const fs = require("fs");
const path = require("path");
const { parse } = require("querystring");
const { createVerify, createPrivateKey } = require("crypto");
const NodeRSA = require('node-rsa');
const base64 = require('base-64');

const PRIVATE_KEY =`-----BEGIN RSA PRIVATE KEY-----
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
-----END RSA PRIVATE KEY-----`
const PUBLIC_KEY = "-----BEGIN PUBLIC KEY-----\n" + "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCv6trrrn/rOKXdoJFQMoR5KaINaOES+fg5tmTnuYuzvxCyib4//SSKzTtWmzTbhvINp7wZzniebootavN0MvQuGmnstVI6mHd4lbqbjvF35q/97B03nOkfF9B2Z7kP37FPLkRGBEBVHwRXGbYjc9k6l34yVzFwHk6V3Ogmyji3twIDAQAB" + "\n-----END PUBLIC KEY-----";


function longDecrypt(privateKey, msg) {
    // Format the private key
    privateKey = privateKey.match(/.{1,64}/g).join('\n');
    privateKey = `-----BEGIN RSA PRIVATE KEY-----\n${privateKey}\n-----END RSA PRIVATE KEY-----`;

    // Decode the base64 message
    const bufferMsg = Buffer.from(msg, 'base64');
    const length = bufferMsg.length;
    const defaultLength = 128;
    
    const key = new NodeRSA(privateKey, 'pkcs1');
    key.setOptions({ encryptionScheme: 'pkcs1' });

    let offset = 0;
    let res = [];

    while (length - offset > 0) {
        if (length - offset > defaultLength) {
            res.push(key.decrypt(bufferMsg.slice(offset, offset + defaultLength)));
        } else {
            res.push(key.decrypt(bufferMsg.slice(offset)));
        }
        offset += defaultLength;
    }

    return Buffer.concat(res).toString('utf8');
}


function verifyWebhook() {
  const parsedData = {"meta":{"success":true,"code":"0000","message":"Request Success"},"data":{"merchantNo":"AC202299319","merchantOrderNo":"DS202412311005240317","orderNo":"R08OC0241231100525384624557803","currency":"JPY","payType":"JAPAN_PAY","orderAmount":10000,"paidAmount":null,"orderFee":700,"payModel":"BankTransfer","orderStatus":"PENDING","webUrl":null,"page":null,"orderTime":1735610725000,"finishTime":0,"sign":"V0EZCULoPBG7q8CuWxSnAkTnigjPbX49IquVzqH8TZ2Kp+SYJmXAmAWPLKPWWTQdvAw99T3PrkEMmutKfCE2zEay5uKhtHU8BY4T0phLr8cU3G9MTWNjp3AJ/dtJ6nh19/L20vis5anvj0aC4ShnEcIzfVeWtWszT+meu7LC4Js52C9vmGGKtPWUUbD6zV/+3YYnNxf/BIEBLOewWIaHccne6E37wbzjbHWczAPecka/E7KOGPyG2PPa67Y5ixsGUjhSD6RHHjbXKJatD8+vTa4BpwieQ4FZTF1dF2oCWJjVOLiB4ZSwMs4vRf9bb0GhWmJuf1N45eWWJkMRJ+392A==","remark":"","errorMessage":null,"descriptor":null},"sign":"589092dbe5aca882cfcc409d1f868d0e"};

  const dataJson = parsedData.data;
  console.log("Decoded data:", JSON.stringify(dataJson, null, 2));

  // 提取签名
  const sign = dataJson.sign;
  delete dataJson.sign;
  console.log("Signature:", sign);

  // 生成待签名的字符串
  function createSortedDataString(data) {
    const validKeys = [
      "merchantNo",
      "merchantOrderNo",
      "orderNo",
      "currency",
      "orderAmount",
      "orderFee",
      "payModel",
      "orderStatus",
      "payType",
    ];
    const sortedData = Object.keys(data)
      .filter((key) => validKeys.includes(key))
      .sort()
      .map((key) => `${key}=${data[key]}`)
      .join("&");
    return sortedData;
  }

  const signStr = createSortedDataString(dataJson);
  console.log("String to be signed:", signStr);

  // 验证签名
  try {
    const verify = createVerify("SHA256");
    verify.update(signStr);
    verify.end();

    // const isVerified = verify.verify(PRIVATE_KEY, sign, "base64");
    const isVerified = longDecrypt(PRIVATE_KEY, sign);
    console.log(58, isVerified);

    if (isVerified) {
      console.log("Verification passed");
      return true;
    } else {
      console.log("Verification failed");
      return false;
    }
  } catch (error) {
    console.error(`Decryption error: ${error.message}`);
    return false;
  }
}

verifyWebhook();