Blame for inference_example.py

#!/usr/bin/env python3
"""Standalone inference example for citan/plgec-herbert-large-v2.

Public dependencies only: onnxruntime, tokenizers, numpy (+ stdlib).
Loads the fp32 ONNX model, tokenizer, label vocabulary and the
consumer-side thresholds.yaml from a directory laid out like this
repository (either the repository root or its onnx/ subdirectory),
decodes sentences with the settings fixed at publication, applies the
per-class filter, and prints one JSON object per sentence:

    {"sentence": ..., "corrected": ..., "edits": [{"token_idx",
     "char_span", "original", "replacement", "tag", "class",
     "confidence", "iteration"}, ...]}

Decode semantics (fixed at publication; transcribed from the released
checkpoint's threshold selection): keep_confidence_bias 0.25,
min_error_probability 0.20, max_iters 1 — a single conservative pass.
A word is edited only when 1 - min(1, P($KEEP) + 0.25) > 0.20 AND the
top non-KEEP tag's probability > 0.20; confidence is the chosen tag's
raw softmax probability under identity temperature (T = 1.0 — the v2
calibration block ships the explicit identity, no fitted constant).
Edits are applied right-to-left on token indices; an insertion before
the first token reports token_idx -1.

Span caveat: an insertion after the FINAL token reports a character
span whose end is one codepoint past the end of the text by design.

$MERGE and other tags that do not render as single-token edits are
skipped, exactly like the reference decoder.

File map of this repository: vocab.json at the root is the GECToR
LABEL vocabulary (6,757 tags, tag_to_id/id_to_tag) — onnx/vocab.json
is the tokenizer's BPE word vocabulary; the two are distinguished by
shape, this example resolves them by predicate. thresholds.yaml is the
schema-v3 consumer-side filter (per-class bars, conf disabled by
default with an optional floor, calibration block, `; -> ,` blocklist
rule); thresholds.sha256 beside it carries the file's sha256 as
published (sha256sum format) for local integrity checks.

Phase 8 (plan 08-02): the thresholds file may additionally carry a
schema-v2 calibration block (temperature T — applied as
softmax(logits / T), argmax-preserving because T divides the logits
PRE-softmax, at the same pre-decode point as the reference torch leg)
and an exact-token blocklist (REPLACE-shaped `; -> ,`-style rules,
dropped POST-decode in the same filter stage as the per-class bars —
never re-decodes). Both apply only from schema_version 2; absent
sections decode at the byte-identical v1 shape (T=1.0, no suppression).
The calibration + blocklist code is DUPLICATED from
publish/calibration.py — standalone-by-design (CONTEXT D-15); zero new
dependencies.

Phase 11 (plan 11-03, OQ-2): thresholds schema v3 adds an optional
per-class confidence `floor` — an edit of a class whose block carries
a floor survives only if its confidence clears BOTH the class bar AND
the floor (ADDITIVE; an absent floor key is exact v2 behavior),
dropped in the same post-decode filter stage as the bars and the
blocklist (never re-decodes). tests/test_calibration_three_runtime_
parity.py is the drift guard across the three runtimes.

No INT8 graph exists in this repository (no onnx_int8/ sibling): the
v2 artifact is fp32 only. The v1 repository keeps its own INT8
evidence; it is not referenced here.
"""

from __future__ import annotations

import json
import math
import re
import sys
from pathlib import Path

import numpy as np
import onnxruntime as ort
from tokenizers import Tokenizer

REPO_ID = "citan/plgec-herbert-large-v2"
KEEP, DELETE = "$KEEP", "$DELETE"
REPLACE_PREFIX, APPEND_PREFIX = "$REPLACE_", "$APPEND_"

# Published decode triple (fixed at publication — the Stage-IV
# threshold selection, combo 105: keep_confidence_bias 0.25 /
# min_error_probability 0.20 / max_iters 1).
KEEP_CONFIDENCE_BIAS = 0.25
MIN_ERROR_PROBABILITY = 0.20
MAX_ITERS = 1
DECODE_CHUNK = 32  # sentences per model call — padding stays reference-identical

# Session options matching the reference decode (deterministic output).
ORT_SPIN = {"session.intra_op.allow_spinning": "1",
            "session.intra_op.spin_duration_us": "1000",
            "session.intra_op.spin_backoff_max": "8"}

# Canonical word tokenization: Polish/Latin word runs + single-char tokens.
WORD_RUN = r"[A-Za-ząćęłńóśźżĄĆĘŁŃÓŚŹŻ0-9]+"
_TOKEN_RE = re.compile(WORD_RUN + r"|[^\s]")

# Orthography swap pairs (attribution fallback when a tag carries no
# class metadata in the shipped vocabulary).
_TWO_CHAR_SWAPS = {"rz": "ż", "ch": "h"}
_ONE_CHAR_SWAPS = {"ż": "rz", "ó": "u", "u": "ó", "ą": "ę", "ę": "ą", "h": "ch"}


def tokenize_words(text):
    return _TOKEN_RE.findall(text)


def token_char_spans(sentence):
    return [(m.start(), m.end()) for m in _TOKEN_RE.finditer(sentence)]


def edit_char_span(sentence, edit, spans):
    """(start, end) codepoints an edit touches on the source text."""
    idx = edit.get("token_idx")
    if idx is None or idx >= len(spans):
        return (0, 0)
    if idx < 0:  # leading insertion
        return (0, spans[0][0]) if spans else (0, 0)
    start, end = spans[idx]
    if edit["tag"].startswith(APPEND_PREFIX):
        nxt = spans[idx + 1][0] if idx + 1 < len(spans) else len(sentence)
        return (end, max(end + 1, nxt)) if nxt <= end else (end, nxt)
    return (start, end)


def _orth_swap_transform(token):
    result = token
    lowered = token.lower()
    sites, i = [], 0
    while i < len(lowered):
        two = lowered[i:i + 2]
        if two in _TWO_CHAR_SWAPS:
            sites.append((i, 2, _TWO_CHAR_SWAPS[two]))
            i += 2
            continue
        if lowered[i] in _ONE_CHAR_SWAPS:
            sites.append((i, 1, _ONE_CHAR_SWAPS[lowered[i]]))
        i += 1
    for start, match_len, replacement in sorted(sites, reverse=True):
        span = result[start:start + match_len]
        repl = replacement
        if span[:1].isupper():
            repl = repl[:1].upper() + repl[1:]
        result = result[:start] + repl + result[start + match_len:]
    return result


def attribute_class(edit, tag_class_metadata):
    """Tag → class, metadata-first; orth-swap fallback for bare replaces."""
    tag = edit.get("tag", "")
    if tag_class_metadata:
        classes = tag_class_metadata.get(tag)
        if classes:
            return classes[0]  # pre-sorted at vocabulary build time
    if tag.startswith(REPLACE_PREFIX):
        original, replacement = edit["original"], edit["replacement"]
        if replacement != original and replacement == _orth_swap_transform(
                original):
            return "orth"
        return "infl"
    return "unknown"


# ---------------------------------------------------------------------------
# Consumer config (schema v2/v3 — plans 08-02 and 11-03; CONTEXT
# D-12/D-13/D-15).
#
# DUPLICATED from publish/calibration.py — standalone-by-design (CONTEXT
# D-15): the serve CLI imports the single definition site; the
# standalone legs (this file and mcp/server.py) carry byte-identical
# copies of this whole block (the parity tests and
# tests/test_thresholds_yaml_schema_v2.py are the drift guards). No
# pyyaml here — the public-deps contract keeps the parser hand-rolled.
# ---------------------------------------------------------------------------
SCHEMA_VERSION_CURRENT = 3  # Phase 8 (D-13): v2 added schema_version +
# calibration + blocklist top-level sections; Phase 11 (plan 11-03,
# OQ-2) bumps to 3 — the optional per-class confidence `floor` key
# (ADDITIVE: an edit of the class must clear BOTH the class bar AND
# the floor; an absent floor key is exact v2 behavior).


def _yaml_unquote(value):
    """Strip one matching surrounding quote pair from a yaml scalar."""
    if len(value) >= 2 and value[0] == value[-1] and value[0] in ("'", '"'):
        return value[1:-1]
    return value


def _yaml_float(value, path, key):
    """Scalar -> float, rejecting bool spellings (the L-06 trap) and any
    non-numeric text with the fail-closed ValueError style."""
    if value in ("true", "false"):
        raise ValueError(f"{path}: {key} {value!r} must be a number")
    try:
        return float(value)
    except ValueError:
        raise ValueError(f"{path}: {key} {value!r} must be a number") from None


def load_thresholds(path):
    """Hand-rolled YAML reader for the shipped thresholds file (no pyyaml
    — the public-deps contract).

    Parses the full schema v2 plus the v3 per-class floor key: the
    per-class mapping {class: {min_error_probability: float,
    enabled: bool, floor: float in (0, 1] OPTIONAL — Phase 11, plan
    11-03: the ADDITIVE confidence floor, an absent key is exact v2
    behavior}} PLUS the top-level
    schema_version int scalar (a FUTURE version > 3 is refused loudly —
    an old runtime must never silently drop new semantics), the
    calibration block {temperature: float > 0, t_int8: null-or-float
    > 0} and the blocklist list-of-flat-mappings (string class/from/to/
    reason, bool enabled, optional int >= 0 min_tokens_before guard).
    Returns the FULL document: per-class keys plus the special keys
    "schema_version", "calibration", "blocklist" whenever present in
    the file (mirroring the serve CLI's loader; the Corrector gates
    their APPLICATION on schema_version >= 2 — a v1 file's stray
    sections parse but never apply). Any other top-level scalar stays a
    hard ValueError; malformed v2 values fail closed, never a repaired
    default.
    """
    root, current = {}, None
    section = "class"  # active top-level section: class|calibration|blocklist
    schema_version, calibration, blocklist, rule = None, None, None, None
    for raw in Path(path).read_text(encoding="utf-8").splitlines():
        line = raw.split("#", 1)[0].rstrip()
        if not line.strip():
            continue
        indent = len(line) - len(line.lstrip())
        stripped = line.strip()
        list_item = stripped.startswith("-")
        if list_item:
            stripped = stripped[1:].strip()
        key, _, value = stripped.partition(":")
        key, value = key.strip(), value.strip()
        if list_item:
            if (indent == 0 or section != "blocklist"
                    or blocklist is None):
                raise ValueError(f"{path}: unexpected list item {raw!r}")
            rule = {}
            blocklist.append(rule)
            if not key:
                continue  # bare '-'; payload on the following lines
        elif indent == 0:
            rule = None
            if key == "schema_version":
                if not value.isdigit():
                    raise ValueError(f"{path}: schema_version {value!r} "
                                     "is not an integer")
                if int(value) > SCHEMA_VERSION_CURRENT:
                    raise ValueError(
                        f"{path}: schema_version={int(value)} > current "
                        f"runtime's {SCHEMA_VERSION_CURRENT}; upgrade "
                        "the runtime")
                schema_version = int(value)
                continue
            if value:
                raise ValueError(f"{path}: top-level scalar {key!r} — "
                                 "expected class blocks")
            if key == "calibration":
                section, calibration, current = "calibration", {}, None
            elif key == "blocklist":
                section, blocklist, current = "blocklist", [], None
            else:
                section, current = "class", root.setdefault(key, {})
            continue
        # indented content (or the payload of a "- key: value" row)
        if section == "class":
            if current is None or value == "":
                raise ValueError(f"{path}: unexpected line {raw!r}")
            if key == "floor":
                # Phase 11 (plan 11-03, OQ-2 additive): optional
                # per-class confidence floor, strictly in (0, 1];
                # _yaml_float rejects the true/false bool spellings
                # (the L-06 trap) and any non-numeric text.
                floor = _yaml_float(value, path, "class floor")
                if not 0.0 < floor <= 1.0:
                    raise ValueError(f"{path}: class floor {value!r} "
                                     "must be a number in (0, 1]")
                current["floor"] = floor
            elif value in ("true", "false"):
                current[key] = value == "true"
            else:
                current[key] = float(value)
        elif section == "calibration":
            if calibration is None:  # unreachable: the section switch sets it
                raise ValueError(f"{path}: unexpected line {raw!r}")
            if key == "temperature":
                temperature = _yaml_float(value, path,
                                          "calibration temperature")
                if not math.isfinite(temperature) \
                        or not temperature > 0:
                    # CR-01: 'not x > 0' rejects nan but NOT inf
                    raise ValueError(f"{path}: calibration temperature "
                                     f"{value!r} must be a finite "
                                     "number > 0")
                calibration["temperature"] = temperature
            elif key == "t_int8":
                if value in ("", "null", "~"):
                    calibration["t_int8"] = None  # reserved slot (v2 ships null)
                else:
                    t_int8 = _yaml_float(value, path, "calibration t_int8")
                    if not math.isfinite(t_int8) or not t_int8 > 0:
                        raise ValueError(f"{path}: calibration t_int8 "
                                         f"{value!r} must be a finite "
                                         "number > 0 or null")
                    calibration["t_int8"] = t_int8
            else:
                raise ValueError(f"{path}: unexpected calibration key "
                                 f"{key!r}")
        else:  # section == "blocklist"
            if rule is None:
                raise ValueError(f"{path}: unexpected line {raw!r}")
            if key in ("class", "from", "to", "reason"):
                rule[key] = _yaml_unquote(value)
            elif key == "enabled":
                if value not in ("true", "false"):
                    raise ValueError(f"{path}: blocklist rule enabled "
                                     f"{value!r} must be a bool")
                rule["enabled"] = value == "true"
            elif key == "min_tokens_before":
                if not value.isdigit():  # digits-only: rejects -1/true/text
                    raise ValueError(f"{path}: blocklist rule "
                                     "min_tokens_before "
                                     f"{value!r} must be an integer >= 0")
                rule["min_tokens_before"] = int(value)
            else:
                raise ValueError(f"{path}: unexpected blocklist rule key "
                                 f"{key!r}")
    if calibration is not None and "temperature" not in calibration:
        raise ValueError(f"{path}: calibration block missing 'temperature'")
    for rule in blocklist or []:
        for required in ("class", "from", "to"):
            if required not in rule:
                raise ValueError(f"{path}: blocklist rule missing "
                                 f"{required!r}")
    document = dict(root)
    if schema_version is not None:
        document["schema_version"] = schema_version
    if calibration is not None:
        document["calibration"] = calibration
    if blocklist is not None:
        document["blocklist"] = blocklist
    return document


def blocklist_match(edit: dict, rules) -> bool:
    """True if the edit is BLOCKED by an enabled rule (drop it).

    DUPLICATED from publish/calibration.py — standalone-by-design
    (CONTEXT D-15); keep byte-identical across the two standalone legs.

    Match semantics (CONTEXT D-12 + the match-discretion resolution):
    $REPLACE_-shaped tags only, exact string equality of
    (original, replacement) == (from, to), and the optional per-rule
    integer guard min_tokens_before — the rule fires only when the
    edit's token_idx >= the guard (absent guard = 0 = unconditional).
    $APPEND_/$DELETE never match (RESEARCH Pitfall 4); ';'/';;'/','-
    adjacent near-misses never match (exact tokens only).
    """
    for rule in rules or []:
        if not isinstance(rule, dict):
            continue
        if not rule.get("enabled", True):
            continue  # per-rule disable path (D-14, conf.enabled precedent)
        # exact-token REPLACE match — the only tag shape allowed
        if not str(edit.get("tag", "")).startswith("$REPLACE_"):
            continue
        if (edit.get("original") == rule.get("from")
                and edit.get("replacement") == rule.get("to")):
            guard = rule.get("min_tokens_before", 0) or 0
            token_idx = edit.get("token_idx")
            if not isinstance(token_idx, int) or isinstance(token_idx, bool):
                token_idx = 0  # defensive: real REPLACE edits carry int idx
            if token_idx >= int(guard):
                return True
    return False


def _first_json(candidates, predicate, what):
    for cand in candidates:
        if cand.is_file():
            data = json.loads(cand.read_text(encoding="utf-8"))
            if predicate(data):
                return data
    raise SystemExit(f"FATAL: {what} not found under: "
                     + ", ".join(str(c) for c in candidates))


class Corrector:
    """ONNX GECToR decoder over the published v2 checkpoint layout."""

    def __init__(self, model_dir, thresholds=None):
        model_dir = Path(model_dir)
        # v2 ships fp32 only — no INT8 graph exists in this repository
        # (D-09); the candidates are the two fp32 layouts (onnx/ subdir
        # or a flat download).
        candidates = (model_dir / "onnx" / "model.onnx",
                      model_dir / "model.onnx")
        onnx_path = next((p for p in candidates if p.is_file()), None)
        tok_path = next((p for p in (model_dir / "tokenizer.json",
                                     model_dir / "onnx" / "tokenizer.json")
                         if p.is_file()), None)
        if onnx_path is None or tok_path is None:
            raise SystemExit(
                f"FATAL: {model_dir} is not a plgec-herbert-large-v2 "
                "download (need onnx/model.onnx and tokenizer.json)")
        vocab = _first_json(
            [model_dir / "vocab.json", model_dir / "onnx" / "vocab.json"],
            lambda d: isinstance(d, dict) and "tag_to_id" in d
            and "id_to_tag" in d,
            "GECToR label vocabulary (vocab.json with tag_to_id/id_to_tag)")
        self.tag_to_id = vocab["tag_to_id"]
        self.id_to_tag = {int(k): v for k, v in vocab["id_to_tag"].items()}
        self.keep_id = self.tag_to_id[KEEP]
        self.tag_class_metadata = vocab.get("tag_class_metadata") or None

        options = ort.SessionOptions()
        options.intra_op_num_threads = 8
        options.execution_mode = ort.ExecutionMode.ORT_SEQUENTIAL
        options.graph_optimization_level = ort.GraphOptimizationLevel.ORT_ENABLE_ALL
        for key, value in ORT_SPIN.items():
            options.add_session_config_entry(key, value)
        self.session = ort.InferenceSession(str(onnx_path), options,
                                            providers=["CPUExecutionProvider"])
        self.tokenizer = Tokenizer.from_file(str(tok_path))
        pad = self.tokenizer.token_to_id("<pad>")
        self.pad_id = 0 if pad is None else int(pad)
        self.thresholds = thresholds

    # -- consumer-side per-class filter (applied AFTER decode) ----------
    def _drops(self, edit_class, confidence):
        if not self.thresholds:
            return False
        block = (self.thresholds.get(edit_class)
                 or self.thresholds.get("default"))
        if not block:
            return False
        if not block.get("enabled", True):
            return True
        if confidence < float(block.get("min_error_probability", 0.0)):
            return True
        # Phase 11 (plan 11-03, OQ-2 additive): the optional per-class
        # confidence `floor` (schema v3) — the edit must ALSO clear it
        # (inclusive at the boundary), in the same post-decode filter
        # stage; never re-decodes; an absent key is exact v2 behavior.
        # Duplicated from the serve CLI's _threshold_drops semantics
        # (standalone-by-design, D-15) — the three-runtime parity test
        # is the drift guard.
        floor = block.get("floor")
        return floor is not None and confidence < float(floor)

    # -- Phase 8 v2 consumer config (plan 08-02) ------------------------
    # DUPLICATED from publish/calibration.py semantics — standalone-by-
    # design (CONTEXT D-15); read dynamically per correct() call so
    # post-construction threshold mutation behaves like the per-class
    # bars. Both keys apply only from schema_version 2 (a v1 file's
    # stray sections parse but never apply — backward compat).
    def _calibration_temperature(self):
        """Decode temperature T: softmax(logits / T), argmax-preserving
        because T divides the LOGITS pre-softmax (CONTEXT D-01, never a
        post-softmax rescale). Absent calibration block / v1 file ->
        T=1.0 exact identity. The shipped v2 file carries the explicit
        identity temperature (T = 1.0)."""
        if not self.thresholds:
            return 1.0
        if self.thresholds.get("schema_version", 1) < 2:
            return 1.0
        block = self.thresholds.get("calibration") or {}
        return float(block.get("temperature", 1.0))

    def _active_blocklist_rules(self):
        """Blocklist rules applying to this corrector (schema v2+ only)."""
        if not self.thresholds:
            return []
        if self.thresholds.get("schema_version", 1) < 2:
            return []
        rules = self.thresholds.get("blocklist")
        return list(rules) if isinstance(rules, list) else []

    def _extract_edits(self, probs_row, positions, word_ids, words):
        edits = []
        for pos in positions:
            position_probs = probs_row[pos]
            keep_conf = min(1.0,
                            float(position_probs[self.keep_id])
                            + KEEP_CONFIDENCE_BIAS)
            if 1.0 - keep_conf <= MIN_ERROR_PROBABILITY:
                continue
            masked = position_probs.copy()
            masked[self.keep_id] = -1.0
            top_id = int(np.argmax(masked))
            top_p = float(position_probs[top_id])
            if top_p <= MIN_ERROR_PROBABILITY:
                continue
            tag = self.id_to_tag[top_id]
            word_id = word_ids[pos] if pos < len(word_ids) else None
            if tag == DELETE:
                if word_id is None:
                    continue
                edits.append({"token_idx": word_id, "original": words[word_id],
                              "replacement": "", "tag": tag,
                              "confidence": top_p})
            elif tag.startswith(REPLACE_PREFIX):
                if word_id is None:
                    continue
                edits.append({"token_idx": word_id, "original": words[word_id],
                              "replacement": tag[len(REPLACE_PREFIX):],
                              "tag": tag, "confidence": top_p})
            elif tag.startswith(APPEND_PREFIX):
                appended = tag[len(APPEND_PREFIX):]
                edits.append({"token_idx": word_id if word_id is not None else -1,
                              "original": "" if word_id is None else words[word_id],
                              "replacement": appended, "tag": tag,
                              "confidence": top_p})
        return edits


def _apply_edits(words, edits):
    """Apply one pass's edits; descending token order keeps indices valid."""
    updated = list(words)
    for edit in sorted((e for e in edits if e["token_idx"] >= 0),
                       key=lambda e: e["token_idx"], reverse=True):
        idx = edit["token_idx"]
        if edit["tag"] == DELETE:
            del updated[idx]
        elif edit["tag"].startswith(REPLACE_PREFIX):
            updated[idx] = edit["replacement"]
        elif edit["tag"].startswith(APPEND_PREFIX):
            updated.insert(idx + 1, edit["replacement"])
    for edit in (e for e in edits if e["token_idx"] == -1):
        if edit["tag"].startswith(APPEND_PREFIX):
            updated.insert(0, edit["replacement"])
    return updated


def correct(corrector, texts):
    """[{sentence, corrected, edits}] for texts, reference-batched."""
    originals = list(texts)
    current = list(texts)
    all_edits = [[] for _ in current]
    for _iteration in range(1, MAX_ITERS + 1):
        fired_any = False
        for c in range(0, len(current), DECODE_CHUNK):
            chunk = current[c:c + DECODE_CHUNK]
            words_per_sentence = [tokenize_words(s) for s in chunk]
            encodings = [corrector.tokenizer.encode(words, is_pretokenized=True)
                         for words in words_per_sentence]
            id_rows = [enc.ids for enc in encodings]
            wid_rows = [enc.word_ids for enc in encodings]
            longest = max(len(ids) for ids in id_rows)
            input_ids = np.array(
                [ids + [corrector.pad_id] * (longest - len(ids))
                 for ids in id_rows], dtype=np.int64)
            attention = np.array(
                [[1] * len(ids) + [0] * (longest - len(ids))
                 for ids in id_rows], dtype=np.int64)
            logits = corrector.session.run(None, {
                "input_ids": input_ids,
                "attention_mask": attention,
                "token_type_ids": np.zeros_like(input_ids)})[0]
            # Softmax in float64 (accurate, deterministic across numpy
            # builds), cast to float32 to mirror the reference decoder's
            # float32 probability tensor: gate comparisons and the
            # emitted confidence both read the float32 values. Kernel
            # level difference vs the torch reference is bounded and
            # test-pinned (tests/test_public_example_parity.py).
            # Phase 8 (plan 08-02, CALIB-01): the consumer-side
            # temperature T enters HERE, pre-softmax on the shifted
            # logits — softmax((l - max) / T) == softmax(l / T), the
            # argmax-preserving form (D-01) at the same pre-decode
            # point as the torch leg; T = 1.0 divides exactly, so the
            # identity path stays byte-identical (the v2 file ships
            # the explicit identity).
            temperature = corrector._calibration_temperature()
            shifted = (logits - logits.max(axis=-1, keepdims=True)
                       ).astype(np.float64)
            shifted /= temperature
            exp = np.exp(shifted)
            probs = (exp / exp.sum(axis=-1, keepdims=True)
                     ).astype(np.float32)
            for row, (words, word_ids) in enumerate(
                    zip(words_per_sentence, wid_rows)):
                seen, positions = set(), []
                for pos, word_id in enumerate(word_ids):
                    if word_id is not None and word_id not in seen:
                        seen.add(word_id)
                        positions.append(pos)
                edits = corrector._extract_edits(
                    probs[row], [0] + positions, word_ids, words)
                if edits:
                    fired_any = True
                    for edit in edits:
                        edit["iteration"] = _iteration
                    all_edits[c + row].extend(edits)
                    words_per_sentence[row] = _apply_edits(words, edits)
                    current[c + row] = " ".join(words_per_sentence[row])
        if not fired_any:
            break
    results = []
    for source_text, final, edits in zip(originals, current, all_edits):
        words = tokenize_words(source_text)
        spans = token_char_spans(source_text)
        surviving = []
        blocklist_rules = corrector._active_blocklist_rules()
        for edit in edits:
            edit_class = attribute_class(edit, corrector.tag_class_metadata)
            if corrector._drops(edit_class, edit["confidence"]):
                continue
            # Phase 8 (plan 08-02, SERVE-03): exact-token blocklist drop
            # in the same post-decode filter stage as the per-class bars
            # — never re-decodes, never reorders.
            if blocklist_match(edit, blocklist_rules):
                continue
            surviving.append({
                "token_idx": edit["token_idx"],
                "char_span": list(edit_char_span(source_text, edit, spans)),
                "original": edit["original"],
                "replacement": edit["replacement"],
                "tag": edit["tag"],
                "class": edit_class,
                "confidence": edit["confidence"],
                "iteration": edit["iteration"],
            })
        corrected = (" ".join(_apply_edits(words, surviving))
                     if surviving else source_text)
        results.append({"sentence": source_text, "corrected": corrected,
                        "edits": surviving})
    return results


def main(argv):
    import argparse
    parser = argparse.ArgumentParser(
        description="Standalone inference for " + REPO_ID
                    + " (public deps: onnxruntime, tokenizers, numpy).")
    parser.add_argument("sentences", nargs="+",
                        help="sentence(s) to correct (quoted)")
    parser.add_argument("--model-dir", default=str(Path(__file__).parent),
                        help="model download directory (default: this "
                             "script's directory)")
    parser.add_argument("--thresholds", default=None,
                        help="per-class thresholds YAML (default: "
                             "thresholds.yaml in the model dir, if present; "
                             "'none' disables consumer-side filtering)")
    args = parser.parse_args(argv)

    thresholds = args.thresholds
    if thresholds == "none":
        thresholds = None
    elif thresholds is None:
        candidate = Path(args.model_dir) / "thresholds.yaml"
        thresholds = str(candidate) if candidate.is_file() else None
    corrector = Corrector(args.model_dir,
                          load_thresholds(thresholds)
                          if thresholds else None)
    for record in correct(corrector, args.sentences):
        print(json.dumps(record, ensure_ascii=False))


if __name__ == "__main__":
    main(sys.argv[1:])