"""Round zero and the per-family noise floor (learning-harness, Req 8).

Before anything learns, every family gets the same detector and is measured against itself. Running a
pair several times at the same settings does not give the same answer: the chat provider offers no seed,
so the spread between runs is real and unavoidable. That spread is the family's noise floor, and it
becomes the budget a later round must stay inside before a cross-family change counts as a regression.
Choosing a budget instead of measuring one would be a guess dressed as a threshold.

Artifacts are keyed by detector model, so a second model is baselined by changing the model and running
again. Configurations are never touched by a model swap, which is what makes the two numbers comparable
and what makes reconsidering the model cheap.
"""

from __future__ import annotations

import json
import math
import re
import tempfile
from collections.abc import Callable, Mapping, Sequence
from dataclasses import dataclass, field
from pathlib import Path

from ..findings import StaticFinding
from ..pairs import PairCase
from .classify import classify_pair
from .detectors import FamilyConfig, write_default_configs
from .families import FamilyTaxonomy
from .journal import Archive, Attribution, LearningJournal, RoundRecord
from .proposer import Proposal, Proposer
from .scoring import FamilyMetrics, PairFamilyScore, aggregate, score_pair_family

DEFAULT_SLICES = ("vibe-py", "agent-vfc")  # the web families, where real-world code and dangerous fruit coincide
NON_GATING_FAMILIES = frozenset({"memory"})  # measured on the vendored slice, never allowed to fail a round
DEFAULT_K_RUNS = 5
Scan = Callable[[Path], list[StaticFinding]]


@dataclass(frozen=True)
class NoiseFloor:
    """How much a family disagrees with itself between runs, and the budget that follows from it."""

    family: str
    k_runs: int
    pairs: int
    flaky_pairs: int
    negative_flip_rate: float
    budget_flips: int
    gates: bool = True

    def to_dict(self) -> dict[str, object]:
        return {
            "family": self.family,
            "k_runs": self.k_runs,
            "pairs": self.pairs,
            "flaky_pairs": self.flaky_pairs,
            "negative_flip_rate": self.negative_flip_rate,
            "budget_flips": self.budget_flips,
            "gates": self.gates,
        }


@dataclass(frozen=True)
class BaselineReport:
    model: str
    k_runs: int
    taxonomy_version: str
    slices: tuple[str, ...]
    thinking: bool = False  # the condition that produced these numbers, so two modes cannot be read as one
    floors: dict[str, NoiseFloor] = field(default_factory=dict)
    metrics: dict[str, dict[str, object]] = field(default_factory=dict)
    # `<slice>/<family>`: the budgets stay per family, but vibe-py and agent-vfc are different worlds and one
    # pooled number hides which of them moved (Req 8.4).
    per_slice: dict[str, dict[str, object]] = field(default_factory=dict)
    scores: tuple[PairFamilyScore, ...] = ()
    cost_usd: float = 0.0

    def to_dict(self) -> dict[str, object]:
        return {
            "model": self.model,
            "k_runs": self.k_runs,
            "taxonomy_version": self.taxonomy_version,
            "slices": list(self.slices),
            "thinking": self.thinking,
            "cost_usd": self.cost_usd,
            "floors": {name: floor.to_dict() for name, floor in sorted(self.floors.items())},
            "metrics": {name: dict(block) for name, block in sorted(self.metrics.items())},
            "per_slice": {name: dict(block) for name, block in sorted(self.per_slice.items())},
        }


def run_baseline(
    cases: Sequence[PairCase],
    *,
    taxonomy: FamilyTaxonomy,
    configs_dir: Path,
    scan_factory: Callable[[FamilyConfig], Scan],
    model: str,
    out_dir: Path,
    slices: Sequence[str] = DEFAULT_SLICES,
    k_runs: int = DEFAULT_K_RUNS,
    prompt: str | None = None,
    spent_usd: Callable[[], float] | None = None,
    cutoff: str = "",
    thinking: bool = False,
    resume: bool = False,
) -> BaselineReport:
    """Clone one detector into every family, measure each family **with its own configuration**, write the artifacts.

    The factory is the point. One shared `scan` would score every family with one detector, and since the generalist
    tags its findings `family:unknown` — which earns no credit against any real family, by the taxonomy's own
    decision that abstention is not a partial answer — every family but `unknown` would baseline at a structural
    zero and the noise floors would all be nil (Req 8.2).
    """
    from ..tool_hunter import _SYSTEM_PROMPT
    from .detectors import load_family_configs

    if k_runs < MIN_K_RUNS:
        raise ValueError(f"round zero scores at least three runs per pair; {k_runs} was asked for")
    if not configs_dir.exists():
        write_default_configs(configs_dir, taxonomy, prompt=prompt or _SYSTEM_PROMPT, version="0")
    configs = load_family_configs(configs_dir, taxonomy)
    selected = [case for case in cases if case.slice in set(slices)]
    # Every pair is written down as it is measured. Round zero over the vfc slice is 1760 detector runs and hours of
    # paid calls; accumulating in memory and persisting once at the end means a timeout, a kill or a machine going
    # away costs all of it. An exception already cost only one pair; nothing else did.
    checkpoint = out_dir / "baseline" / _artifact_key(model, slices, thinking) / "scores.jsonl"
    done = _checkpointed(checkpoint) if resume else {}
    if not resume and checkpoint.exists():
        checkpoint.unlink()
    scores = []
    for case in selected:
        name = _family_of(case, taxonomy)
        config = configs.get(name)
        if config is None:
            continue  # a family with no configuration is not measured rather than measured with someone else's
        if case.name in done:
            scores.append(done[case.name])
            continue
        try:
            score = score_case(case, scan_factory(config), taxonomy=taxonomy, runs=k_runs, family=name)
            scores.append(score)
            _append_score(checkpoint, score)
        except Exception:  # noqa: BLE001 — a provider hiccup costs one pair, not the whole run
            # Round zero is the most expensive thing this harness does. Raising here threw away everything already
            # measured and paid for, so the only honest response to a flaky endpoint was to run it all again.
            unreachable = PairFamilyScore(
                pair=case.name,
                family=name,
                slice=case.slice,
                fix_date=case.fix_date,
                runs=(),
                outcome="unscorable",
                unscorable_reason="detector_unreachable",
            )
            scores.append(unreachable)
            _append_score(checkpoint, unreachable)
    metrics = aggregate(scores, taxonomy=taxonomy, cutoff=cutoff)
    floors = {name: _floor(name, block, [item for item in scores if item.family == name], k_runs) for name, block in metrics.items()}
    report = BaselineReport(
        model=model,
        k_runs=k_runs,
        taxonomy_version=taxonomy.version,
        slices=tuple(slices),
        thinking=thinking,
        floors=floors,
        metrics={name: block.to_dict() for name, block in metrics.items()},
        per_slice={name: block.to_dict() for name, block in aggregate(scores, taxonomy=taxonomy, per_slice=True, cutoff=cutoff).items()},
        scores=tuple(scores),
        cost_usd=spent_usd() if spent_usd is not None else 0.0,
    )
    _write(out_dir, report)
    return report


def _append_score(path: Path, score: PairFamilyScore) -> None:
    """One line per pair, flushed, so an interrupted run keeps what it measured."""
    path.parent.mkdir(parents=True, exist_ok=True)
    payload = {
        "pair": score.pair,
        "family": score.family,
        "slice": score.slice,
        "fix_date": score.fix_date,
        "outcome": score.outcome,
        "runs": list(score.runs),
        "flips": score.flips,
        "other_findings_vuln": score.other_findings_vuln,
        "other_findings_fixed": score.other_findings_fixed,
        "fabricated_vuln": score.fabricated_vuln,
        "fabricated_fixed": score.fabricated_fixed,
        "rung": score.rung,
        "unscorable_reason": score.unscorable_reason,
    }
    with path.open("a", encoding="utf-8") as handle:
        handle.write(json.dumps(payload, sort_keys=True) + "\n")
        handle.flush()


def _checkpointed(path: Path) -> dict[str, PairFamilyScore]:
    """What a previous run of this exact baseline already measured and paid for."""
    if not path.is_file():
        return {}
    out: dict[str, PairFamilyScore] = {}
    for line in path.read_text(encoding="utf-8").splitlines():
        if not line.strip():
            continue
        try:
            row = json.loads(line)
        except json.JSONDecodeError:
            continue  # a line half-written when the run died is not a measurement
        out[str(row["pair"])] = PairFamilyScore(
            pair=str(row["pair"]),
            family=str(row["family"]),
            slice=str(row.get("slice", "")),
            fix_date=str(row.get("fix_date", "")),
            runs=tuple(row.get("runs", ())),
            outcome=row["outcome"],
            flips=int(row.get("flips", 0)),
            other_findings_vuln=int(row.get("other_findings_vuln", 0)),
            other_findings_fixed=int(row.get("other_findings_fixed", 0)),
            fabricated_vuln=int(row.get("fabricated_vuln", 0)),
            fabricated_fixed=int(row.get("fabricated_fixed", 0)),
            rung=row.get("rung", "suspicion"),
            unscorable_reason=row.get("unscorable_reason"),
        )
    return out


def score_case(case: PairCase, scan: Scan, *, taxonomy: FamilyTaxonomy, runs: int, family: str | None = None) -> PairFamilyScore:
    """Run one detector over both sides of one pair ``runs`` times and score it for its family.

    A pair the corpus already marked unscorable is never run: spending model calls on a row that cannot
    be scored buys nothing and would put its noise into a floor it does not belong in.
    """
    from ..pairs import _materialize_side, _overlay_scan

    name = family or _family_of(case, taxonomy)
    if case.unscorable:
        return PairFamilyScore(
            pair=case.name,
            family=name,
            runs=(),
            outcome="unscorable",
            slice=case.slice,
            fix_date=case.fix_date,
            unscorable_reason=case.unscorable,
        )
    with tempfile.TemporaryDirectory(prefix="ousast-round-") as scratch:
        vuln_root = _materialize_side(Path(scratch) / "vuln", case, side="vuln")
        fix_root = _materialize_side(Path(scratch) / "fixed", case, side="fixed")
        ranges = _overlay_scan(vuln_root).ranges
        fixed_ranges = _overlay_scan(fix_root).ranges
        vuln_runs = [scan(vuln_root) for _ in range(max(runs, 1))]
        fix_runs = [scan(fix_root) for _ in range(max(runs, 1))]
    return score_pair_family(
        case, name, vuln_runs, fix_runs, ranges=ranges, taxonomy=taxonomy, parse_ok=bool(ranges), fixed_ranges=fixed_ranges
    )


def compare_baselines(out_dir: Path) -> dict[str, dict[str, dict[str, object]]]:
    """Every baseline written under ``out_dir``, model by model, so two detectors can be read side by side."""
    root = out_dir / "baseline"
    table: dict[str, dict[str, dict[str, object]]] = {}
    for directory in sorted(path for path in root.iterdir() if path.is_dir()) if root.is_dir() else []:
        report = directory / "report.json"
        if not report.is_file():
            continue
        payload = json.loads(report.read_text(encoding="utf-8"))
        model = str(payload.get("model", directory.name))
        slices = tuple(str(item) for item in (payload.get("slices") or ()))
        conditions = [*(() if not payload.get("thinking") else ("thinking",)), *(() if slices == DEFAULT_SLICES else slices)]
        label = f"{model} ({', '.join(conditions)})" if conditions else model
        table[label] = {family: dict(block) for family, block in (payload.get("metrics") or {}).items()}
    return table


def _floor(family: str, metrics: FamilyMetrics, scores: Sequence[PairFamilyScore], k_runs: int) -> NoiseFloor:
    """A family's own disagreement between runs, as a rate and as a whole number of pairs."""
    scorable = [item for item in scores if item.outcome != "unscorable"]
    flaky = sum(1 for item in scorable if item.flips)
    rate = flaky / len(scorable) if scorable else 0.0
    return NoiseFloor(
        family=family,
        k_runs=k_runs,
        pairs=metrics.scorable,
        flaky_pairs=flaky,
        negative_flip_rate=rate,
        budget_flips=math.ceil(rate * metrics.scorable) if metrics.scorable else 0,
        gates=family not in NON_GATING_FAMILIES,
    )


def _family_of(case: PairCase, taxonomy: FamilyTaxonomy) -> str:
    for row in case.expected:
        if row.family:
            return str(row.family)
    answer = classify_pair(case, taxonomy, client=None)
    return answer.families[0] if answer.families else "unknown"


def _artifact_key(model: str, slices: Sequence[str], thinking: bool = False) -> str:
    """What identifies a baseline run: the detector model, and the slice selection when it is not the default.

    Keyed by model alone, a run over the memory-safety slice silently replaces the run over the web families and
    the published table shows one of them as if it were everything (Req 8.4)."""
    parts = [_slug(model)]
    if thinking:
        parts.append("thinking")
    if tuple(slices) != DEFAULT_SLICES:
        parts.append(_slug("-".join(sorted(slices))))
    return "-".join(parts)


def _write(out_dir: Path, report: BaselineReport) -> None:
    directory = out_dir / "baseline" / _artifact_key(report.model, report.slices, report.thinking)
    directory.mkdir(parents=True, exist_ok=True)
    payload = report.to_dict()
    (directory / "noise-floors.json").write_text(
        json.dumps({"model": report.model, "k_runs": report.k_runs, "floors": payload["floors"]}, indent=2, sort_keys=True) + "\n",
        encoding="utf-8",
    )
    (directory / "report.json").write_text(json.dumps(payload, indent=2, sort_keys=True) + "\n", encoding="utf-8")


def _slug(model: str) -> str:
    return re.sub(r"[^A-Za-z0-9._-]+", "-", model).strip("-") or "unnamed"


def load_noise_floors(out_dir: Path, model: str, slices: Sequence[str] = (), thinking: bool = False) -> dict[str, NoiseFloor]:
    """The budgets a later round must stay inside, as round zero measured them for this model."""
    path = out_dir / "baseline" / _artifact_key(model, slices or DEFAULT_SLICES, thinking) / "noise-floors.json"
    if not path.is_file():
        return {}
    payload = json.loads(path.read_text(encoding="utf-8"))
    floors: dict[str, NoiseFloor] = {}
    for name, block in (payload.get("floors") or {}).items():
        if isinstance(block, Mapping):
            floors[str(name)] = NoiseFloor(
                family=str(block.get("family", name)),
                k_runs=int(block.get("k_runs", DEFAULT_K_RUNS) or DEFAULT_K_RUNS),
                pairs=int(block.get("pairs", 0) or 0),
                flaky_pairs=int(block.get("flaky_pairs", 0) or 0),
                negative_flip_rate=float(block.get("negative_flip_rate", 0.0) or 0.0),
                budget_flips=int(block.get("budget_flips", 0) or 0),
                gates=bool(block.get("gates", True)),
            )
    return floors


MIN_K_RUNS = 3  # Req 3.5: a single run misses most real changes, so no stage may score with fewer


def run_learning_round(
    cases: Sequence[PairCase],
    *,
    family: str,
    taxonomy: FamilyTaxonomy,
    configs_dir: Path,
    proposer: Proposer,
    scan_factory: Callable[[FamilyConfig], Scan],
    model: str,
    journal: LearningJournal,
    archive: Archive,
    floors: Mapping[str, NoiseFloor],
    out_dir: Path,
    cost_cap_usd: float = 10.0,
    minibatch: int = 8,
    k_runs: int = MIN_K_RUNS,
    sweep_families: Sequence[str] = (),
    spent_usd: Callable[[], float] | None = None,
    trajectories: Callable[[], Sequence[Mapping[str, object]]] | None = None,
) -> RoundRecord:
    """One round: propose one change for one family, then let the evidence decide whether it stays.

    Staged so that the cheap answer comes first: a train minibatch, then the family's held-out pairs,
    then every other family. Each stage scores several runs per pair, because a single run misses most
    real changes. The proposer never sees a held-out pair, and the family directory is snapshotted before
    the change so any outcome other than acceptance leaves the tree exactly as it was found.
    """
    from .acceptance import DirectorySnapshot, bump_version, decide, within_budget
    from .detectors import load_family_configs
    from .proposer import apply_proposal, build_failure_facts, refuse_proposal
    from .split import is_teacher, refuse_if_holdout

    if k_runs < MIN_K_RUNS:
        raise ValueError(f"a stage scores at least three runs per pair; {k_runs} was asked for")
    round_number = journal.next_round()  # type: ignore[attr-defined]
    directory = out_dir / "rounds" / str(round_number)
    if directory.exists():
        from .journal import JournalError

        raise JournalError(f"round {round_number} already has a directory; history is append-only")
    configs = load_family_configs(configs_dir, taxonomy)
    config = configs[family]
    train = [case for case in cases if is_teacher(case) and _family_of(case, taxonomy) == family]
    holdout = [case for case in cases if case.split == "holdout" and _family_of(case, taxonomy) == family]
    batch = train[:minibatch]
    spent = 0.0

    def _score(rows: Sequence[PairCase], scan: Scan, name: str) -> list[PairFamilyScore]:
        return [score_case(case, scan, taxonomy=taxonomy, runs=k_runs, family=name) for case in rows]

    def _over_cap() -> bool:
        """Req 9.8: cost is read after every stage, so a round stops rather than finishing and then complaining."""
        nonlocal spent
        spent = spent_usd() if spent_usd is not None else 0.0
        return not within_budget(spent, cost_cap_usd)

    record = _round_record(round_number, family, None, taxonomy, config)
    try:
        before_scan = scan_factory(config)
        before_train = _score(batch, before_scan, family)
        before_hold = _score(holdout, before_scan, family)
    except Exception as exc:
        # These stages run before anything is applied, so there is nothing to revert — but they have already spent
        # money, and a round that leaves no record is a round nobody can account for. Measured: round 5 died on a
        # network read during its first stage and vanished.
        _finish(
            journal,
            directory,
            record,
            outcome="reverted",
            reason=f"stage_failed: {type(exc).__name__}",
            cost=spent_usd() if spent_usd is not None else 0.0,
            trajectories=trajectories,
        )
        raise
    if _over_cap():
        return _finish(
            journal, directory, record, outcome="reverted_cost", reason="cost_cap_exceeded", cost=spent, trajectories=trajectories
        )
    facts = build_failure_facts(before_train, family=family, config=config, journal=journal, train_pairs={case.name for case in train})
    proposal = proposer.propose(facts)  # type: ignore[attr-defined]
    record = _round_record(round_number, family, proposal, taxonomy, config)
    if proposal is None:
        # `no_proposal` covers two different worlds: a proposer that considered the facts and declined, and one
        # that could not start at all. Losing that distinction hides a fixable configuration error as a quiet round.
        why = str(getattr(proposer, "reason", "") or "")
        return _finish(
            journal,
            directory,
            record,
            outcome="rejected",
            reason=f"no_proposal: {why}" if why else "no_proposal",
            cost=spent,
            trajectories=trajectories,
        )
    refusal = refuse_proposal(proposal, config)
    if refusal is not None:
        return _finish(
            journal, directory, record, outcome="rejected", reason=refusal, proposal=proposal, cost=spent, trajectories=trajectories
        )
    leak = refuse_if_holdout(_pairs_named_by(proposal, cases), cases)
    if leak is not None:
        # Req 5.2: a change a holdout pair taught, or that names one, is refused by name rather than measured.
        return _finish(
            journal,
            directory,
            record,
            outcome="refused_holdout",
            reason=leak.degradation()["detail"],  # type: ignore[arg-type]
            proposal=proposal,
            cost=spent,
            trajectories=trajectories,
        )
    # The sweep's "before" is measured with the unchanged configurations, so what it later reports is what this
    # round flipped and not what was already failing (Req 9.5).
    before_sweep = _sweep_scores(cases, taxonomy, configs, scan_factory, sweep_families, family, k_runs)
    if _over_cap():
        return _finish(
            journal,
            directory,
            record,
            outcome="reverted_cost",
            reason="cost_cap_exceeded",
            proposal=proposal,
            cost=spent,
            trajectories=trajectories,
        )
    snapshot = DirectorySnapshot.of(configs_dir / family)
    apply_proposal(proposal, configs_dir / family)
    version = str(int(config.version) + 1) if config.version.isdigit() else f"{config.version}+1"
    try:
        after_config = load_family_configs(configs_dir, taxonomy)[family]
        after_scan = scan_factory(after_config)
        after_train = _score(batch, after_scan, family)
        after_hold = _score(holdout, after_scan, family)
        for score in after_train + after_hold:
            archive.record(family, version, score)  # type: ignore[attr-defined]
        if _over_cap():
            snapshot.restore()
            return _finish(
                journal,
                directory,
                record,
                outcome="reverted_cost",
                reason="cost_cap_exceeded",
                proposal=proposal,
                cost=spent,
                scores=after_train + after_hold,
                trajectories=trajectories,
            )
        after_sweep = _sweep_scores(cases, taxonomy, configs, scan_factory, sweep_families, family, k_runs)
        sweep, flipped_unpredicted = _negative_flips(before_sweep, after_sweep)
        train_delta = _delta(before_train, after_train)
        holdout_delta = _delta(before_hold, after_hold)
        flipped = _flipped(before_train + before_hold, after_train + after_hold)
        train_moves = _moves(before_train, after_train)
        holdout_moves = _moves(before_hold, after_hold)
        attribution = Attribution(
            flipped_predicted=len(flipped),
            flipped_unpredicted=len(flipped_unpredicted),
            precision=len(flipped) / (len(flipped) + len(flipped_unpredicted)) if flipped or flipped_unpredicted else 0.0,
        )
        if _over_cap():
            snapshot.restore()
            return _finish(
                journal,
                directory,
                record,
                outcome="reverted_cost",
                reason="cost_cap_exceeded",
                proposal=proposal,
                cost=spent,
                scores=after_train + after_hold,
                trajectories=trajectories,
            )
        verdict = decide(target=family, train_delta=train_delta, holdout_delta=holdout_delta, sweep=sweep, floors=floors)  # type: ignore[arg-type]
        if not verdict.accepted:
            snapshot.restore()
            return _finish(
                journal,
                directory,
                record,
                outcome="rejected",
                reason=verdict.reason,
                proposal=proposal,
                cost=spent,
                train_delta=train_delta,
                holdout_delta=holdout_delta,
                sweep=sweep,
                attribution=attribution,
                moves=(train_moves, holdout_moves),
                flipped=flipped,
                unpredicted=flipped_unpredicted,
                scores=after_train + after_hold,
                trajectories=trajectories,
            )
        bump_version(configs_dir / family, version)
        return _finish(
            journal,
            directory,
            record,
            outcome="accepted",
            reason=verdict.reason,
            proposal=proposal,
            cost=spent,
            train_delta=train_delta,
            holdout_delta=holdout_delta,
            sweep=sweep,
            attribution=attribution,
            moves=(train_moves, holdout_moves),
            flipped=flipped,
            unpredicted=flipped_unpredicted,
            scores=after_train + after_hold,
            version=version,
            trajectories=trajectories,
        )
    except Exception as exc:
        # A stage that raises has already spent money and already changed the tree. Both facts belong in the
        # journal before the exception leaves, or the next round starts from a state nothing describes.
        snapshot.restore()
        _finish(
            journal,
            directory,
            record,
            outcome="reverted",
            reason=f"stage_failed: {type(exc).__name__}",
            proposal=proposal,
            cost=spent,
            trajectories=trajectories,
        )
        raise


def _pairs_named_by(proposal: Proposal, cases: Sequence[PairCase]) -> tuple[str, ...]:
    """Every corpus pair this proposal names, in its predictions or in the file it writes.

    A memory entry that quotes a held-out pair is the loop learning the answer instead of the shape, and it looks
    exactly like a legitimate hard negative until the holdout number is read as if it meant something."""
    haystack = "\n".join([*proposal.predicted_affected, *proposal.predicted_at_risk, *proposal.change.values()])
    # Substring first, regex only for the handful that survive it: the corpus is a few hundred rows and a round
    # runs this once, but a per-round sweep of one regex per row is the kind of thing that stops being free.
    named = [
        name
        for case in cases
        if (name := str(getattr(case, "name", ""))) and name in haystack and re.search(rf"(?<![\w-]){re.escape(name)}(?![\w-])", haystack)
    ]
    return tuple(sorted(set(named)))


def _sweep_scores(
    cases: Sequence[PairCase],
    taxonomy: FamilyTaxonomy,
    configs: Mapping[str, FamilyConfig],
    scan_factory: Callable[[FamilyConfig], Scan],
    families: Sequence[str],
    target: str,
    k_runs: int,
) -> dict[str, dict[str, str]]:
    """Every other family's held-out pairs, family by family, as `{family: {pair: outcome}}`.

    Called once before the change and once after it. Scoring both sides is the only way to say which pairs *this*
    round broke: on a real corpus most pairs are failing already, and counting failures would reject every round
    for damage it did not do (Req 9.5). Unscorable rows are dropped here rather than counted as failures (Req 4.1).
    """
    outcomes: dict[str, dict[str, str]] = {}
    for name in families:
        if name == target or name not in configs:
            continue
        rows = [case for case in cases if case.split == "holdout" and _family_of(case, taxonomy) == name]
        scan = scan_factory(configs[name])
        scored = [score_case(case, scan, taxonomy=taxonomy, runs=k_runs, family=name) for case in rows]
        outcomes[name] = {item.pair: item.outcome for item in scored if item.outcome != "unscorable"}
    return outcomes


def _negative_flips(before: Mapping[str, Mapping[str, str]], after: Mapping[str, Mapping[str, str]]) -> tuple[dict[str, int], list[str]]:
    """Pairs that were right before this round and are not right after it, per family and by name."""
    flips: dict[str, int] = {}
    broken: list[str] = []
    for name, was in before.items():
        now = after.get(name, {})
        lost = sorted(pair for pair, outcome in was.items() if outcome == "pair_correct" and now.get(pair) != "pair_correct")
        flips[name] = len(lost)
        broken.extend(lost)
    return flips, broken


def _delta(before: Sequence[PairFamilyScore], after: Sequence[PairFamilyScore]) -> float:
    """The change in how many pairs came out right, as a fraction of the pairs that could be scored."""
    scorable = [item for item in before if item.outcome != "unscorable"]
    if not scorable:
        return 0.0
    was = sum(1 for item in before if item.outcome == "pair_correct")
    now = sum(1 for item in after if item.outcome == "pair_correct")
    return (now - was) / len(scorable)


def _moves(before: Sequence[PairFamilyScore], after: Sequence[PairFamilyScore]) -> tuple[int, int]:
    """(pairs that became correct, pairs that stopped being correct) — what the sign test is run over."""
    was = {item.pair: item.outcome for item in before if item.outcome != "unscorable"}
    better = worse = 0
    for item in after:
        previous = was.get(item.pair)
        if previous is None or item.outcome == "unscorable":
            continue
        if previous != "pair_correct" and item.outcome == "pair_correct":
            better += 1
        elif previous == "pair_correct" and item.outcome != "pair_correct":
            worse += 1
    return better, worse


def _flipped(before: Sequence[PairFamilyScore], after: Sequence[PairFamilyScore]) -> list[str]:
    """Pairs this round turned right, by name and in a stable order."""
    was = {item.pair: item.outcome for item in before}
    return sorted(item.pair for item in after if item.outcome == "pair_correct" and was.get(item.pair) not in {"pair_correct", None})


def _round_record(
    round_number: int, family: str, proposal: Proposal | None, taxonomy: FamilyTaxonomy, config: FamilyConfig
) -> dict[str, object]:
    return {
        "round": round_number,
        "family": family,
        "hypothesis": proposal.hypothesis if proposal is not None else "",
        "levers": (proposal.lever,) if proposal is not None else (),
        "predicted_affected": tuple(proposal.predicted_affected) if proposal is not None else (),
        "predicted_at_risk": tuple(proposal.predicted_at_risk) if proposal is not None else (),
        "taxonomy_version": taxonomy.version,
        "config_version": config.version,
    }


def _finish(
    journal: LearningJournal,
    directory: Path,
    base: dict[str, object],
    *,
    outcome: str,
    reason: str,
    proposal: Proposal | None = None,
    cost: float = 0.0,
    train_delta: float = 0.0,
    holdout_delta: float = 0.0,
    sweep: Mapping[str, int] | None = None,
    attribution: Attribution | None = None,
    moves: tuple[tuple[int, int], tuple[int, int]] = ((0, 0), (0, 0)),
    flipped: Sequence[str] = (),
    unpredicted: Sequence[str] = (),
    scores: Sequence[PairFamilyScore] = (),
    version: str | None = None,
    trajectories: Callable[[], Sequence[Mapping[str, object]]] | None = None,
) -> RoundRecord:
    """Write the round directory and journal the outcome. Every outcome is journalled, not just the good ones."""
    from ..redaction import redact_secrets

    record = RoundRecord(
        **base,  # type: ignore[arg-type]
        outcome=outcome,
        reason=reason,
        target_train_delta=train_delta,
        target_holdout_delta=holdout_delta,
        sweep=dict(sweep or {}),
        attribution=attribution or Attribution(),
        cost_usd=cost,
        train_better=moves[0][0],
        train_worse=moves[0][1],
        holdout_better=moves[1][0],
        holdout_worse=moves[1][1],
    )
    if version is not None:
        record = RoundRecord(**{**record.__dict__, "config_version": version})
    directory.mkdir(parents=True, exist_ok=True)
    if proposal is not None:
        (directory / "proposal.json").write_text(
            redact_secrets(json.dumps(proposal.to_dict(), indent=2, sort_keys=True)) + "\n",
            encoding="utf-8",
        )
    (directory / "scores.json").write_text(
        json.dumps([{"pair": item.pair, "family": item.family, "outcome": item.outcome} for item in scores], indent=2, sort_keys=True)
        + "\n",
        encoding="utf-8",
    )
    (directory / "attribution.json").write_text(
        json.dumps({"flipped_predicted": list(flipped), "flipped_unpredicted": list(unpredicted)}, indent=2, sort_keys=True) + "\n",
        encoding="utf-8",
    )
    rows = list(trajectories() if trajectories is not None else ())
    (directory / "trajectories.jsonl").write_text(
        "".join(redact_secrets(json.dumps(row, sort_keys=True)) + "\n" for row in rows), encoding="utf-8"
    )
    journal.append(record)  # type: ignore[attr-defined]
    return record


__all__ = [
    "DEFAULT_K_RUNS",
    "MIN_K_RUNS",
    "run_learning_round",
    "DEFAULT_SLICES",
    "NON_GATING_FAMILIES",
    "BaselineReport",
    "NoiseFloor",
    "Scan",
    "compare_baselines",
    "load_noise_floors",
    "run_baseline",
    "score_case",
]