"""数据库提交失败时，上传文件恢复到原状且保留原始异常。"""

from contextlib import nullcontext
from types import SimpleNamespace
from unittest.mock import Mock

import pytest

from app.services import system_setting_service as service


@pytest.mark.parametrize("old_ext", [None, "png", "jpg"])
def test_提交失败不丢旧logo也不残留新文件(tmp_path, monkeypatch, old_ext):
    original = b"original-logo"
    if old_ext:
        (tmp_path / f"logo.{old_ext}").write_bytes(original)
    monkeypatch.setattr(service, "_logo_dir", lambda: tmp_path)
    setting = SimpleNamespace(logo_path=f"logo/logo.{old_ext}" if old_ext else None)
    monkeypatch.setattr(service, "get_setting", lambda _: setting)
    monkeypatch.setattr(service.audit_service, "audit", lambda *_, **__: nullcontext())
    session = Mock()
    session.commit.side_effect = RuntimeError("数据库提交失败")
    with pytest.raises(RuntimeError, match="数据库提交失败"):
        service.save_logo(session, service._MAGIC["png"] + b"new", "png", operator=Mock())
    if old_ext == "png":
        assert (tmp_path / "logo.png").read_bytes() == original
    else:
        assert not (tmp_path / "logo.png").exists()
    if old_ext:
        assert (tmp_path / f"logo.{old_ext}").read_bytes() == original