#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import json
import re
import subprocess
import urllib.parse
import platform
import shutil
from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer

HOST = "127.0.0.1"
PORT = 39393
PING_TIMEOUT_MS = 1000
PING_COUNT = 1


def json_bytes(data):
    return json.dumps(data, ensure_ascii=False).encode("utf-8")


def parse_ping_output(output: str):
    lower_output = output.lower()
    success = False
    if "ttl=" in lower_output:
        success = True
    if "reply from" in lower_output:
        success = True
    if "来自" in output and "ttl=" in lower_output:
        success = True

    times = []
    matches = re.findall(r"(?:time|时间)\s*[=<]?\s*(\d+)\s*ms", output, re.IGNORECASE)
    for m in matches:
        try:
            times.append(int(m))
        except Exception:
            pass

    response_time = round(sum(times) / len(times)) if times else None

    if success:
        status_text = "在线"
    else:
        if "请求超时" in output or "request timed out" in lower_output:
            status_text = "请求超时"
        elif "无法访问目标主机" in output or "destination host unreachable" in lower_output:
            status_text = "目标不可达"
        elif "一般故障" in output or "general failure" in lower_output:
            status_text = "网络故障"
        else:
            status_text = "离线"

    return success, response_time, status_text


def run_ping(ip: str):
    cmd = ["ping", ip, "-n", str(PING_COUNT), "-w", str(PING_TIMEOUT_MS)]
    try:
        result = subprocess.run(
            cmd,
            capture_output=True,
            text=True,
            encoding="gbk",
            errors="ignore",
            timeout=8
        )
    except subprocess.TimeoutExpired:
        return {"ok": True, "online": False, "ip": ip, "responseTime": None, "statusText": "检测超时", "raw": "ping timeout"}
    except Exception as e:
        return {"ok": False, "online": False, "ip": ip, "responseTime": None, "statusText": "本地检测异常", "error": str(e)}

    output = ((result.stdout or "") + "\n" + (result.stderr or "")).strip()
    success, response_time, status_text = parse_ping_output(output)
    return {"ok": True, "online": success, "ip": ip, "responseTime": response_time, "statusText": status_text, "raw": output}


class Handler(BaseHTTPRequestHandler):
    def _cors(self):
        self.send_header("Access-Control-Allow-Origin", "*")
        self.send_header("Access-Control-Allow-Methods", "GET, OPTIONS")
        self.send_header("Access-Control-Allow-Headers", "Content-Type")

    def do_OPTIONS(self):
        self.send_response(204)
        self._cors()
        self.end_headers()

    def do_GET(self):
        parsed = urllib.parse.urlparse(self.path)

        if parsed.path == "/health":
            body = json_bytes({
                "ok": True,
                "service": "local-ping-proxy",
                "pythonVersion": platform.python_version(),
                "pingCount": PING_COUNT,
                "timeoutMs": PING_TIMEOUT_MS,
                "pingCommand": shutil.which('ping') is not None,
            })
            self.send_response(200)
            self._cors()
            self.send_header("Content-Type", "application/json; charset=utf-8")
            self.send_header("Content-Length", str(len(body)))
            self.end_headers()
            self.wfile.write(body)
            return

        if parsed.path == "/ping":
            qs = urllib.parse.parse_qs(parsed.query)
            ip = (qs.get("ip", [""])[0] or "").strip()
            if not ip:
                body = json_bytes({"ok": False, "online": False, "statusText": "缺少 IP 参数", "error": "missing ip"})
                self.send_response(400)
                self._cors()
                self.send_header("Content-Type", "application/json; charset=utf-8")
                self.send_header("Content-Length", str(len(body)))
                self.end_headers()
                self.wfile.write(body)
                return

            data = run_ping(ip)
            body = json_bytes(data)
            self.send_response(200)
            self._cors()
            self.send_header("Content-Type", "application/json; charset=utf-8")
            self.send_header("Content-Length", str(len(body)))
            self.end_headers()
            self.wfile.write(body)
            return

        body = json_bytes({"ok": False, "error": "not found"})
        self.send_response(404)
        self._cors()
        self.send_header("Content-Type", "application/json; charset=utf-8")
        self.send_header("Content-Length", str(len(body)))
        self.end_headers()
        self.wfile.write(body)

    def log_message(self, format, *args):
        pass


if __name__ == "__main__":
    server = ThreadingHTTPServer((HOST, PORT), Handler)
    print("=" * 60)
    print("本地检测助手已启动")
    print(f"地址: http://{HOST}:{PORT}")
    print("作用: 接收网页请求，在当前电脑本机执行 ping，并把结果返回给网页")
    print("说明: 只有这个窗口保持开启，网页里的“开始测试”才会生效")
    print("提醒: 测试期间请不要关闭这个窗口")
    print("=" * 60)
    server.serve_forever()