Airdrop

{{
  "language": "Solidity",
  "sources": {
    "@openzeppelin/contracts/access/Ownable.sol": {
      "content": "// 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);
    }
}
"
    },
    "@openzeppelin/contracts/token/ERC20/IERC20.sol": {
      "content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.20;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
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);
}
"
    },
    "@openzeppelin/contracts/utils/Context.sol": {
      "content": "// 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;
    }
}
"
    },
    "@openzeppelin/contracts/utils/ReentrancyGuard.sol": {
      "content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (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 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;
    }
}
"
    },
    "contracts/Airdrop.sol": {
      "content": "// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

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

contract Airdrop is Ownable, ReentrancyGuard {
    // Token to be airdropped
    IERC20 public token;
    
    // Airdrop status
    bool public isAirdropActive;
    uint256 public totalAirdropped;
    uint256 public airdropStartTime;
    uint256 public airdropEndTime;
    
    // Airdrop limits
    uint256 public maxTokensPerAddress;
    uint256 public totalAirdropAmount;
    
    // Tracking
    mapping(address => bool) public hasClaimed;
    mapping(address => uint256) public claimedAmount;
    
    // Whitelist functionalitymaxTokensPerAddress
    mapping(address => bool) public whitelist;
    bool public isWhitelistEnabled;
    
    // Events
    event AirdropStarted(uint256 startTime, uint256 endTime, uint256 totalAmount);
    event AirdropEnded(uint256 totalDistributed);
    event TokensClaimed(address indexed recipient, uint256 amount);
    event TokensRecovered(address token, uint256 amount);
    event WhitelistStatusChanged(bool enabled);
    event AddressWhitelisted(address indexed account);
    event AddressRemovedFromWhitelist(address indexed account);
    
    constructor(address _token) Ownable(msg.sender) {
        require(_token != address(0), "Invalid token address");
        token = IERC20(_token);
        isWhitelistEnabled = false; // Whitelist is disabled by default
    }
    
    // Start a new airdrop
    function startAirdrop(
        uint256 _totalAmount,
        uint256 _maxTokensPerAddress,
        uint256 _durationInDays,
        bool _enableWhitelist
    ) external onlyOwner {
        require(!isAirdropActive, "Airdrop already active");
        require(_totalAmount > 0, "Invalid total amount");
        require(_maxTokensPerAddress > 0, "Invalid max tokens per address");
        require(_durationInDays > 0, "Invalid duration");
        
        // Transfer tokens to this contract
        require(
            token.transferFrom(msg.sender, address(this), _totalAmount),
            "Token transfer failed"
        );
        
        isAirdropActive = true;
        totalAirdropAmount = _totalAmount;
        maxTokensPerAddress = _maxTokensPerAddress;
        airdropStartTime = block.timestamp;
        airdropEndTime = block.timestamp + (_durationInDays * 1 days);
        isWhitelistEnabled = _enableWhitelist;
        
        emit AirdropStarted(airdropStartTime, airdropEndTime, _totalAmount);
        emit WhitelistStatusChanged(_enableWhitelist);
    }
    
    // End airdrop and recover remaining tokens
function endAirdrop() external onlyOwner {
    require(isAirdropActive, "No active airdrop");

    isAirdropActive = false;
    uint256 remainingTokens = token.balanceOf(address(this));

    if (remainingTokens > 0) {
        require(
            token.transfer(owner(), remainingTokens),
            "Token recovery failed"
        );
        emit TokensRecovered(address(token), remainingTokens);
    }
    
    uint256 totalDistributed = totalAirdropped;

    totalAirdropped = 0;
    isWhitelistEnabled = false;

    emit AirdropEnded(totalDistributed);
    emit WhitelistStatusChanged(false);
}

    
    // Claim airdrop tokens
    function claimTokens(uint256 amount) external nonReentrant {
        require(isAirdropActive, "Airdrop not active");
        require(block.timestamp >= airdropStartTime, "Airdrop not started");
        require(block.timestamp <= airdropEndTime, "Airdrop ended");
        require(!hasClaimed[msg.sender], "Already claimed");
        require(amount > 0, "Invalid amount");
        require(amount <= maxTokensPerAddress, "Amount exceeds limit");
        require(totalAirdropped + amount <= totalAirdropAmount, "Exceeds total airdrop amount");
        
        // Check whitelist if enabled
        if (isWhitelistEnabled) {
            require(whitelist[msg.sender], "Address not whitelisted");
        }
        
        hasClaimed[msg.sender] = true;
        claimedAmount[msg.sender] = amount;
        totalAirdropped += amount;
        
        require(
            token.transfer(msg.sender, amount),
            "Token transfer failed"
        );
        
        emit TokensClaimed(msg.sender, amount);
    }
    
    // Whitelist management functions
    function addToWhitelist(address[] calldata accounts) external onlyOwner {
        for (uint256 i = 0; i < accounts.length; i++) {
            require(accounts[i] != address(0), "Invalid address");
            whitelist[accounts[i]] = true;
            emit AddressWhitelisted(accounts[i]);
        }
    }
    
    function removeFromWhitelist(address[] calldata accounts) external onlyOwner {
        for (uint256 i = 0; i < accounts.length; i++) {
            whitelist[accounts[i]] = false;
            emit AddressRemovedFromWhitelist(accounts[i]);
        }
    }
    
    function toggleWhitelist(bool _enabled) external onlyOwner {
        isWhitelistEnabled = _enabled;
        emit WhitelistStatusChanged(_enabled);
    }
    
    // Batch airdrop to multiple addresses
    function batchAirdrop(
        address[] calldata recipients,
        uint256[] calldata amounts
    ) external onlyOwner nonReentrant {
        require(recipients.length == amounts.length, "Arrays length mismatch");
        require(isAirdropActive, "Airdrop not active");
        
        uint256 totalAmount = 0;
        for (uint256 i = 0; i < recipients.length; i++) {
            require(amounts[i] > 0, "Invalid amount");
            require(amounts[i] <= maxTokensPerAddress, "Amount exceeds limit");
            require(!hasClaimed[recipients[i]], "Address already claimed");
            
            // Check whitelist if enabled
            if (isWhitelistEnabled) {
                require(whitelist[recipients[i]], "Address not whitelisted");
            }
            
            hasClaimed[recipients[i]] = true;
            claimedAmount[recipients[i]] = amounts[i];
            totalAmount += amounts[i];
        }
        
        require(totalAirdropped + totalAmount <= totalAirdropAmount, "Exceeds total airdrop amount");
        totalAirdropped += totalAmount;
        
        for (uint256 i = 0; i < recipients.length; i++) {
            require(
                token.transfer(recipients[i], amounts[i]),
                "Token transfer failed"
            );
            emit TokensClaimed(recipients[i], amounts[i]);
        }
    }
    
    // View functions
    function getAirdropStatus() external view returns (
        bool active,
        uint256 startTime,
        uint256 endTime,
        uint256 totalAmount,
        uint256 distributedAmount,
        uint256 remainingAmount,
        bool whitelistEnabled
    ) {
        return (
            isAirdropActive,
            airdropStartTime,
            airdropEndTime,
            totalAirdropAmount,
            totalAirdropped,
            totalAirdropAmount - totalAirdropped,
            isWhitelistEnabled
        );
    }
    
    function canClaim(address user) external view returns (bool) {
        bool whitelistCheck = !isWhitelistEnabled || whitelist[user];
        return isAirdropActive && 
            !hasClaimed[user] && 
            block.timestamp >= airdropStartTime && 
            block.timestamp <= airdropEndTime &&
            whitelistCheck;
    }
}"
    }
  },
  "settings": {
    "optimizer": {
      "enabled": true,
      "runs": 1000000
    },
    "evmVersion": "paris",
    "outputSelection": {
      "*": {
        "*": [
          "evm.bytecode",
          "evm.deployedBytecode",
          "devdoc",
          "userdoc",
          "metadata",
          "abi"
        ]
      }
    }
  }
}}