Contract Source Code:
// SPDX-License-Identifier: MIT LICENSE
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/security/Pausable.sol";
import "./Roar.sol";
import "@chainlink/contracts/src/v0.8/VRFConsumerBase.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "@openzeppelin/contracts/utils/Counters.sol";
import "@openzeppelin/contracts/utils/structs/EnumerableSet.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
interface ITSalmon {
function mint(address to, uint256 amount) external;
}
contract River is Ownable, IERC721Receiver, Pausable, VRFConsumerBase,ReentrancyGuard {
using Address for address;
using Counters for Counters.Counter;
using EnumerableSet for EnumerableSet.UintSet;
struct Stake {
uint16 tokenId;
uint80 value;
address owner;
}
/** INTERFACES */
Roar roar; // reference to the Roar NFT contract
ITSalmon salmon; // reference to the $SALMON contract for minting $SALMON earnings
event TokenStaked(address owner, uint256 tokenId, uint256 value);
event FishermanClaimed(uint256 tokenId, uint256 earned, bool unstaked);
event BearClaimed(uint256 tokenId, uint256 earned, bool unstaked);
mapping(uint256 => Stake) public riverside; // maps tokenId to stake
mapping(uint256 => Stake[]) public Bears; // maps alpha to all Bear stakes with that alpha
mapping(address => EnumerableSet.UintSet) private _deposits;
mapping(uint256 => uint256) public packIndices; // tracks location of each Bear in Pack
uint256 public totalAlphaStaked = 0; // total alpha scores staked
uint256 public unaccountedRewards = 0; // any rewards distributed when no bears are staked
uint256 public SalmonPerAlpha = 0; // amount of $SALMON due for each alpha point staked
uint256 public DAILY_SALMON_RATE = 10000 ether; // Fisherman earn 10000 $SALMON per day
uint256 public MINIMUM_TO_EXIT = 2 days; // Fisherman must have 2 days worth of $SALMON to unstake or else it's too cold
/** Constant Parameters*/
uint256 public constant SALMON_CLAIM_TAX_PERCENTAGE = 20; // Bears take a 20% tax on all $SALMON claimed
uint256 public constant MAXIMUM_GLOBAL_WOOL = 2400000000 ether; // there will only ever be (roughly) 2.4 billion $SALMON earned through staking
uint8 public constant MAX_ALPHA = 8;
uint256 public totalSalmonEarned; // amount of $SALMON earned so far
uint256 public totalFishermanStaked; // number of Fisherman staked in the Riverside
uint256 public lastClaimTimestamp; // the last time $SALMON was claimed
bool public rescueEnabled = false; // emergency rescue to allow unstaking without any checks but without $SALMON
//Chainlink Setup:
bytes32 internal keyHash;
uint256 public fee;
uint256 internal randomResult;
uint256 internal randomNumber;
address public linkToken;
uint256 public vrfcooldown = 10000;
Counters.Counter public vrfReqd;
constructor(address _roar, address _salmon, address _vrfCoordinator, address _link)
VRFConsumerBase(_vrfCoordinator, _link)
{
roar = Roar(_roar); // reference to the Roar NFT contract
salmon = ITSalmon(_salmon); //reference to the $SALMON token
keyHash = 0xAA77729D3466CA35AE8D28B3BBAC7CC36A5031EFDC430821C02BC31A238AF445;
fee = 2 * 10 ** 18; // 0.1 LINK (Varies by network)
linkToken = _link;
}
function depositsOf(address account) external view returns (uint256[] memory) {
EnumerableSet.UintSet storage depositSet = _deposits[account];
uint256[] memory tokenIds = new uint256[] (depositSet.length());
for (uint256 i; i < depositSet.length(); i++) {
tokenIds[i] = depositSet.at(i);
}
return tokenIds;
}
/** STAKING */
function addManyToRiverSideAndFishing(address account, uint16[] calldata tokenIds) external { // called in mint
require(account == _msgSender() || _msgSender() == address(roar), "DONT GIVE YOUR TOKENS AWAY"); /// SEE IF I CAN ADD THE MF CONTRACT BAN
for (uint i = 0; i < tokenIds.length; i++) {
if (_msgSender() != address(roar)) { // dont do this step if its a mint + stake
require(roar.ownerOf(tokenIds[i]) == _msgSender(), "AINT YO TOKEN");
roar.transferFrom(_msgSender(), address(this), tokenIds[i]);
} else if (tokenIds[i] == 0) {
continue; // there may be gaps in the array for stolen tokens
}
if (isFisherman(tokenIds[i]))
_addFishermanToRiverside(account, tokenIds[i]);
else
_sendBearsFishing(account, tokenIds[i]);
}
}
function _addFishermanToRiverside(address account, uint256 tokenId) internal whenNotPaused _updateEarnings {
riverside[tokenId] = Stake({
owner: account,
tokenId: uint16(tokenId),
value: uint80(block.timestamp)
});
totalFishermanStaked += 1;
emit TokenStaked(account, tokenId, block.timestamp);
_deposits[account].add(tokenId);
}
function _sendBearsFishing(address account, uint256 tokenId) internal {
uint256 alpha = _alphaForBear(tokenId);
totalAlphaStaked += alpha; // Portion of earnings ranges from 8 to 5
packIndices[tokenId] = Bears[alpha].length; // Store the location of the Bear in the Pack
Bears[alpha].push(Stake({ // Add the Bear to the Pack
owner: account,
tokenId: uint16(tokenId),
value: uint80(SalmonPerAlpha)
}));
emit TokenStaked(account, tokenId, SalmonPerAlpha);
_deposits[account].add(tokenId);
}
/** CLAIMING / UNSTAKING */
// realize $SALMON earnings and optionally unstake tokens from the RIVER / FISHING
function claimManyFromRiverAndFishing(uint16[] calldata tokenIds, bool unstake) external whenNotPaused _updateEarnings nonReentrant() {
require(!_msgSender().isContract(), "Contracts are not allowed big man");
uint256 owed = 0;
for (uint i = 0; i < tokenIds.length; i++) {
if (isFisherman(tokenIds[i]))
owed += _claimFisherFromRiver(tokenIds[i], unstake);
else
owed += _claimBearFromFishing(tokenIds[i], unstake);
}
if (owed == 0) return;
salmon.mint(_msgSender(), owed);
}
function calculateReward(uint16[] calldata tokenIds) public view returns (uint256 owed) {
for (uint i = 0; i < tokenIds.length; i++) {
if (isFisherman(tokenIds[i]))
owed += calcRewardFisherman(tokenIds[i]);
else
owed += calcRewardBear(tokenIds[i]);
}
}
function calcRewardFisherman(uint256 tokenId) public view returns (uint256 owed) {
Stake memory stake = riverside[tokenId];
if (totalSalmonEarned < MAXIMUM_GLOBAL_WOOL) {
owed = (block.timestamp - stake.value) * DAILY_SALMON_RATE / 1 days;
} else if (stake.value > lastClaimTimestamp) {
owed = 0; // $WOOL production stopped already
} else {
owed = (lastClaimTimestamp - stake.value) * DAILY_SALMON_RATE / 1 days; // stop earning additional $WOOL if it's all been earned
}
}
function calcRewardBear(uint256 tokenId) public view returns (uint256 owed) {
uint256 alpha = _alphaForBear(tokenId);
Stake memory stake = Bears[alpha][packIndices[tokenId]];
owed = (alpha) * (SalmonPerAlpha - stake.value);
// Calculate portion of tokens based on Alpha
}
// Basically, withdraws $SALMON earnings for a single Fisherman and optionally unstake it.
// 20% Bear Tax, 50% chance all goes to Bear if unstaking.
function _claimFisherFromRiver(uint256 tokenId, bool unstake) internal returns (uint256 owed) {
Stake memory stake = riverside[tokenId];
require(stake.owner == _msgSender(), "SWIPER, NO SWIPING");
require(!(unstake && block.timestamp - stake.value < MINIMUM_TO_EXIT), "GONNA BE COLD WITHOUT TWO DAY'S WOOL");
owed = calcRewardFisherman(tokenId);
if (unstake) {
getRandomChainlink();
if (random(tokenId) & 1 == 1) { // 50% chance of all $SALMON stolen
_payBearTax(owed);
owed = 0;
}
delete riverside[tokenId];
totalFishermanStaked -= 1;
_deposits[_msgSender()].remove(tokenId);
roar.safeTransferFrom(address(this), _msgSender(), tokenId, ""); // send back Fisherman
} else {
_payBearTax(owed * SALMON_CLAIM_TAX_PERCENTAGE / 100); // percentage tax to staked Bears
riverside[tokenId] = Stake({
owner: _msgSender(),
tokenId: uint16(tokenId),
value: uint80(block.timestamp)
}); // reset stake
owed = owed * (100 - SALMON_CLAIM_TAX_PERCENTAGE) / 100; // remainder goes to Fisherman owner
}
emit FishermanClaimed(tokenId, owed, unstake);
}
// Basically, withdraws $SALMON earnings for a single BEAR and optionally unstake it.
function _claimBearFromFishing(uint256 tokenId, bool unstake) internal returns (uint256 owed) {
uint256 alpha = _alphaForBear(tokenId);
Stake memory stake = Bears[alpha][packIndices[tokenId]];
require(roar.ownerOf(tokenId) == address(this), "AINT A PART OF THE PACK");
require(stake.owner == _msgSender(), "SWIPER, NO SWIPING");
owed = calcRewardBear(tokenId); // Calculate portion of tokens based on Alpha
if (unstake) {
totalAlphaStaked -= alpha; // Remove Alpha from total staked
Stake memory lastStake = Bears[alpha][Bears[alpha].length - 1]; // Shuffle last Bear to current position PT 1
Bears[alpha][packIndices[tokenId]] = lastStake; // Shuffle last Bear to current position PT 2
packIndices[lastStake.tokenId] = packIndices[tokenId]; // Shuffle last Bear to current position PT 3
Bears[alpha].pop(); // Remove duplicate
delete packIndices[tokenId]; // Delete old mapping
_deposits[_msgSender()].remove(tokenId);
roar.safeTransferFrom(address(this), _msgSender(), tokenId, ""); // Send back Bear
} else {
Bears[alpha][packIndices[tokenId]] = Stake({
owner: _msgSender(),
tokenId: uint16(tokenId),
value: uint80(SalmonPerAlpha)
}); // reset stake
}
emit BearClaimed(tokenId, owed, unstake);
}
// emergency unstake tokens
function rescue(uint256[] calldata tokenIds) external nonReentrant() {
require(!_msgSender().isContract(), "Contracts are not allowed big man");
require(rescueEnabled, "RESCUE DISABLED");
uint256 tokenId;
Stake memory stake;
Stake memory lastStake;
uint256 alpha;
for (uint i = 0; i < tokenIds.length; i++) {
tokenId = tokenIds[i];
if (isFisherman(tokenId)) {
stake = riverside[tokenId];
require(stake.owner == _msgSender(), "SWIPER, NO SWIPING");
delete riverside[tokenId];
totalFishermanStaked -= 1;
roar.safeTransferFrom(address(this), _msgSender(), tokenId, ""); // send back Fisherman
emit FishermanClaimed(tokenId, 0, true);
} else {
alpha = _alphaForBear(tokenId);
stake = Bears[alpha][packIndices[tokenId]];
require(stake.owner == _msgSender(), "SWIPER, NO SWIPING");
totalAlphaStaked -= alpha; // Remove Alpha from total staked
lastStake = Bears[alpha][Bears[alpha].length - 1];
Bears[alpha][packIndices[tokenId]] = lastStake; // Shuffle last bear to current position
packIndices[lastStake.tokenId] = packIndices[tokenId];
Bears[alpha].pop(); // Remove duplicate
delete packIndices[tokenId]; // Delete old mapping
roar.safeTransferFrom(address(this), _msgSender(), tokenId, ""); // Send back Fisherman
emit BearClaimed(tokenId, 0, true);
}
}
}
/** ACCOUNTING */
// add $SALMON to claimable pot for the Pack
function _payBearTax(uint256 amount) internal {
if (totalAlphaStaked == 0) { // if there's no staked Bear > keep track of $SALMON due to Bear
unaccountedRewards += amount;
return;
}
SalmonPerAlpha += (amount + unaccountedRewards) / totalAlphaStaked; // makes sure to include any unaccounted $SALMON
unaccountedRewards = 0;
}
// tracks $SALMIN earnings to ensure it stops once 2.4 billion is eclipsed
modifier _updateEarnings() {
if (totalSalmonEarned < MAXIMUM_GLOBAL_WOOL) {
totalSalmonEarned +=
(block.timestamp - lastClaimTimestamp)
* totalFishermanStaked
* DAILY_SALMON_RATE / 1 days;
lastClaimTimestamp = block.timestamp;
}
_;
}
function isFisherman(uint256 tokenId) public view returns (bool fisherman) {
// SheepWolf memory t = roar.getTokenTraits(tokenId);(sheep, , , , , , , , , ) = roar.tokenTraits(tokenId);
(fisherman, ) = roar.tokenTraits(tokenId);
}
// gets the alpha score for a Bear
function _alphaForBear(uint256 tokenId) public view returns (uint8) {
( ,uint8 alphaIndex) = roar.tokenTraits(tokenId);
return MAX_ALPHA - alphaIndex; // alpha index is 0-3
}
// chooses a random Bear thief when a newly minted token is stolen
function randomBearOwner(uint256 seed) external view returns (address) {
if (totalAlphaStaked == 0) return address(0x0);
uint256 bucket = (seed & 0xFFFFFFFF) % totalAlphaStaked; // choose a value from 0 to total alpha staked
uint256 cumulative;
seed >>= 32;
for (uint i = MAX_ALPHA - 3; i <= MAX_ALPHA; i++) { // loop through each bucket of Bears with the same alpha score
cumulative += Bears[i].length * i;
if (bucket >= cumulative) continue; // if the value is not inside of that bucket, keep going
return Bears[i][seed % Bears[i].length].owner; // get the address of a random Bear with that alpha score
}
return address(0x0);
}
/** CHANGE PARAMETERS */
function setInit(address _roar, address _salmon) external onlyOwner{
roar = Roar(_roar); // reference to the Roar NFT contract
salmon = ITSalmon(_salmon); //reference to the $SALMON token
}
function changeDailyRate(uint256 _newRate) external onlyOwner{
DAILY_SALMON_RATE = _newRate;
}
function changeMinExit(uint256 _newExit) external onlyOwner{
_newExit = _newExit ;
}
function setRescueEnabled(bool _enabled) external onlyOwner {
rescueEnabled = _enabled;
}
function setPaused(bool _paused) external onlyOwner {
if (_paused) _pause();
else _unpause();
}
/** RANDOMNESSSS */
function changeLinkFee(uint256 _fee) external onlyOwner {
// fee = 0.1 * 10 ** 18; // 0.1 LINK (Varies by network)
fee = _fee;
}
function random(uint256 seed) internal view returns (uint256) {
return uint256(keccak256(abi.encodePacked(
tx.origin,
blockhash(block.number - 1),
block.timestamp,
seed,
randomNumber
)));
}
function initChainLink() external onlyOwner {
getRandomChainlink();
}
function getRandomChainlink() internal returns (bytes32 requestId) {
if (vrfReqd.current() <= vrfcooldown) {
vrfReqd.increment();
return 0x000;
}
require(LINK.balanceOf(address(this)) >= fee, "Not enough LINK - fill contract with faucet");
vrfReqd.reset();
return requestRandomness(keyHash, fee);
}
function changeVrfCooldown(uint256 _cooldown) external onlyOwner{
vrfcooldown = _cooldown;
}
function fulfillRandomness(bytes32 requestId, uint256 randomness) internal override {
bytes32 reqId = requestId;
randomNumber = randomness;
}
function withdrawLINK() external onlyOwner {
uint256 tokenSupply = IERC20(linkToken).balanceOf(address(this));
IERC20(linkToken).transfer(msg.sender, tokenSupply);
}
/** OTHERS */
function onERC721Received(address, address from, uint256, bytes calldata) external pure override returns (bytes4) {
require(from == address(0x0), "Cannot send tokens to Barn directly");
return IERC721Receiver.onERC721Received.selector;
}
}
// SPDX-License-Identifier: MIT LICENSE
pragma solidity ^0.8.7;
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/security/Pausable.sol";
import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol";
import "@chainlink/contracts/src/v0.8/VRFConsumerBase.sol";
import "@openzeppelin/contracts/utils/Counters.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/utils/structs/EnumerableSet.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
interface ISalmon {
function burn(address from, uint256 amount) external;
}
interface ITraits {
function tokenURI(uint256 tokenId) external view returns (string memory);
}
interface IRoar {
struct ManBear {bool isFisherman; uint8[14] traitarray; uint8 alphaIndex;}
function getPaidTokens() external view returns (uint256);
function getTokenTraits(uint256 tokenId) external view returns (ManBear memory);
}
interface IRiver {
function addManyToRiverSideAndFishing(address account, uint16[] calldata tokenIds) external;
function randomBearOwner(uint256 seed) external view returns (address);
}
contract Roar is IRoar, ERC721Enumerable, Ownable, Pausable, VRFConsumerBase {
using Counters for Counters.Counter;
using EnumerableSet for EnumerableSet.UintSet;
// mint variables
uint256 public immutable MAX_TOKENS; // max number of tokens that can be minted - 50000 in production
uint256 public PAID_TOKENS; // number of tokens that can be claimed for free - 20% of MAX_TOKENS
uint16 public minted; // number of tokens have been minted so far
uint256 public constant MINT_PRICE = .069420 ether; // mint price
string public baseURI;
// mappings
mapping(address => uint256) public whitelists;
mapping(uint256 => ManBear) public tokenTraits; // mapping from tokenId to a struct containing the token's traits
mapping(uint256 => uint256) public existingCombinations; // mapping from hashed(tokenTrait) to the tokenId it's associated with, Why? used to ensure there are no duplicates
mapping(address => uint256[]) public _mints;
// Pobabilities & Aliases
// 0 - 8 are associated with fishermen, 9 - 13 are associated with Bears
uint8[][18] public rarities;
uint8[][18] public aliases;
IRiver public river; // STAKING - reference to the Barn for choosing random Bear thieves
ISalmon public salmon; // TOKEN - reference to $WOOL for burning on mint
ITraits public traits; // TRAITS - reference to Traits
// Team Wallets
address private project_wallet = 0x06e8198A5a4AB3E5F4B13DdC9e5c2FCDDD4f8838;
address private Bear1 = 0x9E4FaAA4EFd0fb8CbC653Ee68C01c066d078098D;
address private Bear2 = 0xe18195D4995D994fAa3663db0b6E2FFF4042D0a1;
address private Bear3 = 0x9c39cD2f557B5E851f44ab18714BbBB15FA7417E;
address private Bear4 = 0x24af21668F33C8C279025b0E53fCC3bFf48426A0;
//Chainlink Setup:
bytes32 internal keyHash;
uint256 public fee;
uint256 internal randomResult;
uint256 internal randomNumber;
address public linkToken;
uint256 public vrfcooldown = 10000;
Counters.Counter public vrfReqd;
constructor(address _salmon, uint256 _maxTokens, address _vrfCoordinator, address _link)
ERC721("BearGame", 'BEARGAME')
VRFConsumerBase(_vrfCoordinator, _link)
{
keyHash = 0xAA77729D3466CA35AE8D28B3BBAC7CC36A5031EFDC430821C02BC31A238AF445;
fee = 2 * 10 ** 18; // 0.1 LINK (Varies by network)
linkToken = _link;
// Initate Interfaces
salmon = ISalmon(_salmon);
MAX_TOKENS = _maxTokens;
PAID_TOKENS = _maxTokens / 5;
// string[13] _traitTypes = ['Hat','Eyes','Body','Pants','Skintone','Mouth','Feet','Fishing Pole','Fish','Fur','Eyes','Clothes','Mouth','Alpha'];
rarities[0] = [31,49,51,69,113,187,204,207,225];
rarities[1] = [35,48,67,115,189,208,221];
rarities[2] = [59,97,136,159,197];
rarities[3] = [85,113,131,143,169];
rarities[4] = [255,255,255,255];
rarities[5] = [34,59,118,164,197,222];
rarities[6] = [59,111,145,197];
rarities[7] = [57,93,163,199];
rarities[8] = [255];
aliases[0] = [8,7,6,5,4,3,2,1,0];
aliases[1] = [6,5,4,3,2,1,0];
aliases[2] = [4,3,2,1,0];
aliases[3] = [4,3,2,1,0];
aliases[4] = [3,2,1,0];
aliases[5] = [5,4,3,2,1,0];
aliases[6] = [3,2,1,0];
aliases[7] = [3,2,1,0];
aliases[8] = [0];
rarities[9] = [255,255,255,255,255];
rarities[10] = [39,51,59,67,125,131,189,197,204,217];
rarities[11] = [51,54,57,64,72,90,194,199,202,207,212];
rarities[12] = [48,60,96,160,196,208];
rarities[13] = [51,102,153,204];
aliases[9] = [0,1,2,3,4];
aliases[10] = [9,8,7,6,5,4,3,2,1,0];
aliases[11] = [10,9,8,7,6,5,4,3,2,1,0];
aliases[12] = [5,4,3,2,1,0];
aliases[13] = [3,2,1,0];
}
/**
* mint a token - 90% Bears, 10% Fisherman
* The first 20% are free to claim, the remaining cost $SALMON
*/
// Calculates Mint Cost using $SALMON
function mintCost(uint256 tokenId) public view returns (uint256) {
if (tokenId <= PAID_TOKENS) return 0; // the first 20% are paid in ETH, Hence 0 $SALMON
if (tokenId <= MAX_TOKENS * 2 / 5) return 20000 ether; // the next 20% are 20000 $SALMON
if (tokenId <= MAX_TOKENS * 4 / 5) return 40000 ether; // the next 40% are 40000 $SALMON
return 80000 ether; // the final 20% are 80000 $SALMON
}
// Main Mint Functions
function mint(uint256 amount, bool stake) external payable whenNotPaused {
address msgSender = _msgSender();
require(tx.origin == msgSender, "Only EOA");
require(minted + amount <= MAX_TOKENS, "All tokens minted");
require(amount > 0 && amount <= 10, "Invalid mint amount");
if (minted < PAID_TOKENS) {
uint256 mintCostEther = MINT_PRICE * amount;
if (whitelists[msgSender] == 1) {
mintCostEther = ( amount - 1) * MINT_PRICE;
whitelists[msgSender] = 0;
}
require(minted + amount <= PAID_TOKENS, "All tokens on-sale already sold");
require(mintCostEther == msg.value, "Invalid payment amount");
} else {
require(msg.value == 0);
}
uint256 totalSalmonCost = 0; // $SALMON Cost to mint. 0 is Gen0
uint16[] memory tokenIds = stake ? new uint16[](amount) : new uint16[](0);
uint256 seed;
for (uint i = 0; i < amount; i++) {
minted++;
seed = random(minted); // NOTES: SUS
generate(minted, seed); // Generates Token Traits and adds it to the array
address recipient = selectRecipient(seed); // Selects who the NFT is going to. Gen0 always will be minter.
if (!stake || recipient != msgSender) { // recipient != _msgSender() -- IF I BAN CONTRACT, SHIT MIGHT BE GOOOOOFY
_safeMint(recipient, minted);
} else {
_safeMint(address(river), minted);
tokenIds[i] = minted;
}
totalSalmonCost += mintCost(minted);
}
if (totalSalmonCost > 0) salmon.burn(msgSender, totalSalmonCost);
if (stake) river.addManyToRiverSideAndFishing(msgSender, tokenIds);
}
function transferFrom(
address from,
address to,
uint256 tokenId
) public virtual override {
// Hardcode the River's approval so that users don't have to waste gas approving
if (_msgSender() != address(river))
require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
_transfer(from, to, tokenId);
}
// generates traits for a specific token, checking to make sure it's unique
function generate(uint256 tokenId, uint256 seed) internal returns (ManBear memory t) {
getRandomChainlink();
t = selectTraits(seed);
if (existingCombinations[structToHash(t.isFisherman, t.traitarray, t.alphaIndex)] == 0) {
tokenTraits[tokenId] = t;
existingCombinations[structToHash(t.isFisherman, t.traitarray, t.alphaIndex)] = tokenId;
return t;
}
return generate(tokenId, random(seed));
}
// Selects Trait using A.J. Walker's Alias algorithm for O(1) rarity table lookup
function selectTrait(uint16 seed, uint8 traitType) internal view returns (uint8) {
uint8 trait = uint8(seed) % uint8(rarities[traitType].length);
if (seed >> 8 < rarities[traitType][trait]) return trait;
return aliases[traitType][trait];
}
// selects the species and all of its traits based on the seed value
function selectTraits(uint256 seed) internal view returns (ManBear memory t) {
t.isFisherman = (seed & 0xFFFF) % 10 != 0;
uint8 shift = t.isFisherman ? 0 : 9; // 0 if its a Fisherman, 9 if its Bear
seed >>= 16;
if (t.isFisherman) {
// / 0 - 8 are associated with fishermen,
t.traitarray[0] = selectTrait(uint16(seed & 0xFFFF), 0 + shift);
seed >>= 16;
t.traitarray[1] = selectTrait(uint16(seed & 0xFFFF), 1 + shift);
seed >>= 16;
t.traitarray[2] = selectTrait(uint16(seed & 0xFFFF), 2 + shift);
seed >>= 16;
t.traitarray[3] = selectTrait(uint16(seed & 0xFFFF), 3 + shift);
seed >>= 16;
t.traitarray[4] = selectTrait(uint16(seed & 0xFFFF), 4 + shift);
seed >>= 16;
t.traitarray[5] = selectTrait(uint16(seed & 0xFFFF), 5 + shift);
seed >>= 16;
t.traitarray[6] = selectTrait(uint16(seed & 0xFFFF), 6 + shift);
seed >>= 16;
t.traitarray[7] = selectTrait(uint16(seed & 0xFFFF), 7 + shift);
seed >>= 16;
t.traitarray[8] = selectTrait(uint16(seed & 0xFFFF), 8 + shift);
t.alphaIndex = 0;
} else {
// 9 - 13 are associated with Bears
t.traitarray[9] = selectTrait(uint16(seed & 0xFFFF), 0 + shift);
seed >>= 16;
t.traitarray[10] = selectTrait(uint16(seed & 0xFFFF), 1 + shift);
seed >>= 16;
t.traitarray[11] = selectTrait(uint16(seed & 0xFFFF), 2 + shift);
seed >>= 16;
t.traitarray[12] = selectTrait(uint16(seed & 0xFFFF), 3 + shift);
seed >>= 16;
t.traitarray[13] = selectTrait(uint16(seed & 0xFFFF), 4 + shift);
t.alphaIndex = t.traitarray[13];
}
}
// converts a struct to a 256 bit hash to check for uniqueness
function structToHash(bool isFisherman, uint8[14] memory traitarray, uint8 alphaIndex) internal pure returns (uint256) {
if(isFisherman){
return uint256(bytes32(abi.encodePacked(true,
traitarray[0],
traitarray[1],
traitarray[2],
traitarray[3],
traitarray[4],
traitarray[5],
traitarray[6],
traitarray[7],
traitarray[8],
"0",
"0",
"0",
"0",
"0",
alphaIndex)));
}
else{
return uint256(bytes32(abi.encodePacked(false,
"0",
"0",
"0",
"0",
"0",
"0",
"0",
"0",
"0",
traitarray[9],
traitarray[10],
traitarray[11],
traitarray[12],
traitarray[13],
alphaIndex)));
}
}
// Select who the NFT goes to --- The first 20% (ETH purchases) go to the minter & the remaining 80% have a 10% chance to be given to a random staked Bear
function selectRecipient(uint256 seed) internal view returns (address) {
if (minted <= PAID_TOKENS || ((seed >> 245) % 10) != 0) return _msgSender(); // top 10 bits haven't been used
address thief = river.randomBearOwner(seed >> 144); // 144 bits reserved for trait selection
if (thief == address(0x0)) return _msgSender();
return thief;
}
/** READ */
function getTokenTraits(uint256 tokenId) external view override returns (ManBear memory) {
return tokenTraits[tokenId];
}
function getPaidTokens() external view override returns (uint256) {
return PAID_TOKENS;
}
// called after deployment so that the contract can get random Bear thieves
function setRiver(address _river) external onlyOwner {
river = IRiver(_river);
getRandomChainlink();
}
// Set Interfaces
function setInit(address _river, address erc20Address, address _traits ) public onlyOwner {
river = IRiver(_river);
salmon = ISalmon(erc20Address);
// salmon = IERC20(_salmon);
traits = ITraits(_traits);
getRandomChainlink();
}
// Set Base URL
function setURI(string memory _newBaseURI) external onlyOwner {
baseURI = _newBaseURI;
}
// withdraw functions
function withdraw() public payable onlyOwner {
uint256 _project = (address(this).balance * 10) / 100;
uint256 _bear1 = (address(this).balance * 225) / 1000;
uint256 _bear2 = (address(this).balance * 225) / 1000;
uint256 _bear3 = (address(this).balance * 225) / 1000;
uint256 _bear4 = (address(this).balance * 225) / 1000;
payable(project_wallet).transfer(_project);
payable(Bear1).transfer(_bear1);
payable(Bear2).transfer(_bear2);
payable(Bear3).transfer(_bear3);
payable(Bear4).transfer(_bear4);
}
// updates the number of tokens for sale
function setPaidTokens(uint256 _paidTokens) external onlyOwner {
PAID_TOKENS = _paidTokens;
// MAX_TOKENS = _maxTokens;
// PAID_TOKENS = _maxTokens / 5;
}
// enables owner to pause / unpause minting
function setPaused(bool _paused) external onlyOwner {
if (_paused) _pause();
else _unpause();
}
function addWhitelist(address[] calldata addressArrays) external onlyOwner {
uint256 addylength = addressArrays.length;
for (uint256 i; i < addylength; i++ ){
whitelists[addressArrays[i]] = 1;
}
}
/** RENDER */
function setBaseURI(string memory newUri) public onlyOwner {
baseURI = newUri;
}
function _baseURI() internal view virtual override returns (string memory) {
return baseURI;
}
function getTokenIds(address _owner) public view returns (uint256[] memory _tokensOfOwner) {
_tokensOfOwner = new uint256[](balanceOf(_owner));
for (uint256 i;i<balanceOf(_owner);i++){
_tokensOfOwner[i] = tokenOfOwnerByIndex(_owner, i);
}
}
/** RANDOMNESSSS */
function random(uint256 seed) internal view returns (uint256) {
return uint256(keccak256(abi.encodePacked(
tx.origin,
blockhash(block.number - 1),
block.timestamp,
seed,
randomNumber
)));
}
function changeLinkFee(uint256 _fee) external onlyOwner {
// fee = 0.1 * 10 ** 18; // 0.1 LINK (Varies by network)
fee = _fee;
}
function initChainLink() external onlyOwner {
getRandomChainlink();
}
function getRandomChainlink() internal returns (bytes32 requestId) {
if (vrfReqd.current() <= vrfcooldown) {
vrfReqd.increment();
return 0x000;
}
require(LINK.balanceOf(address(this)) >= fee, "Not enough LINK - fill contract with faucet");
vrfReqd.reset();
return requestRandomness(keyHash, fee);
}
function changeVrfCooldown(uint256 _cooldown) external onlyOwner{
vrfcooldown = _cooldown;
}
function fulfillRandomness(bytes32 requestId, uint256 randomness) internal override {
bytes32 reqId = requestId;
randomNumber = randomness;
}
function withdrawLINK() external onlyOwner {
uint256 tokenSupply = IERC20(linkToken).balanceOf(address(this));
IERC20(linkToken).transfer(msg.sender, tokenSupply);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
* @dev Library for managing
* https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
* types.
*
* Sets have the following properties:
*
* - Elements are added, removed, and checked for existence in constant time
* (O(1)).
* - Elements are enumerated in O(n). No guarantees are made on the ordering.
*
* ```
* contract Example {
* // Add the library methods
* using EnumerableSet for EnumerableSet.AddressSet;
*
* // Declare a set state variable
* EnumerableSet.AddressSet private mySet;
* }
* ```
*
* As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
* and `uint256` (`UintSet`) are supported.
*/
library EnumerableSet {
// To implement this library for multiple types with as little code
// repetition as possible, we write it in terms of a generic Set type with
// bytes32 values.
// The Set implementation uses private functions, and user-facing
// implementations (such as AddressSet) are just wrappers around the
// underlying Set.
// This means that we can only create new EnumerableSets for types that fit
// in bytes32.
struct Set {
// Storage of set values
bytes32[] _values;
// Position of the value in the `values` array, plus 1 because index 0
// means a value is not in the set.
mapping(bytes32 => uint256) _indexes;
}
/**
* @dev Add a value to a set. O(1).
*
* Returns true if the value was added to the set, that is if it was not
* already present.
*/
function _add(Set storage set, bytes32 value) private returns (bool) {
if (!_contains(set, value)) {
set._values.push(value);
// The value is stored at length-1, but we add 1 to all indexes
// and use 0 as a sentinel value
set._indexes[value] = set._values.length;
return true;
} else {
return false;
}
}
/**
* @dev Removes a value from a set. O(1).
*
* Returns true if the value was removed from the set, that is if it was
* present.
*/
function _remove(Set storage set, bytes32 value) private returns (bool) {
// We read and store the value's index to prevent multiple reads from the same storage slot
uint256 valueIndex = set._indexes[value];
if (valueIndex != 0) {
// Equivalent to contains(set, value)
// To delete an element from the _values array in O(1), we swap the element to delete with the last one in
// the array, and then remove the last element (sometimes called as 'swap and pop').
// This modifies the order of the array, as noted in {at}.
uint256 toDeleteIndex = valueIndex - 1;
uint256 lastIndex = set._values.length - 1;
if (lastIndex != toDeleteIndex) {
bytes32 lastvalue = set._values[lastIndex];
// Move the last value to the index where the value to delete is
set._values[toDeleteIndex] = lastvalue;
// Update the index for the moved value
set._indexes[lastvalue] = valueIndex; // Replace lastvalue's index to valueIndex
}
// Delete the slot where the moved value was stored
set._values.pop();
// Delete the index for the deleted slot
delete set._indexes[value];
return true;
} else {
return false;
}
}
/**
* @dev Returns true if the value is in the set. O(1).
*/
function _contains(Set storage set, bytes32 value) private view returns (bool) {
return set._indexes[value] != 0;
}
/**
* @dev Returns the number of values on the set. O(1).
*/
function _length(Set storage set) private view returns (uint256) {
return set._values.length;
}
/**
* @dev Returns the value stored at position `index` in the set. O(1).
*
* Note that there are no guarantees on the ordering of values inside the
* array, and it may change when more values are added or removed.
*
* Requirements:
*
* - `index` must be strictly less than {length}.
*/
function _at(Set storage set, uint256 index) private view returns (bytes32) {
return set._values[index];
}
/**
* @dev Return the entire set in an array
*
* WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
* to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
* this function has an unbounded cost, and using it as part of a state-changing function may render the function
* uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
*/
function _values(Set storage set) private view returns (bytes32[] memory) {
return set._values;
}
// Bytes32Set
struct Bytes32Set {
Set _inner;
}
/**
* @dev Add a value to a set. O(1).
*
* Returns true if the value was added to the set, that is if it was not
* already present.
*/
function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
return _add(set._inner, value);
}
/**
* @dev Removes a value from a set. O(1).
*
* Returns true if the value was removed from the set, that is if it was
* present.
*/
function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
return _remove(set._inner, value);
}
/**
* @dev Returns true if the value is in the set. O(1).
*/
function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
return _contains(set._inner, value);
}
/**
* @dev Returns the number of values in the set. O(1).
*/
function length(Bytes32Set storage set) internal view returns (uint256) {
return _length(set._inner);
}
/**
* @dev Returns the value stored at position `index` in the set. O(1).
*
* Note that there are no guarantees on the ordering of values inside the
* array, and it may change when more values are added or removed.
*
* Requirements:
*
* - `index` must be strictly less than {length}.
*/
function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
return _at(set._inner, index);
}
/**
* @dev Return the entire set in an array
*
* WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
* to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
* this function has an unbounded cost, and using it as part of a state-changing function may render the function
* uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
*/
function values(Bytes32Set storage set) internal view returns (bytes32[] memory) {
return _values(set._inner);
}
// AddressSet
struct AddressSet {
Set _inner;
}
/**
* @dev Add a value to a set. O(1).
*
* Returns true if the value was added to the set, that is if it was not
* already present.
*/
function add(AddressSet storage set, address value) internal returns (bool) {
return _add(set._inner, bytes32(uint256(uint160(value))));
}
/**
* @dev Removes a value from a set. O(1).
*
* Returns true if the value was removed from the set, that is if it was
* present.
*/
function remove(AddressSet storage set, address value) internal returns (bool) {
return _remove(set._inner, bytes32(uint256(uint160(value))));
}
/**
* @dev Returns true if the value is in the set. O(1).
*/
function contains(AddressSet storage set, address value) internal view returns (bool) {
return _contains(set._inner, bytes32(uint256(uint160(value))));
}
/**
* @dev Returns the number of values in the set. O(1).
*/
function length(AddressSet storage set) internal view returns (uint256) {
return _length(set._inner);
}
/**
* @dev Returns the value stored at position `index` in the set. O(1).
*
* Note that there are no guarantees on the ordering of values inside the
* array, and it may change when more values are added or removed.
*
* Requirements:
*
* - `index` must be strictly less than {length}.
*/
function at(AddressSet storage set, uint256 index) internal view returns (address) {
return address(uint160(uint256(_at(set._inner, index))));
}
/**
* @dev Return the entire set in an array
*
* WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
* to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
* this function has an unbounded cost, and using it as part of a state-changing function may render the function
* uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
*/
function values(AddressSet storage set) internal view returns (address[] memory) {
bytes32[] memory store = _values(set._inner);
address[] memory result;
assembly {
result := store
}
return result;
}
// UintSet
struct UintSet {
Set _inner;
}
/**
* @dev Add a value to a set. O(1).
*
* Returns true if the value was added to the set, that is if it was not
* already present.
*/
function add(UintSet storage set, uint256 value) internal returns (bool) {
return _add(set._inner, bytes32(value));
}
/**
* @dev Removes a value from a set. O(1).
*
* Returns true if the value was removed from the set, that is if it was
* present.
*/
function remove(UintSet storage set, uint256 value) internal returns (bool) {
return _remove(set._inner, bytes32(value));
}
/**
* @dev Returns true if the value is in the set. O(1).
*/
function contains(UintSet storage set, uint256 value) internal view returns (bool) {
return _contains(set._inner, bytes32(value));
}
/**
* @dev Returns the number of values on the set. O(1).
*/
function length(UintSet storage set) internal view returns (uint256) {
return _length(set._inner);
}
/**
* @dev Returns the value stored at position `index` in the set. O(1).
*
* Note that there are no guarantees on the ordering of values inside the
* array, and it may change when more values are added or removed.
*
* Requirements:
*
* - `index` must be strictly less than {length}.
*/
function at(UintSet storage set, uint256 index) internal view returns (uint256) {
return uint256(_at(set._inner, index));
}
/**
* @dev Return the entire set in an array
*
* WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
* to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
* this function has an unbounded cost, and using it as part of a state-changing function may render the function
* uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
*/
function values(UintSet storage set) internal view returns (uint256[] memory) {
bytes32[] memory store = _values(set._inner);
uint256[] memory result;
assembly {
result := store
}
return result;
}
}
// 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;
import "../IERC721.sol";
/**
* @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
* @dev See https://eips.ethereum.org/EIPS/eip-721
*/
interface IERC721Enumerable is IERC721 {
/**
* @dev Returns the total amount of tokens stored by the contract.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns a token ID owned by `owner` at a given `index` of its token list.
* Use along with {balanceOf} to enumerate all of ``owner``'s tokens.
*/
function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256 tokenId);
/**
* @dev Returns a token ID at a given `index` of all the tokens stored by the contract.
* Use along with {totalSupply} to enumerate all tokens.
*/
function tokenByIndex(uint256 index) external view returns (uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "../ERC721.sol";
import "./IERC721Enumerable.sol";
/**
* @dev This implements an optional extension of {ERC721} defined in the EIP that adds
* enumerability of all the token ids in the contract as well as all token ids owned by each
* account.
*/
abstract contract ERC721Enumerable is ERC721, IERC721Enumerable {
// Mapping from owner to list of owned token IDs
mapping(address => mapping(uint256 => uint256)) private _ownedTokens;
// Mapping from token ID to index of the owner tokens list
mapping(uint256 => uint256) private _ownedTokensIndex;
// Array with all token ids, used for enumeration
uint256[] private _allTokens;
// Mapping from token id to position in the allTokens array
mapping(uint256 => uint256) private _allTokensIndex;
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC721) returns (bool) {
return interfaceId == type(IERC721Enumerable).interfaceId || super.supportsInterface(interfaceId);
}
/**
* @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
*/
function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual override returns (uint256) {
require(index < ERC721.balanceOf(owner), "ERC721Enumerable: owner index out of bounds");
return _ownedTokens[owner][index];
}
/**
* @dev See {IERC721Enumerable-totalSupply}.
*/
function totalSupply() public view virtual override returns (uint256) {
return _allTokens.length;
}
/**
* @dev See {IERC721Enumerable-tokenByIndex}.
*/
function tokenByIndex(uint256 index) public view virtual override returns (uint256) {
require(index < ERC721Enumerable.totalSupply(), "ERC721Enumerable: global index out of bounds");
return _allTokens[index];
}
/**
* @dev Hook that is called before any token transfer. This includes minting
* and burning.
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
* transferred to `to`.
* - When `from` is zero, `tokenId` will be minted for `to`.
* - When `to` is zero, ``from``'s `tokenId` will be burned.
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _beforeTokenTransfer(
address from,
address to,
uint256 tokenId
) internal virtual override {
super._beforeTokenTransfer(from, to, tokenId);
if (from == address(0)) {
_addTokenToAllTokensEnumeration(tokenId);
} else if (from != to) {
_removeTokenFromOwnerEnumeration(from, tokenId);
}
if (to == address(0)) {
_removeTokenFromAllTokensEnumeration(tokenId);
} else if (to != from) {
_addTokenToOwnerEnumeration(to, tokenId);
}
}
/**
* @dev Private function to add a token to this extension's ownership-tracking data structures.
* @param to address representing the new owner of the given token ID
* @param tokenId uint256 ID of the token to be added to the tokens list of the given address
*/
function _addTokenToOwnerEnumeration(address to, uint256 tokenId) private {
uint256 length = ERC721.balanceOf(to);
_ownedTokens[to][length] = tokenId;
_ownedTokensIndex[tokenId] = length;
}
/**
* @dev Private function to add a token to this extension's token tracking data structures.
* @param tokenId uint256 ID of the token to be added to the tokens list
*/
function _addTokenToAllTokensEnumeration(uint256 tokenId) private {
_allTokensIndex[tokenId] = _allTokens.length;
_allTokens.push(tokenId);
}
/**
* @dev Private function to remove a token from this extension's ownership-tracking data structures. Note that
* while the token is not assigned a new owner, the `_ownedTokensIndex` mapping is _not_ updated: this allows for
* gas optimizations e.g. when performing a transfer operation (avoiding double writes).
* This has O(1) time complexity, but alters the order of the _ownedTokens array.
* @param from address representing the previous owner of the given token ID
* @param tokenId uint256 ID of the token to be removed from the tokens list of the given address
*/
function _removeTokenFromOwnerEnumeration(address from, uint256 tokenId) private {
// To prevent a gap in from's tokens array, we store the last token in the index of the token to delete, and
// then delete the last slot (swap and pop).
uint256 lastTokenIndex = ERC721.balanceOf(from) - 1;
uint256 tokenIndex = _ownedTokensIndex[tokenId];
// When the token to delete is the last token, the swap operation is unnecessary
if (tokenIndex != lastTokenIndex) {
uint256 lastTokenId = _ownedTokens[from][lastTokenIndex];
_ownedTokens[from][tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
_ownedTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index
}
// This also deletes the contents at the last position of the array
delete _ownedTokensIndex[tokenId];
delete _ownedTokens[from][lastTokenIndex];
}
/**
* @dev Private function to remove a token from this extension's token tracking data structures.
* This has O(1) time complexity, but alters the order of the _allTokens array.
* @param tokenId uint256 ID of the token to be removed from the tokens list
*/
function _removeTokenFromAllTokensEnumeration(uint256 tokenId) private {
// To prevent a gap in the tokens array, we store the last token in the index of the token to delete, and
// then delete the last slot (swap and pop).
uint256 lastTokenIndex = _allTokens.length - 1;
uint256 tokenIndex = _allTokensIndex[tokenId];
// When the token to delete is the last token, the swap operation is unnecessary. However, since this occurs so
// rarely (when the last minted token is burnt) that we still do the swap here to avoid the gas cost of adding
// an 'if' statement (like in _removeTokenFromOwnerEnumeration)
uint256 lastTokenId = _allTokens[lastTokenIndex];
_allTokens[tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
_allTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index
// This also deletes the contents at the last position of the array
delete _allTokensIndex[tokenId];
_allTokens.pop();
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
* @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;
/**
* @dev Contract module that helps prevent reentrant calls to a function.
*
* Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
* available, which can be applied to functions to make sure there are no nested
* (reentrant) calls to them.
*
* Note that because there is a single `nonReentrant` guard, functions marked as
* `nonReentrant` may not call one another. This can be worked around by making
* those functions `private`, and then adding `external` `nonReentrant` entry
* points to them.
*
* TIP: If you would like to learn more about reentrancy and alternative ways
* to protect against it, check out our blog post
* https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
*/
abstract contract ReentrancyGuard {
// Booleans are more expensive than uint256 or any type that takes up a full
// word because each write operation emits an extra SLOAD to first read the
// slot's contents, replace the bits taken up by the boolean, and then write
// back. This is the compiler's defense against contract upgrades and
// pointer aliasing, and it cannot be disabled.
// The values being non-zero value makes deployment a bit more expensive,
// but in exchange the refund on every call to nonReentrant will be lower in
// amount. Since refunds are capped to a percentage of the total
// transaction's gas, it is best to keep them low in cases like this one, to
// increase the likelihood of the full refund coming into effect.
uint256 private constant _NOT_ENTERED = 1;
uint256 private constant _ENTERED = 2;
uint256 private _status;
constructor() {
_status = _NOT_ENTERED;
}
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* Calling a `nonReentrant` function from another `nonReentrant`
* function is not supported. It is possible to prevent this from happening
* by making the `nonReentrant` function external, and make it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
// On the first call to nonReentrant, _notEntered will be true
require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
// Any calls to nonReentrant after this point will fail
_status = _ENTERED;
_;
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = _NOT_ENTERED;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
* @dev Contract module which allows children to implement an emergency stop
* mechanism that can be triggered by an authorized account.
*
* This module is used through inheritance. It will make available the
* modifiers `whenNotPaused` and `whenPaused`, which can be applied to
* the functions of your contract. Note that they will not be pausable by
* simply including this module, only once the modifiers are put in place.
*/
abstract contract Pausable is Context {
/**
* @dev Emitted when the pause is triggered by `account`.
*/
event Paused(address account);
/**
* @dev Emitted when the pause is lifted by `account`.
*/
event Unpaused(address account);
bool private _paused;
/**
* @dev Initializes the contract in unpaused state.
*/
constructor() {
_paused = false;
}
/**
* @dev Returns true if the contract is paused, and false otherwise.
*/
function paused() public view virtual returns (bool) {
return _paused;
}
/**
* @dev Modifier to make a function callable only when the contract is not paused.
*
* Requirements:
*
* - The contract must not be paused.
*/
modifier whenNotPaused() {
require(!paused(), "Pausable: paused");
_;
}
/**
* @dev Modifier to make a function callable only when the contract is paused.
*
* Requirements:
*
* - The contract must be paused.
*/
modifier whenPaused() {
require(paused(), "Pausable: not paused");
_;
}
/**
* @dev Triggers stopped state.
*
* Requirements:
*
* - The contract must not be paused.
*/
function _pause() internal virtual whenNotPaused {
_paused = true;
emit Paused(_msgSender());
}
/**
* @dev Returns to normal state.
*
* Requirements:
*
* - The contract must be paused.
*/
function _unpause() internal virtual whenPaused {
_paused = false;
emit Unpaused(_msgSender());
}
}
// 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);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface LinkTokenInterface {
function allowance(
address owner,
address spender
)
external
view
returns (
uint256 remaining
);
function approve(
address spender,
uint256 value
)
external
returns (
bool success
);
function balanceOf(
address owner
)
external
view
returns (
uint256 balance
);
function decimals()
external
view
returns (
uint8 decimalPlaces
);
function decreaseApproval(
address spender,
uint256 addedValue
)
external
returns (
bool success
);
function increaseApproval(
address spender,
uint256 subtractedValue
) external;
function name()
external
view
returns (
string memory tokenName
);
function symbol()
external
view
returns (
string memory tokenSymbol
);
function totalSupply()
external
view
returns (
uint256 totalTokensIssued
);
function transfer(
address to,
uint256 value
)
external
returns (
bool success
);
function transferAndCall(
address to,
uint256 value,
bytes calldata data
)
external
returns (
bool success
);
function transferFrom(
address from,
address to,
uint256 value
)
external
returns (
bool success
);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
contract VRFRequestIDBase {
/**
* @notice returns the seed which is actually input to the VRF coordinator
*
* @dev To prevent repetition of VRF output due to repetition of the
* @dev user-supplied seed, that seed is combined in a hash with the
* @dev user-specific nonce, and the address of the consuming contract. The
* @dev risk of repetition is mostly mitigated by inclusion of a blockhash in
* @dev the final seed, but the nonce does protect against repetition in
* @dev requests which are included in a single block.
*
* @param _userSeed VRF seed input provided by user
* @param _requester Address of the requesting contract
* @param _nonce User-specific nonce at the time of the request
*/
function makeVRFInputSeed(
bytes32 _keyHash,
uint256 _userSeed,
address _requester,
uint256 _nonce
)
internal
pure
returns (
uint256
)
{
return uint256(keccak256(abi.encode(_keyHash, _userSeed, _requester, _nonce)));
}
/**
* @notice Returns the id for this request
* @param _keyHash The serviceAgreement ID to be used for this request
* @param _vRFInputSeed The seed to be passed directly to the VRF
* @return The id for this request
*
* @dev Note that _vRFInputSeed is not the seed passed by the consuming
* @dev contract, but the one generated by makeVRFInputSeed
*/
function makeRequestId(
bytes32 _keyHash,
uint256 _vRFInputSeed
)
internal
pure
returns (
bytes32
)
{
return keccak256(abi.encodePacked(_keyHash, _vRFInputSeed));
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./interfaces/LinkTokenInterface.sol";
import "./VRFRequestIDBase.sol";
/** ****************************************************************************
* @notice Interface for contracts using VRF randomness
* *****************************************************************************
* @dev PURPOSE
*
* @dev Reggie the Random Oracle (not his real job) wants to provide randomness
* @dev to Vera the verifier in such a way that Vera can be sure he's not
* @dev making his output up to suit himself. Reggie provides Vera a public key
* @dev to which he knows the secret key. Each time Vera provides a seed to
* @dev Reggie, he gives back a value which is computed completely
* @dev deterministically from the seed and the secret key.
*
* @dev Reggie provides a proof by which Vera can verify that the output was
* @dev correctly computed once Reggie tells it to her, but without that proof,
* @dev the output is indistinguishable to her from a uniform random sample
* @dev from the output space.
*
* @dev The purpose of this contract is to make it easy for unrelated contracts
* @dev to talk to Vera the verifier about the work Reggie is doing, to provide
* @dev simple access to a verifiable source of randomness.
* *****************************************************************************
* @dev USAGE
*
* @dev Calling contracts must inherit from VRFConsumerBase, and can
* @dev initialize VRFConsumerBase's attributes in their constructor as
* @dev shown:
*
* @dev contract VRFConsumer {
* @dev constuctor(<other arguments>, address _vrfCoordinator, address _link)
* @dev VRFConsumerBase(_vrfCoordinator, _link) public {
* @dev <initialization with other arguments goes here>
* @dev }
* @dev }
*
* @dev The oracle will have given you an ID for the VRF keypair they have
* @dev committed to (let's call it keyHash), and have told you the minimum LINK
* @dev price for VRF service. Make sure your contract has sufficient LINK, and
* @dev call requestRandomness(keyHash, fee, seed), where seed is the input you
* @dev want to generate randomness from.
*
* @dev Once the VRFCoordinator has received and validated the oracle's response
* @dev to your request, it will call your contract's fulfillRandomness method.
*
* @dev The randomness argument to fulfillRandomness is the actual random value
* @dev generated from your seed.
*
* @dev The requestId argument is generated from the keyHash and the seed by
* @dev makeRequestId(keyHash, seed). If your contract could have concurrent
* @dev requests open, you can use the requestId to track which seed is
* @dev associated with which randomness. See VRFRequestIDBase.sol for more
* @dev details. (See "SECURITY CONSIDERATIONS" for principles to keep in mind,
* @dev if your contract could have multiple requests in flight simultaneously.)
*
* @dev Colliding `requestId`s are cryptographically impossible as long as seeds
* @dev differ. (Which is critical to making unpredictable randomness! See the
* @dev next section.)
*
* *****************************************************************************
* @dev SECURITY CONSIDERATIONS
*
* @dev A method with the ability to call your fulfillRandomness method directly
* @dev could spoof a VRF response with any random value, so it's critical that
* @dev it cannot be directly called by anything other than this base contract
* @dev (specifically, by the VRFConsumerBase.rawFulfillRandomness method).
*
* @dev For your users to trust that your contract's random behavior is free
* @dev from malicious interference, it's best if you can write it so that all
* @dev behaviors implied by a VRF response are executed *during* your
* @dev fulfillRandomness method. If your contract must store the response (or
* @dev anything derived from it) and use it later, you must ensure that any
* @dev user-significant behavior which depends on that stored value cannot be
* @dev manipulated by a subsequent VRF request.
*
* @dev Similarly, both miners and the VRF oracle itself have some influence
* @dev over the order in which VRF responses appear on the blockchain, so if
* @dev your contract could have multiple VRF requests in flight simultaneously,
* @dev you must ensure that the order in which the VRF responses arrive cannot
* @dev be used to manipulate your contract's user-significant behavior.
*
* @dev Since the ultimate input to the VRF is mixed with the block hash of the
* @dev block in which the request is made, user-provided seeds have no impact
* @dev on its economic security properties. They are only included for API
* @dev compatability with previous versions of this contract.
*
* @dev Since the block hash of the block which contains the requestRandomness
* @dev call is mixed into the input to the VRF *last*, a sufficiently powerful
* @dev miner could, in principle, fork the blockchain to evict the block
* @dev containing the request, forcing the request to be included in a
* @dev different block with a different hash, and therefore a different input
* @dev to the VRF. However, such an attack would incur a substantial economic
* @dev cost. This cost scales with the number of blocks the VRF oracle waits
* @dev until it calls responds to a request.
*/
abstract contract VRFConsumerBase is VRFRequestIDBase {
/**
* @notice fulfillRandomness handles the VRF response. Your contract must
* @notice implement it. See "SECURITY CONSIDERATIONS" above for important
* @notice principles to keep in mind when implementing your fulfillRandomness
* @notice method.
*
* @dev VRFConsumerBase expects its subcontracts to have a method with this
* @dev signature, and will call it once it has verified the proof
* @dev associated with the randomness. (It is triggered via a call to
* @dev rawFulfillRandomness, below.)
*
* @param requestId The Id initially returned by requestRandomness
* @param randomness the VRF output
*/
function fulfillRandomness(
bytes32 requestId,
uint256 randomness
)
internal
virtual;
/**
* @dev In order to keep backwards compatibility we have kept the user
* seed field around. We remove the use of it because given that the blockhash
* enters later, it overrides whatever randomness the used seed provides.
* Given that it adds no security, and can easily lead to misunderstandings,
* we have removed it from usage and can now provide a simpler API.
*/
uint256 constant private USER_SEED_PLACEHOLDER = 0;
/**
* @notice requestRandomness initiates a request for VRF output given _seed
*
* @dev The fulfillRandomness method receives the output, once it's provided
* @dev by the Oracle, and verified by the vrfCoordinator.
*
* @dev The _keyHash must already be registered with the VRFCoordinator, and
* @dev the _fee must exceed the fee specified during registration of the
* @dev _keyHash.
*
* @dev The _seed parameter is vestigial, and is kept only for API
* @dev compatibility with older versions. It can't *hurt* to mix in some of
* @dev your own randomness, here, but it's not necessary because the VRF
* @dev oracle will mix the hash of the block containing your request into the
* @dev VRF seed it ultimately uses.
*
* @param _keyHash ID of public key against which randomness is generated
* @param _fee The amount of LINK to send with the request
*
* @return requestId unique ID for this request
*
* @dev The returned requestId can be used to distinguish responses to
* @dev concurrent requests. It is passed as the first argument to
* @dev fulfillRandomness.
*/
function requestRandomness(
bytes32 _keyHash,
uint256 _fee
)
internal
returns (
bytes32 requestId
)
{
LINK.transferAndCall(vrfCoordinator, _fee, abi.encode(_keyHash, USER_SEED_PLACEHOLDER));
// This is the seed passed to VRFCoordinator. The oracle will mix this with
// the hash of the block containing this request to obtain the seed/input
// which is finally passed to the VRF cryptographic machinery.
uint256 vRFSeed = makeVRFInputSeed(_keyHash, USER_SEED_PLACEHOLDER, address(this), nonces[_keyHash]);
// nonces[_keyHash] must stay in sync with
// VRFCoordinator.nonces[_keyHash][this], which was incremented by the above
// successful LINK.transferAndCall (in VRFCoordinator.randomnessRequest).
// This provides protection against the user repeating their input seed,
// which would result in a predictable/duplicate output, if multiple such
// requests appeared in the same block.
nonces[_keyHash] = nonces[_keyHash] + 1;
return makeRequestId(_keyHash, vRFSeed);
}
LinkTokenInterface immutable internal LINK;
address immutable private vrfCoordinator;
// Nonces for each VRF key from which randomness has been requested.
//
// Must stay in sync with VRFCoordinator[_keyHash][this]
mapping(bytes32 /* keyHash */ => uint256 /* nonce */) private nonces;
/**
* @param _vrfCoordinator address of VRFCoordinator contract
* @param _link address of LINK token contract
*
* @dev https://docs.chain.link/docs/link-token-contracts
*/
constructor(
address _vrfCoordinator,
address _link
) {
vrfCoordinator = _vrfCoordinator;
LINK = LinkTokenInterface(_link);
}
// rawFulfillRandomness is called by VRFCoordinator when it receives a valid VRF
// proof. rawFulfillRandomness then calls fulfillRandomness, after validating
// the origin of the call
function rawFulfillRandomness(
bytes32 requestId,
uint256 randomness
)
external
{
require(msg.sender == vrfCoordinator, "Only VRFCoordinator can fulfill");
fulfillRandomness(requestId, randomness);
}
}