// SPDX-License-Identifier: AGPL-3.0-onlypragmasolidity >=0.8.0;/// @notice Modern, minimalist, and gas efficient ERC-721 implementation./// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC721.sol)abstractcontractERC721{
/*//////////////////////////////////////////////////////////////
EVENTS
//////////////////////////////////////////////////////////////*/eventTransfer(addressindexedfrom, addressindexed to, uint256indexed id);
eventApproval(addressindexed owner, addressindexed spender, uint256indexed id);
eventApprovalForAll(addressindexed owner, addressindexed operator, bool approved);
/*//////////////////////////////////////////////////////////////
METADATA STORAGE/LOGIC
//////////////////////////////////////////////////////////////*/stringpublic name;
stringpublic symbol;
functiontokenURI(uint256 id) publicviewvirtualreturns (stringmemory);
/*//////////////////////////////////////////////////////////////
ERC721 BALANCE/OWNER STORAGE
//////////////////////////////////////////////////////////////*/mapping(uint256=>address) internal _ownerOf;
mapping(address=>uint256) internal _balanceOf;
functionownerOf(uint256 id) publicviewvirtualreturns (address owner) {
require((owner = _ownerOf[id]) !=address(0), "NOT_MINTED");
}
functionbalanceOf(address owner) publicviewvirtualreturns (uint256) {
require(owner !=address(0), "ZERO_ADDRESS");
return _balanceOf[owner];
}
/*//////////////////////////////////////////////////////////////
ERC721 APPROVAL STORAGE
//////////////////////////////////////////////////////////////*/mapping(uint256=>address) public getApproved;
mapping(address=>mapping(address=>bool)) public isApprovedForAll;
/*//////////////////////////////////////////////////////////////
CONSTRUCTOR
//////////////////////////////////////////////////////////////*/constructor(stringmemory _name, stringmemory _symbol) {
name = _name;
symbol = _symbol;
}
/*//////////////////////////////////////////////////////////////
ERC721 LOGIC
//////////////////////////////////////////////////////////////*/functionapprove(address spender, uint256 id) publicvirtual{
address owner = _ownerOf[id];
require(msg.sender== owner || isApprovedForAll[owner][msg.sender], "NOT_AUTHORIZED");
getApproved[id] = spender;
emit Approval(owner, spender, id);
}
functionsetApprovalForAll(address operator, bool approved) publicvirtual{
isApprovedForAll[msg.sender][operator] = approved;
emit ApprovalForAll(msg.sender, operator, approved);
}
functiontransferFrom(addressfrom,
address to,
uint256 id
) publicvirtual{
require(from== _ownerOf[id], "WRONG_FROM");
require(to !=address(0), "INVALID_RECIPIENT");
require(
msg.sender==from|| isApprovedForAll[from][msg.sender] ||msg.sender== getApproved[id],
"NOT_AUTHORIZED"
);
// Underflow of the sender's balance is impossible because we check for// ownership above and the recipient's balance can't realistically overflow.unchecked {
_balanceOf[from]--;
_balanceOf[to]++;
}
_ownerOf[id] = to;
delete getApproved[id];
emit Transfer(from, to, id);
}
functionsafeTransferFrom(addressfrom,
address to,
uint256 id
) publicvirtual{
transferFrom(from, to, id);
require(
to.code.length==0||
ERC721TokenReceiver(to).onERC721Received(msg.sender, from, id, "") ==
ERC721TokenReceiver.onERC721Received.selector,
"UNSAFE_RECIPIENT"
);
}
functionsafeTransferFrom(addressfrom,
address to,
uint256 id,
bytescalldata data
) publicvirtual{
transferFrom(from, to, id);
require(
to.code.length==0||
ERC721TokenReceiver(to).onERC721Received(msg.sender, from, id, data) ==
ERC721TokenReceiver.onERC721Received.selector,
"UNSAFE_RECIPIENT"
);
}
/*//////////////////////////////////////////////////////////////
ERC165 LOGIC
//////////////////////////////////////////////////////////////*/functionsupportsInterface(bytes4 interfaceId) publicviewvirtualreturns (bool) {
return
interfaceId ==0x01ffc9a7||// ERC165 Interface ID for ERC165
interfaceId ==0x80ac58cd||// ERC165 Interface ID for ERC721
interfaceId ==0x5b5e139f; // ERC165 Interface ID for ERC721Metadata
}
/*//////////////////////////////////////////////////////////////
INTERNAL MINT/BURN LOGIC
//////////////////////////////////////////////////////////////*/function_mint(address to, uint256 id) internalvirtual{
require(to !=address(0), "INVALID_RECIPIENT");
require(_ownerOf[id] ==address(0), "ALREADY_MINTED");
// Counter overflow is incredibly unrealistic.unchecked {
_balanceOf[to]++;
}
_ownerOf[id] = to;
emit Transfer(address(0), to, id);
}
function_burn(uint256 id) internalvirtual{
address owner = _ownerOf[id];
require(owner !=address(0), "NOT_MINTED");
// Ownership check above ensures no underflow.unchecked {
_balanceOf[owner]--;
}
delete _ownerOf[id];
delete getApproved[id];
emit Transfer(owner, address(0), id);
}
/*//////////////////////////////////////////////////////////////
INTERNAL SAFE MINT LOGIC
//////////////////////////////////////////////////////////////*/function_safeMint(address to, uint256 id) internalvirtual{
_mint(to, id);
require(
to.code.length==0||
ERC721TokenReceiver(to).onERC721Received(msg.sender, address(0), id, "") ==
ERC721TokenReceiver.onERC721Received.selector,
"UNSAFE_RECIPIENT"
);
}
function_safeMint(address to,
uint256 id,
bytesmemory data
) internalvirtual{
_mint(to, id);
require(
to.code.length==0||
ERC721TokenReceiver(to).onERC721Received(msg.sender, address(0), id, data) ==
ERC721TokenReceiver.onERC721Received.selector,
"UNSAFE_RECIPIENT"
);
}
}
/// @notice A generic interface for a contract which properly accepts ERC721 tokens./// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC721.sol)abstractcontractERC721TokenReceiver{
functiononERC721Received(address,
address,
uint256,
bytescalldata) externalvirtualreturns (bytes4) {
return ERC721TokenReceiver.onERC721Received.selector;
}
}
Contract Source Code
File 2 of 5: Math.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.7.0) (utils/math/Math.sol)pragmasolidity >=0.8.17;/**
* @dev Standard math utilities missing in the Solidity language.
*/libraryMath{
/**
* @dev Return the log in base 10, rounded down, of a positive value.
* Returns 0 if given 0.
*/functionlog10(uint256 value) internalpurereturns (uint256) {
uint256 result =0;
unchecked {
if (value >=10**64) {
value /=10**64;
result +=64;
}
if (value >=10**32) {
value /=10**32;
result +=32;
}
if (value >=10**16) {
value /=10**16;
result +=16;
}
if (value >=10**8) {
value /=10**8;
result +=8;
}
if (value >=10**4) {
value /=10**4;
result +=4;
}
if (value >=10**2) {
value /=10**2;
result +=2;
}
if (value >=10**1) {
result +=1;
}
}
return result;
}
}