from pathlib import Path

import pytest

from l4d2host.paths import get_left4me_root, overlay_path, validate_overlay_ref


def test_get_left4me_root_defaults_to_var_lib_left4me(monkeypatch: pytest.MonkeyPatch) -> None:
    monkeypatch.delenv("LEFT4ME_ROOT", raising=False)

    assert get_left4me_root() == Path("/var/lib/left4me")


def test_get_left4me_root_uses_env(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
    monkeypatch.setenv("LEFT4ME_ROOT", str(tmp_path))

    assert get_left4me_root() == tmp_path


def test_get_left4me_root_rejects_relative_env(monkeypatch: pytest.MonkeyPatch) -> None:
    monkeypatch.setenv("LEFT4ME_ROOT", "var/lib/left4me")

    with pytest.raises(ValueError):
        get_left4me_root()


@pytest.mark.parametrize("raw", ["", "   "])
def test_get_left4me_root_rejects_empty_env(monkeypatch: pytest.MonkeyPatch, raw: str) -> None:
    monkeypatch.setenv("LEFT4ME_ROOT", raw)

    with pytest.raises(ValueError):
        get_left4me_root()


@pytest.mark.parametrize("ref", ["standard", "competitive/base", "users/42/custom"])
def test_validate_overlay_ref_accepts_safe_refs(ref: str) -> None:
    assert validate_overlay_ref(ref) == ref


@pytest.mark.parametrize(
    "ref",
    ["", "/tmp/bad", "../bad", "bad/../evil", "bad//evil", " bad", "bad ", ".", "bad/./evil"],
)
def test_validate_overlay_ref_rejects_unsafe_refs(ref: str) -> None:
    with pytest.raises(ValueError):
        validate_overlay_ref(ref)


def test_overlay_path_resolves_under_root(tmp_path: Path) -> None:
    assert overlay_path("standard", root=tmp_path) == tmp_path / "overlays" / "standard"


def test_overlay_path_rejects_symlink_escape(tmp_path: Path) -> None:
    outside = tmp_path / "outside"
    outside.mkdir()
    overlays = tmp_path / "overlays"
    overlays.mkdir()
    (overlays / "escape").symlink_to(outside)

    with pytest.raises(ValueError):
        overlay_path("escape", root=tmp_path)