from __future__ import annotations

import importlib
import stat
from pathlib import Path

import pytest
from backup_tool.config import Settings

snapshot = importlib.import_module("backup_tool.snapshot")


def settings_for(tmp_path: Path) -> Settings:
    key = tmp_path / "master.key"
    key.write_bytes(b"m6-restore-path-test-master-key-material")
    key.chmod(0o600)
    repositories = tmp_path / "repositories"
    sources = tmp_path / "sources"
    restores = tmp_path / "restores"
    for directory in (repositories, sources, restores):
        directory.mkdir()
    return Settings(
        data_dir=tmp_path,
        database_url=f"sqlite+aiosqlite:///{tmp_path / 'metadata.db'}",
        repository_roots=(repositories,),
        local_source_roots=(sources,),
        restore_roots=(restores,),
        master_key_file=key,
        min_free_bytes=1,
    )


@pytest.mark.parametrize("name", ["existing", "outside", "root"])
def test_restore_destination_rejects_existing_or_outside_paths(tmp_path: Path, name: str) -> None:
    settings = settings_for(tmp_path)
    root = settings.restore_roots[0]
    outside = tmp_path / "outside"
    outside.mkdir()
    existing = root / "existing"
    existing.mkdir()
    destinations = {
        "existing": existing,
        "outside": outside / "restore",
        "root": root,
    }

    with pytest.raises(snapshot.SnapshotError):
        snapshot.validate_restore_destination(settings, str(destinations[name]))


def test_restore_strips_special_permission_bits(tmp_path: Path) -> None:
    target = tmp_path / "restored"
    target.write_bytes(b"content")

    snapshot._apply_metadata(
        target,
        {"metadata_support": ["mode"], "mode": 0o7777},
    )

    mode = stat.S_IMODE(target.stat().st_mode)
    assert mode == 0o777
    assert mode & (stat.S_ISUID | stat.S_ISGID | stat.S_ISVTX) == 0


def test_restore_destination_rejects_a_symlinked_parent(tmp_path: Path) -> None:
    settings = settings_for(tmp_path)
    outside = tmp_path / "outside"
    outside.mkdir()
    (settings.restore_roots[0] / "linked").symlink_to(outside, target_is_directory=True)

    with pytest.raises(snapshot.SnapshotError):
        snapshot.validate_restore_destination(
            settings, str(settings.restore_roots[0] / "linked" / "restore")
        )