File size: 58,298 Bytes
87c8483
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
from __future__ import annotations

from loguru import logger
import numpy as np
import torch
from torch import nn

from gear_sonic.trl.utils import common


def set_fuzzy_config_params(config, candidate_keys, value):
    """Set matching config keys to a given value.

    Scans ``config`` for any key that appears in ``candidate_keys`` and
    overwrites its value.  Used to wire dynamically-computed dimensions
    (e.g. ``input_dim``, ``output_dim``) into encoder / decoder param
    dicts before instantiation.

    Args:
        config: Mutable mapping of parameter names to values.
        candidate_keys: Iterable of key names to look for in ``config``.
        value: Replacement value to assign to each matched key.

    Returns:
        The same ``config`` mapping with matching keys updated in-place.
    """
    for key in candidate_keys:
        if key in config:
            config[key] = value
    return config


class UniversalTokenModule(nn.Module):
    """SONIC-style action transform module (ATM) with FSQ token bottleneck.

    Implements the encoder → FSQ quantizer → decoder pipeline described in the
    SONIC paper.  Multiple named encoders (e.g. ``g1``, ``smpl``, ``teleop``)
    convert different flavors of tokenizer observations into a shared latent
    space.  An optional Finite Scalar Quantizer (FSQ) discretises the latent,
    producing a compact token representation.  One or more decoders then map
    the tokens (plus proprioception) back to joint-space actions.

    Token flow::

        tokenizer_obs ──► encoder(s) ──► [+ additive encoders]
                                      ──► [latent_residual (pre_quantization)]
                                      ──► FSQ quantizer
                                      ──► [+ latent_residual (post_quantization)]
                                      ──► decoder(s)
                                      ──► action_mean

    Latent residual modes allow an external HOI policy to inject corrections
    into the latent space without retraining the base ATM:

    * ``"post_quantization"`` - residual added to FSQ-quantized tokens (default).
    * ``"pre_quantization"`` - residual added *before* FSQ; the sum gets quantized.
    * ``"pre_quantization_replace"`` - latent is replaced entirely by the residual.

    Attributes:
        encoders: ``nn.ModuleDict`` of named encoder networks.
        quantizer: FSQ quantizer (``None`` when quantization is disabled).
        decoders: ``nn.ModuleDict`` of named decoder networks.
        aux_loss_func: ``nn.ModuleDict`` of auxiliary loss callables.
        token_dim: Dimensionality of a single token (equals ``num_fsq_levels``).
        max_num_tokens: Number of tokens produced per timestep.
        token_total_dim: ``token_dim * max_num_tokens`` - flat token size.
    """

    def __init__(
        self,
        env_config,
        algo_config,
        obs_dim_dict=None,
        module_dim_dict=None,
        proprioception_features=[],
        num_fsq_levels=5,
        fsq_level_list=16,
        max_num_tokens=None,
        down_t=2,
        num_future_frames=1,
        quantizer=None,
        encoders=None,
        decoders=None,
        aux_loss_func={},
        aux_loss_coef={},
        encoder_sample_probs=None,
        reencode_smpl_g1_recon=False,
        meta_action_dim=None,  # For hierarchical policies with split actions
        body_action_dim=None,  # For separate body decoder (e.g., 29 body joints)
        hand_action_dim=None,  # For separate hand decoder (e.g., 14 hand joints)
        freeze_encoders=False,
        freeze_decoders=False,
        freeze_quantizer=False,
        stiff_compliance_threshold=0.01,  # Threshold for stiff mode filtering
        optimize_encoders_ratio_for_CHIP=False,  # CHIP compliance training optimization
        active_encoders=None,  # Optional list of encoder names to activate (None = all)
        active_decoders=None,  # Optional list of decoder names to activate (None = all)
        **kwargs,  # noqa: ARG002
    ):
        """Initialise encoders, FSQ quantizer, decoders, and auxiliary losses.

        Args:
            env_config: Environment configuration object exposing
                ``obs.group_obs_dims``, ``obs.group_obs_names``, and
                ``robot.actions_dim``.
            algo_config: Algorithm configuration (stored but not directly
                accessed during construction).
            obs_dim_dict: Mapping from observation name to dimension.  Falls
                back to ``env_config.robot.algo_obs_dim_dict`` when ``None``.
            module_dim_dict: Optional extra dimension overrides for named
                intermediate features.
            proprioception_features: List of observation keys whose concatenation
                forms the proprioception input fed to every decoder.
            num_fsq_levels: Number of FSQ levels (equals ``token_dim``).
            fsq_level_list: Per-level codebook size.  An ``int`` is broadcast
                to ``[fsq_level_list] * num_fsq_levels``.
            max_num_tokens: Explicit token count per timestep.  When ``None``
                this is derived as ``max(1, num_future_frames // 2**down_t)``.
            down_t: Temporal downsampling factor for token count derivation.
            num_future_frames: Number of future motion frames in the tokenizer
                input window.
            quantizer: Hydra-instantiable config for the FSQ quantizer.
                ``None`` disables quantization (identity passthrough).
            encoders: Dict of encoder configs (Hydra DictConfig).  Each entry
                specifies ``inputs``, ``outputs``, ``params``, and optional
                ``additive_to`` / ``sub_encoders`` / ``mask`` / ``freeze``.
            decoders: Dict of decoder configs (Hydra DictConfig).  Each entry
                specifies ``inputs``, ``outputs``, ``conds``, ``params``, and
                ``has_temporal_dim``.
            aux_loss_func: Dict of auxiliary loss configs to instantiate as
                ``nn.Module`` callables (stored in ``self.aux_loss_func``).
            aux_loss_coef: Dict mapping loss name → scalar coefficient passed
                back to the trainer.
            encoder_sample_probs: Ordered dict mapping encoder name → sampling
                probability; defines the column order of ``encoder_index`` in
                tokenizer observations.
            reencode_smpl_g1_recon: When ``True``, re-encode the G1 kinematic
                decoder output to compute cycle-consistency auxiliary losses.
            meta_action_dim: Action dimensionality for hierarchical policies
                where the top-level action differs from the full joint count.
            body_action_dim: Dimensionality of body joints for split
                body / hand decoding (default 29).
            hand_action_dim: Dimensionality of hand joints for split
                body / hand decoding (default 14).
            freeze_encoders: Freeze all encoder parameters after init.
            freeze_decoders: Freeze all decoder parameters after init.
            freeze_quantizer: Freeze quantizer parameters after init.
            stiff_compliance_threshold: Absolute compliance value below which
                an environment is treated as "stiff" for auxiliary loss gating.
            optimize_encoders_ratio_for_CHIP: When ``True``, enforce one-hot
                encoder selection (CHIP training mode) instead of the default
                multi-hot selection where SMPL-native envs activate both SMPL
                and G1 encoders.
            active_encoders: Optional list of encoder names to instantiate and
                run.  All encoders are active when ``None``.
            active_decoders: Optional list of decoder names to run during
                forward.  All decoders are run when ``None``.
            **kwargs: Absorbed for forward-compatibility.
        """
        super().__init__()

        # Store freeze flags
        self.freeze_encoders = freeze_encoders
        self.freeze_decoders = freeze_decoders
        self.stiff_compliance_threshold = stiff_compliance_threshold
        self.freeze_quantizer = freeze_quantizer
        self.optimize_encoders_ratio_for_CHIP = optimize_encoders_ratio_for_CHIP

        if self.optimize_encoders_ratio_for_CHIP:
            logger.info(
                "[CHIP Mode] optimize_encoders_ratio_for_CHIP=True: "
                "Native encoder selection is now one-hot (no G1 auto-activation for SMPL). "
                "G1 latents for SMPL-native envs computed only in aux losses when compliance=0."
            )

        # Cache for last encoded tokens (for external access, e.g., by callbacks)
        # These are populated during forward() and can be read afterwards
        self._last_encoded_tokens = None  # dict[encoder_name -> Tensor]
        self._last_encoded_latents = None  # dict[encoder_name -> Tensor] (pre-quantization)

        self.env_config = env_config
        self.algo_config = algo_config
        self.encoders_cfg = encoders
        self.decoders_cfg = decoders
        self.encoder_sample_probs = encoder_sample_probs
        self.reencode_smpl_g1_recon = reencode_smpl_g1_recon
        self.tokenizer_obs_dims = self.env_config.obs.group_obs_dims["tokenizer"]
        self.tokenizer_obs_names = self.env_config.obs.group_obs_names["tokenizer"]
        # The tokenizer observation schema is fixed after module construction.
        tokenizer_obs_specs = []
        tokenizer_obs_offset = 0
        for name in self.tokenizer_obs_names:
            dims = tuple(self.tokenizer_obs_dims[name])
            flat_dim = int(np.prod(dims))
            tokenizer_obs_specs.append(
                (name, tokenizer_obs_offset, tokenizer_obs_offset + flat_dim, dims)
            )
            tokenizer_obs_offset += flat_dim
        self.tokenizer_obs_specs = tuple(tokenizer_obs_specs)
        self.tokenizer_obs_total_dim = tokenizer_obs_offset
        self.actions_dim = self.env_config.robot.actions_dim
        self.meta_action_dim = (
            meta_action_dim  # Can be different from actions_dim for hierarchical policies
        )

        if obs_dim_dict is None:
            obs_dim_dict = getattr(env_config.robot, "algo_obs_dim_dict", {})

        if module_dim_dict is None:
            module_dim_dict = {}

        self.obs_dim_dict = obs_dim_dict
        self.module_dim_dict = module_dim_dict
        self.proprioception_features = proprioception_features
        self.num_future_frames = num_future_frames

        # Initialize auxiliary loss functions (nn.ModuleDict so sub-module buffers
        # are part of the model state_dict and visible to DDP)
        self.aux_loss_func = nn.ModuleDict()
        for name, loss_func in aux_loss_func.items():
            self.aux_loss_func[name] = common.custom_instantiate(loss_func, _resolve=False)
        self.aux_loss_coef = aux_loss_coef

        module_input_candidate_params = ["input_dim"]

        module_output_candidate_params = ["output_dim"]

        """
        Initialize quantizer
        """
        if isinstance(fsq_level_list, int):
            fsq_level_list = [fsq_level_list] * num_fsq_levels
        if quantizer is not None:
            self.quantizer = common.custom_instantiate(
                quantizer, levels=fsq_level_list, _resolve=False
            )
        else:
            self.quantizer = None
        self.num_fsq_levels = num_fsq_levels
        self.fsq_level_list = fsq_level_list

        # quantizer levels determine the embedding dimension
        self.token_dim = self.num_fsq_levels
        self.down_t = down_t  # default
        if max_num_tokens is not None:
            self.max_num_tokens = max_num_tokens
        else:
            self.max_num_tokens = max(1, self.num_future_frames // (2**self.down_t))
        self.token_total_dim = self.token_dim * self.max_num_tokens
        logger.info(
            f"Motion Encoder and Quantizer initialized with embedding dim: {self.token_total_dim} (num_tokens={self.max_num_tokens}, token_dim={self.token_dim})"  # noqa: E501
        )

        """
        Initialize motion encoders dynamically
        """
        self.encoders = nn.ModuleDict()
        self.sub_encoders = {}
        self.encoder_input_features = {}
        self.encoder_mask_features = {}
        self.encoders_to_iterate = []
        self.additive_encoders = {}  # Map: base_encoder_name -> list of additive encoder names

        # First pass: identify additive encoders
        for encoder_name, encoder_config in self.encoders_cfg.items():
            additive_to = encoder_config.get("additive_to", None)
            if additive_to is not None:
                if additive_to not in self.additive_encoders:
                    self.additive_encoders[additive_to] = []
                self.additive_encoders[additive_to].append(encoder_name)

        # New config structure - initialize all encoders from config
        for encoder_name, encoder_config in self.encoders_cfg.items():
            # Skip non-active encoders early (avoids KeyError on missing obs dims)
            if active_encoders is not None and encoder_name not in active_encoders:
                continue

            sub_encoder_only = encoder_config.get("sub_encoder_only", False)
            is_additive = encoder_config.get("additive_to", None) is not None
            # Don't iterate additive encoders independently - they're called within their base encoder
            if not sub_encoder_only and not is_additive:
                self.encoders_to_iterate.append(encoder_name)
            self.sub_encoders[encoder_name] = encoder_config.get("sub_encoders", [])

            input_features = encoder_config.get("inputs", [])
            output_features = encoder_config.get("outputs", [])
            input_feature_dim = sum([self.tokenizer_obs_dims[key][-1] for key in input_features])
            if len(output_features) > 0:
                output_feature_dim = sum(
                    [self.tokenizer_obs_dims[key][-1] for key in output_features]
                )
            else:
                output_feature_dim = self.token_dim
            self.encoder_input_features[encoder_name] = input_features
            self.encoder_mask_features[encoder_name] = list(encoder_config.get("mask", []))

            if len(self.sub_encoders[encoder_name]) > 0:
                continue

            encoder_params = encoder_config["params"].copy()
            # Set dynamic parameters
            set_fuzzy_config_params(
                encoder_params, module_input_candidate_params, input_feature_dim
            )
            set_fuzzy_config_params(
                encoder_params, module_output_candidate_params, output_feature_dim
            )

            # Instantiate encoder
            encoder = common.custom_instantiate(encoder_params, _resolve=False)
            self.encoders[encoder_name] = encoder

            # Per-encoder freeze support
            if encoder_config.get("freeze", False):
                for param in encoder.parameters():
                    param.requires_grad = False
                logger.info(f"Froze encoder: {encoder_name}")

            logger.info(f"Initialized {encoder_name} encoder with input features: {input_features}")

        # Log additive encoder relationships
        if self.additive_encoders:
            for base_encoder, additive_list in self.additive_encoders.items():
                logger.info(
                    f"Additive encoders for '{base_encoder}': {additive_list} (outputs will be summed)"
                )

        """
        Initialize motion decoders dynamically
        """
        self.decoders = nn.ModuleDict()
        self.decoder_input_features = {}
        self.decoder_output_features = {}
        self.decoder_output_feature_dims = {}
        self.decoder_cond_features = {}  # For root-disentangled decoders (external_cond)
        self.decoder_mask_features = {}

        # Support custom meta_action_dim for hierarchical policies
        meta_action_dim = getattr(self, "meta_action_dim", None) or self.actions_dim

        # Compute proprioception dim from actual features (not hardcoded actor_obs)
        proprioception_dim = sum(
            self.obs_dim_dict[key]
            for key in self.proprioception_features
            if key in self.obs_dim_dict
        ) or self.obs_dim_dict.get("actor_obs", 0)

        decoder_feature_dims_map = {
            "proprioception": proprioception_dim,
            "token": self.token_dim,
            "token_flattened": self.token_dim * self.max_num_tokens,
            "action": self.actions_dim,
            "meta_action": meta_action_dim,  # For hierarchical policies
            "hand_action": hand_action_dim or 14,  # 14 hand joints default
            "body_action": body_action_dim or 29,  # 29 body joints default
        }
        for k, v in self.tokenizer_obs_dims.items():
            if k not in decoder_feature_dims_map:
                decoder_feature_dims_map[k] = v[-1]
        self.decoder_feature_dims_map = decoder_feature_dims_map

        for decoder_name, decoder_config in self.decoders_cfg.items():
            # Skip non-active decoders early (avoids KeyError on missing obs dims)
            if active_decoders is not None and decoder_name not in active_decoders:
                continue

            decoder_params = decoder_config["params"].copy()
            input_features = decoder_config.get("inputs", [])
            output_features = decoder_config.get("outputs", [])
            cond_features = decoder_config.get("conds", [])
            has_temporal_dim = decoder_config.has_temporal_dim
            input_feature_dim = 0
            for key in input_features:
                input_feature_dim += self.decoder_feature_dims_map[key]
            output_feature_dim = 0
            self.decoder_output_feature_dims[decoder_name] = {}
            for key in output_features:
                if key in decoder_feature_dims_map:
                    feature_dim = decoder_feature_dims_map[key]
                else:
                    assert has_temporal_dim
                    feature_dim = self.tokenizer_obs_dims[key][-1]
                self.decoder_output_feature_dims[decoder_name][key] = feature_dim
                output_feature_dim += feature_dim
            set_fuzzy_config_params(
                decoder_params, module_input_candidate_params, input_feature_dim
            )
            set_fuzzy_config_params(
                decoder_params, module_output_candidate_params, output_feature_dim
            )

            # For decoders with conds: compute external_cond_dim from cond feature dimensions.
            if cond_features:
                external_cond_dim = sum(self.tokenizer_obs_dims[key][-1] for key in cond_features)
                decoder_params["external_cond_dim"] = external_cond_dim
                logger.info(
                    f"Decoder '{decoder_name}' has conds={cond_features} "
                    f"with external_cond_dim={external_cond_dim}"
                )
            self.decoder_cond_features[decoder_name] = cond_features
            self.decoder_mask_features[decoder_name] = list(decoder_config.get("mask", []))

            # Instantiate decoder
            decoder = common.custom_instantiate(decoder_params, _resolve=False)
            self.decoders[decoder_name] = decoder
            self.decoder_input_features[decoder_name] = input_features
            self.decoder_output_features[decoder_name] = output_features

            logger.info(
                f"Initialized {decoder_name} decoder with input features: {input_features} and output features: {output_features}"  # noqa: E501
            )

        # Filter active encoders/decoders if specified (for kinematic-only training)
        if active_encoders is not None:
            self.encoders_to_iterate = [e for e in self.encoders_to_iterate if e in active_encoders]
            logger.info(f"Active encoders filtered to: {self.encoders_to_iterate}")
        if active_decoders is not None:
            # Keep all decoders in ModuleDict (for checkpoint compat), but only iterate active ones
            self._active_decoders = set(active_decoders)
            logger.info(f"Active decoders filtered to: {list(self._active_decoders)}")
        else:
            self._active_decoders = None

        # Apply freeze logic
        if self.freeze_encoders:
            for encoder in self.encoders.values():
                for param in encoder.parameters():
                    param.requires_grad = False
            logger.info(f"Froze encoders: {list(self.encoders.keys())}")

        if self.freeze_decoders:
            for decoder in self.decoders.values():
                for param in decoder.parameters():
                    param.requires_grad = False
            logger.info(f"Froze decoders: {list(self.decoders.keys())}")

        if self.freeze_quantizer and self.quantizer is not None:
            for param in self.quantizer.parameters():
                param.requires_grad = False
            logger.info("Froze quantizer")

        # Variable frame support: enabled when any encoder or decoder has mask observations
        self.variable_frames_enabled = any(
            feats
            for feats in (
                *self.encoder_mask_features.values(),
                *self.decoder_mask_features.values(),
            )
        )
        if self.variable_frames_enabled:
            # Cache frame indices for mask creation (avoids allocation every forward)
            self.register_buffer(
                "_frame_indices",
                torch.arange(self.num_future_frames).unsqueeze(0),
                persistent=False,
            )

    def _create_frame_and_token_masks(self, tokenizer_obs):
        """Create frame and token masks from num_frames observation.

        Returns (frame_mask, token_mask) or (None, None) if disabled.
            frame_mask: [B*seq, max_frames] bool, True=valid
            token_mask: [B*seq, max_tokens] bool, True=valid
        """
        if "command_num_frames" not in tokenizer_obs:
            return None, None

        num_frames = tokenizer_obs["command_num_frames"]  # [B, seq, 1]
        num_frames_flat = num_frames.reshape(-1, 1)  # [B*seq, 1]
        frame_mask = self._frame_indices < num_frames_flat  # [B*seq, max_frames]

        frames_per_token = 2**self.down_t
        token_frame_mask = frame_mask.reshape(-1, self.max_num_tokens, frames_per_token)
        token_mask = token_frame_mask.all(dim=-1)  # [B*seq, max_tokens]

        return frame_mask, token_mask

    def parse_tokenizer_obs(self, input_data):
        """Split the flat tokenizer observation tensor into a named dict.

        The tokenizer observation is stored as a single concatenated vector in
        ``input_data["tokenizer"]``.  This method reshapes each slice back to
        its original multi-dimensional form using the dimension metadata from
        ``env_config``.

        Args:
            input_data: Dict containing ``"tokenizer"`` key with shape
                ``(..., total_tokenizer_dim)``.

        Returns:
            Dict mapping observation name to tensor with shape
            ``(*batch_dims, *obs_dims)`` for each registered tokenizer
            observation.
        """
        tokenizer_obs = input_data["tokenizer"]
        tokenizer_obs_dict = {}
        for name, start, end, dims in self.tokenizer_obs_specs:
            tokenizer_obs_dict[name] = tokenizer_obs[..., start:end].reshape(
                tokenizer_obs.shape[:-1] + dims
            )
        assert self.tokenizer_obs_total_dim == tokenizer_obs.shape[-1], (
            f"{self.tokenizer_obs_total_dim=}, {tokenizer_obs.shape[-1]=}"
        )
        return tokenizer_obs_dict

    def create_encoder_masks(self, tokenizer_obs):
        """Create encoder masks for each encoder.

        When optimize_encoders_ratio_for_CHIP=False (legacy):
            - encoder_index is multi-hot: SMPL-native envs have both SMPL=1 and G1=1
            - encoder_masks["g1"] includes G1-native AND SMPL-native envs
            - encoder_masks["g1_has_smpl"] identifies which G1-masked envs are SMPL-native

        When optimize_encoders_ratio_for_CHIP=True (CHIP mode):
            - encoder_index is one-hot: each env has exactly one native encoder
            - encoder_masks are disjoint (no overlap)
            - encoder_masks["g1_has_smpl"] is empty (G1-native envs don't have SMPL)
            - G1 latents for SMPL-native envs are computed separately in aux losses
        """
        if len(self.encoders) == 1:
            return {list(self.encoders.keys())[0]: None}

        encoder_masks = {}
        encoder_index = tokenizer_obs["encoder_index"]

        for i, encoder_name in enumerate(self.encoder_sample_probs.keys()):
            encoder_masks[encoder_name] = encoder_index[..., i].bool().flatten()

        # Re-organized creation of intersection encoder masks.
        # NOTE: No need to use compliance encoders in this version -- directly use the normal encoders

        # For encoder pairs, create combined masks reflecting shared samples.
        # The pairs and their intersection masks:
        encoder_mask_combinations = [
            # (key1, key2, intersection_mask_names)
            ("g1", "smpl", [("g1_has_smpl", "smpl", "g1")]),
            (
                "teleop",
                "smpl",
                [("teleop_has_smpl", "smpl", "teleop"), ("smpl_has_teleop", "teleop", "smpl")],
            ),
            ("g1", "teleop", [("g1_has_teleop", "teleop", "g1")]),
            ("teleop", "g1", [("teleop_has_g1", "g1", "teleop")]),
            ("g1", "soma", [("g1_has_soma", "soma", "g1")]),
        ]
        for key1, key2, mask_defs in encoder_mask_combinations:
            if key1 in encoder_masks and key2 in encoder_masks:
                for mask_name, mask_src, mask_cond in mask_defs:
                    encoder_masks[mask_name] = encoder_masks[mask_src][encoder_masks[mask_cond]]
        return encoder_masks

    def assemble_all_tokens(self, encoded_tokens, encoder_masks, batch_size, seq_len):
        """Scatter per-encoder tokens into a single batch-aligned tensor.

        Each encoder processes only the environments assigned to it (via
        ``encoder_masks``).  This method writes each encoder's output back to
        the correct rows of a zero-initialised buffer, then reshapes to
        ``(batch, seq, num_tokens, token_dim)``.

        Args:
            encoded_tokens: Dict mapping encoder name to tensor of shape
                ``(num_masked, num_tokens, token_dim)``.
            encoder_masks: Dict mapping encoder name to a boolean index tensor
                of length ``batch*seq``.  ``None`` means all samples.
            batch_size: Batch dimension ``B``.
            seq_len: Sequence dimension ``S``.

        Returns:
            Tensor of shape ``(B, S, num_tokens, token_dim)`` with each row
            filled by its assigned encoder's output.
        """
        first_token = encoded_tokens[list(encoded_tokens.keys())[0]]
        if len(encoded_tokens) == 1:
            return first_token.view(batch_size, seq_len, *first_token.shape[1:])

        all_tokens = torch.zeros(
            (batch_size * seq_len,) + first_token.shape[1:],
            dtype=first_token.dtype,
            device=first_token.device,
        )
        for encoder_name in encoded_tokens.keys():
            all_tokens[encoder_masks[encoder_name]] = encoded_tokens[encoder_name]
        all_tokens = all_tokens.view(batch_size, seq_len, *all_tokens.shape[1:])
        return all_tokens

    def _encode_single(self, encoder_name, tokenizer_obs, encoder_mask=None, frame_mask=None):
        """Encode using a single encoder without quantization or additive composition.
        This is the core encoding logic used by both regular and additive encoders.

        Args:
            encoder_name: Name of the encoder to use
            tokenizer_obs: Dictionary of tokenizer observations
            encoder_mask: Optional mask for selecting specific samples
            frame_mask: Optional [B*seq, max_frames] bool mask for variable frame support

        Returns:
            latent: The encoded latent representation
        """  # noqa: D205
        encoder = sub_encoders = None
        if encoder_name in self.encoders:
            encoder = self.encoders[encoder_name]
        else:
            sub_encoders = [
                self.encoders[sub_encoder_name]
                for sub_encoder_name in self.sub_encoders[encoder_name]
            ]

        input_features = self.encoder_input_features[encoder_name]

        obs_list = [tokenizer_obs[key] for key in input_features]
        # Only handle dimension broadcasting for the "smpl" encoder_name and for obs with last dim 9 or 12
        if "smpl" in encoder_name:
            max_ndim = max(obs.ndim for obs in obs_list)
            # Check if any obs needs broadcasting: (last dim is 9 or 12 and ndim < max_ndim)
            need_broadcast = any(
                (obs.shape[-1] in (9, 12) and obs.ndim < max_ndim) for obs in obs_list
            )
            if need_broadcast:
                aligned_obs_list = []
                # Use the first obs of max_ndim as the temporal reference
                target_obs = next(o for o in obs_list if o.ndim == max_ndim)
                temporal_dim = target_obs.shape[-2]
                for obs in obs_list:
                    if obs.shape[-1] in (9, 12) and obs.ndim < max_ndim:
                        # Add missing dimension(s)
                        while obs.ndim < max_ndim:
                            obs = obs.unsqueeze(-2)  # noqa: PLW2901
                        # Expand temporal dimension
                        expand_shape = list(obs.shape)
                        expand_shape[-2] = temporal_dim
                        obs = obs.expand(*expand_shape)  # noqa: PLW2901
                    aligned_obs_list.append(obs)
                encoder_input = torch.cat(aligned_obs_list, dim=-1)
            else:
                encoder_input = torch.cat(obs_list, dim=-1)
        else:
            encoder_input = torch.cat(obs_list, dim=-1)
        encoder_input = encoder_input.view(-1, *encoder_input.shape[2:])

        # Apply encoder_mask to both input and frame_mask
        frame_mask_enc = None
        if encoder_mask is not None:
            encoder_input = encoder_input[encoder_mask]
            if frame_mask is not None:
                frame_mask_enc = frame_mask[encoder_mask]
        elif frame_mask is not None:
            frame_mask_enc = frame_mask

        # encode using the provided encoder (with gradients enabled for end-to-end training)
        if encoder is not None:
            if frame_mask_enc is not None and self.encoder_mask_features.get(encoder_name):
                latent = encoder(encoder_input, frame_mask=frame_mask_enc)
            else:
                latent = encoder(encoder_input)
        else:
            latent = encoder_input
            for sub_encoder in sub_encoders:
                latent = sub_encoder(latent)

        return latent

    def encode(
        self, encoder_name, tokenizer_obs, encoder_mask=None, no_quantization=False, frame_mask=None
    ):
        """Encode using the specified encoder, including any additive encoders.

        Args:
            encoder_name: Name of the base encoder to use
            tokenizer_obs: Dictionary of tokenizer observations
            encoder_mask: Optional mask for selecting specific samples
            no_quantization: If True, skip quantization and return raw latent
            frame_mask: Optional [B*seq, max_frames] bool mask for variable frame support

        Returns:
            If no_quantization: latent tensor
            Otherwise: (encoded_tokens, latent) tuple
        """
        # Get base encoder latent
        latent = self._encode_single(
            encoder_name, tokenizer_obs, encoder_mask, frame_mask=frame_mask
        )

        # Add contributions from additive encoders
        if encoder_name in self.additive_encoders:
            for additive_encoder_name in self.additive_encoders[encoder_name]:
                additive_latent = self._encode_single(
                    additive_encoder_name, tokenizer_obs, encoder_mask, frame_mask=frame_mask
                )
                latent = latent + additive_latent

        if no_quantization:
            return latent

        # quantize using quantizer
        if self.quantizer is not None:
            quantized_codes, _ = self.quantizer(latent)
            encoded_tokens = quantized_codes.contiguous()
        else:
            encoded_tokens = latent
        return encoded_tokens, latent

    def decode(self, decoder_name, decode_input_dict, token_mask=None):
        """Run a single named decoder and split its output by feature.

        Concatenates the decoder's declared input features from
        ``decode_input_dict``, passes them through the decoder network
        (optionally supplying ``external_cond`` and ``token_mask``), then
        slices the output back into a per-feature dict.

        Args:
            decoder_name: Key into ``self.decoders`` and associated metadata.
            decode_input_dict: Dict containing at least the keys declared in
                the decoder's ``inputs`` and ``conds`` config entries.
                Common keys include ``"token"``, ``"token_flattened"``, and
                ``"proprioception"``.
            token_mask: Optional ``(B*seq, max_tokens)`` bool mask for
                variable-length token sequences.  Only forwarded to decoders
                that declare mask features.

        Returns:
            Dict mapping output feature name to the corresponding slice of the
            decoder output tensor, e.g.
            ``{"action": Tensor(..., action_dim)}``.
        """
        decoder = self.decoders[decoder_name]
        input_features = self.decoder_input_features[decoder_name]
        output_feature_dims = self.decoder_output_feature_dims[decoder_name]
        cond_features = self.decoder_cond_features.get(decoder_name, [])
        decoder_input = torch.cat([decode_input_dict[key] for key in input_features], dim=-1)

        # Build optional kwargs for the decoder call
        kwargs = {}
        if cond_features:
            kwargs["external_cond"] = torch.cat(
                [decode_input_dict[key] for key in cond_features], dim=-1
            )
        if token_mask is not None and self.decoder_mask_features.get(decoder_name):
            kwargs["token_mask"] = token_mask
        output = decoder(decoder_input, **kwargs)

        # parse output
        output_dict = {}
        index = 0
        for key, dim in output_feature_dims.items():
            output_dict[key] = output[..., index : index + dim]
            index += dim
        assert index == output.shape[-1], f"{index=}, {output.shape[-1]=}"

        return output_dict

    def forward(  # noqa: D417
        self,
        input_data,
        compute_aux_loss=False,
        return_dict=False,
        latent_residual=None,
        latent_residual_mode="post_quantization",
        **kwargs,  # noqa: ARG002
    ):
        """Run the full encode → quantize → decode pipeline.

        Parses tokenizer observations, routes each environment to its assigned
        encoder, optionally applies an external latent residual, then decodes
        to joint-space actions.  When ``compute_aux_loss=True``, also computes
        all registered auxiliary losses (e.g. G1-SMPL alignment, cycle
        consistency) and returns a rich result dict.

        Args:
            input_data: Dict of named observation tensors, all with leading
                shape ``(B, S, ...)``.  Must contain at minimum ``"actor_obs"``
                (for batch/seq inference) and ``"tokenizer"`` (flat tokenizer
                obs of shape ``(B, S, total_tokenizer_dim)``).
            compute_aux_loss: When ``True``, evaluate all auxiliary loss
                functions and include them in the returned dict.
            return_dict: When ``True`` and ``compute_aux_loss=False``, return
                the full output dict instead of just ``action_mean``.
            latent_residual: Optional additive correction in latent token
                space.  Shape ``(B, token_total_dim)`` where
                ``token_total_dim = max_num_tokens * token_dim``.  Allows HOI
                policies to steer motion without modifying the base ATM.
            latent_residual_mode: Controls *when* ``latent_residual`` is
                applied:

                * ``"post_quantization"`` - add after FSQ (default, residual
                  stays continuous).
                * ``"pre_quantization"`` - add before FSQ (residual gets
                  quantized together with the encoder latent).
                * ``"pre_quantization_replace"`` - replace the encoder latent
                  entirely with ``latent_residual`` before quantization.
            **kwargs: Passed through; currently unused.

        Returns:
            When ``compute_aux_loss=True`` or ``return_dict=True``: a dict
            with keys:

            * ``"action_mean"`` - joint targets, shape ``(B, S, action_dim)``.
            * ``"aux_losses"`` - dict of scalar loss tensors (empty when
              ``compute_aux_loss=False``).
            * ``"aux_loss_coef"`` - per-loss coefficient dict from config.
            * ``"decoded_outputs"`` - raw decoder output dicts keyed by
              decoder name.
            * ``"tokenizer_obs"`` - parsed tokenizer observation dict.
            * ``"encoder_masks"`` - per-encoder boolean index tensors.
            * ``"encoded_tokens"`` - post-quantization tokens per encoder.
            * ``"encoded_latents"`` - pre-quantization latents per encoder.
            * ``"encoders_cfg"`` / ``"decoders_cfg"`` - config references.

            When ``compute_aux_loss=False`` and ``return_dict=False``:
            ``action_mean`` tensor directly.
        """
        # parse tokenizer obs
        batch_size, seq_len = input_data["actor_obs"].shape[:2]
        tokenizer_obs = self.parse_tokenizer_obs(input_data)
        proprioception_input = torch.cat(
            [input_data[key] for key in self.proprioception_features], dim=-1
        )

        # Reshape residual if provided: (batch, token_total_dim) -> (batch, 1, max_num_tokens, token_dim)
        residual_reshaped = None
        if latent_residual is not None:
            residual_reshaped = latent_residual.view(
                batch_size, 1, self.max_num_tokens, self.token_dim
            )

        # Variable frame masks
        frame_mask, token_mask = self._create_frame_and_token_masks(tokenizer_obs)

        # encode motion using all available encoders
        encoder_masks = self.create_encoder_masks(tokenizer_obs)
        encoded_tokens = {}
        encoded_latents = {}
        if latent_residual is not None and latent_residual_mode in [
            "pre_quantization",
            "pre_quantization_replace",
        ]:
            # PRE-QUANTIZATION MODES: add or replace residual before FSQ
            # Reshape residual to (batch*seq, num_tokens, token_dim) for masking
            residual_flat = latent_residual.view(
                batch_size * seq_len, self.max_num_tokens, self.token_dim
            )

            for encoder_name in self.encoders_to_iterate:
                encoder_mask = encoder_masks[encoder_name]

                # Get raw latent (including additive encoders) without quantization
                latent = self.encode(
                    encoder_name,
                    tokenizer_obs,
                    encoder_mask,
                    no_quantization=True,
                    frame_mask=frame_mask,
                )
                # Apply same mask to residual before adding
                if encoder_mask is not None:
                    masked_residual = residual_flat[encoder_mask]
                else:
                    masked_residual = residual_flat

                # Apply residual before quantization (only if we have samples)
                if latent.shape[0] > 0:
                    if latent_residual_mode == "pre_quantization":
                        # Add residual to encoder latent
                        latent = latent + masked_residual
                    elif latent_residual_mode == "pre_quantization_replace":
                        # Replace encoder latent with residual (zero out encoder)
                        latent = masked_residual
                    else:
                        raise ValueError(f"Unknown latent_residual_mode: {latent_residual_mode}")

                # Now quantize
                if self.quantizer is not None:
                    quantized_codes, _ = self.quantizer(latent)
                    encoded_tokens[encoder_name] = quantized_codes.contiguous()
                else:
                    encoded_tokens[encoder_name] = latent
                encoded_latents[encoder_name] = latent
        else:
            # STANDARD MODE: encode normally
            for encoder_name in self.encoders_to_iterate:
                encoded_tokens[encoder_name], encoded_latents[encoder_name] = self.encode(
                    encoder_name,
                    tokenizer_obs,
                    encoder_masks[encoder_name],
                    frame_mask=frame_mask,
                )
        all_tokens = self.assemble_all_tokens(encoded_tokens, encoder_masks, batch_size, seq_len)

        # POST-QUANTIZATION MODE: add residual after FSQ tokens (default)
        if latent_residual is not None and latent_residual_mode == "post_quantization":
            all_tokens = all_tokens + residual_reshaped

        # Cache tokens for external access (e.g., by callbacks)
        self._last_encoded_tokens = {k: v.detach().cpu() for k, v in encoded_tokens.items()}
        self._last_encoded_latents = {k: v.detach().cpu() for k, v in encoded_latents.items()}

        # Cache flattened full latent on device for reward computation (token smoothness)
        # all_tokens is the post-quantization token that gets sent to decoder
        # Shape: (batch, seq, num_tokens, token_dim) -> (batch, seq, latent_dim)
        self._last_full_latent_flat = all_tokens.detach().view(*all_tokens.shape[:-2], -1)

        # decode action and motion
        decode_input_dict = {
            "token": all_tokens,
            "token_flattened": all_tokens.view(*all_tokens.shape[:-2], -1),
            "proprioception": proprioception_input,
        }
        decode_input_dict.update(tokenizer_obs)

        decoded_outputs = {}
        decoders_to_run = (
            self._active_decoders if self._active_decoders is not None else self.decoders.keys()
        )
        for decoder_name in decoders_to_run:
            decoded_outputs[decoder_name] = self.decode(
                decoder_name, decode_input_dict, token_mask=token_mask
            )

        # Support "body_action", "meta_action", and "action" outputs (g1_dyn may not exist in kinematic-only mode)
        if "g1_dyn" in decoded_outputs:
            g1_dyn_out = decoded_outputs["g1_dyn"]
            if "body_action" in g1_dyn_out:
                action_mean = g1_dyn_out["body_action"]
            elif "meta_action" in g1_dyn_out:
                action_mean = g1_dyn_out["meta_action"]
            else:
                action_mean = g1_dyn_out["action"]

            # Concatenate hand decoder output if present
            if "hand_dyn" in decoded_outputs and "hand_action" in decoded_outputs["hand_dyn"]:
                hand_action = decoded_outputs["hand_dyn"]["hand_action"]
                action_mean = torch.cat([action_mean, hand_action], dim=-1)
        else:
            action_mean = None

        # compute aux losses
        if compute_aux_loss:
            aux_losses = {}

            # Initialize all paired latents
            reencoded_smpl_g1_latents = None
            paired_g1_smpl_latents = None
            paired_compliance_latents = None
            original_g1_latents_for_reencode = None

            # Determine encoder names
            smpl_encoder_name = "smpl" if "smpl" in self.encoders_to_iterate else None
            teleop_encoder_name = "teleop" if "teleop" in self.encoders_to_iterate else None

            # =========================================================================
            # STIFF-MODE OPTIMIZATION: Check for stiff samples FIRST before computing
            # expensive G1 latents. G1-SMPL loss and cycle consistency loss ONLY apply
            # in stiff mode (compliance ≈ 0). Skip computation if all samples are compliant.
            # =========================================================================
            has_stiff_samples = False
            compliance_values = None
            smpl_latents = None
            smpl_mask = None

            if smpl_encoder_name is not None and "g1" in encoded_latents:
                smpl_mask = encoder_masks.get(smpl_encoder_name)

                if smpl_mask is not None and smpl_mask.sum() > 0:
                    smpl_latents = encoded_latents[smpl_encoder_name]

                    # Extract compliance values for these envs FIRST
                    if "compliance" in tokenizer_obs:
                        compliance_flat = tokenizer_obs["compliance"].view(
                            -1, tokenizer_obs["compliance"].shape[-1]
                        )
                        compliance_values = compliance_flat[smpl_mask]

                        # Check if ANY samples are stiff
                        is_stiff = (compliance_values.abs() < self.stiff_compliance_threshold).all(
                            dim=-1
                        )
                        has_stiff_samples = is_stiff.any().item()
                    else:
                        # No compliance info means all samples are "stiff" (default behavior)
                        has_stiff_samples = True

            # Only compute stiff-mode losses if there are stiff samples
            if has_stiff_samples and smpl_mask is not None:
                # Compute G1 latents for the same envs as SMPL (for proper pairing)
                # OPTIMIZATION: Detach here since all downstream losses use g1 as
                # fixed target (detach_g1_target=True). This avoids redundant gradient
                # computation through the g1 encoder for these latents.
                g1_latents_for_smpl = self.encode(
                    encoder_name="g1",
                    tokenizer_obs=tokenizer_obs,
                    encoder_mask=smpl_mask,
                    no_quantization=True,
                ).detach()

                paired_g1_smpl_latents = {
                    "g1": g1_latents_for_smpl,
                    "smpl": smpl_latents,
                    "compliance": compliance_values,
                }

                # Store original G1 latents for cycle consistency loss (already detached)
                original_g1_latents_for_reencode = g1_latents_for_smpl

                # Cycle consistency: re-encode decoded G1 motion (only if stiff samples exist)
                if self.reencode_smpl_g1_recon:
                    reencoded_smpl_g1_latents = self.encode(
                        encoder_name="g1",
                        tokenizer_obs=decoded_outputs["g1_kin"],
                        encoder_mask=smpl_mask,
                        no_quantization=True,
                    )

            # Compute paired teleop-SMPL latents for TeleopSmplComplianceLatentLoss
            # NOTE: This applies to ALL compliance values (not just stiff), so no stiff check
            if (
                teleop_encoder_name is not None
                and smpl_latents is not None
                and smpl_mask is not None
            ):
                # Compute teleop latents for the same envs as SMPL
                # OPTIMIZATION: Detach here since TeleopSmplComplianceLatentLoss uses
                # teleop as teacher (detach_teleop_target=True). Only SMPL learns.
                teleop_latents_for_smpl = self.encode(
                    encoder_name=teleop_encoder_name,
                    tokenizer_obs=tokenizer_obs,
                    encoder_mask=smpl_mask,
                    no_quantization=True,
                ).detach()

                paired_compliance_latents = {
                    "teleop": teleop_latents_for_smpl,
                    "smpl": smpl_latents,
                }

            loss_inputs = {
                "input_data": input_data,
                "tokenizer_obs": tokenizer_obs,
                "encoded_tokens": encoded_tokens,
                "encoded_latents": encoded_latents,
                "encoder_masks": encoder_masks,
                "decoded_outputs": decoded_outputs,
                "action_mean": action_mean,
                "encoders_cfg": self.encoders_cfg,
                "frame_mask": (
                    frame_mask.view(batch_size, seq_len, -1) if frame_mask is not None else None
                ),
                "token_mask": (
                    token_mask.view(batch_size, seq_len, -1) if token_mask is not None else None
                ),
                "decoders_cfg": self.decoders_cfg,
                "reencoded_smpl_g1_latents": reencoded_smpl_g1_latents,
                # New fields for compliance-aware losses
                "paired_g1_smpl_latents": paired_g1_smpl_latents,
                "paired_compliance_latents": paired_compliance_latents,
                "original_g1_latents_for_reencode": original_g1_latents_for_reencode,
            }

            for loss_name, loss_func in self.aux_loss_func.items():
                aux_losses[loss_name] = loss_func(loss_inputs)

            output = {
                "action_mean": action_mean,
                "aux_losses": aux_losses,
                "aux_loss_coef": self.aux_loss_coef,
                # Exposed for recon trainer (existing RL callers ignore these keys)
                "decoded_outputs": decoded_outputs,
                "tokenizer_obs": tokenizer_obs,
                "encoder_masks": encoder_masks,
                "encoded_tokens": encoded_tokens,
                "encoded_latents": encoded_latents,
                "encoders_cfg": self.encoders_cfg,
                "decoders_cfg": self.decoders_cfg,
            }
        elif return_dict:
            output = {
                "action_mean": action_mean,
                "aux_losses": {},
                "aux_loss_coef": self.aux_loss_coef,
                "decoded_outputs": decoded_outputs,
                "tokenizer_obs": tokenizer_obs,
                "encoder_masks": encoder_masks,
                "encoded_tokens": encoded_tokens,
                "encoded_latents": encoded_latents,
                "encoders_cfg": self.encoders_cfg,
                "decoders_cfg": self.decoders_cfg,
            }
        else:
            output = action_mean
        return output

    def get_token_info(self):
        """Return a summary of the FSQ token configuration.

        Returns:
            Dict with keys:

            * ``"token_dim"`` - dimensionality of one token.
            * ``"total_dim"`` - ``token_dim * max_num_tokens``.
            * ``"num_levels"`` - number of FSQ levels.
            * ``"level_list"`` - per-level codebook sizes, or ``None`` if the
              quantizer does not expose a ``levels`` attribute.
            * ``"model_available"`` - always ``True``.
        """
        return {
            "token_dim": self.token_dim,
            "total_dim": self.token_total_dim,
            "num_levels": self.num_fsq_levels,
            "level_list": (
                list(self.quantizer.levels) if hasattr(self.quantizer, "levels") else None
            ),
            "model_available": True,
        }

    def forward_with_external_tokens(  # noqa: D417
        self, input_data: dict, external_tokens: torch.Tensor, **kwargs  # noqa: ARG002
    ) -> torch.Tensor:
        """Forward pass with externally provided tokens (bypasses encoder).

        This is used when an external model (e.g., kinematic diffusion) provides
        pre-computed FSQ tokens, allowing the encoder to be bypassed while still
        using the decoder for action generation.

        Args:
            input_data: Dict with 'actor_obs' for proprioception
            external_tokens: Pre-computed FSQ tokens from kinematic diffusion
                            Shape: (B, 2, 32) or (B, seq, 2, 32)

        Returns:
            action_mean: (B, action_dim) or (B, seq, action_dim)
        """
        # Get proprioception input
        proprioception_input = torch.cat(
            [input_data[key] for key in self.proprioception_features], dim=-1
        )

        # Handle different input shapes
        if external_tokens.dim() == 3:
            # (B, 2, 32) -> add seq dim -> (B, 1, 2, 32)
            external_tokens = external_tokens.unsqueeze(1)

        # external_tokens: (B, seq, 2, 32) or (B, seq, num_tokens, token_dim)
        batch_size = external_tokens.shape[0]
        seq_len = external_tokens.shape[1]

        # Flatten tokens for decoder: (B, seq, 2, 32) -> (B, seq, 64)
        token_flattened = external_tokens.view(batch_size, seq_len, -1)

        # Build decode input dict
        decode_input_dict = {
            "token": external_tokens,
            "token_flattened": token_flattened,
            "proprioception": proprioception_input,
        }

        # Decode actions using g1_dyn decoder
        g1_dyn_out = self.decode("g1_dyn", decode_input_dict)
        if "body_action" in g1_dyn_out:
            action_mean = g1_dyn_out["body_action"]
        elif "meta_action" in g1_dyn_out:
            action_mean = g1_dyn_out["meta_action"]
        else:
            action_mean = g1_dyn_out["action"]

        # Concatenate hand decoder output if present
        if "hand_dyn" in self.decoders:
            hand_dyn_out = self.decode("hand_dyn", decode_input_dict)
            if "hand_action" in hand_dyn_out:
                action_mean = torch.cat([action_mean, hand_dyn_out["hand_action"]], dim=-1)

        # Squeeze seq dim if it was added
        if action_mean.shape[1] == 1:
            action_mean = action_mean.squeeze(1)

        return action_mean

    def get_example_input(self, encoder_name, batch_size=1, device="cpu"):
        """Generate example input for ONNX export with specific encoder.

        Args:
            encoder_name: Name of the encoder to use
            batch_size: Batch size for the example input
            device: Device to create tensors on

        Returns:
            Tensor with shape (batch_size, feature_dim) including encoder features and proprioception
        """
        if encoder_name not in self.encoders:
            raise ValueError(
                f"Encoder '{encoder_name}' not found. Available encoders: {list(self.encoders.keys())}"
            )

        # Calculate total input feature dimension for the specified encoder
        encoder_input_features = self.encoder_input_features[encoder_name]
        total_feature_dim = 0

        for feature_name in encoder_input_features:
            if feature_name in self.tokenizer_obs_dims:
                feature_dims = self.tokenizer_obs_dims[feature_name]
                total_feature_dim += torch.prod(torch.tensor(feature_dims)).item()

        # Add proprioception dimension
        proprioception_dim = self.obs_dim_dict.get("actor_obs", 0)
        total_feature_dim += proprioception_dim

        # Create a single 2D tensor (B, F) including both encoder features and proprioception
        example_input = torch.randn(batch_size, total_feature_dim, device=device)

        return example_input

    def get_all_example_input(self, batch_size=1, device="cpu"):
        """Generate example inputs covering all tokenizer observations.

        Constructs random tensors whose shapes match the full tokenizer
        observation space plus proprioception.  Intended for ONNX tracing
        or shape debugging.

        Args:
            batch_size: Number of examples in the batch dimension.
            device: Target device for the returned tensors (e.g. ``"cpu"``
                or ``"cuda"``).

        Returns:
            Tuple of:

            * ``example_input`` - flat tensor of shape
              ``(batch_size, total_feature_dim)`` where
              ``total_feature_dim = tokenizer_feature_dim + proprioception_dim``.
            * ``example_dict`` - dict with keys ``"tokenizer"`` and
              ``"proprioception"``, each a random tensor with the
              corresponding shape.
        """
        # Calculate total input feature dimension for the specified encoder
        total_feature_dim = 0
        for feature_name in self.tokenizer_obs_names:
            feature_dims = self.tokenizer_obs_dims[feature_name]
            print(  # noqa: T201
                f"{feature_name}: {feature_dims}, start: {total_feature_dim} end: {total_feature_dim + torch.prod(torch.tensor(feature_dims)).item()}"  # noqa: E501
            )
            total_feature_dim += torch.prod(torch.tensor(feature_dims)).item()
        tokenizer_feature_dim = total_feature_dim

        # Add proprioception dimension
        proprioception_dim = self.obs_dim_dict.get("actor_obs", 0)
        total_feature_dim += proprioception_dim

        print(f"tokenizer_feature_dim: {tokenizer_feature_dim}")  # noqa: T201
        print(f"proprioception_dim: {proprioception_dim}")  # noqa: T201

        # Create a single 2D tensor (B, F) including both encoder features and proprioception
        example_input = torch.randn(batch_size, total_feature_dim, device=device)

        example_dict = {
            "tokenizer": torch.randn(batch_size, tokenizer_feature_dim, device=device),
            "proprioception": torch.randn(batch_size, proprioception_dim, device=device),
        }

        return example_input, example_dict