DestChainReceiver.sol

// SPDX-License-Identifier: MIT
pragma solidity 0.8.19;

import {IRouterClient} from "@chainlink/contracts-ccip/src/v0.8/ccip/interfaces/IRouterClient.sol";
import {OwnerIsCreator} from "@chainlink/contracts-ccip/src/v0.8/shared/access/OwnerIsCreator.sol";
import {Client} from "@chainlink/contracts-ccip/src/v0.8/ccip/libraries/Client.sol";
import {CCIPReceiver} from "@chainlink/contracts-ccip/src/v0.8/ccip/applications/CCIPReceiver.sol";
import {IERC20} from "@chainlink/contracts-ccip/src/v0.8/vendor/openzeppelin-solidity/v4.8.3/contracts/token/ERC20/IERC20.sol";
import {SafeERC20} from "@chainlink/contracts-ccip/src/v0.8/vendor/openzeppelin-solidity/v4.8.3/contracts/token/ERC20/utils/SafeERC20.sol";

/**
 * THIS IS AN EXAMPLE CONTRACT THAT USES HARDCODED VALUES FOR CLARITY.
 * THIS IS AN EXAMPLE CONTRACT THAT USES UN-AUDITED CODE.
 * DO NOT USE THIS CODE IN PRODUCTION.
 */

/// @title - A simple messenger contract for transferring/receiving tokens and data across chains.
contract DestChainReceiver is CCIPReceiver, OwnerIsCreator {
    using SafeERC20 for IERC20;

    address public routerEthSepolia = 0x0BF3dE8c5D3e8A2B34D2BEeB17ABfCeBaf363A59;
    address public BnMToken = 0xFd57b4ddBf88a4e07fF4e34C487b99af2Fe82a05;

    // Custom errors to provide more descriptive revert messages.
    error NotEnoughBalance(uint256 currentBalance, uint256 calculatedFees); // Used to make sure contract has enough balance to cover the fees.
    error NothingToWithdraw(); // Used when trying to withdraw Ether but there's nothing to withdraw.
    error FailedToWithdrawEth(address owner, address target, uint256 value); // Used when the withdrawal of Ether fails.

    bytes32 private s_lastReceivedMessageId; // Store the last received messageId.
    address private s_lastReceivedTokenAddress; // Store the last received token address.
    uint256 private s_lastReceivedTokenAmount; // Store the last received amount.
    string private s_lastReceivedText; // Store the last received text.

    /// @notice Constructor initializes the contract with the router address.
    constructor() CCIPReceiver(routerEthSepolia) {}

    /**
     * @notice Returns the details of the last CCIP received message.
     * @dev This function retrieves the ID, text, token address, and token amount of the last received CCIP message.
     * @return messageId The ID of the last received CCIP message.
     * @return text The text of the last received CCIP message.
     * @return tokenAddress The address of the token in the last CCIP received message.
     * @return tokenAmount The amount of the token in the last CCIP received message.
     */
    function getLastReceivedMessageDetails()
        public
        view
        returns (
            bytes32 messageId,
            string memory text,
            address tokenAddress,
            uint256 tokenAmount
        )
    {
        return (
            s_lastReceivedMessageId,
            s_lastReceivedText,
            s_lastReceivedTokenAddress,
            s_lastReceivedTokenAmount
        );
    }

    /// handle a received message
    function _ccipReceive(
        Client.Any2EVMMessage memory any2EvmMessage
    )
        internal
        override
    {
        s_lastReceivedMessageId = any2EvmMessage.messageId; // fetch the messageId
        s_lastReceivedText = abi.decode(any2EvmMessage.data, (string)); // abi-decoding of the sent text
        // Expect one token to be transferred at once, but you can transfer several tokens.
        s_lastReceivedTokenAddress = any2EvmMessage.destTokenAmounts[0].token;
        s_lastReceivedTokenAmount = any2EvmMessage.destTokenAmounts[0].amount;
    }

    function currentBalance() public view returns (uint256 balance){
        balance = IERC20(BnMToken).balanceOf(address(this));
    }

    /// @notice Allows the owner of the contract to withdraw all tokens of a specific ERC20 token.
    /// @dev This function reverts with a 'NothingToWithdraw' error if there are no tokens to withdraw.
    /// @param _beneficiary The address to which the tokens will be sent.
    /// @param _token The contract address of the ERC20 token to be withdrawn.
    function withdrawToken(
        address _beneficiary,
        address _token
    ) public onlyOwner {
        uint256 amount = IERC20(_token).balanceOf(address(this));
        if (amount == 0) revert NothingToWithdraw();
        IERC20(_token).safeTransfer(_beneficiary, amount);
    }
}