// File: contracts/TokenSalePool.sol



// SPDX-License-Identifier: agpl-3.0
pragma solidity ^0.8.0;

import "./interfaces/ITokenSalePool.sol";
import "./interfaces/IDistributor.sol";
import "./utils/Operators.sol";
import "./tokensale/TokenSale.sol";

contract TokenSalePool is ITokenSalePool, Operators {
    mapping(string => ITokenSalePool.Pool) public poolInfo;
    string[] public poolIds;

    mapping(string => bool) public poolExists;

    function createPool(
        string calldata _poolID,
        string calldata _poolName,
        uint256 _poolCreationTime
    ) external override onlyOperator {
        require(!poolExists[_poolID], "Pool ID already existed");
        IDistributor distributor;
        ITokenSale tokenSale = new TokenSale();

        poolInfo[_poolID] = Pool({
            poolID: _poolID,
            poolName: _poolName,
            poolCreationTime: _poolCreationTime,
            tokenSale: tokenSale,
            distributor: distributor
        });
        poolExists[_poolID] = true;
        poolIds.push(_poolID);
    }

    function setDistributor(string calldata _poolID, IDistributor _distributor)
        external
        override
        onlyOperator
    {
        poolInfo[_poolID].distributor = _distributor;
    }

    function setCampaign(
        string calldata _poolID,
        string calldata _campaignID,
        bytes32 _merkleRoot,
        uint64 _startTime,
        uint64 _endTime,
        uint256 _srcCap,
        uint256 _dstCap,
        IERC20 _acceptToken,
        IERC20 _token
    ) external override onlyOperator {
        return
            poolInfo[_poolID].tokenSale.setCampaign(
                _campaignID,
                _merkleRoot,
                _startTime,
                _endTime,
                _srcCap,
                _dstCap,
                _acceptToken,
                _token
            );
    }

    function setCampaignToken(
        string calldata _poolID,
        string calldata _campaignID,
        IERC20 _token
    ) external override onlyOperator {
        poolInfo[_poolID].tokenSale.setCampaignToken(_campaignID, _token);
    }

    function setCampaignTokenOfPool(string calldata _poolID, IERC20 _token)
        external
        override
        onlyOperator
    {
        string[] memory campaignIDs = getCampaignIds(_poolID);
        for (uint32 i = 0; i < campaignIDs.length; i++) {
            poolInfo[_poolID].tokenSale.setCampaignToken(
                campaignIDs[i],
                _token
            );
        }
    }

    function buy(
        string calldata _poolID,
        string calldata _campaignID,
        uint128 _index,
        uint256 _maxCap,
        uint256 _amount,
        bytes32[] calldata _merkleProof
    ) external payable override {
        poolInfo[_poolID].tokenSale.buy{value: msg.value}(
            _campaignID,
            _index,
            _maxCap,
            _amount,
            _merkleProof
        );
    }

    function withdrawSaleFund(
        string calldata _poolID,
        string calldata _campaignID,
        address _to
    ) external override onlyOwner {
        poolInfo[_poolID].tokenSale.withdrawSaleFund(_campaignID, _to);
    }

    function withdrawSaleFundOfPool(string calldata _poolID, address _to)
        external
        override
        onlyOwner
    {
        string[] memory campaignIDs = getCampaignIds(_poolID);
        for (uint32 i = 0; i < campaignIDs.length; i++) {
            poolInfo[_poolID].tokenSale.withdrawSaleFund(campaignIDs[i], _to);
        }
    }

    function emergencyWithdraw(
        string calldata _poolID,
        IERC20 _token,
        address _to,
        uint256 _amount
    ) external override onlyOwner {
        poolInfo[_poolID].tokenSale.emergencyWithdraw(_token, _to, _amount);
    }

    function getUserInfo(
        string calldata _poolID,
        string calldata _campaignID,
        address _user
    ) external view override returns (ITokenSale.UserInfo memory) {
        return poolInfo[_poolID].tokenSale.getUserInfo(_campaignID, _user);
    }

    function getCampaign(string calldata _poolID, string calldata _campaignID)
        external
        view
        override
        returns (ITokenSale.Campaign memory)
    {
        return poolInfo[_poolID].tokenSale.getCampaign(_campaignID);
    }

    function getCampaignIds(string calldata _poolID)
        public
        view
        override
        returns (string[] memory)
    {
        return poolInfo[_poolID].tokenSale.getCampaignIds();
    }

    function getTokenSaleContractAddress(string calldata _poolID)
        external
        view
        override
        returns (address)
    {
        return address(poolInfo[_poolID].tokenSale);
    }

    function getDistributorAddress(string calldata _poolID)
        external
        view
        override
        returns (address)
    {
        return address(poolInfo[_poolID].distributor);
    }
}

// File: contracts/interfaces/ITokenSalePool.sol



// SPDX-License-Identifier: agpl-3.0
pragma solidity ^0.8.0;

import "@openzeppelin/contracts/interfaces/IERC20.sol";
import "./ITokenSale.sol";
import "./IDistributor.sol";

interface ITokenSalePool {
    struct Pool {
        string poolID;
        string poolName;
        uint256 poolCreationTime;
        ITokenSale tokenSale;
        IDistributor distributor;
    }

    function createPool(
        string calldata _poolID,
        string calldata _poolName,
        uint256 _poolCreationTime
    ) external;

    function setDistributor(string calldata _poolID, IDistributor _distributor)
        external;

    function setCampaign(
        string calldata _poolID,
        string calldata _campaignID,
        bytes32 _merkleRoot,
        uint64 _startTime,
        uint64 _endTime,
        uint256 _srcCap,
        uint256 _dstCap,
        IERC20 _acceptToken,
        IERC20 _token
    ) external;

    function setCampaignToken(
        string calldata _poolID,
        string calldata _campaignID,
        IERC20 _token
    ) external;

    function setCampaignTokenOfPool(string calldata _poolID, IERC20 _token)
        external;

    function buy(
        string calldata _poolID,
        string calldata _campaignID,
        uint128 _index,
        uint256 _maxCap,
        uint256 _amount,
        bytes32[] calldata _merkleProof
    ) external payable;

    function withdrawSaleFund(
        string calldata _poolID,
        string calldata _campaignID,
        address _to
    ) external;

    function withdrawSaleFundOfPool(string calldata _poolID, address _to)
        external;

    function emergencyWithdraw(
        string calldata _poolID,
        IERC20 _token,
        address _to,
        uint256 _amount
    ) external;

    function getUserInfo(
        string calldata _poolID,
        string calldata _campaignID,
        address _user
    ) external view returns (ITokenSale.UserInfo memory);

    function getCampaignIds(string calldata _poolID)
        external
        view
        returns (string[] memory);

    function getCampaign(string calldata _poolID, string calldata _campaignID)
        external
        view
        returns (ITokenSale.Campaign memory);

    function getTokenSaleContractAddress(string calldata _poolID)
        external
        view
        returns (address);

    function getDistributorAddress(string calldata _poolID)
        external
        view
        returns (address);
}

// File: contracts/interfaces/IDistributor.sol



// SPDX-License-Identifier: agpl-3.0
pragma solidity ^0.8.0;

import "@openzeppelin/contracts/interfaces/IERC20.sol";

interface IDistributor {
    enum TrancheType {
        ONCE,
        LINEAR
    }

    function setReleaseInfo(
        string calldata _campaignID,
        uint256[] calldata _trancheStartTimestamps,
        uint256[] calldata _trancheEndTimestamps,
        uint32[] calldata _percentageOfTranches,
        TrancheType[] calldata _trancheTypes
    ) external;

    function withdraw(string calldata _campaignID) external;

    function emergencyWithdraw(
        IERC20 _token,
        address _to,
        uint256 _amount
    ) external;

    function getWithdrawableAmount(string calldata _campaignID, address _user)
        external
        view
        returns (uint256);

    function getWithdrawedAmount(string calldata _campaignID, address _user)
        external
        view
        returns (uint256);
}

// File: contracts/utils/Operators.sol



// SPDX-License-Identifier: agpl-3.0
pragma solidity ^0.8.0;

import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
import {EnumerableSet} from "@openzeppelin/contracts/utils/structs/EnumerableSet.sol";

contract Operators is Ownable {
    using EnumerableSet for EnumerableSet.AddressSet;

    EnumerableSet.AddressSet operators;

    event OperatorsAdded(address[] _operators);
    event OperatorsRemoved(address[] _operators);

    constructor() {}

    modifier onlyOperator() {
        require(
            isOperator(_msgSender()) || (owner() == _msgSender()),
            "caller is not operator"
        );
        _;
    }

    function addOperators(address[] calldata _operators) external onlyOwner {
        for (uint256 i = 0; i < _operators.length; i++) {
            operators.add(_operators[i]);
        }
        emit OperatorsAdded(_operators);
    }

    function removeOperators(address[] calldata _operators) external onlyOwner {
        for (uint256 i = 0; i < _operators.length; i++) {
            operators.remove(_operators[i]);
        }
        emit OperatorsRemoved(_operators);
    }

    function isOperator(address _operator) public view returns (bool) {
        return operators.contains(_operator);
    }

    function numberOperators() external view returns (uint256) {
        return operators.length();
    }

    function operatorAt(uint256 i) external view returns (address) {
        return operators.at(i);
    }

    function getAllOperators()
        external
        view
        returns (address[] memory _operators)
    {
        _operators = new address[](operators.length());
        for (uint256 i = 0; i < _operators.length; i++) {
            _operators[i] = operators.at(i);
        }
    }
}

// File: contracts/tokensale/TokenSale.sol



// SPDX-License-Identifier: agpl-3.0
pragma solidity ^0.8.0;

import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "@openzeppelin/contracts/utils/cryptography/MerkleProof.sol";
import "@openzeppelin/contracts/utils/structs/EnumerableSet.sol";

import "@openzeppelin/contracts/access/Ownable.sol";
import "../interfaces/ITokenSale.sol";

contract TokenSale is ITokenSale, Ownable, ReentrancyGuard {
    using SafeERC20 for IERC20;
    using EnumerableSet for EnumerableSet.UintSet;

    uint256 constant RATE_PRECISION = 1e18;

    mapping(string => Campaign) campaigns;
    string[] campaignIds;
    mapping(string => mapping(address => UserInfo)) usersInfo;

    event Buy(
        address indexed user,
        string _campaignID,
        IERC20 srcToken,
        uint256 srcAmount,
        IERC20 dstToken,
        uint256 dstAmount
    );

    constructor() {}

    function setCampaign(
        string calldata _campaignID,
        bytes32 _merkleRoot,
        uint64 _startTime,
        uint64 _endTime,
        uint256 _srcCap,
        uint256 _dstCap,
        IERC20 _acceptToken,
        IERC20 _token
    ) external override onlyOwner {
        Campaign storage c = campaigns[_campaignID];
        c.merkleRoot = _merkleRoot;
        c.startTime = _startTime;
        c.endTime = _endTime;
        c.srcCap = _srcCap;
        c.rate = (_dstCap * RATE_PRECISION) / _srcCap;
        c.acceptToken = _acceptToken;
        c.token = _token;
        campaignIds.push(_campaignID);
    }

    function setCampaignToken(string calldata _campaignID, IERC20 _token)
        external
        override
        onlyOwner
    {
        Campaign storage c = campaigns[_campaignID];
        c.token = _token;
    }

    function buy(
        string calldata _campaignID,
        uint128 _index,
        uint256 _maxCap,
        uint256 _amount,
        bytes32[] calldata _merkleProof
    ) external payable override nonReentrant {
        address _user = tx.origin;
        Campaign storage c = campaigns[_campaignID];

        require(block.timestamp >= c.startTime, "not start");
        require(block.timestamp < c.endTime, "already end");

        // Verify the whitelist proof.
        bytes32 node = keccak256(
            abi.encodePacked(_campaignID, _index, _user, _maxCap)
        );
        require(
            MerkleProof.verify(_merkleProof, c.merkleRoot, node),
            "Invalid whitelist proof"
        );

        c.totalSource += _amount;
        require(c.totalSource <= c.srcCap, "exceed total cap");

        UserInfo storage userInfo = usersInfo[_campaignID][_user];
        userInfo.contribute += _amount;

        require(userInfo.contribute <= _maxCap, "exceed individual cap");

        uint256 tokenAmount = (_amount * c.rate) / RATE_PRECISION;
        userInfo.allocation += tokenAmount;
        c.totalDest += tokenAmount;

        // collect fund
        if (c.acceptToken == IERC20(address(0))) {
            require(msg.value == _amount, "amount not enough");
        } else {
            c.acceptToken.safeTransferFrom(_user, address(this), _amount);
        }

        emit Buy(
            _user,
            _campaignID,
            c.acceptToken,
            _amount,
            c.token,
            tokenAmount
        );
    }

    function getUserInfo(string calldata _campaignID, address _user)
        external
        view
        override
        returns (UserInfo memory)
    {
        return usersInfo[_campaignID][_user];
    }

    function getCampaign(string calldata _campaignID)
        external
        view
        override
        returns (Campaign memory)
    {
        return campaigns[_campaignID];
    }

    function getCampaignIds() external view override returns (string[] memory) {
        return campaignIds;
    }

    function withdrawSaleFund(string calldata _campaignID, address _to)
        external
        override
        onlyOwner
    {
        Campaign memory c = campaigns[_campaignID];
        require(!c.isFundWithdraw, "already withdraw");
        require(block.timestamp > c.endTime, "not end");
        c.isFundWithdraw = true;
        _safeTransfer(c.acceptToken, _to, c.totalSource);
    }

    function emergencyWithdraw(
        IERC20 _token,
        address _to,
        uint256 _amount
    ) external override onlyOwner {
        _safeTransfer(_token, _to, _amount);
    }

    function _safeTransfer(
        IERC20 _token,
        address _to,
        uint256 _amount
    ) internal {
        if (_token == IERC20(address(0))) {
            (bool success, ) = _to.call{value: _amount}("");
            require(success, "transfer failed");
        } else {
            _token.safeTransfer(_to, _amount);
        }
    }
}

// File: @openzeppelin/contracts/interfaces/IERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../token/ERC20/IERC20.sol";

// File: contracts/interfaces/ITokenSale.sol



// SPDX-License-Identifier: agpl-3.0
pragma solidity ^0.8.0;

import "@openzeppelin/contracts/interfaces/IERC20.sol";

interface ITokenSale {
    struct Campaign {
        bytes32 merkleRoot;
        uint64 startTime;
        uint64 endTime;
        uint256 srcCap;
        uint256 rate;
        uint256 totalSource;
        uint256 totalDest;
        bool isFundWithdraw;
        IERC20 token;
        IERC20 acceptToken;
    }

    struct UserInfo {
        uint256 allocation;
        uint256 contribute;
    }

    function setCampaign(
        string calldata _campaignID,
        bytes32 _merkleRoot,
        uint64 _startTime,
        uint64 _endTime,
        uint256 _srcCap,
        uint256 _dstCap,
        IERC20 _acceptToken,
        IERC20 _token
    ) external;

    function setCampaignToken(
        string calldata _campaignID,
        IERC20 _token
    ) external;

    function buy(
        string calldata _campaignID,
        uint128 _index,
        uint256 _maxCap,
        uint256 _amount,
        bytes32[] calldata _merkleProof
    ) external payable;

    function withdrawSaleFund(string calldata _campaignID, address _to)
        external;

    function emergencyWithdraw(
        IERC20 _token,
        address _to,
        uint256 _amount
    ) external;

    function getUserInfo(string calldata _campaignID, address _user)
        external
        view
        returns (UserInfo memory);

    function getCampaign(string calldata _campaignID)
        external
        view
        returns (Campaign memory);

    function getCampaignIds() external view returns (string[] memory);
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @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 `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, 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 `sender` to `recipient` 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 sender,
        address recipient,
        uint256 amount
    ) external returns (bool);

    /**
     * @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);
}

// File: @openzeppelin/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../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.
 *
 * By default, the owner account will be the one that deploys the contract. 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;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _setOwner(_msgSender());
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _setOwner(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 {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _setOwner(newOwner);
    }

    function _setOwner(address newOwner) private {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// File: @openzeppelin/contracts/utils/structs/EnumerableSet.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
 * and `uint256` (`UintSet`) are supported.
 */
library EnumerableSet {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Set type with
    // bytes32 values.
    // The Set implementation uses private functions, and user-facing
    // implementations (such as AddressSet) are just wrappers around the
    // underlying Set.
    // This means that we can only create new EnumerableSets for types that fit
    // in bytes32.

    struct Set {
        // Storage of set values
        bytes32[] _values;
        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping(bytes32 => uint256) _indexes;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function _add(Set storage set, bytes32 value) private returns (bool) {
        if (!_contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function _remove(Set storage set, bytes32 value) private returns (bool) {
        // We read and store the value's index to prevent multiple reads from the same storage slot
        uint256 valueIndex = set._indexes[value];

        if (valueIndex != 0) {
            // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.

            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;

            if (lastIndex != toDeleteIndex) {
                bytes32 lastvalue = set._values[lastIndex];

                // Move the last value to the index where the value to delete is
                set._values[toDeleteIndex] = lastvalue;
                // Update the index for the moved value
                set._indexes[lastvalue] = valueIndex; // Replace lastvalue's index to valueIndex
            }

            // Delete the slot where the moved value was stored
            set._values.pop();

            // Delete the index for the deleted slot
            delete set._indexes[value];

            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function _contains(Set storage set, bytes32 value) private view returns (bool) {
        return set._indexes[value] != 0;
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function _length(Set storage set) private view returns (uint256) {
        return set._values.length;
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function _at(Set storage set, uint256 index) private view returns (bytes32) {
        return set._values[index];
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function _values(Set storage set) private view returns (bytes32[] memory) {
        return set._values;
    }

    // Bytes32Set

    struct Bytes32Set {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _add(set._inner, value);
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _remove(set._inner, value);
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
        return _contains(set._inner, value);
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(Bytes32Set storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
        return _at(set._inner, index);
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(Bytes32Set storage set) internal view returns (bytes32[] memory) {
        return _values(set._inner);
    }

    // AddressSet

    struct AddressSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        return _add(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        return _remove(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return _contains(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(AddressSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        return address(uint160(uint256(_at(set._inner, index))));
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(AddressSet storage set) internal view returns (address[] memory) {
        bytes32[] memory store = _values(set._inner);
        address[] memory result;

        assembly {
            result := store
        }

        return result;
    }

    // UintSet

    struct UintSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(UintSet storage set, uint256 value) internal returns (bool) {
        return _add(set._inner, bytes32(value));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(UintSet storage set, uint256 value) internal returns (bool) {
        return _remove(set._inner, bytes32(value));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(UintSet storage set, uint256 value) internal view returns (bool) {
        return _contains(set._inner, bytes32(value));
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function length(UintSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(UintSet storage set, uint256 index) internal view returns (uint256) {
        return uint256(_at(set._inner, index));
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(UintSet storage set) internal view returns (uint256[] memory) {
        bytes32[] memory store = _values(set._inner);
        uint256[] memory result;

        assembly {
            result := store
        }

        return result;
    }
}

// File: @openzeppelin/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT

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;
    }
}

// File: @openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../IERC20.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;

    function safeTransfer(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    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));
    }

    function safeIncreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    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");
            uint256 newAllowance = oldAllowance - value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
    }

    /**
     * @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");
        if (returndata.length > 0) {
            // Return data is optional
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}

// File: @openzeppelin/contracts/security/ReentrancyGuard.sol



// SPDX-License-Identifier: MIT

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 make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;

        _;

        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}

// File: @openzeppelin/contracts/utils/cryptography/MerkleProof.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev These functions deal with verification of Merkle Trees proofs.
 *
 * The proofs can be generated using the JavaScript library
 * https://github.com/miguelmota/merkletreejs[merkletreejs].
 * Note: the hashing algorithm should be keccak256 and pair sorting should be enabled.
 *
 * See `test/utils/cryptography/MerkleProof.test.js` for some examples.
 */
library MerkleProof {
    /**
     * @dev Returns true if a `leaf` can be proved to be a part of a Merkle tree
     * defined by `root`. For this, a `proof` must be provided, containing
     * sibling hashes on the branch from the leaf to the root of the tree. Each
     * pair of leaves and each pair of pre-images are assumed to be sorted.
     */
    function verify(
        bytes32[] memory proof,
        bytes32 root,
        bytes32 leaf
    ) internal pure returns (bool) {
        bytes32 computedHash = leaf;

        for (uint256 i = 0; i < proof.length; i++) {
            bytes32 proofElement = proof[i];

            if (computedHash <= proofElement) {
                // Hash(current computed hash + current element of the proof)
                computedHash = keccak256(abi.encodePacked(computedHash, proofElement));
            } else {
                // Hash(current element of the proof + current computed hash)
                computedHash = keccak256(abi.encodePacked(proofElement, computedHash));
            }
        }

        // Check if the computed hash (root) is equal to the provided root
        return computedHash == root;
    }
}

// File: @openzeppelin/contracts/utils/Address.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @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
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        assembly {
            size := extcodesize(account)
        }
        return size > 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://diligence.consensys.net/posts/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/v0.5.11/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 functionCall(target, data, "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");
        require(isContract(target), "Address: call to non-contract");

        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResult(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) {
        require(isContract(target), "Address: static call to non-contract");

        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResult(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) {
        require(isContract(target), "Address: delegate call to non-contract");

        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason 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 {
            // 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

                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}