"""Pure-helper regression tests for the 2026-09-26 offline rectification research.

Fictional inputs only. These cover the research helpers, not production code.
"""
from __future__ import annotations

from datetime import date, timedelta

from scripts.research.offline_research_20260926_lib import (
    NAKSHATRA_SPAN,
    answerable_indices,
    exhaustive_flip_sets,
    flipped_answers,
    nakshatra_lord,
    sample_flip_sets,
    shift_days_per_minute,
    zip_misaligned,
)
from scripts.research.representative_pairs_probe import strict_boundary_windows
from scripts.research.varga_sensitivity_rerun import V1N_FACTORS, factor_table

MEAN_MOON_DEG_PER_DAY = 13.176


def test_shift_per_minute_is_about_one_year_per_degree_not_122_days() -> None:
    venus = shift_days_per_minute(NAKSHATRA_SPAN * 1 + 1.0, MEAN_MOON_DEG_PER_DAY)
    sun = shift_days_per_minute(NAKSHATRA_SPAN * 2 + 1.0, MEAN_MOON_DEG_PER_DAY)
    assert nakshatra_lord(NAKSHATRA_SPAN * 1 + 1.0) == "Venus"
    assert nakshatra_lord(NAKSHATRA_SPAN * 2 + 1.0) == "Sun"
    assert 4.9 < venus < 5.1
    assert 1.45 < sun < 1.55
    # The 2026-09-14 figure (1.1 days) is below the slowest lord at mean speed.
    assert sun > 1.1


def test_flip_sets_are_seeded_and_only_touch_answered_questions() -> None:
    answers = ["yes", None, "no", "yes", None, "no"]
    assert answerable_indices(answers) == [0, 2, 3, 5]
    first = sample_flip_sets(answers, 2, 5, case_id="fictional", radius=10)
    again = sample_flip_sets(answers, 2, 5, case_id="fictional", radius=10)
    assert first == again
    assert all(len(item) == 2 and set(item) <= {0, 2, 3, 5} for item in first)
    assert sample_flip_sets(answers, 5, 3, case_id="fictional", radius=10) == []
    assert len(exhaustive_flip_sets(answers, 2)) == 6
    assert flipped_answers(answers, (0, 2)) == ["no", None, "yes", "yes", None, "no"]


# Unequal spacing, like real dasha periods (equal spacing would make an
# off-by-one zip look like a constant shift).
OFFSETS = (0, 300, 1000, 1200, 2500, 2600)


def test_zip_misalignment_detects_off_by_one_lists() -> None:
    base = [date(2000, 1, 10) + timedelta(days=days) for days in OFFSETS]
    shifted = [item + timedelta(days=20) for item in base]
    assert not zip_misaligned(base, shifted)
    assert zip_misaligned(base[1:], shifted)


def test_strict_gate_drops_year_straddle_and_realigns() -> None:
    left = [date(1999, 12, 28), date(2003, 5, 1)]
    right = [date(2000, 1, 4), date(2003, 5, 8)]
    assert strict_boundary_windows(left, right, min_days=45) == []
    base = [date(2000, 3, 1) + timedelta(days=days) for days in OFFSETS]
    later = [item + timedelta(days=10) for item in base]
    assert strict_boundary_windows(base, later[1:], min_days=45) == []
    far = [item + timedelta(days=60) for item in base]
    assert len(strict_boundary_windows(base, far, min_days=45)) == 2 * len(OFFSETS)


def test_v1_saturates_on_wide_windows_and_v1n_keeps_mean_one() -> None:
    table = factor_table()
    assert set(table["30"].values()) == {1.0}
    assert set(table["60"].values()) == {1.0}
    assert table["10"]["D2"] < 1.0
    assert abs(sum(V1N_FACTORS.values()) / len(V1N_FACTORS) - 1.0) < 1e-4
    assert V1N_FACTORS["D30"] > V1N_FACTORS["D2"]