Contract Name:
MonsterSatoshible
Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;
/**
* __ __ _
* | \/ | ___ _ __ ___| |_ ___ _ __
* | |\/| |/ _ \| '_ \/ __| __/ _ \ '__|
* | | | | (_) | | | \__ \ || __/ |
* |_|__|_|\___/|_| |_|___/\__\___|_|_ _
* / ___| __ _| |_ ___ ___| |__ (_) |__ | | ___ ___
* \___ \ / _` | __/ _ \/ __| '_ \| | '_ \| |/ _ \/ __|
* ___) | (_| | || (_) \__ \ | | | | |_) | | __/\__ \
* |____/ \__,_|\__\___/|___/_| |_|_|_.__/|_|\___||___/
*
*/
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@openzeppelin/contracts/utils/Counters.sol";
import "@openzeppelin/contracts/utils/introspection/ERC165.sol";
import "./ERC2981ContractWideRoyalties.sol";
import "./MerkleProof.sol";
/**
* @notice Original Satoshibles contract interface
*/
interface ISatoshible {
function ownerOf(
uint256 _tokenId
)
external
view
returns (address owner);
}
/**
* @title Monster Satoshibles
* @notice NFT of monsters that can be burned and combined into prime monsters!
* @author Aaron Hanson
*/
contract MonsterSatoshible is ERC721, ERC2981ContractWideRoyalties, Ownable {
/// The max token supply
uint256 public constant MAX_SUPPLY = 6666;
/// The presale portion of the max supply
uint256 public constant MAX_PRESALE_SUPPLY = 3333;
/// Mysterious constants 💀
uint256 constant DEATH = 0xDEAD;
uint256 constant LIFE = 0x024350AC;
uint256 constant ALPHA = LIFE % DEATH * 1000;
uint256 constant OMEGA = LIFE % DEATH + ALPHA;
/// Prime types
uint256 constant FRANKENSTEIN = 0;
uint256 constant WEREWOLF = 1;
uint256 constant VAMPIRE = 2;
uint256 constant ZOMBIE = 3;
uint256 constant INVALID = 4;
/// Number of prime parts
uint256 constant NUM_PARTS = 4;
/// Bitfield mask for prime part detection during prime minting
uint256 constant HAS_ALL_PARTS = 2 ** NUM_PARTS - 1;
/// Merkle root summarizing the presale whitelist
bytes32 public constant WHITELIST_MERKLE_ROOT =
0xdb6eea27a6a35a02d1928e9582f75c1e0a518ad5992b5cfee9cc0d86fb387b8d;
/// Additional team wallets (can withdraw)
address public constant TEAM_WALLET_A =
0xF746362D8162Eeb3624c17654FFAa6EB8bD71820;
address public constant TEAM_WALLET_B =
0x16659F9D2ab9565B0c07199687DE3634c0965391;
address public constant TEAM_WALLET_C =
0x7a73f770873761054ab7757E909ae48f771379D4;
address public constant TEAM_WALLET_D =
0xB7c7e3809591F720f3a75Fb3efa05E76E6B7B92A;
/// The maximum ERC-2981 royalties percentage
uint256 public constant MAX_ROYALTIES_PCT = 600;
/// Original Satoshibles contract instance
ISatoshible public immutable SATOSHIBLE_CONTRACT;
/// The max presale token ID
uint256 public immutable MAX_PRESALE_TOKEN_ID;
/// The current token supply
uint256 public totalSupply;
/// The current state of the sale
bool public saleIsActive;
/// Indicates if the public sale was opened manually
bool public publicSaleOpenedEarly;
/// The default and discount token prices in wei
uint256 public tokenPrice = 99900000000000000; // 0.0999 ether
uint256 public discountPrice = 66600000000000000; // 0.0666 ether
/// Tracks number of presale mints already used per address
mapping(address => uint256) public whitelistMintsUsed;
/// The current state of the laboratory
bool public laboratoryHasElectricity;
/// Merkle root summarizing all monster IDs and their prime parts
bytes32 public primePartsMerkleRoot;
/// The provenance URI
string public provenanceURI = "Not Yet Set";
/// When true, the provenanceURI can no longer be changed
bool public provenanceUriLocked;
/// The base URI
string public baseURI = "https://api.satoshibles.com/monsters/token/";
/// When true, the baseURI can no longer be changed
bool public baseUriLocked;
/// Use Counters for token IDs
using Counters for Counters.Counter;
/// Monster token ID counter
Counters.Counter monsterIds;
/// Prime token ID counter for each prime type
mapping(uint256 => Counters.Counter) primeIds;
/// Prime ID offsets for each prime type
mapping(uint256 => uint256) primeIdOffset;
/// Bitfields that track original Satoshibles already used for discounts
mapping(uint256 => uint256) satDiscountBitfields;
/// Bitfields that track original Satoshibles already used in lab
mapping(uint256 => uint256) satLabBitfields;
/**
* @notice Emitted when the saleIsActive flag changes
* @param isActive Indicates whether or not the sale is now active
*/
event SaleStateChanged(
bool indexed isActive
);
/**
* @notice Emitted when the public sale is opened early
*/
event PublicSaleOpenedEarly();
/**
* @notice Emitted when the laboratoryHasElectricity flag changes
* @param hasElectricity Indicates whether or not the laboratory is open
*/
event LaboratoryStateChanged(
bool indexed hasElectricity
);
/**
* @notice Emitted when a prime is created in the lab
* @param creator The account that created the prime
* @param primeId The ID of the prime created
* @param satId The Satoshible used as the 'key' to the lab
* @param monsterIdsBurned The IDs of the monsters burned
*/
event PrimeCreated(
address indexed creator,
uint256 indexed primeId,
uint256 indexed satId,
uint256[4] monsterIdsBurned
);
/**
* @notice Requires the specified Satoshible to be owned by msg.sender
* @param _satId Original Satoshible token ID
*/
modifier onlySatHolder(
uint256 _satId
) {
require(
SATOSHIBLE_CONTRACT.ownerOf(_satId) == _msgSender(),
"Sat not owned"
);
_;
}
/**
* @notice Requires msg.sender to be the owner or a team wallet
*/
modifier onlyTeam() {
require(
_msgSender() == TEAM_WALLET_A
|| _msgSender() == TEAM_WALLET_B
|| _msgSender() == TEAM_WALLET_C
|| _msgSender() == TEAM_WALLET_D
|| _msgSender() == owner(),
"Not owner or team address"
);
_;
}
/**
* @notice Boom... Let's go!
* @param _initialBatchCount Number of tokens to mint to msg.sender
* @param _immutableSatoshible Original Satoshible contract address
* @param _royaltiesPercentage Initial royalties percentage for ERC-2981
*/
constructor(
uint256 _initialBatchCount,
address _immutableSatoshible,
uint256 _royaltiesPercentage
)
ERC721("Monster Satoshibles", "MSBLS")
{
SATOSHIBLE_CONTRACT = ISatoshible(
_immutableSatoshible
);
require(
_royaltiesPercentage <= MAX_ROYALTIES_PCT,
"Royalties too high"
);
_setRoyalties(
_msgSender(),
_royaltiesPercentage
);
_initializePrimeIdOffsets();
_initializeSatDiscountAvailability();
_initializeSatLabAvailability();
_mintTokens(_initialBatchCount);
require(
belowMaximum(_initialBatchCount, MAX_PRESALE_SUPPLY,
MAX_SUPPLY
) == true,
"Would exceed max supply"
);
unchecked {
MAX_PRESALE_TOKEN_ID = _initialBatchCount + MAX_PRESALE_SUPPLY;
}
}
/**
* @notice Mints monster tokens during presale, optionally with discounts
* @param _numberOfTokens Number of tokens to mint
* @param _satsForDiscount Array of Satoshible IDs for discounted mints
* @param _whitelistedTokens Account's total number of whitelisted tokens
* @param _proof Merkle proof to be verified
*/
function mintTokensPresale(
uint256 _numberOfTokens,
uint256[] calldata _satsForDiscount,
uint256 _whitelistedTokens,
bytes32[] calldata _proof
)
external
payable
{
require(
publicSaleOpenedEarly == false,
"Presale has ended"
);
require(
belowMaximum(monsterIds.current(), _numberOfTokens,
MAX_PRESALE_TOKEN_ID
) == true,
"Would exceed presale size"
);
require(
belowMaximum(whitelistMintsUsed[_msgSender()], _numberOfTokens,
_whitelistedTokens
) == true,
"Would exceed whitelisted count"
);
require(
verifyWhitelisted(_msgSender(), _whitelistedTokens,
_proof
) == true,
"Invalid whitelist proof"
);
whitelistMintsUsed[_msgSender()] += _numberOfTokens;
_doMintTokens(
_numberOfTokens,
_satsForDiscount
);
}
/**
* @notice Mints monsters during public sale, optionally with discounts
* @param _numberOfTokens Number of monster tokens to mint
* @param _satsForDiscount Array of Satoshible IDs for discounted mints
*/
function mintTokensPublicSale(
uint256 _numberOfTokens,
uint256[] calldata _satsForDiscount
)
external
payable
{
require(
publicSaleOpened() == true,
"Public sale has not started"
);
require(
belowMaximum(monsterIds.current(), _numberOfTokens,
MAX_SUPPLY
) == true,
"Not enough tokens left"
);
_doMintTokens(
_numberOfTokens,
_satsForDiscount
);
}
/**
* @notice Mints a prime token by burning two or more monster tokens
* @param _primeType Prime type to mint
* @param _satId Original Satoshible token ID to use as 'key' to the lab
* @param _monsterIds Array of monster token IDs to potentially be burned
* @param _monsterPrimeParts Array of bitfields of monsters' prime parts
* @param _proofs Array of merkle proofs to be verified
*/
function mintPrimeToken(
uint256 _primeType,
uint256 _satId,
uint256[] calldata _monsterIds,
uint256[] calldata _monsterPrimeParts,
bytes32[][] calldata _proofs
)
external
onlySatHolder(_satId)
{
require(
laboratoryHasElectricity == true,
"Prime laboratory not yet open"
);
require(
_primeType < INVALID,
"Invalid prime type"
);
require(
belowMaximum(
primeIdOffset[_primeType],
primeIds[_primeType].current() + 1,
primeIdOffset[_primeType + 1]
) == true,
"No more primes left of this type"
);
require(
satIsAvailableForLab(_satId) == true,
"Sat has already been used in lab"
);
// bitfield tracking aggregate parts across monsters
// (head = 1, eyes = 2, mouth = 4, body = 8)
uint256 combinedParts;
uint256[4] memory burnedIds;
unchecked {
uint256 burnedIndex;
for (uint256 i = 0; i < _monsterIds.length; i++) {
require(
verifyMonsterPrimeParts(
_monsterIds[i],
_monsterPrimeParts[i],
_proofs[i]
) == true,
"Invalid monster traits proof"
);
uint256 theseParts = _monsterPrimeParts[i]
>> (_primeType * NUM_PARTS) & HAS_ALL_PARTS;
if (combinedParts | theseParts != combinedParts) {
_burn(
_monsterIds[i]
);
burnedIds[burnedIndex++] = _monsterIds[i];
combinedParts |= theseParts;
if (combinedParts == HAS_ALL_PARTS) {
break;
}
}
}
}
require(
combinedParts == HAS_ALL_PARTS,
"Not enough parts for this prime"
);
_retireSatFromLab(_satId);
primeIds[_primeType].increment();
unchecked {
uint256 primeId = primeIdOffset[_primeType]
+ primeIds[_primeType].current();
totalSupply++;
_safeMint(
_msgSender(),
primeId
);
emit PrimeCreated(
_msgSender(),
primeId,
_satId,
burnedIds
);
}
}
/**
* @notice Activates or deactivates the sale
* @param _isActive Whether to activate or deactivate the sale
*/
function activateSale(
bool _isActive
)
external
onlyOwner
{
saleIsActive = _isActive;
emit SaleStateChanged(
_isActive
);
}
/**
* @notice Starts the public sale before MAX_PRESALE_TOKEN_ID is minted
*/
function openPublicSaleEarly()
external
onlyOwner
{
publicSaleOpenedEarly = true;
emit PublicSaleOpenedEarly();
}
/**
* @notice Modifies the prices in case of major ETH price changes
* @param _tokenPrice The new default token price
* @param _discountPrice The new discount token price
*/
function updateTokenPrices(
uint256 _tokenPrice,
uint256 _discountPrice
)
external
onlyOwner
{
require(
_tokenPrice >= _discountPrice,
"discountPrice cannot be larger"
);
require(
saleIsActive == false,
"Sale is active"
);
tokenPrice = _tokenPrice;
discountPrice = _discountPrice;
}
/**
* @notice Sets primePartsMerkleRoot summarizing all monster prime parts
* @param _merkleRoot The new merkle root
*/
function setPrimePartsMerkleRoot(
bytes32 _merkleRoot
)
external
onlyOwner
{
primePartsMerkleRoot = _merkleRoot;
}
/**
* @notice Turns the laboratory on or off
* @param _hasElectricity Whether to turn the laboratory on or off
*/
function electrifyLaboratory(
bool _hasElectricity
)
external
onlyOwner
{
laboratoryHasElectricity = _hasElectricity;
emit LaboratoryStateChanged(
_hasElectricity
);
}
/**
* @notice Mints the final prime token
*/
function mintFinalPrime()
external
onlyOwner
{
require(
_exists(OMEGA) == false,
"Final prime already exists"
);
unchecked {
totalSupply++;
}
_safeMint(
_msgSender(),
OMEGA
);
}
/**
* @notice Sets the provenance URI
* @param _newProvenanceURI The new provenance URI
*/
function setProvenanceURI(
string calldata _newProvenanceURI
)
external
onlyOwner
{
require(
provenanceUriLocked == false,
"Provenance URI has been locked"
);
provenanceURI = _newProvenanceURI;
}
/**
* @notice Prevents further changes to the provenance URI
*/
function lockProvenanceURI()
external
onlyOwner
{
provenanceUriLocked = true;
}
/**
* @notice Sets a new base URI
* @param _newBaseURI The new base URI
*/
function setBaseURI(
string calldata _newBaseURI
)
external
onlyOwner
{
require(
baseUriLocked == false,
"Base URI has been locked"
);
baseURI = _newBaseURI;
}
/**
* @notice Prevents further changes to the base URI
*/
function lockBaseURI()
external
onlyOwner
{
baseUriLocked = true;
}
/**
* @notice Withdraws sale proceeds
* @param _amount Amount to withdraw in wei
*/
function withdraw(
uint256 _amount
)
external
onlyTeam
{
payable(_msgSender()).transfer(
_amount
);
}
/**
* @notice Withdraws any other tokens
* @dev WARNING: Double check token is legit before calling this
* @param _token Contract address of token
* @param _to Address to which to withdraw
* @param _amount Amount to withdraw
* @param _hasVerifiedToken Must be true (sanity check)
*/
function withdrawOther(
address _token,
address _to,
uint256 _amount,
bool _hasVerifiedToken
)
external
onlyOwner
{
require(
_hasVerifiedToken == true,
"Need to verify token"
);
IERC20(_token).transfer(
_to,
_amount
);
}
/**
* @notice Sets token royalties (ERC-2981)
* @param _recipient Recipient of the royalties
* @param _value Royalty percentage (using 2 decimals - 10000 = 100, 0 = 0)
*/
function setRoyalties(
address _recipient,
uint256 _value
)
external
onlyOwner
{
require(
_value <= MAX_ROYALTIES_PCT,
"Royalties too high"
);
_setRoyalties(
_recipient,
_value
);
}
/**
* @notice Checks which Satoshibles can still be used for a discounted mint
* @dev Uses bitwise operators to find the bit representing each Satoshible
* @param _satIds Array of original Satoshible token IDs
* @return Token ID for each of the available _satIds, zero otherwise
*/
function satsAvailableForDiscountMint(
uint256[] calldata _satIds
)
external
view
returns (uint256[] memory)
{
uint256[] memory satsAvailable = new uint256[](_satIds.length);
unchecked {
for (uint256 i = 0; i < _satIds.length; i++) {
if (satIsAvailableForDiscountMint(_satIds[i])) {
satsAvailable[i] = _satIds[i];
}
}
}
return satsAvailable;
}
/**
* @notice Checks which Satoshibles can still be used to mint a prime
* @dev Uses bitwise operators to find the bit representing each Satoshible
* @param _satIds Array of original Satoshible token IDs
* @return Token ID for each of the available _satIds, zero otherwise
*/
function satsAvailableForLab(
uint256[] calldata _satIds
)
external
view
returns (uint256[] memory)
{
uint256[] memory satsAvailable = new uint256[](_satIds.length);
unchecked {
for (uint256 i = 0; i < _satIds.length; i++) {
if (satIsAvailableForLab(_satIds[i])) {
satsAvailable[i] = _satIds[i];
}
}
}
return satsAvailable;
}
/**
* @notice Checks if a Satoshible can still be used for a discounted mint
* @dev Uses bitwise operators to find the bit representing the Satoshible
* @param _satId Original Satoshible token ID
* @return isAvailable True if _satId can be used for a discounted mint
*/
function satIsAvailableForDiscountMint(
uint256 _satId
)
public
view
returns (bool isAvailable)
{
unchecked {
uint256 page = _satId / 256;
uint256 shift = _satId % 256;
isAvailable = satDiscountBitfields[page] >> shift & 1 == 1;
}
}
/**
* @notice Checks if a Satoshible can still be used to mint a prime
* @dev Uses bitwise operators to find the bit representing the Satoshible
* @param _satId Original Satoshible token ID
* @return isAvailable True if _satId can still be used to mint a prime
*/
function satIsAvailableForLab(
uint256 _satId
)
public
view
returns (bool isAvailable)
{
unchecked {
uint256 page = _satId / 256;
uint256 shift = _satId % 256;
isAvailable = satLabBitfields[page] >> shift & 1 == 1;
}
}
/**
* @notice Verifies a merkle proof for a monster ID and its prime parts
* @param _monsterId Monster token ID
* @param _monsterPrimeParts Bitfield of the monster's prime parts
* @param _proof Merkle proof be verified
* @return isVerified True if the merkle proof is verified
*/
function verifyMonsterPrimeParts(
uint256 _monsterId,
uint256 _monsterPrimeParts,
bytes32[] calldata _proof
)
public
view
returns (bool isVerified)
{
bytes32 node = keccak256(
abi.encodePacked(
_monsterId,
_monsterPrimeParts
)
);
isVerified = MerkleProof.verify(
_proof,
primePartsMerkleRoot,
node
);
}
/**
* @notice Gets total count of existing prime tokens for a prime type
* @param _primeType Prime type
* @return supply Count of existing prime tokens for this prime type
*/
function primeSupply(
uint256 _primeType
)
public
view
returns (uint256 supply)
{
supply = primeIds[_primeType].current();
}
/**
* @notice Gets total count of existing prime tokens
* @return supply Count of existing prime tokens
*/
function totalPrimeSupply()
public
view
returns (uint256 supply)
{
unchecked {
supply = primeSupply(FRANKENSTEIN)
+ primeSupply(WEREWOLF)
+ primeSupply(VAMPIRE)
+ primeSupply(ZOMBIE)
+ (_exists(OMEGA) ? 1 : 0);
}
}
/**
* @notice Gets total count of monsters burned
* @return burned Count of monsters burned
*/
function monstersBurned()
public
view
returns (uint256 burned)
{
unchecked {
burned = monsterIds.current() + totalPrimeSupply() - totalSupply;
}
}
/**
* @notice Gets state of public sale
* @return publicSaleIsOpen True if public sale phase has begun
*/
function publicSaleOpened()
public
view
returns (bool publicSaleIsOpen)
{
publicSaleIsOpen =
publicSaleOpenedEarly == true ||
monsterIds.current() >= MAX_PRESALE_TOKEN_ID;
}
/// @inheritdoc ERC165
function supportsInterface(
bytes4 _interfaceId
)
public
view
override (ERC721, ERC2981Base)
returns (bool doesSupportInterface)
{
doesSupportInterface = super.supportsInterface(_interfaceId);
}
/**
* @notice Verifies a merkle proof for an account's whitelisted tokens
* @param _account Account to verify
* @param _whitelistedTokens Number of whitelisted tokens for _account
* @param _proof Merkle proof to be verified
* @return isVerified True if the merkle proof is verified
*/
function verifyWhitelisted(
address _account,
uint256 _whitelistedTokens,
bytes32[] calldata _proof
)
public
pure
returns (bool isVerified)
{
bytes32 node = keccak256(
abi.encodePacked(
_account,
_whitelistedTokens
)
);
isVerified = MerkleProof.verify(
_proof,
WHITELIST_MERKLE_ROOT,
node
);
}
/**
* @dev Base monster burning function
* @param _tokenId Monster token ID to burn
*/
function _burn(
uint256 _tokenId
)
internal
override
{
require(
_isApprovedOrOwner(_msgSender(), _tokenId) == true,
"not owner nor approved"
);
unchecked {
totalSupply -= 1;
}
super._burn(
_tokenId
);
}
/**
* @dev Base URI for computing tokenURI
* @return Base URI string
*/
function _baseURI()
internal
view
override
returns (string memory)
{
return baseURI;
}
/**
* @dev Base monster minting function, calculates price with discounts
* @param _numberOfTokens Number of monster tokens to mint
* @param _satsForDiscount Array of Satoshible IDs for discounted mints
*/
function _doMintTokens(
uint256 _numberOfTokens,
uint256[] calldata _satsForDiscount
)
private
{
require(
saleIsActive == true,
"Sale must be active"
);
require(
_numberOfTokens >= 1,
"Need at least 1 token"
);
require(
_numberOfTokens <= 50,
"Max 50 at a time"
);
require(
_satsForDiscount.length <= _numberOfTokens,
"Too many sats for discount"
);
unchecked {
uint256 discountIndex;
for (; discountIndex < _satsForDiscount.length; discountIndex++) {
_useSatForDiscountMint(_satsForDiscount[discountIndex]);
}
uint256 totalPrice = tokenPrice * (_numberOfTokens - discountIndex)
+ discountPrice * discountIndex;
require(
totalPrice == msg.value,
"Ether amount not correct"
);
}
_mintTokens(
_numberOfTokens
);
}
/**
* @dev Base monster minting function.
* @param _numberOfTokens Number of monster tokens to mint
*/
function _mintTokens(
uint256 _numberOfTokens
)
private
{
unchecked {
totalSupply += _numberOfTokens;
for (uint256 i = 0; i < _numberOfTokens; i++) {
monsterIds.increment();
_safeMint(
_msgSender(),
monsterIds.current()
);
}
}
}
/**
* @dev Marks a Satoshible ID as having been used for a discounted mint
* @param _satId Satoshible ID that was used for a discounted mint
*/
function _useSatForDiscountMint(
uint256 _satId
)
private
onlySatHolder(_satId)
{
require(
satIsAvailableForDiscountMint(_satId) == true,
"Sat for discount already used"
);
unchecked {
uint256 page = _satId / 256;
uint256 shift = _satId % 256;
satDiscountBitfields[page] &= ~(1 << shift);
}
}
/**
* @dev Marks a Satoshible ID as having been used to mint a prime
* @param _satId Satoshible ID that was used to mint a prime
*/
function _retireSatFromLab(
uint256 _satId
)
private
{
unchecked {
uint256 page = _satId / 256;
uint256 shift = _satId % 256;
satLabBitfields[page] &= ~(1 << shift);
}
}
/**
* @dev Initializes prime token ID offsets
*/
function _initializePrimeIdOffsets()
private
{
unchecked {
primeIdOffset[FRANKENSTEIN] = ALPHA;
primeIdOffset[WEREWOLF] = ALPHA + 166;
primeIdOffset[VAMPIRE] = ALPHA + 332;
primeIdOffset[ZOMBIE] = ALPHA + 498;
primeIdOffset[INVALID] = ALPHA + 665;
}
}
/**
* @dev Initializes bitfields of Satoshibles available for discounted mints
*/
function _initializeSatDiscountAvailability()
private
{
unchecked {
for (uint256 i = 0; i < 20; i++) {
satDiscountBitfields[i] = type(uint256).max;
}
}
}
/**
* @dev Initializes bitfields of Satoshibles available to mint primes
*/
function _initializeSatLabAvailability()
private
{
unchecked {
for (uint256 i = 0; i < 20; i++) {
satLabBitfields[i] = type(uint256).max;
}
}
}
/**
* @dev Helper function used for token ID range checks when minting
* @param _currentValue Current token ID counter value
* @param _incrementValue Number of tokens to increment by
* @param _maximumValue Maximum token ID value allowed
* @return isBelowMaximum True if _maximumValue is not exceeded
*/
function belowMaximum(
uint256 _currentValue,
uint256 _incrementValue,
uint256 _maximumValue
)
private
pure
returns (bool isBelowMaximum)
{
unchecked {
isBelowMaximum = _currentValue + _incrementValue <= _maximumValue;
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;
library MerkleProof {
function verify(
bytes32[] memory proof,
bytes32 root,
bytes32 leaf
)
internal
pure
returns (bool)
{
bytes32 computedHash = leaf;
for (uint256 i = 0; i < proof.length; i++) {
bytes32 proofElement = proof[i];
if (computedHash <= proofElement) {
computedHash = keccak256(abi.encodePacked(computedHash, proofElement));
} else {
computedHash = keccak256(abi.encodePacked(proofElement, computedHash));
}
}
return computedHash == root;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;
/// @title IERC2981Royalties
/// @dev Interface for the ERC2981 - Token Royalty standard
interface IERC2981Royalties {
/// @notice Called with the sale price to determine how much royalty
// is owed and to whom.
/// @param _tokenId - the NFT asset queried for royalty information
/// @param _value - the sale price of the NFT asset specified by _tokenId
/// @return _receiver - address of who should be sent the royalty payment
/// @return _royaltyAmount - the royalty payment amount for value sale price
function royaltyInfo(uint256 _tokenId, uint256 _value)
external
view
returns (address _receiver, uint256 _royaltyAmount);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;
import "@openzeppelin/contracts/utils/introspection/ERC165.sol";
import "./ERC2981Base.sol";
/// @dev This is a contract used to add ERC2981 support to ERC721 and 1155
/// @dev This implementation has the same royalties for each and every tokens
abstract contract ERC2981ContractWideRoyalties is ERC2981Base {
RoyaltyInfo private _royalties;
/// @dev Sets token royalties
/// @param _recipient recipient of the royalties
/// @param _value percentage (using 2 decimals - 10000 = 100, 0 = 0)
function _setRoyalties(
address _recipient,
uint256 _value
)
internal
{
require(_value <= 10000, "ERC2981Royalties: Too high");
_royalties = RoyaltyInfo(_recipient, uint24(_value));
}
/// @inheritdoc IERC2981Royalties
function royaltyInfo(
uint256,
uint256 _value
)
external
view
override
returns (address receiver, uint256 royaltyAmount)
{
RoyaltyInfo memory royalties = _royalties;
receiver = royalties.recipient;
royaltyAmount = (_value * royalties.amount) / 10000;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;
import "@openzeppelin/contracts/utils/introspection/ERC165.sol";
import "./IERC2981Royalties.sol";
/// @dev This is a contract used to add ERC2981 support to ERC721 and 1155
abstract contract ERC2981Base is ERC165, IERC2981Royalties {
struct RoyaltyInfo {
address recipient;
uint24 amount;
}
/// @inheritdoc ERC165
function supportsInterface(bytes4 interfaceId)
public
view
virtual
override
returns (bool)
{
return
interfaceId == type(IERC2981Royalties).interfaceId ||
super.supportsInterface(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
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 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;
/**
* @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 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;
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
assembly {
size := extcodesize(account)
}
return size > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value
) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
(bool success, bytes memory returndata) = target.call{value: value}(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(
address target,
bytes memory data,
string memory errorMessage
) internal view returns (bytes memory) {
require(isContract(target), "Address: static call to non-contract");
(bool success, bytes memory returndata) = target.staticcall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
require(isContract(target), "Address: delegate call to non-contract");
(bool success, bytes memory returndata) = target.delegatecall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason using the provided one.
*
* _Available since v4.3._
*/
function verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) internal pure returns (bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "../IERC721.sol";
/**
* @title ERC-721 Non-Fungible Token Standard, optional metadata extension
* @dev See https://eips.ethereum.org/EIPS/eip-721
*/
interface IERC721Metadata is IERC721 {
/**
* @dev Returns the token collection name.
*/
function name() external view returns (string memory);
/**
* @dev Returns the token collection symbol.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
*/
function tokenURI(uint256 tokenId) external view returns (string memory);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
* @title ERC721 token receiver interface
* @dev Interface for any contract that wants to support safeTransfers
* from ERC721 asset contracts.
*/
interface IERC721Receiver {
/**
* @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
* by `operator` from `from`, this function is called.
*
* It must return its Solidity selector to confirm the token transfer.
* If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
*
* The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.
*/
function onERC721Received(
address operator,
address from,
uint256 tokenId,
bytes calldata data
) external returns (bytes4);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
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;
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.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;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address recipient, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `sender` to `recipient` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(
address sender,
address recipient,
uint256 amount
) external returns (bool);
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: MIT
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() {
_setOwner(_msgSender());
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_setOwner(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
_setOwner(newOwner);
}
function _setOwner(address newOwner) private {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}