"""764-1 추천 측점 맞춤 — 덜 나쁜 자리 고를 때 원지반 기울기 늘어남 · 옮긴 거리를 따짐(요구 606-2).

    ./venv/Scripts/python.exe -m pytest resources/tester/test_764_1_snap_grade.py -q

· 가까운 측점 자리가 비탈(기울기 늘어남)이면 다음 측점 자리로 — 옛 순위는 가까운 측점 · 토공을
  앞세워 비탈 자리를 골랐음.
· 모든 자리가 크게 망치면 그중 가장 덜 망치는 자리(곡선 가운데 = 측점은 지킴).
· 판(`ALGO_VERSION`)이 다른 저장본은 꺼내지 않음.
"""

import json
import math

import pytest

from B05_Profile.B05_Profile_Engine_RouteInitial_Station import (
    STATION_M,
    curve_mc_chainages,
    off_station_count,
    snap_curves_to_stations,
)
from B05_Profile.B05_Profile_Engine_RouteInitial_Store import (
    ALGO_VERSION,
    read_stored_any,
    store_dir,
)
from common_util.common_util_route_polyline import build_planned_polyline

RADIUS = 12.0
# MC ≈ 109.5 m — 가까운 측점 100 · 다음 120
POINTS = [(0.0, 0.0), (110.0, 0.0), (230.0, 90.0)]


class _Slope:
    """직접 잼 흉내 — 늘 못 지남(덜 나쁜 자리만 남음) · 곡선 가운데가 x < 112 면 비탈 쪽.

    토공은 비탈 쪽이 더 작게(옛 순위가 비탈을 고르도록 유혹)."""

    def __init__(self, steep: float, flat: float) -> None:
        self.steep, self.flat = steep, flat

    def rise(self, local, reference) -> float:
        arc = local[1:-1]
        return self.steep if sum(x for x, _ in arc) / len(arc) < 112.0 else self.flat

    def judge(self, local, reference):
        return False, (False, 0.0, -1000.0 * self.rise(local, reference))

    def ok(self, local, reference) -> bool:
        return False


def _snap(guard) -> float:
    outline = build_planned_polyline(
        POINTS,
        min_radius_m=RADIUS,
        simplify=False,
        curve_flags=[True] * 3,
        radii=[None, 40.0, None],
    )
    (mc,) = curve_mc_chainages(outline)
    assert abs(mc - 100.0) < abs(mc - 120.0)  # 가까운 측점 = 비탈 쪽
    snapped = snap_curves_to_stations(outline, RADIUS, guard=guard)
    assert snapped is not None and off_station_count(snapped) == 0
    (placed,) = curve_mc_chainages(snapped)
    return round(placed / STATION_M) * STATION_M


def test_less_bad_spot_avoids_slope() -> None:
    """가까운 측점 자리가 기울기를 크게 늘리면 다음 측점 자리."""
    assert _snap(_Slope(steep=0.30, flat=0.0)) == 120.0


def test_all_ruined_takes_least_ruin() -> None:
    """모든 자리가 크게 망치면 그중 가장 덜 망치는 자리 · MC 는 측점에."""
    assert _snap(_Slope(steep=0.20, flat=0.40)) == 100.0
    assert _snap(_Slope(steep=0.40, flat=0.20)) == 120.0


@pytest.mark.parametrize("version, found", [(ALGO_VERSION - 1, False), (ALGO_VERSION, True)])
def test_other_version_not_read(tmp_path, version: int, found: bool) -> None:
    folder = store_dir(tmp_path)
    folder.mkdir(parents=True)
    data = {"version": version, "source": "s", "pool": "p", "request": {}, "result": {}}
    (folder / "k.json").write_text(json.dumps(data), encoding="utf-8")
    got = read_stored_any(tmp_path, "p", lambda source: "k")
    assert (got is not None) is found


def test_ruin_threshold_constants() -> None:
    from B05_Profile.B05_Profile_Engine_RouteInitial_Station import RUIN_GAP_M, RUIN_RISE

    assert RUIN_RISE == pytest.approx(0.05) and math.isclose(RUIN_GAP_M, STATION_M / 2)