"""Unit tests for the fiction-wing probe harness's pure helpers.

Only the network-free helpers are covered here; the live retrieval paths
(search_library / reference_knowledge) are exercised by running the harness
against a live Worldtree index, not by pytest.
"""
import sys
from pathlib import Path

_DIAG = Path(__file__).resolve().parent.parent / "docs" / "diagnostics"
sys.path.insert(0, str(_DIAG))

from fiction_wing_probe import _on_target  # noqa: E402

CURLY = "’"  # noqa: RUF001 - the b170 extraction's default apostrophe


def test_on_target_matches_curly_apostrophe_excerpt():
    # Excerpt stores the curly apostrophe; keyword is ASCII. Must still match.
    excerpt = f"Mr. Darcy{CURLY}s letter to Elizabeth explains his conduct."
    assert _on_target(excerpt, ["darcy's letter"])


def test_on_target_matches_ascii_excerpt_against_curly_keyword():
    # Symmetric: ASCII excerpt, curly-quoted keyword. Fold both sides.
    excerpt = "Mrs. Gardiner's letter arrived the next morning."
    assert _on_target(excerpt, [f"gardiner{CURLY}s letter"])


def test_on_target_still_rejects_absent_subject():
    # Negative control: folding must not make unrelated excerpts match.
    excerpt = "A passage about dungeons, crawlers, and monsters."
    assert not _on_target(excerpt, ["darcy's letter"])