eth_getTransactionCount - Mantle RPC Method

import { JsonRpcProvider, Wallet, parseEther } from 'ethers';

const provider = new JsonRpcProvider('https://api-mantle-mainnet.n.dwellir.com/YOUR_API_KEY');

class TransactionSender {
  constructor(privateKey) {
    this.wallet = new Wallet(privateKey, provider);
    this.localNonce = null;
  }

  async getNextNonce() {
    // Get the pending nonce from the network
    const pendingNonce = await provider.getTransactionCount(
      this.wallet.address, 'pending'
    );

    // Use whichever is higher: local tracker or network pending
    if (this.localNonce === null || pendingNonce > this.localNonce) {
      this.localNonce = pendingNonce;
    }

    const nonce = this.localNonce;
    this.localNonce++;
    return nonce;
  }

  async sendTransaction(to, valueEth) {
    const nonce = await this.getNextNonce();

    const tx = await this.wallet.sendTransaction({
      to,
      value: parseEther(valueEth),
      nonce
    });

    console.log(`Sent tx ${tx.hash} with nonce ${nonce}`);
    return tx;
  }

  // Reset local nonce tracker (e.g., after errors)
  resetNonce() {
    this.localNonce = null;
  }
}

async function detectStuckTransactions(provider, address) {
  const confirmedNonce = await provider.getTransactionCount(address, 'latest');
  const pendingNonce = await provider.getTransactionCount(address, 'pending');

  const pendingCount = pendingNonce - confirmedNonce;

  if (pendingCount === 0) {
    console.log('No pending transactions');
    return { status: 'clear', pendingCount: 0 };
  }

  console.log(`${pendingCount} pending transaction(s) detected`);
  console.log(`Confirmed nonce: ${confirmedNonce}`);
  console.log(`Pending nonce: ${pendingNonce}`);
  console.log(`Stuck nonces: ${confirmedNonce} to ${pendingNonce - 1}`);

  return {
    status: 'stuck',
    pendingCount,
    confirmedNonce,
    pendingNonce,
    stuckNonces: Array.from(
      { length: pendingCount },
      (_, i) => confirmedNonce + i
    )
  };
}

// Usage
const result = await detectStuckTransactions(provider, '0x78c1b0C915c4FAA5FffA6CAbf0219DA63d7f4cb8');
if (result.status === 'stuck') {
  console.log('Consider replacing transactions at nonces:', result.stuckNonces);
}

async function sendBatchTransactions(wallet, transactions) {
  const startNonce = await provider.getTransactionCount(
    wallet.address, 'pending'
  );

  console.log(`Sending ${transactions.length} transactions starting at nonce ${startNonce}`);

  const receipts = [];
  for (let i = 0; i < transactions.length; i++) {
    const nonce = startNonce + i;
    const tx = await wallet.sendTransaction({
      ...transactions[i],
      nonce
    });

    console.log(`Tx ${i + 1}/${transactions.length} sent: ${tx.hash} (nonce: ${nonce})`);
    receipts.push(tx);
  }

  // Wait for all to confirm
  const confirmed = await Promise.all(
    receipts.map(tx => tx.wait())
  );

  console.log(`All ${confirmed.length} transactions confirmed`);
  return confirmed;
}

// Usage
const transactions = [
  { to: '0xRecipient1...', value: parseEther('0.1') },
  { to: '0xRecipient2...', value: parseEther('0.2') },
  { to: '0xRecipient3...', value: parseEther('0.05') }
];

await sendBatchTransactions(wallet, transactions);

async function safeGetNonce(provider, address, maxRetries = 3) {
  for (let i = 0; i < maxRetries; i++) {
    try {
      return await provider.getTransactionCount(address, 'pending');
    } catch (error) {
      if (error.code === -32005) {
        await new Promise(r => setTimeout(r, Math.pow(2, i) * 1000));
        continue;
      }
      if (i === maxRetries - 1) throw error;
      await new Promise(r => setTimeout(r, Math.pow(2, i) * 1000));
    }
  }
}