// File: /contracts/cryptofoxes/CryptoFoxesSlots.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "./interfaces/ICryptoFoxesOriginsV2.sol";
import "./interfaces/ICryptoFoxesStakingV2.sol";
import "./CryptoFoxesUtility.sol";

// @author: miinded.com
contract CryptoFoxesSlots is Ownable, CryptoFoxesUtility {
    ICryptoFoxesStakingV2 public cryptoFoxesStakingV2;
    ICryptoFoxesOriginsV2 public cryptoFoxesOrigin;
    uint256 constant basePrice = 10 ** 18;
    uint256[21] private slotPrice;

    constructor(address _cryptoFoxesOrigin, address _cryptoFoxesStakingV2) {
        cryptoFoxesOrigin = ICryptoFoxesOriginsV2(_cryptoFoxesOrigin);
        cryptoFoxesStakingV2 = ICryptoFoxesStakingV2(_cryptoFoxesStakingV2);

        slotPrice[10] = 600 * basePrice;
        slotPrice[11] = 760 * basePrice;
        slotPrice[12] = 970 * basePrice;
        slotPrice[13] = 1230 * basePrice;
        slotPrice[14] = 1560 * basePrice;
        slotPrice[15] = 1980 * basePrice;
        slotPrice[16] = 2520 * basePrice;
        slotPrice[17] = 3190 * basePrice;
        slotPrice[18] = 4060 * basePrice;
        slotPrice[19] = 5160 * basePrice;
        slotPrice[20] = 6550 * basePrice;
    }

    function unlockSlot(uint16 _tokenIdOrigin, uint8 _count) public {
        require(!disablePublicFunctions, "Function disabled");
        _unlockSlot(_msgSender(), _tokenIdOrigin, _count);
    }
    function unlockSlotByContract(address _wallet, uint16 _tokenIdOrigin, uint8 _count) public isFoxContract {
        _unlockSlot(_wallet, _tokenIdOrigin, _count);
    }

    function _unlockSlot(address _wallet, uint16 _tokenIdOrigin, uint8 _count) private {

        require(cryptoFoxesOrigin.ownerOf(_tokenIdOrigin) == _wallet, "CryptoFoxesSlots:unlockSlot Bad Owner");

        uint8 currentMaxSlot = cryptoFoxesStakingV2.getOriginMaxSlot(_tokenIdOrigin);
        if(currentMaxSlot == 0){
            currentMaxSlot = 9;
        }
        uint256 price = getTotalPrice(currentMaxSlot, _count);
        require(IERC20(address(cryptofoxesSteak)).balanceOf(_wallet) >= price, "CryptoFoxesSlots:unlockSlot balance to low");
        IERC20(address(cryptofoxesSteak)).transferFrom(_wallet, owner(), price);
        cryptoFoxesStakingV2.unlockSlot(_tokenIdOrigin, _count);
    }

    function getStepPrice(uint256 _step) public view returns(uint256){
        require(_step > 0 && _step <= 20, "CryptoFoxesSlots:unlockSlot Out of limit");

        return slotPrice[_step];
    }

    function getTotalPrice(uint8 _currentMaxSlot, uint256 _count) public view returns(uint256){
        uint256 price = 0;
        for(uint256 i = 0; i < _count; i++){
            price += slotPrice[_currentMaxSlot + i + 1];
        }
        return price;
    }
}
// File: /contracts/cryptofoxes/interfaces/ICryptoFoxesSteak.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

// @author: miinded.com

interface ICryptoFoxesSteak {
    function addRewards(address _to, uint256 _amount) external;
    function withdrawRewards(address _to) external;
    function isPaused() external view returns(bool);
    function dateEndRewards() external view returns(uint256);
}
// File: /contracts/cryptofoxes/interfaces/ICryptoFoxesStakingV2.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

// @author: miinded.com
import "./ICryptoFoxesStakingStruct.sol";

interface ICryptoFoxesStakingV2 is ICryptoFoxesStakingStruct  {
    function getFoxesV2(uint16 _tokenId) external view returns(Staking memory);
    function getOriginMaxSlot(uint16 _tokenIdOrigin) external view returns(uint8);
    function getStakingTokenV2(uint16 _tokenId) external view returns(uint256);
    function getV2ByOrigin(uint16 _tokenIdOrigin) external view returns(Staking[] memory);
    function getOriginByV2(uint16 _tokenId) external view returns(uint16);
    function unlockSlot(uint16 _tokenId, uint8 _count) external;
    function _currentTime(uint256 _currentTimestamp) external view returns(uint256);
}
// File: /contracts/cryptofoxes/interfaces/ICryptoFoxesStakingStruct.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

// @author: miinded.com

interface ICryptoFoxesStakingStruct {

    struct Staking {
        uint8 slotIndex;
        uint16 tokenId;
        uint16 origin;
        uint64 timestampV2;
        address owner;
    }

    struct Origin{
        uint8 maxSlots;
        uint16[] stacked;
    }

}
// File: /contracts/cryptofoxes/interfaces/ICryptoFoxesOriginsV2.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

// @author: miinded.com
import "./ICryptoFoxesOrigins.sol";
import "@openzeppelin/contracts/token/ERC721/IERC721.sol";

interface ICryptoFoxesOriginsV2 is ICryptoFoxesOrigins, IERC721  {
    function walletOfOwner(address _owner) external view returns(uint256[] memory);
}
// File: /contracts/cryptofoxes/interfaces/ICryptoFoxesOrigins.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

// @author: miinded.com

interface ICryptoFoxesOrigins {
    function getStackingToken(uint256 tokenId) external view returns(uint256);
    function _currentTime(uint256 _currentTimestamp) external view returns(uint256);
}
// File: /contracts/cryptofoxes/CryptoFoxesUtility.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "./interfaces/ICryptoFoxesSteak.sol";
import "./CryptoFoxesAllowed.sol";

// @author: miinded.com

abstract contract CryptoFoxesUtility is Ownable,CryptoFoxesAllowed, ICryptoFoxesSteak {
    using SafeMath for uint256;

    uint256 public endRewards = 0;
    ICryptoFoxesSteak public cryptofoxesSteak;
    bool public disablePublicFunctions = false;

    function setCryptoFoxesSteak(address _contract) public onlyOwner {
        cryptofoxesSteak = ICryptoFoxesSteak(_contract);
        setAllowedContract(_contract, true);
        synchroEndRewards();
    }
    function _addRewards(address _to, uint256 _amount) internal {
        cryptofoxesSteak.addRewards(_to, _amount);
    }
    function addRewards(address _to, uint256 _amount) public override isFoxContract  {
        _addRewards(_to, _amount);
    }
    function withdrawRewards(address _to) public override isFoxContract {
        cryptofoxesSteak.withdrawRewards(_to);
    }
    function _withdrawRewards(address _to) internal {
        cryptofoxesSteak.withdrawRewards(_to);
    }
    function isPaused() public view override returns(bool){
        return cryptofoxesSteak.isPaused();
    }
    function synchroEndRewards() public {
        endRewards = cryptofoxesSteak.dateEndRewards();
    }
    function dateEndRewards() public view override returns(uint256){
        require(endRewards > 0, "End Rewards error");
        return endRewards;
    }
    function _currentTime(uint256 _currentTimestamp) public view virtual returns (uint256) {
        return min(_currentTimestamp, dateEndRewards());
    }
    function min(uint256 a, uint256 b) public pure returns (uint256){
        return a > b ? b : a;
    }
    function max(uint256 a, uint256 b) public pure returns (uint256){
        return a > b ? a : b;
    }
    function setDisablePublicFunctions(bool _toggle) public isFoxContractOrOwner{
        disablePublicFunctions = _toggle;
    }
}
// File: /contracts/cryptofoxes/CryptoFoxesAllowed.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "./interfaces/ICryptoFoxesSteak.sol";

// @author: miinded.com

abstract contract CryptoFoxesAllowed is Ownable {

    mapping (address => bool) public allowedContracts;

    modifier isFoxContract() {
        require(allowedContracts[_msgSender()] == true, "Not allowed");
        _;
    }
    
    modifier isFoxContractOrOwner() {
        require(allowedContracts[_msgSender()] == true || _msgSender() == owner(), "Not allowed");
        _;
    }

    function setAllowedContract(address _contract, bool _allowed) public onlyOwner {
        allowedContracts[_contract] = _allowed;
    }

}
// File: @openzeppelin/contracts/utils/math/SafeMath.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (utils/math/SafeMath.sol)

pragma solidity ^0.8.0;

// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        return a + b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}

// File: @openzeppelin/contracts/utils/introspection/IERC165.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (utils/introspection/IERC165.sol)

pragma solidity ^0.8.0;

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

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (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;
    }
}

// File: @openzeppelin/contracts/token/ERC721/IERC721.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (token/ERC721/IERC721.sol)

pragma solidity ^0.8.0;

import "../../utils/introspection/IERC165.sol";

/**
 * @dev Required interface of an ERC721 compliant contract.
 */
interface IERC721 is IERC165 {
    /**
     * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
     */
    event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);

    /**
     * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
     */
    event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);

    /**
     * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
     */
    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

    /**
     * @dev Returns the number of tokens in ``owner``'s account.
     */
    function balanceOf(address owner) external view returns (uint256 balance);

    /**
     * @dev Returns the owner of the `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function ownerOf(uint256 tokenId) external view returns (address owner);

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
     * are aware of the ERC721 protocol to prevent tokens from being forever locked.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

    /**
     * @dev Transfers `tokenId` token from `from` to `to`.
     *
     * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

    /**
     * @dev Gives permission to `to` to transfer `tokenId` token to another account.
     * The approval is cleared when the token is transferred.
     *
     * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
     *
     * Requirements:
     *
     * - The caller must own the token or be an approved operator.
     * - `tokenId` must exist.
     *
     * Emits an {Approval} event.
     */
    function approve(address to, uint256 tokenId) external;

    /**
     * @dev Returns the account approved for `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function getApproved(uint256 tokenId) external view returns (address operator);

    /**
     * @dev Approve or remove `operator` as an operator for the caller.
     * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
     *
     * Requirements:
     *
     * - The `operator` cannot be the caller.
     *
     * Emits an {ApprovalForAll} event.
     */
    function setApprovalForAll(address operator, bool _approved) external;

    /**
     * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
     *
     * See {setApprovalForAll}
     */
    function isApprovedForAll(address owner, address operator) external view returns (bool);

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes calldata data
    ) external;
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (token/ERC20/IERC20.sol)

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
// OpenZeppelin Contracts v4.4.0 (access/Ownable.sol)

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() {
        _transferOwnership(_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 {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}