Contract Name:
DropspaceSale
Contract Source Code:
//SPDX-License-Identifier: Unlicense
pragma solidity ^0.8.4;
import "./IDropspaceSale.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@openzeppelin/contracts/utils/Strings.sol";
import "@openzeppelin/contracts/utils/cryptography/MerkleProof.sol";
import "erc721a/contracts/ERC721A.sol";
contract DropspaceSale is IDropspaceSale, ERC721A, Ownable {
using SafeMath for uint256;
using Strings for uint256;
uint256 MAX = 2**256 - 1;
uint256 public override mintLimit;
uint256 public override mintPrice;
uint256 public override supplyLimit;
string public override baseURI;
bool public override smartContractAllowance = false;
bool public override saleActive;
bool public override presaleActive;
bool public override whitelistSaleActive;
address payable public override withdrawalWallet;
address payable public override devWallet;
address public override ticketAddress;
bool public override whitelistBuyOnce;
uint256 devSaleShare;
uint256 ownerSaleShare;
mapping(uint256 => bool) public override usedTickets;
bytes32 public override whitelistRoot;
mapping(address => bool) public override whitelistClaimed;
constructor(
uint256 _supplyLimit,
uint256 _mintLimit,
uint256 _mintPrice,
uint256 _devSaleShare,
address payable _withdrawalWallet,
address payable _devWallet,
address _ticketAddress,
string memory _name,
string memory _ticker,
string memory _baseURI
) ERC721A(_name, _ticker) {
supplyLimit = _supplyLimit;
mintLimit = _mintLimit;
mintPrice = _mintPrice;
withdrawalWallet = _withdrawalWallet;
devWallet = _devWallet;
ticketAddress = _ticketAddress;
baseURI = _baseURI;
devSaleShare = _devSaleShare;
ownerSaleShare = uint256(10000).sub(devSaleShare);
}
modifier onlyWithdrawalWallet() {
require(address(withdrawalWallet) == _msgSender(),
"DropspaceSale: caller is not the withdrawal wallet");
_;
}
function setWhitelistBuyOnce(bool _whitelistBuyOnce) external onlyOwner override {
whitelistBuyOnce = _whitelistBuyOnce;
emit WhitelistBuyOnceChanged(whitelistBuyOnce);
}
function emergencyWithdraw() external onlyOwner override {
payable(owner()).transfer(address(this).balance);
}
function changeSupplyLimit(uint256 _supplyLimit) external onlyOwner override {
require(supplyLimit >= totalSupply(), "DropspaceSale::changeSupplyLimit: Supply Limit can't be reduced below total supply");
supplyLimit = _supplyLimit;
emit SupplyLimitChanged(_supplyLimit);
}
function setMintPrice(uint256 _mintPrice) external onlyOwner override {
mintPrice = _mintPrice;
emit MintPriceChanged(_mintPrice);
}
function setWhitelistClaimStatus(address _user, bool _status) public onlyOwner override {
_setWhitelistClaimStatus(_user, _status);
}
function _setWhitelistClaimStatus(address _user, bool _status) internal {
whitelistClaimed[_user] = _status;
emit WhitelistClaimStatusChanged(_user, _status);
}
function setWhitelistRoot(bytes32 _whitelistRoot) external onlyOwner override {
whitelistRoot = _whitelistRoot;
emit WhitelistRootChanged(whitelistRoot);
}
function setDevSaleShare(uint256 _devSaleShare) external override onlyOwner {
devSaleShare = _devSaleShare;
ownerSaleShare = uint256(10000).sub(devSaleShare);
emit DevShareSaleChanged(devSaleShare);
}
function toggleSaleActive() external onlyOwner override {
saleActive = !saleActive;
emit ToggleSaleState(saleActive);
}
function toggleWhitelistSaleActive() external onlyOwner override {
whitelistSaleActive = !whitelistSaleActive;
emit ToggleWhitelistSaleState(whitelistSaleActive);
}
function setBaseURI(string memory _baseURI) external onlyOwner override {
baseURI = _baseURI;
emit BaseURIChanged(baseURI);
}
function setSmartContractAllowance(bool _smartContractAllowance) external onlyOwner override {
smartContractAllowance = _smartContractAllowance;
emit SmartContractAllowanceChanged(smartContractAllowance);
}
function setWithdrawalWallet(address payable _withdrawalWallet) external onlyOwner override {
withdrawalWallet = _withdrawalWallet;
emit WithdrawalWalletChanged(withdrawalWallet);
}
function setDevWallet(address payable _devWallet) external onlyOwner override {
devWallet = _devWallet;
emit DevWalletChanged(devWallet);
}
function setMintLimit(uint256 _mintLimit) external onlyOwner override {
mintLimit = _mintLimit;
emit MintLimitChanged(mintLimit);
}
function withdraw() external onlyOwner override {
uint256 contractBalance = address(this).balance;
devWallet.transfer(contractBalance.mul(devSaleShare).div(10000));
withdrawalWallet.transfer(contractBalance.mul(ownerSaleShare).div(10000));
}
function reserve(uint256 _amount) external onlyOwner override {
_mint(_amount);
emit Reserve(_amount);
}
function buy(uint256 _amount) external override payable {
require(saleActive, "Dropspace::buy: Sale is not active.");
require(_amount <= mintLimit, "Dropspace::buy: Too many tokens for one transaction.");
require(msg.value >= mintPrice.mul(_amount), "Dropspace::buy: Insufficient payment.");
if (!smartContractAllowance) {
require(tx.origin == _msgSender(), "Dropspace::buy: Smart contracts are not allowed to buy.");
}
_mint(_amount);
emit Buy(_msgSender(), _amount);
}
function _mint(uint256 _amount) internal {
require(totalSupply().add(_amount) <= supplyLimit, "Not enough tokens left.");
_safeMint(_msgSender(), _amount);
}
function tokenURI(uint256 _tokenId) public view override returns(string memory) {
require(_exists(_tokenId), "ERC721Metadata: URI query for nonexistent token");
return bytes(baseURI).length > 0 ?
string(abi.encodePacked(baseURI, _tokenId.toString())) : "";
}
function togglePresaleActive() external onlyOwner override {
presaleActive = !presaleActive;
emit TogglePresaleState(presaleActive);
}
function setTicketAddress(address _ticketAddress) external onlyOwner override {
require(_ticketAddress != address(0), "DropSpaceSale::setTicketAddress: Invalid address.");
ticketAddress = _ticketAddress;
emit TicketAddressChanged(_ticketAddress);
}
function presaleBuy(uint256 _ticketId, uint _amount) external payable override {
require(presaleActive, "Dropspace::presaleBuy: Presale is not Active.");
require(IERC721(ticketAddress).ownerOf(_ticketId) == _msgSender(), "Dropspace::presaleBuy: invalid ticket.");
require(!usedTickets[_ticketId], "Dropspace::presaleBuy: Ticket already used.");
require(_amount <= mintLimit, "Dropspace::presaleBuy: Too many tokens for one transaction.");
require(msg.value >= mintPrice.mul(_amount), "Dropspace::presaleBuy: Insufficient payment.");
usedTickets[_ticketId] = true;
_mint(_amount);
emit PresaleBuy(_msgSender(), _ticketId, _amount);
}
function _verifyWhitelist(address _user, bytes32[] calldata _merkleProof) internal view returns(bool) {
bytes32 leaf = keccak256(abi.encodePacked(_user));
return MerkleProof.verify(_merkleProof, whitelistRoot, leaf);
}
function whitelistBuy(uint256 _amount, bytes32[] calldata _merkleProof) external payable override {
require(whitelistSaleActive, "DropSpaceSale::whitelistBuy: Whitelist Buy is not Active.");
require(_amount <= mintLimit, "Dropspace::presaleBuy: Too many tokens for one transaction.");
require(msg.value >= mintPrice.mul(_amount), "Dropspace::presaleBuy: Insufficient payment.");
require(_verifyWhitelist(_msgSender(), _merkleProof), "Dropspace::whitelistBuy: User is not whitelisted");
if (whitelistBuyOnce) {
require(!whitelistClaimed[_msgSender()], "Dropspace::whitelistBuy: Already claimed");
_setWhitelistClaimStatus(_msgSender(), true);
}
_mint(_amount);
emit WhitelistBuy(_msgSender(), _amount);
}
function clearTicket(uint256 _ticketId) external override onlyOwner{
require(usedTickets[_ticketId], "Dropspace::clearTicket: Ticket is not used");
usedTickets[_ticketId] = false;
emit TicketCleared(_ticketId);
}
receive() external override payable {}
}
// SPDX-License-Identifier: Unlicense
pragma solidity ^0.8.4;
interface IDropspaceSale {
// OWNER ONLY
function togglePresaleActive() external;
function toggleWhitelistSaleActive() external;
function toggleSaleActive() external;
function setBaseURI(string memory _baseURI) external;
function setWithdrawalWallet(address payable _withdrawalWallet) external;
function setDevWallet(address payable _devWallet) external;
function setDevSaleShare(uint256 _devSaleShare) external;
function setMintLimit(uint256 _mintLimit) external;
function setSmartContractAllowance(bool _smartContractAllowance) external;
function setTicketAddress(address _ticketAddress) external;
function setWhitelistClaimStatus(address _user, bool _status) external;
function changeSupplyLimit(uint256 _supplyLimit) external;
function emergencyWithdraw() external;
function setMintPrice(uint256 _mintPrice) external;
function setWhitelistBuyOnce(bool _whitelistBuyOnce) external;
function setWhitelistRoot(bytes32 _whitelistRoot) external;
function reserve(uint256 _amount) external;
function withdraw() external;
function clearTicket(uint256 _ticketId) external;
// EXTERNAL
function buy(uint256 _amount) external payable;
function presaleBuy(uint256 _ticketId, uint256 _amount) external payable;
function whitelistBuy(uint256 _amount, bytes32[] calldata _merkleProof) external payable;
// VIEW
function supplyLimit() view external returns(uint256);
function mintPrice() view external returns(uint256);
function mintLimit() view external returns(uint256);
function baseURI() view external returns(string memory);
function saleActive() view external returns(bool);
function presaleActive() view external returns(bool);
function whitelistSaleActive() view external returns(bool);
function smartContractAllowance() view external returns(bool);
function devWallet() view external returns(address payable);
function withdrawalWallet() view external returns(address payable);
function ticketAddress() view external returns(address);
function whitelistRoot() view external returns (bytes32);
function usedTickets(uint256 _ticketId) view external returns(bool);
function whitelistClaimed(address _user) view external returns(bool);
function whitelistBuyOnce() view external returns(bool);
// EVENTS
event Reserve(uint256 _amount);
event Mint(address indexed _user, uint256 indexed _tokenId, string _tokenURI);
event ToggleSaleState(bool _state);
event BaseURIChanged(string _baseURI);
event WithdrawalWalletChanged(address payable _newWithdrawalWallet);
event DevWalletChanged(address payable _newDevWallet);
event DevShareSaleChanged(uint256 _devSaleShare);
event MintLimitChanged(uint256 _newMintLimit);
event MintPriceChanged(uint256 _mintPrice);
event SmartContractAllowanceChanged(bool _newSmartContractAllowance);
event TogglePresaleState(bool _preSaleState);
event TicketAddressChanged(address _ticketAddress);
event PresaleBuy(address _user, uint256 _ticketId, uint256 _amount);
event WhitelistBuy(address _user, uint256 _amount);
event Buy(address _user, uint256 _amount);
event WhitelistClaimStatusChanged(address _user, bool _status);
event ToggleWhitelistSaleState(bool _whitelistSaleActive);
event SupplyLimitChanged(uint256 _supplyLimit);
event TicketCleared(uint256 _ticketId);
event WhitelistRootChanged(bytes32 _whitelistRoot);
event WhitelistBuyOnceChanged(bool _whitelistBuyOnce);
receive() external payable;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor() {
_transferOwnership(_msgSender());
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/math/SafeMath.sol)
pragma solidity ^0.8.0;
// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.
/**
* @dev Wrappers over Solidity's arithmetic operations.
*
* NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
* now has built in overflow checking.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
uint256 c = a + b;
if (c < a) return (false, 0);
return (true, c);
}
}
/**
* @dev Returns the substraction of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b > a) return (false, 0);
return (true, a - b);
}
}
/**
* @dev Returns the multiplication of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
if (a == 0) return (true, 0);
uint256 c = a * b;
if (c / a != b) return (false, 0);
return (true, c);
}
}
/**
* @dev Returns the division of two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/
function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b == 0) return (false, 0);
return (true, a / b);
}
}
/**
* @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/
function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b == 0) return (false, 0);
return (true, a % b);
}
}
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
*
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
return a + b;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return a - b;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
*
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
return a * b;
}
/**
* @dev Returns the integer division of two unsigned integers, reverting on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator.
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return a / b;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
return a % b;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on
* overflow (when the result is negative).
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {trySub}.
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
unchecked {
require(b <= a, errorMessage);
return a - b;
}
}
/**
* @dev Returns the integer division of two unsigned integers, reverting with custom message on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
unchecked {
require(b > 0, errorMessage);
return a / b;
}
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting with custom message when dividing by zero.
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {tryMod}.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
unchecked {
require(b > 0, errorMessage);
return a % b;
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Strings.sol)
pragma solidity ^0.8.0;
/**
* @dev String operations.
*/
library Strings {
bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
/**
* @dev Converts a `uint256` to its ASCII `string` decimal representation.
*/
function toString(uint256 value) internal pure returns (string memory) {
// Inspired by OraclizeAPI's implementation - MIT licence
// https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
if (value == 0) {
return "0";
}
uint256 temp = value;
uint256 digits;
while (temp != 0) {
digits++;
temp /= 10;
}
bytes memory buffer = new bytes(digits);
while (value != 0) {
digits -= 1;
buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
value /= 10;
}
return string(buffer);
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
*/
function toHexString(uint256 value) internal pure returns (string memory) {
if (value == 0) {
return "0x00";
}
uint256 temp = value;
uint256 length = 0;
while (temp != 0) {
length++;
temp >>= 8;
}
return toHexString(value, length);
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
*/
function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
bytes memory buffer = new bytes(2 * length + 2);
buffer[0] = "0";
buffer[1] = "x";
for (uint256 i = 2 * length + 1; i > 1; --i) {
buffer[i] = _HEX_SYMBOLS[value & 0xf];
value >>= 4;
}
require(value == 0, "Strings: hex length insufficient");
return string(buffer);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/cryptography/MerkleProof.sol)
pragma solidity ^0.8.0;
/**
* @dev These functions deal with verification of Merkle Trees proofs.
*
* The proofs can be generated using the JavaScript library
* https://github.com/miguelmota/merkletreejs[merkletreejs].
* Note: the hashing algorithm should be keccak256 and pair sorting should be enabled.
*
* See `test/utils/cryptography/MerkleProof.test.js` for some examples.
*/
library MerkleProof {
/**
* @dev Returns true if a `leaf` can be proved to be a part of a Merkle tree
* defined by `root`. For this, a `proof` must be provided, containing
* sibling hashes on the branch from the leaf to the root of the tree. Each
* pair of leaves and each pair of pre-images are assumed to be sorted.
*/
function verify(
bytes32[] memory proof,
bytes32 root,
bytes32 leaf
) internal pure returns (bool) {
return processProof(proof, leaf) == root;
}
/**
* @dev Returns the rebuilt hash obtained by traversing a Merklee tree up
* from `leaf` using `proof`. A `proof` is valid if and only if the rebuilt
* hash matches the root of the tree. When processing the proof, the pairs
* of leafs & pre-images are assumed to be sorted.
*
* _Available since v4.4._
*/
function processProof(bytes32[] memory proof, bytes32 leaf) internal pure returns (bytes32) {
bytes32 computedHash = leaf;
for (uint256 i = 0; i < proof.length; i++) {
bytes32 proofElement = proof[i];
if (computedHash <= proofElement) {
// Hash(current computed hash + current element of the proof)
computedHash = _efficientHash(computedHash, proofElement);
} else {
// Hash(current element of the proof + current computed hash)
computedHash = _efficientHash(proofElement, computedHash);
}
}
return computedHash;
}
function _efficientHash(bytes32 a, bytes32 b) private pure returns (bytes32 value) {
assembly {
mstore(0x00, a)
mstore(0x20, b)
value := keccak256(0x00, 0x40)
}
}
}
// SPDX-License-Identifier: MIT
// Creator: Chiru Labs
pragma solidity ^0.8.4;
import '@openzeppelin/contracts/token/ERC721/IERC721.sol';
import '@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol';
import '@openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol';
import '@openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol';
import '@openzeppelin/contracts/utils/Address.sol';
import '@openzeppelin/contracts/utils/Context.sol';
import '@openzeppelin/contracts/utils/Strings.sol';
import '@openzeppelin/contracts/utils/introspection/ERC165.sol';
error ApprovalCallerNotOwnerNorApproved();
error ApprovalQueryForNonexistentToken();
error ApproveToCaller();
error ApprovalToCurrentOwner();
error BalanceQueryForZeroAddress();
error MintedQueryForZeroAddress();
error BurnedQueryForZeroAddress();
error MintToZeroAddress();
error MintZeroQuantity();
error OwnerIndexOutOfBounds();
error OwnerQueryForNonexistentToken();
error TokenIndexOutOfBounds();
error TransferCallerNotOwnerNorApproved();
error TransferFromIncorrectOwner();
error TransferToNonERC721ReceiverImplementer();
error TransferToZeroAddress();
error URIQueryForNonexistentToken();
/**
* @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
* the Metadata and Enumerable extension. Built to optimize for lower gas during batch mints.
*
* Assumes serials are sequentially minted starting at 0 (e.g. 0, 1, 2, 3..).
*
* Assumes that an owner cannot have more than 2**64 - 1 (max value of uint64) of supply.
*
* Assumes that the maximum token id cannot exceed 2**128 - 1 (max value of uint128).
*/
contract ERC721A is Context, ERC165, IERC721, IERC721Metadata, IERC721Enumerable {
using Address for address;
using Strings for uint256;
// Compiler will pack this into a single 256bit word.
struct TokenOwnership {
// The address of the owner.
address addr;
// Keeps track of the start time of ownership with minimal overhead for tokenomics.
uint64 startTimestamp;
// Whether the token has been burned.
bool burned;
}
// Compiler will pack this into a single 256bit word.
struct AddressData {
// Realistically, 2**64-1 is more than enough.
uint64 balance;
// Keeps track of mint count with minimal overhead for tokenomics.
uint64 numberMinted;
// Keeps track of burn count with minimal overhead for tokenomics.
uint64 numberBurned;
}
// Compiler will pack the following
// _currentIndex and _burnCounter into a single 256bit word.
// The tokenId of the next token to be minted.
uint128 internal _currentIndex;
// The number of tokens burned.
uint128 internal _burnCounter;
// Token name
string private _name;
// Token symbol
string private _symbol;
// Mapping from token ID to ownership details
// An empty struct value does not necessarily mean the token is unowned. See ownershipOf implementation for details.
mapping(uint256 => TokenOwnership) internal _ownerships;
// Mapping owner address to address data
mapping(address => AddressData) private _addressData;
// 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;
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
}
/**
* @dev See {IERC721Enumerable-totalSupply}.
*/
function totalSupply() public view override returns (uint256) {
// Counter underflow is impossible as _burnCounter cannot be incremented
// more than _currentIndex times
unchecked {
return _currentIndex - _burnCounter;
}
}
/**
* @dev See {IERC721Enumerable-tokenByIndex}.
* This read function is O(totalSupply). If calling from a separate contract, be sure to test gas first.
* It may also degrade with extremely large collection sizes (e.g >> 10000), test for your use case.
*/
function tokenByIndex(uint256 index) public view override returns (uint256) {
uint256 numMintedSoFar = _currentIndex;
uint256 tokenIdsIdx;
// Counter overflow is impossible as the loop breaks when
// uint256 i is equal to another uint256 numMintedSoFar.
unchecked {
for (uint256 i; i < numMintedSoFar; i++) {
TokenOwnership memory ownership = _ownerships[i];
if (!ownership.burned) {
if (tokenIdsIdx == index) {
return i;
}
tokenIdsIdx++;
}
}
}
revert TokenIndexOutOfBounds();
}
/**
* @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
* This read function is O(totalSupply). If calling from a separate contract, be sure to test gas first.
* It may also degrade with extremely large collection sizes (e.g >> 10000), test for your use case.
*/
function tokenOfOwnerByIndex(address owner, uint256 index) public view override returns (uint256) {
if (index >= balanceOf(owner)) revert OwnerIndexOutOfBounds();
uint256 numMintedSoFar = _currentIndex;
uint256 tokenIdsIdx;
address currOwnershipAddr;
// Counter overflow is impossible as the loop breaks when
// uint256 i is equal to another uint256 numMintedSoFar.
unchecked {
for (uint256 i; i < numMintedSoFar; i++) {
TokenOwnership memory ownership = _ownerships[i];
if (ownership.burned) {
continue;
}
if (ownership.addr != address(0)) {
currOwnershipAddr = ownership.addr;
}
if (currOwnershipAddr == owner) {
if (tokenIdsIdx == index) {
return i;
}
tokenIdsIdx++;
}
}
}
// Execution should never reach this point.
revert();
}
/**
* @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 ||
interfaceId == type(IERC721Enumerable).interfaceId ||
super.supportsInterface(interfaceId);
}
/**
* @dev See {IERC721-balanceOf}.
*/
function balanceOf(address owner) public view override returns (uint256) {
if (owner == address(0)) revert BalanceQueryForZeroAddress();
return uint256(_addressData[owner].balance);
}
function _numberMinted(address owner) internal view returns (uint256) {
if (owner == address(0)) revert MintedQueryForZeroAddress();
return uint256(_addressData[owner].numberMinted);
}
function _numberBurned(address owner) internal view returns (uint256) {
if (owner == address(0)) revert BurnedQueryForZeroAddress();
return uint256(_addressData[owner].numberBurned);
}
/**
* Gas spent here starts off proportional to the maximum mint batch size.
* It gradually moves to O(1) as tokens get transferred around in the collection over time.
*/
function ownershipOf(uint256 tokenId) internal view returns (TokenOwnership memory) {
uint256 curr = tokenId;
unchecked {
if (curr < _currentIndex) {
TokenOwnership memory ownership = _ownerships[curr];
if (!ownership.burned) {
if (ownership.addr != address(0)) {
return ownership;
}
// Invariant:
// There will always be an ownership that has an address and is not burned
// before an ownership that does not have an address and is not burned.
// Hence, curr will not underflow.
while (true) {
curr--;
ownership = _ownerships[curr];
if (ownership.addr != address(0)) {
return ownership;
}
}
}
}
}
revert OwnerQueryForNonexistentToken();
}
/**
* @dev See {IERC721-ownerOf}.
*/
function ownerOf(uint256 tokenId) public view override returns (address) {
return ownershipOf(tokenId).addr;
}
/**
* @dev See {IERC721Metadata-name}.
*/
function name() public view virtual override returns (string memory) {
return _name;
}
/**
* @dev See {IERC721Metadata-symbol}.
*/
function symbol() public view virtual override returns (string memory) {
return _symbol;
}
/**
* @dev See {IERC721Metadata-tokenURI}.
*/
function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
if (!_exists(tokenId)) revert URIQueryForNonexistentToken();
string memory baseURI = _baseURI();
return bytes(baseURI).length != 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : '';
}
/**
* @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
* token will be the concatenation of the `baseURI` and the `tokenId`. Empty
* by default, can be overriden in child contracts.
*/
function _baseURI() internal view virtual returns (string memory) {
return '';
}
/**
* @dev See {IERC721-approve}.
*/
function approve(address to, uint256 tokenId) public override {
address owner = ERC721A.ownerOf(tokenId);
if (to == owner) revert ApprovalToCurrentOwner();
if (_msgSender() != owner && !isApprovedForAll(owner, _msgSender())) {
revert ApprovalCallerNotOwnerNorApproved();
}
_approve(to, tokenId, owner);
}
/**
* @dev See {IERC721-getApproved}.
*/
function getApproved(uint256 tokenId) public view override returns (address) {
if (!_exists(tokenId)) revert ApprovalQueryForNonexistentToken();
return _tokenApprovals[tokenId];
}
/**
* @dev See {IERC721-setApprovalForAll}.
*/
function setApprovalForAll(address operator, bool approved) public override {
if (operator == _msgSender()) revert ApproveToCaller();
_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 {
_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 {
_transfer(from, to, tokenId);
if (!_checkOnERC721Received(from, to, tokenId, _data)) {
revert TransferToNonERC721ReceiverImplementer();
}
}
/**
* @dev Returns whether `tokenId` exists.
*
* Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
*
* Tokens start existing when they are minted (`_mint`),
*/
function _exists(uint256 tokenId) internal view returns (bool) {
return tokenId < _currentIndex && !_ownerships[tokenId].burned;
}
function _safeMint(address to, uint256 quantity) internal {
_safeMint(to, quantity, '');
}
/**
* @dev Safely mints `quantity` tokens and transfers them to `to`.
*
* Requirements:
*
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called for each safe transfer.
* - `quantity` must be greater than 0.
*
* Emits a {Transfer} event.
*/
function _safeMint(
address to,
uint256 quantity,
bytes memory _data
) internal {
_mint(to, quantity, _data, true);
}
/**
* @dev Mints `quantity` tokens and transfers them to `to`.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - `quantity` must be greater than 0.
*
* Emits a {Transfer} event.
*/
function _mint(
address to,
uint256 quantity,
bytes memory _data,
bool safe
) internal {
uint256 startTokenId = _currentIndex;
if (to == address(0)) revert MintToZeroAddress();
if (quantity == 0) revert MintZeroQuantity();
_beforeTokenTransfers(address(0), to, startTokenId, quantity);
// Overflows are incredibly unrealistic.
// balance or numberMinted overflow if current value of either + quantity > 3.4e38 (2**128) - 1
// updatedIndex overflows if _currentIndex + quantity > 3.4e38 (2**128) - 1
unchecked {
_addressData[to].balance += uint64(quantity);
_addressData[to].numberMinted += uint64(quantity);
_ownerships[startTokenId].addr = to;
_ownerships[startTokenId].startTimestamp = uint64(block.timestamp);
uint256 updatedIndex = startTokenId;
for (uint256 i; i < quantity; i++) {
emit Transfer(address(0), to, updatedIndex);
if (safe && !_checkOnERC721Received(address(0), to, updatedIndex, _data)) {
revert TransferToNonERC721ReceiverImplementer();
}
updatedIndex++;
}
_currentIndex = uint128(updatedIndex);
}
_afterTokenTransfers(address(0), to, startTokenId, quantity);
}
/**
* @dev Transfers `tokenId` from `from` to `to`.
*
* 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
) private {
TokenOwnership memory prevOwnership = ownershipOf(tokenId);
bool isApprovedOrOwner = (_msgSender() == prevOwnership.addr ||
isApprovedForAll(prevOwnership.addr, _msgSender()) ||
getApproved(tokenId) == _msgSender());
if (!isApprovedOrOwner) revert TransferCallerNotOwnerNorApproved();
if (prevOwnership.addr != from) revert TransferFromIncorrectOwner();
if (to == address(0)) revert TransferToZeroAddress();
_beforeTokenTransfers(from, to, tokenId, 1);
// Clear approvals from the previous owner
_approve(address(0), tokenId, prevOwnership.addr);
// Underflow of the sender's balance is impossible because we check for
// ownership above and the recipient's balance can't realistically overflow.
// Counter overflow is incredibly unrealistic as tokenId would have to be 2**128.
unchecked {
_addressData[from].balance -= 1;
_addressData[to].balance += 1;
_ownerships[tokenId].addr = to;
_ownerships[tokenId].startTimestamp = uint64(block.timestamp);
// If the ownership slot of tokenId+1 is not explicitly set, that means the transfer initiator owns it.
// Set the slot of tokenId+1 explicitly in storage to maintain correctness for ownerOf(tokenId+1) calls.
uint256 nextTokenId = tokenId + 1;
if (_ownerships[nextTokenId].addr == address(0)) {
// This will suffice for checking _exists(nextTokenId),
// as a burned slot cannot contain the zero address.
if (nextTokenId < _currentIndex) {
_ownerships[nextTokenId].addr = prevOwnership.addr;
_ownerships[nextTokenId].startTimestamp = prevOwnership.startTimestamp;
}
}
}
emit Transfer(from, to, tokenId);
_afterTokenTransfers(from, to, tokenId, 1);
}
/**
* @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 {
TokenOwnership memory prevOwnership = ownershipOf(tokenId);
_beforeTokenTransfers(prevOwnership.addr, address(0), tokenId, 1);
// Clear approvals from the previous owner
_approve(address(0), tokenId, prevOwnership.addr);
// Underflow of the sender's balance is impossible because we check for
// ownership above and the recipient's balance can't realistically overflow.
// Counter overflow is incredibly unrealistic as tokenId would have to be 2**128.
unchecked {
_addressData[prevOwnership.addr].balance -= 1;
_addressData[prevOwnership.addr].numberBurned += 1;
// Keep track of who burned the token, and the timestamp of burning.
_ownerships[tokenId].addr = prevOwnership.addr;
_ownerships[tokenId].startTimestamp = uint64(block.timestamp);
_ownerships[tokenId].burned = true;
// If the ownership slot of tokenId+1 is not explicitly set, that means the burn initiator owns it.
// Set the slot of tokenId+1 explicitly in storage to maintain correctness for ownerOf(tokenId+1) calls.
uint256 nextTokenId = tokenId + 1;
if (_ownerships[nextTokenId].addr == address(0)) {
// This will suffice for checking _exists(nextTokenId),
// as a burned slot cannot contain the zero address.
if (nextTokenId < _currentIndex) {
_ownerships[nextTokenId].addr = prevOwnership.addr;
_ownerships[nextTokenId].startTimestamp = prevOwnership.startTimestamp;
}
}
}
emit Transfer(prevOwnership.addr, address(0), tokenId);
_afterTokenTransfers(prevOwnership.addr, address(0), tokenId, 1);
// Overflow not possible, as _burnCounter cannot be exceed _currentIndex times.
unchecked {
_burnCounter++;
}
}
/**
* @dev Approve `to` to operate on `tokenId`
*
* Emits a {Approval} event.
*/
function _approve(
address to,
uint256 tokenId,
address owner
) private {
_tokenApprovals[tokenId] = to;
emit Approval(owner, 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 TransferToNonERC721ReceiverImplementer();
} else {
assembly {
revert(add(32, reason), mload(reason))
}
}
}
} else {
return true;
}
}
/**
* @dev Hook that is called before a set of serially-ordered token ids are about to be transferred. This includes minting.
* And also called before burning one token.
*
* startTokenId - the first token id to be transferred
* quantity - the amount to be transferred
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, `from`'s `tokenId` will be
* transferred to `to`.
* - When `from` is zero, `tokenId` will be minted for `to`.
* - When `to` is zero, `tokenId` will be burned by `from`.
* - `from` and `to` are never both zero.
*/
function _beforeTokenTransfers(
address from,
address to,
uint256 startTokenId,
uint256 quantity
) internal virtual {}
/**
* @dev Hook that is called after a set of serially-ordered token ids have been transferred. This includes
* minting.
* And also called after one token has been burned.
*
* startTokenId - the first token id to be transferred
* quantity - the amount to be transferred
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, `from`'s `tokenId` has been
* transferred to `to`.
* - When `from` is zero, `tokenId` has been minted for `to`.
* - When `to` is zero, `tokenId` has been burned by `from`.
* - `from` and `to` are never both zero.
*/
function _afterTokenTransfers(
address from,
address to,
uint256 startTokenId,
uint256 quantity
) internal virtual {}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721.sol)
pragma solidity ^0.8.0;
import "../../utils/introspection/IERC165.sol";
/**
* @dev Required interface of an ERC721 compliant contract.
*/
interface IERC721 is IERC165 {
/**
* @dev Emitted when `tokenId` token is transferred from `from` to `to`.
*/
event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
*/
event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
*/
event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
/**
* @dev Returns the number of tokens in ``owner``'s account.
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @dev Returns the owner of the `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function ownerOf(uint256 tokenId) external view returns (address owner);
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
* are aware of the ERC721 protocol to prevent tokens from being forever locked.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId
) external;
/**
* @dev Transfers `tokenId` token from `from` to `to`.
*
* WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
*
* Emits a {Transfer} event.
*/
function transferFrom(
address from,
address to,
uint256 tokenId
) external;
/**
* @dev Gives permission to `to` to transfer `tokenId` token to another account.
* The approval is cleared when the token is transferred.
*
* Only a single account can be approved at a time, so approving the zero address clears previous approvals.
*
* Requirements:
*
* - The caller must own the token or be an approved operator.
* - `tokenId` must exist.
*
* Emits an {Approval} event.
*/
function approve(address to, uint256 tokenId) external;
/**
* @dev Returns the account approved for `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function getApproved(uint256 tokenId) external view returns (address operator);
/**
* @dev Approve or remove `operator` as an operator for the caller.
* Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
*
* Requirements:
*
* - The `operator` cannot be the caller.
*
* Emits an {ApprovalForAll} event.
*/
function setApprovalForAll(address operator, bool _approved) external;
/**
* @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
*
* See {setApprovalForAll}
*/
function isApprovedForAll(address owner, address operator) external view returns (bool);
/**
* @dev Safely transfers `tokenId` token from `from` to `to`.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId,
bytes calldata data
) external;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721Receiver.sol)
pragma solidity ^0.8.0;
/**
* @title ERC721 token receiver interface
* @dev Interface for any contract that wants to support safeTransfers
* from ERC721 asset contracts.
*/
interface IERC721Receiver {
/**
* @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
* by `operator` from `from`, this function is called.
*
* It must return its Solidity selector to confirm the token transfer.
* If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
*
* The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.
*/
function onERC721Received(
address operator,
address from,
uint256 tokenId,
bytes calldata data
) external returns (bytes4);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)
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
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC721/extensions/IERC721Enumerable.sol)
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);
/**
* @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
// OpenZeppelin Contracts (last updated v4.5.0) (utils/Address.sol)
pragma solidity ^0.8.1;
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*
* [IMPORTANT]
* ====
* You shouldn't rely on `isContract` to protect against flash loan attacks!
*
* Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
* like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
* constructor.
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize/address.code.length, which returns 0
// for contracts in construction, since the code is only stored at the end
// of the constructor execution.
return account.code.length > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return 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
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
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
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC165 standard, as defined in the
* https://eips.ethereum.org/EIPS/eip-165[EIP].
*
* Implementers can declare support of contract interfaces, which can then be
* queried by others ({ERC165Checker}).
*
* For an implementation, see {ERC165}.
*/
interface IERC165 {
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
* to learn more about how these ids are created.
*
* This function call must use less than 30 000 gas.
*/
function supportsInterface(bytes4 interfaceId) external view returns (bool);
}