# -*- coding: utf-8 -*-
"""验证 MTU 调优脚本和安装集成。

为什么值得单独回归：
    这是这次可用率从 48% 提到 100% 的关键，而且**很容易被后人误改** ——
    比如"顺手把接口 MTU 也降一点"（实测那样会掉到 50%）。
    所以把关键决策钉在测试里。
"""
from __future__ import annotations

import re
import subprocess
import sys
from pathlib import Path

ROOT = Path(__file__).resolve().parent.parent
NET_TUNE = ROOT / "relay" / "net-tune.sh"
INSTALL = ROOT / "relay" / "install.sh"

passed = 0
failed = 0


def check(name, ok, detail=""):
    global passed, failed
    if ok:
        passed += 1
        print("  [PASS] " + name)
    else:
        failed += 1
        print("  [FAIL] " + name + "  " + str(detail))


def main() -> int:
    print("一、调优脚本本身")
    check("net-tune.sh 在", NET_TUNE.is_file())
    if not NET_TUNE.is_file():
        return 1
    text = NET_TUNE.read_text(encoding="utf-8")

    # bash 语法（在 Linux 上才有 bash，本机没有就跳过）
    check("打开 tcp_mtu_probing", "tcp_mtu_probing=1" in text)
    check("夹 MSS", "--set-mss" in text)
    check("MSS 默认值合理（1300~1440）",
          bool(re.search(r"MSS_VALUE=\$\{MSS_VALUE:-(\d+)\}", text))
          and 1300 <= int(re.search(r"MSS_VALUE=\$\{MSS_VALUE:-(\d+)\}", text)
                          .group(1)) <= 1440,
          re.search(r"MSS_VALUE=.*", text).group(0) if "MSS_VALUE" in text else "")
    check("OUTPUT 链上夹", "OUTPUT" in text)
    check("POSTROUTING 链上夹", "POSTROUTING" in text)

    # 关键：明确写了不要改接口 MTU，并且确实把接口 MTU 设回 1500
    check("不把接口 MTU 调小（写回了 1500）",
          "mtu 1500" in text, "接口 MTU 降到 1400 实测会掉到 50%")
    check("注释里说明了为什么不动接口 MTU",
          "不要改接口 MTU" in text or "反而" in text)

    # 清理旧规则，避免重启后越积越多
    check("会先清掉旧 MSS 规则", "-D" in text and "while" in text)

    print()
    print("二、安装脚本带上了它")
    check("install.sh 在", INSTALL.is_file())
    install = INSTALL.read_text(encoding="utf-8")
    check("有 [3c] 网络调优段", "[3c]" in install)
    check("会拷 net-tune.sh", "net-tune.sh" in install)
    check("会写 sysctl 配置", "99-lanremote-mtu.conf" in install)
    check("会注册开机服务", "lanremote-nettune.service" in install)
    check("服务 enabled", "systemctl enable lanremote-nettune" in install)
    check("开机服务在隧道之前跑（新连接就用上新参数）",
          "Before=lanremote-relay.service lanremote-tunnel.service" in install)

    print()
    print("三、打包会带上这两个文件")
    package = (ROOT / "_build" / "package_remote.py").read_text(
        encoding="utf-8")
    check("打包脚本扫描整个 relay 目录（不是硬编码文件名）",
          "iterdir" in package or "rglob" in package, "")
    check("relay/net-tune.sh 会被打进去（同目录扫描即可）",
          NET_TUNE.is_file())

    print()
    print("四、说明文档里记了实测数据")
    check("写了不夹 MSS 的对照（87%）", "87" in text)
    check("写了 MSS 各档都 100%", "100%" in text)
    check("写了接口 MTU 1400 更差的教训", "50%" in text)

    print()
    print("=" * 58)
    print(f"通过 {passed} 项，失败 {failed} 项")
    return 0 if failed == 0 else 1


if __name__ == "__main__":
    sys.exit(main())