Sophon Testnet

Contract Diff Checker

Contract Name:
DynamicRewards

Contract Source Code:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/access/AccessControl.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
import "@openzeppelin/contracts/utils/Pausable.sol";
import "./interfaces/IReclaim.sol";

/**
 * @title DynamicRewards
 * @dev A smart contract for managing social media post rewards with proof verification
 * 
 * This contract enables a reward system for social media posts where users can claim rewards
 * by proving their ownership of specific posts using zkTLS. The system supports
 * both native tokens (ETH) and ERC20 tokens as rewards.
 * 
 * Key Features:
 * - Dynamic limits for post IDsx and usernames
 * - Configurable bulk operation limits
 * - Support for both ETH and ERC20 token rewards
 * - zkTLS Proof-based verification using Reclaim Protocol
 * - Gas-optimized using bytes32 for storage
 * - Comprehensive event logging
 * - Role-based access control with admin capabilities
 * 
 * Security Features:
 * - String length restrictions to prevent DOS attacks
 * - Role-based access control for administrative functions
 * - Proof verification for claiming rewards
 * - Reentrancy protection for all external calls
 * - Pausable functionality for emergencies
 * - Emergency withdrawal capability
 * - Custom error messages for better debugging
 */
contract DynamicRewards is Ownable, AccessControl, ReentrancyGuard, Pausable {
    // Role definition for admins
    bytes32 public constant ADMIN_ROLE = keccak256("ADMIN_ROLE");
    bytes32 public constant REWARD_CREATOR_ROLE = keccak256("REWARD_CREATOR_ROLE");

    // Dynamic limits that can be adjusted by the owner
    uint256 public maxPostIdLength;      
    uint256 public maxUsernameLength;    
    uint256 public maxBulkOperations;    
    uint256 public defaultExpirationDuration;  

    // Custom Errors for better gas efficiency and clearer error messages
    error EmptyPostId();                 
    error ZeroAmount();                  
    error PostIdAlreadyRewarded();       
    error InvalidTokenAddress();         
    error IncorrectNativeTokenAmount();  
    error NativeTokenNotNeeded();        
    error InsufficientContractBalance(); 
    error TransferFailed();              
    error NoRewardAvailable();           
    error RewardAlreadyClaimed();        
    error InvalidProof();                
    error EmptyUsername();               
    error InvalidUsername();             
    error StringTooLong();               
    error RewardNotClaimable();          
    error ZeroAddress();                 
    error EmptyArray();                  
    error ArrayLengthMismatch();         
    error InvalidLength();               
    error ExceedsMaxBulkOperations();    
    error InvalidProofData();            
    error RewardExpired();               
    error InvalidExpiration();          
    error ProofVerificationFailed();     // New error for proof verification failure
    error UsernameVerificationFailed();  // New error for username verification failure

    /**
     * @dev Struct to store reward information
     * @param postId Original post ID for reference
     * @param username Username associated with the reward
     * @param token Address of the reward token (address(0) for ETH)
     * @param amount Amount of tokens to be rewarded
     * @param claimed Whether the reward has been claimed
     * @param claimable Whether the reward is still claimable (false if removed)
     * @param createdAt Timestamp when the reward was created
     * @param expiresAt Timestamp when the reward expires
     */
    struct Reward {
        string postId;      // Original post ID for reference
        string username;    // Username associated with the reward
        address token;      // Token address (address(0) for ETH)
        uint256 amount;     // Amount of tokens to reward
        bool claimed;       // Whether the reward has been claimed
        bool claimable;     // Whether the reward is still claimable
        uint256 createdAt;  // Timestamp when reward was created
        uint256 expiresAt;  // Timestamp when reward expires
    }

    // STATE VARIABLES
    /// @dev Address of the Reclaim Protocol verifier contract for proof validation
    address public reclaimAddress;
    
    /// @dev Mapping from keccak256(postId) to reward information
    /// @notice Using bytes32 instead of string for gas optimization
    mapping(bytes32 => Reward) public postRewards;

    // EVENTS
    /// @dev Emitted when a new reward is added
    /// @param postIdHash Hash of the post ID for efficient indexing
    /// @param postId Original post ID for readability
    event RewardAdded(
        bytes32 indexed postIdHash,
        string postId,
        address indexed token,
        uint256 amount
    );

    /// @dev Emitted when a reward is claimed
    /// @param postIdHash Hash of the post ID for efficient indexing
    /// @param postId Original post ID for readability
    event RewardClaimed(
        bytes32 indexed postIdHash,
        string postId,
        string username,
        address indexed token,
        uint256 amount
    );

    /// @dev Emitted when Reclaim verifier address is updated
    event ReclaimAddressUpdated(
        address indexed oldAddress,
        address indexed newAddress
    );

    /// @dev Emitted when a reward is removed
    event RewardRemoved(bytes32 indexed postIdHash, string postId);
    
    /// @dev Emitted when contract is paused/unpaused
    event ContractPaused(address indexed owner);
    event ContractUnpaused(address indexed owner);
    
    /// @dev Emitted when limits are updated
    event LimitsUpdated(
        uint256 maxPostIdLength,
        uint256 maxUsernameLength,
        uint256 maxBulkOperations
    );

    event AdminAdded(address indexed account);
    event RewardCreatorAdded(address indexed account);
    event AdminRemoved(address indexed account);
    event RewardCreatorRemoved(address indexed account);

    /**
     * @dev Contract constructor
     * @param initialOwner Address to be set as contract owner
     * @param reclaimAddress_ Address of Reclaim Protocol verifier
     * @param initialMaxPostIdLength Initial maximum length for post IDs
     * @param initialMaxUsernameLength Initial maximum length for usernames
     * @param initialMaxBulkOperations Initial maximum number of bulk operations
     * @param initialDefaultExpirationDuration Initial default duration in seconds for reward expiration
     */
    constructor(
        address initialOwner,
        address reclaimAddress_,
        uint256 initialMaxPostIdLength,
        uint256 initialMaxUsernameLength,
        uint256 initialMaxBulkOperations,
        uint256 initialDefaultExpirationDuration
    ) Ownable(initialOwner) {
        if (initialOwner == address(0)) revert ZeroAddress();
        if (reclaimAddress_ == address(0)) revert ZeroAddress();
        if (initialMaxPostIdLength == 0) revert InvalidLength();
        if (initialMaxUsernameLength == 0) revert InvalidLength();
        if (initialMaxBulkOperations == 0) revert InvalidLength();
        if (initialDefaultExpirationDuration == 0) revert InvalidLength();

        _grantRole(DEFAULT_ADMIN_ROLE, initialOwner);
        _grantRole(ADMIN_ROLE, initialOwner);

        reclaimAddress = reclaimAddress_;
        maxPostIdLength = initialMaxPostIdLength;
        maxUsernameLength = initialMaxUsernameLength;
        maxBulkOperations = initialMaxBulkOperations;
        defaultExpirationDuration = initialDefaultExpirationDuration;
    }

    /**
     * @dev Modifier that checks if the caller has admin privileges
     */
    modifier onlyAdminRole() {
        require(hasRole(ADMIN_ROLE, msg.sender) || owner() == msg.sender, "Caller is not an admin");
        _;
    }

        /**
     * @dev Modifier that checks if the caller has admin privileges
     */
    modifier onlyRewardCreatorRole() {
        require(hasRole(REWARD_CREATOR_ROLE, msg.sender) || hasRole(ADMIN_ROLE, msg.sender) || owner() == msg.sender, "Caller is not a reward creator");
        _;
    }

    /**
     * @dev Grants admin role to an account
     * @param account Address to grant admin role to
     */
    function grantAdminRole(address account) external onlyOwner {
        if (account == address(0)) revert ZeroAddress();
        _grantRole(ADMIN_ROLE, account);
        emit AdminAdded(account);
    }

        /**
     * @dev Grants reward creator role to an account
     * @param account Address to grant reward creator role to
     */
    function grantRewardCreatorRole(address account) external onlyAdminRole {
        if (account == address(0)) revert ZeroAddress();
        _grantRole(REWARD_CREATOR_ROLE, account);
        emit RewardCreatorAdded(account);
    }

    /**
     * @dev Revokes admin role from an account
     * @param account Address to revoke admin role from
     */
    function revokeAdminRole(address account) external onlyOwner {
        _revokeRole(ADMIN_ROLE, account);
        emit AdminRemoved(account);
    }

        /**
     * @dev Revokes reward creator role from an account
     * @param account Address to revoke reward creator role from
     */
    function revokeRewardCreatorRole(address account) external onlyOwner {
        _revokeRole(REWARD_CREATOR_ROLE, account);
        emit RewardCreatorRemoved(account);
    }

    /**
     * @dev Updates the system limits
     * @notice This function allows the owner to adjust the maximum lengths and bulk operation limits
     * @param newMaxPostIdLength New maximum length for post IDs
     * @param newMaxUsernameLength New maximum length for usernames
     * @param newMaxBulkOperations New maximum number of bulk operations
     */
    function updateLimits(
        uint256 newMaxPostIdLength,
        uint256 newMaxUsernameLength,
        uint256 newMaxBulkOperations
    ) external onlyAdminRole {
        if (newMaxPostIdLength == 0) revert InvalidLength();
        if (newMaxUsernameLength == 0) revert InvalidLength();
        if (newMaxBulkOperations == 0) revert InvalidLength();

        maxPostIdLength = newMaxPostIdLength;
        maxUsernameLength = newMaxUsernameLength;
        maxBulkOperations = newMaxBulkOperations;

        emit LimitsUpdated(newMaxPostIdLength, newMaxUsernameLength, newMaxBulkOperations);
    }

    function updateReclaimAddress(address newReclaimAddress) external onlyAdminRole {
        if (newReclaimAddress == address(0)) revert ZeroAddress();
        address oldAddress = reclaimAddress;
        reclaimAddress = newReclaimAddress;
        emit ReclaimAddressUpdated(oldAddress, newReclaimAddress);
    }

    function pause() external onlyAdminRole {
        _pause();
        emit ContractPaused(msg.sender);
    }

    function unpause() external onlyAdminRole {
        _unpause();
        emit ContractUnpaused(msg.sender);
    }

    /**
     * @dev Internal function to convert post ID to its hash
     * @param postId Original post ID
     * @return bytes32 Hash of the post ID
     */
    function _postIdToHash(string calldata postId) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked(postId));
    }

    /**
     * @dev Internal function to add a new reward
     * @notice Handles both ETH and ERC20 token rewards
     * @param postId Unique identifier of the post
     * @param username Username associated with the post
     * @param token Address of reward token (address(0) for ETH)
     * @param amount Amount of tokens to reward
     * @param expirationTimestamp Timestamp when the reward expires
     */
    function _addReward(
        string calldata postId,
        string calldata username,
        address token,
        uint256 amount,
        uint256 expirationTimestamp
    ) internal {
        if (amount == 0) revert ZeroAmount();
        if (bytes(postId).length == 0) revert EmptyPostId();
        if (bytes(username).length == 0) revert EmptyUsername();
        if (bytes(postId).length > maxPostIdLength) revert StringTooLong();
        if (bytes(username).length > maxUsernameLength) revert StringTooLong();

        bytes32 postIdHash = _postIdToHash(postId);
        if (postRewards[postIdHash].amount != 0) revert PostIdAlreadyRewarded();

        uint256 currentTime = block.timestamp;
        uint256 actualExpirationTimestamp;

        // If expiration is 0 or equal to creation time, use default duration
        if (expirationTimestamp == 0 || expirationTimestamp == currentTime) {
            actualExpirationTimestamp = currentTime + defaultExpirationDuration;
        } else {
            if (expirationTimestamp <= currentTime) revert InvalidExpiration();
            actualExpirationTimestamp = expirationTimestamp;
        }

        // Validate token address if it's an ERC20
        if (token != address(0)) {
            if (token == address(0)) revert ZeroAddress();
            if (IERC20(token).totalSupply() == 0) revert InvalidTokenAddress();
        }

        postRewards[postIdHash] = Reward({
            postId: postId,
            username: username,
            token: token,
            amount: amount,
            claimed: false,
            claimable: true,
            createdAt: currentTime,
            expiresAt: actualExpirationTimestamp
        });

        emit RewardAdded(postIdHash, postId, token, amount);
    }

    function addReward(
        string calldata postId,
        string calldata username,
        address token,
        uint256 amount,
        uint256 expirationTimestamp
    ) external onlyRewardCreatorRole whenNotPaused {
        _addReward(postId, username, token, amount, expirationTimestamp);
    }

    /**
     * @dev Adds multiple rewards in a single transaction
     * @notice This function optimizes gas usage for multiple reward additions
     * @param postIds Array of post IDs
     * @param usernames Array of usernames
     * @param tokens Array of token addresses
     * @param amounts Array of reward amounts
     * @param expirationTimestamps Array of expiration timestamps
     */
    function addBulkRewards(
        string[] calldata postIds,
        string[] calldata usernames,
        address[] calldata tokens,
        uint256[] calldata amounts,
        uint256[] calldata expirationTimestamps
    ) external onlyRewardCreatorRole whenNotPaused {
        uint256 length = postIds.length;
        if (length == 0) revert EmptyArray();
        if (length > maxBulkOperations) revert ExceedsMaxBulkOperations();
        if (length != usernames.length || length != tokens.length || length != amounts.length || length != expirationTimestamps.length) 
            revert ArrayLengthMismatch();

        for (uint256 i = 0; i < length; i++) {
            _addReward(postIds[i], usernames[i], tokens[i], amounts[i], expirationTimestamps[i]);
        }
    }

    function removeReward(
        string calldata postId,
        bool withTransfer
    ) external onlyAdminRole {
        bytes32 postIdHash = _postIdToHash(postId);
        Reward storage reward = postRewards[postIdHash];
        if (reward.amount == 0) revert NoRewardAvailable();
        if (reward.claimed) revert RewardAlreadyClaimed();
        
        if (withTransfer) {
            if (reward.token == address(0)) {
                (bool success, ) = msg.sender.call{value: reward.amount}("");
                if (!success) revert TransferFailed();
            } else {
                if (!IERC20(reward.token).transfer(msg.sender, reward.amount)) {
                    revert TransferFailed();
                }
            }
        }
        
        reward.claimable = false;
        emit RewardRemoved(postIdHash, postId);
    }

    function removeBulkRewards(
        string[] calldata postIds,
        bool withTransfer
    ) external onlyAdminRole {
        uint256 length = postIds.length;
        if (length == 0) revert EmptyArray();
        if (length > maxBulkOperations) revert ExceedsMaxBulkOperations();

        if (withTransfer) {
            uint256 totalNativeAmount;
            address[] memory tokenAddresses = new address[](length);
            uint256[] memory tokenAmounts = new uint256[](length);
            uint256 tokenCount;

            for (uint256 i = 0; i < length; i++) {
                bytes32 postIdHash = _postIdToHash(postIds[i]);
                Reward storage reward = postRewards[postIdHash];
                if (reward.amount == 0) revert NoRewardAvailable();
                if (reward.claimed) revert RewardAlreadyClaimed();
                if (!reward.claimable) revert RewardNotClaimable();

                if (reward.token == address(0)) {
                    totalNativeAmount += reward.amount;
                } else {
                    bool found = false;
                    for (uint256 j = 0; j < tokenCount; j++) {
                        if (tokenAddresses[j] == reward.token) {
                            tokenAmounts[j] += reward.amount;
                            found = true;
                            break;
                        }
                    }
                    if (!found) {
                        tokenAddresses[tokenCount] = reward.token;
                        tokenAmounts[tokenCount] = reward.amount;
                        tokenCount++;
                    }
                }
                reward.claimable = false;
            }

            if (totalNativeAmount > 0) {
                (bool success, ) = msg.sender.call{value: totalNativeAmount}("");
                if (!success) revert TransferFailed();
            }

            for (uint256 i = 0; i < tokenCount; i++) {
                if (!IERC20(tokenAddresses[i]).transfer(msg.sender, tokenAmounts[i])) {
                    revert TransferFailed();
                }
            }
        } else {
            for (uint256 i = 0; i < length; i++) {
                bytes32 postIdHash = _postIdToHash(postIds[i]);
                Reward storage reward = postRewards[postIdHash];
                if (reward.amount == 0) revert NoRewardAvailable();
                if (reward.claimed) revert RewardAlreadyClaimed();
                if (!reward.claimable) revert RewardNotClaimable();
                reward.claimable = false;
            }
        }

        for (uint256 i = 0; i < length; i++) {
            emit RewardRemoved(_postIdToHash(postIds[i]), postIds[i]);
        }
    }

    /**
     * @dev Claims a reward for a social media post
     * @notice Verifies proof using Reclaim Protocol before processing claim
     * @param postId ID of the post to claim reward for
     * @param username Username of the claimer
     * @param proof Proof of post ownership from Reclaim Protocol
     */
    function claimReward(
        string calldata postId,
        string calldata username,
        IReclaim.Proof memory proof
    ) external nonReentrant whenNotPaused {
        if (bytes(proof.claimInfo.context).length == 0) revert InvalidProofData();
        
        // Try to verify the proof, revert with custom error if it fails
        try IReclaim(reclaimAddress).verifyProof(proof) {
            bytes32 postIdHash = _postIdToHash(postId);
            Reward storage reward = postRewards[postIdHash];
            
            if (reward.amount == 0) revert NoRewardAvailable();
            if (reward.claimed) revert RewardAlreadyClaimed();
            if (!reward.claimable) revert RewardNotClaimable();
            if (block.timestamp > reward.expiresAt) revert RewardExpired();
            
            // Extract and verify username
            string memory proofUsername;
            try IReclaim(reclaimAddress).extractFieldFromContext(
                proof.claimInfo.context,
                '"screen_name":"'
            ) returns (string memory extractedUsername) {
                proofUsername = extractedUsername;
            } catch {
                revert UsernameVerificationFailed();
            }
            
            if (keccak256(abi.encodePacked(proofUsername)) != keccak256(abi.encodePacked(username))) 
                revert InvalidUsername();

            reward.claimed = true;

            if (reward.token == address(0)) {
                if (address(this).balance < reward.amount) revert InsufficientContractBalance();
                (bool success, ) = msg.sender.call{value: reward.amount}("");
                if (!success) revert TransferFailed();
            } else {
                IERC20 token = IERC20(reward.token);
                if (token.balanceOf(address(this)) < reward.amount) revert InsufficientContractBalance();
                if (!token.transfer(msg.sender, reward.amount)) revert TransferFailed();
            }

            emit RewardClaimed(postIdHash, postId, username, reward.token, reward.amount);
        } catch {
            revert ProofVerificationFailed();
        }
    }

    function getReward(
        string calldata postId
    ) external view returns (Reward memory) {
        return postRewards[_postIdToHash(postId)];
    }

    /**
     * @dev Emergency withdrawal function
     * @notice Allows owner to withdraw tokens in case of emergency
     * @param token Address of token to withdraw (address(0) for ETH)
     * @param amount Amount to withdraw
     */
    function emergencyWithdraw(
        address token,
        uint256 amount
    ) external onlyAdminRole {
        if (amount == 0) revert ZeroAmount();
        if (token == address(0)) {
            if (address(this).balance < amount) revert InsufficientContractBalance();
            (bool success, ) = msg.sender.call{value: amount}("");
            if (!success) revert TransferFailed();
        } else {
            IERC20 tokenContract = IERC20(token);
            if (tokenContract.balanceOf(address(this)) < amount) revert InsufficientContractBalance();
            if (!tokenContract.transfer(msg.sender, amount)) revert TransferFailed();
        }
    }

    /**
     * @dev Updates the default expiration duration
     * @param newDefaultExpirationDuration New default duration in seconds
     */
    function updateDefaultExpirationDuration(uint256 newDefaultExpirationDuration) external onlyAdminRole {
        if (newDefaultExpirationDuration == 0) revert InvalidLength();
        defaultExpirationDuration = newDefaultExpirationDuration;
    }

    /// @dev Allows contract to receive ETH
    receive() external payable {}
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

interface IReclaim {
    struct CompleteClaimData {
        bytes32 identifier;
        address owner;
        uint32 timestampS;
        uint32 epoch;
    }

    struct ClaimInfo {
        string provider;
        string parameters;
        string context;
    }

    struct SignedClaim {
        CompleteClaimData claim;
        bytes[] signatures;
    }

    struct Proof {
        ClaimInfo claimInfo;
        SignedClaim signedClaim;
    }

    function verifyProof(Proof memory proof) external view;

    function extractFieldFromContext(
        string memory data,
        string memory target
    ) external pure returns (string memory);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (access/AccessControl.sol)

pragma solidity ^0.8.20;

import {IAccessControl} from "./IAccessControl.sol";
import {Context} from "../utils/Context.sol";
import {ERC165} from "../utils/introspection/ERC165.sol";

/**
 * @dev Contract module that allows children to implement role-based access
 * control mechanisms. This is a lightweight version that doesn't allow enumerating role
 * members except through off-chain means by accessing the contract event logs. Some
 * applications may benefit from on-chain enumerability, for those cases see
 * {AccessControlEnumerable}.
 *
 * Roles are referred to by their `bytes32` identifier. These should be exposed
 * in the external API and be unique. The best way to achieve this is by
 * using `public constant` hash digests:
 *
 * ```solidity
 * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
 * ```
 *
 * Roles can be used to represent a set of permissions. To restrict access to a
 * function call, use {hasRole}:
 *
 * ```solidity
 * function foo() public {
 *     require(hasRole(MY_ROLE, msg.sender));
 *     ...
 * }
 * ```
 *
 * Roles can be granted and revoked dynamically via the {grantRole} and
 * {revokeRole} functions. Each role has an associated admin role, and only
 * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
 *
 * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
 * that only accounts with this role will be able to grant or revoke other
 * roles. More complex role relationships can be created by using
 * {_setRoleAdmin}.
 *
 * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
 * grant and revoke this role. Extra precautions should be taken to secure
 * accounts that have been granted it. We recommend using {AccessControlDefaultAdminRules}
 * to enforce additional security measures for this role.
 */
abstract contract AccessControl is Context, IAccessControl, ERC165 {
    struct RoleData {
        mapping(address account => bool) hasRole;
        bytes32 adminRole;
    }

    mapping(bytes32 role => RoleData) private _roles;

    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;

    /**
     * @dev Modifier that checks that an account has a specific role. Reverts
     * with an {AccessControlUnauthorizedAccount} error including the required role.
     */
    modifier onlyRole(bytes32 role) {
        _checkRole(role);
        _;
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);
    }

    /**
     * @dev Returns `true` if `account` has been granted `role`.
     */
    function hasRole(bytes32 role, address account) public view virtual returns (bool) {
        return _roles[role].hasRole[account];
    }

    /**
     * @dev Reverts with an {AccessControlUnauthorizedAccount} error if `_msgSender()`
     * is missing `role`. Overriding this function changes the behavior of the {onlyRole} modifier.
     */
    function _checkRole(bytes32 role) internal view virtual {
        _checkRole(role, _msgSender());
    }

    /**
     * @dev Reverts with an {AccessControlUnauthorizedAccount} error if `account`
     * is missing `role`.
     */
    function _checkRole(bytes32 role, address account) internal view virtual {
        if (!hasRole(role, account)) {
            revert AccessControlUnauthorizedAccount(account, role);
        }
    }

    /**
     * @dev Returns the admin role that controls `role`. See {grantRole} and
     * {revokeRole}.
     *
     * To change a role's admin, use {_setRoleAdmin}.
     */
    function getRoleAdmin(bytes32 role) public view virtual returns (bytes32) {
        return _roles[role].adminRole;
    }

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     *
     * May emit a {RoleGranted} event.
     */
    function grantRole(bytes32 role, address account) public virtual onlyRole(getRoleAdmin(role)) {
        _grantRole(role, account);
    }

    /**
     * @dev Revokes `role` from `account`.
     *
     * If `account` had been granted `role`, emits a {RoleRevoked} event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     *
     * May emit a {RoleRevoked} event.
     */
    function revokeRole(bytes32 role, address account) public virtual onlyRole(getRoleAdmin(role)) {
        _revokeRole(role, account);
    }

    /**
     * @dev Revokes `role` from the calling account.
     *
     * Roles are often managed via {grantRole} and {revokeRole}: this function's
     * purpose is to provide a mechanism for accounts to lose their privileges
     * if they are compromised (such as when a trusted device is misplaced).
     *
     * If the calling account had been revoked `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `callerConfirmation`.
     *
     * May emit a {RoleRevoked} event.
     */
    function renounceRole(bytes32 role, address callerConfirmation) public virtual {
        if (callerConfirmation != _msgSender()) {
            revert AccessControlBadConfirmation();
        }

        _revokeRole(role, callerConfirmation);
    }

    /**
     * @dev Sets `adminRole` as ``role``'s admin role.
     *
     * Emits a {RoleAdminChanged} event.
     */
    function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
        bytes32 previousAdminRole = getRoleAdmin(role);
        _roles[role].adminRole = adminRole;
        emit RoleAdminChanged(role, previousAdminRole, adminRole);
    }

    /**
     * @dev Attempts to grant `role` to `account` and returns a boolean indicating if `role` was granted.
     *
     * Internal function without access restriction.
     *
     * May emit a {RoleGranted} event.
     */
    function _grantRole(bytes32 role, address account) internal virtual returns (bool) {
        if (!hasRole(role, account)) {
            _roles[role].hasRole[account] = true;
            emit RoleGranted(role, account, _msgSender());
            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Attempts to revoke `role` to `account` and returns a boolean indicating if `role` was revoked.
     *
     * Internal function without access restriction.
     *
     * May emit a {RoleRevoked} event.
     */
    function _revokeRole(bytes32 role, address account) internal virtual returns (bool) {
        if (hasRole(role, account)) {
            _roles[role].hasRole[account] = false;
            emit RoleRevoked(role, account, _msgSender());
            return true;
        } else {
            return false;
        }
    }
}

// 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
// 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 v5.0.0) (utils/Pausable.sol)

pragma solidity ^0.8.20;

import {Context} from "../utils/Context.sol";

/**
 * @dev Contract module which allows children to implement an emergency stop
 * mechanism that can be triggered by an authorized account.
 *
 * This module is used through inheritance. It will make available the
 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
 * the functions of your contract. Note that they will not be pausable by
 * simply including this module, only once the modifiers are put in place.
 */
abstract contract Pausable is Context {
    bool private _paused;

    /**
     * @dev Emitted when the pause is triggered by `account`.
     */
    event Paused(address account);

    /**
     * @dev Emitted when the pause is lifted by `account`.
     */
    event Unpaused(address account);

    /**
     * @dev The operation failed because the contract is paused.
     */
    error EnforcedPause();

    /**
     * @dev The operation failed because the contract is not paused.
     */
    error ExpectedPause();

    /**
     * @dev Initializes the contract in unpaused state.
     */
    constructor() {
        _paused = false;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    modifier whenNotPaused() {
        _requireNotPaused();
        _;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    modifier whenPaused() {
        _requirePaused();
        _;
    }

    /**
     * @dev Returns true if the contract is paused, and false otherwise.
     */
    function paused() public view virtual returns (bool) {
        return _paused;
    }

    /**
     * @dev Throws if the contract is paused.
     */
    function _requireNotPaused() internal view virtual {
        if (paused()) {
            revert EnforcedPause();
        }
    }

    /**
     * @dev Throws if the contract is not paused.
     */
    function _requirePaused() internal view virtual {
        if (!paused()) {
            revert ExpectedPause();
        }
    }

    /**
     * @dev Triggers stopped state.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }

    /**
     * @dev Returns to normal state.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
}

// 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 v5.1.0) (access/IAccessControl.sol)

pragma solidity ^0.8.20;

/**
 * @dev External interface of AccessControl declared to support ERC-165 detection.
 */
interface IAccessControl {
    /**
     * @dev The `account` is missing a role.
     */
    error AccessControlUnauthorizedAccount(address account, bytes32 neededRole);

    /**
     * @dev The caller of a function is not the expected one.
     *
     * NOTE: Don't confuse with {AccessControlUnauthorizedAccount}.
     */
    error AccessControlBadConfirmation();

    /**
     * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
     *
     * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
     * {RoleAdminChanged} not being emitted signaling this.
     */
    event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);

    /**
     * @dev Emitted when `account` is granted `role`.
     *
     * `sender` is the account that originated the contract call. This account bears the admin role (for the granted role).
     * Expected in cases where the role was granted using the internal {AccessControl-_grantRole}.
     */
    event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Emitted when `account` is revoked `role`.
     *
     * `sender` is the account that originated the contract call:
     *   - if using `revokeRole`, it is the admin role bearer
     *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
     */
    event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Returns `true` if `account` has been granted `role`.
     */
    function hasRole(bytes32 role, address account) external view returns (bool);

    /**
     * @dev Returns the admin role that controls `role`. See {grantRole} and
     * {revokeRole}.
     *
     * To change a role's admin, use {AccessControl-_setRoleAdmin}.
     */
    function getRoleAdmin(bytes32 role) external view returns (bytes32);

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function grantRole(bytes32 role, address account) external;

    /**
     * @dev Revokes `role` from `account`.
     *
     * If `account` had been granted `role`, emits a {RoleRevoked} event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function revokeRole(bytes32 role, address account) external;

    /**
     * @dev Revokes `role` from the calling account.
     *
     * Roles are often managed via {grantRole} and {revokeRole}: this function's
     * purpose is to provide a mechanism for accounts to lose their privileges
     * if they are compromised (such as when a trusted device is misplaced).
     *
     * If the calling account had been granted `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `callerConfirmation`.
     */
    function renounceRole(bytes32 role, address callerConfirmation) external;
}

// 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/introspection/ERC165.sol)

pragma solidity ^0.8.20;

import {IERC165} from "./IERC165.sol";

/**
 * @dev Implementation of the {IERC165} interface.
 *
 * Contracts that want to implement ERC-165 should inherit from this contract and override {supportsInterface} to check
 * for the additional interface id that will be supported. For example:
 *
 * ```solidity
 * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
 *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
 * }
 * ```
 */
abstract contract ERC165 is IERC165 {
    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual returns (bool) {
        return interfaceId == type(IERC165).interfaceId;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (utils/introspection/IERC165.sol)

pragma solidity ^0.8.20;

/**
 * @dev Interface of the ERC-165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[ERC].
 *
 * Implementers can declare support of contract interfaces, which can then be
 * queried by others ({ERC165Checker}).
 *
 * For an implementation, see {ERC165}.
 */
interface IERC165 {
    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[ERC section]
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

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