I have the source below. When I receive Ethereum through this, I will pay the tokens accordingly. However, when I send Ethereum, only Ethereum is sent. How to fix it?
/**
*Submitted for verification at Etherscan.io on 2021-02-05
*/
pragma solidity ^0.4.24;
// ----------------------------------------------------------------------------
// @Name SafeMath
// @Desc Math operations with safety checks that throw on error
// https://github.com/OpenZeppelin/zeppelin-solidity/blob/master/contracts/math/SafeMath.sol
// ----------------------------------------------------------------------------
library SafeMath {
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
uint256 c = a * b;
assert(c / a == b);
return c;
}
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return a / b;
}
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b <= a);
return a - b;
}
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
assert(c >= a);
return c;
}
}
// ----------------------------------------------------------------------------
// @Name ERC20 interface
// @Desc https://eips.ethereum.org/EIPS/eip-20
// ----------------------------------------------------------------------------
interface IERC20 {
function totalSupply() external view returns (uint256);
function balanceOf(address account) external view returns (uint256);
function transfer(address recipient, uint256 amount) external returns (bool);
function allowance(address owner, address spender) external view returns (uint256);
function approve(address spender, uint256 amount) external returns (bool);
function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
event Transfer(address indexed from, address indexed to, uint256 value);
}
// ----------------------------------------------------------------------------
// @Name Ownable
// ----------------------------------------------------------------------------
contract Ownable {
address public owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
constructor() public {
owner = msg.sender;
}
modifier onlyOwner() { require(msg.sender == owner); _; }
function transferOwnership(address _newOwner) external onlyOwner {
require(_newOwner != address(0));
emit OwnershipTransferred(owner, _newOwner);
owner = _newOwner;
}
}
// ----------------------------------------------------------------------------
// ----------------------------------------------------------------------------
contract RewardPool is Ownable {
event eventChangeOwnerAddress(address previousOwner, address newOwner);
event eventChangeTokenCAEvent(address previousCA, address newCA);
event eventChangeRewardAmountEvent(uint256 indexed previousAmount, uint256 indexed newAmount);
event eventFundTransfer(address backer, uint256 amount);
event eventTokenWithdrawEvent(address withdrawAddress, uint256 amount);
using SafeMath for uint256;
IERC20 private TOKEN_CONTRACT_ADDRESS;
address public OWNER_ADDRESS;
uint256 public REWARD_RATE;
constructor() public {
TOKEN_CONTRACT_ADDRESS = IERC20(0xBcF5522b26eaEd7B929154f9b44364dFC2143A01);
REWARD_RATE = 5000000000000000000;
OWNER_ADDRESS = 0x9D2b30FB5EE941Cb59AE71Bb7Ef1C6f06dfeB6c7;
}
function () payable public {
uint256 amount = msg.value;
amount = amount.mul(REWARD_RATE);
require(amount <= TOKEN_CONTRACT_ADDRESS.balanceOf(this));
address(OWNER_ADDRESS).transfer(msg.value);
tokenTransfer(amount);
}
function withdrawToken(address _to, uint256 _amount) external onlyOwner {
require(TOKEN_CONTRACT_ADDRESS.transfer(_to, _amount));
emit eventTokenWithdrawEvent(_to, _amount);
}
function changeTokenAddress(IERC20 _tokenCA) external onlyOwner {
require(_tokenCA != address(0));
emit eventChangeTokenCAEvent(TOKEN_CONTRACT_ADDRESS, _tokenCA);
TOKEN_CONTRACT_ADDRESS = _tokenCA;
}
// 1 ETH : _amount Token
function changeRewardRate(uint256 _rate) external onlyOwner {
emit eventChangeRewardAmountEvent(REWARD_RATE, _rate);
REWARD_RATE = _rate;
}
function changOwnerAddress(address _ownerAddress) external onlyOwner {
emit eventChangeOwnerAddress(OWNER_ADDRESS, _ownerAddress);
OWNER_ADDRESS = _ownerAddress;
}
function tokenTransfer(uint256 _amount) internal {
require(TOKEN_CONTRACT_ADDRESS.transfer(msg.sender, _amount));
emit eventFundTransfer(msg.sender, _amount);
}
}
