#!/usr/bin/env python3
"""Sanitized Clash-sub helpers. Never print or persist credentials."""

from __future__ import annotations

import collections
import json
import os
import re
import urllib.parse
from typing import Any

INFO_NAME_RE = re.compile(r"^(剩余流量|套餐到期|到期|流量)")

REGION_RULES: list[tuple[str, list[str]]] = [
    ("香港", ["香港", "HK", "🇭🇰"]),
    ("台湾", ["台湾", "臺灣", "🇹🇼"]),
    ("日本", ["日本", "东京", "大阪", "🇯🇵"]),
    ("韩国", ["韩国", "韓國", "首尔", "🇰🇷"]),
    ("新加坡", ["新加坡", "狮城", "🇸🇬"]),
    ("美国", ["美国", "美國", "圣何塞", "洛杉矶", "硅谷", "西雅图", "芝加哥", "纽约", "🇺🇸"]),
    ("英国", ["英国", "英國", "伦敦", "🇬🇧"]),
    ("德国", ["德国", "德國", "法兰克福", "🇩🇪"]),
    ("法国", ["法国", "法國", "巴黎", "🇫🇷"]),
    ("加拿大", ["加拿大", "🇨🇦"]),
    ("澳大利亚", ["澳大利亚", "澳洲", "🇦🇺"]),
    ("澳门", ["澳门", "澳門", "🇲🇴"]),
    ("中国", ["中国", "回国"]),
]


def infer_region(name: str) -> str:
    for label, keys in REGION_RULES:
        for key in keys:
            if key in name:
                return label
    return "其他/未知"


def is_info_node(name: str) -> bool:
    return bool(INFO_NAME_RE.search(name))


def parse_flow_proxies(text: str) -> list[dict[str, str]]:
    proxies: list[dict[str, str]] = []
    for line in text.splitlines():
        if "name:" not in line or "type:" not in line or "server:" not in line:
            continue
        name_m = re.search(r"name:\s*'([^']+)'|name:\s*([^,}]+)", line)
        type_m = re.search(r"type:\s*([a-zA-Z0-9-]+)", line)
        if not name_m or not type_m:
            continue
        name = (name_m.group(1) or name_m.group(2)).strip()
        proxies.append(
            {
                "name": name,
                "type": type_m.group(1),
                "region": infer_region(name),
            }
        )
    return proxies


def detect_format(text: str) -> str:
    head = text.lstrip()[:400]
    if "proxies:" in text[:4000] and (
        "mixed-port:" in head or "port:" in head or head.startswith("proxies:")
    ):
        return "clash-yaml"
    if any(head.startswith(s) for s in ("ss://", "vmess://", "trojan://", "vless://")):
        return "uri-list"
    compact = re.sub(r"\s+", "", text)
    if compact and re.fullmatch(r"[A-Za-z0-9+/=_-]+", compact[:80] or ""):
        return "base64-maybe"
    return "other"


def rewrite_runtime_config(src: str, mixed_port: int, controller: str) -> str:
    """Rewrite listen ports / controller; strip original rules to MATCH selector."""
    lines = src.splitlines()
    out: list[str] = []
    skipping_rules = False
    selector = "🚀节点选择"
    for line in lines:
        if line.startswith("proxy-groups:"):
            skipping_rules = False
        if line.startswith("rules:"):
            skipping_rules = True
            continue
        if skipping_rules:
            continue
        if line.startswith("mixed-port:"):
            out.append(f"mixed-port: {mixed_port}")
            continue
        if line.startswith("allow-lan:"):
            out.append("allow-lan: true")
            continue
        if line.startswith("external-controller:"):
            out.append(f"external-controller: '{controller}'")
            continue
        if line.startswith("bind-address:"):
            out.append("bind-address: '*'")
            continue
        out.append(line)
    out.append("rules:")
    out.append(f"    - MATCH,{selector}")
    return "\n".join(out) + "\n"


def mask_secret(value: str, keep: int = 4) -> str:
    if not value:
        return ""
    return value[:keep] + "***"


def summarize_subscription(text: str) -> dict[str, Any]:
    fmt = detect_format(text)
    proxies = parse_flow_proxies(text)
    real = [p for p in proxies if not is_info_node(p["name"])]
    info = [p for p in proxies if is_info_node(p["name"])]
    return {
        "format": fmt,
        "proxy_count_raw": len(proxies),
        "proxy_count_real": len(real),
        "info_nodes": [p["name"] for p in info],
        "types": dict(collections.Counter(p["type"] for p in real)),
        "regions": dict(collections.Counter(p["region"] for p in real)),
        "proxies": real,
    }


def api_quote(name: str) -> str:
    return urllib.parse.quote(name, safe="")


def require_sub_url() -> str:
    url = os.environ.get("PROXY_SUB_URL", "").strip()
    if not url:
        raise SystemExit("PROXY_SUB_URL is required (do not hardcode the URL)")
    if not url.startswith(("http://", "https://")):
        raise SystemExit("PROXY_SUB_URL must be an http(s) URL")
    return url


def dump_json(path: str, obj: Any) -> None:
    with open(path, "w", encoding="utf-8") as fh:
        json.dump(obj, fh, ensure_ascii=False, indent=2)
        fh.write("\n")