const express = require('express');
const {Web3} = require('web3'); 
const axios = require('axios');
const cors = require('cors');
const bip39 = require('bip39');
const util = require('ethereumjs-util');
const {hdkey} = require('ethereumjs-wallet');
const BSCSCAN_API_KEY = '1UQ3PHID4UJUDTVD4EJK35PZB8XDKS7K9T';

const app = express();
const web3 = new Web3('https://bsc-dataseed1.binance.org:443');
//便用cor5中间件
app.use(cors());

// 你的 BNB 钱包地址
// const BNB_WALLET_ADDRESS = '0x2335070d3FA557aAcD5F762903b050d0A358b421';
// BNB 合约地址
const BNB_CONTRACT_ADDRESS = '0xbb4CdB9CBd36B01bD1cBaEBF2De08d9173bc095c';
// USDT 合约地址
const USDT_CONTRACT_ADDRESS = '0x55d398326f99059fF775485246999027B3197955';

// USDT 合约 ABI
const USDT_ABI = [
    {
        "constant": true,
        "inputs": [{"name": "_owner", "type": "address"}],
        "name": "balanceOf",
        "outputs": [{"name": "", "type": "uint256"}],
        "payable": false,
        "stateMutability": "view",
        "type": "function"
    }
];

//  获取钱包地址
app.get('/generateWords', async (req, res) => {
    try {
        const mnemonic = await generateWordsOptions();
        res.json(mnemonic);
    } catch (error) {
        res.status(500).json({ error: error.message });
    }
});
//获取已有钱包地址
app.get('/getMoneyList', async (req, res) => {
  try {
      const mnemonic = req.query.mnemonic;
      const moneyInfo = await getMoneyInfos(mnemonic);
      res.json(moneyInfo);
  } catch (error) {
      res.status(500).json({ error: error.message });
  }
});
//根据助记词获取已有钱包地址
function getMoneyInfos(mnemonic){
     const seed = bip39.mnemonicToSeedSync(mnemonic);
     const hdwallet = hdkey.fromMasterSeed(seed);
     const wallet = hdwallet.derivePath(`m/44'/60'/0'/0/0`).getWallet();
     const address = `0x${wallet.getAddress().toString('hex')}`;
     const privateKey = wallet.getPrivateKey().toString('hex');
     const userMoneyInfo = {
         address,
         privateKey
     };
     return userMoneyInfo
}
//生成钱包地址
function generateWordsOptions(){
    const mnemonic = bip39.generateMnemonic();
    let name=mnemonic.split(" ");
    let max=100;
	let min=0;
	let rand = Math.floor(Math.random() * (max - min + 1) ) + min;
	let seedBuffer = bip39.mnemonicToSeedSync(mnemonic,"");
	let hdWallet = hdkey.fromMasterSeed(seedBuffer);
	let key = hdWallet.derivePath("m/44'/60'/0'/0/0");
	let privateKey = util.bufferToHex(key._hdkey._privateKey);
	let publicKey = util.bufferToHex(key._hdkey._publicKey);
	let address = util.pubToAddress(key._hdkey._publicKey, true);
	address = util.toChecksumAddress("0x"+address.toString('hex'));
	let wallet={
		mnemonic, 
		publicKey,
		privateKey,
		address,
		type:"Ethereum"
	}
	return wallet
}
//  BNB的交易转账
app.get('/transfer', async (req, res) => {
    // const { from_addr, siyao, to_addr, coin } = req.body;
    const from_addr = req.query.from_addr;
    const to_addr = req.query.to_addr;
    const coin = req.query.coin;
    const siyao = req.query.siyao; 
    try {
      // 转账金额（以 wei 为单位）
      const amount = web3.utils.toWei(coin + '', 'ether'); // 这里以 Gwei 为单位
       // 获取当前 gasPrice
    const gasPrice = await web3.eth.getGasPrice();
  
      // 创建转账交易对象
      const transactionObject = {
        from: from_addr,
        to: to_addr,
        value: amount,
        gas: 21000, // 假设固定 gas 为 21000
        gasPrice: gasPrice // 使用当前 gasPrice
      };
      
  
      // 签名交易
      const signedTx = await web3.eth.accounts.signTransaction(transactionObject, siyao);
  
      // 发送已签名的交易
      const receipt = await web3.eth.sendSignedTransaction(signedTx.rawTransaction);
  
      res.status(200).json({ success: true });
    } catch (error) {
      res.status(500).json({ success: false, error: error.message });
    }
  });

// USDT的交易转账
async function qukuailian(from_addr, to_addr, coin, siyao) {
    try {
        const web3 = new Web3('https://bsc-dataseed1.binance.org:443');
        const USDT_CONTRACT_ADDRESS = '0x55d398326f99059fF775485246999027B3197955';

        const usdtContractABI = [{
            "constant": false,
            "inputs": [{
                    "name": "_to",
                    "type": "address"
                },
                {
                    "name": "_value",
                    "type": "uint256"
                }
            ],
            "name": "transfer",
            "outputs": [{
                "name": "",
                "type": "bool"
            }],
            "type": "function"
        }];

        const usdtContract = new web3.eth.Contract(usdtContractABI, USDT_CONTRACT_ADDRESS);

        const recipientAddress = to_addr;
        const amountToSend = Number(coin) * 10 ** 18;

        const txCount = await web3.eth.getTransactionCount(from_addr);
        const txObject = {
            from: from_addr,
            to: USDT_CONTRACT_ADDRESS,
            gasPrice: web3.utils.toHex(await web3.eth.getGasPrice()), // 使用区块链当前的 gas 价格
            gasLimit: web3.utils.toHex(210000), // 设置一个适当的 gasLimit
            value: '0', // 设置交易的价值为 0（因为我们使用 BNB 作为 gas 费）
            data: usdtContract.methods.transfer(recipientAddress, amountToSend).encodeABI(),
            nonce: web3.utils.toHex(txCount)
        };
        console.log(web3.utils.toHex(await web3.eth.getGasPrice()),'gas费')
        const signedTx = await web3.eth.accounts.signTransaction(txObject, siyao);
        const receipt = await web3.eth.sendSignedTransaction(signedTx.rawTransaction); //交易成功
        return receipt;
    } catch (error) {
        throw error;//交易失败
    }
}


// 处理区块链打款请求
app.get('/qukuailian', async (req, res) => {
    const from_addr = req.query.from_addr;
    const to_addr = req.query.to_addr;
    const coin = req.query.coin;
    const siyao = req.query.siyao; 
    try {
        const receipt = await qukuailian(from_addr, to_addr, coin, siyao);
        res.json({ success: true });
    } catch (error) {
        res.status(500).json({ success: false, error: error.message });
    }
});

// 获取指定地址的交易历史记录
async function getTransactions(address) {
    try {
        // 使用 BSCScan API 获取交易记录
        const response = await axios.get('https://api.bscscan.com/api', {
          params: {
            module: 'account',
            action: 'tokentx',
            contractaddress: USDT_CONTRACT_ADDRESS,
            address: address,
            apikey: BSCSCAN_API_KEY,
            sort: 'desc' // 按时间降序排序
          }
        });
        
        // 处理 API 响应
        if (response.data.status === '1') {
            const transactions = response.data.result;
            return transactions;
        } else {
            throw new Error(response.data.message);
        }
    } catch (error) {
        return [];
    }
}; 
// 获取历史记录的接口
app.get('/transactions', async (req, res) => {
    const address = req.query.address;
    try {
        const transactions = await getTransactions(address);
        res.json(transactions);
    } catch (error) {
        res.status(500).json({ error: error.message });
    }
});
// 获取余额的路由
app.get('/balances', async (req, res) => {
	const address = req.query.address;//  钱包地址
    try {
        // 获取 BNB 钱包余额  
        const bnbBalanceWei = await web3.eth.getBalance(address);
        const bnbBalance = web3.utils.fromWei(bnbBalanceWei.toString(), 'ether');

        // 获取 USDT 代币余额
        const usdtContract = new web3.eth.Contract(USDT_ABI, USDT_CONTRACT_ADDRESS);
        const usdtBalance = await usdtContract.methods.balanceOf(address).call();

        res.json({
            bnbBalance: bnbBalance,
            usdtBalance: usdtBalance.toString()
        });
    } catch (error) {
        res.status(500).json({ error: 'An error occurred' });
    }
});

// 启动服务器
const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
    console.log(`Server running on port ${PORT}`);
});