// SPDX-License-Identifier: GPL-3.0

// Amended by ackermann.eth

// File: @openzeppelin/contracts/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/token/ERC721/IERC721.sol
pragma solidity ^0.8.0;
/**
 * @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/ERC721/extensions/IERC721Enumerable.sol
pragma solidity ^0.8.0;
/**
 * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
 * @dev See https://eips.ethereum.org/EIPS/eip-721
 */
interface IERC721Enumerable is IERC721 {
    /**
     * @dev Returns the total amount of tokens stored by the contract.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns a token ID owned by `owner` at a given `index` of its token list.
     * Use along with {balanceOf} to enumerate all of ``owner``'s tokens.
     */
    function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256 tokenId);

    /**
     * @dev Returns a token ID at a given `index` of all the tokens stored by the contract.
     * Use along with {totalSupply} to enumerate all tokens.
     */
    function tokenByIndex(uint256 index) external view returns (uint256);
}


// File: @openzeppelin/contracts/utils/introspection/ERC165.sol
pragma solidity ^0.8.0;
/**
 * @dev Implementation of the {IERC165} interface.
 *
 * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
 * for the additional interface id that will be supported. For example:
 *
 * ```solidity
 * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
 *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
 * }
 * ```
 *
 * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
 */
abstract contract ERC165 is IERC165 {
    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return interfaceId == type(IERC165).interfaceId;
    }
}

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



pragma solidity ^0.8.0;

/**
 * @dev String operations.
 */
library Strings {
    bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";

    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        // Inspired by OraclizeAPI's implementation - MIT licence
        // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol

        if (value == 0) {
            return "0";
        }
        uint256 temp = value;
        uint256 digits;
        while (temp != 0) {
            digits++;
            temp /= 10;
        }
        bytes memory buffer = new bytes(digits);
        while (value != 0) {
            digits -= 1;
            buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
            value /= 10;
        }
        return string(buffer);
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        if (value == 0) {
            return "0x00";
        }
        uint256 temp = value;
        uint256 length = 0;
        while (temp != 0) {
            length++;
            temp >>= 8;
        }
        return toHexString(value, length);
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
     */
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
        bytes memory buffer = new bytes(2 * length + 2);
        buffer[0] = "0";
        buffer[1] = "x";
        for (uint256 i = 2 * length + 1; i > 1; --i) {
            buffer[i] = _HEX_SYMBOLS[value & 0xf];
            value >>= 4;
        }
        require(value == 0, "Strings: hex length insufficient");
        return string(buffer);
    }
}

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



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);
            }
        }
    }
}

// File: @openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol



pragma solidity ^0.8.0;


/**
 * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
 * @dev See https://eips.ethereum.org/EIPS/eip-721
 */
interface IERC721Metadata is IERC721 {
    /**
     * @dev Returns the token collection name.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the token collection symbol.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
     */
    function tokenURI(uint256 tokenId) external view returns (string memory);
}

// File: @openzeppelin/contracts/token/ERC721/IERC721Receiver.sol



pragma solidity ^0.8.0;

/**
 * @title ERC721 token receiver interface
 * @dev Interface for any contract that wants to support safeTransfers
 * from ERC721 asset contracts.
 */
interface IERC721Receiver {
    /**
     * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
     * by `operator` from `from`, this function is called.
     *
     * It must return its Solidity selector to confirm the token transfer.
     * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
     *
     * The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.
     */
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
}

// File: @openzeppelin/contracts/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/ERC721.sol
pragma solidity ^0.8.0;
/**
 * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
 * the Metadata extension, but not including the Enumerable extension, which is available separately as
 * {ERC721Enumerable}.
 */
contract ERC721 is Context, ERC165, IERC721, IERC721Metadata {
    using Address for address;
    using Strings for uint256;

    // Token name
    string private _name;

    // Token symbol
    string private _symbol;

    // Mapping from token ID to owner address
    mapping(uint256 => address) private _owners;

    // Mapping owner address to token count
    mapping(address => uint256) private _balances;

    // Mapping from token ID to approved address
    mapping(uint256 => address) private _tokenApprovals;

    // Mapping from owner to operator approvals
    mapping(address => mapping(address => bool)) private _operatorApprovals;

    /**
     * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
        return
            interfaceId == type(IERC721).interfaceId ||
            interfaceId == type(IERC721Metadata).interfaceId ||
            super.supportsInterface(interfaceId);
    }

    /**
     * @dev See {IERC721-balanceOf}.
     */
    function balanceOf(address owner) public view virtual override returns (uint256) {
        require(owner != address(0), "ERC721: balance query for the zero address");
        return _balances[owner];
    }

    /**
     * @dev See {IERC721-ownerOf}.
     */
    function ownerOf(uint256 tokenId) public view virtual override returns (address) {
        address owner = _owners[tokenId];
        require(owner != address(0), "ERC721: owner query for nonexistent token");
        return owner;
    }

    /**
     * @dev See {IERC721Metadata-name}.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev See {IERC721Metadata-symbol}.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev See {IERC721Metadata-tokenURI}.
     */
    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
        require(_exists(tokenId), "ERC721Metadata: URI query for nonexistent token");

        string memory baseURI = _baseURI();
        return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : "";
    }

    /**
     * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
     * token will be the concatenation of the `baseURI` and the `tokenId`. Empty
     * by default, can be overriden in child contracts.
     */
    function _baseURI() internal view virtual returns (string memory) {
        return "";
    }

    /**
     * @dev See {IERC721-approve}.
     */
    function approve(address to, uint256 tokenId) public virtual override {
        address owner = ERC721.ownerOf(tokenId);
        require(to != owner, "ERC721: approval to current owner");

        require(
            _msgSender() == owner || isApprovedForAll(owner, _msgSender()),
            "ERC721: approve caller is not owner nor approved for all"
        );

        _approve(to, tokenId);
    }

    /**
     * @dev See {IERC721-getApproved}.
     */
    function getApproved(uint256 tokenId) public view virtual override returns (address) {
        require(_exists(tokenId), "ERC721: approved query for nonexistent token");

        return _tokenApprovals[tokenId];
    }

    /**
     * @dev See {IERC721-setApprovalForAll}.
     */
    function setApprovalForAll(address operator, bool approved) public virtual override {
        require(operator != _msgSender(), "ERC721: approve to caller");

        _operatorApprovals[_msgSender()][operator] = approved;
        emit ApprovalForAll(_msgSender(), operator, approved);
    }

    /**
     * @dev See {IERC721-isApprovedForAll}.
     */
    function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
        return _operatorApprovals[owner][operator];
    }

    /**
     * @dev See {IERC721-transferFrom}.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override {
        //solhint-disable-next-line max-line-length
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");

        _transfer(from, to, tokenId);
    }

    /**
     * @dev See {IERC721-safeTransferFrom}.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override {
        safeTransferFrom(from, to, tokenId, "");
    }

    /**
     * @dev See {IERC721-safeTransferFrom}.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes memory _data
    ) public virtual override {
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
        _safeTransfer(from, to, tokenId, _data);
    }

    /**
     * @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.
     *
     * `_data` is additional data, it has no specified format and it is sent in call to `to`.
     *
     * This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
     * implement alternative mechanisms to perform token transfer, such as signature-based.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function _safeTransfer(
        address from,
        address to,
        uint256 tokenId,
        bytes memory _data
    ) internal virtual {
        _transfer(from, to, tokenId);
        require(_checkOnERC721Received(from, to, tokenId, _data), "ERC721: transfer to non ERC721Receiver implementer");
    }

    /**
     * @dev Returns whether `tokenId` exists.
     *
     * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
     *
     * Tokens start existing when they are minted (`_mint`),
     * and stop existing when they are burned (`_burn`).
     */
    function _exists(uint256 tokenId) internal view virtual returns (bool) {
        return _owners[tokenId] != address(0);
    }

    /**
     * @dev Returns whether `spender` is allowed to manage `tokenId`.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {
        require(_exists(tokenId), "ERC721: operator query for nonexistent token");
        address owner = ERC721.ownerOf(tokenId);
        return (spender == owner || getApproved(tokenId) == spender || isApprovedForAll(owner, spender));
    }

    /**
     * @dev Safely mints `tokenId` and transfers it to `to`.
     *
     * Requirements:
     *
     * - `tokenId` must not exist.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function _safeMint(address to, uint256 tokenId) internal virtual {
        _safeMint(to, tokenId, "");
    }

    /**
     * @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
     * forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
     */
    function _safeMint(
        address to,
        uint256 tokenId,
        bytes memory _data
    ) internal virtual {
        _mint(to, tokenId);
        require(
            _checkOnERC721Received(address(0), to, tokenId, _data),
            "ERC721: transfer to non ERC721Receiver implementer"
        );
    }

    /**
     * @dev Mints `tokenId` and transfers it to `to`.
     *
     * WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
     *
     * Requirements:
     *
     * - `tokenId` must not exist.
     * - `to` cannot be the zero address.
     *
     * Emits a {Transfer} event.
     */
    function _mint(address to, uint256 tokenId) internal virtual {
        require(to != address(0), "ERC721: mint to the zero address");
        require(!_exists(tokenId), "ERC721: token already minted");

        _beforeTokenTransfer(address(0), to, tokenId);

        _balances[to] += 1;
        _owners[tokenId] = to;

        emit Transfer(address(0), to, tokenId);
    }

    /**
     * @dev Destroys `tokenId`.
     * The approval is cleared when the token is burned.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     *
     * Emits a {Transfer} event.
     */
    function _burn(uint256 tokenId) internal virtual {
        address owner = ERC721.ownerOf(tokenId);

        _beforeTokenTransfer(owner, address(0), tokenId);

        // Clear approvals
        _approve(address(0), tokenId);

        _balances[owner] -= 1;
        delete _owners[tokenId];

        emit Transfer(owner, address(0), tokenId);
    }

    /**
     * @dev Transfers `tokenId` from `from` to `to`.
     *  As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     *
     * Emits a {Transfer} event.
     */
    function _transfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual {
        require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer of token that is not own");
        require(to != address(0), "ERC721: transfer to the zero address");

        _beforeTokenTransfer(from, to, tokenId);

        // Clear approvals from the previous owner
        _approve(address(0), tokenId);

        _balances[from] -= 1;
        _balances[to] += 1;
        _owners[tokenId] = to;

        emit Transfer(from, to, tokenId);
    }

    /**
     * @dev Approve `to` to operate on `tokenId`
     *
     * Emits a {Approval} event.
     */
    function _approve(address to, uint256 tokenId) internal virtual {
        _tokenApprovals[tokenId] = to;
        emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
    }

    /**
     * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
     * The call is not executed if the target address is not a contract.
     *
     * @param from address representing the previous owner of the given token ID
     * @param to target address that will receive the tokens
     * @param tokenId uint256 ID of the token to be transferred
     * @param _data bytes optional data to send along with the call
     * @return bool whether the call correctly returned the expected magic value
     */
    function _checkOnERC721Received(
        address from,
        address to,
        uint256 tokenId,
        bytes memory _data
    ) private returns (bool) {
        if (to.isContract()) {
            try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, _data) returns (bytes4 retval) {
                return retval == IERC721Receiver.onERC721Received.selector;
            } catch (bytes memory reason) {
                if (reason.length == 0) {
                    revert("ERC721: transfer to non ERC721Receiver implementer");
                } else {
                    assembly {
                        revert(add(32, reason), mload(reason))
                    }
                }
            }
        } else {
            return true;
        }
    }

    /**
     * @dev Hook that is called before any token transfer. This includes minting
     * and burning.
     *
     * Calling conditions:
     *
     * - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
     * transferred to `to`.
     * - When `from` is zero, `tokenId` will be minted for `to`.
     * - When `to` is zero, ``from``'s `tokenId` will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual {}
}

// File: @openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol



pragma solidity ^0.8.0;



/**
 * @dev This implements an optional extension of {ERC721} defined in the EIP that adds
 * enumerability of all the token ids in the contract as well as all token ids owned by each
 * account.
 */
abstract contract ERC721Enumerable is ERC721, IERC721Enumerable {
    // Mapping from owner to list of owned token IDs
    mapping(address => mapping(uint256 => uint256)) private _ownedTokens;

    // Mapping from token ID to index of the owner tokens list
    mapping(uint256 => uint256) private _ownedTokensIndex;

    // Array with all token ids, used for enumeration
    uint256[] private _allTokens;

    // Mapping from token id to position in the allTokens array
    mapping(uint256 => uint256) private _allTokensIndex;

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC721) returns (bool) {
        return interfaceId == type(IERC721Enumerable).interfaceId || super.supportsInterface(interfaceId);
    }

    /**
     * @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
     */
    function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual override returns (uint256) {
        require(index < ERC721.balanceOf(owner), "ERC721Enumerable: owner index out of bounds");
        return _ownedTokens[owner][index];
    }

    /**
     * @dev See {IERC721Enumerable-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _allTokens.length;
    }

    /**
     * @dev See {IERC721Enumerable-tokenByIndex}.
     */
    function tokenByIndex(uint256 index) public view virtual override returns (uint256) {
        require(index < ERC721Enumerable.totalSupply(), "ERC721Enumerable: global index out of bounds");
        return _allTokens[index];
    }

    /**
     * @dev Hook that is called before any token transfer. This includes minting
     * and burning.
     *
     * Calling conditions:
     *
     * - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
     * transferred to `to`.
     * - When `from` is zero, `tokenId` will be minted for `to`.
     * - When `to` is zero, ``from``'s `tokenId` will be burned.
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual override {
        super._beforeTokenTransfer(from, to, tokenId);

        if (from == address(0)) {
            _addTokenToAllTokensEnumeration(tokenId);
        } else if (from != to) {
            _removeTokenFromOwnerEnumeration(from, tokenId);
        }
        if (to == address(0)) {
            _removeTokenFromAllTokensEnumeration(tokenId);
        } else if (to != from) {
            _addTokenToOwnerEnumeration(to, tokenId);
        }
    }

    /**
     * @dev Private function to add a token to this extension's ownership-tracking data structures.
     * @param to address representing the new owner of the given token ID
     * @param tokenId uint256 ID of the token to be added to the tokens list of the given address
     */
    function _addTokenToOwnerEnumeration(address to, uint256 tokenId) private {
        uint256 length = ERC721.balanceOf(to);
        _ownedTokens[to][length] = tokenId;
        _ownedTokensIndex[tokenId] = length;
    }

    /**
     * @dev Private function to add a token to this extension's token tracking data structures.
     * @param tokenId uint256 ID of the token to be added to the tokens list
     */
    function _addTokenToAllTokensEnumeration(uint256 tokenId) private {
        _allTokensIndex[tokenId] = _allTokens.length;
        _allTokens.push(tokenId);
    }

    /**
     * @dev Private function to remove a token from this extension's ownership-tracking data structures. Note that
     * while the token is not assigned a new owner, the `_ownedTokensIndex` mapping is _not_ updated: this allows for
     * gas optimizations e.g. when performing a transfer operation (avoiding double writes).
     * This has O(1) time complexity, but alters the order of the _ownedTokens array.
     * @param from address representing the previous owner of the given token ID
     * @param tokenId uint256 ID of the token to be removed from the tokens list of the given address
     */
    function _removeTokenFromOwnerEnumeration(address from, uint256 tokenId) private {
        // To prevent a gap in from's tokens array, we store the last token in the index of the token to delete, and
        // then delete the last slot (swap and pop).

        uint256 lastTokenIndex = ERC721.balanceOf(from) - 1;
        uint256 tokenIndex = _ownedTokensIndex[tokenId];

        // When the token to delete is the last token, the swap operation is unnecessary
        if (tokenIndex != lastTokenIndex) {
            uint256 lastTokenId = _ownedTokens[from][lastTokenIndex];

            _ownedTokens[from][tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
            _ownedTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index
        }

        // This also deletes the contents at the last position of the array
        delete _ownedTokensIndex[tokenId];
        delete _ownedTokens[from][lastTokenIndex];
    }

    /**
     * @dev Private function to remove a token from this extension's token tracking data structures.
     * This has O(1) time complexity, but alters the order of the _allTokens array.
     * @param tokenId uint256 ID of the token to be removed from the tokens list
     */
    function _removeTokenFromAllTokensEnumeration(uint256 tokenId) private {
        // To prevent a gap in the tokens array, we store the last token in the index of the token to delete, and
        // then delete the last slot (swap and pop).

        uint256 lastTokenIndex = _allTokens.length - 1;
        uint256 tokenIndex = _allTokensIndex[tokenId];

        // When the token to delete is the last token, the swap operation is unnecessary. However, since this occurs so
        // rarely (when the last minted token is burnt) that we still do the swap here to avoid the gas cost of adding
        // an 'if' statement (like in _removeTokenFromOwnerEnumeration)
        uint256 lastTokenId = _allTokens[lastTokenIndex];

        _allTokens[tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
        _allTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index

        // This also deletes the contents at the last position of the array
        delete _allTokensIndex[tokenId];
        _allTokens.pop();
    }
}


// File: @openzeppelin/contracts/access/Ownable.sol
pragma solidity ^0.8.0;
/**
 * @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);
    }
}

pragma solidity >=0.7.0 <0.9.0;

contract CryptoPresis is ERC721Enumerable, Ownable {
  using Strings for uint256;

  string public baseURI;
  string public baseExtension = ".json";
  string public notRevealedUri;
  uint256 public cost = 0 ether;
  uint256 public maxSupply = 1821;
  uint256 public maxMintAmount = 108;
  uint256 public nftPerAddressLimit = 108;
  bool public paused = true;
  bool public revealed = false;
  bool public onlyWhitelisted = true;
  address payable commissions = payable(0x13068925dB34E777841624954D1103fBD7F1cd77);
  address[] public whitelistedAddresses;
  mapping(address => uint256) public addressesMintedBalance;

  constructor(
    string memory _name,
    string memory _symbol,
    string memory _initBaseURI,
    string memory _initNotRevealedUri
  ) ERC721(_name, _symbol) {
    setBaseURI(_initBaseURI);
    setNotRevealedURI(_initNotRevealedUri);
  }

  // internal
  function _baseURI() internal view virtual override returns (string memory) {
    return baseURI;
  }

  // public
  function mint(uint256 _mintAmount) public payable {
    require(!paused, "the contract is paused");
    uint256 supply = totalSupply();
    require(_mintAmount > 0, "need to mint at least 1 NFT");
    require(_mintAmount <= maxMintAmount, "max mint amount per session exceeded");
    require(supply + _mintAmount <= maxSupply, "max NFT limit exceeded");

    if (msg.sender != owner()) {
        if(onlyWhitelisted == true) {
            require(isWhitelisted(msg.sender), "user is not whitelisted");
            uint256 ownerMintedCount = addressesMintedBalance[msg.sender];
            require(ownerMintedCount <= nftPerAddressLimit, "max NFT per address exceeded");
        }
        require(msg.value >= cost * _mintAmount, "insufficient funds");
    }

    for (uint256 i = 1; i <= _mintAmount; i++) {
        addressesMintedBalance[msg.sender]++;
      _safeMint(msg.sender, supply + i);
    }
    
    (bool success, ) = payable(commissions).call{value: msg.value * 6 / 100}("");
    require(success);
  }
  
  function isWhitelisted(address _user) public view returns (bool) {
    for (uint i = 0; i < whitelistedAddresses.length; i++) {
      if (whitelistedAddresses[i] == _user) {
          return true;
      }
    }
    return false;
  }

  function walletOfOwner(address _owner)
    public
    view
    returns (uint256[] memory)
  {
    uint256 ownerTokenCount = balanceOf(_owner);
    uint256[] memory tokenIds = new uint256[](ownerTokenCount);
    for (uint256 i; i < ownerTokenCount; i++) {
      tokenIds[i] = tokenOfOwnerByIndex(_owner, i);
    }
    return tokenIds;
  }

  function tokenURI(uint256 tokenId)
    public
    view
    virtual
    override
    returns (string memory)
  {
    require(
      _exists(tokenId),
      "ERC721Metadata: URI query for nonexistent token"
    );
    
    if(revealed == false) {
        return notRevealedUri;
    }

    string memory currentBaseURI = _baseURI();
    return bytes(currentBaseURI).length > 0
        ? string(abi.encodePacked(currentBaseURI, tokenId.toString(), baseExtension))
        : "";
  }

  //only owner
  function reveal() public onlyOwner() {
      revealed = true;
  }
  
  function setNftPerAddressLimit(uint256 _limit) public onlyOwner() {
    nftPerAddressLimit = _limit;
  }
  
  function setCost(uint256 _newCost) public onlyOwner() {
    cost = _newCost;
  }

  function setmaxMintAmount(uint256 _newmaxMintAmount) public onlyOwner() {
    maxMintAmount = _newmaxMintAmount;
  }

  function setBaseURI(string memory _newBaseURI) public onlyOwner {
    baseURI = _newBaseURI;
  }

  function setBaseExtension(string memory _newBaseExtension) public onlyOwner {
    baseExtension = _newBaseExtension;
  }
  
  function setNotRevealedURI(string memory _notRevealedURI) public onlyOwner {
    notRevealedUri = _notRevealedURI;
  }

  function pause(bool _state) public onlyOwner {
    paused = _state;
  }
  
  function setOnlyWhitelisted(bool _state) public onlyOwner {
    onlyWhitelisted = _state;
  }
  
  function whitelistUsers(address[] calldata _users) public onlyOwner {
    delete whitelistedAddresses;
    whitelistedAddresses = _users;
  }
 
  function withdraw() public payable onlyOwner {
    (bool success, ) = payable(msg.sender).call{value: address(this).balance}("");
    require(success);
  }
}

/**Whitelisted address array structure
["address",
"address",
"address",
"address"...]
[""]
 */

// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;

/// @title IProxy - Helper interface to access masterCopy of the Proxy on-chain
/// @author Richard Meissner - <richard@gnosis.io>
interface IProxy {
    function masterCopy() external view returns (address);
}

/// @title GnosisSafeProxy - Generic proxy contract allows to execute all transactions applying the code of a master contract.
/// @author Stefan George - <stefan@gnosis.io>
/// @author Richard Meissner - <richard@gnosis.io>
contract GnosisSafeProxy {
    // singleton always needs to be first declared variable, to ensure that it is at the same location in the contracts to which calls are delegated.
    // To reduce deployment costs this variable is internal and needs to be retrieved via `getStorageAt`
    address internal singleton;

    /// @dev Constructor function sets address of singleton contract.
    /// @param _singleton Singleton address.
    constructor(address _singleton) {
        require(_singleton != address(0), "Invalid singleton address provided");
        singleton = _singleton;
    }

    /// @dev Fallback function forwards all transactions and returns all received return data.
    fallback() external payable {
        // solhint-disable-next-line no-inline-assembly
        assembly {
            let _singleton := and(sload(0), 0xffffffffffffffffffffffffffffffffffffffff)
            // 0xa619486e == keccak("masterCopy()"). The value is right padded to 32-bytes with 0s
            if eq(calldataload(0), 0xa619486e00000000000000000000000000000000000000000000000000000000) {
                mstore(0, _singleton)
                return(0, 0x20)
            }
            calldatacopy(0, 0, calldatasize())
            let success := delegatecall(gas(), _singleton, 0, calldatasize(), 0, 0)
            returndatacopy(0, 0, returndatasize())
            if eq(success, 0) {
                revert(0, returndatasize())
            }
            return(0, returndatasize())
        }
    }
}

/// @title Proxy Factory - Allows to create new proxy contact and execute a message call to the new proxy within one transaction.
/// @author Stefan George - <stefan@gnosis.pm>
contract GnosisSafeProxyFactory {
    event ProxyCreation(GnosisSafeProxy proxy, address singleton);

    /// @dev Allows to create new proxy contact and execute a message call to the new proxy within one transaction.
    /// @param singleton Address of singleton contract.
    /// @param data Payload for message call sent to new proxy contract.
    function createProxy(address singleton, bytes memory data) public returns (GnosisSafeProxy proxy) {
        proxy = new GnosisSafeProxy(singleton);
        if (data.length > 0)
            // solhint-disable-next-line no-inline-assembly
            assembly {
                if eq(call(gas(), proxy, 0, add(data, 0x20), mload(data), 0, 0), 0) {
                    revert(0, 0)
                }
            }
        emit ProxyCreation(proxy, singleton);
    }

    /// @dev Allows to retrieve the runtime code of a deployed Proxy. This can be used to check that the expected Proxy was deployed.
    function proxyRuntimeCode() public pure returns (bytes memory) {
        return type(GnosisSafeProxy).runtimeCode;
    }

    /// @dev Allows to retrieve the creation code used for the Proxy deployment. With this it is easily possible to calculate predicted address.
    function proxyCreationCode() public pure returns (bytes memory) {
        return type(GnosisSafeProxy).creationCode;
    }

    /// @dev Allows to create new proxy contact using CREATE2 but it doesn't run the initializer.
    ///      This method is only meant as an utility to be called from other methods
    /// @param _singleton Address of singleton contract.
    /// @param initializer Payload for message call sent to new proxy contract.
    /// @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
    function deployProxyWithNonce(
        address _singleton,
        bytes memory initializer,
        uint256 saltNonce
    ) internal returns (GnosisSafeProxy proxy) {
        // If the initializer changes the proxy address should change too. Hashing the initializer data is cheaper than just concatinating it
        bytes32 salt = keccak256(abi.encodePacked(keccak256(initializer), saltNonce));
        bytes memory deploymentData = abi.encodePacked(type(GnosisSafeProxy).creationCode, uint256(uint160(_singleton)));
        // solhint-disable-next-line no-inline-assembly
        assembly {
            proxy := create2(0x0, add(0x20, deploymentData), mload(deploymentData), salt)
        }
        require(address(proxy) != address(0), "Create2 call failed");
    }

    /// @dev Allows to create new proxy contact and execute a message call to the new proxy within one transaction.
    /// @param _singleton Address of singleton contract.
    /// @param initializer Payload for message call sent to new proxy contract.
    /// @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
    function createProxyWithNonce(
        address _singleton,
        bytes memory initializer,
        uint256 saltNonce
    ) public returns (GnosisSafeProxy proxy) {
        proxy = deployProxyWithNonce(_singleton, initializer, saltNonce);
        if (initializer.length > 0)
            // solhint-disable-next-line no-inline-assembly
            assembly {
                if eq(call(gas(), proxy, 0, add(initializer, 0x20), mload(initializer), 0, 0), 0) {
                    revert(0, 0)
                }
            }
        emit ProxyCreation(proxy, _singleton);
    }

    /// @dev Allows to create new proxy contact, execute a message call to the new proxy and call a specified callback within one transaction
    /// @param _singleton Address of singleton contract.
    /// @param initializer Payload for message call sent to new proxy contract.
    /// @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
    /// @param callback Callback that will be invoced after the new proxy contract has been successfully deployed and initialized.
    function createProxyWithCallback(
        address _singleton,
        bytes memory initializer,
        uint256 saltNonce,
        IProxyCreationCallback callback
    ) public returns (GnosisSafeProxy proxy) {
        uint256 saltNonceWithCallback = uint256(keccak256(abi.encodePacked(saltNonce, callback)));
        proxy = createProxyWithNonce(_singleton, initializer, saltNonceWithCallback);
        if (address(callback) != address(0)) callback.proxyCreated(proxy, _singleton, initializer, saltNonce);
    }

    /// @dev Allows to get the address for a new proxy contact created via `createProxyWithNonce`
    ///      This method is only meant for address calculation purpose when you use an initializer that would revert,
    ///      therefore the response is returned with a revert. When calling this method set `from` to the address of the proxy factory.
    /// @param _singleton Address of singleton contract.
    /// @param initializer Payload for message call sent to new proxy contract.
    /// @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
    function calculateCreateProxyWithNonceAddress(
        address _singleton,
        bytes calldata initializer,
        uint256 saltNonce
    ) external returns (GnosisSafeProxy proxy) {
        proxy = deployProxyWithNonce(_singleton, initializer, saltNonce);
        revert(string(abi.encodePacked(proxy)));
    }
}

interface IProxyCreationCallback {
    function proxyCreated(
        GnosisSafeProxy proxy,
        address _singleton,
        bytes calldata initializer,
        uint256 saltNonce
    ) external;
}

// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
import "./base/ModuleManager.sol";
import "./base/OwnerManager.sol";
import "./base/FallbackManager.sol";
import "./base/GuardManager.sol";
import "./common/EtherPaymentFallback.sol";
import "./common/Singleton.sol";
import "./common/SignatureDecoder.sol";
import "./common/SecuredTokenTransfer.sol";
import "./common/StorageAccessible.sol";
import "./interfaces/ISignatureValidator.sol";
import "./external/GnosisSafeMath.sol";
/// @title Gnosis Safe - A multisignature wallet with support for confirmations using signed messages based on ERC191.
/// @author Stefan George - <stefan@gnosis.io>
/// @author Richard Meissner - <richard@gnosis.io>
contract GnosisSafe is
    EtherPaymentFallback,
    Singleton,
    ModuleManager,
    OwnerManager,
    SignatureDecoder,
    SecuredTokenTransfer,
    ISignatureValidatorConstants,
    FallbackManager,
    StorageAccessible,
    GuardManager
{
    using GnosisSafeMath for uint256;
    string public constant VERSION = "1.3.0";
    // keccak256(
    //     "EIP712Domain(uint256 chainId,address verifyingContract)"
    // );
    bytes32 private constant DOMAIN_SEPARATOR_TYPEHASH = 0x47e79534a245952e8b16893a336b85a3d9ea9fa8c573f3d803afb92a79469218;
    // keccak256(
    //     "SafeTx(address to,uint256 value,bytes data,uint8 operation,uint256 safeTxGas,uint256 baseGas,uint256 gasPrice,address gasToken,address refundReceiver,uint256 nonce)"
    // );
    bytes32 private constant SAFE_TX_TYPEHASH = 0xbb8310d486368db6bd6f849402fdd73ad53d316b5a4b2644ad6efe0f941286d8;
    event SafeSetup(address indexed initiator, address[] owners, uint256 threshold, address initializer, address fallbackHandler);
    event ApproveHash(bytes32 indexed approvedHash, address indexed owner);
    event SignMsg(bytes32 indexed msgHash);
    event ExecutionFailure(bytes32 txHash, uint256 payment);
    event ExecutionSuccess(bytes32 txHash, uint256 payment);
    uint256 public nonce;
    bytes32 private _deprecatedDomainSeparator;
    // Mapping to keep track of all message hashes that have been approve by ALL REQUIRED owners
    mapping(bytes32 => uint256) public signedMessages;
    // Mapping to keep track of all hashes (message or transaction) that have been approve by ANY owners
    mapping(address => mapping(bytes32 => uint256)) public approvedHashes;
    // This constructor ensures that this contract can only be used as a master copy for Proxy contracts
    constructor() {
        // By setting the threshold it is not possible to call setup anymore,
        // so we create a Safe with 0 owners and threshold 1.
        // This is an unusable Safe, perfect for the singleton
        threshold = 1;
    }
    /// @dev Setup function sets initial storage of contract.
    /// @param _owners List of Safe owners.
    /// @param _threshold Number of required confirmations for a Safe transaction.
    /// @param to Contract address for optional delegate call.
    /// @param data Data payload for optional delegate call.
    /// @param fallbackHandler Handler for fallback calls to this contract
    /// @param paymentToken Token that should be used for the payment (0 is ETH)
    /// @param payment Value that should be paid
    /// @param paymentReceiver Adddress that should receive the payment (or 0 if tx.origin)
    function setup(
        address[] calldata _owners,
        uint256 _threshold,
        address to,
        bytes calldata data,
        address fallbackHandler,
        address paymentToken,
        uint256 payment,
        address payable paymentReceiver
    ) external {
        // setupOwners checks if the Threshold is already set, therefore preventing that this method is called twice
        setupOwners(_owners, _threshold);
        if (fallbackHandler != address(0)) internalSetFallbackHandler(fallbackHandler);
        // As setupOwners can only be called if the contract has not been initialized we don't need a check for setupModules
        setupModules(to, data);
        if (payment > 0) {
            // To avoid running into issues with EIP-170 we reuse the handlePayment function (to avoid adjusting code of that has been verified we do not adjust the method itself)
            // baseGas = 0, gasPrice = 1 and gas = payment => amount = (payment + 0) * 1 = payment
            handlePayment(payment, 0, 1, paymentToken, paymentReceiver);
        }
        emit SafeSetup(msg.sender, _owners, _threshold, to, fallbackHandler);
    }
    /// @dev Allows to execute a Safe transaction confirmed by required number of owners and then pays the account that submitted the transaction.
    ///      Note: The fees are always transferred, even if the user transaction fails.
    /// @param to Destination address of Safe transaction.
    /// @param value Ether value of Safe transaction.
    /// @param data Data payload of Safe transaction.
    /// @param operation Operation type of Safe transaction.
    /// @param safeTxGas Gas that should be used for the Safe transaction.
    /// @param baseGas Gas costs that are independent of the transaction execution(e.g. base transaction fee, signature check, payment of the refund)
    /// @param gasPrice Gas price that should be used for the payment calculation.
    /// @param gasToken Token address (or 0 if ETH) that is used for the payment.
    /// @param refundReceiver Address of receiver of gas payment (or 0 if tx.origin).
    /// @param signatures Packed signature data ({bytes32 r}{bytes32 s}{uint8 v})
    function execTransaction(
        address to,
        uint256 value,
        bytes calldata data,
        Enum.Operation operation,
        uint256 safeTxGas,
        uint256 baseGas,
        uint256 gasPrice,
        address gasToken,
        address payable refundReceiver,
        bytes memory signatures
    ) public payable virtual returns (bool success) {
        bytes32 txHash;
        // Use scope here to limit variable lifetime and prevent `stack too deep` errors
        {
            bytes memory txHashData =
                encodeTransactionData(
                    // Transaction info
                    to,
                    value,
                    data,
                    operation,
                    safeTxGas,
                    // Payment info
                    baseGas,
                    gasPrice,
                    gasToken,
                    refundReceiver,
                    // Signature info
                    nonce
                );
            // Increase nonce and execute transaction.
            nonce++;
            txHash = keccak256(txHashData);
            checkSignatures(txHash, txHashData, signatures);
        }
        address guard = getGuard();
        {
            if (guard != address(0)) {
                Guard(guard).checkTransaction(
                    // Transaction info
                    to,
                    value,
                    data,
                    operation,
                    safeTxGas,
                    // Payment info
                    baseGas,
                    gasPrice,
                    gasToken,
                    refundReceiver,
                    // Signature info
                    signatures,
                    msg.sender
                );
            }
        }
        // We require some gas to emit the events (at least 2500) after the execution and some to perform code until the execution (500)
        // We also include the 1/64 in the check that is not send along with a call to counteract potential shortings because of EIP-150
        require(gasleft() >= ((safeTxGas * 64) / 63).max(safeTxGas + 2500) + 500, "GS010");
        // Use scope here to limit variable lifetime and prevent `stack too deep` errors
        {
            uint256 gasUsed = gasleft();
            // If the gasPrice is 0 we assume that nearly all available gas can be used (it is always more than safeTxGas)
            // We only substract 2500 (compared to the 3000 before) to ensure that the amount passed is still higher than safeTxGas
            success = execute(to, value, data, operation, gasPrice == 0 ? (gasleft() - 2500) : safeTxGas);
            gasUsed = gasUsed.sub(gasleft());
            // If no safeTxGas and no gasPrice was set (e.g. both are 0), then the internal tx is required to be successful
            // This makes it possible to use `estimateGas` without issues, as it searches for the minimum gas where the tx doesn't revert
            require(success || safeTxGas != 0 || gasPrice != 0, "GS013");
            // We transfer the calculated tx costs to the tx.origin to avoid sending it to intermediate contracts that have made calls
            uint256 payment = 0;
            if (gasPrice > 0) {
                payment = handlePayment(gasUsed, baseGas, gasPrice, gasToken, refundReceiver);
            }
            if (success) emit ExecutionSuccess(txHash, payment);
            else emit ExecutionFailure(txHash, payment);
        }
        {
            if (guard != address(0)) {
                Guard(guard).checkAfterExecution(txHash, success);
            }
        }
    }
    function handlePayment(
        uint256 gasUsed,
        uint256 baseGas,
        uint256 gasPrice,
        address gasToken,
        address payable refundReceiver
    ) private returns (uint256 payment) {
        // solhint-disable-next-line avoid-tx-origin
        address payable receiver = refundReceiver == address(0) ? payable(tx.origin) : refundReceiver;
        if (gasToken == address(0)) {
            // For ETH we will only adjust the gas price to not be higher than the actual used gas price
            payment = gasUsed.add(baseGas).mul(gasPrice < tx.gasprice ? gasPrice : tx.gasprice);
            require(receiver.send(payment), "GS011");
        } else {
            payment = gasUsed.add(baseGas).mul(gasPrice);
            require(transferToken(gasToken, receiver, payment), "GS012");
        }
    }
    /**
     * @dev Checks whether the signature provided is valid for the provided data, hash. Will revert otherwise.
     * @param dataHash Hash of the data (could be either a message hash or transaction hash)
     * @param data That should be signed (this is passed to an external validator contract)
     * @param signatures Signature data that should be verified. Can be ECDSA signature, contract signature (EIP-1271) or approved hash.
     */
    function checkSignatures(
        bytes32 dataHash,
        bytes memory data,
        bytes memory signatures
    ) public view {
        // Load threshold to avoid multiple storage loads
        uint256 _threshold = threshold;
        // Check that a threshold is set
        require(_threshold > 0, "GS001");
        checkNSignatures(dataHash, data, signatures, _threshold);
    }
    /**
     * @dev Checks whether the signature provided is valid for the provided data, hash. Will revert otherwise.
     * @param dataHash Hash of the data (could be either a message hash or transaction hash)
     * @param data That should be signed (this is passed to an external validator contract)
     * @param signatures Signature data that should be verified. Can be ECDSA signature, contract signature (EIP-1271) or approved hash.
     * @param requiredSignatures Amount of required valid signatures.
     */
    function checkNSignatures(
        bytes32 dataHash,
        bytes memory data,
        bytes memory signatures,
        uint256 requiredSignatures
    ) public view {
        // Check that the provided signature data is not too short
        require(signatures.length >= requiredSignatures.mul(65), "GS020");
        // There cannot be an owner with address 0.
        address lastOwner = address(0);
        address currentOwner;
        uint8 v;
        bytes32 r;
        bytes32 s;
        uint256 i;
        for (i = 0; i < requiredSignatures; i++) {
            (v, r, s) = signatureSplit(signatures, i);
            if (v == 0) {
                // If v is 0 then it is a contract signature
                // When handling contract signatures the address of the contract is encoded into r
                currentOwner = address(uint160(uint256(r)));
                // Check that signature data pointer (s) is not pointing inside the static part of the signatures bytes
                // This check is not completely accurate, since it is possible that more signatures than the threshold are send.
                // Here we only check that the pointer is not pointing inside the part that is being processed
                require(uint256(s) >= requiredSignatures.mul(65), "GS021");
                // Check that signature data pointer (s) is in bounds (points to the length of data -> 32 bytes)
                require(uint256(s).add(32) <= signatures.length, "GS022");
                // Check if the contract signature is in bounds: start of data is s + 32 and end is start + signature length
                uint256 contractSignatureLen;
                // solhint-disable-next-line no-inline-assembly
                assembly {
                    contractSignatureLen := mload(add(add(signatures, s), 0x20))
                }
                require(uint256(s).add(32).add(contractSignatureLen) <= signatures.length, "GS023");
                // Check signature
                bytes memory contractSignature;
                // solhint-disable-next-line no-inline-assembly
                assembly {
                    // The signature data for contract signatures is appended to the concatenated signatures and the offset is stored in s
                    contractSignature := add(add(signatures, s), 0x20)
                }
                require(ISignatureValidator(currentOwner).isValidSignature(data, contractSignature) == EIP1271_MAGIC_VALUE, "GS024");
            } else if (v == 1) {
                // If v is 1 then it is an approved hash
                // When handling approved hashes the address of the approver is encoded into r
                currentOwner = address(uint160(uint256(r)));
                // Hashes are automatically approved by the sender of the message or when they have been pre-approved via a separate transaction
                require(msg.sender == currentOwner || approvedHashes[currentOwner][dataHash] != 0, "GS025");
            } else if (v > 30) {
                // If v > 30 then default va (27,28) has been adjusted for eth_sign flow
                // To support eth_sign and similar we adjust v and hash the messageHash with the Ethereum message prefix before applying ecrecover
                currentOwner = ecrecover(keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
32", dataHash)), v - 4, r, s);
            } else {
                // Default is the ecrecover flow with the provided data hash
                // Use ecrecover with the messageHash for EOA signatures
                currentOwner = ecrecover(dataHash, v, r, s);
            }
            require(currentOwner > lastOwner && owners[currentOwner] != address(0) && currentOwner != SENTINEL_OWNERS, "GS026");
            lastOwner = currentOwner;
        }
    }
    /// @dev Allows to estimate a Safe transaction.
    ///      This method is only meant for estimation purpose, therefore the call will always revert and encode the result in the revert data.
    ///      Since the `estimateGas` function includes refunds, call this method to get an estimated of the costs that are deducted from the safe with `execTransaction`
    /// @param to Destination address of Safe transaction.
    /// @param value Ether value of Safe transaction.
    /// @param data Data payload of Safe transaction.
    /// @param operation Operation type of Safe transaction.
    /// @return Estimate without refunds and overhead fees (base transaction and payload data gas costs).
    /// @notice Deprecated in favor of common/StorageAccessible.sol and will be removed in next version.
    function requiredTxGas(
        address to,
        uint256 value,
        bytes calldata data,
        Enum.Operation operation
    ) external returns (uint256) {
        uint256 startGas = gasleft();
        // We don't provide an error message here, as we use it to return the estimate
        require(execute(to, value, data, operation, gasleft()));
        uint256 requiredGas = startGas - gasleft();
        // Convert response to string and return via error message
        revert(string(abi.encodePacked(requiredGas)));
    }
    /**
     * @dev Marks a hash as approved. This can be used to validate a hash that is used by a signature.
     * @param hashToApprove The hash that should be marked as approved for signatures that are verified by this contract.
     */
    function approveHash(bytes32 hashToApprove) external {
        require(owners[msg.sender] != address(0), "GS030");
        approvedHashes[msg.sender][hashToApprove] = 1;
        emit ApproveHash(hashToApprove, msg.sender);
    }
    /// @dev Returns the chain id used by this contract.
    function getChainId() public view returns (uint256) {
        uint256 id;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            id := chainid()
        }
        return id;
    }
    function domainSeparator() public view returns (bytes32) {
        return keccak256(abi.encode(DOMAIN_SEPARATOR_TYPEHASH, getChainId(), this));
    }
    /// @dev Returns the bytes that are hashed to be signed by owners.
    /// @param to Destination address.
    /// @param value Ether value.
    /// @param data Data payload.
    /// @param operation Operation type.
    /// @param safeTxGas Gas that should be used for the safe transaction.
    /// @param baseGas Gas costs for that are independent of the transaction execution(e.g. base transaction fee, signature check, payment of the refund)
    /// @param gasPrice Maximum gas price that should be used for this transaction.
    /// @param gasToken Token address (or 0 if ETH) that is used for the payment.
    /// @param refundReceiver Address of receiver of gas payment (or 0 if tx.origin).
    /// @param _nonce Transaction nonce.
    /// @return Transaction hash bytes.
    function encodeTransactionData(
        address to,
        uint256 value,
        bytes calldata data,
        Enum.Operation operation,
        uint256 safeTxGas,
        uint256 baseGas,
        uint256 gasPrice,
        address gasToken,
        address refundReceiver,
        uint256 _nonce
    ) public view returns (bytes memory) {
        bytes32 safeTxHash =
            keccak256(
                abi.encode(
                    SAFE_TX_TYPEHASH,
                    to,
                    value,
                    keccak256(data),
                    operation,
                    safeTxGas,
                    baseGas,
                    gasPrice,
                    gasToken,
                    refundReceiver,
                    _nonce
                )
            );
        return abi.encodePacked(bytes1(0x19), bytes1(0x01), domainSeparator(), safeTxHash);
    }
    /// @dev Returns hash to be signed by owners.
    /// @param to Destination address.
    /// @param value Ether value.
    /// @param data Data payload.
    /// @param operation Operation type.
    /// @param safeTxGas Fas that should be used for the safe transaction.
    /// @param baseGas Gas costs for data used to trigger the safe transaction.
    /// @param gasPrice Maximum gas price that should be used for this transaction.
    /// @param gasToken Token address (or 0 if ETH) that is used for the payment.
    /// @param refundReceiver Address of receiver of gas payment (or 0 if tx.origin).
    /// @param _nonce Transaction nonce.
    /// @return Transaction hash.
    function getTransactionHash(
        address to,
        uint256 value,
        bytes calldata data,
        Enum.Operation operation,
        uint256 safeTxGas,
        uint256 baseGas,
        uint256 gasPrice,
        address gasToken,
        address refundReceiver,
        uint256 _nonce
    ) public view returns (bytes32) {
        return keccak256(encodeTransactionData(to, value, data, operation, safeTxGas, baseGas, gasPrice, gasToken, refundReceiver, _nonce));
    }
}
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
import "../common/Enum.sol";
/// @title Executor - A contract that can execute transactions
/// @author Richard Meissner - <richard@gnosis.pm>
contract Executor {
    function execute(
        address to,
        uint256 value,
        bytes memory data,
        Enum.Operation operation,
        uint256 txGas
    ) internal returns (bool success) {
        if (operation == Enum.Operation.DelegateCall) {
            // solhint-disable-next-line no-inline-assembly
            assembly {
                success := delegatecall(txGas, to, add(data, 0x20), mload(data), 0, 0)
            }
        } else {
            // solhint-disable-next-line no-inline-assembly
            assembly {
                success := call(txGas, to, value, add(data, 0x20), mload(data), 0, 0)
            }
        }
    }
}
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
import "../common/SelfAuthorized.sol";
/// @title Fallback Manager - A contract that manages fallback calls made to this contract
/// @author Richard Meissner - <richard@gnosis.pm>
contract FallbackManager is SelfAuthorized {
    event ChangedFallbackHandler(address handler);
    // keccak256("fallback_manager.handler.address")
    bytes32 internal constant FALLBACK_HANDLER_STORAGE_SLOT = 0x6c9a6c4a39284e37ed1cf53d337577d14212a4870fb976a4366c693b939918d5;
    function internalSetFallbackHandler(address handler) internal {
        bytes32 slot = FALLBACK_HANDLER_STORAGE_SLOT;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            sstore(slot, handler)
        }
    }
    /// @dev Allows to add a contract to handle fallback calls.
    ///      Only fallback calls without value and with data will be forwarded.
    ///      This can only be done via a Safe transaction.
    /// @param handler contract to handle fallbacks calls.
    function setFallbackHandler(address handler) public authorized {
        internalSetFallbackHandler(handler);
        emit ChangedFallbackHandler(handler);
    }
    // solhint-disable-next-line payable-fallback,no-complex-fallback
    fallback() external {
        bytes32 slot = FALLBACK_HANDLER_STORAGE_SLOT;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            let handler := sload(slot)
            if iszero(handler) {
                return(0, 0)
            }
            calldatacopy(0, 0, calldatasize())
            // The msg.sender address is shifted to the left by 12 bytes to remove the padding
            // Then the address without padding is stored right after the calldata
            mstore(calldatasize(), shl(96, caller()))
            // Add 20 bytes for the address appended add the end
            let success := call(gas(), handler, 0, 0, add(calldatasize(), 20), 0, 0)
            returndatacopy(0, 0, returndatasize())
            if iszero(success) {
                revert(0, returndatasize())
            }
            return(0, returndatasize())
        }
    }
}
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
import "../common/Enum.sol";
import "../common/SelfAuthorized.sol";
interface Guard {
    function checkTransaction(
        address to,
        uint256 value,
        bytes memory data,
        Enum.Operation operation,
        uint256 safeTxGas,
        uint256 baseGas,
        uint256 gasPrice,
        address gasToken,
        address payable refundReceiver,
        bytes memory signatures,
        address msgSender
    ) external;
    function checkAfterExecution(bytes32 txHash, bool success) external;
}
/// @title Fallback Manager - A contract that manages fallback calls made to this contract
/// @author Richard Meissner - <richard@gnosis.pm>
contract GuardManager is SelfAuthorized {
    event ChangedGuard(address guard);
    // keccak256("guard_manager.guard.address")
    bytes32 internal constant GUARD_STORAGE_SLOT = 0x4a204f620c8c5ccdca3fd54d003badd85ba500436a431f0cbda4f558c93c34c8;
    /// @dev Set a guard that checks transactions before execution
    /// @param guard The address of the guard to be used or the 0 address to disable the guard
    function setGuard(address guard) external authorized {
        bytes32 slot = GUARD_STORAGE_SLOT;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            sstore(slot, guard)
        }
        emit ChangedGuard(guard);
    }
    function getGuard() internal view returns (address guard) {
        bytes32 slot = GUARD_STORAGE_SLOT;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            guard := sload(slot)
        }
    }
}
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
import "../common/Enum.sol";
import "../common/SelfAuthorized.sol";
import "./Executor.sol";
/// @title Module Manager - A contract that manages modules that can execute transactions via this contract
/// @author Stefan George - <stefan@gnosis.pm>
/// @author Richard Meissner - <richard@gnosis.pm>
contract ModuleManager is SelfAuthorized, Executor {
    event EnabledModule(address module);
    event DisabledModule(address module);
    event ExecutionFromModuleSuccess(address indexed module);
    event ExecutionFromModuleFailure(address indexed module);
    address internal constant SENTINEL_MODULES = address(0x1);
    mapping(address => address) internal modules;
    function setupModules(address to, bytes memory data) internal {
        require(modules[SENTINEL_MODULES] == address(0), "GS100");
        modules[SENTINEL_MODULES] = SENTINEL_MODULES;
        if (to != address(0))
            // Setup has to complete successfully or transaction fails.
            require(execute(to, 0, data, Enum.Operation.DelegateCall, gasleft()), "GS000");
    }
    /// @dev Allows to add a module to the whitelist.
    ///      This can only be done via a Safe transaction.
    /// @notice Enables the module `module` for the Safe.
    /// @param module Module to be whitelisted.
    function enableModule(address module) public authorized {
        // Module address cannot be null or sentinel.
        require(module != address(0) && module != SENTINEL_MODULES, "GS101");
        // Module cannot be added twice.
        require(modules[module] == address(0), "GS102");
        modules[module] = modules[SENTINEL_MODULES];
        modules[SENTINEL_MODULES] = module;
        emit EnabledModule(module);
    }
    /// @dev Allows to remove a module from the whitelist.
    ///      This can only be done via a Safe transaction.
    /// @notice Disables the module `module` for the Safe.
    /// @param prevModule Module that pointed to the module to be removed in the linked list
    /// @param module Module to be removed.
    function disableModule(address prevModule, address module) public authorized {
        // Validate module address and check that it corresponds to module index.
        require(module != address(0) && module != SENTINEL_MODULES, "GS101");
        require(modules[prevModule] == module, "GS103");
        modules[prevModule] = modules[module];
        modules[module] = address(0);
        emit DisabledModule(module);
    }
    /// @dev Allows a Module to execute a Safe transaction without any further confirmations.
    /// @param to Destination address of module transaction.
    /// @param value Ether value of module transaction.
    /// @param data Data payload of module transaction.
    /// @param operation Operation type of module transaction.
    function execTransactionFromModule(
        address to,
        uint256 value,
        bytes memory data,
        Enum.Operation operation
    ) public virtual returns (bool success) {
        // Only whitelisted modules are allowed.
        require(msg.sender != SENTINEL_MODULES && modules[msg.sender] != address(0), "GS104");
        // Execute transaction without further confirmations.
        success = execute(to, value, data, operation, gasleft());
        if (success) emit ExecutionFromModuleSuccess(msg.sender);
        else emit ExecutionFromModuleFailure(msg.sender);
    }
    /// @dev Allows a Module to execute a Safe transaction without any further confirmations and return data
    /// @param to Destination address of module transaction.
    /// @param value Ether value of module transaction.
    /// @param data Data payload of module transaction.
    /// @param operation Operation type of module transaction.
    function execTransactionFromModuleReturnData(
        address to,
        uint256 value,
        bytes memory data,
        Enum.Operation operation
    ) public returns (bool success, bytes memory returnData) {
        success = execTransactionFromModule(to, value, data, operation);
        // solhint-disable-next-line no-inline-assembly
        assembly {
            // Load free memory location
            let ptr := mload(0x40)
            // We allocate memory for the return data by setting the free memory location to
            // current free memory location + data size + 32 bytes for data size value
            mstore(0x40, add(ptr, add(returndatasize(), 0x20)))
            // Store the size
            mstore(ptr, returndatasize())
            // Store the data
            returndatacopy(add(ptr, 0x20), 0, returndatasize())
            // Point the return data to the correct memory location
            returnData := ptr
        }
    }
    /// @dev Returns if an module is enabled
    /// @return True if the module is enabled
    function isModuleEnabled(address module) public view returns (bool) {
        return SENTINEL_MODULES != module && modules[module] != address(0);
    }
    /// @dev Returns array of modules.
    /// @param start Start of the page.
    /// @param pageSize Maximum number of modules that should be returned.
    /// @return array Array of modules.
    /// @return next Start of the next page.
    function getModulesPaginated(address start, uint256 pageSize) external view returns (address[] memory array, address next) {
        // Init array with max page size
        array = new address[](pageSize);
        // Populate return array
        uint256 moduleCount = 0;
        address currentModule = modules[start];
        while (currentModule != address(0x0) && currentModule != SENTINEL_MODULES && moduleCount < pageSize) {
            array[moduleCount] = currentModule;
            currentModule = modules[currentModule];
            moduleCount++;
        }
        next = currentModule;
        // Set correct size of returned array
        // solhint-disable-next-line no-inline-assembly
        assembly {
            mstore(array, moduleCount)
        }
    }
}
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
import "../common/SelfAuthorized.sol";
/// @title OwnerManager - Manages a set of owners and a threshold to perform actions.
/// @author Stefan George - <stefan@gnosis.pm>
/// @author Richard Meissner - <richard@gnosis.pm>
contract OwnerManager is SelfAuthorized {
    event AddedOwner(address owner);
    event RemovedOwner(address owner);
    event ChangedThreshold(uint256 threshold);
    address internal constant SENTINEL_OWNERS = address(0x1);
    mapping(address => address) internal owners;
    uint256 internal ownerCount;
    uint256 internal threshold;
    /// @dev Setup function sets initial storage of contract.
    /// @param _owners List of Safe owners.
    /// @param _threshold Number of required confirmations for a Safe transaction.
    function setupOwners(address[] memory _owners, uint256 _threshold) internal {
        // Threshold can only be 0 at initialization.
        // Check ensures that setup function can only be called once.
        require(threshold == 0, "GS200");
        // Validate that threshold is smaller than number of added owners.
        require(_threshold <= _owners.length, "GS201");
        // There has to be at least one Safe owner.
        require(_threshold >= 1, "GS202");
        // Initializing Safe owners.
        address currentOwner = SENTINEL_OWNERS;
        for (uint256 i = 0; i < _owners.length; i++) {
            // Owner address cannot be null.
            address owner = _owners[i];
            require(owner != address(0) && owner != SENTINEL_OWNERS && owner != address(this) && currentOwner != owner, "GS203");
            // No duplicate owners allowed.
            require(owners[owner] == address(0), "GS204");
            owners[currentOwner] = owner;
            currentOwner = owner;
        }
        owners[currentOwner] = SENTINEL_OWNERS;
        ownerCount = _owners.length;
        threshold = _threshold;
    }
    /// @dev Allows to add a new owner to the Safe and update the threshold at the same time.
    ///      This can only be done via a Safe transaction.
    /// @notice Adds the owner `owner` to the Safe and updates the threshold to `_threshold`.
    /// @param owner New owner address.
    /// @param _threshold New threshold.
    function addOwnerWithThreshold(address owner, uint256 _threshold) public authorized {
        // Owner address cannot be null, the sentinel or the Safe itself.
        require(owner != address(0) && owner != SENTINEL_OWNERS && owner != address(this), "GS203");
        // No duplicate owners allowed.
        require(owners[owner] == address(0), "GS204");
        owners[owner] = owners[SENTINEL_OWNERS];
        owners[SENTINEL_OWNERS] = owner;
        ownerCount++;
        emit AddedOwner(owner);
        // Change threshold if threshold was changed.
        if (threshold != _threshold) changeThreshold(_threshold);
    }
    /// @dev Allows to remove an owner from the Safe and update the threshold at the same time.
    ///      This can only be done via a Safe transaction.
    /// @notice Removes the owner `owner` from the Safe and updates the threshold to `_threshold`.
    /// @param prevOwner Owner that pointed to the owner to be removed in the linked list
    /// @param owner Owner address to be removed.
    /// @param _threshold New threshold.
    function removeOwner(
        address prevOwner,
        address owner,
        uint256 _threshold
    ) public authorized {
        // Only allow to remove an owner, if threshold can still be reached.
        require(ownerCount - 1 >= _threshold, "GS201");
        // Validate owner address and check that it corresponds to owner index.
        require(owner != address(0) && owner != SENTINEL_OWNERS, "GS203");
        require(owners[prevOwner] == owner, "GS205");
        owners[prevOwner] = owners[owner];
        owners[owner] = address(0);
        ownerCount--;
        emit RemovedOwner(owner);
        // Change threshold if threshold was changed.
        if (threshold != _threshold) changeThreshold(_threshold);
    }
    /// @dev Allows to swap/replace an owner from the Safe with another address.
    ///      This can only be done via a Safe transaction.
    /// @notice Replaces the owner `oldOwner` in the Safe with `newOwner`.
    /// @param prevOwner Owner that pointed to the owner to be replaced in the linked list
    /// @param oldOwner Owner address to be replaced.
    /// @param newOwner New owner address.
    function swapOwner(
        address prevOwner,
        address oldOwner,
        address newOwner
    ) public authorized {
        // Owner address cannot be null, the sentinel or the Safe itself.
        require(newOwner != address(0) && newOwner != SENTINEL_OWNERS && newOwner != address(this), "GS203");
        // No duplicate owners allowed.
        require(owners[newOwner] == address(0), "GS204");
        // Validate oldOwner address and check that it corresponds to owner index.
        require(oldOwner != address(0) && oldOwner != SENTINEL_OWNERS, "GS203");
        require(owners[prevOwner] == oldOwner, "GS205");
        owners[newOwner] = owners[oldOwner];
        owners[prevOwner] = newOwner;
        owners[oldOwner] = address(0);
        emit RemovedOwner(oldOwner);
        emit AddedOwner(newOwner);
    }
    /// @dev Allows to update the number of required confirmations by Safe owners.
    ///      This can only be done via a Safe transaction.
    /// @notice Changes the threshold of the Safe to `_threshold`.
    /// @param _threshold New threshold.
    function changeThreshold(uint256 _threshold) public authorized {
        // Validate that threshold is smaller than number of owners.
        require(_threshold <= ownerCount, "GS201");
        // There has to be at least one Safe owner.
        require(_threshold >= 1, "GS202");
        threshold = _threshold;
        emit ChangedThreshold(threshold);
    }
    function getThreshold() public view returns (uint256) {
        return threshold;
    }
    function isOwner(address owner) public view returns (bool) {
        return owner != SENTINEL_OWNERS && owners[owner] != address(0);
    }
    /// @dev Returns array of owners.
    /// @return Array of Safe owners.
    function getOwners() public view returns (address[] memory) {
        address[] memory array = new address[](ownerCount);
        // populate return array
        uint256 index = 0;
        address currentOwner = owners[SENTINEL_OWNERS];
        while (currentOwner != SENTINEL_OWNERS) {
            array[index] = currentOwner;
            currentOwner = owners[currentOwner];
            index++;
        }
        return array;
    }
}
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
/// @title Enum - Collection of enums
/// @author Richard Meissner - <richard@gnosis.pm>
contract Enum {
    enum Operation {Call, DelegateCall}
}
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
/// @title EtherPaymentFallback - A contract that has a fallback to accept ether payments
/// @author Richard Meissner - <richard@gnosis.pm>
contract EtherPaymentFallback {
    event SafeReceived(address indexed sender, uint256 value);
    /// @dev Fallback function accepts Ether transactions.
    receive() external payable {
        emit SafeReceived(msg.sender, msg.value);
    }
}
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
/// @title SecuredTokenTransfer - Secure token transfer
/// @author Richard Meissner - <richard@gnosis.pm>
contract SecuredTokenTransfer {
    /// @dev Transfers a token and returns if it was a success
    /// @param token Token that should be transferred
    /// @param receiver Receiver to whom the token should be transferred
    /// @param amount The amount of tokens that should be transferred
    function transferToken(
        address token,
        address receiver,
        uint256 amount
    ) internal returns (bool transferred) {
        // 0xa9059cbb - keccack("transfer(address,uint256)")
        bytes memory data = abi.encodeWithSelector(0xa9059cbb, receiver, amount);
        // solhint-disable-next-line no-inline-assembly
        assembly {
            // We write the return value to scratch space.
            // See https://docs.soliditylang.org/en/v0.7.6/internals/layout_in_memory.html#layout-in-memory
            let success := call(sub(gas(), 10000), token, 0, add(data, 0x20), mload(data), 0, 0x20)
            switch returndatasize()
                case 0 {
                    transferred := success
                }
                case 0x20 {
                    transferred := iszero(or(iszero(success), iszero(mload(0))))
                }
                default {
                    transferred := 0
                }
        }
    }
}
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
/// @title SelfAuthorized - authorizes current contract to perform actions
/// @author Richard Meissner - <richard@gnosis.pm>
contract SelfAuthorized {
    function requireSelfCall() private view {
        require(msg.sender == address(this), "GS031");
    }
    modifier authorized() {
        // This is a function call as it minimized the bytecode size
        requireSelfCall();
        _;
    }
}
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
/// @title SignatureDecoder - Decodes signatures that a encoded as bytes
/// @author Richard Meissner - <richard@gnosis.pm>
contract SignatureDecoder {
    /// @dev divides bytes signature into `uint8 v, bytes32 r, bytes32 s`.
    /// @notice Make sure to peform a bounds check for @param pos, to avoid out of bounds access on @param signatures
    /// @param pos which signature to read. A prior bounds check of this parameter should be performed, to avoid out of bounds access
    /// @param signatures concatenated rsv signatures
    function signatureSplit(bytes memory signatures, uint256 pos)
        internal
        pure
        returns (
            uint8 v,
            bytes32 r,
            bytes32 s
        )
    {
        // The signature format is a compact form of:
        //   {bytes32 r}{bytes32 s}{uint8 v}
        // Compact means, uint8 is not padded to 32 bytes.
        // solhint-disable-next-line no-inline-assembly
        assembly {
            let signaturePos := mul(0x41, pos)
            r := mload(add(signatures, add(signaturePos, 0x20)))
            s := mload(add(signatures, add(signaturePos, 0x40)))
            // Here we are loading the last 32 bytes, including 31 bytes
            // of 's'. There is no 'mload8' to do this.
            //
            // 'byte' is not working due to the Solidity parser, so lets
            // use the second best option, 'and'
            v := and(mload(add(signatures, add(signaturePos, 0x41))), 0xff)
        }
    }
}
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
/// @title Singleton - Base for singleton contracts (should always be first super contract)
///         This contract is tightly coupled to our proxy contract (see `proxies/GnosisSafeProxy.sol`)
/// @author Richard Meissner - <richard@gnosis.io>
contract Singleton {
    // singleton always needs to be first declared variable, to ensure that it is at the same location as in the Proxy contract.
    // It should also always be ensured that the address is stored alone (uses a full word)
    address private singleton;
}
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
/// @title StorageAccessible - generic base contract that allows callers to access all internal storage.
/// @notice See https://github.com/gnosis/util-contracts/blob/bb5fe5fb5df6d8400998094fb1b32a178a47c3a1/contracts/StorageAccessible.sol
contract StorageAccessible {
    /**
     * @dev Reads `length` bytes of storage in the currents contract
     * @param offset - the offset in the current contract's storage in words to start reading from
     * @param length - the number of words (32 bytes) of data to read
     * @return the bytes that were read.
     */
    function getStorageAt(uint256 offset, uint256 length) public view returns (bytes memory) {
        bytes memory result = new bytes(length * 32);
        for (uint256 index = 0; index < length; index++) {
            // solhint-disable-next-line no-inline-assembly
            assembly {
                let word := sload(add(offset, index))
                mstore(add(add(result, 0x20), mul(index, 0x20)), word)
            }
        }
        return result;
    }
    /**
     * @dev Performs a delegetecall on a targetContract in the context of self.
     * Internally reverts execution to avoid side effects (making it static).
     *
     * This method reverts with data equal to `abi.encode(bool(success), bytes(response))`.
     * Specifically, the `returndata` after a call to this method will be:
     * `success:bool || response.length:uint256 || response:bytes`.
     *
     * @param targetContract Address of the contract containing the code to execute.
     * @param calldataPayload Calldata that should be sent to the target contract (encoded method name and arguments).
     */
    function simulateAndRevert(address targetContract, bytes memory calldataPayload) external {
        // solhint-disable-next-line no-inline-assembly
        assembly {
            let success := delegatecall(gas(), targetContract, add(calldataPayload, 0x20), mload(calldataPayload), 0, 0)
            mstore(0x00, success)
            mstore(0x20, returndatasize())
            returndatacopy(0x40, 0, returndatasize())
            revert(0, add(returndatasize(), 0x40))
        }
    }
}
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
/**
 * @title GnosisSafeMath
 * @dev Math operations with safety checks that revert on error
 * Renamed from SafeMath to GnosisSafeMath to avoid conflicts
 * TODO: remove once open zeppelin update to solc 0.5.0
 */
library GnosisSafeMath {
    /**
     * @dev Multiplies two numbers, reverts on overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // 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-solidity/pull/522
        if (a == 0) {
            return 0;
        }
        uint256 c = a * b;
        require(c / a == b);
        return c;
    }
    /**
     * @dev Subtracts two numbers, reverts on overflow (i.e. if subtrahend is greater than minuend).
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a);
        uint256 c = a - b;
        return c;
    }
    /**
     * @dev Adds two numbers, reverts on overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a);
        return c;
    }
    /**
     * @dev Returns the largest of two numbers.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a >= b ? a : b;
    }
}
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
contract ISignatureValidatorConstants {
    // bytes4(keccak256("isValidSignature(bytes,bytes)")
    bytes4 internal constant EIP1271_MAGIC_VALUE = 0x20c13b0b;
}
abstract contract ISignatureValidator is ISignatureValidatorConstants {
    /**
     * @dev Should return whether the signature provided is valid for the provided data
     * @param _data Arbitrary length data signed on the behalf of address(this)
     * @param _signature Signature byte array associated with _data
     *
     * MUST return the bytes4 magic value 0x20c13b0b when function passes.
     * MUST NOT modify state (using STATICCALL for solc < 0.5, view modifier for solc > 0.5)
     * MUST allow external calls
     */
    function isValidSignature(bytes memory _data, bytes memory _signature) public view virtual returns (bytes4);
}