// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)

pragma solidity ^0.8.1;

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

        return account.code.length > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://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 functionCallWithValue(target, data, 0, "Address: low-level call failed");
    }

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

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

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

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

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

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

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

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

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

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

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

pragma solidity ^0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// SPDX-License-Identifier: MIT
/**
  ______ _____   _____ ______ ___  __ _  _  _
 |  ____|  __ \ / ____|____  |__ \/_ | || || |
 | |__  | |__) | |        / /   ) || | \| |/ |
 |  __| |  _  /| |       / /   / / | |\_   _/
 | |____| | \ \| |____  / /   / /_ | |  | |
 |______|_|  \_\\_____|/_/   |____||_|  |_|

 - github: https://github.com/estarriolvetch/ERC721Psi
 - npm: https://www.npmjs.com/package/erc721psi

 */

pragma solidity ^0.8.0;

import "@openzeppelin/contracts/utils/Strings.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "solady/src/utils/LibBitmap.sol";
import "./interface/IERC721Psi.sol";

/**
 * @dev Interface of ERC721 token receiver.
 */
interface ERC721Psi__IERC721Receiver {
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
}

contract ERC721Psi is IERC721Psi {

    using Address for address;
    using Strings for uint256;
    using LibBitmap for LibBitmap.Bitmap;

    LibBitmap.Bitmap private _batchHead;

    string private _name;
    string private _symbol;

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

    mapping(uint256 => address) private _tokenApprovals;
    mapping(address => mapping(address => bool)) private _operatorApprovals;

    // The mask of the lower 160 bits for addresses.
    uint256 private constant _BITMASK_ADDRESS = (1 << 160) - 1;
    // The `Transfer` event signature is given by:
    // `keccak256(bytes("Transfer(address,address,uint256)"))`.
    bytes32 private constant _TRANSFER_EVENT_SIGNATURE =
        0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef;

    /**
     * @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_;
        _currentIndex = _startTokenId();
    }

    /**
     * @dev Returns the starting token ID.
     * To change the starting token ID, please override this function.
     */
    function _startTokenId() internal view virtual returns (uint256) {
        return 0;
    }

    /**
     * @dev Returns the next token ID to be minted.
     */
    function _nextTokenId() internal view virtual returns (uint256) {
        return _currentIndex;
    }

    /**
     * @dev Returns the total amount of tokens minted in the contract.
     */
    function _totalMinted() internal view virtual returns (uint256) {
        return _currentIndex - _startTokenId();
    }


    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * [EIP section](https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified)
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30000 gas.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        // The interface IDs are constants representing the first 4 bytes
        // of the XOR of all function selectors in the interface.
        // See: [ERC165](https://eips.ethereum.org/EIPS/eip-165)
        // (e.g. `bytes4(i.functionA.selector ^ i.functionB.selector ^ ...)`)
        return
            interfaceId == 0x01ffc9a7 || // ERC165 interface ID for ERC165.
            interfaceId == 0x80ac58cd || // ERC165 interface ID for ERC721.
            interfaceId == 0x5b5e139f; // ERC165 interface ID for ERC721Metadata.
    }

    /**
     * @dev See {IERC721-balanceOf}.
     */
    function balanceOf(address owner)
        public
        view
        virtual
        override
        returns (uint)
    {
        if(owner == address(0)) revert BalanceQueryForZeroAddress();

        uint count;
        for( uint i = _startTokenId(); i < _nextTokenId(); ++i ){
            if(_exists(i)){
                if( owner == ownerOf(i)){
                    ++count;
                }
            }
        }
        return count;
    }

    /**
     * @dev See {IERC721-ownerOf}.
     */
    function ownerOf(uint256 tokenId)
        public
        view
        virtual
        override
        returns (address)
    {
        (address owner, ) = _ownerAndBatchHeadOf(tokenId);
        return owner;
    }

    function _ownerAndBatchHeadOf(uint256 tokenId) internal view returns (address owner, uint256 tokenIdBatchHead){
        if (!_exists(tokenId)) revert OwnerQueryForNonexistentToken();
        tokenIdBatchHead = _getBatchHead(tokenId);
        owner = _owners[tokenIdBatchHead];
    }

    /**
     * @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) {
        if( !_exists(tokenId)) revert URIQueryForNonexistentToken();
        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 payable virtual override {
        address owner = ownerOf(tokenId);

        if (_msgSenderERC721Psi() != owner) {
            if (!isApprovedForAll(owner, _msgSenderERC721Psi())) {
                revert ApprovalCallerNotOwnerNorApproved();
            }
        }

        _approve(to, tokenId);
    }

    /**
     * @dev See {IERC721-getApproved}.
     */
    function getApproved(uint256 tokenId)
        public
        view
        virtual
        override
        returns (address)
    {
        if (!_exists(tokenId)) revert ApprovalQueryForNonexistentToken();

        return _tokenApprovals[tokenId];
    }

    /**
     * @dev See {IERC721-setApprovalForAll}.
     */
    function setApprovalForAll(address operator, bool approved)
        public
        virtual
        override
    {
        _operatorApprovals[_msgSenderERC721Psi()][operator] = approved;
        emit ApprovalForAll(_msgSenderERC721Psi(), 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 payable virtual override {
        _transfer(from, to, tokenId);
    }

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

    /**
     * @dev See {IERC721-safeTransferFrom}.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes memory _data
    ) public payable virtual override {
        _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);
        if (!_checkOnERC721Received(from, to, tokenId, 1, _data)) {
            revert TransferToNonERC721ReceiverImplementer();
        }
    }

    /**
     * @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`).
     */
    function _exists(uint256 tokenId) internal view virtual returns (bool) {
        return tokenId < _nextTokenId() && _startTokenId() <= tokenId;
    }

    /**
     * @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),
            "ERC721Psi: operator query for nonexistent token"
        );
        address owner = ownerOf(tokenId);
        return (spender == owner ||
            getApproved(tokenId) == spender ||
            isApprovedForAll(owner, spender));
    }

    /**
     * @dev Safely mints `quantity` tokens and transfers them to `to`.
     *
     * Requirements:
     *
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called for each safe transfer.
     * - `quantity` must be greater than 0.
     *
     * Emits a {Transfer} event.
     */
    function _safeMint(address to, uint256 quantity) internal virtual {
        _safeMint(to, quantity, "");
    }


    function _safeMint(
        address to,
        uint256 quantity,
        bytes memory _data
    ) internal virtual {
        _mint(to, quantity);
        uint256 end = _currentIndex;
        if (!_checkOnERC721Received(address(0), to, end - quantity, quantity, _data)) {
            revert TransferToNonERC721ReceiverImplementer();
        }
        // Reentrancy protection.
        if (_currentIndex != end) revert();
    }


    function _mint(
        address to,
        uint256 quantity
    ) internal virtual {
        uint256 nextTokenId = _nextTokenId();

        if (quantity == 0) revert MintZeroQuantity();
        if (to == address(0)) revert MintToZeroAddress();

        _beforeTokenTransfers(address(0), to, nextTokenId, quantity);
        _currentIndex += quantity;
        _owners[nextTokenId] = to;
        _batchHead.set(nextTokenId);

        uint256 toMasked;
        uint256 end = nextTokenId + quantity;

        // Use assembly to loop and emit the `Transfer` event for gas savings.
        // The duplicated `log4` removes an extra check and reduces stack juggling.
        // The assembly, together with the surrounding Solidity code, have been
        // delicately arranged to nudge the compiler into producing optimized opcodes.
        assembly {
            // Mask `to` to the lower 160 bits, in case the upper bits somehow aren't clean.
            toMasked := and(to, _BITMASK_ADDRESS)
            // Emit the `Transfer` event.
            log4(
                0, // Start of data (0, since no data).
                0, // End of data (0, since no data).
                _TRANSFER_EVENT_SIGNATURE, // Signature.
                0, // `address(0)`.
                toMasked, // `to`.
                nextTokenId // `tokenId`.
            )

            // The `iszero(eq(,))` check ensures that large values of `quantity`
            // that overflows uint256 will make the loop run out of gas.
            // The compiler will optimize the `iszero` away for performance.
            for {
                let tokenId := add(nextTokenId, 1)
            } iszero(eq(tokenId, end)) {
                tokenId := add(tokenId, 1)
            } {
                // Emit the `Transfer` event. Similar to above.
                log4(0, 0, _TRANSFER_EVENT_SIGNATURE, 0, toMasked, tokenId)
            }
        }

        _afterTokenTransfers(address(0), to, nextTokenId, quantity);
    }


    /**
     * @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 {

        (address owner, uint256 tokenIdBatchHead) = _ownerAndBatchHeadOf(tokenId);

        if (owner != from) revert TransferFromIncorrectOwner();

        if (!_isApprovedOrOwner(_msgSenderERC721Psi(), tokenId)) {
            revert TransferCallerNotOwnerNorApproved();
        }

        if (to == address(0)) revert TransferToZeroAddress();

        _beforeTokenTransfers(from, to, tokenId, 1);

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

        uint256 subsequentTokenId = tokenId + 1;

        if(!_batchHead.get(subsequentTokenId) &&
            subsequentTokenId < _nextTokenId()
        ) {
            _owners[subsequentTokenId] = from;
            _batchHead.set(subsequentTokenId);
        }

        _owners[tokenId] = to;
        if(tokenId != tokenIdBatchHead) {
            _batchHead.set(tokenId);
        }

        emit Transfer(from, to, tokenId);

        _afterTokenTransfers(from, to, tokenId, 1);
    }

    /**
     * @dev Approve `to` to operate on `tokenId`
     *
     * Emits a {Approval} event.
     */
    function _approve(address to, uint256 tokenId) internal virtual {
        _tokenApprovals[tokenId] = to;
        emit Approval(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 startTokenId uint256 the first ID of the tokens to be transferred
     * @param quantity uint256 amount of the tokens to be transfered.
     * @param _data bytes optional data to send along with the call
     * @return r bool whether the call correctly returned the expected magic value
     */
    function _checkOnERC721Received(
        address from,
        address to,
        uint256 startTokenId,
        uint256 quantity,
        bytes memory _data
    ) private returns (bool r) {
        if (to.isContract()) {
            r = true;
            for(uint256 tokenId = startTokenId; tokenId < startTokenId + quantity; tokenId++){
                try ERC721Psi__IERC721Receiver(to).onERC721Received( _msgSenderERC721Psi(), from, tokenId, _data) returns (bytes4 retval) {
                    r = r && retval == ERC721Psi__IERC721Receiver.onERC721Received.selector;
                } catch (bytes memory reason) {
                    if (reason.length == 0) {
                        revert TransferToNonERC721ReceiverImplementer();
                    } else {
                        assembly {
                            revert(add(32, reason), mload(reason))
                        }
                    }
                }
            }
            return r;
        } else {
            return true;
        }
    }

    function _getBatchHead(uint256 tokenId) internal view returns (uint256 tokenIdBatchHead) {
        tokenIdBatchHead = _batchHead.findLastSet(tokenId);
    }


    function totalSupply() public virtual override view returns (uint256) {
        return _totalMinted();
    }

    /**
     * @dev Returns an array of token IDs owned by `owner`.
     *
     * This function scans the ownership mapping and is O(`totalSupply`) in complexity.
     * It is meant to be called off-chain.
     *
     * This function is compatiable with ERC721AQueryable.
     */
    function tokensOfOwner(address owner) external view virtual returns (uint256[] memory) {
        unchecked {
            uint256 tokenIdsIdx;
            uint256 tokenIdsLength = balanceOf(owner);
            uint256[] memory tokenIds = new uint256[](tokenIdsLength);
            for (uint256 i = _startTokenId(); tokenIdsIdx != tokenIdsLength; ++i) {
                if (_exists(i)) {
                    if (ownerOf(i) == owner) {
                        tokenIds[tokenIdsIdx++] = i;
                    }
                }
            }
            return tokenIds;
        }
    }

    /**
     * @dev Hook that is called before a set of serially-ordered token ids are about to be transferred. This includes minting.
     *
     * startTokenId - the first token id to be transferred
     * quantity - the amount to be transferred
     *
     * 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`.
     */
    function _beforeTokenTransfers(
        address from,
        address to,
        uint256 startTokenId,
        uint256 quantity
    ) internal virtual {}

    /**
     * @dev Hook that is called after a set of serially-ordered token ids have been transferred. This includes
     * minting.
     *
     * startTokenId - the first token id to be transferred
     * quantity - the amount to be transferred
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero.
     * - `from` and `to` are never both zero.
     */
    function _afterTokenTransfers(
        address from,
        address to,
        uint256 startTokenId,
        uint256 quantity
    ) internal virtual {}


    /**
     * @dev Returns the message sender (defaults to `msg.sender`).
     *
     * If you are writing GSN compatible contracts, you need to override this function.
     */
    function _msgSenderERC721Psi() internal view virtual returns (address) {
        return msg.sender;
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Interface of ERC721Psi.
 */
interface IERC721Psi {
    /**
     * The caller must own the token or be an approved operator.
     */
    error ApprovalCallerNotOwnerNorApproved();

    /**
     * The token does not exist.
     */
    error ApprovalQueryForNonexistentToken();

    /**
     * Cannot query the balance for the zero address.
     */
    error BalanceQueryForZeroAddress();

    /**
     * Cannot mint to the zero address.
     */
    error MintToZeroAddress();

    /**
     * The quantity of tokens minted must be more than zero.
     */
    error MintZeroQuantity();

    /**
     * The token does not exist.
     */
    error OwnerQueryForNonexistentToken();

    /**
     * The caller must own the token or be an approved operator.
     */
    error TransferCallerNotOwnerNorApproved();

    /**
     * The token must be owned by `from`.
     */
    error TransferFromIncorrectOwner();

    /**
     * Cannot safely transfer to a contract that does not implement the
     * ERC721Receiver interface.
     */
    error TransferToNonERC721ReceiverImplementer();

    /**
     * Cannot transfer to the zero address.
     */
    error TransferToZeroAddress();

    /**
     * The token does not exist.
     */
    error URIQueryForNonexistentToken();


    // =============================================================
    //                         TOKEN COUNTERS
    // =============================================================

    /**
     * @dev Returns the total number of tokens in existence.
     * Burned tokens will reduce the count.
     * To get the total number of tokens minted, please see {_totalMinted}.
     */
    function totalSupply() external view returns (uint256);

    // =============================================================
    //                            IERC165
    // =============================================================

    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * [EIP section](https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified)
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);

    // =============================================================
    //                            IERC721
    // =============================================================

    /**
     * @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,
        bytes calldata data
    ) external payable;

    /**
     * @dev Equivalent to `safeTransferFrom(from, to, tokenId, '')`.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external payable;

    /**
     * @dev Transfers `tokenId` 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 payable;

    /**
     * @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 payable;

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

    /**
     * @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);

    // =============================================================
    //                        IERC721Metadata
    // =============================================================

    /**
     * @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);
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

/// @notice Library for bit twiddling operations.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/LibBit.sol)
/// @author Inspired by (https://graphics.stanford.edu/~seander/bithacks.html)
library LibBit {
    /// @dev Find last set.
    /// Returns the index of the most significant bit of `x`,
    /// counting from the least significant bit position.
    /// If `x` is zero, returns 256.
    /// Equivalent to `log2(x)`, but without reverting for the zero case.
    function fls(uint256 x) internal pure returns (uint256 r) {
        /// @solidity memory-safe-assembly
        assembly {
            r := shl(8, iszero(x))

            r := or(r, shl(7, lt(0xffffffffffffffffffffffffffffffff, x)))
            r := or(r, shl(6, lt(0xffffffffffffffff, shr(r, x))))
            r := or(r, shl(5, lt(0xffffffff, shr(r, x))))

            // For the remaining 32 bits, use a De Bruijn lookup.
            x := shr(r, x)
            x := or(x, shr(1, x))
            x := or(x, shr(2, x))
            x := or(x, shr(4, x))
            x := or(x, shr(8, x))
            x := or(x, shr(16, x))

            // forgefmt: disable-next-item
            r := or(r, byte(shr(251, mul(x, shl(224, 0x07c4acdd))),
                0x0009010a0d15021d0b0e10121619031e080c141c0f111807131b17061a05041f))
        }
    }

    /// @dev Count leading zeros.
    /// Returns the number of zeros preceding the most significant one bit.
    /// If `x` is zero, returns 256.
    function clz(uint256 x) internal pure returns (uint256 r) {
        /// @solidity memory-safe-assembly
        assembly {
            let t := add(iszero(x), 255)

            r := shl(7, lt(0xffffffffffffffffffffffffffffffff, x))
            r := or(r, shl(6, lt(0xffffffffffffffff, shr(r, x))))
            r := or(r, shl(5, lt(0xffffffff, shr(r, x))))

            // For the remaining 32 bits, use a De Bruijn lookup.
            x := shr(r, x)
            x := or(x, shr(1, x))
            x := or(x, shr(2, x))
            x := or(x, shr(4, x))
            x := or(x, shr(8, x))
            x := or(x, shr(16, x))

            // forgefmt: disable-next-item
            r := sub(t, or(r, byte(shr(251, mul(x, shl(224, 0x07c4acdd))),
                0x0009010a0d15021d0b0e10121619031e080c141c0f111807131b17061a05041f)))
        }
    }

    /// @dev Find first set.
    /// Returns the index of the least significant bit of `x`,
    /// counting from the least significant bit position.
    /// If `x` is zero, returns 256.
    /// Equivalent to `ctz` (count trailing zeros), which gives
    /// the number of zeros following the least significant one bit.
    function ffs(uint256 x) internal pure returns (uint256 r) {
        /// @solidity memory-safe-assembly
        assembly {
            r := shl(8, iszero(x))

            // Isolate the least significant bit.
            x := and(x, add(not(x), 1))

            r := or(r, shl(7, lt(0xffffffffffffffffffffffffffffffff, x)))
            r := or(r, shl(6, lt(0xffffffffffffffff, shr(r, x))))
            r := or(r, shl(5, lt(0xffffffff, shr(r, x))))

            // For the remaining 32 bits, use a De Bruijn lookup.
            // forgefmt: disable-next-item
            r := or(r, byte(shr(251, mul(shr(r, x), shl(224, 0x077cb531))), 
                0x00011c021d0e18031e16140f191104081f1b0d17151310071a0c12060b050a09))
        }
    }

    /// @dev Returns the number of set bits in `x`.
    function popCount(uint256 x) internal pure returns (uint256 c) {
        /// @solidity memory-safe-assembly
        assembly {
            let max := not(0)
            let isMax := eq(x, max)
            x := sub(x, and(shr(1, x), div(max, 3)))
            x := add(and(x, div(max, 5)), and(shr(2, x), div(max, 5)))
            x := and(add(x, shr(4, x)), div(max, 17))
            c := or(shl(8, isMax), shr(248, mul(x, div(max, 255))))
        }
    }

    /// @dev Returns whether `x` is a power of 2.
    function isPo2(uint256 x) internal pure returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            // Equivalent to `x && !(x & (x - 1))`.
            result := iszero(add(and(x, sub(x, 1)), iszero(x)))
        }
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

import "./LibBit.sol";

/// @notice Library for storage of packed unsigned booleans.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/LibBitmap.sol)
/// @author Modified from Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/LibBitmap.sol)
/// @author Modified from Solidity-Bits (https://github.com/estarriolvetch/solidity-bits/blob/main/contracts/BitMaps.sol)
library LibBitmap {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                         CONSTANTS                          */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The constant returned when a bitmap scan does not find a result.
    uint256 internal constant NOT_FOUND = type(uint256).max;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                          STRUCTS                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev A bitmap in storage.
    struct Bitmap {
        mapping(uint256 => uint256) map;
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                         OPERATIONS                         */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the boolean value of the bit at `index` in `bitmap`.
    function get(Bitmap storage bitmap, uint256 index) internal view returns (bool isSet) {
        // It is better to set `isSet` to either 0 or 1, than zero vs non-zero.
        // Both cost the same amount of gas, but the former allows the returned value
        // to be reused without cleaning the upper bits.
        uint256 b = (bitmap.map[index >> 8] >> (index & 0xff)) & 1;
        /// @solidity memory-safe-assembly
        assembly {
            isSet := b
        }
    }

    /// @dev Updates the bit at `index` in `bitmap` to true.
    function set(Bitmap storage bitmap, uint256 index) internal {
        bitmap.map[index >> 8] |= (1 << (index & 0xff));
    }

    /// @dev Updates the bit at `index` in `bitmap` to false.
    function unset(Bitmap storage bitmap, uint256 index) internal {
        bitmap.map[index >> 8] &= ~(1 << (index & 0xff));
    }

    /// @dev Flips the bit at `index` in `bitmap`.
    /// Returns the boolean result of the flipped bit.
    function toggle(Bitmap storage bitmap, uint256 index) internal returns (bool newIsSet) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, shr(8, index))
            mstore(0x20, bitmap.slot)
            let storageSlot := keccak256(0x00, 0x40)
            let shift := and(index, 0xff)
            let storageValue := sload(storageSlot)

            let mask := shl(shift, 1)
            storageValue := xor(storageValue, mask)
            // It makes sense to return the `newIsSet`,
            // as it allow us to skip an additional warm `sload`,
            // and it costs minimal gas (about 15),
            // which may be optimized away if the returned value is unused.
            newIsSet := iszero(iszero(and(storageValue, mask)))
            sstore(storageSlot, storageValue)
        }
    }

    /// @dev Updates the bit at `index` in `bitmap` to `shouldSet`.
    function setTo(Bitmap storage bitmap, uint256 index, bool shouldSet) internal {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x20, bitmap.slot)
            mstore(0x00, shr(8, index))
            let storageSlot := keccak256(0x00, 0x40)
            let storageValue := sload(storageSlot)
            let shift := and(index, 0xff)

            sstore(
                storageSlot,
                // Unsets the bit at `shift` via `and`, then sets its new value via `or`.
                or(and(storageValue, not(shl(shift, 1))), shl(shift, iszero(iszero(shouldSet))))
            )
        }
    }

    /// @dev Consecutively sets `amount` of bits starting from the bit at `start`.
    function setBatch(Bitmap storage bitmap, uint256 start, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            let max := not(0)
            let shift := and(start, 0xff)
            mstore(0x20, bitmap.slot)
            mstore(0x00, shr(8, start))
            if iszero(lt(add(shift, amount), 257)) {
                let storageSlot := keccak256(0x00, 0x40)
                sstore(storageSlot, or(sload(storageSlot), shl(shift, max)))
                let bucket := add(mload(0x00), 1)
                let bucketEnd := add(mload(0x00), shr(8, add(amount, shift)))
                amount := and(add(amount, shift), 0xff)
                shift := 0
                for {} iszero(eq(bucket, bucketEnd)) { bucket := add(bucket, 1) } {
                    mstore(0x00, bucket)
                    sstore(keccak256(0x00, 0x40), max)
                }
                mstore(0x00, bucket)
            }
            let storageSlot := keccak256(0x00, 0x40)
            sstore(storageSlot, or(sload(storageSlot), shl(shift, shr(sub(256, amount), max))))
        }
    }

    /// @dev Consecutively unsets `amount` of bits starting from the bit at `start`.
    function unsetBatch(Bitmap storage bitmap, uint256 start, uint256 amount) internal {
        /// @solidity memory-safe-assembly
        assembly {
            let shift := and(start, 0xff)
            mstore(0x20, bitmap.slot)
            mstore(0x00, shr(8, start))
            if iszero(lt(add(shift, amount), 257)) {
                let storageSlot := keccak256(0x00, 0x40)
                sstore(storageSlot, and(sload(storageSlot), not(shl(shift, not(0)))))
                let bucket := add(mload(0x00), 1)
                let bucketEnd := add(mload(0x00), shr(8, add(amount, shift)))
                amount := and(add(amount, shift), 0xff)
                shift := 0
                for {} iszero(eq(bucket, bucketEnd)) { bucket := add(bucket, 1) } {
                    mstore(0x00, bucket)
                    sstore(keccak256(0x00, 0x40), 0)
                }
                mstore(0x00, bucket)
            }
            let storageSlot := keccak256(0x00, 0x40)
            sstore(
                storageSlot, and(sload(storageSlot), not(shl(shift, shr(sub(256, amount), not(0)))))
            )
        }
    }

    /// @dev Returns number of set bits within a range by
    /// scanning `amount` of bits starting from the bit at `start`.
    function popCount(Bitmap storage bitmap, uint256 start, uint256 amount)
        internal
        view
        returns (uint256 count)
    {
        unchecked {
            uint256 bucket = start >> 8;
            uint256 shift = start & 0xff;
            if (!(amount + shift < 257)) {
                count = LibBit.popCount(bitmap.map[bucket] >> shift);
                uint256 bucketEnd = bucket + ((amount + shift) >> 8);
                amount = (amount + shift) & 0xff;
                shift = 0;
                for (++bucket; bucket != bucketEnd; ++bucket) {
                    count += LibBit.popCount(bitmap.map[bucket]);
                }
            }
            count += LibBit.popCount((bitmap.map[bucket] >> shift) << (256 - amount));
        }
    }

    /// @dev Returns the index of the most significant set bit before the bit at `before`.
    /// If no set bit is found, returns `NOT_FOUND`.
    function findLastSet(Bitmap storage bitmap, uint256 before)
        internal
        view
        returns (uint256 setBitIndex)
    {
        uint256 bucket;
        uint256 bucketBits;
        /// @solidity memory-safe-assembly
        assembly {
            setBitIndex := not(0)
            bucket := shr(8, before)
            mstore(0x00, bucket)
            mstore(0x20, bitmap.slot)
            let offset := xor(0xff, and(0xff, before)) // `256 - (255 & before) - 1`.
            bucketBits := shr(offset, shl(offset, sload(keccak256(0x00, 0x40))))
            if iszero(bucketBits) {
                for {} bucket {} {
                    bucket := sub(bucket, 1)
                    mstore(0x00, bucket)
                    bucketBits := sload(keccak256(0x00, 0x40))
                    if bucketBits { break }
                }
            }
        }
        if (bucketBits != 0) {
            setBitIndex = (bucket << 8) | LibBit.fls(bucketBits);
            /// @solidity memory-safe-assembly
            assembly {
                setBitIndex := or(setBitIndex, sub(0, gt(setBitIndex, before)))
            }
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/Math.sol)

pragma solidity ^0.8.0;

/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library Math {
    enum Rounding {
        Down, // Toward negative infinity
        Up, // Toward infinity
        Zero // Toward zero
    }

    /**
     * @dev Returns the largest of two numbers.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a > b ? a : b;
    }

    /**
     * @dev Returns the smallest of two numbers.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two numbers. The result is rounded towards
     * zero.
     */
    function average(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b) / 2 can overflow.
        return (a & b) + (a ^ b) / 2;
    }

    /**
     * @dev Returns the ceiling of the division of two numbers.
     *
     * This differs from standard division with `/` in that it rounds up instead
     * of rounding down.
     */
    function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b - 1) / b can overflow on addition, so we distribute.
        return a == 0 ? 0 : (a - 1) / b + 1;
    }

    /**
     * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
     * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
     * with further edits by Uniswap Labs also under MIT license.
     */
    function mulDiv(
        uint256 x,
        uint256 y,
        uint256 denominator
    ) internal pure returns (uint256 result) {
        unchecked {
            // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
            // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
            // variables such that product = prod1 * 2^256 + prod0.
            uint256 prod0; // Least significant 256 bits of the product
            uint256 prod1; // Most significant 256 bits of the product
            assembly {
                let mm := mulmod(x, y, not(0))
                prod0 := mul(x, y)
                prod1 := sub(sub(mm, prod0), lt(mm, prod0))
            }

            // Handle non-overflow cases, 256 by 256 division.
            if (prod1 == 0) {
                return prod0 / denominator;
            }

            // Make sure the result is less than 2^256. Also prevents denominator == 0.
            require(denominator > prod1);

            ///////////////////////////////////////////////
            // 512 by 256 division.
            ///////////////////////////////////////////////

            // Make division exact by subtracting the remainder from [prod1 prod0].
            uint256 remainder;
            assembly {
                // Compute remainder using mulmod.
                remainder := mulmod(x, y, denominator)

                // Subtract 256 bit number from 512 bit number.
                prod1 := sub(prod1, gt(remainder, prod0))
                prod0 := sub(prod0, remainder)
            }

            // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
            // See https://cs.stackexchange.com/q/138556/92363.

            // Does not overflow because the denominator cannot be zero at this stage in the function.
            uint256 twos = denominator & (~denominator + 1);
            assembly {
                // Divide denominator by twos.
                denominator := div(denominator, twos)

                // Divide [prod1 prod0] by twos.
                prod0 := div(prod0, twos)

                // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                twos := add(div(sub(0, twos), twos), 1)
            }

            // Shift in bits from prod1 into prod0.
            prod0 |= prod1 * twos;

            // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
            // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
            // four bits. That is, denominator * inv = 1 mod 2^4.
            uint256 inverse = (3 * denominator) ^ 2;

            // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
            // in modular arithmetic, doubling the correct bits in each step.
            inverse *= 2 - denominator * inverse; // inverse mod 2^8
            inverse *= 2 - denominator * inverse; // inverse mod 2^16
            inverse *= 2 - denominator * inverse; // inverse mod 2^32
            inverse *= 2 - denominator * inverse; // inverse mod 2^64
            inverse *= 2 - denominator * inverse; // inverse mod 2^128
            inverse *= 2 - denominator * inverse; // inverse mod 2^256

            // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
            // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
            // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
            // is no longer required.
            result = prod0 * inverse;
            return result;
        }
    }

    /**
     * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
     */
    function mulDiv(
        uint256 x,
        uint256 y,
        uint256 denominator,
        Rounding rounding
    ) internal pure returns (uint256) {
        uint256 result = mulDiv(x, y, denominator);
        if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
            result += 1;
        }
        return result;
    }

    /**
     * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
     *
     * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
     */
    function sqrt(uint256 a) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
        //
        // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
        // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
        //
        // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
        // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
        // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
        //
        // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
        uint256 result = 1 << (log2(a) >> 1);

        // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
        // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
        // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
        // into the expected uint128 result.
        unchecked {
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            return min(result, a / result);
        }
    }

    /**
     * @notice Calculates sqrt(a), following the selected rounding direction.
     */
    function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = sqrt(a);
            return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 2, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 128;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 64;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 32;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 16;
            }
            if (value >> 8 > 0) {
                value >>= 8;
                result += 8;
            }
            if (value >> 4 > 0) {
                value >>= 4;
                result += 4;
            }
            if (value >> 2 > 0) {
                value >>= 2;
                result += 2;
            }
            if (value >> 1 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log2(value);
            return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 10, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >= 10**64) {
                value /= 10**64;
                result += 64;
            }
            if (value >= 10**32) {
                value /= 10**32;
                result += 32;
            }
            if (value >= 10**16) {
                value /= 10**16;
                result += 16;
            }
            if (value >= 10**8) {
                value /= 10**8;
                result += 8;
            }
            if (value >= 10**4) {
                value /= 10**4;
                result += 4;
            }
            if (value >= 10**2) {
                value /= 10**2;
                result += 2;
            }
            if (value >= 10**1) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log10(value);
            return result + (rounding == Rounding.Up && 10**result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 256, rounded down, of a positive value.
     * Returns 0 if given 0.
     *
     * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
     */
    function log256(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 16;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 8;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 4;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 2;
            }
            if (value >> 8 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log256(value);
            return result + (rounding == Rounding.Up && 1 << (result * 8) < value ? 1 : 0);
        }
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;

import "./ERC721Psi.sol";
import "@openzeppelin/contracts/access/Ownable.sol";

contract MetaDollsNFT is ERC721Psi, Ownable {
    constructor()
        ERC721Psi ("MetaDolls NFT", "METADOLLS") {
    }

    function _baseURI() internal pure override returns (string memory) {
        return "ipfs://bafybeigt44of3nq6ycdzaurs3gqn3b6x7y7gnz6z5elmykfddjaanln3ke/";
    }

    function _startTokenId() internal view override returns (uint256) {
        return 1;
    }

    function mint(uint256 quantity, address wallet) external onlyOwner {
        // _safeMint's second argument now takes in a quantity, not a tokenId. (same as ERC721A)
        _safeMint(wallet, quantity);
    }

    /**********************************************************
    *
    *  ROYALTY
    *
    **********************************************************/
    function royaltyInfo(uint, uint _salePrice) external view returns (address receiver, uint256 royaltyAmount) {
        return (0x6E9cc0Ac20a79501A8d9950cebc160fF6840E026, (_salePrice * 777) / 10000);
    }

    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC721Psi) returns (bool) {
        return (interfaceId == 0x2a55205a ||
        super.supportsInterface(interfaceId));
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "../utils/Context.sol";

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

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

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

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

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

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

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

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

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/Strings.sol)

pragma solidity ^0.8.0;

import "./math/Math.sol";

/**
 * @dev String operations.
 */
library Strings {
    bytes16 private constant _SYMBOLS = "0123456789abcdef";
    uint8 private constant _ADDRESS_LENGTH = 20;

    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        unchecked {
            uint256 length = Math.log10(value) + 1;
            string memory buffer = new string(length);
            uint256 ptr;
            /// @solidity memory-safe-assembly
            assembly {
                ptr := add(buffer, add(32, length))
            }
            while (true) {
                ptr--;
                /// @solidity memory-safe-assembly
                assembly {
                    mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
                }
                value /= 10;
                if (value == 0) break;
            }
            return buffer;
        }
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        unchecked {
            return toHexString(value, Math.log256(value) + 1);
        }
    }

    /**
     * @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] = _SYMBOLS[value & 0xf];
            value >>= 4;
        }
        require(value == 0, "Strings: hex length insufficient");
        return string(buffer);
    }

    /**
     * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
     */
    function toHexString(address addr) internal pure returns (string memory) {
        return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
    }
}

{
  "compilationTarget": {
    "contracts/MetaDollsNFT-psi.sol": "MetaDollsNFT"
  },
  "evmVersion": "london",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": false,
    "runs": 200
  },
  "remappings": []
}