/**
 * 设备指纹生成 - 跨平台
 * 基于: 主机名 + 用户名 + CPU ID + 磁盘序列号 + 架构
 * 输出 SHA-256 hex (64 字符)
 */
const crypto = require("crypto");
const os = require("os");
const { execSync } = require("child_process");

function safeExec(cmd) {
  try {
    return execSync(cmd, { encoding: "utf8", timeout: 3000, windowsHide: true }).toString();
  } catch { return ""; }
}

function cpuId() {
  if (process.platform === "win32") {
    // 用绝对路径防 PATH 污染
    const wmic = "C:\\Windows\\System32\\wbem\\wmic.exe";
    const out = safeExec(`"${wmic}" cpu get ProcessorId /value`);
    const m = out.match(/ProcessorId=([A-F0-9]+)/i);
    return m ? m[1] : "";
  }
  if (process.platform === "darwin") {
    const out = safeExec("system_profiler SPHardwareDataType");
    const m = out.match(/Hardware UUID:\s+([A-F0-9-]+)/);
    return m ? m[1] : "";
  }
  // Linux
  return safeExec("cat /etc/machine-id 2>/dev/null").trim();
}

function diskSerial() {
  if (process.platform === "win32") {
    const wmic = "C:\\Windows\\System32\\wbem\\wmic.exe";
    const out = safeExec(`"${wmic}" diskdrive get SerialNumber /value`);
    const lines = out.split(/\r?\n/).filter(l => /SerialNumber=.+/.test(l));
    return lines[0]?.split("=")[1]?.trim() || "";
  }
  if (process.platform === "darwin") {
    const out = safeExec("diskutil info /");
    const m = out.match(/Volume UUID:\s+([A-F0-9-]+)/);
    return m ? m[1] : "";
  }
  return safeExec("lsblk -no SERIAL 2>/dev/null | head -1").trim();
}

function fingerprint() {
  const raw = [
    os.hostname(),
    os.userInfo().username,
    cpuId(),
    diskSerial(),
    os.arch()
  ].join("::");
  return crypto.createHash("sha256").update(raw).digest("hex");
}

module.exports = { fingerprint };

if (require.main === module) {
  // 直接运行时打印指纹
  console.log(fingerprint());
}