summaryrefslogtreecommitdiff
path: root/src/cargopacket.cpp
blob: 9b96be62eb671a15e480775eb90dd85bffcea0dc (plain)
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
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
/* $Id$ */

/*
 * 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 cargopacket.cpp Implementation of the cargo packets. */

#include "stdafx.h"
#include "station_base.h"
#include "core/pool_func.hpp"
#include "core/random_func.hpp"
#include "economy_base.h"
#include "cargoaction.h"
#include "order_type.h"

#include "safeguards.h"

/* Initialize the cargopacket-pool */
CargoPacketPool _cargopacket_pool("CargoPacket");
INSTANTIATE_POOL_METHODS(CargoPacket)

/**
 * Create a new packet for savegame loading.
 */
CargoPacket::CargoPacket()
{
	this->source_type = ST_INDUSTRY;
	this->source_id   = INVALID_SOURCE;
}

/**
 * Creates a new cargo packet.
 * @param source      Source station of the packet.
 * @param source_xy   Source location of the packet.
 * @param count       Number of cargo entities to put in this packet.
 * @param source_type 'Type' of source the packet comes from (for subsidies).
 * @param source_id   Actual source of the packet (for subsidies).
 * @pre count != 0
 * @note We have to zero memory ourselves here because we are using a 'new'
 * that, in contrary to all other pools, does not memset to 0.
 */
CargoPacket::CargoPacket(StationID source, TileIndex source_xy, uint16 count, SourceType source_type, SourceID source_id) :
	feeder_share(0),
	count(count),
	days_in_transit(0),
	source_id(source_id),
	source(source),
	source_xy(source_xy),
	loaded_at_xy(0)
{
	assert(count != 0);
	this->source_type  = source_type;
}

/**
 * Creates a new cargo packet. Initializes the fields that cannot be changed later.
 * Used when loading or splitting packets.
 * @param count           Number of cargo entities to put in this packet.
 * @param days_in_transit Number of days the cargo has been in transit.
 * @param source          Station the cargo was initially loaded.
 * @param source_xy       Station location the cargo was initially loaded.
 * @param loaded_at_xy    Location the cargo was loaded last.
 * @param feeder_share    Feeder share the packet has already accumulated.
 * @param source_type     'Type' of source the packet comes from (for subsidies).
 * @param source_id       Actual source of the packet (for subsidies).
 * @note We have to zero memory ourselves here because we are using a 'new'
 * that, in contrary to all other pools, does not memset to 0.
 */
CargoPacket::CargoPacket(uint16 count, byte days_in_transit, StationID source, TileIndex source_xy, TileIndex loaded_at_xy, Money feeder_share, SourceType source_type, SourceID source_id) :
		feeder_share(feeder_share),
		count(count),
		days_in_transit(days_in_transit),
		source_id(source_id),
		source(source),
		source_xy(source_xy),
		loaded_at_xy(loaded_at_xy)
{
	assert(count != 0);
	this->source_type = source_type;
}

/**
 * Split this packet in two and return the split off part.
 * @param new_size Size of the split part.
 * @return Split off part, or NULL if no packet could be allocated!
 */
CargoPacket *CargoPacket::Split(uint new_size)
{
	if (!CargoPacket::CanAllocateItem()) return NULL;

	Money fs = this->FeederShare(new_size);
	CargoPacket *cp_new = new CargoPacket(new_size, this->days_in_transit, this->source, this->source_xy, this->loaded_at_xy, fs, this->source_type, this->source_id);
	this->feeder_share -= fs;
	this->count -= new_size;
	return cp_new;
}

/**
 * Merge another packet into this one.
 * @param cp Packet to be merged in.
 */
void CargoPacket::Merge(CargoPacket *cp)
{
	this->count += cp->count;
	this->feeder_share += cp->feeder_share;
	delete cp;
}

/**
 * Reduce the packet by the given amount and remove the feeder share.
 * @param count Amount to be removed.
 */
void CargoPacket::Reduce(uint count)
{
	assert(count < this->count);
	this->feeder_share -= this->FeederShare(count);
	this->count -= count;
}

/**
 * Invalidates (sets source_id to INVALID_SOURCE) all cargo packets from given source.
 * @param src_type Type of source.
 * @param src Index of source.
 */
/* static */ void CargoPacket::InvalidateAllFrom(SourceType src_type, SourceID src)
{
	CargoPacket *cp;
	FOR_ALL_CARGOPACKETS(cp) {
		if (cp->source_type == src_type && cp->source_id == src) cp->source_id = INVALID_SOURCE;
	}
}

/**
 * Invalidates (sets source to INVALID_STATION) all cargo packets from given station.
 * @param sid Station that gets removed.
 */
/* static */ void CargoPacket::InvalidateAllFrom(StationID sid)
{
	CargoPacket *cp;
	FOR_ALL_CARGOPACKETS(cp) {
		if (cp->source == sid) cp->source = INVALID_STATION;
	}
}

/*
 *
 * Cargo list implementation
 *
 */

/**
 * Destroy the cargolist ("frees" all cargo packets).
 */
template <class Tinst, class Tcont>
CargoList<Tinst, Tcont>::~CargoList()
{
	for (Iterator it(this->packets.begin()); it != this->packets.end(); ++it) {
		delete *it;
	}
}

/**
 * Empty the cargo list, but don't free the cargo packets;
 * the cargo packets are cleaned by CargoPacket's CleanPool.
 */
template <class Tinst, class Tcont>
void CargoList<Tinst, Tcont>::OnCleanPool()
{
	this->packets.clear();
}

/**
 * Update the cached values to reflect the removal of this packet or part of it.
 * Decreases count and days_in_transit.
 * @param cp Packet to be removed from cache.
 * @param count Amount of cargo from the given packet to be removed.
 */
template <class Tinst, class Tcont>
void CargoList<Tinst, Tcont>::RemoveFromCache(const CargoPacket *cp, uint count)
{
	assert(count <= cp->count);
	this->count                 -= count;
	this->cargo_days_in_transit -= cp->days_in_transit * count;
}

/**
 * Update the cache to reflect adding of this packet.
 * Increases count and days_in_transit.
 * @param cp New packet to be inserted.
 */
template <class Tinst, class Tcont>
void CargoList<Tinst, Tcont>::AddToCache(const CargoPacket *cp)
{
	this->count                 += cp->count;
	this->cargo_days_in_transit += cp->days_in_transit * cp->count;
}

/** Invalidates the cached data and rebuilds it. */
template <class Tinst, class Tcont>
void CargoList<Tinst, Tcont>::InvalidateCache()
{
	this->count = 0;
	this->cargo_days_in_transit = 0;

	for (ConstIterator it(this->packets.begin()); it != this->packets.end(); it++) {
		static_cast<Tinst *>(this)->AddToCache(*it);
	}
}

/**
 * Tries to merge the second packet into the first and return if that was
 * successful.
 * @param icp Packet to be merged into.
 * @param cp Packet to be eliminated.
 * @return If the packets could be merged.
 */
template <class Tinst, class Tcont>
/* static */ bool CargoList<Tinst, Tcont>::TryMerge(CargoPacket *icp, CargoPacket *cp)
{
	if (Tinst::AreMergable(icp, cp) &&
			icp->count + cp->count <= CargoPacket::MAX_COUNT) {
		icp->Merge(cp);
		return true;
	} else {
		return false;
	}
}

/*
 *
 * Vehicle cargo list implementation.
 *
 */

/**
 * Appends the given cargo packet. Tries to merge it with another one in the
 * packets list. If no fitting packet is found, appends it. You can only append
 * packets to the ranges of packets designated for keeping or loading.
 * Furthermore if there are already packets reserved for loading you cannot
 * directly add packets to the "keep" list. You first have to load the reserved
 * ones.
 * @warning After appending this packet may not exist anymore!
 * @note Do not use the cargo packet anymore after it has been appended to this CargoList!
 * @param cp Cargo packet to add.
 * @param action Either MTA_KEEP if you want to add the packet directly or MTA_LOAD
 * if you want to reserve it first.
 * @pre cp != NULL
 * @pre action == MTA_LOAD || (action == MTA_KEEP && this->designation_counts[MTA_LOAD] == 0)
 */
void VehicleCargoList::Append(CargoPacket *cp, MoveToAction action)
{
	assert(cp != NULL);
	assert(action == MTA_LOAD ||
			(action == MTA_KEEP && this->action_counts[MTA_LOAD] == 0));
	this->AddToMeta(cp, action);

	if (this->count == cp->count) {
		this->packets.push_back(cp);
		return;
	}

	uint sum = cp->count;
	for (ReverseIterator it(this->packets.rbegin()); it != this->packets.rend(); it++) {
		CargoPacket *icp = *it;
		if (VehicleCargoList::TryMerge(icp, cp)) return;
		sum += icp->count;
		if (sum >= this->action_counts[action]) {
			this->packets.push_back(cp);
			return;
		}
	}

	NOT_REACHED();
}

/**
 * Shifts cargo from the front of the packet list and applies some action to it.
 * @tparam Taction Action class or function to be used. It should define
 *                 "bool operator()(CargoPacket *)". If true is returned the
 *                 cargo packet will be removed from the list. Otherwise it
 *                 will be kept and the loop will be aborted.
 * @param action Action instance to be applied.
 */
template<class Taction>
void VehicleCargoList::ShiftCargo(Taction action)
{
	Iterator it(this->packets.begin());
	while (it != this->packets.end() && action.MaxMove() > 0) {
		CargoPacket *cp = *it;
		if (action(cp)) {
			it = this->packets.erase(it);
		} else {
			break;
		}
	}
}

/**
 * Pops cargo from the back of the packet list and applies some action to it.
 * @tparam Taction Action class or function to be used. It should define
 *                 "bool operator()(CargoPacket *)". If true is returned the
 *                 cargo packet will be removed from the list. Otherwise it
 *                 will be kept and the loop will be aborted.
 * @param action Action instance to be applied.
 */
template<class Taction>
void VehicleCargoList::PopCargo(Taction action)
{
	if (this->packets.empty()) return;
	Iterator it(--(this->packets.end()));
	Iterator begin(this->packets.begin());
	while (action.MaxMove() > 0) {
		CargoPacket *cp = *it;
		if (action(cp)) {
			if (it != begin) {
				this->packets.erase(it--);
			} else {
				this->packets.erase(it);
				break;
			}
		} else {
			break;
		}
	}
}

/**
 * Update the cached values to reflect the removal of this packet or part of it.
 * Decreases count, feeder share and days_in_transit.
 * @param cp Packet to be removed from cache.
 * @param count Amount of cargo from the given packet to be removed.
 */
void VehicleCargoList::RemoveFromCache(const CargoPacket *cp, uint count)
{
	this->feeder_share -= cp->FeederShare(count);
	this->Parent::RemoveFromCache(cp, count);
}

/**
 * Update the cache to reflect adding of this packet.
 * Increases count, feeder share and days_in_transit.
 * @param cp New packet to be inserted.
 */
void VehicleCargoList::AddToCache(const CargoPacket *cp)
{
	this->feeder_share += cp->feeder_share;
	this->Parent::AddToCache(cp);
}

/**
 * Removes a packet or part of it from the metadata.
 * @param cp Packet to be removed.
 * @param action MoveToAction of the packet (for updating the counts).
 * @param count Amount of cargo to be removed.
 */
void VehicleCargoList::RemoveFromMeta(const CargoPacket *cp, MoveToAction action, uint count)
{
	assert(count <= this->action_counts[action]);
	this->AssertCountConsistency();
	this->RemoveFromCache(cp, count);
	this->action_counts[action] -= count;
	this->AssertCountConsistency();
}

/**
 * Adds a packet to the metadata.
 * @param cp Packet to be added.
 * @param action MoveToAction of the packet.
 */
void VehicleCargoList::AddToMeta(const CargoPacket *cp, MoveToAction action)
{
	this->AssertCountConsistency();
	this->AddToCache(cp);
	this->action_counts[action] += cp->count;
	this->AssertCountConsistency();
}

/**
 * Ages the all cargo in this list.
 */
void VehicleCargoList::AgeCargo()
{
	for (ConstIterator it(this->packets.begin()); it != this->packets.end(); it++) {
		CargoPacket *cp = *it;
		/* If we're at the maximum, then we can't increase no more. */
		if (cp->days_in_transit == 0xFF) continue;

		cp->days_in_transit++;
		this->cargo_days_in_transit += cp->count;
	}
}

/**
 * Sets loaded_at_xy to the current station for all cargo to be transfered.
 * This is done when stopping or skipping while the vehicle is unloading. In
 * that case the vehicle will get part of its transfer credits early and it may
 * get more transfer credits than it's entitled to.
 * @param xy New loaded_at_xy for the cargo.
 */
void VehicleCargoList::SetTransferLoadPlace(TileIndex xy)
{
	uint sum = 0;
	for (Iterator it = this->packets.begin(); sum < this->action_counts[MTA_TRANSFER]; ++it) {
		CargoPacket *cp = *it;
		cp->loaded_at_xy = xy;
		sum += cp->count;
	}
}

/**
 * Choose action to be performed with the given cargo packet.
 * @param cp The packet.
 * @param cargo_next Next hop the cargo wants to pass.
 * @param current_station Current station of the vehicle carrying the cargo.
 * @param accepted If the cargo is accepted at the current station.
 * @param next_station Next station(s) the vehicle may stop at.
 * @return MoveToAction to be performed.
 */
/* static */ VehicleCargoList::MoveToAction VehicleCargoList::ChooseAction(const CargoPacket *cp, StationID cargo_next,
		StationID current_station, bool accepted, StationIDStack next_station)
{
	if (cargo_next == INVALID_STATION) {
		return (accepted && cp->source != current_station) ? MTA_DELIVER : MTA_KEEP;
	} else if (cargo_next == current_station) {
		return MTA_DELIVER;
	} else if (next_station.Contains(cargo_next)) {
		return MTA_KEEP;
	} else {
		return MTA_TRANSFER;
	}
}

/**
 * Stages cargo for unloading. The cargo is sorted so that packets to be
 * transferred, delivered or kept are in consecutive chunks in the list. At the
 * same time the designation_counts are updated to reflect the size of those
 * chunks.
 * @param accepted If the cargo will be accepted at the station.
 * @param current_station ID of the station.
 * @param next_station ID of the station the vehicle will go to next.
 * @param order_flags OrderUnloadFlags that will apply to the unload operation.
 * @param ge GoodsEntry for getting the flows.
 * @param payment Payment object for registering transfers.
 * return If any cargo will be unloaded.
 */
bool VehicleCargoList::Stage(bool accepted, StationID current_station, StationIDStack next_station, uint8 order_flags, const GoodsEntry *ge, CargoPayment *payment)
{
	this->AssertCountConsistency();
	assert(this->action_counts[MTA_LOAD] == 0);
	this->action_counts[MTA_TRANSFER] = this->action_counts[MTA_DELIVER] = this->action_counts[MTA_KEEP] = 0;
	Iterator deliver = this->packets.end();
	Iterator it = this->packets.begin();
	uint sum = 0;

	bool force_keep = (order_flags & OUFB_NO_UNLOAD) != 0;
	bool force_unload = (order_flags & OUFB_UNLOAD) != 0;
	bool force_transfer = (order_flags & (OUFB_TRANSFER | OUFB_UNLOAD)) != 0;
	assert(this->count > 0 || it == this->packets.end());
	while (sum < this->count) {
		CargoPacket *cp = *it;

		this->packets.erase(it++);
		StationID cargo_next = INVALID_STATION;
		MoveToAction action = MTA_LOAD;
		if (force_keep) {
			action = MTA_KEEP;
		} else if (force_unload && accepted && cp->source != current_station) {
			action = MTA_DELIVER;
		} else if (force_transfer) {
			action = MTA_TRANSFER;
			/* We cannot send the cargo to any of the possible next hops and
			 * also not to the current station. */
			FlowStatMap::const_iterator flow_it(ge->flows.find(cp->source));
			if (flow_it == ge->flows.end()) {
				cargo_next = INVALID_STATION;
			} else {
				FlowStat new_shares = flow_it->second;
				new_shares.ChangeShare(current_station, INT_MIN);
				StationIDStack excluded = next_station;
				while (!excluded.IsEmpty() && !new_shares.GetShares()->empty()) {
					new_shares.ChangeShare(excluded.Pop(), INT_MIN);
				}
				if (new_shares.GetShares()->empty()) {
					cargo_next = INVALID_STATION;
				} else {
					cargo_next = new_shares.GetVia();
				}
			}
		} else {
			/* Rewrite an invalid source station to some random other one to
			 * avoid keeping the cargo in the vehicle forever. */
			if (cp->source == INVALID_STATION && !ge->flows.empty()) {
				cp->source = ge->flows.begin()->first;
			}
			bool restricted = false;
			FlowStatMap::const_iterator flow_it(ge->flows.find(cp->source));
			if (flow_it == ge->flows.end()) {
				cargo_next = INVALID_STATION;
			} else {
				cargo_next = flow_it->second.GetViaWithRestricted(restricted);
			}
			action = VehicleCargoList::ChooseAction(cp, cargo_next, current_station, accepted, next_station);
			if (restricted && action == MTA_TRANSFER) {
				/* If the flow is restricted we can't transfer to it. Choose an
				 * unrestricted one instead. */
				cargo_next = flow_it->second.GetVia();
				action = VehicleCargoList::ChooseAction(cp, cargo_next, current_station, accepted, next_station);
			}
		}
		Money share;
		switch (action) {
			case MTA_KEEP:
				this->packets.push_back(cp);
				if (deliver == this->packets.end()) --deliver;
				break;
			case MTA_DELIVER:
				this->packets.insert(deliver, cp);
				break;
			case MTA_TRANSFER:
				this->packets.push_front(cp);
				/* Add feeder share here to allow reusing field for next station. */
				share = payment->PayTransfer(cp, cp->count);
				cp->AddFeederShare(share);
				this->feeder_share += share;
				cp->next_station = cargo_next;
				break;
			default:
				NOT_REACHED();
		}
		this->action_counts[action] += cp->count;
		sum += cp->count;
	}
	this->AssertCountConsistency();
	return this->action_counts[MTA_DELIVER] > 0 || this->action_counts[MTA_TRANSFER] > 0;
}

/** Invalidates the cached data and rebuild it. */
void VehicleCargoList::InvalidateCache()
{
	this->feeder_share = 0;
	this->Parent::InvalidateCache();
}

/**
 * Moves some cargo from one designation to another. You can only move
 * between adjacent designations. E.g. you can keep cargo that was previously
 * reserved (MTA_LOAD), but you can't reserve cargo that's marked as to be
 * delivered. Furthermore, as this method doesn't change the actual packets,
 * you cannot move cargo from or to MTA_TRANSFER. You need a specialized
 * template method for that.
 * @tparam from Previous designation of cargo.
 * @tparam to New designation of cargo.
 * @param max_move Maximum amount of cargo to reassign.
 * @return Amount of cargo actually reassigned.
 */
template<VehicleCargoList::MoveToAction Tfrom, VehicleCargoList::MoveToAction Tto>
uint VehicleCargoList::Reassign(uint max_move, TileOrStationID)
{
	assert_tcompile(Tfrom != MTA_TRANSFER && Tto != MTA_TRANSFER);
	assert_tcompile(Tfrom - Tto == 1 || Tto - Tfrom == 1);
	max_move = min(this->action_counts[Tfrom], max_move);
	this->action_counts[Tfrom] -= max_move;
	this->action_counts[Tto] += max_move;
	return max_move;
}

/**
 * Reassign cargo from MTA_DELIVER to MTA_TRANSFER and take care of the next
 * station the cargo wants to visit.
 * @param max_move Maximum amount of cargo to reassign.
 * @param next_station Station to record as next hop in the reassigned packets.
 * @return Amount of cargo actually reassigned.
 */
template<>
uint VehicleCargoList::Reassign<VehicleCargoList::MTA_DELIVER, VehicleCargoList::MTA_TRANSFER>(uint max_move, TileOrStationID next_station)
{
	max_move = min(this->action_counts[MTA_DELIVER], max_move);

	uint sum = 0;
	for (Iterator it(this->packets.begin()); sum < this->action_counts[MTA_TRANSFER] + max_move;) {
		CargoPacket *cp = *it++;
		sum += cp->Count();
		if (sum <= this->action_counts[MTA_TRANSFER]) continue;
		if (sum > this->action_counts[MTA_TRANSFER] + max_move) {
			CargoPacket *cp_split = cp->Split(sum - this->action_counts[MTA_TRANSFER] + max_move);
			sum -= cp_split->Count();
			this->packets.insert(it, cp_split);
		}
		cp->next_station = next_station;
	}

	this->action_counts[MTA_DELIVER] -= max_move;
	this->action_counts[MTA_TRANSFER] += max_move;
	return max_move;
}

/**
 * Returns reserved cargo to the station and removes it from the cache.
 * @param max_move Maximum amount of cargo to move.
 * @param dest Station the cargo is returned to.
 * @param ID of next the station the cargo wants to go next.
 * @return Amount of cargo actually returned.
 */
uint VehicleCargoList::Return(uint max_move, StationCargoList *dest, StationID next)
{
	max_move = min(this->action_counts[MTA_LOAD], max_move);
	this->PopCargo(CargoReturn(this, dest, max_move, next));
	return max_move;
}

/**
 * Shifts cargo between two vehicles.
 * @param dest Other vehicle's cargo list.
 * @param max_move Maximum amount of cargo to be moved.
 * @return Amount of cargo actually moved.
 */
uint VehicleCargoList::Shift(uint max_move, VehicleCargoList *dest)
{
	max_move = min(this->count, max_move);
	this->PopCargo(CargoShift(this, dest, max_move));
	return max_move;
}

/**
 * Unloads cargo at the given station. Deliver or transfer, depending on the
 * ranges defined by designation_counts.
 * @param dest StationCargoList to add transferred cargo to.
 * @param max_move Maximum amount of cargo to move.
 * @param payment Payment object to register payments in.
 * @return Amount of cargo actually unloaded.
 */
uint VehicleCargoList::Unload(uint max_move, StationCargoList *dest, CargoPayment *payment)
{
	uint moved = 0;
	if (this->action_counts[MTA_TRANSFER] > 0) {
		uint move = min(this->action_counts[MTA_TRANSFER], max_move);
		this->ShiftCargo(CargoTransfer(this, dest, move));
		moved += move;
	}
	if (this->action_counts[MTA_TRANSFER] == 0 && this->action_counts[MTA_DELIVER] > 0 && moved < max_move) {
		uint move = min(this->action_counts[MTA_DELIVER], max_move - moved);
		this->ShiftCargo(CargoDelivery(this, move, payment));
		moved += move;
	}
	return moved;
}

/**
 * Truncates the cargo in this list to the given amount. It leaves the
 * first cargo entities and removes max_move from the back of the list.
 * @param max_move Maximum amount of entities to be removed from the list.
 * @return Amount of entities actually moved.
 */
uint VehicleCargoList::Truncate(uint max_move)
{
	max_move = min(this->count, max_move);
	this->PopCargo(CargoRemoval<VehicleCargoList>(this, max_move));
	return max_move;
}

/**
 * Routes packets with station "avoid" as next hop to a different place.
 * @param max_move Maximum amount of cargo to move.
 * @param dest List to prepend the cargo to.
 * @param avoid Station to exclude from routing and current next hop of packets to reroute.
 * @param avoid2 Additional station to exclude from routing.
 * @oaram ge GoodsEntry to get the routing info from.
 */
uint VehicleCargoList::Reroute(uint max_move, VehicleCargoList *dest, StationID avoid, StationID avoid2, const GoodsEntry *ge)
{
	max_move = min(this->action_counts[MTA_TRANSFER], max_move);
	this->ShiftCargo(VehicleCargoReroute(this, dest, max_move, avoid, avoid2, ge));
	return max_move;
}

/*
 *
 * Station cargo list implementation.
 *
 */

/**
 * Appends the given cargo packet to the range of packets with the same next station
 * @warning After appending this packet may not exist anymore!
 * @note Do not use the cargo packet anymore after it has been appended to this CargoList!
 * @param next the next hop
 * @param cp the cargo packet to add
 * @pre cp != NULL
 */
void StationCargoList::Append(CargoPacket *cp, StationID next)
{
	assert(cp != NULL);
	this->AddToCache(cp);

	StationCargoPacketMap::List &list = this->packets[next];
	for (StationCargoPacketMap::List::reverse_iterator it(list.rbegin());
			it != list.rend(); it++) {
		if (StationCargoList::TryMerge(*it, cp)) return;
	}

	/* The packet could not be merged with another one */
	list.push_back(cp);
}

/**
 * Shifts cargo from the front of the packet list for a specific station and
 * applies some action to it.
 * @tparam Taction Action class or function to be used. It should define
 *                 "bool operator()(CargoPacket *)". If true is returned the
 *                 cargo packet will be removed from the list. Otherwise it
 *                 will be kept and the loop will be aborted.
 * @param action Action instance to be applied.
 * @param next Next hop the cargo wants to visit.
 * @return True if all packets with the given next hop have been removed,
 *         False otherwise.
 */
template <class Taction>
bool StationCargoList::ShiftCargo(Taction &action, StationID next)
{
	std::pair<Iterator, Iterator> range(this->packets.equal_range(next));
	for (Iterator it(range.first); it != range.second && it.GetKey() == next;) {
		if (action.MaxMove() == 0) return false;
		CargoPacket *cp = *it;
		if (action(cp)) {
			it = this->packets.erase(it);
		} else {
			return false;
		}
	}
	return true;
}

/**
 * Shifts cargo from the front of the packet list for a specific station and
 * and optional also from the list for "any station", then applies some action
 * to it.
 * @tparam Taction Action class or function to be used. It should define
 *                 "bool operator()(CargoPacket *)". If true is returned the
 *                 cargo packet will be removed from the list. Otherwise it
 *                 will be kept and the loop will be aborted.
 * @param action Action instance to be applied.
 * @param next Next hop the cargo wants to visit.
 * @param include_invalid If cargo from the INVALID_STATION list should be
 *                        used if necessary.
 * @return Amount of cargo actually moved.
 */
template <class Taction>
uint StationCargoList::ShiftCargo(Taction action, StationIDStack next, bool include_invalid)
{
	uint max_move = action.MaxMove();
	while (!next.IsEmpty()) {
		this->ShiftCargo(action, next.Pop());
		if (action.MaxMove() == 0) break;
	}
	if (include_invalid && action.MaxMove() > 0) {
		this->ShiftCargo(action, INVALID_STATION);
	}
	return max_move - action.MaxMove();
}

/**
 * Truncates where each destination loses roughly the same percentage of its
 * cargo. This is done by randomizing the selection of packets to be removed.
 * Optionally count the cargo by origin station.
 * @param max_move Maximum amount of cargo to remove.
 * @param cargo_per_source Container for counting the cargo by origin.
 * @return Amount of cargo actually moved.
 */
uint StationCargoList::Truncate(uint max_move, StationCargoAmountMap *cargo_per_source)
{
	max_move = min(max_move, this->count);
	uint prev_count = this->count;
	uint moved = 0;
	uint loop = 0;
	bool do_count = cargo_per_source != NULL;
	while (max_move > moved) {
		for (Iterator it(this->packets.begin()); it != this->packets.end();) {
			CargoPacket *cp = *it;
			if (prev_count > max_move && RandomRange(prev_count) < prev_count - max_move) {
				if (do_count && loop == 0) {
					(*cargo_per_source)[cp->source] += cp->count;
				}
				++it;
				continue;
			}
			uint diff = max_move - moved;
			if (cp->count > diff) {
				if (diff > 0) {
					this->RemoveFromCache(cp, diff);
					cp->Reduce(diff);
					moved += diff;
				}
				if (loop > 0) {
					if (do_count) (*cargo_per_source)[cp->source] -= diff;
					return moved;
				} else {
					if (do_count) (*cargo_per_source)[cp->source] += cp->count;
					++it;
				}
			} else {
				it = this->packets.erase(it);
				if (do_count && loop > 0) {
					(*cargo_per_source)[cp->source] -= cp->count;
				}
				moved += cp->count;
				this->RemoveFromCache(cp, cp->count);
				delete cp;
			}
		}
		loop++;
	}
	return moved;
}

/**
 * Reserves cargo for loading onto the vehicle.
 * @param max_move Maximum amount of cargo to reserve.
 * @param dest VehicleCargoList to reserve for.
 * @param load_place Tile index of the current station.
 * @param next_station Next station(s) the loading vehicle will visit.
 * @return Amount of cargo actually reserved.
 */
uint StationCargoList::Reserve(uint max_move, VehicleCargoList *dest, TileIndex load_place, StationIDStack next_station)
{
	return this->ShiftCargo(CargoReservation(this, dest, max_move, load_place), next_station, true);
}

/**
 * Loads cargo onto a vehicle. If the vehicle has reserved cargo load that.
 * Otherwise load cargo from the station.
 * @param max_move Amount of cargo to load.
 * @param dest Vehicle cargo list where the cargo resides.
 * @param load_place The new loaded_at_xy to be assigned to packets being moved.
 * @param next_station Next station(s) the loading vehicle will visit.
 * @return Amount of cargo actually loaded.
 * @note Vehicles may or may not reserve, depending on their orders. The two
 *       modes of loading are exclusive, though. If cargo is reserved we don't
 *       need to load unreserved cargo.
 */
uint StationCargoList::Load(uint max_move, VehicleCargoList *dest, TileIndex load_place, StationIDStack next_station)
{
	uint move = min(dest->ActionCount(VehicleCargoList::MTA_LOAD), max_move);
	if (move > 0) {
		this->reserved_count -= move;
		dest->Reassign<VehicleCargoList::MTA_LOAD, VehicleCargoList::MTA_KEEP>(move);
		return move;
	} else {
		return this->ShiftCargo(CargoLoad(this, dest, max_move, load_place), next_station, true);
	}
}

/**
 * Routes packets with station "avoid" as next hop to a different place.
 * @param max_move Maximum amount of cargo to move.
 * @param dest List to append the cargo to.
 * @param avoid Station to exclude from routing and current next hop of packets to reroute.
 * @param avoid2 Additional station to exclude from routing.
 * @oaram ge GoodsEntry to get the routing info from.
 */
uint StationCargoList::Reroute(uint max_move, StationCargoList *dest, StationID avoid, StationID avoid2, const GoodsEntry *ge)
{
	return this->ShiftCargo(StationCargoReroute(this, dest, max_move, avoid, avoid2, ge), avoid, false);
}

/*
 * We have to instantiate everything we want to be usable.
 */
template class CargoList<VehicleCargoList, CargoPacketList>;
template class CargoList<StationCargoList, StationCargoPacketMap>;
template uint VehicleCargoList::Reassign<VehicleCargoList::MTA_DELIVER, VehicleCargoList::MTA_KEEP>(uint, TileOrStationID);