"""run_job 研究子进程入口的平台/配置分支单测。

覆盖点（Review 补测）：
- `_apply_memory_limit` 成功路径确实施加了请求的上限；
- 环境变量缺失时回退 `Settings.job_memory_limit_gb`；
- setrlimit 失败（如 macOS 上限额低于进程虚拟地址空间基线 → EINVAL/ValueError）
  **不得抛出**，否则研究子进程启动即失败；
- `_subprocess_log_target` 落盘失败时退回 DEVNULL —— 记日志失败不能拖垮 Job。
"""

from __future__ import annotations

import resource

import pytest
from app.application.services import job_executor as je
from app.cli import run_job


def test_apply_memory_limit_sets_requested_value(monkeypatch) -> None:
    captured: dict = {}
    monkeypatch.setenv("QLIB_JOB_MEM_LIMIT_GB", "3")
    monkeypatch.setattr(resource, "setrlimit", lambda which, lim: captured.update(w=which, lim=lim))

    run_job._apply_memory_limit()

    assert captured["w"] == resource.RLIMIT_AS
    assert captured["lim"] == (3 * 1024**3, 3 * 1024**3)


def test_apply_memory_limit_falls_back_to_settings(monkeypatch) -> None:
    """未设 QLIB_JOB_MEM_LIMIT_GB 时用 Settings 的上限（config.yaml job.max_memory_gb）。"""
    from app.core.config import get_settings

    captured: dict = {}
    monkeypatch.delenv("QLIB_JOB_MEM_LIMIT_GB", raising=False)
    monkeypatch.setattr(resource, "setrlimit", lambda which, lim: captured.update(lim=lim))

    run_job._apply_memory_limit()

    gb = get_settings().job_memory_limit_gb
    assert captured["lim"] == (gb * 1024**3, gb * 1024**3)


def test_apply_memory_limit_failure_does_not_raise(monkeypatch, capsys) -> None:
    """setrlimit 失败（macOS 限额低于地址空间基线的典型情形）只提示、不抛出。"""

    def _boom(which, lim):  # noqa: ANN001
        raise ValueError("current limit exceeds maximum limit")

    monkeypatch.setenv("QLIB_JOB_MEM_LIMIT_GB", "6")
    monkeypatch.setattr(resource, "setrlimit", _boom)

    run_job._apply_memory_limit()  # 不应抛异常

    err = capsys.readouterr().err
    assert "内存上限 6GB 设置失败" in err
    assert "无内存隔离保护" in err


def test_subprocess_log_target_falls_back_to_devnull(tmp_path, monkeypatch) -> None:
    """日志目录不可创建时退回 DEVNULL，不影响 Job 执行。"""
    blocker = tmp_path / "not-a-dir"
    blocker.write_text("x", encoding="utf-8")
    monkeypatch.setattr(je, "BACKEND_ROOT", blocker / "sub")

    assert je._subprocess_log_target() is je.subprocess.DEVNULL


def test_subprocess_log_target_writes_under_project_logs(tmp_path, monkeypatch) -> None:
    """正常路径：在 <项目根>/logs/job-subprocess.log 追加写入。"""
    monkeypatch.setattr(je, "BACKEND_ROOT", tmp_path / "backend")

    target = je._subprocess_log_target()
    try:
        target.write("hello-subprocess\n")
    finally:
        target.close()

    assert (tmp_path / "logs" / "job-subprocess.log").read_text(encoding="utf-8") == (
        "hello-subprocess\n"
    )


if __name__ == "__main__":  # pragma: no cover
    raise SystemExit(pytest.main([__file__, "-q"]))