llm-ingestion-okf/tests/test_propose_segments.py

"""The proposer: it proposes, a human adjudicates, and it never pretends otherwise.

The research is explicit about why this tool exists and about what it may not
claim. Topic 2 measured that the OKF reference agent splits on **what a thing
is** -- four semantic gates that need a model this run path does not have --
while a handful of MECHANICAL rules port today. Topic 1b measured that heading
derivation is inert on most of the K2 corpus: 23 of 33 PDFs carry no outline at
all and 95 % of the outline entries that exist are CAD export metadata, so the
scoreable denominator is ONE document. A rule validated on n=1 is not validated.

So the tool marks every decision `PROPOSED` and nothing else. The distinction
is the whole design: a proposal a human has not looked at must never be
replayable as an adjudication, because replay is exactly what the run path does
with a plan, deterministically and forever.

It lives outside `src/`, so it never enters a wheel (`tests/test_packaging.py`
enforces that) and no consumer's install surface changes because it exists.
"""

from __future__ import annotations

import json
import socket
import sys
from pathlib import Path

import pytest

from llm_ingestion_okf.segmentation import parse_segmentation_plan

sys.path.insert(0, str(Path(__file__).resolve().parents[1] / "tools"))

import okf_propose_segments  # noqa: E402

DOCUMENT = """# N500 Vegbygging

Innledende tekst om vegbygging og dens omfang.

## 3.1 Brannkonsept

Krav til seksjonering av bygget over flere etasjer.

## 3.2 Roemning

To uavhengige roemningsveier fra hver branncelle.

## Og

## 3.3 Baereevne

Hovedbaeresystemet skal ha R60 dokumentert baereevne.
"""


#: The golden fixture's document. It carries a BARE-INTEGER ascending run of
#: three (`1`, `2`, `3`), which today's rules do not match at all -- measured,
#: bare `1` / `1.` / `1)` yield 0 candidates. That is precisely why the golden
#: is taken over THIS text and not over `DOCUMENT`: `DOCUMENT` has no
#: bare-integer line, so a golden over it would stay byte-identical even if the
#: outline rule were accidentally defaulted ON, and the guard would be a trap
#: written down but never able to fire. The ATX heading and the dotted heading
#: are here so the shipping rules fire too, and the golden pins their output as
#: well as the outline rule's absence.
OUTLINE_DOCUMENT = """# Stange skole -- teknisk grunnlag

Innledende tekst som gir dokumentet en kropp foer kapitlene begynner.

1 Innledning

Bakgrunnen for prosjektet og omfanget av arbeidet.

2 Krav

Krav til seksjonering av bygget over flere etasjer.

3 Gjennomfoering

Framdrift, faser og overlevering av bygget.

1.1 Brannkonsept

To uavhengige roemningsveier fra hver branncelle.
"""

#: Frozen in the golden's bytes. An explicit argument because the artifact
#: carries it verbatim, and a wall-clock default would make the golden
#: unreproducible by construction.
GOLDEN_PROPOSED_AT = "2026-09-03T00:00:00Z"


def write(tmp_path: Path, text: str = DOCUMENT, name: str = "n500.md") -> Path:
    path = tmp_path / name
    path.write_text(text, encoding="utf-8", newline="")
    return path


def propose(tmp_path: Path, **kwargs: object) -> dict:
    source = kwargs.pop("source", None) or write(tmp_path)
    out = tmp_path / "plan.json"
    code = okf_propose_segments.main([str(source), "--out", str(out)])
    assert code == 0, f"proposer exited {code}"
    return json.loads(out.read_text(encoding="utf-8"))


# --- the artifact is a valid plan -----------------------------------------


def test_the_emitted_artifact_parses_as_a_segmentation_plan(tmp_path: Path) -> None:
    plan = parse_segmentation_plan(propose(tmp_path))
    assert plan.entries


def test_it_carries_its_provenance(tmp_path: Path) -> None:
    payload = propose(tmp_path)
    assert payload["source_sha256"]
    assert payload["extractor_id"]
    assert payload["extractor_version"]
    assert payload["proposed_by"].startswith("okf-propose-segments")


def test_the_source_hash_is_the_hash_of_the_bytes_it_read(tmp_path: Path) -> None:
    import hashlib

    source = write(tmp_path)
    payload = propose(tmp_path, source=source)
    assert payload["source_sha256"] == hashlib.sha256(source.read_bytes()).hexdigest()


# --- PROPOSED, never adjudicated ------------------------------------------


def test_every_entry_is_marked_proposed(tmp_path: Path) -> None:
    payload = propose(tmp_path)
    assert payload["entries"]
    for entry in payload["entries"]:
        assert okf_propose_segments.PROPOSED_MARKER in entry["derived"]


def test_no_entry_claims_to_be_adjudicated(tmp_path: Path) -> None:
    payload = propose(tmp_path)
    assert payload["adjudicated"] is False
    for entry in payload["entries"]:
        assert "adjudicated" not in entry


def test_every_entry_names_the_rule_that_proposed_it(tmp_path: Path) -> None:
    # Per-decision provenance. A proposal an operator cannot trace to a rule is
    # one they can only accept or reject wholesale.
    for entry in propose(tmp_path)["entries"]:
        rules = [name for name in entry["derived"] if name.startswith("rule:")]
        assert len(rules) == 1
        assert rules[0] in okf_propose_segments.RULE_NAMES


# --- the mechanical rules that actually ported -----------------------------


def test_a_heading_of_only_stop_words_is_not_a_boundary(tmp_path: Path) -> None:
    # "Og" is a stop word. Without the gate it would open a segment of its own.
    titles = [entry["title"] for entry in propose(tmp_path)["entries"]]
    assert "Og" not in titles
    assert any("Brannkonsept" in title for title in titles)


def test_a_heading_with_no_body_proposes_nothing(tmp_path: Path) -> None:
    """The orphan check, observed through the status now that a zero-entry plan
    is no longer written: proposing nothing and writing nothing are the same
    outcome, and it is distinct from failing."""
    out = tmp_path / "orphans.json"
    source = write(tmp_path, "# Tom\n\n## Ogsaa tom\n")
    assert okf_propose_segments.main([str(source), "--out", str(out)]) == 1
    assert not out.exists()


def test_the_spans_it_proposes_are_slices_of_the_text_it_read(tmp_path: Path) -> None:
    from llm_ingestion_okf.extract import extract_text

    source = write(tmp_path)
    payload = propose(tmp_path, source=source)
    text = extract_text(source.name, source.read_bytes())
    for entry in payload["entries"]:
        start, end = entry["span"]
        assert text[start:end].strip()


def test_every_entry_carries_an_anchor_quoting_its_own_span(tmp_path: Path) -> None:
    """Written at proposal time, when text and offsets are known to agree.

    Reconstructed later it would quote whatever the extraction had already
    become, which is precisely the drift the anchor exists to survive.
    """
    from llm_ingestion_okf.extract import extract_text

    source = write(tmp_path)
    payload = propose(tmp_path, source=source)
    text = extract_text(source.name, source.read_bytes())
    assert payload["entries"]
    for entry in payload["entries"]:
        start, end = entry["span"]
        anchor = entry["anchor"]
        assert anchor["quote"] == text[start:end]
        assert text[start - len(anchor["prefix"]) : start] == anchor["prefix"]
        assert text[end : end + len(anchor["suffix"])] == anchor["suffix"]


def test_a_proposed_plan_survives_a_shift_of_the_text_it_was_made_against(
    tmp_path: Path,
) -> None:
    """The round trip the anchor exists for, measured end to end.

    Prepend a paragraph -- exactly the benign edit that leaves every offset
    short -- and every body must still be the text the proposer quoted. Before
    anchors this cut each segment early and landed on real prose, with nothing
    anywhere able to tell.
    """
    from llm_ingestion_okf.extract import extract_text
    from llm_ingestion_okf.segmentation import slice_segments

    source = write(tmp_path)
    plan = parse_segmentation_plan(propose(tmp_path, source=source))
    text = extract_text(source.name, source.read_bytes())
    quoted = [text[start:end] for start, end in (item.span for item in plan.entries)]

    shifted = "Et nytt avsnitt foran alt annet.\n\n" + text
    assert [body for _, body in slice_segments(shifted, plan)] == quoted


def test_the_paths_it_proposes_are_unique_and_hierarchical(tmp_path: Path) -> None:
    plan = parse_segmentation_plan(propose(tmp_path))
    paths = [entry.path for entry in plan.entries]
    assert len(paths) == len(set(paths))
    assert any("/" in path for path in paths)


# --- it does not reach the network ----------------------------------------


def test_it_makes_no_network_call(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
    def refuse(*args: object, **kwargs: object) -> None:
        raise AssertionError("the proposer opened a socket")

    monkeypatch.setattr(socket, "socket", refuse)
    monkeypatch.setattr(socket, "create_connection", refuse)
    parse_segmentation_plan(propose(tmp_path))


def test_the_socket_guard_can_actually_fire(monkeypatch: pytest.MonkeyPatch) -> None:
    # The known-positive control. Without it, a guard that patched the wrong
    # name would make "no network call" a statement about nothing.
    def refuse(*args: object, **kwargs: object) -> None:
        raise AssertionError("the proposer opened a socket")

    monkeypatch.setattr(socket, "socket", refuse)
    with pytest.raises(AssertionError, match="opened a socket"):
        socket.socket()


# --- failure is loud ------------------------------------------------------


def test_a_missing_source_exits_two_and_says_so(
    tmp_path: Path, capsys: pytest.CaptureFixture[str]
) -> None:
    code = okf_propose_segments.main([str(tmp_path / "absent.md"), "--out", str(tmp_path / "o")])
    assert code == 2
    assert "okf-propose-segments" in capsys.readouterr().err


def test_an_unknown_file_type_exits_two(tmp_path: Path, capsys: pytest.CaptureFixture[str]) -> None:
    source = write(tmp_path, "body\n", name="thing.unknown")
    code = okf_propose_segments.main([str(source), "--out", str(tmp_path / "o")])
    assert code == 2
    assert "okf-propose-segments" in capsys.readouterr().err


# --- the per-document scope a multi-document corpus needs ------------------


def test_a_path_prefix_scopes_every_entry_under_one_directory(tmp_path: Path) -> None:
    """Measured on the K2 corpus, 2026-09-03: 39 documents proposed 618 entries
    under 601 distinct paths -- **17 paths were claimed by two documents each**.
    Every one of them would hit Door B's collision gate, and the gate refuses
    per DOCUMENT, so those documents would land as coded rejections instead of
    concepts. Section numbering is document-local (`1 Innledning` is in most of
    them), so the collision is structural rather than unlucky.

    The scope is an argument and not something this tool invents: the proposer
    sees one document and has no way of knowing what else is in the bundle, so
    the caller who does supplies the prefix.
    """
    out = tmp_path / "plan.json"
    assert (
        okf_propose_segments.main(
            [str(write(tmp_path)), "--out", str(out), "--path-prefix", "Del II Bilag 3.1"]
        )
        == 0
    )
    payload = json.loads(out.read_text(encoding="utf-8"))
    assert payload["entries"]
    for entry in payload["entries"]:
        assert entry["path"].startswith("del-ii-bilag-3-1/")
    # Still a valid plan: the prefix passes the same path grammar as any other
    # component, rather than being spliced in behind the validator's back.
    assert parse_segmentation_plan(payload).entries


def test_without_a_prefix_the_artifact_is_byte_identical(tmp_path: Path) -> None:
    """Additive. Every plan already produced stays exactly what it was."""
    first = tmp_path / "a.json"
    second = tmp_path / "b.json"
    source = write(tmp_path)
    okf_propose_segments.main([str(source), "--out", str(first)])
    okf_propose_segments.main([str(source), "--out", str(second), "--path-prefix", ""])
    assert first.read_bytes() == second.read_bytes()


def test_a_prefix_that_reduces_to_nothing_is_refused(tmp_path: Path) -> None:
    """A prefix of punctuation would otherwise become an empty component and
    silently produce the unscoped paths the caller asked to avoid."""
    code = okf_propose_segments.main(
        [str(write(tmp_path)), "--out", str(tmp_path / "p.json"), "--path-prefix", "###"]
    )
    assert code == 2
    assert not (tmp_path / "p.json").exists()


# --- nothing to propose is an outcome, and it is not an artifact -----------


def test_a_document_with_no_proposable_structure_writes_no_artifact(tmp_path: Path) -> None:
    """Measured on the K2 corpus 2026-09-03: 11 of 39 documents proposed zero
    segments -- overwhelmingly PDFs with no declared structure, which Topic 1b
    already measured at 23 of 33.

    An empty artifact is not a plan a run can replay: `process_inbox` refuses
    one by design, because an empty plan would persist nothing for a document
    that was dropped. So the only use a zero-entry file has is to fail a run
    later, and writing it converts "this document proposes no split" into "this
    corpus cannot be built". It gets its own exit status instead: distinct from
    2, which means the tool could not do its job at all.
    """
    flat = write(tmp_path, "Loepende tekst uten overskrifter i det hele tatt.\n", name="flat.md")
    out = tmp_path / "flat.json"
    assert okf_propose_segments.main([str(flat), "--out", str(out)]) == 1
    assert not out.exists()


def test_nothing_to_propose_is_not_reported_as_a_failure(
    tmp_path: Path, capsys: pytest.CaptureFixture[str]
) -> None:
    """The two outcomes must be distinguishable by a driver reading the status:
    one means "this document lands as one flat concept", the other means "stop"."""
    flat = write(tmp_path, "Loepende tekst uten overskrifter i det hele tatt.\n", name="flat.md")
    assert okf_propose_segments.main([str(flat), "--out", str(tmp_path / "f.json")]) == 1
    nothing = capsys.readouterr().err
    assert "FAILED" not in nothing
    assert "nothing to propose" in nothing.lower()

    assert (
        okf_propose_segments.main([str(tmp_path / "absent.md"), "--out", str(tmp_path / "a.json")])
        == 2
    )
    assert "FAILED" in capsys.readouterr().err


# --- Arm C: the size-driven subdivision -----------------------------------
#
# Arm C is NOT defined in `docs/2026-09-02-k3-k4-k5-metode.md` -- that file
# contains no occurrence of the word at all -- so the definition these tests
# pin was written for order 20260904T145630Z and is marked as such wherever it
# is reported: Arm B's mechanical rules, plus ONE deterministic rule that
# subdivides any proposed span longer than a declared cap at the nearest
# paragraph boundary at or before it, the whole document counting as one span
# when the rules find no boundary at all.
#
# One rule and not two, on purpose. The two failure modes the K2 rebuild
# measured -- a document with no outline (Bilag 9.1, 217 472 characters) and a
# document whose headings are a table of contents so the trailing segment
# absorbs the body (Bilag 3.1, Bilag 1) -- are the same failure of SIZE, and a
# second rule aimed at each would confound which one moved the number.
#
# What Arm C deliberately does NOT change: the region before the first
# candidate is still covered by no segment. That is a COVERAGE defect the
# baseline's blind rater named, it is real, and fixing it here would put two
# changes behind one measurement.

LONG_PARAGRAPH = ("Krav til seksjonering av bygget over flere etasjer. " * 40).strip()

UNSTRUCTURED = "\n\n".join(f"{LONG_PARAGRAPH} Avsnitt {i}." for i in range(12)) + "\n"

STRUCTURED_WITH_A_LONG_TAIL = (
    "# N500 Vegbygging\n\nInnledende tekst om vegbygging.\n\n"
    "## 3.1 Brannkonsept\n\nKort avsnitt om seksjonering.\n\n"
    "## 3.2 Roemning\n\n" + UNSTRUCTURED
)


def propose_arm_c(tmp_path: Path, text: str, cap: int, name: str = "arm-c.md") -> dict:
    source = write(tmp_path, text, name)
    out = tmp_path / "arm-c-plan.json"
    code = okf_propose_segments.main(
        [str(source), "--out", str(out), "--max-segment-chars", str(cap)]
    )
    assert code == 0, f"proposer exited {code}"
    return json.loads(out.read_text(encoding="utf-8"))


def test_arm_c_off_is_byte_identical_to_the_default(tmp_path: Path) -> None:
    """The cap defaults to 0 = off. The standard profile must not move."""
    source = write(tmp_path, STRUCTURED_WITH_A_LONG_TAIL, "same.md")
    without = tmp_path / "without.json"
    with_zero = tmp_path / "with-zero.json"
    assert okf_propose_segments.main([str(source), "--out", str(without)]) == 0
    assert (
        okf_propose_segments.main(
            [str(source), "--out", str(with_zero), "--max-segment-chars", "0"]
        )
        == 0
    )
    assert without.read_bytes() == with_zero.read_bytes()


def test_a_span_longer_than_the_cap_is_split_into_contiguous_parts(
    tmp_path: Path,
) -> None:
    """The parts must TILE the span they replace: no overlap, no gap.

    Overlap would emit the same unit of knowledge twice, which is the
    `duplicate` category the K3 method counts. A gap would drop text silently.
    """
    plan = propose_arm_c(tmp_path, STRUCTURED_WITH_A_LONG_TAIL, 2000)
    spans = [tuple(entry["span"]) for entry in plan["entries"]]
    assert spans == sorted(spans)
    for (_, first_end), (second_start, _) in zip(spans, spans[1:]):
        assert first_end == second_start, f"{first_end} != {second_start}"


def test_no_proposed_span_exceeds_the_cap(tmp_path: Path) -> None:
    plan = propose_arm_c(tmp_path, STRUCTURED_WITH_A_LONG_TAIL, 2000)
    for entry in plan["entries"]:
        start, end = entry["span"]
        assert end - start <= 2000, f"{entry['path']} is {end - start} chars"


def test_it_cuts_at_a_paragraph_boundary_when_one_is_available(
    tmp_path: Path,
) -> None:
    """A cut mid-sentence splits one unit of knowledge for no reason."""
    plan = propose_arm_c(tmp_path, UNSTRUCTURED, 3000)
    text = UNSTRUCTURED
    for entry in plan["entries"][1:]:
        start = entry["span"][0]
        assert text[start - 2 : start] == "\n\n", repr(text[start - 8 : start + 8])


def test_a_document_with_no_proposable_structure_is_segmented_by_size(
    tmp_path: Path,
) -> None:
    """Bilag 9.1's case: no outline at all, so Arm B proposes nothing."""
    out = tmp_path / "arm-b.json"
    assert okf_propose_segments.main([str(write(tmp_path, UNSTRUCTURED)), "--out", str(out)]) == 1
    assert not out.exists()

    plan = propose_arm_c(tmp_path, UNSTRUCTURED, 3000)
    assert len(plan["entries"]) > 1
    assert plan["entries"][0]["span"][0] == 0
    assert plan["entries"][-1]["span"][1] == len(UNSTRUCTURED)


def test_a_short_unstructured_document_still_proposes_nothing(
    tmp_path: Path, capsys: pytest.CaptureFixture[str]
) -> None:
    """Arm C fires on SIZE. Under the cap there is nothing for it to do, and a
    one-entry plan would only dress the same single concept in a plan file."""
    source = write(tmp_path, "Bare en kort tekst uten noen overskrift.\n", "kort.md")
    out = tmp_path / "kort.json"
    assert (
        okf_propose_segments.main([str(source), "--out", str(out), "--max-segment-chars", "3000"])
        == 1
    )
    assert not out.exists()


def test_every_split_part_names_the_size_rule_and_stays_proposed(
    tmp_path: Path,
) -> None:
    plan = propose_arm_c(tmp_path, UNSTRUCTURED, 3000)
    for entry in plan["entries"]:
        assert entry["derived"][0] == okf_propose_segments.PROPOSED_MARKER
        assert okf_propose_segments.RULE_SIZE_SPLIT in entry["derived"]


def test_a_split_part_keeps_the_rule_that_proposed_its_origin_span(
    tmp_path: Path,
) -> None:
    """Traceability: a part must still name the heading rule it came from."""
    plan = propose_arm_c(tmp_path, STRUCTURED_WITH_A_LONG_TAIL, 2000)
    split = [e for e in plan["entries"] if okf_propose_segments.RULE_SIZE_SPLIT in e["derived"]]
    assert split
    assert all(okf_propose_segments.RULE_HEADING in e["derived"] for e in split)


def test_a_span_under_the_cap_is_left_exactly_as_arm_b_proposed_it(
    tmp_path: Path,
) -> None:
    plan = propose_arm_c(tmp_path, STRUCTURED_WITH_A_LONG_TAIL, 2000)
    untouched = [
        e for e in plan["entries"] if okf_propose_segments.RULE_SIZE_SPLIT not in e["derived"]
    ]
    assert untouched
    for entry in untouched:
        assert entry["derived"] == [
            okf_propose_segments.PROPOSED_MARKER,
            okf_propose_segments.RULE_HEADING,
        ]


def test_split_parts_get_unique_paths(tmp_path: Path) -> None:
    plan = propose_arm_c(tmp_path, STRUCTURED_WITH_A_LONG_TAIL, 2000)
    paths = [entry["path"] for entry in plan["entries"]]
    assert len(paths) == len(set(paths))


def test_the_anchor_quotes_the_part_and_not_the_origin_span(tmp_path: Path) -> None:
    plan = propose_arm_c(tmp_path, UNSTRUCTURED, 3000)
    for entry in plan["entries"]:
        start, end = entry["span"]
        assert entry["anchor"]["quote"] == UNSTRUCTURED[start:end]


def test_a_negative_cap_is_refused(tmp_path: Path, capsys: pytest.CaptureFixture[str]) -> None:
    source = write(tmp_path, UNSTRUCTURED)
    code = okf_propose_segments.main(
        [str(source), "--out", str(tmp_path / "x.json"), "--max-segment-chars", "-1"]
    )
    assert code == 2
    assert "max-segment-chars" in capsys.readouterr().err


def test_an_unbreakable_line_longer_than_the_cap_is_still_cut(
    tmp_path: Path,
) -> None:
    """No paragraph boundary to cut at. The cap still binds -- a part that
    silently exceeded it would make the cap unenforceable exactly where the
    document is hardest."""
    plan = propose_arm_c(tmp_path, "x" * 9000 + "\n", 3000, "unbreakable.md")
    for entry in plan["entries"]:
        start, end = entry["span"]
        assert end - start <= 3000


# --- the default profile, pinned byte for byte ----------------------------
#
# The one guard that can go red on an accidental default-on regression of any
# rule added later. It compares the WHOLE artifact, so a new candidate, a moved
# span, a changed `derived` list or a renamed path all break it.


def test_the_default_artifact_matches_its_committed_golden(tmp_path: Path) -> None:
    """The default profile is a promise to consumers; this is what keeps it.

    The golden transitively pins `observed_extractor_version` too, so a
    converter bump turns this red. That is a legitimate red, not a defect:
    read the diff and decide, per `tests/fixtures/README.md`.
    """
    source = write(tmp_path, OUTLINE_DOCUMENT, "outline.md")
    out = tmp_path / "outline-plan.json"
    assert (
        okf_propose_segments.main(
            [str(source), "--out", str(out), "--proposed-at", GOLDEN_PROPOSED_AT]
        )
        == 0
    )
    golden = Path(__file__).parent / "fixtures" / "propose-golden-default.json"
    assert out.read_bytes() == golden.read_bytes(), (
        "the default artifact diverges from its committed golden bytes"
    )


# --- Arm D: the outline rule ----------------------------------------------
#
# Arm D is NOT defined in `docs/2026-09-02-k3-k4-k5-metode.md` -- that file
# contains no occurrence of the word -- so the definition these tests pin was
# written for the brief of order 20260906T213322Z and is reported as the
# author's, not as a ratified one: Arm B's mechanical rules, plus ONE rule that
# reads the document's OWN numbered outline -- the bare integers `N`, `N.`,
# `N)` that the shipping grammar cannot match because `_NUMBERED` requires a
# dot -- admitted only where the numbers form a maximal ascending run of at
# least a declared length, taking the LAST such run when the outline repeats,
# because a contents listing precedes the body it lists.
#
# EVERY fixture below uses BARE lines with no `#` prefix, and that is load
# bearing rather than stylistic. Measured on today's code: `# 1 Innledning`
# already yields 2 candidates via `_ATX`, and `1.1 Brannkonsept` already yields
# 2 via `_NUMBERED` -- so a fixture using either form would be green before the
# rule exists and would prove nothing. Bare `1` / `1.` / `1)` yield 0.

RUN_OF_THREE_THEN_RUN_OF_TWO = """Forord uten nummerering.

1 Innledning

Bakgrunn for prosjektet og omfanget.

2 Krav

Krav til seksjonering av bygget.

3 Gjennomfoering

Framdrift, faser og overlevering.

1 Vedlegg A

Foerste vedlegg til dokumentet.

2 Vedlegg B

Andre vedlegg til dokumentet.
"""

TWO_MAXIMAL_RUNS = """1 Innledning

Foerste forekomst, i innholdslista.

2 Krav

Andre forekomst, i innholdslista.

3 Gjennomfoering

Tredje forekomst, i innholdslista.

1 Innledning i kroppen

Her begynner selve teksten.

2 Krav i kroppen

Kravene slik de er skrevet ut.

3 Gjennomfoering i kroppen

Gjennomfoeringen slik den er skrevet ut.
"""

ALL_THREE_INTEGER_FORMS = """1 Innledning

Bakgrunn for prosjektet.

2. Krav

Krav til seksjonering.

3) Gjennomfoering

Framdrift og faser.
"""

NUMBER_WITHOUT_A_TITLE = """1 Innledning

Bakgrunn for prosjektet.

2

3 Gjennomfoering

Framdrift og faser.
"""

RUN_NOT_STARTING_AT_ONE = """2 Krav

Krav til seksjonering.

3 Gjennomfoering

Framdrift og faser.

4 Overlevering

Overlevering av bygget.
"""


def outline_titles(runs: list[list[tuple[int, int, str]]]) -> list[list[str]]:
    return [[title for _, _, title in run] for run in runs]


def test_a_run_of_three_fires_and_a_run_of_two_in_the_same_document_does_not() -> None:
    """The paired form, and the pairing is the point.

    A lone "a 2-run must not fire" assertion is true by absence before the rule
    exists and true forever after, so it can never go red. Asserting both in ONE
    document makes the negative half depend on the rule actually running.
    """
    entries = okf_propose_segments.outline_lines(RUN_OF_THREE_THEN_RUN_OF_TWO)
    runs = okf_propose_segments.outline_runs(entries, 3)
    assert outline_titles(runs) == [["Innledning", "Krav", "Gjennomfoering"]]
    # The known-positive control for the same fixture: at a minimum of 2 the
    # second run IS admitted, so its absence above is the gate, not the text.
    relaxed = okf_propose_segments.outline_runs(entries, 2)
    assert outline_titles(relaxed) == [
        ["Innledning", "Krav", "Gjennomfoering"],
        ["Vedlegg A", "Vedlegg B"],
    ]


def test_runs_restart_at_every_new_one_and_the_last_maximal_run_is_the_last() -> None:
    """Two identical runs; the LAST is the body, the first is the contents."""
    entries = okf_propose_segments.outline_lines(TWO_MAXIMAL_RUNS)
    runs = okf_propose_segments.outline_runs(entries, 3)
    assert len(runs) == 2
    assert outline_titles(runs)[-1] == [
        "Innledning i kroppen",
        "Krav i kroppen",
        "Gjennomfoering i kroppen",
    ]
    # And the last run sits later in the document than the first.
    assert runs[-1][0][0] > runs[0][-1][0]


def test_all_three_integer_forms_are_admitted() -> None:
    """`N`, `N.` and `N)` are the same declaration in three typographies."""
    entries = okf_propose_segments.outline_lines(ALL_THREE_INTEGER_FORMS)
    runs = okf_propose_segments.outline_runs(entries, 3)
    assert outline_titles(runs) == [["Innledning", "Krav", "Gjennomfoering"]]


def test_a_number_with_no_title_is_not_a_candidate() -> None:
    """A bare `2` on its own line names no unit of knowledge.

    It also breaks the run, which is the honest outcome: the document did not
    declare a chapter there, so the rule may not invent one.
    """
    entries = okf_propose_segments.outline_lines(NUMBER_WITHOUT_A_TITLE)
    assert [number for _, number, _ in entries] == [1, 3]
    assert okf_propose_segments.outline_runs(entries, 3) == []


def test_a_sequence_not_starting_at_one_is_not_a_run() -> None:
    """A run is anchored at `1`. `2, 3, 4` is page furniture until proven otherwise."""
    entries = okf_propose_segments.outline_lines(RUN_NOT_STARTING_AT_ONE)
    assert [number for _, number, _ in entries] == [2, 3, 4]
    assert okf_propose_segments.outline_runs(entries, 3) == []


def test_a_trailing_page_number_is_stripped_from_an_outline_title() -> None:
    """`Innledning 6` is a contents line; the page number is not part of the title.

    Load-bearing rather than cosmetic: titles become concept paths through
    `_segment_path`, so a page number left on would become part of a filename.
    """
    assert okf_propose_segments._strip_page_number("Innledning 6") == "Innledning"
    assert okf_propose_segments._strip_page_number("Vurdering av restrisiko 25") == (
        "Vurdering av restrisiko"
    )


def test_a_title_that_is_only_digits_is_left_alone_rather_than_emptied() -> None:
    """The negative control for the stripper: it must not eat the whole title.

    Emptying it here would hide junk from the stop-word/junk path that is
    supposed to see it, and an empty stem falls back to `seksjon`, which would
    make junk look like a named section.
    """
    assert okf_propose_segments._strip_page_number("477") == "477"