Files @ r28616:1df48a6fd940
Branch filter:

Location: cpp/openttd-patchpack/source/src/gamelog.cpp

glx22
Fix 48b6b18: Increase MAX_VALUATE_OPS to match the previous limit
  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
/*
 * 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 gamelog.cpp Definition of functions used for logging of fundamental changes to the game */

#include "stdafx.h"
#include "saveload/saveload.h"
#include "string_func.h"
#include "settings_type.h"
#include "gamelog_internal.h"
#include "console_func.h"
#include "debug.h"
#include "timer/timer_game_calendar.h"
#include "timer/timer_game_tick.h"
#include "rev.h"

#include "safeguards.h"

extern const SaveLoadVersion SAVEGAME_VERSION;  ///< current savegame version

extern SavegameType _savegame_type; ///< type of savegame we are loading

extern uint32_t _ttdp_version;        ///< version of TTDP savegame (if applicable)
extern SaveLoadVersion _sl_version; ///< the major savegame version identifier
extern byte   _sl_minor_version;    ///< the minor savegame version, DO NOT USE!

Gamelog _gamelog; ///< Gamelog instance

Gamelog::Gamelog()
{
	this->data = std::make_unique<GamelogInternalData>();
	this->action_type = GLAT_NONE;
	this->current_action = nullptr;
}

Gamelog::~Gamelog()
{
}

/**
 * Return the revision string for the current client version, for use in gamelog.
 */
static std::string GetGamelogRevisionString()
{
	if (IsReleasedVersion()) {
		return _openttd_revision;
	}

	/* Prefix character indication revision status */
	assert(_openttd_revision_modified < 3);
	return fmt::format("{}{}",
			"gum"[_openttd_revision_modified], // g = "git", u = "unknown", m = "modified"
			_openttd_revision_hash);
}

/**
 * Stores information about new action, but doesn't allocate it
 * Action is allocated only when there is at least one change
 * @param at type of action
 */
void Gamelog::StartAction(GamelogActionType at)
{
	assert(this->action_type == GLAT_NONE); // do not allow starting new action without stopping the previous first
	this->action_type = at;
}

/**
 * Stops logging of any changes
 */
void Gamelog::StopAction()
{
	assert(this->action_type != GLAT_NONE); // nobody should try to stop if there is no action in progress

	bool print = this->current_action != nullptr;

	this->current_action = nullptr;
	this->action_type = GLAT_NONE;

	if (print) this->PrintDebug(5);
}

void Gamelog::StopAnyAction()
{
	if (this->action_type != GLAT_NONE) this->StopAction();
}

/**
 * Resets and frees all memory allocated - used before loading or starting a new game
 */
void Gamelog::Reset()
{
	assert(this->action_type == GLAT_NONE);
	this->data->action.clear();
	this->current_action  = nullptr;
}

/**
 * Adds the GRF ID, checksum and filename if found to the output iterator
 * @param output_iterator The iterator to add the GRF info to.
 * @param last The end of the buffer
 * @param grfid GRF ID
 * @param md5sum array of md5sum to print, if known
 * @param gc GrfConfig, if known
 */
static void AddGrfInfo(std::back_insert_iterator<std::string> &output_iterator, uint32_t grfid, const MD5Hash *md5sum, const GRFConfig *gc)
{
	if (md5sum != nullptr) {
		fmt::format_to(output_iterator, "GRF ID {:08X}, checksum {}", BSWAP32(grfid), FormatArrayAsHex(*md5sum));
	} else {
		fmt::format_to(output_iterator, "GRF ID {:08X}", BSWAP32(grfid));
	}

	if (gc != nullptr) {
		fmt::format_to(output_iterator, ", filename: {} (md5sum matches)", gc->filename);
	} else {
		gc = FindGRFConfig(grfid, FGCM_ANY);
		if (gc != nullptr) {
			fmt::format_to(output_iterator, ", filename: {} (matches GRFID only)", gc->filename);
		} else {
			fmt::format_to(output_iterator, ", unknown GRF");
		}
	}
}


/** Text messages for various logged actions */
static const char * const la_text[] = {
	"new game started",
	"game loaded",
	"GRF config changed",
	"cheat was used",
	"settings changed",
	"GRF bug triggered",
	"emergency savegame",
};

static_assert(lengthof(la_text) == GLAT_END);

/**
 * Prints active gamelog
 * @param proc the procedure to draw with
 */
void Gamelog::Print(std::function<void(const std::string &)> proc)
{
	GrfIDMapping grf_names;

	proc("---- gamelog start ----");

	for (const LoggedAction &la : this->data->action) {
		assert(la.at < GLAT_END);

		proc(fmt::format("Tick {}: {}", la.tick, la_text[la.at]));

		for (auto &lc : la.change) {
			std::string message;
			auto output_iterator = std::back_inserter(message);
			lc->FormatTo(output_iterator, grf_names, la.at);

			proc(message);
		}
	}

	proc("---- gamelog end ----");
}


/* virtual */ void LoggedChangeMode::FormatTo(std::back_insert_iterator<std::string> &output_iterator, GrfIDMapping &, GamelogActionType)
{
	/* Changing landscape, or going from scenario editor to game or back. */
	fmt::format_to(output_iterator, "New game mode: {} landscape: {}", this->mode, this->landscape);
}

/* virtual */ void LoggedChangeRevision::FormatTo(std::back_insert_iterator<std::string> &output_iterator, GrfIDMapping &, GamelogActionType)
{
	/* The game was loaded in a diffferent version than before. */
	fmt::format_to(output_iterator, "Revision text changed to {}, savegame version {}, ",
		this->text, this->slver);

	switch (this->modified) {
		case 0: fmt::format_to(output_iterator, "not "); break;
		case 1: fmt::format_to(output_iterator, "maybe "); break;
		default: break;
	}

	fmt::format_to(output_iterator, "modified, _openttd_newgrf_version = 0x{:08x}", this->newgrf);
}

/* virtual */ void LoggedChangeOldVersion::FormatTo(std::back_insert_iterator<std::string> &output_iterator, GrfIDMapping &, GamelogActionType)
{
	/* The game was loaded from before 0.7.0-beta1. */
	fmt::format_to(output_iterator, "Conversion from ");
	switch (this->type) {
		default: NOT_REACHED();
		case SGT_OTTD:
			fmt::format_to(output_iterator, "OTTD savegame without gamelog: version {}, {}",
				GB(this->version, 8, 16), GB(this->version, 0, 8));
			break;

		case SGT_TTO:
			fmt::format_to(output_iterator, "TTO savegame");
			break;

		case SGT_TTD:
			fmt::format_to(output_iterator, "TTD savegame");
			break;

		case SGT_TTDP1:
		case SGT_TTDP2:
			fmt::format_to(output_iterator, "TTDP savegame, {} format",
				this->type == SGT_TTDP1 ? "old" : "new");
			if (this->version != 0) {
				fmt::format_to(output_iterator, ", TTDP version {}.{}.{}.{}",
					GB(this->version, 24, 8), GB(this->version, 20, 4),
					GB(this->version, 16, 4), GB(this->version, 0, 16));
			}
			break;
	}
}

/* virtual */ void LoggedChangeSettingChanged::FormatTo(std::back_insert_iterator<std::string> &output_iterator, GrfIDMapping &, GamelogActionType)
{
	/* A setting with the SF_NO_NETWORK flag got changed; these settings usually affect NewGRFs, such as road side or wagon speed limits. */
	fmt::format_to(output_iterator, "Setting changed: {} : {} -> {}", this->name, this->oldval, this->newval);
}

/* virtual */ void LoggedChangeGRFAdd::FormatTo(std::back_insert_iterator<std::string> &output_iterator, GrfIDMapping &grf_names, GamelogActionType)
{
	/* A NewGRF got added to the game, either at the start of the game (never an issue), or later on when it could be an issue. */
	const GRFConfig *gc = FindGRFConfig(this->grfid, FGCM_EXACT, &this->md5sum);
	fmt::format_to(output_iterator, "Added NewGRF: ");
	AddGrfInfo(output_iterator, this->grfid, &this->md5sum, gc);
	auto gm = grf_names.find(this->grfid);
	if (gm != grf_names.end() && !gm->second.was_missing) fmt::format_to(output_iterator, ". Gamelog inconsistency: GrfID was already added!");
	grf_names[this->grfid] = gc;
}

/* virtual */ void LoggedChangeGRFRemoved::FormatTo(std::back_insert_iterator<std::string> &output_iterator, GrfIDMapping &grf_names, GamelogActionType action_type)
{
	/* A NewGRF got removed from the game, either manually or by it missing when loading the game. */
	auto gm = grf_names.find(this->grfid);
	if (action_type == GLAT_LOAD) {
		fmt::format_to(output_iterator, "Missing NewGRF: ");
	} else {
		fmt::format_to(output_iterator, "Removed NewGRF: ");
	}
	AddGrfInfo(output_iterator, this->grfid, nullptr, gm != grf_names.end() ? gm->second.gc : nullptr);
	if (gm == grf_names.end()) {
		fmt::format_to(output_iterator, ". Gamelog inconsistency: GrfID was never added!");
	} else {
		if (action_type == GLAT_LOAD) {
			/* Missing grfs on load are not removed from the configuration */
			gm->second.was_missing = true;
		} else {
			grf_names.erase(gm);
		}
	}
}

/* virtual */ void LoggedChangeGRFChanged::FormatTo(std::back_insert_iterator<std::string> &output_iterator, GrfIDMapping &grf_names, GamelogActionType)
{
	/* Another version of the same NewGRF got loaded. */
	const GRFConfig *gc = FindGRFConfig(this->grfid, FGCM_EXACT, &this->md5sum);
	fmt::format_to(output_iterator, "Compatible NewGRF loaded: ");
	AddGrfInfo(output_iterator, this->grfid, &this->md5sum, gc);
	if (grf_names.count(this->grfid) == 0) fmt::format_to(output_iterator, ". Gamelog inconsistency: GrfID was never added!");
	grf_names[this->grfid] = gc;
}

/* virtual */ void LoggedChangeGRFParameterChanged::FormatTo(std::back_insert_iterator<std::string> &output_iterator, GrfIDMapping &grf_names, GamelogActionType)
{
	/* A parameter of a NewGRF got changed after the game was started. */
	auto gm = grf_names.find(this->grfid);
	fmt::format_to(output_iterator, "GRF parameter changed: ");
	AddGrfInfo(output_iterator, this->grfid, nullptr, gm != grf_names.end() ? gm->second.gc : nullptr);
	if (gm == grf_names.end()) fmt::format_to(output_iterator, ". Gamelog inconsistency: GrfID was never added!");
}

/* virtual */ void LoggedChangeGRFMoved::FormatTo(std::back_insert_iterator<std::string> &output_iterator, GrfIDMapping &grf_names, GamelogActionType)
{
	/* The order of NewGRFs got changed, which might cause some other NewGRFs to behave differently. */
	auto gm = grf_names.find(this->grfid);
	fmt::format_to(output_iterator, "GRF order changed: {:08X} moved {} places {}",
		BSWAP32(this->grfid), abs(this->offset), this->offset >= 0 ? "down" : "up" );
	AddGrfInfo(output_iterator, this->grfid, nullptr, gm != grf_names.end() ? gm->second.gc : nullptr);
	if (gm == grf_names.end()) fmt::format_to(output_iterator, ". Gamelog inconsistency: GrfID was never added!");
}

/* virtual */ void LoggedChangeGRFBug::FormatTo(std::back_insert_iterator<std::string> &output_iterator, GrfIDMapping &grf_names, GamelogActionType)
{
	/* A specific bug in a NewGRF, that could cause wide spread problems, has been noted during the execution of the game. */
	auto gm = grf_names.find(this->grfid);
	assert(this->bug == GBUG_VEH_LENGTH);

	fmt::format_to(output_iterator, "Rail vehicle changes length outside a depot: GRF ID {:08X}, internal ID 0x{:X}", BSWAP32(this->grfid), this->data);
	AddGrfInfo(output_iterator, this->grfid, nullptr, gm != grf_names.end() ? gm->second.gc : nullptr);
	if (gm == grf_names.end()) fmt::format_to(output_iterator, ". Gamelog inconsistency: GrfID was never added!");
}

/* virtual */ void LoggedChangeEmergencySave::FormatTo(std::back_insert_iterator<std::string> &, GrfIDMapping &, GamelogActionType)
{
	/* At one point the savegame was made during the handling of a game crash.
	 * The generic code already mentioned the emergency savegame, and there is no extra information to log. */
}

/** Print the gamelog data to the console. */
void Gamelog::PrintConsole()
{
	this->Print([](const std::string &s) {
		IConsolePrint(CC_WARNING, s);
	});
}

/**
 * Prints gamelog to debug output. Code is executed even when
 * there will be no output. It is called very seldom, so it
 * doesn't matter that much. At least it gives more uniform code...
 * @param level debug level we need to print stuff
 */
void Gamelog::PrintDebug(int level)
{
	this->Print([level](const std::string &s) {
		Debug(gamelog, level, "{}", s);
	});
}


/**
 * Allocates a new LoggedAction if needed, and add the change when action is active.
 * @param change The actual change.
 */
void Gamelog::Change(std::unique_ptr<LoggedChange> &&change)
{
	if (this->current_action == nullptr) {
		if (this->action_type == GLAT_NONE) return;

		this->current_action = &this->data->action.emplace_back();
		this->current_action->at = this->action_type;
		this->current_action->tick = TimerGameTick::counter;
	}

	this->current_action->change.push_back(std::move(change));
}


/**
 * Logs a emergency savegame
 */
void Gamelog::Emergency()
{
	/* Terminate any active action */
	if (this->action_type != GLAT_NONE) this->StopAction();
	this->StartAction(GLAT_EMERGENCY);
	this->Change(std::make_unique<LoggedChangeEmergencySave>());
	this->StopAction();
}

/**
 * Finds out if current game is a loaded emergency savegame.
 */
bool Gamelog::TestEmergency()
{
	for (const LoggedAction &la : this->data->action) {
		for (const auto &lc : la.change) {
			if (lc->ct == GLCT_EMERGENCY) return true;
		}
	}

	return false;
}

/**
 * Logs a change in game revision
 */
void Gamelog::Revision()
{
	assert(this->action_type == GLAT_START || this->action_type == GLAT_LOAD);

	this->Change(std::make_unique<LoggedChangeRevision>(
		GetGamelogRevisionString(), _openttd_newgrf_version, SAVEGAME_VERSION, _openttd_revision_modified));
}

/**
 * Logs a change in game mode (scenario editor or game)
 */
void Gamelog::Mode()
{
	assert(this->action_type == GLAT_START || this->action_type == GLAT_LOAD || this->action_type == GLAT_CHEAT);

	this->Change(std::make_unique<LoggedChangeMode>(_game_mode, _settings_game.game_creation.landscape));
}

/**
 * Logs loading from savegame without gamelog
 */
void Gamelog::Oldver()
{
	assert(this->action_type == GLAT_LOAD);

	this->Change(std::make_unique<LoggedChangeOldVersion>(_savegame_type,
		(_savegame_type == SGT_OTTD ? ((uint32_t)_sl_version << 8 | _sl_minor_version) : _ttdp_version)));
}

/**
 * Logs change in game settings. Only non-networksafe settings are logged
 * @param name setting name
 * @param oldval old setting value
 * @param newval new setting value
 */
void Gamelog::Setting(const std::string &name, int32_t oldval, int32_t newval)
{
	assert(this->action_type == GLAT_SETTING);

	this->Change(std::make_unique<LoggedChangeSettingChanged>(name, oldval, newval));
}


/**
 * Finds out if current revision is different than last revision stored in the savegame.
 * Appends GLCT_REVISION when the revision string changed
 */
void Gamelog::TestRevision()
{
	const LoggedChangeRevision *rev = nullptr;

	for (const LoggedAction &la : this->data->action) {
		for (const auto &lc : la.change) {
			if (lc->ct == GLCT_REVISION) rev = static_cast<const LoggedChangeRevision *>(lc.get());
		}
	}

	if (rev == nullptr || rev->text != GetGamelogRevisionString() ||
			rev->modified != _openttd_revision_modified ||
			rev->newgrf != _openttd_newgrf_version) {
		this->Revision();
	}
}

/**
 * Finds last stored game mode or landscape.
 * Any change is logged
 */
void Gamelog::TestMode()
{
	const LoggedChangeMode *mode = nullptr;

	for (const LoggedAction &la : this->data->action) {
		for (const auto &lc : la.change) {
			if (lc->ct == GLCT_MODE) mode = static_cast<const LoggedChangeMode *>(lc.get());
		}
	}

	if (mode == nullptr || mode->mode != _game_mode || mode->landscape != _settings_game.game_creation.landscape) this->Mode();
}


/**
 * Logs triggered GRF bug.
 * @param grfid ID of problematic GRF
 * @param bug type of bug, @see enum GRFBugs
 * @param data additional data
 */
void Gamelog::GRFBug(uint32_t grfid, byte bug, uint64_t data)
{
	assert(this->action_type == GLAT_GRFBUG);

	this->Change(std::make_unique<LoggedChangeGRFBug>(data, grfid, bug));
}

/**
 * Logs GRF bug - rail vehicle has different length after reversing.
 * Ensures this is logged only once for each GRF and engine type
 * This check takes some time, but it is called pretty seldom, so it
 * doesn't matter that much (ideally it shouldn't be called at all).
 * @param grfid the broken NewGRF
 * @param internal_id the internal ID of whatever's broken in the NewGRF
 * @return true iff a unique record was done
 */
bool Gamelog::GRFBugReverse(uint32_t grfid, uint16_t internal_id)
{
	for (const LoggedAction &la : this->data->action) {
		for (const auto &lc : la.change) {
			if (lc->ct == GLCT_GRFBUG) {
				LoggedChangeGRFBug *bug = static_cast<LoggedChangeGRFBug *>(lc.get());
				if (bug->grfid == grfid && bug->bug == GBUG_VEH_LENGTH && bug->data == internal_id) {
					return false;
				}
			}
		}
	}

	this->StartAction(GLAT_GRFBUG);
	this->GRFBug(grfid, GBUG_VEH_LENGTH, internal_id);
	this->StopAction();

	return true;
}


/**
 * Decides if GRF should be logged
 * @param g grf to determine
 * @return true iff GRF is not static and is loaded
 */
static inline bool IsLoggableGrfConfig(const GRFConfig *g)
{
	return !HasBit(g->flags, GCF_STATIC) && g->status != GCS_NOT_FOUND;
}

/**
 * Logs removal of a GRF
 * @param grfid ID of removed GRF
 */
void Gamelog::GRFRemove(uint32_t grfid)
{
	assert(this->action_type == GLAT_LOAD || this->action_type == GLAT_GRF);

	this->Change(std::make_unique<LoggedChangeGRFRemoved>(grfid));
}

/**
 * Logs adding of a GRF
 * @param newg added GRF
 */
void Gamelog::GRFAdd(const GRFConfig *newg)
{
	assert(this->action_type == GLAT_LOAD || this->action_type == GLAT_START || this->action_type == GLAT_GRF);

	if (!IsLoggableGrfConfig(newg)) return;

	this->Change(std::make_unique<LoggedChangeGRFAdd>(newg->ident));
}

/**
 * Logs loading compatible GRF
 * (the same ID, but different MD5 hash)
 * @param newg new (updated) GRF
 */
void Gamelog::GRFCompatible(const GRFIdentifier *newg)
{
	assert(this->action_type == GLAT_LOAD || this->action_type == GLAT_GRF);

	this->Change(std::make_unique<LoggedChangeGRFChanged>(*newg));
}

/**
 * Logs changing GRF order
 * @param grfid GRF that is moved
 * @param offset how far it is moved, positive = moved down
 */
void Gamelog::GRFMove(uint32_t grfid, int32_t offset)
{
	assert(this->action_type == GLAT_GRF);

	this->Change(std::make_unique<LoggedChangeGRFMoved>(grfid, offset));
}

/**
 * Logs change in GRF parameters.
 * Details about parameters changed are not stored
 * @param grfid ID of GRF to store
 */
void Gamelog::GRFParameters(uint32_t grfid)
{
	assert(this->action_type == GLAT_GRF);

	this->Change(std::make_unique<LoggedChangeGRFParameterChanged>(grfid));
}

/**
 * Logs adding of list of GRFs.
 * Useful when old savegame is loaded or when new game is started
 * @param newg head of GRF linked list
 */
void Gamelog::GRFAddList(const GRFConfig *newg)
{
	assert(this->action_type == GLAT_START || this->action_type == GLAT_LOAD);

	for (; newg != nullptr; newg = newg->next) {
		this->GRFAdd(newg);
	}
}

/**
 * Generates GRFList
 * @param grfc head of GRF linked list
 */
static std::vector<const GRFConfig *> GenerateGRFList(const GRFConfig *grfc)
{
	std::vector<const GRFConfig *> list;
	for (const GRFConfig *g = grfc; g != nullptr; g = g->next) {
		if (IsLoggableGrfConfig(g)) list.push_back(g);
	}

	return list;
}

/**
 * Compares two NewGRF lists and logs any change
 * @param oldc original GRF list
 * @param newc new GRF list
 */
void Gamelog::GRFUpdate(const GRFConfig *oldc, const GRFConfig *newc)
{
	std::vector<const GRFConfig *> ol = GenerateGRFList(oldc);
	std::vector<const GRFConfig *> nl = GenerateGRFList(newc);

	uint o = 0, n = 0;

	while (o < ol.size() && n < nl.size()) {
		const GRFConfig *og = ol[o];
		const GRFConfig *ng = nl[n];

		if (og->ident.grfid != ng->ident.grfid) {
			uint oi, ni;
			for (oi = 0; oi < ol.size(); oi++) {
				if (ol[oi]->ident.grfid == nl[n]->ident.grfid) break;
			}
			if (oi < o) {
				/* GRF was moved, this change has been logged already */
				n++;
				continue;
			}
			if (oi == ol.size()) {
				/* GRF couldn't be found in the OLD list, GRF was ADDED */
				this->GRFAdd(nl[n++]);
				continue;
			}
			for (ni = 0; ni < nl.size(); ni++) {
				if (nl[ni]->ident.grfid == ol[o]->ident.grfid) break;
			}
			if (ni < n) {
				/* GRF was moved, this change has been logged already */
				o++;
				continue;
			}
			if (ni == nl.size()) {
				/* GRF couldn't be found in the NEW list, GRF was REMOVED */
				this->GRFRemove(ol[o++]->ident.grfid);
				continue;
			}

			/* o < oi < ol->n
			 * n < ni < nl->n */
			assert(ni > n && ni < nl.size());
			assert(oi > o && oi < ol.size());

			ni -= n; // number of GRFs it was moved downwards
			oi -= o; // number of GRFs it was moved upwards

			if (ni >= oi) { // prefer the one that is moved further
				/* GRF was moved down */
				this->GRFMove(ol[o++]->ident.grfid, ni);
			} else {
				this->GRFMove(nl[n++]->ident.grfid, -(int)oi);
			}
		} else {
			if (og->ident.md5sum != ng->ident.md5sum) {
				/* md5sum changed, probably loading 'compatible' GRF */
				this->GRFCompatible(&nl[n]->ident);
			}

			if (og->num_params != ng->num_params || og->param == ng->param) {
				this->GRFParameters(ol[o]->ident.grfid);
			}

			o++;
			n++;
		}
	}

	while (o < ol.size()) this->GRFRemove(ol[o++]->ident.grfid); // remaining GRFs were removed ...
	while (n < nl.size()) this->GRFAdd   (nl[n++]);              // ... or added
}

/**
 * Get some basic information from the given gamelog.
 * @param[out] last_ottd_rev OpenTTD NewGRF version from the binary that saved the savegame last.
 * @param[out] ever_modified Max value of 'modified' from all binaries that ever saved this savegame.
 * @param[out] removed_newgrfs Set to true if any NewGRFs have been removed.
 */
void Gamelog::Info(uint32_t *last_ottd_rev, byte *ever_modified, bool *removed_newgrfs)
{
	for (const LoggedAction &la : this->data->action) {
		for (const auto &lc : la.change) {
			switch (lc->ct) {
				default: break;

				case GLCT_REVISION: {
					const LoggedChangeRevision *rev = static_cast<const LoggedChangeRevision *>(lc.get());
					*last_ottd_rev = rev->newgrf;
					*ever_modified = std::max(*ever_modified, rev->modified);
					break;
				}

				case GLCT_GRFREM:
					*removed_newgrfs = true;
					break;
			}
		}
	}
}

/**
 * Try to find the overridden GRF identifier of the given GRF.
 * @param c the GRF to get the 'previous' version of.
 * @return the GRF identifier or \a c if none could be found.
 */
const GRFIdentifier *Gamelog::GetOverriddenIdentifier(const GRFConfig *c)
{
	assert(c != nullptr);
	const LoggedAction &la = this->data->action.back();
	if (la.at != GLAT_LOAD) return &c->ident;

	for (const auto &lc : la.change) {
		if (lc->ct != GLCT_GRFCOMPAT) continue;

		const LoggedChangeGRFChanged *grf = static_cast<const LoggedChangeGRFChanged *>(lc.get());
		if (grf->grfid == c->ident.grfid) return grf;
	}

	return &c->ident;
}