riichienv-core 0.4.5

Japanese Mahjong (Riichi) game engine with MJAI protocol support
Documentation
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
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
#[cfg(test)]
mod unit_tests {
    use crate::action::Phase;
    use crate::agari::{is_agari, is_chiitoitsu, is_kokushi};
    use crate::score::calculate_score;
    use crate::types::Hand;

    #[test]
    fn test_agari_standard() {
        // Pinfu Tsumo: 123 456 789 m 234 p 55 s
        let tiles = [
            0, 1, 2, // 123m
            3, 4, 5, // 456m
            6, 7, 8, // 789m
            9, 10, 11, // 123p (mapped to 9,10,11)
            18, 18, // 1s pair (mapped to 18)
        ];
        let mut hand = Hand::new(Some(tiles.to_vec()));
        assert!(is_agari(&mut hand), "Should be agari");
    }

    #[test]
    fn test_basic_pinfu() {
        // 123m 456m 789m 123p 11s
        // m: 0-8, p: 9-17, s: 18-26_
        // 123p -> 9, 10, 11
        // 11s -> 18, 18
        let mut hand = Hand::new(None);
        // 123m
        hand.add(0);
        hand.add(1);
        hand.add(2);
        // 456m
        hand.add(3);
        hand.add(4);
        hand.add(5);
        // 789m
        hand.add(6);
        hand.add(7);
        hand.add(8);
        // 123p
        hand.add(9);
        hand.add(10);
        hand.add(11);
        // 11s (pair)
        hand.add(18);
        hand.add(18);

        assert!(is_agari(&mut hand));
    }

    #[test]
    fn test_chiitoitsu() {
        let mut hand = Hand::new(None);
        let pairs = [0, 2, 4, 6, 8, 10, 12];
        for &t in &pairs {
            hand.add(t);
            hand.add(t);
        }
        assert!(is_chiitoitsu(&hand));
        assert!(is_agari(&mut hand));
    }

    #[test]
    fn test_kokushi() {
        let mut hand = Hand::new(None);
        // 1m,9m, 1p,9p, 1s,9s, 1z-7z
        let terminals = [0, 8, 9, 17, 18, 26, 27, 28, 29, 30, 31, 32, 33];
        for &t in &terminals {
            hand.add(t);
        }
        hand.add(0); // Double 1m
        assert!(is_kokushi(&hand));
        assert!(is_agari(&mut hand));
    }

    #[test]
    fn test_score_calculation() {
        // Current implementation does NOT do Kiriage Mangan (rounding 1920->2000).
        // So base is 1920.
        // Oya pays: ceil(1920*2/100)*100 = 3900.
        // Ko pays: ceil(1920/100)*100 = 2000.
        // Total: 3900 + 2000*2 = 7900.

        let score = calculate_score(4, 30, false, true, 0, 4); // Ko Tsumo

        assert_eq!(score.pay_tsumo_oya, 3900);
        assert_eq!(score.pay_tsumo_ko, 2000);
        assert_eq!(score.total, 7900); // 3900 + 2000 + 2000
    }

    #[test]
    fn test_tsuu_iisou() {
        use crate::yaku::{YakuContext, calculate_yaku};
        let mut hand = Hand::new(None);
        // 111z, 222z, 333z, 444z, 55z
        for &t in &[27, 28, 29, 30] {
            hand.add(t);
            hand.add(t);
            hand.add(t);
        }
        hand.add(31);
        hand.add(31);

        let res = calculate_yaku(&hand, &[], &YakuContext::default(), 31);
        assert!(res.han >= 13);
        assert!(res.yaku_ids.contains(&39));
    }

    #[test]
    fn test_ryuu_iisou() {
        use crate::yaku::{YakuContext, calculate_yaku};
        let mut hand = Hand::new(None);
        // 234s, 666s, 888s, 6s6s6s (Wait, 6s6s6s is already there)
        // Correct 234s, 666s, 888s, Hatsuz, 6s6s (pair)
        let tiles = [
            19, 20, 21, // 234s
            23, 23, 23, // 666s
            25, 25, 25, // 888s
            32, 32, 32, // Hatsuz
            19, 19, // 2s pair
        ];
        for &t in &tiles {
            hand.add(t);
        }

        let res = calculate_yaku(&hand, &[], &YakuContext::default(), 19);
        assert!(res.han >= 13);
        assert!(res.yaku_ids.contains(&40));
    }

    #[test]
    fn test_daisushii() {
        use crate::yaku::{YakuContext, calculate_yaku};
        let mut hand = Hand::new(None);
        // EEEz, SSSz, WWWz, NNNz, 11m
        for &t in &[27, 28, 29, 30] {
            hand.add(t);
            hand.add(t);
            hand.add(t);
        }
        hand.add(0);
        hand.add(0);

        let res = calculate_yaku(&hand, &[], &YakuContext::default(), 0);
        assert!(res.han >= 26);
        assert!(res.yaku_ids.contains(&50));
    }

    fn create_test_state(game_type: u8) -> crate::state::GameState {
        crate::state::GameState::new(game_type, false, None, 0, crate::rule::GameRule::default())
    }

    #[test]
    fn test_seeded_shuffle_changes_between_rounds() {
        let mut state = create_test_state(2);
        state.seed = Some(42);

        state._initialize_next_round(true, false);
        let digest1 = state.wall.wall_digest.clone();

        state._initialize_next_round(true, false);
        let digest2 = state.wall.wall_digest.clone();

        assert_ne!(
            digest1, digest2,
            "Wall digest should differ between rounds when seed is fixed"
        );
    }

    #[test]
    fn test_sudden_death_hanchan_logic() {
        use serde_json::Value;

        let mut state = create_test_state(2);
        state.round_wind = 1;
        state.kyoku_idx = 3;
        state.oya = 3;
        for i in 0..4 {
            state.players[i].score = 25000;
            state.players[i].nagashi_eligible = false;
        }
        state.needs_initialize_next_round = false;

        state._trigger_ryukyoku("exhaustive_draw");

        if state.needs_initialize_next_round {
            state._initialize_next_round(state.pending_oya_won, state.pending_is_draw);
            state.needs_initialize_next_round = false;
        }

        assert!(
            !state.is_done,
            "Game should not be done (Sudden Death should trigger)"
        );
        assert_eq!(state.round_wind, 2, "Should enter West round");
        assert_eq!(state.kyoku_idx, 0, "Should be West 1 (Kyoku 0)");
        assert_eq!(state.oya, 0, "Oya should rotate to player 0");

        let new_scores = [31000, 25000, 24000, 20000];
        for (player, &score) in state.players.iter_mut().zip(new_scores.iter()) {
            player.score = score;
        }

        state._trigger_ryukyoku("exhaustive_draw");
        if state.needs_initialize_next_round {
            state._initialize_next_round(state.pending_oya_won, state.pending_is_draw);
            state.needs_initialize_next_round = false;
        }

        assert!(
            state.is_done,
            "Game should be done (Score >= 30000 in West)"
        );

        let logs = &state.mjai_log;
        let event_types: Vec<String> = logs
            .iter()
            .filter_map(|s| {
                let v: Value = serde_json::from_str(s).ok()?;
                v.get("type")
                    .and_then(|t| t.as_str())
                    .map(|t| t.to_string())
            })
            .collect();

        let last_event = event_types.last().expect("Should have events");
        assert_eq!(last_event, "end_game");

        assert!(event_types.contains(&"ryukyoku".to_string()));
    }

    #[test]
    fn test_ryukyoku_deltas_are_reset_each_round_4p() {
        use serde_json::Value;

        let mut state = create_test_state(2);

        state.players[0].score_delta = 2300;
        state.players[1].score_delta = -2300;
        state.players[2].score_delta = 0;
        state.players[3].score_delta = 0;

        state._initialize_round(0, 0, 0, 0, None, None);
        state._trigger_ryukyoku("sufuurenta");

        let v: Value = state
            .mjai_log
            .iter()
            .rev()
            .find_map(|s| {
                let ev: Value = serde_json::from_str(s).ok()?;
                (ev["type"] == "ryukyoku").then_some(ev)
            })
            .expect("ryukyoku event should be logged");
        assert_eq!(v["reason"], "sufuurenta");

        let deltas: Vec<i32> = serde_json::from_value(v["deltas"].clone()).expect("deltas");
        assert_eq!(deltas, vec![0, 0, 0, 0]);
    }

    #[test]
    fn test_is_tenpai() {
        use crate::hand_evaluator::HandEvaluator;
        // 111,222,333m, 444p, 11s (Tenpai on 1s)
        let hand = vec![0, 1, 2, 4, 5, 6, 8, 9, 10, 12, 13, 14, 72];
        let calc = HandEvaluator::new(hand, Vec::new());
        assert!(calc.is_tenpai());
        let waits = calc.get_waits_u8();
        assert!(waits.contains(&18)); // 1s
    }

    #[test]
    fn test_kuikae_deadlock_repro() {
        use crate::action::{Action, ActionType};
        use std::collections::HashMap;

        let mut state = create_test_state(2);
        let pid = 0;

        // Hand: 4m, 5m, 6m, 6m. (12, 16, 20, 21)
        // 3m is 8.
        state.players[pid as usize].hand = vec![12, 16, 20, 21];

        // Setup P3 (Kamicha of P0)
        state.current_player = 3;
        state.phase = Phase::WaitAct;
        state.active_players = vec![3];
        state.players[3].hand.push(8); // Give 3m

        // Action: P3 discards 3m
        let mut actions = HashMap::new();
        actions.insert(3, Action::new(ActionType::Discard, Some(8), vec![], None));

        state.step(&actions);

        state.step(&actions);

        assert_eq!(
            state.phase,
            Phase::WaitAct,
            "Should proceed to WaitAct as deadlock Chi is filtered out"
        );
        assert_eq!(state.current_player, 0, "Should be P0's turn");

        // Verify current_claims is empty or does not contain 0
        if let Some(claims) = state.current_claims.get(&0) {
            assert!(claims.is_empty(), "P0 should have no legal claims");
        }
    }
    #[test]
    fn test_match_84_agari_check() {
        use crate::hand_evaluator::HandEvaluator;
        use crate::types::{Conditions, Wind};

        // Hand: 111m, 78p, 11123s, 789s
        // 1m: 0
        // 7p: 15. 8p: 16.
        // 1s: 18. 2s: 19. 3s: 20.
        // 7s: 24. 8s: 25. 9s: 26.

        let mut tiles = vec![
            0, 1, 2,  // 1m x3
            60, // 7p (15*4)
            64, // 8p (16*4)
            72, 73, 74,  // 1s x3
            76,  // 2s (19*4)
            80,  // 3s (20*4)
            96,  // 7s (24*4)
            100, // 8s (25*4)
            104, // 9s (26*4)
        ];
        tiles.sort();

        let calc = HandEvaluator::new(tiles, Vec::new());

        let cond = Conditions {
            tsumo: false,
            riichi: false,
            double_riichi: false,
            ippatsu: false,
            haitei: false,
            houtei: false,
            rinshan: false,
            chankan: false,
            tsumo_first_turn: false,
            player_wind: Wind::West,
            round_wind: Wind::East,
            riichi_sticks: 0,
            honba: 0,
            ..Default::default()
        };

        // 1. Check 6p (14 -> 56)
        let res6p = calc.calc(56, vec![], vec![], Some(cond.clone()));
        println!(
            "6p Result: is_win={}, Shape={}, Han={}, Yaku={:?}",
            res6p.is_win, res6p.has_win_shape, res6p.han, res6p.yaku
        );
        assert!(!res6p.is_win, "6p should NOT be a win (No Yaku)");
        assert!(res6p.has_win_shape, "6p should have win shape");
        assert_eq!(res6p.han, 0, "6p should have 0 Han");

        // 2. Check 9p (17 -> 68)
        let res9p = calc.calc(68, vec![], vec![], Some(cond));
        println!(
            "9p Result: is_win={}, Han={}, Yaku={:?}",
            res9p.is_win, res9p.han, res9p.yaku
        );
        assert!(res9p.is_win, "9p should be a win");
        assert!(res9p.han >= 3, "9p should be Junchan (>= 3 Han)"); // Junchan (3)
    }

    #[test]
    fn test_tobi_ends_game() {
        let mut state = create_test_state(2);

        // Set scores with one player having negative score
        state.players[0].score = 30000;
        state.players[1].score = 40000;
        state.players[2].score = 35000;
        state.players[3].score = -5000; // Negative score - should trigger tobi

        state.needs_initialize_next_round = false;

        // Try to initialize next round - should end game due to tobi
        state._initialize_next_round(false, false);

        assert!(
            state.is_done,
            "Game should be done due to tobi (player with negative score)"
        );

        // Verify MJAI log contains end_kyoku followed by end_game
        let log = &state.mjai_log;
        let ek_pos = log.iter().position(|s| s.contains("\"end_kyoku\""));
        let eg_pos = log.iter().position(|s| s.contains("\"end_game\""));
        assert!(
            ek_pos.is_some(),
            "end_kyoku must be emitted before end_game on tobi"
        );
        assert!(eg_pos.is_some(), "end_game must be emitted on tobi");
        assert!(
            ek_pos.unwrap() < eg_pos.unwrap(),
            "end_kyoku must appear before end_game"
        );
    }

    #[test]
    fn test_oyayame_requires_target_in_orasu_4p() {
        let mut state = create_test_state(2);
        state.round_wind = 1;
        state.oya = 3;
        state.players[0].score = 28900;
        state.players[1].score = 20000;
        state.players[2].score = 20100;
        state.players[3].score = 29000;

        state._initialize_next_round(true, false);

        assert!(
            !state.is_done,
            "Game should continue if the orasu dealer is top but below 30000"
        );
    }

    #[test]
    fn test_apply_mjai_event_honor_and_red_tiles() {
        use crate::replay::MjaiEvent;

        let mut state =
            crate::state::GameState::new(2, true, None, 0, crate::rule::GameRule::default());

        // start_kyoku with mjai-format tiles: honors (E, S, W, N, P, F, C) and red fives (5pr, 5sr)
        let start = MjaiEvent::StartKyoku {
            bakaze: "E".to_string(),
            kyoku: 1,
            honba: 0,
            kyoutaku: 0,
            oya: 0,
            scores: vec![25000, 25000, 25000, 25000],
            dora_marker: "P".to_string(), // White dragon (tid 124)
            tehais: vec![
                // Player 0: E, S, W, N, P, F, C, 1m, 2m, 3m, 4m, 5m, 6m
                vec![
                    "E", "S", "W", "N", "P", "F", "C", "1m", "2m", "3m", "4m", "5m", "6m",
                ]
                .into_iter()
                .map(String::from)
                .collect(),
                // Player 1: 1s, 2s, 3s, 4s, 5sr, 6s, 7s, 8s, 9s, 1p, 2p, 3p, 4p
                vec![
                    "1s", "2s", "3s", "4s", "5sr", "6s", "7s", "8s", "9s", "1p", "2p", "3p", "4p",
                ]
                .into_iter()
                .map(String::from)
                .collect(),
                // Player 2: 5pr, 1m, 2m, 3m, 4m, 6m, 7m, 8m, 9m, 1p, 2p, 3p, 4p
                vec![
                    "5pr", "1m", "2m", "3m", "4m", "6m", "7m", "8m", "9m", "1p", "2p", "3p", "4p",
                ]
                .into_iter()
                .map(String::from)
                .collect(),
                // Player 3: all number tiles
                vec![
                    "1s", "2s", "3s", "4s", "5s", "6s", "7s", "8s", "9s", "1m", "2m", "3m", "4m",
                ]
                .into_iter()
                .map(String::from)
                .collect(),
            ],
        };
        state.apply_mjai_event(start);

        // Player 0: verify honor tiles are parsed correctly
        let hand0 = &state.players[0].hand;
        // E=108, S=112, W=116, N=120, P=124, F=128, C=132
        assert!(
            hand0.contains(&108),
            "E should be tid 108, hand: {:?}",
            hand0
        );
        assert!(
            hand0.contains(&112),
            "S should be tid 112, hand: {:?}",
            hand0
        );
        assert!(
            hand0.contains(&116),
            "W should be tid 116, hand: {:?}",
            hand0
        );
        assert!(
            hand0.contains(&120),
            "N should be tid 120, hand: {:?}",
            hand0
        );
        assert!(
            hand0.contains(&124),
            "P should be tid 124, hand: {:?}",
            hand0
        );
        assert!(
            hand0.contains(&128),
            "F should be tid 128, hand: {:?}",
            hand0
        );
        assert!(
            hand0.contains(&132),
            "C should be tid 132, hand: {:?}",
            hand0
        );

        // Player 1: verify red 5s (5sr = tid 88)
        let hand1 = &state.players[1].hand;
        assert!(
            hand1.contains(&88),
            "5sr should be tid 88, hand: {:?}",
            hand1
        );

        // Player 2: verify red 5p (5pr = tid 52)
        let hand2 = &state.players[2].hand;
        assert!(
            hand2.contains(&52),
            "5pr should be tid 52, hand: {:?}",
            hand2
        );

        // Dora marker "P" should be tid 124
        assert_eq!(
            state.wall.dora_indicators[0], 124,
            "dora_marker P should be tid 124, got: {}",
            state.wall.dora_indicators[0]
        );

        // Test tsumo with honor tile
        let tsumo = MjaiEvent::Tsumo {
            actor: 0,
            pai: "C".to_string(), // Red dragon (tid 132)
        };
        state.apply_mjai_event(tsumo);
        assert!(
            state.players[0].hand.contains(&132),
            "Tsumo C should add tid 132 to hand, hand: {:?}",
            state.players[0].hand
        );

        // Test dahai with honor tile
        let dahai = MjaiEvent::Dahai {
            actor: 0,
            pai: "E".to_string(), // East (tid 108)
            tsumogiri: false,
        };
        state.apply_mjai_event(dahai);
        assert!(
            state.players[0].discards.contains(&108),
            "Dahai E should discard tid 108, discards: {:?}",
            state.players[0].discards
        );

        // Test dora event with mjai honor
        let dora = MjaiEvent::Dora {
            dora_marker: "F".to_string(), // Green dragon (tid 128)
        };
        state.apply_mjai_event(dora);
        assert_eq!(
            state.wall.dora_indicators[1], 128,
            "dora F should be tid 128, got: {}",
            state.wall.dora_indicators[1]
        );
    }

    #[test]
    fn test_apply_mjai_event_start_kyoku_resets_pre_tsumo_wall_4p() {
        use crate::replay::MjaiEvent;

        let mut state =
            crate::state::GameState::new(2, true, None, 0, crate::rule::GameRule::default());

        assert_eq!(
            state.wall.tiles.len(),
            83,
            "fresh state should start post-tsumo"
        );

        state.apply_mjai_event(MjaiEvent::StartKyoku {
            bakaze: "E".to_string(),
            kyoku: 1,
            honba: 0,
            kyoutaku: 0,
            oya: 0,
            scores: vec![25000, 25000, 25000, 25000],
            dora_marker: "1m".to_string(),
            tehais: vec![
                vec!["1m".to_string(); 13],
                vec!["2m".to_string(); 13],
                vec!["3m".to_string(); 13],
                vec!["4m".to_string(); 13],
            ],
        });

        assert_eq!(
            state.wall.tiles.len(),
            84,
            "start_kyoku should rewind to pre-tsumo"
        );
        assert!(state.needs_tsumo, "dealer draw should still be pending");
        assert!(state.drawn_tile.is_none(), "no tile should be drawn yet");

        state.apply_mjai_event(MjaiEvent::Tsumo {
            actor: 0,
            pai: "5m".to_string(),
        });

        assert_eq!(
            state.wall.tiles.len(),
            83,
            "first tsumo should consume exactly one tile"
        );
    }

    #[test]
    fn test_apply_mjai_event_start_kyoku_resets_pre_tsumo_wall_3p() {
        use crate::replay::MjaiEvent;

        let mut state =
            crate::state_3p::GameState3P::new(5, true, None, 0, crate::rule::GameRule::default());

        assert_eq!(
            state.wall.tiles.len(),
            68,
            "fresh sanma state should start post-tsumo"
        );

        state.apply_mjai_event(MjaiEvent::StartKyoku {
            bakaze: "E".to_string(),
            kyoku: 1,
            honba: 0,
            kyoutaku: 0,
            oya: 0,
            scores: vec![35000, 35000, 35000],
            dora_marker: "1p".to_string(),
            tehais: vec![
                vec!["1p".to_string(); 13],
                vec!["2p".to_string(); 13],
                vec!["3p".to_string(); 13],
            ],
        });

        assert_eq!(
            state.wall.tiles.len(),
            69,
            "sanma start_kyoku should rewind to pre-tsumo"
        );
        assert!(state.needs_tsumo, "dealer draw should still be pending");
        assert!(state.drawn_tile.is_none(), "no tile should be drawn yet");

        state.apply_mjai_event(MjaiEvent::Tsumo {
            actor: 0,
            pai: "4p".to_string(),
        });

        assert_eq!(
            state.wall.tiles.len(),
            68,
            "first tsumo should consume exactly one tile"
        );
    }

    #[test]
    fn test_reach_to_mjai_includes_actor() {
        use crate::action::{Action, ActionType};

        // actor が Some のとき、to_mjai() の JSON に "actor" が含まれること
        let action = Action::new(ActionType::Riichi, None, vec![], Some(2));
        let json_str = action.to_mjai();
        let v: serde_json::Value = serde_json::from_str(&json_str).unwrap();
        assert_eq!(v["type"], "reach");
        assert_eq!(v["actor"], 2, "reach event should contain actor=2");

        // actor が None のとき、"actor" キーが存在しないこと
        let action_no_actor = Action::new(ActionType::Riichi, None, vec![], None);
        let json_str2 = action_no_actor.to_mjai();
        let v2: serde_json::Value = serde_json::from_str(&json_str2).unwrap();
        assert_eq!(v2["type"], "reach");
        assert!(
            v2.get("actor").is_none(),
            "reach event without actor should not have actor key"
        );
    }

    #[test]
    fn test_reach_accepted_mjai_includes_actor() {
        use crate::action::{Action, ActionType};
        use std::collections::HashMap;

        // リーチ宣言→打牌→他家パスの流れで reach_accepted イベントが生成され、
        // actor が正しく含まれることを確認する
        let mut state = create_test_state(2);
        let pid: u8 = state.current_player;
        let pid_us = pid as usize;

        // テンパイ形の手牌を構築 (14枚 = 13 + ツモ牌):
        //   123m 456m 789m 12p 11s + ツモ 5sr(88)
        //   5sr を切ると 123456789m 12p 11s → 3p 待ちテンパイ
        state.players[pid_us].hand = vec![0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 72, 73, 88];
        state.players[pid_us].hand.sort();
        state.players[pid_us].melds.clear();
        state.players[pid_us].score = 25000;
        state.players[pid_us].riichi_declared = false;
        state.players[pid_us].riichi_stage = false;
        state.players[pid_us].forbidden_discards.clear();
        state.drawn_tile = Some(88);
        state.phase = Phase::WaitAct;
        state.active_players = vec![pid];

        // Step 1: リーチ宣言 (tile=None)
        let mut actions = HashMap::new();
        actions.insert(pid, Action::new(ActionType::Riichi, None, vec![], None));
        state.step(&actions);

        // Step 2: 打牌 5sr(88) — リーチ宣言後の捨て牌
        let mut actions2 = HashMap::new();
        actions2.insert(
            pid,
            Action::new(ActionType::Discard, Some(88), vec![], None),
        );
        state.step(&actions2);

        // 他家にクレームがある場合は WaitResponse → 全員パス
        if state.phase == Phase::WaitResponse {
            let mut pass_actions = HashMap::new();
            for &ap in &state.active_players.clone() {
                pass_actions.insert(ap, Action::new(ActionType::Pass, None, vec![], None));
            }
            state.step(&pass_actions);
        }

        // mjai_log から reach_accepted イベントを探す
        let reach_accepted_event = state.mjai_log.iter().find_map(|s| {
            let v: serde_json::Value = serde_json::from_str(s).ok()?;
            if v["type"] == "reach_accepted" {
                Some(v)
            } else {
                None
            }
        });

        assert!(
            reach_accepted_event.is_some(),
            "mjai_log should contain a reach_accepted event. Log: {:?}",
            state.mjai_log
        );

        let v = reach_accepted_event.unwrap();
        assert_eq!(
            v["actor"],
            serde_json::Value::Number(pid.into()),
            "reach_accepted event should contain actor={}",
            pid
        );

        // riichi_pending_acceptance がクリアされていること
        assert!(state.riichi_pending_acceptance.is_none());
    }

    #[test]
    fn test_no_tobi_with_positive_scores() {
        let mut state = create_test_state(2);
        state.game_mode = 2; // 4p-red-half (Hanchan)
        state.round_wind = 0; // East round

        // Set scores with all players having positive scores
        state.players[0].score = 25000;
        state.players[1].score = 25000;
        state.players[2].score = 25000;
        state.players[3].score = 25000;

        state.needs_initialize_next_round = false;

        // Try to initialize next round - should NOT end game
        state._initialize_next_round(false, false);

        assert!(
            !state.is_done,
            "Game should NOT be done (all players have positive scores)"
        );
    }

    // ========== Sanma (3-player mahjong) Tests ==========

    fn create_sanma_test_state(game_type: u8) -> crate::state_3p::GameState3P {
        crate::state_3p::GameState3P::new(
            game_type,
            false,
            None,
            0,
            crate::rule::GameRule::default(),
        )
    }

    #[test]
    fn test_sanma_game_mode_config() {
        use crate::state_3p::game_mode;

        assert_eq!(game_mode::num_players(), 3);
        assert_eq!(game_mode::starting_score(), 35000);
        assert_eq!(game_mode::tenpai_pool(), 2000);
    }

    #[test]
    fn test_oyayame_requires_target_in_orasu_3p() {
        let mut state = create_sanma_test_state(5);
        state.round_wind = 1;
        state.oya = 2;
        state.players[0].score = 34900;
        state.players[1].score = 34000;
        state.players[2].score = 35100;

        state._initialize_next_round(true, false);

        assert!(
            !state.is_done,
            "Sanma should continue if the final dealer is top but below 40000"
        );
    }

    #[test]
    fn test_sanma_starting_scores() {
        let state = create_sanma_test_state(3);
        assert_eq!(state.players.len(), 3, "Should have exactly 3 players");
        for p in &state.players {
            assert_eq!(p.score, 35000, "Each player should start with 35000");
        }
    }

    #[test]
    fn test_sanma_wall_108_tiles() {
        let state = create_sanma_test_state(3);

        let total_tiles =
            state.wall.tiles.len() + state.players.iter().map(|p| p.hand.len()).sum::<usize>();
        assert_eq!(total_tiles, 108, "Total tiles should be 108 for sanma");

        // Verify no manzu 2-8 tiles (tile types 1-7, tile IDs 4-31)
        for p in &state.players {
            for &t in &p.hand {
                let tile_type = t / 4;
                assert!(
                    !(1..=7).contains(&tile_type),
                    "Hand should not contain manzu 2-8 (tile type {}), but found tile {}",
                    tile_type,
                    t
                );
            }
        }
        for &t in &state.wall.tiles {
            let tile_type = t / 4;
            assert!(
                !(1..=7).contains(&tile_type),
                "Wall should not contain manzu 2-8 (tile type {}), but found tile {}",
                tile_type,
                t
            );
        }
    }

    #[test]
    fn test_sanma_deal_3_players() {
        let state = create_sanma_test_state(3);

        assert_eq!(state.players.len(), 3);
        assert_eq!(
            state.players[0].hand.len(),
            14,
            "Oya (player 0) should have 14 tiles after deal"
        );
        for i in 1..3 {
            assert_eq!(
                state.players[i].hand.len(),
                13,
                "Player {} should have 13 tiles after deal",
                i
            );
        }
    }

    #[test]
    fn test_sanma_no_chi() {
        use crate::action::{Action, ActionType};
        use crate::state_3p::legal_actions::GameState3PLegalActions;
        use std::collections::HashMap;

        let mut state = create_sanma_test_state(5); // 3p-red-half
        state._initialize_round(0, 0, 0, 0, None, None);

        // Give player 1 a sequential hand that could chi
        state.players[1].hand = vec![36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 76, 80, 84];
        state.current_player = 0;
        state.drawn_tile = Some(state.players[0].hand[0]);
        state.phase = Phase::WaitAct;
        state.active_players = vec![0];
        state.needs_tsumo = false;

        let discard_tile = state.players[0].hand[0];
        let mut actions = HashMap::new();
        actions.insert(
            0,
            Action::new(ActionType::Discard, Some(discard_tile), vec![], None),
        );
        state.step(&actions);

        let legal = state._get_legal_actions_internal(1);
        let has_chi = legal.iter().any(|a| a.action_type == ActionType::Chi);
        assert!(!has_chi, "Chi should not be available in sanma");
    }

    #[test]
    fn test_sanma_player_rotation() {
        let state = create_sanma_test_state(3);
        let np = state.np() as u8;

        // In sanma, players cycle 0 → 1 → 2 → 0
        assert_eq!(1u8 % np, 1, "Next player after 0 should be 1");
        assert_eq!((1u8 + 1) % np, 2, "Next player after 1 should be 2");
        assert_eq!((2u8 + 1) % np, 0, "Next player after 2 should be 0");
    }

    #[test]
    fn test_sanma_kita_action() {
        use crate::action::ActionType;
        use crate::state_3p::legal_actions::GameState3PLegalActions;

        let mut state = create_sanma_test_state(3);
        state._initialize_round(0, 0, 0, 0, None, None);

        state.players[0].hand = vec![0, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 76, 120];
        state.drawn_tile = Some(120);
        state.current_player = 0;
        state.phase = Phase::WaitAct;
        state.active_players = vec![0];
        state.needs_tsumo = false;

        let legal = state._get_legal_actions_internal(0);
        let has_kita = legal.iter().any(|a| a.action_type == ActionType::Kita);
        assert!(
            has_kita,
            "Kita should be available when holding North tile in sanma"
        );
    }

    #[test]
    fn test_sanma_dora_wrapping() {
        use crate::state_3p::game_mode;

        // 1m (type 0) → 9m (type 8)
        assert_eq!(game_mode::get_next_dora_tile(0), 8);
        // 9m (type 8) → 1m (type 0)
        assert_eq!(game_mode::get_next_dora_tile(8), 0);
        // Pin/sou/honor wrapping should be standard
        assert_eq!(game_mode::get_next_dora_tile(9), 10); // 1p → 2p
        assert_eq!(game_mode::get_next_dora_tile(17), 9); // 9p → 1p
        assert_eq!(game_mode::get_next_dora_tile(27), 28); // East → South
        assert_eq!(game_mode::get_next_dora_tile(30), 27); // North → East
    }

    #[test]
    fn test_sanma_tsumo_scoring() {
        let score = calculate_score(4, 30, false, true, 0, 3); // Ko Tsumo, 3 players
        assert_eq!(score.pay_tsumo_oya, 3900);
        assert_eq!(score.pay_tsumo_ko, 2000);
        assert_eq!(
            score.total, 5900,
            "3P tsumo total should be 5900 (2 payers)"
        );
    }

    #[test]
    fn test_sanma_tenpai_payment() {
        use crate::state_3p::game_mode;
        assert_eq!(
            game_mode::tenpai_pool(),
            2000,
            "Sanma tenpai pool should be 2000"
        );
    }

    #[test]
    fn test_ryukyoku_deltas_are_reset_each_round_3p() {
        use serde_json::Value;

        let mut state = create_sanma_test_state(5);

        state.players[0].score_delta = 2300;
        state.players[1].score_delta = -2300;
        state.players[2].score_delta = 0;

        state._initialize_round(0, 0, 0, 0, None, None);
        state._trigger_ryukyoku("suukansansen");

        let v: Value = state
            .mjai_log
            .iter()
            .rev()
            .find_map(|s| {
                let ev: Value = serde_json::from_str(s).ok()?;
                (ev["type"] == "ryukyoku").then_some(ev)
            })
            .expect("ryukyoku event should be logged");
        assert_eq!(v["reason"], "suukansansen");

        let deltas: Vec<i32> = serde_json::from_value(v["deltas"].clone()).expect("deltas");
        assert_eq!(deltas, vec![0, 0, 0]);
    }

    // ========== Action Encode Tests (4P/3P) ==========

    #[test]
    fn test_action_encode_4p_discard() {
        use crate::action::{Action, ActionType};

        // tile 0 (1m, type 0) → ID 0
        let a = Action::new(ActionType::Discard, Some(0), vec![], None);
        assert_eq!(a.encode().unwrap(), 0);

        // tile 4 (2m, type 1) → ID 1
        let a = Action::new(ActionType::Discard, Some(4), vec![], None);
        assert_eq!(a.encode().unwrap(), 1);

        // tile 132 (C/7z, type 33) → ID 33
        let a = Action::new(ActionType::Discard, Some(132), vec![], None);
        assert_eq!(a.encode().unwrap(), 33);
    }

    #[test]
    fn test_action_encode_4p_special() {
        use crate::action::{Action, ActionType};

        assert_eq!(
            Action::new(ActionType::Riichi, None, vec![], None)
                .encode()
                .unwrap(),
            37
        );
        assert_eq!(
            Action::new(ActionType::Pon, None, vec![], None)
                .encode()
                .unwrap(),
            41
        );
        // Daiminkan tile 0 (1m) → 42 + 0 = 42
        assert_eq!(
            Action::new(ActionType::Daiminkan, Some(0), vec![], None)
                .encode()
                .unwrap(),
            42
        );
        assert_eq!(
            Action::new(ActionType::Ron, None, vec![], None)
                .encode()
                .unwrap(),
            79
        );
        assert_eq!(
            Action::new(ActionType::KyushuKyuhai, None, vec![], None)
                .encode()
                .unwrap(),
            80
        );
        assert_eq!(
            Action::new(ActionType::Pass, None, vec![], None)
                .encode()
                .unwrap(),
            81
        );
        // Kita is not valid in 4P mode
        assert!(
            Action::new(ActionType::Kita, None, vec![], None)
                .encode()
                .is_err()
        );
    }

    #[test]
    fn test_action_encode_3p_discard() {
        use crate::action::{Action, ActionEncoder, ActionType};
        let enc = ActionEncoder::ThreePlayer;

        // 1m (type 0) → compact 0
        let a = Action::new(ActionType::Discard, Some(0), vec![], None);
        assert_eq!(enc.encode(&a).unwrap(), 0);

        // 9m (type 8, tile 32) → compact 1
        let a = Action::new(ActionType::Discard, Some(32), vec![], None);
        assert_eq!(enc.encode(&a).unwrap(), 1);

        // 1p (type 9, tile 36) → compact 2
        let a = Action::new(ActionType::Discard, Some(36), vec![], None);
        assert_eq!(enc.encode(&a).unwrap(), 2);

        // 9p (type 17, tile 68) → compact 10
        let a = Action::new(ActionType::Discard, Some(68), vec![], None);
        assert_eq!(enc.encode(&a).unwrap(), 10);

        // 1s (type 18, tile 72) → compact 11
        let a = Action::new(ActionType::Discard, Some(72), vec![], None);
        assert_eq!(enc.encode(&a).unwrap(), 11);

        // C (type 33, tile 132) → compact 26
        let a = Action::new(ActionType::Discard, Some(132), vec![], None);
        assert_eq!(enc.encode(&a).unwrap(), 26);
    }

    #[test]
    fn test_action_encode_3p_special() {
        use crate::action::{Action, ActionEncoder, ActionType};
        let enc = ActionEncoder::ThreePlayer;

        assert_eq!(
            enc.encode(&Action::new(ActionType::Riichi, None, vec![], None))
                .unwrap(),
            27
        );
        assert_eq!(
            enc.encode(&Action::new(ActionType::Pon, None, vec![], None))
                .unwrap(),
            28
        );
        // Kan 1m (type 0) → 29 + 0 = 29
        assert_eq!(
            enc.encode(&Action::new(ActionType::Daiminkan, Some(0), vec![], None))
                .unwrap(),
            29
        );
        // Kan 9m (type 8, tile 32) → 29 + 1 = 30
        assert_eq!(
            enc.encode(&Action::new(ActionType::Daiminkan, Some(32), vec![], None))
                .unwrap(),
            30
        );
        // Kan C (type 33, tile 132) → 29 + 26 = 55
        assert_eq!(
            enc.encode(&Action::new(ActionType::Ankan, None, vec![132], None))
                .unwrap(),
            55
        );
        assert_eq!(
            enc.encode(&Action::new(ActionType::Ron, None, vec![], None))
                .unwrap(),
            56
        );
        assert_eq!(
            enc.encode(&Action::new(ActionType::KyushuKyuhai, None, vec![], None))
                .unwrap(),
            57
        );
        assert_eq!(
            enc.encode(&Action::new(ActionType::Pass, None, vec![], None))
                .unwrap(),
            58
        );
        assert_eq!(
            enc.encode(&Action::new(ActionType::Kita, None, vec![], None))
                .unwrap(),
            59
        );
    }

    #[test]
    fn test_action_encode_3p_invalid_manzu() {
        use crate::action::{Action, ActionEncoder, ActionType};
        let enc = ActionEncoder::ThreePlayer;

        // 2m (type 1, tile 4) should be invalid in 3P
        let a = Action::new(ActionType::Discard, Some(4), vec![], None);
        assert!(enc.encode(&a).is_err());

        // 5m (type 4, tile 16) should be invalid in 3P
        let a = Action::new(ActionType::Discard, Some(16), vec![], None);
        assert!(enc.encode(&a).is_err());

        // 8m (type 7, tile 28) should be invalid in 3P
        let a = Action::new(ActionType::Discard, Some(28), vec![], None);
        assert!(enc.encode(&a).is_err());
    }

    #[test]
    fn test_action_encode_3p_chi_not_allowed() {
        use crate::action::{Action, ActionEncoder, ActionType};
        let enc = ActionEncoder::ThreePlayer;

        let a = Action::new(ActionType::Chi, Some(36), vec![40, 44], None);
        assert!(enc.encode(&a).is_err());
    }

    #[test]
    fn test_action_space_size() {
        use crate::action::ActionEncoder;

        assert_eq!(ActionEncoder::FourPlayer.action_space_size(), 82);
        assert_eq!(ActionEncoder::ThreePlayer.action_space_size(), 60);
        assert_eq!(ActionEncoder::from_num_players(4).action_space_size(), 82);
        assert_eq!(ActionEncoder::from_num_players(3).action_space_size(), 60);
    }

    #[test]
    fn test_3p_encode_all_discard_ids_contiguous() {
        use crate::action::{Action, ActionEncoder, ActionType};
        let enc = ActionEncoder::ThreePlayer;

        // All 27 valid tile types in 3P should map to discard IDs 0-26 contiguously
        let valid_types: Vec<u8> = vec![
            0, 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,
        ];
        assert_eq!(valid_types.len(), 27);

        let mut ids: Vec<i32> = Vec::new();
        for &tile_type in &valid_types {
            let tile_136 = tile_type * 4;
            let a = Action::new(ActionType::Discard, Some(tile_136), vec![], None);
            ids.push(enc.encode(&a).unwrap());
        }

        ids.sort();
        let expected: Vec<i32> = (0..27).collect();
        assert_eq!(ids, expected, "3P discard IDs should be contiguous 0-26");
    }

    #[test]
    fn test_sanma_observation_num_players() {
        let mut state = create_sanma_test_state(3);
        state._initialize_round(0, 0, 0, 0, None, None);

        state.drawn_tile = Some(state.players[0].hand[0]);
        state.current_player = 0;
        state.phase = Phase::WaitAct;
        state.active_players = vec![0];
        state.needs_tsumo = false;

        let obs = state.get_observation(0);
        // hands, scores, discards, melds are now [T; 3] fixed-size arrays,
        // so .len() checks are trivially true and have been removed.
        assert!(
            !obs.hands[0].is_empty(),
            "Player 0 hand should not be empty"
        );
    }

    // ========== Yakuman Scoring & PAO Tests ==========

    #[test]
    fn test_kazoe_yakuman_score_boundary() {
        // calculate_score uses `8000 * (han / 13)` for han >= 13.
        // han 13 → single yakuman (8000 base)
        let s13 = calculate_score(13, 0, false, false, 0, 4);
        assert_eq!(s13.pay_ron, 32000, "han=13 ko ron should be 32000");

        // han 14 → 8000*(14/13) = 8000*1 = still single yakuman
        let s14 = calculate_score(14, 0, false, false, 0, 4);
        assert_eq!(s14.pay_ron, 32000, "han=14 ko ron should still be 32000");

        // han 25 → 8000*(25/13) = 8000*1 = still single yakuman
        let s25 = calculate_score(25, 0, false, false, 0, 4);
        assert_eq!(s25.pay_ron, 32000, "han=25 ko ron should still be 32000");

        // han 26 → 8000*(26/13) = 8000*2 = double yakuman
        let s26 = calculate_score(26, 0, false, false, 0, 4);
        assert_eq!(s26.pay_ron, 64000, "han=26 ko ron should be 64000");

        // Oya equivalents
        let s13_oya = calculate_score(13, 0, true, false, 0, 4);
        assert_eq!(s13_oya.pay_ron, 48000, "han=13 oya ron should be 48000");

        let s26_oya = calculate_score(26, 0, true, false, 0, 4);
        assert_eq!(s26_oya.pay_ron, 96000, "han=26 oya ron should be 96000");
    }

    #[test]
    fn test_kazoe_yakuman_hand_evaluator_cap() {
        use crate::hand_evaluator::HandEvaluator;
        use crate::types::{Conditions, Wind};

        // Build a hand with 14+ han but no yakuman yaku:
        // Chinitsu (6) + Pinfu (1) + Iipeiko (1) + Riichi (1) + Tsumo (1) + Ippatsu (1) + Dora 3
        // = 14 han. Should be capped to single yakuman, NOT double.
        //
        // Hand: 112233 456 789 m + 55m pair (all manzu = chinitsu)
        // 1m=0, 2m=1, 3m=2, 4m=3, 5m=4, 6m=5, 7m=6, 8m=7, 9m=8
        // 136-tile: 1m=0,1; 2m=4,5; 3m=8,9; 4m=12; 5m=16(red); 6m=20; 7m=24; 8m=28; 9m=32; 5m=17(pair)
        let tiles_136 = vec![
            0, 1, // 1m x2
            4, 5, // 2m x2
            8, 9,  // 3m x2
            12, // 4m
            16, // 5m (red → 1 aka dora)
            20, // 6m
            24, // 7m
            28, // 8m
            32, // 9m
            17, // 5m (pair piece 1)
        ];

        let calc = HandEvaluator::new(tiles_136, Vec::new());

        let cond = Conditions {
            tsumo: true,
            riichi: true,
            ippatsu: true,
            player_wind: Wind::South,
            round_wind: Wind::East,
            ..Default::default()
        };

        // Win tile: 5m (tile 18 in 136-format → type 4)
        // This completes the 55m pair.
        // Dora indicators: set 3 indicators that produce dora on tiles we hold.
        // Indicator 0m (tile_type=0, but 0-1 → next=1m). Use 3m indicator → dora is 4m.
        // Indicator for 3m = tile 8..11 → next tile type is 4 (4m). We hold 4m.
        // Let's use 3 copies of 3m indicator so dora count = 3 (we hold one 4m).
        // Actually to get 3 dora, let's use indicator pointing to a tile we hold multiple of.
        // Indicator 0m (type 0) → dora is 1m (type 0+1=1... wait, 0→1 means 2m).
        // get_next_tile: if tile < 9, tile == 8 → 0, else tile+1
        // So indicator type 0 (1m) → dora type 1 (2m). We hold 2x 2m = 2 dora.
        // Indicator type 1 (2m) → dora type 2 (3m). We hold 2x 3m = 2 dora.
        // Indicator type 3 (4m) → dora type 4 (5m). We hold 2x 5m in hand = 2 dora.
        // With aka 5m (red) that's +1 aka_dora.
        // So: chinitsu(6) + pinfu(1) + iipeiko(1) + riichi(1) + tsumo(1) + ippatsu(1) + 2 dora + 1 aka = 14 han
        // indicator type 0 (1m) → dora type 1 (2m), we hold 2 copies = 2 dora.
        // Plus 1 aka dora from red 5m.
        // chinitsu(6) + pinfu(1) + iipeiko(1) + riichi(1) + tsumo(1) + ippatsu(1) + 2 dora + 1 aka = 14
        let dora_indicators = vec![0]; // type 0 → dora type 1 (2m), we hold 2
        let res = calc.calc(18, dora_indicators, vec![], Some(cond));

        assert!(res.is_win, "Should be a winning hand");
        assert!(
            !res.yakuman,
            "Should NOT be flagged as yakuman (it's kazoe)"
        );
        // han should be reported as the raw total (>=14), but scores capped at single yakuman
        assert!(res.han >= 14, "Raw han should be >= 14, got {}", res.han);

        // Ko tsumo: single yakuman = base 8000 → oya pays 16000, ko pays 8000
        assert_eq!(
            res.tsumo_agari_oya, 16000,
            "Kazoe yakuman tsumo: oya should pay 16000"
        );
        assert_eq!(
            res.tsumo_agari_ko, 8000,
            "Kazoe yakuman tsumo: ko should pay 8000"
        );
    }

    #[test]
    fn test_daiminkan_pao_daisangen() {
        use crate::action::{Action, ActionType};
        use crate::types::{Meld, MeldType};

        let mut state = create_test_state(2);
        state._initialize_next_round(true, false);

        let pid: u8 = 0;

        // Give player 0 two open dragon pon melds (haku=31, hatsu=32).
        // Tiles in melds use 34-tile notation.
        state.players[0].melds = vec![
            Meld {
                meld_type: MeldType::Pon,
                tiles: vec![124, 125, 126], // haku (31*4=124)
                opened: true,
                from_who: 1,
                called_tile: Some(124),
            },
            Meld {
                meld_type: MeldType::Pon,
                tiles: vec![128, 129, 130], // hatsu (32*4=128)
                opened: true,
                from_who: 2,
                called_tile: Some(128),
            },
        ];

        // Player 3 discards chun (33*4=132). Player 0 calls daiminkan.
        let discarder: u8 = 3;
        state.last_discard = Some((discarder, 132));

        // consume_tiles = the 3 chun tiles from hand (we use 133,134,135)
        let action = Action::new(
            ActionType::Daiminkan,
            Some(132),
            vec![133, 134, 135],
            Some(pid),
        );

        state._resolve_kan(pid, action);

        // PAO should be set: yaku 37 (daisangen) → discarder 3
        assert_eq!(
            state.players[0].pao.get(&37),
            Some(&discarder),
            "Daisangen PAO should point to discarder {}",
            discarder
        );
    }

    #[test]
    fn test_daiminkan_pao_daisuushii() {
        use crate::action::{Action, ActionType};
        use crate::types::{Meld, MeldType};

        let mut state = create_test_state(2);
        state._initialize_next_round(true, false);

        let pid: u8 = 0;

        // Give player 0 three open wind pon melds (E=27, S=28, W=29).
        state.players[0].melds = vec![
            Meld {
                meld_type: MeldType::Pon,
                tiles: vec![108, 109, 110], // E (27*4=108)
                opened: true,
                from_who: 1,
                called_tile: Some(108),
            },
            Meld {
                meld_type: MeldType::Pon,
                tiles: vec![112, 113, 114], // S (28*4=112)
                opened: true,
                from_who: 2,
                called_tile: Some(112),
            },
            Meld {
                meld_type: MeldType::Pon,
                tiles: vec![116, 117, 118], // W (29*4=116)
                opened: true,
                from_who: 3,
                called_tile: Some(116),
            },
        ];

        // Player 2 discards N (30*4=120). Player 0 calls daiminkan.
        let discarder: u8 = 2;
        state.last_discard = Some((discarder, 120));

        let action = Action::new(
            ActionType::Daiminkan,
            Some(120),
            vec![121, 122, 123],
            Some(pid),
        );

        state._resolve_kan(pid, action);

        // PAO should be set: yaku 50 (daisuushii) → discarder 2
        assert_eq!(
            state.players[0].pao.get(&50),
            Some(&discarder),
            "Daisuushii PAO should point to discarder {}",
            discarder
        );
    }

    #[test]
    fn test_daiminkan_no_pao_insufficient_melds() {
        use crate::action::{Action, ActionType};
        use crate::types::{Meld, MeldType};

        let mut state = create_test_state(2);
        state._initialize_next_round(true, false);

        let pid: u8 = 0;

        // Give player 0 only ONE dragon pon meld (haku=31).
        state.players[0].melds = vec![Meld {
            meld_type: MeldType::Pon,
            tiles: vec![124, 125, 126], // haku (31*4=124)
            opened: true,
            from_who: 1,
            called_tile: Some(124),
        }];

        // Player 1 discards hatsu (32*4=128). Player 0 calls daiminkan.
        // After this, player 0 has 2 dragon melds — NOT 3, so no PAO.
        let discarder: u8 = 1;
        state.last_discard = Some((discarder, 128));

        let action = Action::new(
            ActionType::Daiminkan,
            Some(128),
            vec![129, 130, 131],
            Some(pid),
        );

        state._resolve_kan(pid, action);

        // No PAO should be set (only 2 dragon melds, need 3)
        assert!(
            state.players[0].pao.is_empty(),
            "PAO should NOT be set with only 2 dragon melds, got: {:?}",
            state.players[0].pao
        );
    }

    #[test]
    fn test_ron_pao_50_50_split() {
        // Ron with PAO: pao player and discarder split total 50/50.
        // score / 2 goes to pao player, remainder to discarder.

        // Single yakuman ron by ko: 32000
        let score: i32 = 32000;
        let pao_amt = score / 2; // 16000
        let discarder_amt = score - pao_amt; // 16000
        assert_eq!(pao_amt, 16000);
        assert_eq!(discarder_amt, 16000);
        assert_eq!(pao_amt + discarder_amt, score, "Must sum to total score");

        // Double yakuman ron by ko: 64000
        let score2: i32 = 64000;
        let pao_amt2 = score2 / 2;
        let discarder_amt2 = score2 - pao_amt2;
        assert_eq!(pao_amt2, 32000);
        assert_eq!(discarder_amt2, 32000);
        assert_eq!(pao_amt2 + discarder_amt2, score2);

        // Single yakuman ron by oya: 48000
        let score3: i32 = 48000;
        let pao_amt3 = score3 / 2;
        let discarder_amt3 = score3 - pao_amt3;
        assert_eq!(pao_amt3, 24000);
        assert_eq!(discarder_amt3, 24000);
        assert_eq!(pao_amt3 + discarder_amt3, score3);

        // Simulate delta computation (as in state/mod.rs ron PAO logic):
        // winner w, pao_payer p, discarder d (all different)
        let (w, p, d) = (0usize, 1usize, 2usize);
        let mut deltas = [0i32; 4];
        deltas[w] += score;
        deltas[p] -= pao_amt;
        deltas[d] -= score - pao_amt;
        assert_eq!(deltas.iter().sum::<i32>(), 0, "Deltas must be zero-sum");
    }

    #[test]
    fn test_tsumo_pao_non_pao_split() {
        // Mixed PAO/non-PAO tsumo scoring (e.g. daisangen from PAO + another yakuman self-drawn).
        // pao_yakuman_val = 1 (daisangen), non_pao_yakuman_val = 1 (e.g. suuankou),
        // total_yakuman_val = 2.

        let np: usize = 4;
        let pao_yakuman_val: i32 = 1;
        let non_pao_yakuman_val: i32 = 1;

        // Case 1: Ko winner (pid=0, oya=1)
        {
            let pid = 0usize;
            let oya = 1usize;
            let pp = 3usize; // pao player

            let unit: i32 = 32000; // ko winner unit
            let honba_total: i32 = 0;
            let pao_amt = pao_yakuman_val * unit + honba_total; // 32000
            let oya_pay = non_pao_yakuman_val * 16000; // 16000
            let ko_pay = non_pao_yakuman_val * 8000; // 8000

            let mut deltas = vec![0i32; np];

            // PAO player pays pao portion
            deltas[pp] -= pao_amt;

            // Non-PAO split among other players
            for (i, delta) in deltas.iter_mut().enumerate().take(np) {
                if i != pid {
                    if i == oya {
                        *delta -= oya_pay;
                    } else if i != pp {
                        // non-oya, non-pao ko player
                        *delta -= ko_pay;
                    } else {
                        // pao player also pays ko share for non-pao part
                        *delta -= ko_pay;
                    }
                }
            }

            let total_win: i32 = -deltas.iter().filter(|&&d| d < 0).sum::<i32>();
            deltas[pid] += total_win;

            assert_eq!(
                deltas.iter().sum::<i32>(),
                0,
                "Ko winner tsumo PAO deltas must be zero-sum"
            );
            // PAO player pays: 32000 (pao) + 8000 (ko share of non-pao) = 40000
            assert_eq!(deltas[pp], -40000, "PAO player should pay 40000 total");
            // Oya pays: 16000 (oya share of non-pao)
            assert_eq!(deltas[oya], -16000, "Oya should pay 16000");
            // Remaining ko pays: 8000 (ko share of non-pao)
            let other_ko = (0..np).find(|&i| i != pid && i != oya && i != pp).unwrap();
            assert_eq!(deltas[other_ko], -8000, "Other ko should pay 8000");
            // Winner gets: 40000 + 16000 + 8000 = 64000
            assert_eq!(deltas[pid], 64000, "Winner should receive 64000");
        }

        // Case 2: Oya winner (pid=0, oya=0)
        {
            let pid = 0usize;
            let pp = 2usize; // pao player

            let unit: i32 = 48000; // oya winner unit
            let pao_amt = pao_yakuman_val * unit; // 48000
            let ko_share = non_pao_yakuman_val * 16000; // 16000 per non-oya player

            let mut deltas = vec![0i32; np];

            // PAO player pays pao portion
            deltas[pp] -= pao_amt;

            // Non-PAO split: each non-oya pays 16000
            for (i, delta) in deltas.iter_mut().enumerate().take(np) {
                if i != pid {
                    *delta -= ko_share;
                }
            }

            let total_win: i32 = -deltas.iter().filter(|&&d| d < 0).sum::<i32>();
            deltas[pid] += total_win;

            assert_eq!(
                deltas.iter().sum::<i32>(),
                0,
                "Oya winner tsumo PAO deltas must be zero-sum"
            );
            // PAO player pays: 48000 (pao) + 16000 (ko share) = 64000
            assert_eq!(deltas[pp], -64000, "PAO player should pay 64000 total");
            // Other ko players each pay 16000
            for (i, &delta) in deltas.iter().enumerate().take(np) {
                if i != pid && i != pp {
                    assert_eq!(delta, -16000, "Ko player {} should pay 16000", i);
                }
            }
            // Winner gets: 64000 + 16000 + 16000 = 96000
            assert_eq!(deltas[pid], 96000, "Oya winner should receive 96000");
        }
    }

    #[test]
    fn test_tenhou_tsumo_pao_composite() {
        // Tenhou rule (yakuman_pao_is_liability_only = false):
        // Double yakuman tsumo (1x PAO + 1x non-PAO) by ko player.
        // PAO pays ALL yakuman: total_yakuman_val * unit = 2 * 32000 = 64000.
        // Other players pay 0.

        let np: usize = 4;
        let pid = 0usize; // ko winner
        let oya = 1usize;
        let pp = 3usize; // pao player
        let total_yakuman_val: i32 = 2;
        let unit: i32 = 32000; // ko
        let honba_total: i32 = 0;

        // Tenhou: PAO pays everything
        let full_amt = total_yakuman_val * unit + honba_total; // 64000
        let mut deltas = vec![0i32; np];
        deltas[pp] -= full_amt;
        let total_win = full_amt;
        deltas[pid] += total_win;

        assert_eq!(deltas.iter().sum::<i32>(), 0, "Deltas must be zero-sum");
        assert_eq!(deltas[pp], -64000, "PAO player pays all 64000");
        assert_eq!(deltas[oya], 0, "Oya pays nothing under Tenhou PAO");
        let other_ko = (0..np).find(|&i| i != pid && i != oya && i != pp).unwrap();
        assert_eq!(
            deltas[other_ko], 0,
            "Other ko pays nothing under Tenhou PAO"
        );
        assert_eq!(deltas[pid], 64000, "Winner receives 64000");
    }

    #[test]
    fn test_tenhou_ron_pao_composite() {
        // Tenhou rule (yakuman_pao_is_liability_only = false):
        // Triple yakuman ron (2x PAO + 1x non-PAO) by oya.
        // Total: 3 * 48000 = 144000. Split 50/50 between PAO and discarder.
        // PAO pays 72000, discarder pays 72000.

        let np: usize = 4;
        let w_pid = 0usize; // oya winner
        let pao_payer = 1usize;
        let discarder = 2usize;
        let total_yakuman_val: i32 = 3;
        let unit: i32 = 48000; // oya
        let honba_ron: i32 = 0;

        // Tenhou: total score split 50/50
        let total_base = total_yakuman_val * unit; // 144000
        let pao_amt = total_base / 2 + honba_ron; // 72000
        let score = total_base + honba_ron; // 144000
        let discarder_amt = score - pao_amt; // 72000

        let mut deltas = vec![0i32; np];
        deltas[w_pid] += score;
        deltas[pao_payer] -= pao_amt;
        deltas[discarder] -= discarder_amt;

        assert_eq!(deltas.iter().sum::<i32>(), 0, "Deltas must be zero-sum");
        assert_eq!(pao_amt, 72000, "PAO pays half of total (72000)");
        assert_eq!(discarder_amt, 72000, "Discarder pays half of total (72000)");
        assert_eq!(deltas[w_pid], 144000, "Winner receives 144000");
    }

    #[test]
    fn test_mjsoul_3p_ron_pao_composite() {
        // 3P MjSoul rule (yakuman_pao_is_liability_only = true):
        // Double yakuman ron (1x PAO daisangen + 1x non-PAO tsuuiisou) by oya.
        // Total: 2 * 48000 = 96000. Only PAO portion split 50/50.
        // PAO pays 24000 (= 48000/2), discarder pays 72000 (= 48000/2 + 48000).

        let np: usize = 3;
        let w_pid = 0usize; // oya winner
        let pao_payer = 1usize;
        let discarder = 2usize;
        let pao_yakuman_val: i32 = 1;
        let total_yakuman_val: i32 = 2;
        let unit: i32 = 48000; // oya
        let honba_ron: i32 = 0;

        // 3P MjSoul: only PAO portion split 50/50
        let split_base = pao_yakuman_val * unit; // 48000
        let pao_amt = split_base / 2 + honba_ron; // 24000
        let score = total_yakuman_val * unit + honba_ron; // 96000
        let discarder_amt = score - pao_amt; // 72000

        let mut deltas = vec![0i32; np];
        deltas[w_pid] += score;
        deltas[pao_payer] -= pao_amt;
        deltas[discarder] -= discarder_amt;

        assert_eq!(deltas.iter().sum::<i32>(), 0, "Deltas must be zero-sum");
        assert_eq!(pao_amt, 24000, "PAO pays half of PAO portion (24000)");
        assert_eq!(
            discarder_amt, 72000,
            "Discarder pays half of PAO portion + full non-PAO (72000)"
        );
        assert_eq!(deltas[w_pid], 96000, "Winner receives 96000");
    }

    #[test]
    fn test_mjsoul_4p_ron_pao_composite() {
        // 4P MjSoul rule (yakuman_pao_is_liability_only = true):
        // Double yakuman ron (1x PAO daisangen + 1x non-PAO tsuuiisou) by ko.
        // Total: 2 * 32000 = 64000. PAO portion only split 50/50.
        // split_base = pao_yakuman_val * unit = 1 * 32000 = 32000
        // PAO pays 16000 (= 32000/2), discarder pays 48000 (= 64000 - 16000).

        let np: usize = 4;
        let w_pid = 0usize; // ko winner
        let pao_payer = 1usize;
        let discarder = 2usize;
        let total_yakuman_val: i32 = 2;
        let pao_yakuman_val: i32 = 1;
        let unit: i32 = 32000; // ko
        let honba_ron: i32 = 0;

        // 4P MjSoul: PAO portion only split 50/50 for Ron
        let split_base = pao_yakuman_val * unit; // 32000
        let pao_amt = split_base / 2 + honba_ron; // 16000
        let score = total_yakuman_val * unit + honba_ron; // 64000
        let discarder_amt = score - pao_amt; // 48000

        let mut deltas = vec![0i32; np];
        deltas[w_pid] += score;
        deltas[pao_payer] -= pao_amt;
        deltas[discarder] -= discarder_amt;

        assert_eq!(deltas.iter().sum::<i32>(), 0, "Deltas must be zero-sum");
        assert_eq!(pao_amt, 16000, "PAO pays half of PAO portion (16000)");
        assert_eq!(discarder_amt, 48000, "Discarder pays remainder (48000)");
        assert_eq!(deltas[w_pid], 64000, "Winner receives 64000");
    }
}