buy_token_pancakeswap.js

const Web3 = require('web3');
const fs = require('fs');

const gasPriceTokenApproval = '5.5'; // Set your desired gas price in Gwei for token approval
const gasPricePancakeSwap = '10';

// Connect to the BSC network using a provider URL
const providerUrl = 'https://bsc-dataseed.binance.org';
const web3 = new Web3(providerUrl);

// Important variables
const tokenContractAddress = '0xaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa';
const walletPrivateKey = 'bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb';

const walletAddress = '0xcccccccccccccccccccccccccccccccccccccccc';

// Set up the PancakeSwap contract
const pancakeswapContractAddress = '0x05fF2B0DB69458A0750badebc4f9e13aDd608C7F';
const pancakeswapAbi = JSON.parse(fs.readFileSync('pancakeswap_abi.json', 'utf8'));
const pancakeswapContract = new web3.eth.Contract(pancakeswapAbi, pancakeswapContractAddress);

// Set up the token contract
const tokenAbi = JSON.parse(fs.readFileSync('token_abi.json', 'utf8'));
const tokenContract = new web3.eth.Contract(tokenAbi, tokenContractAddress);

// Set up the token information
const tokenDecimalFactor = 10 ** 18; // 18 decimal places
const tokenAmount = '1000000000000000000'; // Replace with your desired value

// Approve PancakeSwap to spend your tokens
const tokenApproveMethod = tokenContract.methods.approve(
  pancakeswapContractAddress,
  tokenAmount //* tokenDecimalFactor
);
let nonce = web3.eth.getTransactionCount(walletAddress);

const tokenApproveTx = {
  gas: 500000,
  gasPrice: web3.utils.toWei(gasPriceTokenApproval, 'gwei'), // Set gas price directly
  from: walletAddress,
  nonce: nonce,
  data: tokenApproveMethod.encodeABI(),
  to: tokenContractAddress
};
nonce += 1;

web3.eth.accounts.signTransaction(tokenApproveTx, walletPrivateKey)
  .then((signedApproveTx) => {
    web3.eth.sendSignedTransaction(signedApproveTx.rawTransaction)
      .on('transactionHash', (txHash) => {
        console.log('Token approval transaction hash:', txHash);
      })
      .on('receipt', (receipt) => {
        // Check if the transaction was successful or reverted
        if (receipt.status) {
          // Purchase tokens on PancakeSwap
          const latestBlock = web3.eth.getBlock('latest');
          const pancakeSwapMethod = pancakeswapContract.methods.swapExactETHForTokens(
            0,
            [web3.utils.toChecksumAddress('0xbb4CdB9CBd36B01bD1cBaEBF2De08d9173bc095c'), tokenContractAddress],
            walletAddress,
            web3.eth.getBlock('latest').timestamp + 10 // The transaction will be valid for 10 more seconds
          );
          const pancakeSwapTx = {
            gas: 500000,
            gasPrice: web3.utils.toWei(gasPricePancakeSwap, 'gwei'), // Set gas price directly
            from: walletAddress,
            nonce: nonce,
            value: web3.utils.toWei('0.005', 'ether'),
            data: pancakeSwapMethod.encodeABI(),
            to: pancakeswapContractAddress
          };

          web3.eth.accounts.signTransaction(pancakeSwapTx, walletPrivateKey)
            .then((signedSwapTx) => {
              web3.eth.sendSignedTransaction(signedSwapTx.rawTransaction)
                .on('transactionHash', (txHash) => {
                  console.log('PancakeSwap transaction hash:', txHash);
                })
                .on('receipt', (receipt) => {
                  // Check if the transaction was successful or reverted
                  if (receipt.status) {
                    console.log('PancakeSwap transaction successful');
                  } else {
                    // Transaction reverted, extract and decode the revert reason
                    const revertReason = web3.utils.hexToAscii(receipt.receipt.rawLogs[0].data);
                    console.log('PancakeSwap transaction reverted:', revertReason);
                  }
                })
                .catch((error) => {
                  console.log('Failed to send PancakeSwap transaction:', error);
                });
            })
            .catch((error) => {
              console.log('Failed to sign PancakeSwap transaction:', error);
            });
        } else {
          // Transaction reverted, extract and decode the revert reason
          const revertReason = web3.utils.hexToAscii(receipt.receipt.rawLogs[0].data);
          console.log('Token approval transaction reverted:', revertReason);
        }
      })
      .catch((error) => {
        console.log('Failed to send token approval transaction:', error);
      });
  })
  .catch((error) => {
    console.log('Failed to sign token approval transaction:', error);
  });