Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "./ZooKeeper.sol";
// BambooField allows you to grow your Bamboo! Buy some seeds, and then harvest them for more Bamboo!
//
contract BambooField is ERC20("Seed", "SEED"), Ownable {
using SafeERC20 for IERC20;
using SafeMath for uint256;
// Info of each user that can buy seeds.
mapping (address => FarmUserInfo) public userInfo;
BambooToken public bamboo;
ZooKeeper public zooKeeper;
// Amount needed to register
uint256 public registerAmount;
// Amount locked as collateral
uint256 public depositPool;
// Minimum time to harvest. Also min time of lock in the deposit.
uint256 public minStakeTime;
struct FarmUserInfo {
uint256 amount; // Deposited Amount
uint poolId; // Pool ID of active staking LP
uint256 startTime; // Timestamp of registration
bool active; // Flag for checking if this entry is active.
uint256 endTime; // Last timestamp the user can buy seeds. Only used if this is not active
}
event RegisterAmountChanged(uint256 amount);
event StakeTimeChanged(uint256 time);
constructor(BambooToken _bamboo, ZooKeeper _zoo, uint256 _registerprice, uint256 _minstaketime) {
bamboo= _bamboo;
zooKeeper = _zoo;
registerAmount = _registerprice;
minStakeTime = _minstaketime;
}
// Register a staking pool to the user with a collateral payment
function register(uint _pid, uint256 _amount) public {
require( _pid < zooKeeper.getPoolLength() , "register: invalid pool");
require(_amount > registerAmount, "register: amount should be bigger than registerAmount");
require(userInfo[msg.sender].amount == 0, "register: already registered");
// Get the poolId
uint256 amount = zooKeeper.getLpAmount(_pid, msg.sender);
require(amount > 0, 'register: no LP on pool');
uint256 seedAmount = _amount.sub(registerAmount);
// move the registerAmount
IERC20(bamboo).safeTransferFrom(address(msg.sender), address(this), registerAmount);
depositPool = depositPool.add(registerAmount);
// save user data
userInfo[msg.sender] = FarmUserInfo(registerAmount, _pid, block.timestamp, true, 0);
// buy seeds with the rest
buy(seedAmount);
}
// Buy some Seeds with BAMBOO.
// Requires an active register of LP staking, or endTime still valid.
function buy(uint256 _amount) public {
// Checks if user is valid
if(!userInfo[msg.sender].active) {
require(userInfo[msg.sender].endTime >= block.timestamp, "buy: invalid user");
}
// Gets the amount of usable BAMBOO locked in the contract
uint256 totalBamboo = bamboo.balanceOf(address(this)).sub(depositPool);
// Gets the amount of Seeds in existence
uint256 totalShares = totalSupply();
// If no Seeds exists, mint it 1:1 to the amount put in
if (totalShares == 0 || totalBamboo == 0) {
_mint(msg.sender, _amount);
}
// Calculate and mint the amount of Seeds the BAMBOO is worth. The ratio will change overtime, as Seeds are burned/minted and BAMBOO is deposited + gained from fees / withdrawn.
else {
uint256 what = _amount.mul(totalShares).div(totalBamboo);
_mint(msg.sender, what);
}
// Lock the BAMBOO in the contract
IERC20(bamboo).safeTransferFrom(address(msg.sender), address(this), _amount);
}
// Harvest your BAMBOO
// Unlocks the staked + gained BAMBOO and burns Seeds
function harvest(uint256 _share) public {
// Checks if time is valid
require(block.timestamp.sub(userInfo[msg.sender].startTime) >= minStakeTime, "buy: cannot harvest seeds at this time");
// Gets the amount of Seeds in existence
uint256 totalShares = totalSupply();
uint256 totalBamboo = bamboo.balanceOf(address(this)).sub(depositPool);
// Calculates the amount of BAMBOO the Seeds are worth
uint256 what = _share.mul(totalBamboo).div(totalShares);
_burn(msg.sender, _share);
IERC20(bamboo).safeTransfer(msg.sender, what);
}
// Register a staking pool to the user with a collateral payment
function withdraw() public {
// Checks if timestamp is valid
require(block.timestamp.sub(userInfo[msg.sender].startTime) >= minStakeTime, "withdraw: cannot withdraw yet!");
// Harvest remaining seeds
uint256 seeds = balanceOf(msg.sender);
if (seeds>0){
harvest (seeds);
}
uint256 deposit = userInfo[msg.sender].amount;
// Reset user data
delete(userInfo[msg.sender]);
// Return deposit
IERC20(bamboo).safeTransfer(msg.sender, deposit);
depositPool = depositPool.sub(deposit);
}
// This function will be called from ZooKeeper if LP balance is withdrawn
function updatePool(address _user) external {
require(ZooKeeper(msg.sender) == zooKeeper, "updatePool: contract was not ZooKeeper");
userInfo[_user].active = false;
// Get 60 days to buy shares if you staked LP at least 60 days
if(block.timestamp - userInfo[_user].startTime >= 60 days){
userInfo[_user].endTime = block.timestamp + 60 days;
}
}
// Changes the entry collateral amount.
function setRegisterAmount(uint256 _amount) external onlyOwner {
registerAmount = _amount;
emit RegisterAmountChanged(registerAmount);
}
// Changes the min stake time in seconds.
function setStakeTime(uint256 _mintime) external onlyOwner {
minStakeTime = _mintime;
emit StakeTimeChanged(minStakeTime);
}
// Check if user is active with an specific pool
function isActive(address _user, uint _pid) public view returns(bool) {
return userInfo[_user].active && userInfo[_user].poolId == _pid;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "@openzeppelin/contracts/utils/EnumerableSet.sol";
import "./token/BambooToken.sol";
import "./BambooField.sol";
interface IMigratorKeeper {
// Perform LP token migration from legacy UniswapV2 to BambooDeFi.
// Take the current LP token address and return the new LP token address.
// Migrator should have full access to the caller's LP token.
// Return the new LP token address.
//
// XXX Migrator must have allowance access to UniswapV2 LP tokens.
// BambooDeFi must mint EXACTLY the same amount of BambooDeFi LP tokens or
// else something bad will happen. Traditional UniswapV2 does not
// do that so be careful!
function migrate(IERC20 token) external returns (IERC20);
}
// ZooKeeper is the master of pandas. He can make Bamboo and he is a fair guy.
//
// Note that it's ownable and the owner wields tremendous power. The ownership
// will be transferred to a governance smart contract once BAMBOO is sufficiently
// distributed and the community can show to govern itself.
//
contract ZooKeeper is Ownable {
using SafeMath for uint256;
using SafeERC20 for IERC20;
// Total time rewards
uint256 public constant TIME_REWARDS_LENGTH = 12;
// Lock times available in seconds for 1 day, 7 days, 15 days, 30 days, 60 days, 90 days, 180 days, 1 year, 2 years, 3 years, 4 years, 5 years
uint256[TIME_REWARDS_LENGTH] public timeRewards = [1 days, 7 days, 15 days, 30 days, 60 days, 90 days, 180 days, 365 days, 730 days, 1095 days, 1460 days, 1825 days];
// Lock times saved in a map, for quick validation
mapping(uint256 => bool) public validTimeRewards;
// Info of each user.
struct LpUserInfo {
uint256 amount; // How many LP tokens the user has provided.
uint256 rewardDebt; // Reward debt. See explanation below.
uint256 lastLpDeposit; // Last time user made a deposit
//
// We do some fancy math here. Basically, any point in time, the amount of BAMBOOs
// entitled to a user but is pending to be distributed is:
//
// pending reward = (user.amount * pool.accBambooPerShare) - user.rewardDebt
//
// Whenever a user deposits or withdraws LP tokens to a pool. Here's what happens:
// 1. The pool's `accBambooPerShare` (and `lastRewardBlock`) gets updated.
// 2. User receives the pending reward sent to his/her address.
// 3. User's `amount` gets updated.
// 4. User's `rewardDebt` gets updated.
}
struct BambooDeposit {
uint256 amount; // How many BAMBOO tokens the user has deposited.
uint256 lockTime; // Time in seconds that need to pass before this deposit can be withdrawn.
bool active; // Flag for checking if this entry is actively staking.
uint256 totalReward; // The total reward that will be collected from this deposit.
uint256 dailyReward; // The amount of bamboo that could be claimed daily.
uint256 lastTime; // Last timestamp when the daily rewards where collected.
}
struct BambooUserInfo {
mapping(uint256 => BambooDeposit) deposits; // Deposits from the user.
uint256[] ids; // Active deposits from the user.
uint256 totalAmount; // Total amount of active deposits from the user.
uint256 lastDeposit; // Timestamp of last deposit from user
}
struct StakeMultiplierInfo {
uint256[TIME_REWARDS_LENGTH] multiplierBonus; // Array of the different multipliers.
bool registered; // If this amount has been registered
}
struct YieldMultiplierInfo {
uint256 multiplier; // Multiplier value.
bool registered; // If this amount has been registered
}
// Info of each pool.
struct PoolInfo {
IERC20 lpToken; // Address of LP token contract.
uint256 allocPoint; // How many allocation points assigned to this pool. BAMBOOs to distribute per block.
uint256 lastRewardBlock; // Last block number that BAMBOOs distribution occurs.
uint256 accBambooPerShare; // Accumulated BAMBOOs per share, times 1e12. See below.
}
// The BAMBOO TOKEN
BambooToken public bamboo;
// BAMBOO tokens created per block.
uint256 public bambooPerBlock;
// The migrator contract. It has a lot of power. Can only be set through governance (owner).
IMigratorKeeper public migrator;
// The BambooField contract. If active, validates the lp staking for additional rewards.
BambooField public bambooField;
// If the BambooField is activated. Can be turned off by owner
bool public isField;
// Info of each pool.
PoolInfo[] public poolInfo;
// Info of each user that stakes LP tokens.
mapping(uint256 => mapping (address => LpUserInfo)) public userInfo;
// Info of the additional multipliers for BAMBOO staking
mapping(uint256 => StakeMultiplierInfo) public stakeMultipliers;
// Info of the multipliers available for YieldFarming + staking
mapping(uint256 => YieldMultiplierInfo) public yieldMultipliers;
// Amounts registered for yield multipliers
uint256[] public yieldAmounts;
// Info of each user that stakes BAMBOO.
mapping(address => BambooUserInfo) public bambooUserInfo;
// Total allocation points. Must be the sum of all allocation points in all pools.
uint256 public totalAllocPoint = 0;
// The block number when BAMBOO mining starts.
uint256 public startBlock;
// Min time of stake and yield for multiplier rewards
uint256 public minYieldTime = 7 days;
uint256 public minStakeTime = 1 days;
event Deposit(address indexed user, uint256 indexed pid, uint256 amount);
event BAMBOODeposit(address indexed user, uint256 amount, uint256 lockTime, uint256 id);
event Withdraw(address indexed user, uint256 indexed pid, uint256 amount);
event BAMBOOWithdraw(address indexed user, uint256 indexed pid, uint256 amount);
event BAMBOOBonusWithdraw(address indexed user, uint256 indexed pid, uint256 amount, uint256 ndays);
event EmergencyWithdraw(address indexed user, uint256 indexed pid, uint256 amount);
modifier onlyEOA() {
require(msg.sender == tx.origin, "ZooKeeper: must use EOA");
_;
}
constructor(BambooToken _bamboo, uint256 _bambooPerBlock, uint256 _startBlock) {
require(_bambooPerBlock > 0, "invalid bamboo per block");
bamboo = _bamboo;
bambooPerBlock = _bambooPerBlock;
startBlock = _startBlock;
for(uint i=0; i<TIME_REWARDS_LENGTH; i++) {
validTimeRewards[timeRewards[i]] = true;
}
}
// Add a new lp to the pool. Can only be called by the owner.
function add(uint256 _allocPoint, IERC20 _lpToken) public onlyOwner {
massUpdatePools();
checkPoolDuplicate(_lpToken);
uint256 lastRewardBlock = block.number > startBlock ? block.number : startBlock;
totalAllocPoint = totalAllocPoint.add(_allocPoint);
poolInfo.push(PoolInfo({
lpToken: _lpToken,
allocPoint: _allocPoint,
lastRewardBlock: lastRewardBlock,
accBambooPerShare: 0
}));
}
// Update the given pool's BAMBOO allocation point. Can only be called by the owner.
function set(uint256 _pid, uint256 _allocPoint) public onlyOwner {
massUpdatePools();
totalAllocPoint = totalAllocPoint.sub(poolInfo[_pid].allocPoint).add(_allocPoint);
poolInfo[_pid].allocPoint = _allocPoint;
}
// Set the migrator contract. Can only be called by the owner.
function setMigrator(IMigratorKeeper _migrator) public onlyOwner {
migrator = _migrator;
}
// Migrate lp token to another lp contract. We trust that migrator contract is correct.
function migrate(uint256 _pid) public onlyOwner {
require(address(migrator) != address(0), "migrate: no migrator");
PoolInfo storage pool = poolInfo[_pid];
IERC20 lpToken = pool.lpToken;
uint256 bal = lpToken.balanceOf(address(this));
lpToken.safeApprove(address(migrator), bal);
IERC20 newLpToken = migrator.migrate(lpToken);
require(bal == newLpToken.balanceOf(address(this)), "migrate: bad");
pool.lpToken = newLpToken;
}
// BambooDeFi setup
// Add a new row of bamboo staking rewards. E.G. 500 (bamboos) -> [10001 (x1.0001*10000), ... ].
// Adding an existing amount will repace it. Can only be called by the owner.
function addStakeMultiplier(uint256 _amount, uint256[TIME_REWARDS_LENGTH] memory _multiplierBonuses) public onlyOwner {
require(_amount > 0, "addStakeMultiplier: invalid amount");
// Validate that multipliers are valid
for(uint i=0; i<TIME_REWARDS_LENGTH; i++){
require(_multiplierBonuses[i] >= 10000, "addStakeMultiplier: invalid multiplier array");
}
uint mLength = _multiplierBonuses.length;
require(mLength== TIME_REWARDS_LENGTH, "addStakeMultiplier: invalid array length");
StakeMultiplierInfo memory mInfo = StakeMultiplierInfo({multiplierBonus: _multiplierBonuses, registered:true});
stakeMultipliers[_amount] = mInfo;
}
// Add a new amount for yield farming rewards. E.G. 500 (bamboos) -> 10001 (x1.0001*10000). Adding an existing amount will replace it.
// Can only be called by the owner.
function addYieldMultiplier(uint256 _amount, uint256 _multiplierBonus ) public onlyOwner {
require(_amount > 0, "addYieldMultiplier: invalid amount");
// 10000 is a x1 multiplier.
require(_multiplierBonus >= 10000, "addYieldMultiplier: invalid multiplier");
if(!yieldMultipliers[_amount].registered){
yieldAmounts.push(_amount);
}
YieldMultiplierInfo memory mInfo = YieldMultiplierInfo({multiplier: _multiplierBonus, registered:true});
yieldMultipliers[_amount] = mInfo;
}
// Remove. Will not affect current deposits, since rewards are calculated at deposit time.
function removeStakeMultiplier(uint256 _amount) public onlyOwner {
require(stakeMultipliers[_amount].registered, "removeStakeMultiplier: nothing to remove");
delete(stakeMultipliers[_amount]);
}
// Remove yieldMultiplier.
function removeYieldMultiplier(uint256 _amount) public onlyOwner {
require(yieldMultipliers[_amount].registered, "removeYieldMultiplier: nothing to remove");
// Find index
for(uint i=0; i<yieldAmounts.length; i++) {
if(yieldAmounts[i] == _amount){
// Remove
yieldAmounts[i] = yieldAmounts[yieldAmounts.length -1];
yieldAmounts.pop();
break;
}
}
delete(yieldMultipliers[_amount]);
}
// Return reward multiplier over the given the time spent staking and the amount locked
function getStakingMultiplier(uint256 _time, uint256 _amount) public view returns (uint256) {
uint256 index = getTimeEarned(_time);
StakeMultiplierInfo storage multiInfo = stakeMultipliers[_amount];
require(multiInfo.registered, "getStakingMultiplier: invalid amount");
uint256 res = multiInfo.multiplierBonus[index];
return res;
}
// Returns reward multiplier for yieldFarming + BambooStaking
function getYieldMultiplier(uint256 _amount) public view returns (uint256) {
uint256 key=0;
for(uint i=0; i<yieldAmounts.length; i++) {
if (_amount >= yieldAmounts[i] ) {
key = yieldAmounts[i];
}
}
if(key == 0) {
return 10000;
}
else {
return yieldMultipliers[key].multiplier;
}
}
// Returns the active deposits from a user.
function getDeposits(address _user) public view returns (uint256[] memory) {
return bambooUserInfo[_user].ids;
}
// Returns the deposit amount and the minimum timestamp where the deposit can be withdrawn.
function getDepositInfo(address _user, uint256 _id) public view returns (uint256, uint256) {
BambooDeposit storage _deposit = bambooUserInfo[_user].deposits[_id];
require(_deposit.active, "deposit does not exist");
return (_deposit.amount, _id.add(_deposit.lockTime));
}
// Returns amount of stake rewards available to claim, and the days that are being accounted.
function getClaimableBamboo(uint256 _id, address _addr ) public view returns(uint256, uint256) {
BambooUserInfo storage user = bambooUserInfo[_addr];
// If it's the last withdraw
if(block.timestamp >= _id.add(user.deposits[_id].lockTime) ){
uint pastdays = user.deposits[_id].lastTime.sub(_id).div(1 days);
uint256 leftToClaim = user.deposits[_id].totalReward.sub(pastdays.mul(user.deposits[_id].dailyReward));
return (leftToClaim, (user.deposits[_id].lockTime.div(1 days)).sub(pastdays));
}
else{
uint256 ndays = (block.timestamp.sub(user.deposits[_id].lastTime)).div(1 days);
return (ndays.mul(user.deposits[_id].dailyReward), ndays);
}
}
// View function to see pending BAMBOOs on frontend.
function pendingBamboo(uint256 _pid, address _user) external view returns (uint256) {
PoolInfo storage pool = poolInfo[_pid];
LpUserInfo storage user = userInfo[_pid][_user];
uint256 bambooUserAmount = bambooUserInfo[_user].totalAmount;
uint256 accBambooPerShare = pool.accBambooPerShare;
uint256 lpSupply = pool.lpToken.balanceOf(address(this));
uint256 yMultiplier = 10000;
if (block.timestamp - user.lastLpDeposit > minYieldTime && block.timestamp - bambooUserInfo[_user].lastDeposit > minStakeTime) {
yMultiplier = getYieldMultiplier(bambooUserAmount);
}
if (block.number > pool.lastRewardBlock && lpSupply != 0) {
uint256 multiplier = block.number.sub(pool.lastRewardBlock);
uint256 bambooReward = multiplier.mul(bambooPerBlock).mul(pool.allocPoint).div(totalAllocPoint);
accBambooPerShare = accBambooPerShare.add(bambooReward.mul(1e12).div(lpSupply));
}
uint256 pending = user.amount.mul(accBambooPerShare).div(1e12).sub(user.rewardDebt);
return yMultiplier.mul(pending).div(10000);
}
// View function to see pending BAMBOOS to claim on staking. Returns total amount of pending bamboo to claim in the future,
// and the amount available to claim at the moment.
function pendingStakeBamboo(uint256 _id, address _addr) external view returns (uint256, uint256) {
BambooUserInfo storage user = bambooUserInfo[_addr];
require(user.deposits[_id].active, "pendingStakeBamboo: invalid id");
uint256 claimable;
uint256 ndays;
(claimable, ndays) = getClaimableBamboo(_id, _addr);
if (block.timestamp.sub(user.deposits[_id].lastTime) >= user.deposits[_id].lockTime){
return (claimable, claimable);
}
else{
uint pastdays = user.deposits[_id].lastTime.sub(_id).div(1 days);
uint256 leftToClaim = user.deposits[_id].totalReward.sub(pastdays.mul(user.deposits[_id].dailyReward));
return (leftToClaim, claimable);
}
}
// Update reward variables for all pools. Be careful of gas spending!
function massUpdatePools() public {
uint256 length = poolInfo.length;
for (uint256 pid = 0; pid < length; ++pid) {
updatePool(pid);
}
}
// Update reward variables of the given pool to be up-to-date.
function updatePool(uint256 _pid) public {
PoolInfo storage pool = poolInfo[_pid];
if (block.number <= pool.lastRewardBlock) {
return;
}
uint256 lpSupply = pool.lpToken.balanceOf(address(this));
if (lpSupply == 0) {
pool.lastRewardBlock = block.number;
return;
}
uint256 multiplier = block.number.sub(pool.lastRewardBlock);
uint256 bambooReward = multiplier.mul(bambooPerBlock).mul(pool.allocPoint).div(totalAllocPoint);
bamboo.mint(address(this), bambooReward);
pool.accBambooPerShare = pool.accBambooPerShare.add(bambooReward.mul(1e12).div(lpSupply));
pool.lastRewardBlock = block.number;
}
// Deposit Functions
// Deposit LP tokens to ZooKeeper for BAMBOO allocation.
function deposit(uint256 _pid, uint256 _amount) public onlyEOA {
require ( _pid < poolInfo.length , "deposit: pool exists?");
PoolInfo storage pool = poolInfo[_pid];
LpUserInfo storage user = userInfo[_pid][msg.sender];
uint256 bambooUserAmount = bambooUserInfo[msg.sender].totalAmount;
updatePool(_pid);
if (user.amount > 0) {
// Allocate how much bamboo corresponds to user
uint256 pending = user.amount.mul(pool.accBambooPerShare).div(1e12).sub(user.rewardDebt);
// If user has pending rewards from previous blocks
if (pending > 0) {
uint256 bonus = mintBonusBamboo(pending, user.lastLpDeposit, bambooUserInfo[msg.sender].lastDeposit, bambooUserAmount);
safeBambooTransfer(msg.sender, pending.add(bonus));
}
}
// Now take care of the new deposit
if(_amount > 0) {
pool.lpToken.safeTransferFrom(address(msg.sender), address(this), _amount);
user.amount = user.amount.add(_amount);
user.lastLpDeposit = block.timestamp;
}
user.rewardDebt = user.amount.mul(pool.accBambooPerShare).div(1e12);
emit Deposit(msg.sender, _pid, _amount);
}
// Deposit Bamboo to ZooKeeper for additional staking rewards. Bamboos should be approved
function depositBamboo(uint256 _amount, uint256 _lockTime) public onlyEOA {
require(stakeMultipliers[_amount].registered, "depositBamboo: invalid amount");
require(validTimeRewards[_lockTime] , "depositBamboo: invalid lockTime");
BambooUserInfo storage user = bambooUserInfo[msg.sender];
require(!user.deposits[block.timestamp].active, "depositBamboo: only 1 deposit per block!");
if(_amount > 0) {
IERC20(bamboo).safeTransferFrom(address(msg.sender), address(this), _amount);
// Calculate the final rewards
uint256 multiplier = getStakingMultiplier(_lockTime, _amount);
uint256 pending = (multiplier.mul(_amount).div(10000)).sub(_amount);
uint totaldays = _lockTime / 1 days;
BambooDeposit memory depositData = BambooDeposit({
amount: _amount,
lockTime: _lockTime,
active: true,
totalReward:pending,
dailyReward:pending.div(totaldays),
lastTime: block.timestamp
});
user.ids.push(block.timestamp);
user.deposits[block.timestamp] = depositData;
user.totalAmount = user.totalAmount.add(_amount);
user.lastDeposit = block.timestamp;
}
emit BAMBOODeposit(msg.sender, _amount, _lockTime, block.timestamp);
}
// Withdraw Functions
// Withdraw LP tokens from ZooKeeper.
function withdraw(uint256 _pid, uint256 _amount) public onlyEOA {
PoolInfo storage pool = poolInfo[_pid];
LpUserInfo storage user = userInfo[_pid][msg.sender];
uint256 bambooUserAmount = bambooUserInfo[msg.sender].totalAmount;
require(user.amount >= _amount, "withdraw: not good");
updatePool(_pid);
uint256 pending = user.amount.mul(pool.accBambooPerShare).div(1e12).sub(user.rewardDebt);
if(pending > 0) {
uint256 bonus = mintBonusBamboo(pending, user.lastLpDeposit, bambooUserInfo[msg.sender].lastDeposit, bambooUserAmount);
safeBambooTransfer(msg.sender, pending.add(bonus));
}
if(_amount > 0){
user.amount = user.amount.sub(_amount);
pool.lpToken.safeTransfer(address(msg.sender), _amount);
// Notify the BambooField if active
if(user.amount == 0 && isField){
if(bambooField.isActive(msg.sender, _pid)){
bambooField.updatePool(msg.sender);
}
}
}
user.rewardDebt = user.amount.mul(pool.accBambooPerShare).div(1e12);
emit Withdraw(msg.sender, _pid, _amount);
}
// Withdraw a Bamboo deposit from ZooKeeper.
function withdrawBamboo(uint256 _depositId) public onlyEOA {
BambooUserInfo storage user = bambooUserInfo[msg.sender];
require(user.deposits[_depositId].active, "withdrawBamboo: invalid id");
uint256 depositEnd = _depositId.add(user.deposits[_depositId].lockTime) ;
// Get the depositIndex for deleting it later from the active ids
uint depositIndex = 0;
for (uint i=0; i<user.ids.length; i++){
if (user.ids[i] == _depositId){
depositIndex = i;
break;
}
}
require(user.ids[depositIndex] == _depositId, "withdrawBamboo: invalid id");
// User cannot withdraw before the lockTime
require(block.timestamp >= depositEnd, "withdrawBamboo: cannot withdraw yet!");
uint256 amount = user.deposits[_depositId].amount;
withdrawDailyBamboo(_depositId);
// Clean up the removed deposit
user.ids[depositIndex] = user.ids[user.ids.length -1];
user.ids.pop();
user.totalAmount = user.totalAmount.sub(user.deposits[_depositId].amount);
delete user.deposits[_depositId];
safeBambooTransfer(msg.sender, amount);
emit BAMBOOWithdraw(msg.sender, _depositId, amount);
}
// Withdraw the bonus staking Bamboo available from this deposit.
function withdrawDailyBamboo(uint256 _depositId) public onlyEOA {
BambooUserInfo storage user = bambooUserInfo[msg.sender];
require(user.deposits[_depositId].active, "withdrawDailyBamboo: invalid id");
uint256 depositEnd = _depositId.add(user.deposits[_depositId].lockTime);
uint256 amount;
uint256 ndays;
(amount, ndays) = getClaimableBamboo(_depositId, msg.sender);
uint256 newLastTime = user.deposits[_depositId].lastTime.add(ndays.mul(1 days));
assert(newLastTime <= depositEnd);
user.deposits[_depositId].lastTime = newLastTime;
// Mint the bonus bamboo
bamboo.mint(msg.sender, amount);
emit BAMBOOBonusWithdraw(msg.sender, _depositId, amount, ndays);
}
function mintBonusBamboo(uint256 pending, uint256 lastLp, uint256 lastStake, uint256 bambooUserAmount) internal returns (uint256) {
// Check if user is eligible for a multiplier, depending of last time of lp && bamboo deposit
if (block.timestamp - lastLp > minYieldTime && block.timestamp - lastStake > minStakeTime && bambooUserAmount > 0) {
uint256 multiplier = getYieldMultiplier(bambooUserAmount);
// Pending*multiplier
uint256 pmul = multiplier.mul(pending).div(10000);
// Bonus BAMBOO from multiplier
uint256 bonus = pmul.sub(pending);
// Mint the bonus
bamboo.mint(address(this), bonus);
return bonus;
}
return 0;
}
// Withdraw LPs without caring about rewards. EMERGENCY ONLY.
function emergencyWithdraw(uint256 _pid) public {
PoolInfo storage pool = poolInfo[_pid];
LpUserInfo storage user = userInfo[_pid][msg.sender];
uint256 _amount=user.amount;
user.amount = 0;
user.rewardDebt = 0;
pool.lpToken.safeTransfer(address(msg.sender), _amount);
emit EmergencyWithdraw(msg.sender, _pid, _amount);
}
// Return the index of the time reward that can be claimed.
function getTimeEarned(uint256 _time) internal view returns (uint256) {
require(_time >= timeRewards[0], "getTimeEarned: invalid time");
uint256 index=0;
for(uint i=1; i<TIME_REWARDS_LENGTH; i++) {
if (_time >= timeRewards[i] ) {
index = i;
}
else{
break;
}
}
return index;
}
// Safe bamboo transfer function, just in case if rounding error causes pool to not have enough BAMBOOs.
function safeBambooTransfer(address _to, uint256 _amount) internal {
uint256 bambooBal = bamboo.balanceOf(address(this));
if (_amount > bambooBal) {
IERC20(bamboo).safeTransfer(_to, bambooBal);
} else {
IERC20(bamboo).safeTransfer(_to, _amount);
}
}
function checkPoolDuplicate (IERC20 _lpToken) public view {
uint256 length = poolInfo.length;
for(uint256 pid = 0; pid < length ; ++pid) {
require (poolInfo[pid].lpToken != _lpToken , "add: existing pool?");
}
}
function getPoolLength() public view returns(uint count) {
return poolInfo.length;
}
function getLpAmount(uint _pid, address _user) public view returns(uint256) {
return userInfo[_pid][_user].amount;
}
// Switch BambooField active.
function switchBamboField(BambooField _bf) public onlyOwner {
if(isField){
isField = false;
}
else{
isField = true;
bambooField = _bf;
}
}
// Claim ownership for token
function claimToken() public onlyOwner {
// Bamboo Token should have proposedOwner before this
bamboo.claimOwnership();
}
// Update minYieldTime ans minStakeTime in seconds. If it's too big, would disable yield bonuses.
function minYield(uint256 _yTime, uint256 _sTime) public onlyOwner {
minYieldTime = _yTime;
minStakeTime = _sTime;
}
// Change bamboo per block. Affects rewards for all users.
function changeBambooPerBlock(uint256 _bamboo) public onlyOwner {
require(_bamboo > 0, "changeBambooPerBlock: invalid amount");
bambooPerBlock = _bamboo;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import "@openzeppelin/contracts/math/SafeMath.sol";
import "./Ownable.sol";
//BambooToken with Governance
contract BambooToken is ERC20("BambooDeFi", "BAMBOO"), Ownable {
using SafeMath for uint256;
/// @dev A record of each accounts delegate
mapping(address => address) internal _delegates;
/// @notice A checkpoint for marking number of votes from a given block
struct Checkpoint {
uint256 fromBlock;
uint256 votes;
}
/// @notice A record of votes checkpoints for each account, by index
mapping(address => mapping(uint32 => Checkpoint)) public checkpoints;
/// @notice The number of checkpoints for each account
mapping(address => uint32) public numCheckpoints;
/// @notice The EIP-712 typehash for the contract's domain
bytes32 public constant DOMAIN_TYPEHASH = keccak256(
"EIP712Domain(string name,uint256 chainId,address verifyingContract)"
);
/// @notice The EIP-712 typehash for the delegation struct used by the contract
bytes32 public constant DELEGATION_TYPEHASH = keccak256(
"Delegation(address delegatee,uint256 nonce,uint256 expiry)"
);
/// @notice A record of states for signing / validating signatures
mapping(address => uint256) public nonces;
/// @notice An event thats emitted when an account changes its delegate
event DelegateChanged(
address indexed delegator,
address indexed fromDelegate,
address indexed toDelegate
);
/// @notice An event thats emitted when a delegate account's vote balance changes
event DelegateVotesChanged(
address indexed delegate,
uint256 previousBalance,
uint256 newBalance
);
event Minted(
address indexed minter,
address indexed receiver,
uint256 mintAmount
);
event Burned(address indexed burner, uint256 burnAmount);
function mint(address _to, uint256 _amount) public onlyOwner {
_mint(_to, _amount);
emit Minted(owner(), _to, _amount);
}
function burn(uint256 _amount) public {
_burn(msg.sender, _amount);
emit Burned(msg.sender, _amount);
}
/**
* @notice Delegate votes from `msg.sender` to `delegatee`
* @param delegatee The address to delegate votes to
*/
function delegate(address delegatee) external {
return _delegate(msg.sender, delegatee);
}
/**
* @notice Delegates votes from signatory to `delegatee`
* @param delegatee The address to delegate votes to
* @param nonce The contract state required to match the signature
* @param expiry The time at which to expire the signature
* @param v The recovery byte of the signature
* @param r Half of the ECDSA signature pair
* @param s Half of the ECDSA signature pair
*/
function delegateBySig(
address delegatee,
uint256 nonce,
uint256 expiry,
uint8 v,
bytes32 r,
bytes32 s
) external {
bytes32 domainSeparator = keccak256(
abi.encode(
DOMAIN_TYPEHASH,
keccak256(bytes(name())),
getChainId(),
address(this)
)
);
bytes32 structHash = keccak256(
abi.encode(DELEGATION_TYPEHASH, delegatee, nonce, expiry)
);
bytes32 digest = keccak256(
abi.encodePacked("\x19\x01", domainSeparator, structHash)
);
address signatory = ecrecover(digest, v, r, s);
require(
signatory != address(0),
"BAMBOO::delegateBySig: invalid signature"
);
require(
nonce == nonces[signatory]++,
"BAMBOO::delegateBySig: invalid nonce"
);
require(block.timestamp <= expiry, "BAMBOO::delegateBySig: signature expired");
return _delegate(signatory, delegatee);
}
/**
* @notice Delegate votes from `msg.sender` to `delegatee`
* @param delegator The address to get delegatee for
*/
function delegates(address delegator) external view returns (address) {
return _delegates[delegator];
}
/**
* @notice Gets the current votes balance for `account`
* @param account The address to get votes balance
* @return The number of current votes for `account`
*/
function getCurrentVotes(address account) external view returns (uint256) {
uint32 nCheckpoints = numCheckpoints[account];
return
nCheckpoints > 0 ? checkpoints[account][nCheckpoints - 1].votes : 0;
}
/**
* @notice Determine the prior number of votes for an account as of a block number
* @dev Block number must be a finalized block or else this function will revert to prevent misinformation.
* @param account The address of the account to check
* @param blockNumber The block number to get the vote balance at
* @return The number of votes the account had as of the given block
*/
function getPriorVotes(address account, uint256 blockNumber)
external
view
returns (uint256)
{
require(
blockNumber < block.number,
"BAMBOO::getPriorVotes: not yet determined"
);
uint32 nCheckpoints = numCheckpoints[account];
if (nCheckpoints == 0) {
return 0;
}
// First check most recent balance
if (checkpoints[account][nCheckpoints - 1].fromBlock <= blockNumber) {
return checkpoints[account][nCheckpoints - 1].votes;
}
// Next check implicit zero balance
if (checkpoints[account][0].fromBlock > blockNumber) {
return 0;
}
uint32 lower = 0;
uint32 upper = nCheckpoints - 1;
while (upper > lower) {
uint32 center = upper - (upper - lower) / 2; // ceil, avoiding overflow
Checkpoint memory cp = checkpoints[account][center];
if (cp.fromBlock == blockNumber) {
return cp.votes;
} else if (cp.fromBlock < blockNumber) {
lower = center;
} else {
upper = center - 1;
}
}
return checkpoints[account][lower].votes;
}
function _delegate(address delegator, address delegatee) internal {
address currentDelegate = _delegates[delegator];
uint256 delegatorBalance = balanceOf(delegator); // balance of underlying BAMBOOs (not scaled);
_delegates[delegator] = delegatee;
emit DelegateChanged(delegator, currentDelegate, delegatee);
_moveDelegates(currentDelegate, delegatee, delegatorBalance);
}
function _moveDelegates(
address srcRep,
address dstRep,
uint256 amount
) internal {
if (srcRep != dstRep && amount > 0) {
if (srcRep != address(0)) {
// decrease old representative
uint32 srcRepNum = numCheckpoints[srcRep];
uint256 srcRepOld = srcRepNum > 0
? checkpoints[srcRep][srcRepNum - 1].votes
: 0;
uint256 srcRepNew = srcRepOld.sub(amount);
_writeCheckpoint(srcRep, srcRepNum, srcRepOld, srcRepNew);
}
if (dstRep != address(0)) {
// increase new representative
uint32 dstRepNum = numCheckpoints[dstRep];
uint256 dstRepOld = dstRepNum > 0
? checkpoints[dstRep][dstRepNum - 1].votes
: 0;
uint256 dstRepNew = dstRepOld.add(amount);
_writeCheckpoint(dstRep, dstRepNum, dstRepOld, dstRepNew);
}
}
}
function _writeCheckpoint(
address delegatee,
uint32 nCheckpoints,
uint256 oldVotes,
uint256 newVotes
) internal {
uint256 blockNumber = block.number;
if (
nCheckpoints > 0 &&
checkpoints[delegatee][nCheckpoints - 1].fromBlock == blockNumber
) {
checkpoints[delegatee][nCheckpoints - 1].votes = newVotes;
} else {
checkpoints[delegatee][nCheckpoints] = Checkpoint(
blockNumber,
newVotes
);
numCheckpoints[delegatee] = nCheckpoints + 1;
}
emit DelegateVotesChanged(delegatee, oldVotes, newVotes);
}
function getChainId() internal pure returns (uint256) {
uint256 chainId;
assembly {
chainId := chainid()
}
return chainId;
}
function _beforeTokenTransfer(
address from,
address to,
uint256 amount
) internal virtual override {
_moveDelegates(_delegates[from], _delegates[to], amount);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "@openzeppelin/contracts/GSN/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 {proposeOwner/claimOwnership}.
*
* 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.
*/
contract Ownable is Context {
address private _owner;
address private proposedOwner;
event OwnershipTransferred(
address indexed previousOwner,
address indexed newOwner
);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor() {
address msgSender = _msgSender();
_owner = msgSender;
emit OwnershipTransferred(address(0), msgSender);
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view 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 {
emit OwnershipTransferred(_owner, address(0));
_owner = address(0);
proposedOwner = address(0);
}
/**
* @dev Proposes a new owner of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function proposeOwner(address _proposedOwner) public onlyOwner {
require(msg.sender != _proposedOwner, "ERROR_CALLER_ALREADY_OWNER");
proposedOwner = _proposedOwner;
}
/**
* @dev If the address has been proposed, it can accept the ownership,
* Can only be called by the current proposed owner.
*/
function claimOwnership() public {
require(msg.sender == proposedOwner, "ERROR_NOT_PROPOSED_OWNER");
emit OwnershipTransferred(_owner, proposedOwner);
_owner = proposedOwner;
proposedOwner = address(0);
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <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 GSN 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 payable) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes memory) {
this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
return msg.data;
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
*
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return sub(a, b, "SafeMath: subtraction overflow");
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b <= a, errorMessage);
uint256 c = a - b;
return c;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
*
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return div(a, b, "SafeMath: division by zero");
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts with custom message on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b > 0, errorMessage);
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
return mod(a, b, "SafeMath: modulo by zero");
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts with custom message when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b != 0, errorMessage);
return a % b;
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "../../GSN/Context.sol";
import "./IERC20.sol";
import "../../math/SafeMath.sol";
/**
* @dev Implementation of the {IERC20} interface.
*
* This implementation is agnostic to the way tokens are created. This means
* that a supply mechanism has to be added in a derived contract using {_mint}.
* For a generic mechanism see {ERC20PresetMinterPauser}.
*
* TIP: For a detailed writeup see our guide
* https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
* to implement supply mechanisms].
*
* We have followed general OpenZeppelin guidelines: functions revert instead
* of returning `false` on failure. This behavior is nonetheless conventional
* and does not conflict with the expectations of ERC20 applications.
*
* Additionally, an {Approval} event is emitted on calls to {transferFrom}.
* This allows applications to reconstruct the allowance for all accounts just
* by listening to said events. Other implementations of the EIP may not emit
* these events, as it isn't required by the specification.
*
* Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
* functions have been added to mitigate the well-known issues around setting
* allowances. See {IERC20-approve}.
*/
contract ERC20 is Context, IERC20 {
using SafeMath for uint256;
mapping (address => uint256) private _balances;
mapping (address => mapping (address => uint256)) private _allowances;
uint256 private _totalSupply;
string private _name;
string private _symbol;
uint8 private _decimals;
/**
* @dev Sets the values for {name} and {symbol}, initializes {decimals} with
* a default value of 18.
*
* To select a different value for {decimals}, use {_setupDecimals}.
*
* All three of these values are immutable: they can only be set once during
* construction.
*/
constructor (string memory name_, string memory symbol_) public {
_name = name_;
_symbol = symbol_;
_decimals = 18;
}
/**
* @dev Returns the name of the token.
*/
function name() public view returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view returns (string memory) {
return _symbol;
}
/**
* @dev Returns the number of decimals used to get its user representation.
* For example, if `decimals` equals `2`, a balance of `505` tokens should
* be displayed to a user as `5,05` (`505 / 10 ** 2`).
*
* Tokens usually opt for a value of 18, imitating the relationship between
* Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
* called.
*
* NOTE: This information is only used for _display_ purposes: it in
* no way affects any of the arithmetic of the contract, including
* {IERC20-balanceOf} and {IERC20-transfer}.
*/
function decimals() public view returns (uint8) {
return _decimals;
}
/**
* @dev See {IERC20-totalSupply}.
*/
function totalSupply() public view override returns (uint256) {
return _totalSupply;
}
/**
* @dev See {IERC20-balanceOf}.
*/
function balanceOf(address account) public view override returns (uint256) {
return _balances[account];
}
/**
* @dev See {IERC20-transfer}.
*
* Requirements:
*
* - `recipient` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/
function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
_transfer(_msgSender(), recipient, amount);
return true;
}
/**
* @dev See {IERC20-allowance}.
*/
function allowance(address owner, address spender) public view virtual override returns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See {IERC20-approve}.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 amount) public virtual override returns (bool) {
_approve(_msgSender(), spender, amount);
return true;
}
/**
* @dev See {IERC20-transferFrom}.
*
* Emits an {Approval} event indicating the updated allowance. This is not
* required by the EIP. See the note at the beginning of {ERC20}.
*
* Requirements:
*
* - `sender` and `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `amount`.
* - the caller must have allowance for ``sender``'s tokens of at least
* `amount`.
*/
function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
_transfer(sender, recipient, amount);
_approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
return true;
}
/**
* @dev Atomically increases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
_approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
return true;
}
/**
* @dev Atomically decreases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `spender` must have allowance for the caller of at least
* `subtractedValue`.
*/
function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
_approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
return true;
}
/**
* @dev Moves tokens `amount` from `sender` to `recipient`.
*
* This is internal function is equivalent to {transfer}, and can be used to
* e.g. implement automatic token fees, slashing mechanisms, etc.
*
* Emits a {Transfer} event.
*
* Requirements:
*
* - `sender` cannot be the zero address.
* - `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `amount`.
*/
function _transfer(address sender, address recipient, uint256 amount) internal virtual {
require(sender != address(0), "ERC20: transfer from the zero address");
require(recipient != address(0), "ERC20: transfer to the zero address");
_beforeTokenTransfer(sender, recipient, amount);
_balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
_balances[recipient] = _balances[recipient].add(amount);
emit Transfer(sender, recipient, amount);
}
/** @dev Creates `amount` tokens and assigns them to `account`, increasing
* the total supply.
*
* Emits a {Transfer} event with `from` set to the zero address.
*
* Requirements:
*
* - `to` cannot be the zero address.
*/
function _mint(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: mint to the zero address");
_beforeTokenTransfer(address(0), account, amount);
_totalSupply = _totalSupply.add(amount);
_balances[account] = _balances[account].add(amount);
emit Transfer(address(0), account, amount);
}
/**
* @dev Destroys `amount` tokens from `account`, reducing the
* total supply.
*
* Emits a {Transfer} event with `to` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
* - `account` must have at least `amount` tokens.
*/
function _burn(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: burn from the zero address");
_beforeTokenTransfer(account, address(0), amount);
_balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
_totalSupply = _totalSupply.sub(amount);
emit Transfer(account, address(0), amount);
}
/**
* @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
*
* This internal function is equivalent to `approve`, and can be used to
* e.g. set automatic allowances for certain subsystems, etc.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `owner` cannot be the zero address.
* - `spender` cannot be the zero address.
*/
function _approve(address owner, address spender, uint256 amount) internal virtual {
require(owner != address(0), "ERC20: approve from the zero address");
require(spender != address(0), "ERC20: approve to the zero address");
_allowances[owner][spender] = amount;
emit Approval(owner, spender, amount);
}
/**
* @dev Sets {decimals} to a value other than the default one of 18.
*
* WARNING: This function should only be called from the constructor. Most
* applications that interact with token contracts will not expect
* {decimals} to ever change, and may work incorrectly if it does.
*/
function _setupDecimals(uint8 decimals_) internal {
_decimals = decimals_;
}
/**
* @dev Hook that is called before any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* will be to transferred to `to`.
* - when `from` is zero, `amount` tokens will be minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens 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 amount) internal virtual { }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <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 >=0.6.0 <0.8.0;
import "./IERC20.sol";
import "../../math/SafeMath.sol";
import "../../utils/Address.sol";
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20 {
using SafeMath for uint256;
using Address for address;
function safeTransfer(IERC20 token, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IERC20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
function safeApprove(IERC20 token, address spender, uint256 value) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
// solhint-disable-next-line max-line-length
require((value == 0) || (token.allowance(address(this), spender) == 0),
"SafeERC20: approve from non-zero to non-zero allowance"
);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender).add(value);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function _callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
// the target address contains contract code and also asserts for success in the low-level call.
bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
if (returndata.length > 0) { // Return data is optional
// solhint-disable-next-line max-line-length
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.2 <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;
// solhint-disable-next-line no-inline-assembly
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");
// solhint-disable-next-line avoid-low-level-calls, avoid-call-value
(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");
// solhint-disable-next-line avoid-low-level-calls
(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");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.staticcall(data);
return _verifyCallResult(success, returndata, errorMessage);
}
function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
// solhint-disable-next-line no-inline-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <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;
// When the value to delete is the last one, the swap operation is unnecessary. However, since this occurs
// so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.
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] = toDeleteIndex + 1; // All indexes are 1-based
// 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) {
require(set._values.length > index, "EnumerableSet: index out of bounds");
return set._values[index];
}
// 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);
}
// 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(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(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(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(uint256(_at(set._inner, index)));
}
// 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));
}
}