"""Discriminate Rainer's hypotheses: run the trained recurrence FAR beyond the 16-segment budget
and watch the fate of trajectories that FAIL at segment 16.
  - settle to CORRECT later        => transient that would self-resolve (more compute helps)
  - settle to WRONG (drift->0)      => multistable WRONG attractor (genuine bistability)
  - never settle (drift stays high) => chaotic saddle / persistent non-convergence
Plain forward (no JVP). Saves per-segment decoded-exactness and per-segment z_H drift.
"""
from __future__ import annotations
import sys, argparse
from pathlib import Path
import numpy as np
import torch

sys.path.insert(0, "/home/yurenh2/rrm/research/flossing")
from diagnose_trm_joint_maze import load_model, load_test_samples


def main():
    ap = argparse.ArgumentParser()
    ap.add_argument("--ckpt-root", required=True)
    ap.add_argument("--ckpt-name", required=True)
    ap.add_argument("--data", required=True)
    ap.add_argument("--n", type=int, default=512)
    ap.add_argument("--batch-size", type=int, default=32)
    ap.add_argument("--n-seg", type=int, default=128)
    ap.add_argument("--seed", type=int, default=0)
    ap.add_argument("--out", required=True)
    args = ap.parse_args()
    device = "cuda"
    model, cfg, train_meta = load_model(Path(args.ckpt_root), args.ckpt_name, device)
    inner = model.inner
    test = load_test_samples(Path(args.data), args.n, 0, 1, args.seed)
    n = len(test["inputs"]); pe = inner.puzzle_emb_len

    EX, DR, IDX = [], [], []
    for s in range(0, n, args.batch_size):
        e = min(s + args.batch_size, n)
        batch = {k: test[k][s:e].to(device) for k in ["inputs", "labels", "puzzle_identifiers"]}
        B = batch["inputs"].shape[0]
        seq_full = inner.config.seq_len + pe; hidden = inner.config.hidden_size
        with torch.no_grad():
            z_H = inner.H_init.unsqueeze(0).expand(B, seq_full, hidden).clone().to(inner.forward_dtype)
            z_L = inner.L_init.unsqueeze(0).expand(B, seq_full, hidden).clone().to(inner.forward_dtype)
            seq_info = dict(cos_sin=inner.rotary_emb() if hasattr(inner, "rotary_emb") else None)
            inp_emb = inner._input_embeddings(batch["inputs"], batch["puzzle_identifiers"])
            labels = batch["labels"]; mask = labels > 0
            prev_zH = None; ex_seg, dr_seg = [], []
            for seg in range(args.n_seg):
                for _h in range(inner.config.H_cycles):
                    for _l in range(inner.config.L_cycles):
                        z_L = inner.L_level(z_L, z_H + inp_emb, **seq_info)
                    z_H = inner.L_level(z_H, z_L, **seq_info)
                p = inner.lm_head(z_H)[:, pe:].float().argmax(-1)
                ex_seg.append(((p == labels) | ~mask).all(-1).float().cpu())
                dr_seg.append((torch.zeros(B) if prev_zH is None
                               else (z_H - prev_zH).float().flatten(1).norm(dim=1).cpu()))
                prev_zH = z_H.detach()
        EX.append(torch.stack(ex_seg, 1).numpy()); DR.append(torch.stack(dr_seg, 1).numpy())
        IDX.append(test["idx"][s:e])
        print(f"  [{e}/{n}] exact@16={torch.stack(ex_seg,1)[:,15].mean():.3f} exact@{args.n_seg}={torch.stack(ex_seg,1)[:,-1].mean():.3f}", flush=True)

    np.savez_compressed(args.out, exact_seg=np.concatenate(EX), drift_seg=np.concatenate(DR),
                        idx=np.concatenate(IDX))
    print("saved", args.out)


if __name__ == "__main__":
    main()