#!/usr/bin/env python3
"""把 direct.yaml（真源）生成为 Clash Verge 的全局增强脚本 Script.js。

用法：
  python3 scripts/gen_clash_verge_script.py [--out 目标路径]

默认按 Windows/macOS 平台输出到 Clash Verge 数据目录 profiles/Script.js（全局直连
规则的唯一正确机制）。生成后需在 Clash Verge 界面点「重启内核」生效。
"""
import argparse
import os
from pathlib import Path
import sys

REPO_ROOT = Path(__file__).resolve().parent.parent
APP_ID = "io.github.clash-verge-rev.clash-verge-rev"


def default_output_path(
    platform_name: str = sys.platform,
    *,
    home: Path | None = None,
    appdata: Path | None = None,
) -> Path:
    """返回当前平台的 Clash Verge 全局 Script.js 路径。"""
    home = home or Path.home()
    if platform_name == "win32":
        if appdata is None:
            roaming = os.environ.get("APPDATA")
            if not roaming:
                raise SystemExit("[error] Windows 环境缺少 APPDATA，无法定位 Clash Verge 数据目录")
            appdata = Path(roaming)
        return appdata / APP_ID / "profiles" / "Script.js"
    if platform_name == "darwin":
        return home / "Library/Application Support" / APP_ID / "profiles" / "Script.js"
    return home / ".local/share" / APP_ID / "profiles" / "Script.js"


DEFAULT_OUT = default_output_path()


def load_payload(path: Path) -> list[str]:
    payload: list[str] = []
    with path.open(encoding="utf-8") as f:
        for line in f:
            line = line.strip()
            if line.startswith("- "):
                payload.append(line[2:].strip())
    if not payload:
        raise SystemExit(f"[error] direct.yaml 里没有 payload 条目: {path}")
    return payload


def to_rule(entry: str) -> str:
    """rule-provider 条目（无策略）→ 完整规则（补 DIRECT）。"""
    if entry.endswith(",no-resolve"):
        return f"{entry[:-len(',no-resolve')]},DIRECT,no-resolve"
    return f"{entry},DIRECT"


def render_script(payload: list[str]) -> str:
    rules = [f"  {to_rule(e)!r}," for e in payload]
    lines = "\n".join(rules)
    return f"""// 由 vpn-rules/direct.yaml 生成 — 勿手改，改真源后重跑 gen_clash_verge_script.py。
// 全局直连规则：OneDrive、FRP 控制面、B站、国内 LLM、内网段、国区 iCloud、UGREEN 一律 DIRECT。
const prependRules = [
{lines}
];

// 国内可达的 DoH 同时作为 fallback，确保 OneDrive 等境外域名在 DIRECT 出站前可解析。
const directDnsFallbacks = [
  'https://dns.alidns.com/dns-query',
  'https://doh.pub/dns-query',
];

function main(config, profileName) {{
  const existingRules = Array.isArray(config.rules) ? config.rules : [];
  const existingRuleSet = new Set(existingRules);
  const dns = config.dns && typeof config.dns === 'object' && !Array.isArray(config.dns)
    ? config.dns
    : {{}};
  const existingFallbacks = Array.isArray(dns.fallback)
    ? dns.fallback
    : (typeof dns.fallback === 'string' ? [dns.fallback] : []);
  const existingFallbackSet = new Set(existingFallbacks);

  config.rules = [
    ...prependRules.filter((rule) => !existingRuleSet.has(rule)),
    ...existingRules,
  ];
  dns.fallback = [
    ...directDnsFallbacks.filter((server) => !existingFallbackSet.has(server)),
    ...existingFallbacks,
  ];
  config.dns = dns;

  return config;
}}
"""


def main() -> None:
    ap = argparse.ArgumentParser(description="direct.yaml → Clash Verge Script.js")
    ap.add_argument("--out", default=str(DEFAULT_OUT), help="输出路径")
    args = ap.parse_args()

    payload = load_payload(REPO_ROOT / "direct.yaml")
    script = render_script(payload)
    out = Path(args.out)
    out.parent.mkdir(parents=True, exist_ok=True)
    out.write_text(script, encoding="utf-8")
    print(f"[ok] 已生成 {out}（{len(payload)} 条规则）")
    print("   请在 Clash Verge 界面点「重启内核」生效。")


if __name__ == "__main__":
    main()