"""512-6(요구 326-6) 노선 [저장] 뒤 새로 연 B05 = 저장된 옛 유역 그림 + 낡음.

- 낡은 분석(노선 지문 다름)이면 마지막 [저장]의 세부 유역 저장본(`04_detail_cache.pkl`)으로
  옛 유역 · 옛 노선선을 돌려줌 · 관 자리만 지금 노선 위 · 저장본 없으면 관 자리만(옛 꼴).
- 화면은 열 때 그림이 없으니 그 답을 그대로 그림 + 낡음 점([업데이트] 로만 바꿈 · test_512_2).
"""

import pickle
from pathlib import Path
from uuid import uuid4

from pyproj import Transformer

from B04_PreProcess import B04_PreProcess_Router_Basins as basins
from common_util.common_util_drainage_context import DrainageContext
from common_util.common_util_drainage_detail import DrainageDetail, WatershedBasin
from common_util.common_util_route_geometry import RouteVertex

CRS = "EPSG:5186"
TO = Transformer.from_crs(CRS, "EPSG:4326", always_xy=True)


def _context(tmp_path: Path, monkeypatch, shift: float) -> DrainageContext:
    monkeypatch.setattr(basins, "drainage_dir", lambda _stored: tmp_path)
    vertices = [
        RouteVertex(200000.0 + shift, 500000.0, 100.0, 0.0),
        RouteVertex(200300.0 + shift, 500000.0, 90.0, 300.0),
    ]
    return DrainageContext(
        stored_path="x",
        project_root=tmp_path,
        vertices=vertices,
        crs=CRS,
        to_lonlat=lambda x, y: TO.transform(x, y),
    )


def test_저장본_있으면_옛_그림과_옛_노선(tmp_path, monkeypatch):
    old = DrainageDetail(
        route_lonlat=[
            list(TO.transform(200000.0, 500000.0)),
            list(TO.transform(200300.0, 500000.0)),
        ],
        basins=[WatershedBasin(index=1, chainage_m=120.0, outlet_x=200120.0, outlet_y=500000.0)],
    )
    with (tmp_path / basins.DETAIL_CACHE_FILENAME).open("wb") as file:
        pickle.dump({"key": "옛", "value": (old, [])}, file)
    context = _context(tmp_path, monkeypatch, shift=17.0)  # 노선 17 m 옮김
    points = [basins.PipePoint(chainage_m=150.0, source="user")]
    detail = basins._build_stale(context, points)
    assert [basin.chainage_m for basin in detail.basins] == [120.0]
    assert detail.pipe_candidates == []
    assert abs(detail.pipes[0].x - 200167.0) < 1e-6  # 관 = 지금 노선 위
    payload = basins._payload(uuid4(), context, detail, points, True, stale=True)
    assert payload["stale"] and len(payload["basins"]) == 1
    xy = payload["route_xy"]
    assert abs(xy[0][0] - 200000.0) < 0.01 and abs(xy[1][0] - 200300.0) < 0.01  # 옛 노선


def test_저장본_없으면_관_자리만(tmp_path, monkeypatch):
    context = _context(tmp_path, monkeypatch, shift=17.0)
    points = [basins.PipePoint(chainage_m=150.0, source="user")]
    detail = basins._build_stale(context, points)
    assert detail.basins == []
    payload = basins._payload(uuid4(), context, detail, points, True, stale=True)
    assert abs(payload["route_xy"][0][0] - 200017.0) < 0.01  # 지금 노선


def test_깨진_저장본은_없음과_같음(tmp_path, monkeypatch):
    (tmp_path / basins.DETAIL_CACHE_FILENAME).write_bytes(b"broken")
    monkeypatch.setattr(basins, "drainage_dir", lambda _stored: tmp_path)
    assert basins._read_cache_file("x") is None