"""342-3 세부 유역 저장본(부록 4 R15) — 열쇠가 같으면 다시 나누지 않음.

- 열쇠 = 관 목록 · 노선(평면 · 종단 Z) · 분석 산출물 · 강우표 · 구조물 정의 자국.
- 같은 열쇠 = _build 안 부름 · 관 목록은 사본 · 무엇이든 바뀌면 다시 셈.
- [저장] 뒤 파일 한 벌 — 서버를 다시 켜도(메모리 비움) GET 열쇠로 읽힘.
"""

import os
from pathlib import Path
from types import SimpleNamespace

import pytest

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
from common_util.common_util_drainage_pipes import PipePoint
from common_util.common_util_route_geometry import RouteVertex


@pytest.fixture
def setup(tmp_path, monkeypatch):
    monkeypatch.setattr(basins, "drainage_dir", lambda stored: tmp_path)
    basins._DETAIL_CACHE.clear()
    calls = SimpleNamespace(count=0)

    def build(stored_path, context, points):
        calls.count += 1
        chainages = [p.chainage_m for p in points] if points else [50.0]
        return DrainageDetail(), [PipePoint(chainage_m=c, source="stream") for c in chainages]

    monkeypatch.setattr(basins, "_build", build)
    (tmp_path / "03_road_routing.npz").write_bytes(b"grid")
    context = DrainageContext(
        stored_path="x",
        project_root=Path("."),
        vertices=[RouteVertex(0.0, 0.0, 100.0, 0.0), RouteVertex(300.0, 0.0, 90.0, 300.0)],
    )
    return tmp_path, context, calls


def test_same_key_reuses_and_copies(setup):
    _, context, calls = setup
    points = [PipePoint(chainage_m=120.0, source="user")]
    _, first = basins._build_cached(context, points)
    first[0].x = 999.0  # 저장이 좌표를 채워도 저장본은 그대로
    _, second = basins._build_cached(context, points)
    assert calls.count == 1
    assert second[0].x is None


def test_any_input_change_recomputes(setup):
    tmp_path, context, calls = setup
    points = [PipePoint(chainage_m=120.0, source="user")]
    basins._build_cached(context, points)
    basins._build_cached(context, [PipePoint(chainage_m=121.0, source="user")])  # 관 자리
    context.vertices[1].z = 91.0  # 계획고(종단 Z) → 관 깊이
    basins._build_cached(context, points)
    routing = tmp_path / "03_road_routing.npz"
    routing.write_bytes(b"grid-2")  # 분석 다시 돎
    os.utime(routing, ns=(1, 1))
    basins._build_cached(context, points)
    assert calls.count == 4


def test_saved_file_survives_restart(setup):
    tmp_path, context, calls = setup
    stored = [PipePoint(chainage_m=120.0, source="stream")]
    detail, carried = basins._build(context.stored_path, context, stored)
    basins._save_detail_cache(context, stored, detail, carried)
    assert (tmp_path / basins.DETAIL_CACHE_FILENAME).exists()
    basins._DETAIL_CACHE.clear()  # 서버 다시 켬
    _, again = basins._build_cached(context, stored)
    assert calls.count == 1
    assert [p.chainage_m for p in again] == [120.0]