Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./IERC721.sol";
import "./IERC721Receiver.sol";
import "./extensions/IERC721Metadata.sol";
import "../../utils/Address.sol";
import "../../utils/Context.sol";
import "../../utils/Strings.sol";
import "../../utils/introspection/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 {
require(operator != _msgSender(), "ERC721: approve to caller");
_operatorApprovals[_msgSender()][operator] = approved;
emit ApprovalForAll(_msgSender(), operator, approved);
}
/**
* @dev See {IERC721-isApprovedForAll}.
*/
function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
return _operatorApprovals[owner][operator];
}
/**
* @dev See {IERC721-transferFrom}.
*/
function transferFrom(
address from,
address to,
uint256 tokenId
) public virtual override {
//solhint-disable-next-line max-line-length
require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
_transfer(from, to, tokenId);
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId
) public virtual override {
safeTransferFrom(from, to, tokenId, "");
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId,
bytes memory _data
) public virtual override {
require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
_safeTransfer(from, to, tokenId, _data);
}
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
* are aware of the ERC721 protocol to prevent tokens from being forever locked.
*
* `_data` is additional data, it has no specified format and it is sent in call to `to`.
*
* This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
* implement alternative mechanisms to perform token transfer, such as signature-based.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function _safeTransfer(
address from,
address to,
uint256 tokenId,
bytes memory _data
) internal virtual {
_transfer(from, to, tokenId);
require(_checkOnERC721Received(from, to, tokenId, _data), "ERC721: transfer to non ERC721Receiver implementer");
}
/**
* @dev Returns whether `tokenId` exists.
*
* Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
*
* Tokens start existing when they are minted (`_mint`),
* and stop existing when they are burned (`_burn`).
*/
function _exists(uint256 tokenId) internal view virtual returns (bool) {
return _owners[tokenId] != address(0);
}
/**
* @dev Returns whether `spender` is allowed to manage `tokenId`.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {
require(_exists(tokenId), "ERC721: operator query for nonexistent token");
address owner = ERC721.ownerOf(tokenId);
return (spender == owner || getApproved(tokenId) == spender || isApprovedForAll(owner, spender));
}
/**
* @dev Safely mints `tokenId` and transfers it to `to`.
*
* Requirements:
*
* - `tokenId` must not exist.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function _safeMint(address to, uint256 tokenId) internal virtual {
_safeMint(to, tokenId, "");
}
/**
* @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
* forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
*/
function _safeMint(
address to,
uint256 tokenId,
bytes memory _data
) internal virtual {
_mint(to, tokenId);
require(
_checkOnERC721Received(address(0), to, tokenId, _data),
"ERC721: transfer to non ERC721Receiver implementer"
);
}
/**
* @dev Mints `tokenId` and transfers it to `to`.
*
* WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
*
* Requirements:
*
* - `tokenId` must not exist.
* - `to` cannot be the zero address.
*
* Emits a {Transfer} event.
*/
function _mint(address to, uint256 tokenId) internal virtual {
require(to != address(0), "ERC721: mint to the zero address");
require(!_exists(tokenId), "ERC721: token already minted");
_beforeTokenTransfer(address(0), to, tokenId);
_balances[to] += 1;
_owners[tokenId] = to;
emit Transfer(address(0), to, tokenId);
}
/**
* @dev Destroys `tokenId`.
* The approval is cleared when the token is burned.
*
* Requirements:
*
* - `tokenId` must exist.
*
* Emits a {Transfer} event.
*/
function _burn(uint256 tokenId) internal virtual {
address owner = ERC721.ownerOf(tokenId);
_beforeTokenTransfer(owner, address(0), tokenId);
// Clear approvals
_approve(address(0), tokenId);
_balances[owner] -= 1;
delete _owners[tokenId];
emit Transfer(owner, address(0), tokenId);
}
/**
* @dev Transfers `tokenId` from `from` to `to`.
* As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
*
* Emits a {Transfer} event.
*/
function _transfer(
address from,
address to,
uint256 tokenId
) internal virtual {
require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer of token that is not own");
require(to != address(0), "ERC721: transfer to the zero address");
_beforeTokenTransfer(from, to, tokenId);
// Clear approvals from the previous owner
_approve(address(0), tokenId);
_balances[from] -= 1;
_balances[to] += 1;
_owners[tokenId] = to;
emit Transfer(from, to, tokenId);
}
/**
* @dev Approve `to` to operate on `tokenId`
*
* Emits a {Approval} event.
*/
function _approve(address to, uint256 tokenId) internal virtual {
_tokenApprovals[tokenId] = to;
emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
}
/**
* @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
* The call is not executed if the target address is not a contract.
*
* @param from address representing the previous owner of the given token ID
* @param to target address that will receive the tokens
* @param tokenId uint256 ID of the token to be transferred
* @param _data bytes optional data to send along with the call
* @return bool whether the call correctly returned the expected magic value
*/
function _checkOnERC721Received(
address from,
address to,
uint256 tokenId,
bytes memory _data
) private returns (bool) {
if (to.isContract()) {
try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, _data) returns (bytes4 retval) {
return retval == IERC721Receiver(to).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 "../../utils/introspection/IERC165.sol";
/**
* @dev Required interface of an ERC721 compliant contract.
*/
interface IERC721 is IERC165 {
/**
* @dev Emitted when `tokenId` token is transferred from `from` to `to`.
*/
event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
*/
event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
*/
event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
/**
* @dev Returns the number of tokens in ``owner``'s account.
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @dev Returns the owner of the `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function ownerOf(uint256 tokenId) external view returns (address owner);
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
* are aware of the ERC721 protocol to prevent tokens from being forever locked.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId
) external;
/**
* @dev Transfers `tokenId` token from `from` to `to`.
*
* WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
*
* Emits a {Transfer} event.
*/
function transferFrom(
address from,
address to,
uint256 tokenId
) external;
/**
* @dev Gives permission to `to` to transfer `tokenId` token to another account.
* The approval is cleared when the token is transferred.
*
* Only a single account can be approved at a time, so approving the zero address clears previous approvals.
*
* Requirements:
*
* - The caller must own the token or be an approved operator.
* - `tokenId` must exist.
*
* Emits an {Approval} event.
*/
function approve(address to, uint256 tokenId) external;
/**
* @dev Returns the account approved for `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function getApproved(uint256 tokenId) external view returns (address operator);
/**
* @dev Approve or remove `operator` as an operator for the caller.
* Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
*
* Requirements:
*
* - The `operator` cannot be the caller.
*
* Emits an {ApprovalForAll} event.
*/
function setApprovalForAll(address operator, bool _approved) external;
/**
* @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
*
* See {setApprovalForAll}
*/
function isApprovedForAll(address owner, address operator) external view returns (bool);
/**
* @dev Safely transfers `tokenId` token from `from` to `to`.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId,
bytes calldata data
) external;
}
// 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 ^0.8.0;
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;
/**
* @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);
}
function _verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) private 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;
/**
* @title Counters
* @author Matt Condon (@shrugs)
* @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
* of elements in a mapping, issuing ERC721 ids, or counting request ids.
*
* Include with `using Counters for Counters.Counter;`
*/
library Counters {
struct Counter {
// This variable should never be directly accessed by users of the library: interactions must be restricted to
// the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
// this feature: see https://github.com/ethereum/solidity/issues/4637
uint256 _value; // default: 0
}
function current(Counter storage counter) internal view returns (uint256) {
return counter._value;
}
function increment(Counter storage counter) internal {
unchecked {
counter._value += 1;
}
}
function decrement(Counter storage counter) internal {
uint256 value = counter._value;
require(value > 0, "Counter: decrement overflow");
unchecked {
counter._value = value - 1;
}
}
function reset(Counter storage counter) internal {
counter._value = 0;
}
}
// 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);
}
}
// 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;
/**
* @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
/// @title Base64
/// @author Brecht Devos - <[email protected]>
/// @notice Provides a function for encoding some bytes in base64
library Base64 {
string internal constant TABLE = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
function encode(bytes memory data) internal pure returns (string memory) {
if (data.length == 0) return '';
// load the table into memory
string memory table = TABLE;
// multiply by 4/3 rounded up
uint256 encodedLen = 4 * ((data.length + 2) / 3);
// add some extra buffer at the end required for the writing
string memory result = new string(encodedLen + 32);
assembly {
// set the actual output length
mstore(result, encodedLen)
// prepare the lookup table
let tablePtr := add(table, 1)
// input ptr
let dataPtr := data
let endPtr := add(dataPtr, mload(data))
// result ptr, jump over length
let resultPtr := add(result, 32)
// run over the input, 3 bytes at a time
for {} lt(dataPtr, endPtr) {}
{
dataPtr := add(dataPtr, 3)
// read 3 bytes
let input := mload(dataPtr)
// write 4 characters
mstore(resultPtr, shl(248, mload(add(tablePtr, and(shr(18, input), 0x3F)))))
resultPtr := add(resultPtr, 1)
mstore(resultPtr, shl(248, mload(add(tablePtr, and(shr(12, input), 0x3F)))))
resultPtr := add(resultPtr, 1)
mstore(resultPtr, shl(248, mload(add(tablePtr, and(shr( 6, input), 0x3F)))))
resultPtr := add(resultPtr, 1)
mstore(resultPtr, shl(248, mload(add(tablePtr, and( input, 0x3F)))))
resultPtr := add(resultPtr, 1)
}
// padding with '='
switch mod(mload(data), 3)
case 1 { mstore(sub(resultPtr, 2), shl(240, 0x3d3d)) }
case 2 { mstore(sub(resultPtr, 1), shl(248, 0x3d)) }
}
return result;
}
}
// SPDX-License-Identifier: MIT
/*
( (
( )\ ( ( ( ( )\ (
)((_) ))\ )( ( )\ ) )((_) ( )\ ) (
((_)_ /((_|()\ )\ )(()/( ((_)_ )\(()/( )\
| _ |_))( ((_)_(_/( )(_)) | _ ) ((_))(_)|(_)
| _ \ || | '_| ' \)) || | | _ \/ _ \ || (_-<
|___/\_,_|_| |_||_| \_, | |___/\___/\_, /__/
|__/ |__/
*/
pragma solidity ^0.8.7;
import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@openzeppelin/contracts/utils/Counters.sol";
import "./MetaDataGenerator.sol";
contract BurnNFT is ERC721 {
using Counters for Counters.Counter;
Counters.Counter private _tokenIds;
event NewToken(address _minter, uint256 _tokenId, uint256 _baseFee);
uint public limit;
uint256 public price;
address public beneficiary;
uint256 public minBaseFee = 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff;
uint256 public maxBaseFee = 1;
mapping(uint256 => uint256) public tokenBaseFee;
constructor(uint _limit, uint256 _price, address _beneficiary) ERC721("BurnyBoy", "BURN") {
limit = _limit;
price = _price;
beneficiary = _beneficiary;
}
function mint() public payable returns (uint256) {
require(msg.value >= price, "price too low");
_tokenIds.increment();
uint256 newItemId = _tokenIds.current();
require(newItemId <= limit, "at limit");
_safeMint(msg.sender, newItemId);
uint256 baseFee = block.basefee;
tokenBaseFee[newItemId] = baseFee;
if(baseFee > maxBaseFee) {
maxBaseFee = baseFee;
}
if(baseFee < minBaseFee) {
minBaseFee = baseFee;
}
emit NewToken(msg.sender, newItemId, baseFee);
return newItemId;
}
function withdrawFunds() public {
require(msg.sender == beneficiary, 'only beneficiary');
uint amount = address(this).balance;
(bool success,) = beneficiary.call{value: amount}("");
require(success, "Failed");
}
function totalSupply() public view returns (uint256) {
return _tokenIds.current();
}
function tokenURI(uint256 id) public view override returns (string memory) {
require(_exists(id), "not exist");
return MetaDataGenerator.tokenURI(
MetaDataGenerator.MetaDataParams({
tokenId: id,
tokenBaseFee:
tokenBaseFee[id],
owner: ownerOf(id),
minBaseFee: minBaseFee,
maxBaseFee: maxBaseFee,
fireHeight: 0,
readableBaseFee: '',
ownerOrBurniest: ''
}));
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.7;
library HexStrings {
bytes16 internal constant ALPHABET = '0123456789abcdef';
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] = ALPHABET[value & 0xf];
value >>= 4;
}
return string(buffer);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.7;
import 'base64-sol/base64.sol';
import "@openzeppelin/contracts/utils/Strings.sol";
import './HexStrings.sol';
/// @title NFTSVG
/// @notice Provides a function for generating an SVG associated with a Uniswap NFT
library MetaDataGenerator {
using Strings for uint256;
using HexStrings for uint160;
struct MetaDataParams {
uint256 tokenId;
uint256 tokenBaseFee;
address owner;
uint256 minBaseFee;
uint256 maxBaseFee;
uint fireHeight;
string readableBaseFee;
string ownerOrBurniest;
}
string internal constant svgStart = '<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 300 300"><defs><linearGradient id="linear-gradient" x1="150" x2="150" y2="300" gradientUnits="userSpaceOnUse"><stop offset="0" stop-color="#00bdd0"/><stop offset="1" stop-color="#008ad0"/></linearGradient><linearGradient id="linear-gradient-2" x1="30.7" y1="-8.2" x2="30.7" y2="141.5" gradientUnits="userSpaceOnUse"><stop offset="0" stop-color="#f16d76"/><stop offset="1" stop-color="#ffa358"/></linearGradient><linearGradient id="linear-gradient-3" x1="34.5" y1="29.9" x2="34.5" y2="144.9" gradientUnits="userSpaceOnUse"><stop offset="0" stop-color="#ffbd58"/><stop offset="1" stop-color="#f6ec47"/></linearGradient><linearGradient id="linear-gradient-4" x1="31.9" y1="2.5" x2="31.9" y2="146.3" xlink:href="#linear-gradient-2"/><linearGradient id="linear-gradient-5" x1="67.8" y1="27.9" x2="67.8" y2="74.5" xlink:href="#linear-gradient-2"/><linearGradient id="linear-gradient-6" x1="36.5" y1="-15.1" x2="36.5" y2="52.8" xlink:href="#linear-gradient-2"/><linearGradient id="linear-gradient-7" x1="33.6" y1="22.5" x2="33.6" y2="148.5" xlink:href="#linear-gradient-3"/><linearGradient id="linear-gradient-8" x1="23.1" y1="-8.3" x2="23.1" y2="155.9" xlink:href="#linear-gradient-2"/><linearGradient id="linear-gradient-9" x1="64.9" y1="6.7" x2="64.9" y2="100" xlink:href="#linear-gradient-2"/><linearGradient id="linear-gradient-10" x1="48.4" y1="-45.8" x2="48.4" y2="80.7" xlink:href="#linear-gradient-2"/><linearGradient id="linear-gradient-11" x1="25.6" y1="8.2" x2="25.6" y2="149.8" xlink:href="#linear-gradient-3"/><linearGradient id="linear-gradient-12" x1="150" y1="300" x2="150" y2="139.8" xlink:href="#linear-gradient-3"/><linearGradient id="linear-gradient-13" x1="96" y1="202.4" x2="150" y2="202.4" gradientUnits="userSpaceOnUse"><stop offset="0" stop-color="#574581"/><stop offset="1" stop-color="#4c235b"/></linearGradient><linearGradient id="linear-gradient-14" x1="150" y1="202.4" x2="204" y2="202.4" gradientUnits="userSpaceOnUse"><stop offset="0" stop-color="#ea496a"/><stop offset="1" stop-color="#ea6b60"/></linearGradient><linearGradient id="linear-gradient-15" x1="150" y1="153.7" x2="204" y2="153.7" xlink:href="#linear-gradient-14"/><linearGradient id="linear-gradient-16" x1="204" y1="105" x2="150" y2="105" xlink:href="#linear-gradient"/><linearGradient id="linear-gradient-17" x1="96" y1="105" x2="150" y2="105" xlink:href="#linear-gradient-14"/><linearGradient id="linear-gradient-18" x1="96" y1="153.7" x2="150" y2="153.7" xlink:href="#linear-gradient-13"/><linearGradient id="linear-gradient-19" x1="149.1" y1="24" x2="149.1" y2="276" xlink:href="#linear-gradient-13"/><clipPath id="clip-path"><path class="cls-1" d="M0-42.3h300v188.6H0z"/></clipPath><clipPath id="clip-path-2"><path class="cls-1" d="M.4 0h300v300H.4z"/></clipPath><style>.cls-1{fill:none}.cls-2{fill:url(#linear-gradient)}.cls-4{fill:url(#linear-gradient-2)}.cls-5{fill:url(#linear-gradient-3)}.cls-14{fill:url(#linear-gradient-12)}.cls-15{opacity:.2}.cls-16{clip-path:url(#clip-path-2)}.cls-17{fill:#e75a00}.cls-18{fill:url(#linear-gradient-13)}.cls-19{fill:#fff}.cls-20{fill:url(#linear-gradient-14)}.cls-21{fill:url(#linear-gradient-15)}.cls-22{fill:url(#linear-gradient-16)}.cls-23{fill:url(#linear-gradient-17)}.cls-24{fill:url(#linear-gradient-18)}.cls-25{stroke:#fff;stroke-miterlimit:10;fill:url(#linear-gradient-19)}</style></defs><path class="cls-2" d="M0 0h300v300H0z" id="background"/><g id="fire-layer"><g id="Fire_to_move" data-name="Fire to move"><g id="Fire1"><g id="fire-001"><path class="cls-4" d="M-4.4 139.2c-.4-12.2-17.5-31.5-9.6-49s21-13 24-30c0 0 10.3 9.6 1.1 21.6 0 0 13.3-3.8 12.8-14.6s1.5-15.7-7.4-18-22.2-18.4-9.3-35.5c0 0 2.4 14.4 13.8 8.1s20.7-26 1-26.5c0 0 12.3-8.1 19.7.4s-9.4 27-3.5 31.5S52 33.1 51.5 43 35.8 61.8 41.2 66.3s19.3 1.5 19.7-3.3c.3-4.8-7.9-10.6-1-20a18.7 18.7 0 009 11.8c9.9 5.5 12.2 17.8 2.3 26.8-6.7 6.2-15-3.4-15.9 5.9-.6 5.4 21 13 19 29.1-3.7 29.7 9.3 24.5-33.1 24.5-47.6 0-45.6-1.9-45.6-1.9z"/><path class="cls-5" d="M35 145c-62.2 0-33.8-7.3-27-16.2C19.8 113.2-2.7 113.6-2.2 100s8.9-20.3 8.9-20.3-5.2 16 2.2 16.5S24 91 27.9 76c6.6-26.2.5-40.3-8.4-46.2A37.5 37.5 0 0138 39.6c6 6-4.6 17.3-4.3 26.7.7 24.6 34.8 5 31.7-5.8 0 0 9.5 14.8-2.9 17-22.4 4.2-21.4 20.6-13 26s6 16.3 13.6 24.6c10 11 26 16.8-28.3 16.8z"/></g><use href="#fire-001" x="77"/><use href="#fire-001" x="154"/><use href="#fire-001" x="231"/></g><path class="cls-14" d="M0 139.8h300V300H0z"/></g></g><g class="cls-15" id="ray"><g class="cls-16"><path id="ray1" class="cls-17" d="M153.4 383q8.5-.1 16.9-.8L153.4 211z"/></g>';
string internal constant svgMiddle = '</g><g id="Ether"><path class="cls-18" d="M150 197.4v44.5l-54-79 54 34.5z"/><path class="cls-19" d="M150 242.3a.4.4 0 01-.3-.2l-54-78.9a.4.4 0 01.5-.5l54 34.3a.4.4 0 01.2.4v44.5a.4.4 0 01-.3.4.4.4 0 01-.1 0zm-52.6-78l52.2 76.3v-43z"/><path class="cls-20" d="M204 163l-54 78.9v-44.5l54-34.4z"/><path class="cls-19" d="M150 242.3a.4.4 0 01-.1 0 .4.4 0 01-.3-.4v-44.5a.4.4 0 01.2-.4l54-34.3a.4.4 0 01.5.5l-54 78.9a.4.4 0 01-.3.2zm.4-44.7v43l52.2-76.2z"/><path class="cls-21" d="M204 151.9l-54-30.7v65l54-34.3z"/><path class="cls-19" d="M150 186.7a.4.4 0 01-.4-.4v-65.1a.4.4 0 01.6-.4l54 30.7a.4.4 0 010 .7l-54 34.4a.4.4 0 01-.2 0zm.4-64.8v63.6l52.8-33.6z"/><g><path class="cls-22" d="M204 151.9L150 58v63l54 30.8z"/><path class="cls-19" d="M204 152.3a.4.4 0 01-.2 0l-54-30.8a.4.4 0 01-.2-.3v-63a.4.4 0 01.7-.3l54 93.8a.4.4 0 01-.3.6zM150.4 121l52.5 29.8-52.5-91.2z"/></g><g><path class="cls-23" d="M150 58.1v63L96 152 150 58z"/><path class="cls-19" d="M96 152.3a.4.4 0 01-.3-.6l54-93.8a.4.4 0 01.7.2v63a.4.4 0 01-.2.4l-54 30.7a.4.4 0 01-.2 0zm53.6-92.7l-52.5 91.2 52.5-29.8z"/></g><g><path class="cls-24" d="M150 121.2v65L96 152l54-30.7z"/><path class="cls-19" d="M150 186.7a.4.4 0 01-.2 0l-54-34.5a.4.4 0 010-.7l54-30.7a.4.4 0 01.6.4v65a.4.4 0 01-.4.5zm-53.2-34.8l52.8 33.6V122z"/></g><g><path class="cls-19" d="M203.8 162.7L150 196.9l-53.8-34.2a.4.4 0 00-.5.5l54 78.9a.4.4 0 00.2.1.4.4 0 00.2 0 .4.4 0 00.2 0v-.1l54-78.9a.4.4 0 00-.5-.5zm-54.2 34.9v43l-52.2-76.2zm.8 43v-43l52.2-33.2z"/><path class="cls-19" d="M95.6 151.9a.4.4 0 00.1.2v.1l54 34.4h.1a.4.4 0 00.4 0l54-34.4h.1a.4.4 0 000-.2.4.4 0 000-.1h.1a.4.4 0 000-.2l-54-93.8a.4.4 0 00-.1 0 .3.3 0 00-.1-.1.2.2 0 00-.1 0 .4.4 0 00-.1 0h-.1a.3.3 0 00-.1 0 .3.3 0 00-.1.1l-54 93.8a.4.4 0 000 .2c-.1 0 0 0 0 0zm54-30v63.6L96.8 152zm.8 63.6V122l52.8 30zm0-64.5V59.6l52.5 91.2zm-.8-61.4V121l-52.5 29.8z"/></g></g><g id="Ring"><g id="rotatethis"><path class="cls-25" d="M149 24a126 126 0 10126 126A126 126 0 00149 24zm0 225.3a99.3 99.3 0 1199.4-99.3 99.3 99.3 0 01-99.3 99.3z"/><path id="textcircle" class="cls-1" d="M32 150a118 118 0 10236 0 118 118 0 10-236 0"><animateTransform attributeName="transform" begin="0s" dur="50s" type="rotate" from="0 150 150" to="360 150 150" repeatCount="indefinite"/></path></g></g><defs><style>@keyframes ff{0%,49.9%,to{transform:translate(0,0) scale(1,1)}50%,99.9%{transform:translate(300px,0) scale(-1,1)}}#Fire1{animation:ff 300ms linear infinite normal forwards}text{font-size:16px;font-family:Helvetica,sans-serif;font-weight:900;fill:#fff;letter-spacing:1px}#Ether,#Ring,#background{filter:hue-rotate(';
function generateConfigString(MetaDataParams memory params) internal pure returns (string memory) {
if(params.tokenBaseFee < 10000000) {
params.readableBaseFee = '<0.01 Gwei';
}
return string(abi.encodePacked(Strings.toString((params.tokenBaseFee + (params.tokenId * 30)) % 360),
'deg)}#Fire_to_move{transform:translate(0px,',
params.fireHeight.toString(),
'px)}</style></defs><text dy="0"><textPath xlink:href="#textcircle"> / EIP-1559 / #',
params.tokenId.toString(),
' / Basefee: ',
params.readableBaseFee,
' / ',
params.ownerOrBurniest,
unicode'🔥🔥🔥🔥🔥🔥🔥🔥',
'</textPath></text></svg>'));
}
function generateRayString() internal pure returns (string memory) {
uint16[59] memory rotations = [6,12,18,24,30,36,42,48,54,60,66,72,78,84,90,96,102,108,114,120,126,132,138,144,150,156,162,168,174,180,186,192,198,204,210,216,222,228,234,240,246,252,258,264,270,276,282,288,294,300,306,312,318,324,330,336,342,348,354];
string memory rays = '';
for (uint i=0; i<rotations.length; i++) {
rays = string(abi.encodePacked(rays,
'<use href="#ray1" transform="rotate(',
Strings.toString(rotations[i]),
' 150 150)" />'));
}
return rays;
}
function appendEmoji(string memory start, string memory emoji, uint emojiCount) internal pure returns (string memory) {
for (uint i=0; i<emojiCount; i++) {
start = string(abi.encodePacked(start, emoji));
}
return start;
}
function generateSVGofTokenById(MetaDataParams memory params) internal pure returns (string memory) {
uint height = 270;
if(params.minBaseFee == params.maxBaseFee) {
params.fireHeight = 0;
} else {
params.fireHeight = height*(uint(100)-(uint(100)*(params.tokenBaseFee-params.minBaseFee)/(params.maxBaseFee-params.minBaseFee))) / uint(100);
}
if(params.maxBaseFee == params.tokenBaseFee) {
params.ownerOrBurniest = appendEmoji(unicode'Burniest Boy ',unicode'🔥',30);
} else if(params.minBaseFee == params.tokenBaseFee) {
params.ownerOrBurniest = appendEmoji(unicode'Ice cold ',unicode'🧊',30);
} else if((params.tokenBaseFee / uint(1_000_000_000)) == 69) {
params.ownerOrBurniest = appendEmoji(unicode'Nice. ',unicode'♋',30);
} else if((params.tokenBaseFee / uint(1_000_000_000)) == 420) {
params.ownerOrBurniest = appendEmoji(unicode'Nice. ',unicode'🌲',30);
} else {
params.ownerOrBurniest = (uint160(params.owner)).toHexString(20);
}
string memory svg = string(abi.encodePacked(
svgStart,
generateRayString(),
svgMiddle,
generateConfigString(params)
));
return svg;
}
function tokenURI(MetaDataParams memory params) internal pure returns (string memory) {
string memory name = string(abi.encodePacked('Burny Boy #',params.tokenId.toString()));
if(params.tokenBaseFee < uint(10_000_000)) {
params.readableBaseFee = string(abi.encodePacked(params.tokenBaseFee.toString(), ' wei'));
} else if(params.tokenBaseFee < uint(100_000_000)) {
params.readableBaseFee = string(abi.encodePacked('0.0',Strings.toString(params.tokenBaseFee/uint(10_000_000)), ' Gwei'));
} else if(params.tokenBaseFee < uint(10_000_000_000)) {
params.readableBaseFee = string(abi.encodePacked(Strings.toString(params.tokenBaseFee/uint(1_000_000_000)),'.',Strings.toString((params.tokenBaseFee/uint(10_000_000)) % uint(100)), ' Gwei'));
} else {
params.readableBaseFee = string(abi.encodePacked(Strings.toString(params.tokenBaseFee/uint(1_000_000_000)), ' Gwei'));
}
string memory description = string(abi.encodePacked('When this burny boy was minted, the basefee was ',params.readableBaseFee));
string memory image = Base64.encode(bytes(generateSVGofTokenById(params)));
return
string(
abi.encodePacked(
'data:application/json;base64,',
Base64.encode(
bytes(
abi.encodePacked(
'{"name":"',
name,
'", "description":"',
description,
'", "external_url":"https://burnyboys.com/token/',
params.tokenId.toString(),
'", "attributes": [{"trait_type": "Base fee per gas (wei)", "value": ',
Strings.toString(params.tokenBaseFee),
'}], "owner":"',
(uint160(params.owner)).toHexString(20),
'", "image": "',
'data:image/svg+xml;base64,',
image,
'"}'
)
)
)
)
);
}
}