const LOCAL_KEY = "SUPABASE_URL";
const MAX_RETRIES = 5;
const RETRY_DELAY = 1000;

export async function getRuntimeEnv(key: string): Promise<string | undefined> {
  if (typeof window !== "undefined") {
    let retries = 0;
    while (retries < MAX_RETRIES) {
      // 1. 尝试 window.RUNTIME_ENV 提取IP
      const val = window.RUNTIME_ENV?.[key];
      const ip = extractIp(val);
      if (ip) {
        if (key === "SUPABASE_URL") {
          window.localStorage.setItem(LOCAL_KEY, val!); // 这里存原始值
          console.log(`[env] [${key}] 命中 window.RUNTIME_ENV: ${val}，提取IP: ${ip}，已同步到localStorage`);
        } else {
          console.log(`[env] [${key}] 命中 window.RUNTIME_ENV: ${val}，提取IP: ${ip}`);
        }
        return ip;
      } else if (val) {
        console.warn(`[env] [${key}] window.RUNTIME_ENV 有值但无法提取合法IP: ${val}`);
      }

      retries++;
      // 2. 第3次开始查localStorage兜底
      if (retries >= 2) {
        const cached = window.localStorage.getItem(LOCAL_KEY);
        const cachedIp = extractIp(cached);
        if (cachedIp && key === "SUPABASE_URL") {
          console.warn(`[env] [${key}] 第${retries}次重试后window.RUNTIME_ENV还没拿到合法IP，localStorage兜底: ${cached}，提取IP: ${cachedIp}`);
          return cachedIp;
        }
      }

      if (retries < MAX_RETRIES) {
        console.log(`[env] [${key}] window.RUNTIME_ENV 暂无合法IP，第${retries}次重试，${RETRY_DELAY}ms后再试...`);
        await new Promise(res => setTimeout(res, RETRY_DELAY));
      }
    }

    // 3. 所有重试和localStorage都失败
    console.error(`[env] [${key}] window.RUNTIME_ENV、localStorage都无合法IP，返回undefined`);
    return undefined;
  } else {
    // 服务端
    const val = process.env[key];
    const ip = extractIp(val);
    console.log(`[env][server] 直接读取 process.env[${key}]:`, val, "提取IP:", ip);
    return ip;
  }
}

// --------- 需要配合的工具函数 ---------
function isValidIp(ip: string | undefined): boolean {
  if (!ip) return false;
  const reg = /^(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)$/;
  return reg.test(ip);
}

function extractIp(str: string | undefined): string | undefined {
  if (!str) return undefined;
  if (isValidIp(str)) return str;
  try {
    const url = new URL(str);
    if (isValidIp(url.hostname)) return url.hostname;
  } catch {}
  const match = str.match(/(\d{1,3}(?:\.\d{1,3}){3})/);
  if (match && isValidIp(match[1])) return match[1];
  return undefined;
}