Complete EVM Wallet Delegation

import { ethers } from 'ethers';

function generateSIWEMessage(address, chainId) {
  const domain = window.location.host;
  const now = new Date();
  const expirationTime = new Date(now.getTime() + 30 * 60000); // 30 minutes

  const nonce = ethers.utils.hexlify(ethers.utils.randomBytes(16));

  const message = `Website x wants you to sign in with your Ethereum account:
${address}

Prove address ownership

URI: ${domain}
Version: 1
Chain ID: ${chainId}
Nonce: ${nonce}
Issued At: ${now.toISOString()}
Expiration Time: ${expirationTime.toISOString()}`;

  return message;
}

// Usage
const provider = new ethers.providers.Web3Provider(window.ethereum);
const signer = await provider.getSigner();
const address = await signer.getAddress();
const network = await provider.getNetwork();

const message = generateSIWEMessage(address, network.chainId);
const signature = await signer.signMessage(message);

import { ethers } from 'ethers';

async function delegateEVMWallet(delegationToken, amount, network = 'linea') {
  try {
    // Step 1: Connect wallet
    const provider = new ethers.providers.Web3Provider(window.ethereum);
    await provider.send('eth_requestAccounts', []);
    const signer = await provider.getSigner();
    const address = await signer.getAddress();
    const networkInfo = await provider.getNetwork();

    console.log(`Connected to ${address} on chain ${networkInfo.chainId}`);

    // Step 2: Request token approval
    const tokenAddress = getTokenAddress(network, 'usdc');
    const spenderAddress = getPlatformSpenderAddress(network);

    const tokenContract = new ethers.Contract(
      tokenAddress,
      ['function approve(address spender, uint256 amount) returns (bool)'],
      signer
    );

    const amountInWei = ethers.utils.parseUnits(amount, 6); // USDC has 6 decimals
    const tx = await tokenContract.approve(spenderAddress, amountInWei);

    console.log('Approval transaction sent:', tx.hash);
    const receipt = await tx.wait();
    console.log('Approval confirmed in block:', receipt.blockNumber);

    // Step 3: Generate and sign SIWE message
    const siweMessage = generateSIWEMessage(address, networkInfo.chainId);
    const signature = await signer.signMessage(siweMessage);

    console.log('Message signed successfully');

    // Step 4: Submit to API
    const response = await fetch(
      'https://dev.api.baanx.com/v1/delegation/evm/post-approval',
      {
        method: 'POST',
        headers: {
          'x-client-key': 'YOUR_PUBLIC_KEY',
          'Authorization': 'Bearer YOUR_ACCESS_TOKEN',
          'Content-Type': 'application/json'
        },
        body: JSON.stringify({
          address: address,
          network: network,
          currency: 'usdc',
          amount: amount,
          txHash: receipt.transactionHash,
          sigHash: signature,
          sigMessage: siweMessage,
          token: delegationToken
        })
      }
    );

    const result = await response.json();

    if (response.ok) {
      console.log('Delegation completed successfully!');
      return { success: true, data: result };
    } else {
      console.error('Delegation failed:', result);
      return { success: false, error: result };
    }

  } catch (error) {
    console.error('Error during delegation:', error);
    return { success: false, error: error.message };
  }
}

// Helper functions
function getTokenAddress(network, currency) {
  const addresses = {
    linea: {
      usdc: '0x176211869cA2b568f2A7D4EE941E073a821EE1ff',
      usdt: '0xA219439258ca9da29E9Cc4cE5596924745e12B93'
    },
    ethereum: {
      usdc: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
      usdt: '0xdAC17F958D2ee523a2206206994597C13D831ec7'
    }
  };
  return addresses[network][currency];
}

function getPlatformSpenderAddress(network) {
  // Replace with actual platform spender addresses
  const spenders = {
    linea: '0x...',
    ethereum: '0x...'
  };
  return spenders[network];
}

function generateSIWEMessage(address, chainId) {
  const domain = window.location.host;
  const now = new Date();
  const expirationTime = new Date(now.getTime() + 30 * 60000);
  const nonce = ethers.utils.hexlify(ethers.utils.randomBytes(16));

  return `Website x wants you to sign in with your Ethereum account:
${address}

Prove address ownership

URI: ${domain}
Version: 1
Chain ID: ${chainId}
Nonce: ${nonce}
Issued At: ${now.toISOString()}
Expiration Time: ${expirationTime.toISOString()}`;
}

curl --request GET \
  --url 'https://dev.api.baanx.com/v1/wallet/external' \
  --header 'x-client-key: YOUR_PUBLIC_KEY' \
  --header 'Authorization: Bearer YOUR_ACCESS_TOKEN'