Contract Source Code:
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol)
pragma solidity ^0.8.20;
import {Context} from "../utils/Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* The initial owner is set to the address provided by the deployer. This can
* later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
/**
* @dev The caller account is not authorized to perform an operation.
*/
error OwnableUnauthorizedAccount(address account);
/**
* @dev The owner is not a valid owner account. (eg. `address(0)`)
*/
error OwnableInvalidOwner(address owner);
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the address provided by the deployer as the initial owner.
*/
constructor(address initialOwner) {
if (initialOwner == address(0)) {
revert OwnableInvalidOwner(address(0));
}
_transferOwnership(initialOwner);
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
_checkOwner();
_;
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if the sender is not the owner.
*/
function _checkOwner() internal view virtual {
if (owner() != _msgSender()) {
revert OwnableUnauthorizedAccount(_msgSender());
}
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby disabling any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
if (newOwner == address(0)) {
revert OwnableInvalidOwner(address(0));
}
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.20;
/**
* @dev Interface of the ERC-20 standard as defined in the ERC.
*/
interface IERC20 {
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
/**
* @dev Returns the value of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the value of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves a `value` amount of tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, uint256 value) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets a `value` amount of tokens as the allowance of `spender` over the
* caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 value) external returns (bool);
/**
* @dev Moves a `value` amount of tokens from `from` to `to` using the
* allowance mechanism. `value` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(address from, address to, uint256 value) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.1) (utils/Context.sol)
pragma solidity ^0.8.20;
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
function _contextSuffixLength() internal view virtual returns (uint256) {
return 0;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (utils/ReentrancyGuard.sol)
pragma solidity ^0.8.20;
/**
* @dev Contract module that helps prevent reentrant calls to a function.
*
* Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
* available, which can be applied to functions to make sure there are no nested
* (reentrant) calls to them.
*
* Note that because there is a single `nonReentrant` guard, functions marked as
* `nonReentrant` may not call one another. This can be worked around by making
* those functions `private`, and then adding `external` `nonReentrant` entry
* points to them.
*
* TIP: If EIP-1153 (transient storage) is available on the chain you're deploying at,
* consider using {ReentrancyGuardTransient} instead.
*
* TIP: If you would like to learn more about reentrancy and alternative ways
* to protect against it, check out our blog post
* https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
*/
abstract contract ReentrancyGuard {
// Booleans are more expensive than uint256 or any type that takes up a full
// word because each write operation emits an extra SLOAD to first read the
// slot's contents, replace the bits taken up by the boolean, and then write
// back. This is the compiler's defense against contract upgrades and
// pointer aliasing, and it cannot be disabled.
// The values being non-zero value makes deployment a bit more expensive,
// but in exchange the refund on every call to nonReentrant will be lower in
// amount. Since refunds are capped to a percentage of the total
// transaction's gas, it is best to keep them low in cases like this one, to
// increase the likelihood of the full refund coming into effect.
uint256 private constant NOT_ENTERED = 1;
uint256 private constant ENTERED = 2;
uint256 private _status;
/**
* @dev Unauthorized reentrant call.
*/
error ReentrancyGuardReentrantCall();
constructor() {
_status = NOT_ENTERED;
}
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* Calling a `nonReentrant` function from another `nonReentrant`
* function is not supported. It is possible to prevent this from happening
* by making the `nonReentrant` function external, and making it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
_nonReentrantBefore();
_;
_nonReentrantAfter();
}
function _nonReentrantBefore() private {
// On the first call to nonReentrant, _status will be NOT_ENTERED
if (_status == ENTERED) {
revert ReentrancyGuardReentrantCall();
}
// Any calls to nonReentrant after this point will fail
_status = ENTERED;
}
function _nonReentrantAfter() private {
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = NOT_ENTERED;
}
/**
* @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
* `nonReentrant` function in the call stack.
*/
function _reentrancyGuardEntered() internal view returns (bool) {
return _status == ENTERED;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.7;
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
import {IGelatoChecker} from "../interfaces/IGelatoChecker.sol";
import {ICharity} from "../interfaces/ICharity.sol";
contract Charity is Ownable, ReentrancyGuard, IGelatoChecker, ICharity {
/** state variables */
bool public canWithdrawFunds = true;
Category public charityCategory;
address public automationBot = address(0);
/** constants */
address public constant ETH_ADDRESS = address(0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE);
/** errors */
error Charity__InsufficientBalance();
error Charity__SendingFailed();
error Charity__WithdrawalDisabled();
error Charity__TokenAlreadyWhitelisted();
error Charity__TokenNotWhitelisted();
error Charity__MustBeAutomatedOrOwner(address caller);
/**
* mappings
*/
mapping(address => bool) private whitelistedTokens;
/**
* arrays
*/
address[] private tokenList;
enum Category {
Education,
Health,
Environment,
Animals,
HumanRights,
Poverty,
Other
}
modifier onlyAutomationOrOwner() {
if (msg.sender != automationBot && msg.sender != owner()) {
revert Charity__MustBeAutomatedOrOwner(msg.sender);
}
_;
}
/** events */
event DonationWithdrawn(address indexed organization, address indexed token, uint256 amount);
event TokenWhitelisted(address token);
event TokenRemoved(address token);
constructor(Category _category) Ownable(msg.sender) {
charityCategory = _category;
}
/**
* @dev Set the automation bot address.
* @param _automation address of the automation bot
*/
function setAutomationBot(address _automation) external onlyOwner {
automationBot = _automation;
}
/**
* @dev Check if the contract can withdraw funds.
*/
function canWithdraw() external view returns (bool) {
return canWithdrawFunds;
}
/**
* @dev Set the status of the contract to withdraw funds.
* @param status The status to set.
*/
function setCanWithdraw(bool status) external onlyOwner {
canWithdrawFunds = status;
}
/**
* @dev Adds a token to the whitelist.
* @param token The address of the token to add.
*/
function addWhitelistedToken(address token) external onlyOwner {
if (whitelistedTokens[token]) {
revert Charity__TokenAlreadyWhitelisted();
}
whitelistedTokens[token] = true;
tokenList.push(token);
emit TokenWhitelisted(token);
}
/**
* @dev Removes a token from the whitelist.
* @param token The address of the token to remove.
*/
function removeWhitelistedToken(address token) external onlyOwner {
if (!whitelistedTokens[token]) {
revert Charity__TokenNotWhitelisted();
}
whitelistedTokens[token] = false;
for (uint256 i = 0; i < tokenList.length; i++) {
if (tokenList[i] == token) {
tokenList[i] = tokenList[tokenList.length - 1];
tokenList.pop();
break;
}
}
emit TokenRemoved(token);
}
/**
* @dev Returns the list of whitelisted ERC-20 tokens.
*/
function getWhitelistedTokens() public view returns (address[] memory) {
return tokenList;
}
/**
* Automates funds distribution to the organization.
* @return canExec - whether the contract can execute the withdrawal
* @return execPayload - the payload to execute the withdrawal
*/
function checker() external view returns (bool canExec, bytes memory execPayload) {
address organization = owner();
uint256 ethBalance = address(this).balance;
if (!canWithdrawFunds) {
return (false, abi.encode("Withdrawals Disabled"));
}
if (ethBalance > 0) {
return (
true,
abi.encodeCall(
ICharity.withdrawToOrganization,
(ETH_ADDRESS, ethBalance, organization)
)
);
}
address[] memory tokens = getWhitelistedTokens();
for (uint256 i = 0; i < tokens.length; i++) {
uint256 tokenBalance = IERC20(tokens[i]).balanceOf(address(this));
if (tokenBalance > 0) {
return (
true,
abi.encodeCall(
ICharity.withdrawToOrganization,
(tokens[i], tokenBalance, organization)
)
);
}
}
return (false, abi.encode("No Funds Available"));
}
/**
* @dev Check the balance of the contract.
* @param token The address of the token to check the balance of.
* @return The balance of the contract.
*/
function balanceOf(address token) external view returns (uint256) {
if (token == ETH_ADDRESS) {
return address(this).balance;
} else {
return IERC20(token).balanceOf(address(this));
}
}
/**
* @dev Withdraw the donation from the contract.
* @param token The address of the token to withdraw.
* @param amount The amount to withdraw.
* @param organization The address to send the funds to.
*/
function withdrawToOrganization(
address token,
uint256 amount,
address organization
) external onlyAutomationOrOwner nonReentrant {
if (!canWithdrawFunds) {
revert Charity__WithdrawalDisabled();
}
if (token == ETH_ADDRESS) {
if (address(this).balance < amount) {
revert Charity__SendingFailed();
}
(bool success, ) = organization.call{value: amount}("");
if (!success) {
revert Charity__SendingFailed();
}
} else {
if (!whitelistedTokens[token]) {
revert Charity__TokenNotWhitelisted();
}
bool sendSuccess = IERC20(token).transfer(organization, amount);
if (!sendSuccess) {
revert Charity__SendingFailed();
}
}
emit DonationWithdrawn(organization, token, amount);
}
/**
* @dev Fallback function to receive ETH donations.
*/
receive() external payable {}
}
// SPDX-License-Identifier: UNLICENSED
pragma solidity >=0.8.0;
interface ICharity {
function withdrawToOrganization(address token, uint256 amount, address organization) external;
}
// SPDX-License-Identifier: UNLICENSED
pragma solidity >=0.8.0;
interface IGelatoChecker {
function checker() external view returns (bool canExec, bytes memory execPayload);
}