetFirstSharedVehicle()->type != VEH_TRAIN) continue;
148 
149 		for (Order *o = ol->GetFirstOrder(); o != nullptr; o = o->next) UpdateWaypointOrder(o);
150 	}
151 
152 	for (Vehicle *v : Vehicle::Iterate()) {
153 		if (v->type != VEH_TRAIN) continue;
154 
155 		UpdateWaypointOrder(&v->current_order);
156 	}
157 
158 	ResetOldWaypoints();
159 }
160 
ResetOldWaypoints()161 void ResetOldWaypoints()
162 {
163 	_old_waypoints.clear();
164 	_old_waypoints.shrink_to_fit();
165 }
166 
167 static const SaveLoad _old_waypoint_desc[] = {
168 	SLE_CONDVAR(OldWaypoint, xy,         SLE_FILE_U16 | SLE_VAR_U32,  SL_MIN_VERSION, SLV_6),
169 	SLE_CONDVAR(OldWaypoint, xy,         SLE_UINT32,                  SLV_6, SL_MAX_VERSION),
170 	SLE_CONDVAR(OldWaypoint, town_index, SLE_UINT16,                 SLV_12, SLV_122),
171 	SLE_CONDREF(OldWaypoint, town,       REF_TOWN,                  SLV_122, SL_MAX_VERSION),
172 	SLE_CONDVAR(OldWaypoint, town_cn,    SLE_FILE_U8 | SLE_VAR_U16,  SLV_12, SLV_89),
173 	SLE_CONDVAR(OldWaypoint, town_cn,    SLE_UINT16,                 SLV_89, SL_MAX_VERSION),
174 	SLE_CONDVAR(OldWaypoint, string_id,  SLE_STRINGID,                SL_MIN_VERSION, SLV_84),
175 	SLE_CONDSSTR(OldWaypoint, name,      SLE_STR,                    SLV_84, SL_MAX_VERSION),
176 	    SLE_VAR(OldWaypoint, delete_ctr, SLE_UINT8),
177 
178 	SLE_CONDVAR(OldWaypoint, build_date, SLE_FILE_U16 | SLE_VAR_I32,  SLV_3, SLV_31),
179 	SLE_CONDVAR(OldWaypoint, build_date, SLE_INT32,                  SLV_31, SL_MAX_VERSION),
180 	SLE_CONDVAR(OldWaypoint, localidx,   SLE_UINT8,                   SLV_3, SL_MAX_VERSION),
181 	SLE_CONDVAR(OldWaypoint, grfid,      SLE_UINT32,                 SLV_17, SL_MAX_VERSION),
182 	SLE_CONDVAR(OldWaypoint, owner,      SLE_UINT8,                 SLV_101, SL_MAX_VERSION),
183 };
184 
185 struct CHKPChunkHandler : ChunkHandler {
CHKPChunkHandlerCHKPChunkHandler186 	CHKPChunkHandler() : ChunkHandler('CHKP', CH_READONLY) {}
187 
LoadCHKPChunkHandler188 	void Load() const override
189 	{
190 		/* Precaution for when loading failed and it didn't get cleared */
191 		ResetOldWaypoints();
192 
193 		int index;
194 
195 		while ((index = SlIterateArray()) != -1) {
196 			OldWaypoint *wp = &_old_waypoints.emplace_back();
197 
198 			wp->index = index;
199 			SlObject(wp, _old_waypoint_desc);
200 		}
201 	}
202 
FixPointersCHKPChunkHandler203 	void FixPointers() const override
204 	{
205 		for (OldWaypoint &wp : _old_waypoints) {
206 			SlObject(&wp, _old_waypoint_desc);
207 
208 			if (IsSavegameVersionBefore(SLV_12)) {
209 				wp.town_cn = (wp.string_id & 0xC000) == 0xC000 ? (wp.string_id >> 8) & 0x3F : 0;
210 				wp.town = ClosestTownFromTile(wp.xy, UINT_MAX);
211 			} else if (IsSavegameVersionBefore(SLV_122)) {
212 				/* Only for versions 12 .. 122 */
213 				if (!Town::IsValidID(wp.town_index)) {
214 					/* Upon a corrupted waypoint we'll likely get here. The next step will be to
215 					 * loop over all Ptrs procs to nullptr the pointers. However, we don't know
216 					 * whether we're in the nullptr or "normal" Ptrs proc. So just clear the list
217 					 * of old waypoints we constructed and then this waypoint (and the other
218 					 * possibly corrupt ones) will not be queried in the nullptr Ptrs proc run. */
219 					_old_waypoints.clear();
220 					SlErrorCorrupt("Referencing invalid Town");
221 				}
222 				wp.town = Town::Get(wp.town_index);
223 			}
224 			if (IsSavegameVersionBefore(SLV_84)) {
225 				wp.name = CopyFromOldName(wp.string_id);
226 			}
227 		}
228 	}
229 };
230 
231 static const CHKPChunkHandler CHKP;
232 static const ChunkHandlerRef waypoint_chunk_handlers[] = {
233 	CHKP,
234 };
235 
236 extern const ChunkHandlerTable _waypoint_chunk_handlers(waypoint_chunk_handlers);
237