Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
assembly {
size := extcodesize(account)
}
return size > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value
) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
(bool success, bytes memory returndata) = target.call{value: value}(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(
address target,
bytes memory data,
string memory errorMessage
) internal view returns (bytes memory) {
require(isContract(target), "Address: static call to non-contract");
(bool success, bytes memory returndata) = target.staticcall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
require(isContract(target), "Address: delegate call to non-contract");
(bool success, bytes memory returndata) = target.delegatecall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason using the provided one.
*
* _Available since v4.3._
*/
function verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) internal pure returns (bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./IERC165.sol";
/**
* @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;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./IERC721.sol";
import "./IERC721Receiver.sol";
import "./IERC721Metadata.sol";
import "./Address.sol";
import "./Context.sol";
import "./Strings.sol";
import "./ERC165.sol";
/**
* @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 {
_setApprovalForAll(_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 Approve `operator` to operate on all of `owner` tokens
*
* Emits a {ApprovalForAll} event.
*/
function _setApprovalForAll(
address owner,
address operator,
bool approved
) internal virtual {
require(owner != operator, "ERC721: approve to caller");
_operatorApprovals[owner][operator] = approved;
emit ApprovalForAll(owner, operator, approved);
}
/**
* @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 {}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./ERC721.sol";
import "./IERC721Enumerable.sol";
/**
* @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();
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
* @dev Fully On-Chain File Access Interface -- Single file per token variant
* Interface for contracts which expose a single file for each of their tokens.
* Originally created for the NonagonCup.
*/
interface HasFile {
/**
* @dev Each file must have a filename including the file extension, for example: "my-file-1.stl"
* If the contract is an NFT where the object of the NFT is the exposed files then the filenames
* within the contract must be unique and must include the tokenId that they belong to.
*/
function getFilename(uint256 tokenId) external view returns(string memory filename);
/**
* @dev Single call to get the full file contents.
* NB: This may not work in all conditions due to gas limits, it is instead
* recommended to call getFileChunksTotal and iterate calls to getFileChunk.
*/
function getFullFile(uint256 tokenId) external view returns(bytes memory fileContents);
/**
* @dev Each file has zero or more fileChunks.
*/
function getFileChunksTotal(uint256 tokenId) external view returns(uint256 count);
/**
* @dev Use repeated calls to getFileChunk to get the binary data for the file.
* -- Size of returned data for each fileChunk must be no more than 1024 bytes.
* -- First fileChunk should be the file header, if the file format has one.
*/
function getFileChunk(uint256 tokenId, uint256 index) external view returns(bytes memory data);
}
// SPDX-License-Identifier: MIT
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);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./IERC165.sol";
/**
* @dev Required interface of an ERC721 compliant contract.
*/
interface IERC721 is IERC165 {
/**
* @dev Emitted when `tokenId` token is transferred from `from` to `to`.
*/
event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
*/
event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
*/
event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
/**
* @dev Returns the number of tokens in ``owner``'s account.
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @dev Returns the owner of the `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function ownerOf(uint256 tokenId) external view returns (address owner);
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
* are aware of the ERC721 protocol to prevent tokens from being forever locked.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId
) external;
/**
* @dev Transfers `tokenId` token from `from` to `to`.
*
* WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
*
* Emits a {Transfer} event.
*/
function transferFrom(
address from,
address to,
uint256 tokenId
) external;
/**
* @dev Gives permission to `to` to transfer `tokenId` token to another account.
* The approval is cleared when the token is transferred.
*
* Only a single account can be approved at a time, so approving the zero address clears previous approvals.
*
* Requirements:
*
* - The caller must own the token or be an approved operator.
* - `tokenId` must exist.
*
* Emits an {Approval} event.
*/
function approve(address to, uint256 tokenId) external;
/**
* @dev Returns the account approved for `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function getApproved(uint256 tokenId) external view returns (address operator);
/**
* @dev Approve or remove `operator` as an operator for the caller.
* Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
*
* Requirements:
*
* - The `operator` cannot be the caller.
*
* Emits an {ApprovalForAll} event.
*/
function setApprovalForAll(address operator, bool _approved) external;
/**
* @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
*
* See {setApprovalForAll}
*/
function isApprovedForAll(address owner, address operator) external view returns (bool);
/**
* @dev Safely transfers `tokenId` token from `from` to `to`.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId,
bytes calldata data
) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./IERC721.sol";
/**
* @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);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./IERC721.sol";
/**
* @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);
}
// SPDX-License-Identifier: MIT
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);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.4.22 <0.9.0;
contract Migrations {
address public owner = msg.sender;
uint public last_completed_migration;
modifier restricted() {
require(
msg.sender == owner,
"This function is restricted to the contract's owner"
);
_;
}
function setCompleted(uint completed) public restricted {
last_completed_migration = completed;
}
}
/**
* NonagonCup
* An ERC721 NFT consisting of on-chain STL files describing unique nine-sided cups
* by Jacob Robbins
*/
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./ERC721Enumerable.sol";
import "./Ownable.sol";
import "./ReentrancyGuard.sol";
import "./HasFile.sol";
contract NonagonCup is ERC721Enumerable, ReentrancyGuard, Ownable, HasFile {
using Strings for uint256;
bytes32 private constant header = hex"53544C42204154462031302E31302E302E3133393120434F4C4F523DA0A0A0FF";
uint32 private constant facetCount = 68;
uint8 private constant heightProgVal = 254;
uint8 private constant thickProgVal = 253;
// Era 1
bytes4 private constant thick0 = hex'000080C0';
bytes private constant verts0 = hex'F095DBC123E09A40000000000B538FC1AECEAA41B519C1C121F95EC1CB8518C1B786D1C1CB851841B519C141F095DB410B538F41000020A721F9DE41DF449AC1C5D9B741975AECC1C7B3A6409AD8CFC1000070C16F2B24C1B786E1C16F2B2441DF449A410000F041975AEC419AD8CF41';
bytes private constant prog0 = hex'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';
// Era 2
bytes4 private constant thick1 = hex'0000FEC0';
bytes private constant verts1 = hex'C3131CC23C2ADC40000000008BBECBC122D0F241824009C2257C9EC1F7D158C158ED14C2F7D1584182400942C3131C428BBECB41257C1E42731EDDC178C203420E6329C29DF0EE40D5F414C20000ACC1534F6BC18CA021C2534F6B41731EDD4100002C420E632942D5F41442';
bytes private constant prog1 = hex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
// Era 3
bytes4 private constant thick2 = hex'000048C1';
bytes private constant verts2 = hex'3BE137C21FB1014100000000BD09F0C179080F4281B321C269B7BAC172717FC1C1742FC272717F4181B321423BE13742BD09F0410000A02769B73A4228B305C256561F420BD74CC2AC7910411F2234C20000D0C1C7478EC1C17443C2C7478E4128B30542000050420BD74C421F223442';
bytes private constant prog2 = hex'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';
bool private _mintApprovalRequired = true;
mapping(address => bool) private _allowedToMint;
mapping(uint256 => string) private _ownerSetURIs;
constructor() ERC721("NonagonCup", "NON") Ownable() {}
event Supported(
address indexed supported,
uint32 amount
);
event AllowedToMint(
address indexed recipient,
bool allowed
);
receive() external payable {
emit Supported(_msgSender(), uint32(msg.value));
}
function allowedToMint(address a) public view returns(bool) {
return(_allowedToMint[a]);
}
// when minting approval is required, accounts can mint when they have been added to the allowed mapping
function claim() public nonReentrant {
if (_mintApprovalRequired) {
require(_allowedToMint[_msgSender()], 'address not allowed');
}
uint256 tokenId = 1 + totalSupply();
require(tokenId < 2001);
_allowedToMint[_msgSender()] = false;
_safeMint(_msgSender(), tokenId);
}
// owner can add accounts to the allowed mapping
function updateAllowedToMint(address[] calldata toAddresses, bool isAllowed) public onlyOwner {
address curr;
for (uint256 i=0; i < toAddresses.length; i++) {
curr = toAddresses[i];
require(curr != address(0));
_allowedToMint[curr] = isAllowed;
emit AllowedToMint(curr, isAllowed);
}
}
// owner can airdop to any address
function mintFullRide(address to) public onlyOwner {
uint256 tokenId = 1 + totalSupply();
require(tokenId < 2001);
_safeMint(to, tokenId);
}
// owner can withdraw funds, partially motivated by need to carry out admin actions
function withdrawFunds(uint256 amount) public onlyOwner {
payable(owner()).transfer(amount);
}
function setMintApprovalRequired(bool val) public onlyOwner {
_mintApprovalRequired = val;
}
function _baseURI() internal pure override returns (string memory) {
return "https://nonagoncup.com/tokenId/";
}
// token owners can set their token's URI to point to an external URL
// Note that it must return JSON matching the ERC-721 Non-Fungible Token Standard, optional metadata extension
// See https://eips.ethereum.org/EIPS/eip-721
function ownerSetTokenURI(uint256 tokenId, string calldata userSuppliedURI) public {
require(_msgSender() == ownerOf(tokenId));
_ownerSetURIs[tokenId] = userSuppliedURI;
}
function tokenURI(uint256 tokenId) override public view returns (string memory) {
bytes memory userSetURI = bytes(_ownerSetURIs[tokenId]);
if (userSetURI.length != 0) {
return(_ownerSetURIs[tokenId]);
}
return(super.tokenURI(tokenId));
}
// Implementation of the HasFile interface
function getFilename(uint256 tokenId) public pure override returns(string memory filename) {
require(tokenId > 0 && tokenId < 2001, "Token ID invalid");
filename = string(abi.encodePacked("NonagonCup-", tokenId.toString(), ".stl" ));
}
function getFullFile(uint256 tokenId) public pure override returns(bytes memory fileContents) {
for (uint256 i=0; i < 10; i++) {
fileContents = bytes.concat(fileContents, getFileChunk(tokenId, i));
}
}
function getFileChunksTotal(uint256) public pure override returns(uint256 count) {
count = 10;
}
function getFileChunk(uint256 tokenId, uint256 index) public pure override returns(bytes memory data) {
require(tokenId > 0 && tokenId < 2001, "Token ID invalid");
require(index < 10, "index too large");
if (index == 0) {
// first chunk is header
// STL File Header -- https://en.wikipedia.org/wiki/STL_(file_format)
// 80 bytes -- descriptive text
// 4 bytes -- little-endian unsigned int holding the total number of triangles
bytes8 _c = hex"2020202020202020";
data = bytes.concat(header, _c, _c, _c, _c, _c, _c, bytes4(facetCount << 24));
} else {
// body chunks have 8 triangles, except for last chunk which has 4
index = (index - 1) * 8;
data = bytes.concat(_getTriangleData(tokenId, index), _getTriangleData(tokenId, index + 1),
_getTriangleData(tokenId, index + 2), _getTriangleData(tokenId, index + 3));
if (index < 64) {
data = bytes.concat(data, _getTriangleData(tokenId, index + 4), _getTriangleData(tokenId, index + 5),
_getTriangleData(tokenId, index + 6), _getTriangleData(tokenId, index + 7));
}
}
}
// STL File Triangle -- https://en.wikipedia.org/wiki/STL_(file_format)
// total size - 50 bytes
// 3 floats - normal -- NB omitted as interpreter will generate via right-hand rule
// 3 floats - vertex 1
// 3 floats - vertex 2
// 3 floats - vertex 3
// 2 bytes - attribute byte count (unused)
function _getTriangleData(uint256 tokenId, uint256 triangle_offset) private pure returns(bytes memory data) {
uint256 progOffset = triangle_offset * 9;
bytes4[9] memory triData;
bytes4 zeroFloat;
bytes2 attrData;
for (uint256 i=0; i < 9; i++) {
triData[i] = _getVertexFloatValue(tokenId, progOffset + i);
}
bytes memory firstPart = bytes.concat(zeroFloat, zeroFloat, zeroFloat, triData[0], triData[1], triData[2], triData[3], triData[4], triData[5]);
data = bytes.concat(firstPart, triData[6], triData[7], triData[8], attrData);
}
function _getVertexFloatValue(uint256 tokenId, uint256 progOffset) private pure returns(bytes4 value){
uint8 progVal;
progVal = _getProgVals(tokenId, progOffset);
// height scales with tokenId
if (progVal == heightProgVal) {
return(getHeightFloatValue(tokenId));
}
if ( tokenId < 460 ) {
if (progVal == thickProgVal) {
return(thick0);
} else {
uint256 start = progVal * 4;
value = bytes4(bytes.concat(verts0[start], verts0[start + 1], verts0[start + 2], verts0[start + 3]));
}
} else if ( tokenId < 1144) {
if (progVal == thickProgVal) {
return(thick1);
} else {
uint256 start = progVal * 4;
value = bytes4(bytes.concat(verts1[start], verts1[start + 1], verts1[start + 2], verts1[start + 3]));
}
} else {
if (progVal == thickProgVal) {
return(thick2);
} else {
uint256 start = progVal * 4;
value = bytes4(bytes.concat(verts2[start], verts2[start + 1], verts2[start + 2], verts2[start + 3]));
}
}
}
function _getProgVals(uint256 tokenId, uint256 stepNo) private pure returns(uint8 progVal) {
if (tokenId < 460) {
progVal = uint8(prog0[stepNo]);
}else if (tokenId < 1144) {
progVal = uint8(prog1[stepNo]);
}else {
progVal = uint8(prog0[stepNo]);
}
}
// returns height of cup for token in millimeters as IEEE 754 32-bit little-endian float
// this is the interior height and does not include the vertical thickness of the base
// To get the full height add the appropriate thick constant for the cup's era
function getHeightFloatValue(uint256 tokenId) public pure returns(bytes4 value) {
require(tokenId > 0 && tokenId < 2001, "Token ID invalid");
uint32 heightBase = uint32(tokenId - 1);
// determine height to nearest millimeter
uint32 mmHeight = 50 + heightBase / 8;
// determine mm height most significant bit
uint32 mmHeightMSB = 6;
if (mmHeight > 255) {
mmHeightMSB = 9;
} else if (mmHeight > 127) {
mmHeightMSB = 8;
} else if (mmHeight > 63) {
mmHeightMSB = 7;
}
// position bits into mantissa
mmHeight <<= 24 - mmHeightMSB;
// clip off implicit first bit of mantissa
uint32 mmHeightMask = 8388607;
mmHeight &= mmHeightMask;
// determine height fraction in 1/8 of a millimeter
uint32 mmHeightFraction = heightBase % 8;
// position bits into mantissa
mmHeightFraction <<= 20 - mmHeightMSB;
// normalize mantissa
uint32 exponent = 126 + mmHeightMSB;
// position bits into exponent
exponent <<= 23;
// combine parts
bytes4 b_val = bytes4(exponent | mmHeight | mmHeightFraction);
// return little-endian representation
value = bytes4(bytes.concat(b_val[3], b_val[2], b_val[1], b_val[0]));
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor() {
_transferOwnership(_msgSender());
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
* @dev Contract module that helps prevent reentrant calls to a function.
*
* Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
* available, which can be applied to functions to make sure there are no nested
* (reentrant) calls to them.
*
* Note that because there is a single `nonReentrant` guard, functions marked as
* `nonReentrant` may not call one another. This can be worked around by making
* those functions `private`, and then adding `external` `nonReentrant` entry
* points to them.
*
* TIP: If you would like to learn more about reentrancy and alternative ways
* to protect against it, check out our blog post
* https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
*/
abstract contract ReentrancyGuard {
// Booleans are more expensive than uint256 or any type that takes up a full
// word because each write operation emits an extra SLOAD to first read the
// slot's contents, replace the bits taken up by the boolean, and then write
// back. This is the compiler's defense against contract upgrades and
// pointer aliasing, and it cannot be disabled.
// The values being non-zero value makes deployment a bit more expensive,
// but in exchange the refund on every call to nonReentrant will be lower in
// amount. Since refunds are capped to a percentage of the total
// transaction's gas, it is best to keep them low in cases like this one, to
// increase the likelihood of the full refund coming into effect.
uint256 private constant _NOT_ENTERED = 1;
uint256 private constant _ENTERED = 2;
uint256 private _status;
constructor() {
_status = _NOT_ENTERED;
}
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* Calling a `nonReentrant` function from another `nonReentrant`
* function is not supported. It is possible to prevent this from happening
* by making the `nonReentrant` function external, and making it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
// On the first call to nonReentrant, _notEntered will be true
require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
// Any calls to nonReentrant after this point will fail
_status = _ENTERED;
_;
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = _NOT_ENTERED;
}
}
// SPDX-License-Identifier: MIT
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);
}
}