Cryo Explorer Ethereum Mainnet

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;

import "openzeppelin-contracts/contracts/token/ERC20/utils/SafeERC20.sol";
import "openzeppelin-contracts/contracts/security/ReentrancyGuard.sol";
import "../interfaces/IExchangeConfig.sol";
import "./interfaces/IAirdrop.sol";


// The Airdrop contract keeps track of users who qualify for the Salty.IO Airdrop.
// The amount of awarded SALT for each user will be claimable over 52 weeks (starting from when allowClaiming() is called)

contract Airdrop is IAirdrop, ReentrancyGuard
    {
	using SafeERC20 for ISalt;

    uint256 constant VESTING_PERIOD = 52 weeks;

	IExchangeConfig immutable public exchangeConfig;
    ISalt immutable public salt;

	// The timestamp when allowClaiming() was called
	uint256 public claimingStartTimestamp;

	// A previous deployment that should be referenced
	IAirdrop public previousDeployment;

	// The claimable airdrop amount for each user
	mapping (address=>uint256) _airdropPerUser;

	// The amount already claimed by each user
	mapping (address=>uint256) claimedPerUser;


	constructor( IExchangeConfig _exchangeConfig, IAirdrop _previousDeployment )
		{
		exchangeConfig = _exchangeConfig;
		previousDeployment = _previousDeployment;

		salt = _exchangeConfig.salt();
		}


	// Authorize the wallet as being able to claim a specific amount of the airdrop.
	// The BootstrapBallot would have already confirmed the user is authorized to receive the specified saltAmount.
    function authorizeWallet( address wallet, uint256 saltAmount ) external
    	{
    	require( msg.sender == address(exchangeConfig.initialDistribution().bootstrapBallot()), "Only the BootstrapBallot can call Airdrop.authorizeWallet" );
    	require( claimingStartTimestamp == 0, "Cannot authorize after claiming is allowed" );
    	require( _airdropPerUser[wallet] == 0, "Wallet already authorized" );

		_airdropPerUser[wallet] = saltAmount;
    	}


	// Called to signify that users are able to start claiming their airdrop
    function allowClaiming() external
    	{
    	require( msg.sender == address(exchangeConfig.initialDistribution().bootstrapBallot()), "Only the BootstrapBallot can call Airdrop.allowClaiming" );
    	require( claimingStartTimestamp == 0, "Claiming is already allowed" );

		claimingStartTimestamp = block.timestamp;
    	}


	// Allow the user to claim up to the vested amount they are entitled to
    function claim() external nonReentrant
    	{
  		uint256 claimableSALT = claimableAmount(msg.sender);
    	require( claimableSALT != 0, "User has no claimable airdrop at this time" );

		// Send SALT to the user
		salt.safeTransfer( msg.sender, claimableSALT);

		// Remember the amount that was claimed by the user
		claimedPerUser[msg.sender] += claimableSALT;
    	}


    // === VIEWS ===

	// Whether or not claiming is allowed
	function claimingAllowed() public view returns (bool)
		{
		return claimingStartTimestamp != 0;
		}


	// The amount that the user has already claimed
	function claimedByUser( address wallet) public view returns (uint256)
		{
		return claimedPerUser[wallet];
		}


	// The amount of SALT that is currently claimable for the user
    function claimableAmount(address wallet) public view returns (uint256)
    	{
    	// Claiming not allowed yet?
    	if ( claimingStartTimestamp == 0 )
    		return 0;

    	// Look up the airdrop amount for the user
		uint256 airdropAmount = airdropForUser(wallet);
		if ( airdropAmount == 0 )
			return 0;

		uint256 timeElapsed = block.timestamp - claimingStartTimestamp;
		uint256 vestedAmount = ( airdropAmount * timeElapsed) / VESTING_PERIOD;

		// Don't exceed the airdropAmount
		if ( vestedAmount > airdropAmount )
			vestedAmount = airdropAmount;

		// Users can claim the vested amount they are entitled to minus the amount they have already claimed
		return vestedAmount - claimedPerUser[wallet];
    	}


    // The total airdrop that the user will receive
    function airdropForUser( address wallet ) public view returns (uint256)
    	{
    	// Use the previousDeployment if specified
  		if ( address(previousDeployment) != address(0) )
			return previousDeployment.airdropForUser(wallet);

    	return _airdropPerUser[wallet];
    	}
	}

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;

import "openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";


interface ISalt is IERC20
	{
	function burnTokensInContract() external;

	// Views
	function totalBurned() external view returns (uint256);
	}

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;


interface IUpkeep
	{
	function performUpkeep() external;

	// Views
	function currentRewardsForCallingPerformUpkeep() external view returns (uint256);
	function lastUpkeepTimeEmissions() external view returns (uint256);
	function lastUpkeepTimeRewardsEmitters() external view returns (uint256);
	}

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;

import "../../rewards/interfaces/ISaltRewards.sol";
import "../../pools/interfaces/IPools.sol";
import "../../interfaces/ISalt.sol";

interface IDAO
	{
	function finalizeBallot( uint256 ballotID ) external;
	function manuallyRemoveBallot( uint256 ballotID ) external;

	function withdrawFromDAO( IERC20 token ) external returns (uint256 withdrawnAmount);

	// Views
	function pools() external view returns (IPools);
	function websiteURL() external view returns (string memory);
	function countryIsExcluded( string calldata country ) external view returns (bool);
	}

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;

import "../../staking/interfaces/ILiquidity.sol";
import "../../dao/interfaces/IDAO.sol";
import "./IPoolStats.sol";


interface IPools is IPoolStats
	{
	function startExchangeApproved() external;
	function setContracts( IDAO _dao, ILiquidity _liquidity ) external; // onlyOwner

	function addLiquidity( IERC20 tokenA, IERC20 tokenB, uint256 maxAmountA, uint256 maxAmountB, uint256 minAddedAmountA, uint256 minAddedAmountB, uint256 totalLiquidity ) external returns (uint256 addedAmountA, uint256 addedAmountB, uint256 addedLiquidity);
	function removeLiquidity( IERC20 tokenA, IERC20 tokenB, uint256 liquidityToRemove, uint256 minReclaimedA, uint256 minReclaimedB, uint256 totalLiquidity ) external returns (uint256 reclaimedA, uint256 reclaimedB);

	function deposit( IERC20 token, uint256 amount ) external;
	function withdraw( IERC20 token, uint256 amount ) external;
	function swap( IERC20 swapTokenIn, IERC20 swapTokenOut, uint256 swapAmountIn, uint256 minAmountOut, uint256 deadline ) external returns (uint256 swapAmountOut);
	function depositSwapWithdraw(IERC20 swapTokenIn, IERC20 swapTokenOut, uint256 swapAmountIn, uint256 minAmountOut, uint256 deadline ) external returns (uint256 swapAmountOut);
	function depositDoubleSwapWithdraw( IERC20 swapTokenIn, IERC20 swapTokenMiddle, IERC20 swapTokenOut, uint256 swapAmountIn, uint256 minAmountOut, uint256 deadline ) external returns (uint256 swapAmountOut);
	function depositZapSwapWithdraw(IERC20 swapTokenIn, IERC20 swapTokenOut, uint256 swapAmountIn ) external returns (uint256 swapAmountOut);

	// Views
	function exchangeIsLive() external view returns (bool);
	function getPoolReserves(IERC20 tokenA, IERC20 tokenB) external view returns (uint256 reserveA, uint256 reserveB);
	function depositedUserBalance(address user, IERC20 token) external view returns (uint256);
	}

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;


interface IAccessManager
	{
	function excludedCountriesUpdated() external;
	function grantAccess(bytes calldata signature) external;

	// Views
	function geoVersion() external view returns (uint256);
	function walletHasAccess(address wallet) external view returns (bool);
	}

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;

import "openzeppelin-contracts/contracts/finance/VestingWallet.sol";
import "../staking/interfaces/ILiquidity.sol";
import "../launch/interfaces/IInitialDistribution.sol";
import "../rewards/interfaces/IRewardsEmitter.sol";
import "../rewards/interfaces/ISaltRewards.sol";
import "../rewards/interfaces/IEmissions.sol";
import "../interfaces/IAccessManager.sol";
import "../launch/interfaces/IAirdrop.sol";
import "../dao/interfaces/IDAO.sol";
import "../interfaces/ISalt.sol";
import "./IUpkeep.sol";


interface IExchangeConfig
	{
	function setContracts( IDAO _dao, IUpkeep _upkeep, IInitialDistribution _initialDistribution, VestingWallet _teamVestingWallet, VestingWallet _daoVestingWallet ) external; // onlyOwner
	function setAccessManager( IAccessManager _accessManager ) external; // onlyOwner

	// Views
	function salt() external view returns (ISalt);
	function wbtc() external view returns (IERC20);
	function weth() external view returns (IERC20);
	function usdc() external view returns (IERC20);
	function usdt() external view returns (IERC20);

	function daoVestingWallet() external view returns (VestingWallet);
    function teamVestingWallet() external view returns (VestingWallet);
    function initialDistribution() external view returns (IInitialDistribution);

	function accessManager() external view returns (IAccessManager);
	function dao() external view returns (IDAO);
	function upkeep() external view returns (IUpkeep);
	function teamWallet() external view returns (address);

	function walletHasAccess( address wallet ) external view returns (bool);
	}

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;


interface IAirdrop
	{
	function authorizeWallet( address wallet, uint256 saltAmount ) external;
	function allowClaiming() external;
	function claim() external;

	// Views
	function claimedByUser( address wallet) external view returns (uint256);
	function claimingAllowed() external view returns (bool);
	function claimingStartTimestamp() external view returns (uint256);
	function claimableAmount(address wallet) external view returns (uint256);
    function airdropForUser( address wallet ) external view returns (uint256);
	}

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;


interface IPoolStats
	{
	// These are the indicies (in terms of a poolIDs location in the current whitelistedPoolIDs array) of pools involved in an arbitrage path
	struct ArbitrageIndicies
		{
		uint64 index1;
		uint64 index2;
		uint64 index3;
		}

	function clearProfitsForPools() external;
	function updateArbitrageIndicies() external;

	// Views
	function profitsForWhitelistedPools() external view returns (uint256[] memory _calculatedProfits);
	function arbitrageIndicies(bytes32 poolID) external view returns (ArbitrageIndicies memory);
	}

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;


interface IEmissions
	{
	function performUpkeep( uint256 timeSinceLastUpkeep ) external;
    }

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;

import "openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";
import "./IStakingRewards.sol";


interface ILiquidity is IStakingRewards
	{
	function depositLiquidityAndIncreaseShare( IERC20 tokenA, IERC20 tokenB, uint256 maxAmountA, uint256 maxAmountB, uint256 minAddedAmountA, uint256 minAddedAmountB, uint256 minAddedLiquidity, uint256 deadline, bool useZapping ) external returns (uint256 addedLiquidity);
	function withdrawLiquidityAndClaim( IERC20 tokenA, IERC20 tokenB, uint256 liquidityToWithdraw, uint256 minReclaimedA, uint256 minReclaimedB, uint256 deadline ) external returns (uint256 reclaimedA, uint256 reclaimedB);
	}

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;

import "./IRewardsEmitter.sol";


interface ISaltRewards
	{
	function sendInitialSaltRewards( uint256 liquidityBootstrapAmount, bytes32[] calldata poolIDs ) external;
    function performUpkeep( bytes32[] calldata poolIDs, uint256[] calldata profitsForPools ) external;

    // Views
    function stakingRewardsEmitter() external view returns (IRewardsEmitter);
    function liquidityRewardsEmitter() external view returns (IRewardsEmitter);
    }

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;


interface IBootstrapBallot
	{
	function vote( bool voteStartExchangeYes, uint256 saltAmount, bytes calldata signature ) external;
	function finalizeBallot() external;

	function authorizeAirdrop2( uint256 saltAmount, bytes calldata signature ) external;
	function finalizeAirdrop2() external;

	// Views
	function claimableTimestamp1() external view returns (uint256);
	function claimableTimestamp2() external view returns (uint256);

	function hasVoted(address user) external view returns (bool);
	function ballotFinalized() external view returns (bool);

	function startExchangeYes() external view returns (uint256);
	function startExchangeNo() external view returns (uint256);
	}

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;

import "../../staking/interfaces/IStakingRewards.sol";


interface IRewardsEmitter
	{
	function addSALTRewards( AddedReward[] calldata addedRewards ) external;
	function performUpkeep( uint256 timeSinceLastUpkeep ) external;

	// Views
	function pendingRewardsForPools( bytes32[] calldata pools ) external view returns (uint256[] calldata);
	}

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;


struct AddedReward
	{
	bytes32 poolID;							// The pool to add rewards to
	uint256 amountToAdd;				// The amount of rewards (as SALT) to add
	}

struct UserShareInfo
	{
	uint256 userShare;					// A user's share for a given poolID
	uint256 virtualRewards;				// The amount of rewards that were added to maintain proper rewards/share ratio - and will be deducted from a user's pending rewards.
	uint256 cooldownExpiration;		// The timestamp when the user can modify their share
	}


interface IStakingRewards
	{
	function claimAllRewards( bytes32[] calldata poolIDs ) external returns (uint256 rewardsAmount);
	function addSALTRewards( AddedReward[] calldata addedRewards ) external;

	// Views
	function totalShares(bytes32 poolID) external view returns (uint256);
	function totalSharesForPools( bytes32[] calldata poolIDs ) external view returns (uint256[] calldata shares);
	function totalRewardsForPools( bytes32[] calldata poolIDs ) external view returns (uint256[] calldata rewards);

	function userRewardForPool( address wallet, bytes32 poolID ) external view returns (uint256);
	function userShareForPool( address wallet, bytes32 poolID ) external view returns (uint256);
	function userVirtualRewardsForPool( address wallet, bytes32 poolID ) external view returns (uint256);

	function userRewardsForPools( address wallet, bytes32[] calldata poolIDs ) external view returns (uint256[] calldata rewards);
	function userShareForPools( address wallet, bytes32[] calldata poolIDs ) external view returns (uint256[] calldata shares);
	function userCooldowns( address wallet, bytes32[] calldata poolIDs ) external view returns (uint256[] calldata cooldowns);
	}

// SPDX-License-Identifier: BUSL 1.1
pragma solidity =0.8.22;

import "./IBootstrapBallot.sol";
import "./IAirdrop.sol";


interface IInitialDistribution
	{
	function distributionApproved( IAirdrop airdrop1, IAirdrop airdrop2 ) external;

	// Views
	function bootstrapBallot() external view returns (IBootstrapBallot);
	}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)

pragma solidity ^0.8.1;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     *
     * Furthermore, `isContract` will also return true if the target contract within
     * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
     * which only has an effect at the end of a transaction.
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://consensys.net/diligence/blog/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // Look for revert reason and bubble it up if present
        if (returndata.length > 0) {
            // The easiest way to bubble the revert reason is using memory via assembly
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @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;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @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 amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` 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 amount) 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 `amount` 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 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` 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 amount) external returns (bool);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (finance/VestingWallet.sol)
pragma solidity ^0.8.0;

import "../token/ERC20/utils/SafeERC20.sol";
import "../utils/Address.sol";
import "../utils/Context.sol";

/**
 * @title VestingWallet
 * @dev This contract handles the vesting of Eth and ERC20 tokens for a given beneficiary. Custody of multiple tokens
 * can be given to this contract, which will release the token to the beneficiary following a given vesting schedule.
 * The vesting schedule is customizable through the {vestedAmount} function.
 *
 * Any token transferred to this contract will follow the vesting schedule as if they were locked from the beginning.
 * Consequently, if the vesting has already started, any amount of tokens sent to this contract will (at least partly)
 * be immediately releasable.
 */
contract VestingWallet is Context {
    event EtherReleased(uint256 amount);
    event ERC20Released(address indexed token, uint256 amount);

    uint256 private _released;
    mapping(address => uint256) private _erc20Released;
    address private immutable _beneficiary;
    uint64 private immutable _start;
    uint64 private immutable _duration;

    /**
     * @dev Set the beneficiary, start timestamp and vesting duration of the vesting wallet.
     */
    constructor(address beneficiaryAddress, uint64 startTimestamp, uint64 durationSeconds) payable {
        require(beneficiaryAddress != address(0), "VestingWallet: beneficiary is zero address");
        _beneficiary = beneficiaryAddress;
        _start = startTimestamp;
        _duration = durationSeconds;
    }

    /**
     * @dev The contract should be able to receive Eth.
     */
    receive() external payable virtual {}

    /**
     * @dev Getter for the beneficiary address.
     */
    function beneficiary() public view virtual returns (address) {
        return _beneficiary;
    }

    /**
     * @dev Getter for the start timestamp.
     */
    function start() public view virtual returns (uint256) {
        return _start;
    }

    /**
     * @dev Getter for the vesting duration.
     */
    function duration() public view virtual returns (uint256) {
        return _duration;
    }

    /**
     * @dev Amount of eth already released
     */
    function released() public view virtual returns (uint256) {
        return _released;
    }

    /**
     * @dev Amount of token already released
     */
    function released(address token) public view virtual returns (uint256) {
        return _erc20Released[token];
    }

    /**
     * @dev Getter for the amount of releasable eth.
     */
    function releasable() public view virtual returns (uint256) {
        return vestedAmount(uint64(block.timestamp)) - released();
    }

    /**
     * @dev Getter for the amount of releasable `token` tokens. `token` should be the address of an
     * IERC20 contract.
     */
    function releasable(address token) public view virtual returns (uint256) {
        return vestedAmount(token, uint64(block.timestamp)) - released(token);
    }

    /**
     * @dev Release the native token (ether) that have already vested.
     *
     * Emits a {EtherReleased} event.
     */
    function release() public virtual {
        uint256 amount = releasable();
        _released += amount;
        emit EtherReleased(amount);
        Address.sendValue(payable(beneficiary()), amount);
    }

    /**
     * @dev Release the tokens that have already vested.
     *
     * Emits a {ERC20Released} event.
     */
    function release(address token) public virtual {
        uint256 amount = releasable(token);
        _erc20Released[token] += amount;
        emit ERC20Released(token, amount);
        SafeERC20.safeTransfer(IERC20(token), beneficiary(), amount);
    }

    /**
     * @dev Calculates the amount of ether that has already vested. Default implementation is a linear vesting curve.
     */
    function vestedAmount(uint64 timestamp) public view virtual returns (uint256) {
        return _vestingSchedule(address(this).balance + released(), timestamp);
    }

    /**
     * @dev Calculates the amount of tokens that has already vested. Default implementation is a linear vesting curve.
     */
    function vestedAmount(address token, uint64 timestamp) public view virtual returns (uint256) {
        return _vestingSchedule(IERC20(token).balanceOf(address(this)) + released(token), timestamp);
    }

    /**
     * @dev Virtual implementation of the vesting formula. This returns the amount vested, as a function of time, for
     * an asset given its total historical allocation.
     */
    function _vestingSchedule(uint256 totalAllocation, uint64 timestamp) internal view virtual returns (uint256) {
        if (timestamp < start()) {
            return 0;
        } else if (timestamp > start() + duration()) {
            return totalAllocation;
        } else {
            return (totalAllocation * (timestamp - start())) / duration();
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (security/ReentrancyGuard.sol)

pragma solidity ^0.8.0;

/**
 * @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;

    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
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // 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 v4.9.3) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

import "../IERC20.sol";
import "../extensions/IERC20Permit.sol";
import "../../../utils/Address.sol";

/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using Address for address;

    /**
     * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    /**
     * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
     * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
     */
    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    /**
     * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 oldAllowance = token.allowance(address(this), spender);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
    }

    /**
     * @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
        }
    }

    /**
     * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
     * to be set to zero before setting it to a non-zero value, such as USDT.
     */
    function forceApprove(IERC20 token, address spender, uint256 value) internal {
        bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);

        if (!_callOptionalReturnBool(token, approvalCall)) {
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
            _callOptionalReturn(token, approvalCall);
        }
    }

    /**
     * @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
     * Revert on invalid signature.
     */
    function safePermit(
        IERC20Permit token,
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        uint256 nonceBefore = token.nonces(owner);
        token.permit(owner, spender, value, deadline, v, r, s);
        uint256 nonceAfter = token.nonces(owner);
        require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address-functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        require(returndata.length == 0 || abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     *
     * This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
     */
    function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We cannot use {Address-functionCall} here since this should return false
        // and not revert is the subcall reverts.

        (bool success, bytes memory returndata) = address(token).call(data);
        return
            success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/extensions/IERC20Permit.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);

    /**
     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}