"""경로 해석 — 우선순위와 오류 메시지."""

import pytest

from nusim.paths import DatasetPaths, nuscenes_root


def _fake_root(tmp_path):
    for d in ("v1.0-trainval", "samples", "maps"):
        (tmp_path / d).mkdir()
    return tmp_path


def test_explicit_wins(tmp_path, monkeypatch):
    root = _fake_root(tmp_path)
    monkeypatch.setenv("NUSCENES_ROOT", "/does/not/exist")
    assert nuscenes_root(root) == root


def test_env_var_used(tmp_path, monkeypatch):
    root = _fake_root(tmp_path)
    monkeypatch.setenv("NUSCENES_ROOT", str(root))
    assert nuscenes_root() == root


def test_missing_root_lists_what_it_tried(tmp_path, monkeypatch):
    monkeypatch.setenv("NUSCENES_ROOT", str(tmp_path / "nope"))
    monkeypatch.setattr("nusim.paths._ROOT_CANDIDATES", ())
    monkeypatch.setattr("nusim.paths.workspace_root", lambda: tmp_path)
    with pytest.raises(FileNotFoundError) as e:
        nuscenes_root()
    # 사용자가 무엇을 고쳐야 하는지 알 수 있어야 한다
    assert "nope" in str(e.value)
    assert "NUSCENES_ROOT" in str(e.value)


def test_subpaths(tmp_path):
    root = _fake_root(tmp_path)
    d = DatasetPaths(root=root)
    assert d.meta == root / "v1.0-trainval"
    assert d.map_expansion == root / "maps" / "expansion"
    checks = d.check()
    assert checks["meta"][0] is True
    assert checks["can_bus"][0] is False