// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import {IERC20, SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import {TokenDistributor} from "./TokenDistributor.sol";
/**
 * @title FeeSharingSystem
 * @notice It handles the distribution of fees using
 * WETH along with the auto-compounding of LOOKS.
 */
contract FeeSharingSystem is ReentrancyGuard, Ownable {
    using SafeERC20 for IERC20;
    struct UserInfo {
        uint256 shares; // shares of token staked
        uint256 userRewardPerTokenPaid; // user reward per token paid
        uint256 rewards; // pending rewards
    }
    // Precision factor for calculating rewards and exchange rate
    uint256 public constant PRECISION_FACTOR = 10**18;
    IERC20 public immutable looksRareToken;
    IERC20 public immutable rewardToken;
    TokenDistributor public immutable tokenDistributor;
    // Reward rate (block)
    uint256 public currentRewardPerBlock;
    // Last reward adjustment block number
    uint256 public lastRewardAdjustment;
    // Last update block for rewards
    uint256 public lastUpdateBlock;
    // Current end block for the current reward period
    uint256 public periodEndBlock;
    // Reward per token stored
    uint256 public rewardPerTokenStored;
    // Total existing shares
    uint256 public totalShares;
    mapping(address => UserInfo) public userInfo;
    event Deposit(address indexed user, uint256 amount, uint256 harvestedAmount);
    event Harvest(address indexed user, uint256 harvestedAmount);
    event NewRewardPeriod(uint256 numberBlocks, uint256 rewardPerBlock, uint256 reward);
    event Withdraw(address indexed user, uint256 amount, uint256 harvestedAmount);
    /**
     * @notice Constructor
     * @param _looksRareToken address of the token staked (LOOKS)
     * @param _rewardToken address of the reward token
     * @param _tokenDistributor address of the token distributor contract
     */
    constructor(
        address _looksRareToken,
        address _rewardToken,
        address _tokenDistributor
    ) {
        rewardToken = IERC20(_rewardToken);
        looksRareToken = IERC20(_looksRareToken);
        tokenDistributor = TokenDistributor(_tokenDistributor);
    }
    /**
     * @notice Deposit staked tokens (and collect reward tokens if requested)
     * @param amount amount to deposit (in LOOKS)
     * @param claimRewardToken whether to claim reward tokens
     * @dev There is a limit of 1 LOOKS per deposit to prevent potential manipulation of current shares
     */
    function deposit(uint256 amount, bool claimRewardToken) external nonReentrant {
        require(amount >= PRECISION_FACTOR, "Deposit: Amount must be >= 1 LOOKS");
        // Auto compounds for everyone
        tokenDistributor.harvestAndCompound();
        // Update reward for user
        _updateReward(msg.sender);
        // Retrieve total amount staked by this contract
        (uint256 totalAmountStaked, ) = tokenDistributor.userInfo(address(this));
        // Transfer LOOKS tokens to this address
        looksRareToken.safeTransferFrom(msg.sender, address(this), amount);
        uint256 currentShares;
        // Calculate the number of shares to issue for the user
        if (totalShares != 0) {
            currentShares = (amount * totalShares) / totalAmountStaked;
            // This is a sanity check to prevent deposit for 0 shares
            require(currentShares != 0, "Deposit: Fail");
        } else {
            currentShares = amount;
        }
        // Adjust internal shares
        userInfo[msg.sender].shares += currentShares;
        totalShares += currentShares;
        uint256 pendingRewards;
        if (claimRewardToken) {
            // Fetch pending rewards
            pendingRewards = userInfo[msg.sender].rewards;
            if (pendingRewards > 0) {
                userInfo[msg.sender].rewards = 0;
                rewardToken.safeTransfer(msg.sender, pendingRewards);
            }
        }
        // Verify LOOKS token allowance and adjust if necessary
        _checkAndAdjustLOOKSTokenAllowanceIfRequired(amount, address(tokenDistributor));
        // Deposit user amount in the token distributor contract
        tokenDistributor.deposit(amount);
        emit Deposit(msg.sender, amount, pendingRewards);
    }
    /**
     * @notice Harvest reward tokens that are pending
     */
    function harvest() external nonReentrant {
        // Auto compounds for everyone
        tokenDistributor.harvestAndCompound();
        // Update reward for user
        _updateReward(msg.sender);
        // Retrieve pending rewards
        uint256 pendingRewards = userInfo[msg.sender].rewards;
        // If pending rewards are null, revert
        require(pendingRewards > 0, "Harvest: Pending rewards must be > 0");
        // Adjust user rewards and transfer
        userInfo[msg.sender].rewards = 0;
        // Transfer reward token to sender
        rewardToken.safeTransfer(msg.sender, pendingRewards);
        emit Harvest(msg.sender, pendingRewards);
    }
    /**
     * @notice Withdraw staked tokens (and collect reward tokens if requested)
     * @param shares shares to withdraw
     * @param claimRewardToken whether to claim reward tokens
     */
    function withdraw(uint256 shares, bool claimRewardToken) external nonReentrant {
        require(
            (shares > 0) && (shares <= userInfo[msg.sender].shares),
            "Withdraw: Shares equal to 0 or larger than user shares"
        );
        _withdraw(shares, claimRewardToken);
    }
    /**
     * @notice Withdraw all staked tokens (and collect reward tokens if requested)
     * @param claimRewardToken whether to claim reward tokens
     */
    function withdrawAll(bool claimRewardToken) external nonReentrant {
        _withdraw(userInfo[msg.sender].shares, claimRewardToken);
    }
    /**
     * @notice Update the reward per block (in rewardToken)
     * @dev Only callable by owner. Owner is meant to be another smart contract.
     */
    function updateRewards(uint256 reward, uint256 rewardDurationInBlocks) external onlyOwner {
        // Adjust the current reward per block
        if (block.number >= periodEndBlock) {
            currentRewardPerBlock = reward / rewardDurationInBlocks;
        } else {
            currentRewardPerBlock =
                (reward + ((periodEndBlock - block.number) * currentRewardPerBlock)) /
                rewardDurationInBlocks;
        }
        lastUpdateBlock = block.number;
        periodEndBlock = block.number + rewardDurationInBlocks;
        emit NewRewardPeriod(rewardDurationInBlocks, currentRewardPerBlock, reward);
    }
    /**
     * @notice Calculate pending rewards (WETH) for a user
     * @param user address of the user
     */
    function calculatePendingRewards(address user) external view returns (uint256) {
        return _calculatePendingRewards(user);
    }
    /**
     * @notice Calculate value of LOOKS for a user given a number of shares owned
     * @param user address of the user
     */
    function calculateSharesValueInLOOKS(address user) external view returns (uint256) {
        // Retrieve amount staked
        (uint256 totalAmountStaked, ) = tokenDistributor.userInfo(address(this));
        // Adjust for pending rewards
        totalAmountStaked += tokenDistributor.calculatePendingRewards(address(this));
        // Return user pro-rata of total shares
        return userInfo[user].shares == 0 ? 0 : (totalAmountStaked * userInfo[user].shares) / totalShares;
    }
    /**
     * @notice Calculate price of one share (in LOOKS token)
     * Share price is expressed times 1e18
     */
    function calculateSharePriceInLOOKS() external view returns (uint256) {
        (uint256 totalAmountStaked, ) = tokenDistributor.userInfo(address(this));
        // Adjust for pending rewards
        totalAmountStaked += tokenDistributor.calculatePendingRewards(address(this));
        return totalShares == 0 ? PRECISION_FACTOR : (totalAmountStaked * PRECISION_FACTOR) / (totalShares);
    }
    /**
     * @notice Return last block where trading rewards were distributed
     */
    function lastRewardBlock() external view returns (uint256) {
        return _lastRewardBlock();
    }
    /**
     * @notice Calculate pending rewards for a user
     * @param user address of the user
     */
    function _calculatePendingRewards(address user) internal view returns (uint256) {
        return
            ((userInfo[user].shares * (_rewardPerToken() - (userInfo[user].userRewardPerTokenPaid))) /
                PRECISION_FACTOR) + userInfo[user].rewards;
    }
    /**
     * @notice Check current allowance and adjust if necessary
     * @param _amount amount to transfer
     * @param _to token to transfer
     */
    function _checkAndAdjustLOOKSTokenAllowanceIfRequired(uint256 _amount, address _to) internal {
        if (looksRareToken.allowance(address(this), _to) < _amount) {
            looksRareToken.approve(_to, type(uint256).max);
        }
    }
    /**
     * @notice Return last block where rewards must be distributed
     */
    function _lastRewardBlock() internal view returns (uint256) {
        return block.number < periodEndBlock ? block.number : periodEndBlock;
    }
    /**
     * @notice Return reward per token
     */
    function _rewardPerToken() internal view returns (uint256) {
        if (totalShares == 0) {
            return rewardPerTokenStored;
        }
        return
            rewardPerTokenStored +
            ((_lastRewardBlock() - lastUpdateBlock) * (currentRewardPerBlock * PRECISION_FACTOR)) /
            totalShares;
    }
    /**
     * @notice Update reward for a user account
     * @param _user address of the user
     */
    function _updateReward(address _user) internal {
        if (block.number != lastUpdateBlock) {
            rewardPerTokenStored = _rewardPerToken();
            lastUpdateBlock = _lastRewardBlock();
        }
        userInfo[_user].rewards = _calculatePendingRewards(_user);
        userInfo[_user].userRewardPerTokenPaid = rewardPerTokenStored;
    }
    /**
     * @notice Withdraw staked tokens (and collect reward tokens if requested)
     * @param shares shares to withdraw
     * @param claimRewardToken whether to claim reward tokens
     */
    function _withdraw(uint256 shares, bool claimRewardToken) internal {
        // Auto compounds for everyone
        tokenDistributor.harvestAndCompound();
        // Update reward for user
        _updateReward(msg.sender);
        // Retrieve total amount staked and calculated current amount (in LOOKS)
        (uint256 totalAmountStaked, ) = tokenDistributor.userInfo(address(this));
        uint256 currentAmount = (totalAmountStaked * shares) / totalShares;
        userInfo[msg.sender].shares -= shares;
        totalShares -= shares;
        // Withdraw amount equivalent in shares
        tokenDistributor.withdraw(currentAmount);
        uint256 pendingRewards;
        if (claimRewardToken) {
            // Fetch pending rewards
            pendingRewards = userInfo[msg.sender].rewards;
            if (pendingRewards > 0) {
                userInfo[msg.sender].rewards = 0;
                rewardToken.safeTransfer(msg.sender, pendingRewards);
            }
        }
        // Transfer LOOKS tokens to sender
        looksRareToken.safeTransfer(msg.sender, currentAmount);
        emit Withdraw(msg.sender, currentAmount, pendingRewards);
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }
    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }
    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }
    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
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 making 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
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../IERC20.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 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'
        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) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    function safeDecreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _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
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import {IERC20, SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import {ILooksRareToken} from "../interfaces/ILooksRareToken.sol";
/**
 * @title TokenDistributor
 * @notice It handles the distribution of LOOKS token.
 * It auto-adjusts block rewards over a set number of periods.
 */
contract TokenDistributor is ReentrancyGuard {
    using SafeERC20 for IERC20;
    using SafeERC20 for ILooksRareToken;
    struct StakingPeriod {
        uint256 rewardPerBlockForStaking;
        uint256 rewardPerBlockForOthers;
        uint256 periodLengthInBlock;
    }
    struct UserInfo {
        uint256 amount; // Amount of staked tokens provided by user
        uint256 rewardDebt; // Reward debt
    }
    // Precision factor for calculating rewards
    uint256 public constant PRECISION_FACTOR = 10**12;
    ILooksRareToken public immutable looksRareToken;
    address public immutable tokenSplitter;
    // Number of reward periods
    uint256 public immutable NUMBER_PERIODS;
    // Block number when rewards start
    uint256 public immutable START_BLOCK;
    // Accumulated tokens per share
    uint256 public accTokenPerShare;
    // Current phase for rewards
    uint256 public currentPhase;
    // Block number when rewards end
    uint256 public endBlock;
    // Block number of the last update
    uint256 public lastRewardBlock;
    // Tokens distributed per block for other purposes (team + treasury + trading rewards)
    uint256 public rewardPerBlockForOthers;
    // Tokens distributed per block for staking
    uint256 public rewardPerBlockForStaking;
    // Total amount staked
    uint256 public totalAmountStaked;
    mapping(uint256 => StakingPeriod) public stakingPeriod;
    mapping(address => UserInfo) public userInfo;
    event Compound(address indexed user, uint256 harvestedAmount);
    event Deposit(address indexed user, uint256 amount, uint256 harvestedAmount);
    event NewRewardsPerBlock(
        uint256 indexed currentPhase,
        uint256 startBlock,
        uint256 rewardPerBlockForStaking,
        uint256 rewardPerBlockForOthers
    );
    event Withdraw(address indexed user, uint256 amount, uint256 harvestedAmount);
    /**
     * @notice Constructor
     * @param _looksRareToken LOOKS token address
     * @param _tokenSplitter token splitter contract address (for team and trading rewards)
     * @param _startBlock start block for reward program
     * @param _rewardsPerBlockForStaking array of rewards per block for staking
     * @param _rewardsPerBlockForOthers array of rewards per block for other purposes (team + treasury + trading rewards)
     * @param _periodLengthesInBlocks array of period lengthes
     * @param _numberPeriods number of periods with different rewards/lengthes (e.g., if 3 changes --> 4 periods)
     */
    constructor(
        address _looksRareToken,
        address _tokenSplitter,
        uint256 _startBlock,
        uint256[] memory _rewardsPerBlockForStaking,
        uint256[] memory _rewardsPerBlockForOthers,
        uint256[] memory _periodLengthesInBlocks,
        uint256 _numberPeriods
    ) {
        require(
            (_periodLengthesInBlocks.length == _numberPeriods) &&
                (_rewardsPerBlockForStaking.length == _numberPeriods) &&
                (_rewardsPerBlockForStaking.length == _numberPeriods),
            "Distributor: Lengthes must match numberPeriods"
        );
        // 1. Operational checks for supply
        uint256 nonCirculatingSupply = ILooksRareToken(_looksRareToken).SUPPLY_CAP() -
            ILooksRareToken(_looksRareToken).totalSupply();
        uint256 amountTokensToBeMinted;
        for (uint256 i = 0; i < _numberPeriods; i++) {
            amountTokensToBeMinted +=
                (_rewardsPerBlockForStaking[i] * _periodLengthesInBlocks[i]) +
                (_rewardsPerBlockForOthers[i] * _periodLengthesInBlocks[i]);
            stakingPeriod[i] = StakingPeriod({
                rewardPerBlockForStaking: _rewardsPerBlockForStaking[i],
                rewardPerBlockForOthers: _rewardsPerBlockForOthers[i],
                periodLengthInBlock: _periodLengthesInBlocks[i]
            });
        }
        require(amountTokensToBeMinted == nonCirculatingSupply, "Distributor: Wrong reward parameters");
        // 2. Store values
        looksRareToken = ILooksRareToken(_looksRareToken);
        tokenSplitter = _tokenSplitter;
        rewardPerBlockForStaking = _rewardsPerBlockForStaking[0];
        rewardPerBlockForOthers = _rewardsPerBlockForOthers[0];
        START_BLOCK = _startBlock;
        endBlock = _startBlock + _periodLengthesInBlocks[0];
        NUMBER_PERIODS = _numberPeriods;
        // Set the lastRewardBlock as the startBlock
        lastRewardBlock = _startBlock;
    }
    /**
     * @notice Deposit staked tokens and compounds pending rewards
     * @param amount amount to deposit (in LOOKS)
     */
    function deposit(uint256 amount) external nonReentrant {
        require(amount > 0, "Deposit: Amount must be > 0");
        // Update pool information
        _updatePool();
        // Transfer LOOKS tokens to this contract
        looksRareToken.safeTransferFrom(msg.sender, address(this), amount);
        uint256 pendingRewards;
        // If not new deposit, calculate pending rewards (for auto-compounding)
        if (userInfo[msg.sender].amount > 0) {
            pendingRewards =
                ((userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR) -
                userInfo[msg.sender].rewardDebt;
        }
        // Adjust user information
        userInfo[msg.sender].amount += (amount + pendingRewards);
        userInfo[msg.sender].rewardDebt = (userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR;
        // Increase totalAmountStaked
        totalAmountStaked += (amount + pendingRewards);
        emit Deposit(msg.sender, amount, pendingRewards);
    }
    /**
     * @notice Compound based on pending rewards
     */
    function harvestAndCompound() external nonReentrant {
        // Update pool information
        _updatePool();
        // Calculate pending rewards
        uint256 pendingRewards = ((userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR) -
            userInfo[msg.sender].rewardDebt;
        // Return if no pending rewards
        if (pendingRewards == 0) {
            // It doesn't throw revertion (to help with the fee-sharing auto-compounding contract)
            return;
        }
        // Adjust user amount for pending rewards
        userInfo[msg.sender].amount += pendingRewards;
        // Adjust totalAmountStaked
        totalAmountStaked += pendingRewards;
        // Recalculate reward debt based on new user amount
        userInfo[msg.sender].rewardDebt = (userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR;
        emit Compound(msg.sender, pendingRewards);
    }
    /**
     * @notice Update pool rewards
     */
    function updatePool() external nonReentrant {
        _updatePool();
    }
    /**
     * @notice Withdraw staked tokens and compound pending rewards
     * @param amount amount to withdraw
     */
    function withdraw(uint256 amount) external nonReentrant {
        require(
            (userInfo[msg.sender].amount >= amount) && (amount > 0),
            "Withdraw: Amount must be > 0 or lower than user balance"
        );
        // Update pool
        _updatePool();
        // Calculate pending rewards
        uint256 pendingRewards = ((userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR) -
            userInfo[msg.sender].rewardDebt;
        // Adjust user information
        userInfo[msg.sender].amount = userInfo[msg.sender].amount + pendingRewards - amount;
        userInfo[msg.sender].rewardDebt = (userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR;
        // Adjust total amount staked
        totalAmountStaked = totalAmountStaked + pendingRewards - amount;
        // Transfer LOOKS tokens to the sender
        looksRareToken.safeTransfer(msg.sender, amount);
        emit Withdraw(msg.sender, amount, pendingRewards);
    }
    /**
     * @notice Withdraw all staked tokens and collect tokens
     */
    function withdrawAll() external nonReentrant {
        require(userInfo[msg.sender].amount > 0, "Withdraw: Amount must be > 0");
        // Update pool
        _updatePool();
        // Calculate pending rewards and amount to transfer (to the sender)
        uint256 pendingRewards = ((userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR) -
            userInfo[msg.sender].rewardDebt;
        uint256 amountToTransfer = userInfo[msg.sender].amount + pendingRewards;
        // Adjust total amount staked
        totalAmountStaked = totalAmountStaked - userInfo[msg.sender].amount;
        // Adjust user information
        userInfo[msg.sender].amount = 0;
        userInfo[msg.sender].rewardDebt = 0;
        // Transfer LOOKS tokens to the sender
        looksRareToken.safeTransfer(msg.sender, amountToTransfer);
        emit Withdraw(msg.sender, amountToTransfer, pendingRewards);
    }
    /**
     * @notice Calculate pending rewards for a user
     * @param user address of the user
     * @return Pending rewards
     */
    function calculatePendingRewards(address user) external view returns (uint256) {
        if ((block.number > lastRewardBlock) && (totalAmountStaked != 0)) {
            uint256 multiplier = _getMultiplier(lastRewardBlock, block.number);
            uint256 tokenRewardForStaking = multiplier * rewardPerBlockForStaking;
            uint256 adjustedEndBlock = endBlock;
            uint256 adjustedCurrentPhase = currentPhase;
            // Check whether to adjust multipliers and reward per block
            while ((block.number > adjustedEndBlock) && (adjustedCurrentPhase < (NUMBER_PERIODS - 1))) {
                // Update current phase
                adjustedCurrentPhase++;
                // Update rewards per block
                uint256 adjustedRewardPerBlockForStaking = stakingPeriod[adjustedCurrentPhase].rewardPerBlockForStaking;
                // Calculate adjusted block number
                uint256 previousEndBlock = adjustedEndBlock;
                // Update end block
                adjustedEndBlock = previousEndBlock + stakingPeriod[adjustedCurrentPhase].periodLengthInBlock;
                // Calculate new multiplier
                uint256 newMultiplier = (block.number <= adjustedEndBlock)
                    ? (block.number - previousEndBlock)
                    : stakingPeriod[adjustedCurrentPhase].periodLengthInBlock;
                // Adjust token rewards for staking
                tokenRewardForStaking += (newMultiplier * adjustedRewardPerBlockForStaking);
            }
            uint256 adjustedTokenPerShare = accTokenPerShare +
                (tokenRewardForStaking * PRECISION_FACTOR) /
                totalAmountStaked;
            return (userInfo[user].amount * adjustedTokenPerShare) / PRECISION_FACTOR - userInfo[user].rewardDebt;
        } else {
            return (userInfo[user].amount * accTokenPerShare) / PRECISION_FACTOR - userInfo[user].rewardDebt;
        }
    }
    /**
     * @notice Update reward variables of the pool
     */
    function _updatePool() internal {
        if (block.number <= lastRewardBlock) {
            return;
        }
        if (totalAmountStaked == 0) {
            lastRewardBlock = block.number;
            return;
        }
        // Calculate multiplier
        uint256 multiplier = _getMultiplier(lastRewardBlock, block.number);
        // Calculate rewards for staking and others
        uint256 tokenRewardForStaking = multiplier * rewardPerBlockForStaking;
        uint256 tokenRewardForOthers = multiplier * rewardPerBlockForOthers;
        // Check whether to adjust multipliers and reward per block
        while ((block.number > endBlock) && (currentPhase < (NUMBER_PERIODS - 1))) {
            // Update rewards per block
            _updateRewardsPerBlock(endBlock);
            uint256 previousEndBlock = endBlock;
            // Adjust the end block
            endBlock += stakingPeriod[currentPhase].periodLengthInBlock;
            // Adjust multiplier to cover the missing periods with other lower inflation schedule
            uint256 newMultiplier = _getMultiplier(previousEndBlock, block.number);
            // Adjust token rewards
            tokenRewardForStaking += (newMultiplier * rewardPerBlockForStaking);
            tokenRewardForOthers += (newMultiplier * rewardPerBlockForOthers);
        }
        // Mint tokens only if token rewards for staking are not null
        if (tokenRewardForStaking > 0) {
            // It allows protection against potential issues to prevent funds from being locked
            bool mintStatus = looksRareToken.mint(address(this), tokenRewardForStaking);
            if (mintStatus) {
                accTokenPerShare = accTokenPerShare + ((tokenRewardForStaking * PRECISION_FACTOR) / totalAmountStaked);
            }
            looksRareToken.mint(tokenSplitter, tokenRewardForOthers);
        }
        // Update last reward block only if it wasn't updated after or at the end block
        if (lastRewardBlock <= endBlock) {
            lastRewardBlock = block.number;
        }
    }
    /**
     * @notice Update rewards per block
     * @dev Rewards are halved by 2 (for staking + others)
     */
    function _updateRewardsPerBlock(uint256 _newStartBlock) internal {
        // Update current phase
        currentPhase++;
        // Update rewards per block
        rewardPerBlockForStaking = stakingPeriod[currentPhase].rewardPerBlockForStaking;
        rewardPerBlockForOthers = stakingPeriod[currentPhase].rewardPerBlockForOthers;
        emit NewRewardsPerBlock(currentPhase, _newStartBlock, rewardPerBlockForStaking, rewardPerBlockForOthers);
    }
    /**
     * @notice Return reward multiplier over the given "from" to "to" block.
     * @param from block to start calculating reward
     * @param to block to finish calculating reward
     * @return the multiplier for the period
     */
    function _getMultiplier(uint256 from, uint256 to) internal view returns (uint256) {
        if (to <= endBlock) {
            return to - from;
        } else if (from >= endBlock) {
            return 0;
        } else {
            return endBlock - from;
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/IERC20.sol)
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
// OpenZeppelin Contracts v4.4.1 (utils/Address.sol)
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 {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
interface ILooksRareToken is IERC20 {
    function SUPPLY_CAP() external view returns (uint256);
    function mint(address account, uint256 amount) external returns (bool);
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
import {ERC20} from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import {ILooksRareToken} from "../interfaces/ILooksRareToken.sol";
/**
 * @title LooksRareToken (LOOKS)
 * @notice
LOOKSRARELOOKSRARELOOKSRLOOKSRARELOOKSRARELOOKSRARELOOKSRARELOOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRAR'''''''''''''''''''''''''''''''''''OOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKS:.                                        .;OOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOO,.                                            .,KSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRAREL'                ..',;:LOOKS::;,'..                'RARELOOKSRARELOOKSR
LOOKSRARELOOKSRAR.              .,:LOOKSRARELOOKSRARELO:,.              .RELOOKSRARELOOKSR
LOOKSRARELOOKS:.             .;RARELOOKSRARELOOKSRARELOOKSl;.             .:OOKSRARELOOKSR
LOOKSRARELOO;.            .'OKSRARELOOKSRARELOOKSRARELOOKSRARE'.            .;KSRARELOOKSR
LOOKSRAREL,.            .,LOOKSRARELOOK:;;:"""":;;;lELOOKSRARELO,.            .,RARELOOKSR
LOOKSRAR.             .;okLOOKSRAREx:.              .;OOKSRARELOOK;.             .RELOOKSR
LOOKS:.             .:dOOOLOOKSRARE'      .''''..     .OKSRARELOOKSR:.             .LOOKSR
LOx;.             .cKSRARELOOKSRAR'     'LOOKSRAR'     .KSRARELOOKSRARc..            .OKSR
L;.             .cxOKSRARELOOKSRAR.    .LOOKS.RARE'     ;kRARELOOKSRARExc.             .;R
LO'             .;oOKSRARELOOKSRAl.    .LOOKS.RARE.     :kRARELOOKSRAREo;.             'SR
LOOK;.            .,KSRARELOOKSRAx,     .;LOOKSR;.     .oSRARELOOKSRAo,.            .;OKSR
LOOKSk:.            .'RARELOOKSRARd;.      ....       'oOOOOOOOOOOxc'.            .:LOOKSR
LOOKSRARc.             .:dLOOKSRAREko;.            .,lxOOOOOOOOOd:.             .ARELOOKSR
LOOKSRARELo'             .;oOKSRARELOOxoc;,....,;:ldkOOOOOOOOkd;.             'SRARELOOKSR
LOOKSRARELOOd,.            .,lSRARELOOKSRARELOOKSRARELOOKSRkl,.            .,OKSRARELOOKSR
LOOKSRARELOOKSx;.            ..;oxELOOKSRARELOOKSRARELOkxl:..            .:LOOKSRARELOOKSR
LOOKSRARELOOKSRARc.              .':cOKSRARELOOKSRALOc;'.              .ARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELl'                 ...'',,,,''...                 'SRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOo,.                                          .,OKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSx;.                                      .;xOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLO:.                                  .:SRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKl.                              .lOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKSRo'.                        .'oLOOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKSRARd;.                    .;xRELOOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKSRARELO:.                .:kRARELOOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKSRARELOOKl.            .cOKSRARELOOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKSRARELOOKSRo'        'oLOOKSRARELOOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKSRARELOOKSRARE,.  .,dRELOOKSRARELOOKSRLOOKSRARELOOKSRARELOOKSR
LOOKSRARELOOKSRARELOOKSRLOOKSRARELOOKSRARELOOKSRARELOOKSRARELOOKSRLOOKSRARELOOKSRARELOOKSR
 */
contract LooksRareToken is ERC20, Ownable, ILooksRareToken {
    uint256 private immutable _SUPPLY_CAP;
    /**
     * @notice Constructor
     * @param _premintReceiver address that receives the premint
     * @param _premintAmount amount to premint
     * @param _cap supply cap (to prevent abusive mint)
     */
    constructor(
        address _premintReceiver,
        uint256 _premintAmount,
        uint256 _cap
    ) ERC20("LooksRare Token", "LOOKS") {
        require(_cap > _premintAmount, "LOOKS: Premint amount is greater than cap");
        // Transfer the sum of the premint to address
        _mint(_premintReceiver, _premintAmount);
        _SUPPLY_CAP = _cap;
    }
    /**
     * @notice Mint LOOKS tokens
     * @param account address to receive tokens
     * @param amount amount to mint
     * @return status true if mint is successful, false if not
     */
    function mint(address account, uint256 amount) external override onlyOwner returns (bool status) {
        if (totalSupply() + amount <= _SUPPLY_CAP) {
            _mint(account, amount);
            return true;
        }
        return false;
    }
    /**
     * @notice View supply cap
     */
    function SUPPLY_CAP() external view override returns (uint256) {
        return _SUPPLY_CAP;
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }
    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }
    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }
    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/ERC20.sol)
pragma solidity ^0.8.0;
import "./IERC20.sol";
import "./extensions/IERC20Metadata.sol";
import "../../utils/Context.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 Contracts guidelines: functions revert
 * instead 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, IERC20Metadata {
    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;
    uint256 private _totalSupply;
    string private _name;
    string private _symbol;
    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * The default value of {decimals} is 18. To select a different value for
     * {decimals} you should overload it.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }
    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }
    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual override 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 this function is
     * overridden;
     *
     * 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 virtual override returns (uint8) {
        return 18;
    }
    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }
    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual 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);
        uint256 currentAllowance = _allowances[sender][_msgSender()];
        require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
        unchecked {
            _approve(sender, _msgSender(), currentAllowance - amount);
        }
        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] + 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) {
        uint256 currentAllowance = _allowances[_msgSender()][spender];
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(_msgSender(), spender, currentAllowance - subtractedValue);
        }
        return true;
    }
    /**
     * @dev Moves `amount` of tokens from `sender` to `recipient`.
     *
     * This 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);
        uint256 senderBalance = _balances[sender];
        require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[sender] = senderBalance - amount;
        }
        _balances[recipient] += amount;
        emit Transfer(sender, recipient, amount);
        _afterTokenTransfer(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:
     *
     * - `account` 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 += amount;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);
        _afterTokenTransfer(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);
        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
        }
        _totalSupply -= amount;
        emit Transfer(account, address(0), amount);
        _afterTokenTransfer(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 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 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 {}
    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * has been transferred to `to`.
     * - when `from` is zero, `amount` tokens have been minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens have been 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 _afterTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
interface ILooksRareToken is IERC20 {
    function SUPPLY_CAP() external view returns (uint256);
    function mint(address account, uint256 amount) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/IERC20.sol)
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
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);
    /**
     * @dev Returns the symbol of the token.
     */
    function symbol() external view returns (string memory);
    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import {IERC20, SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import {ILooksRareToken} from "../interfaces/ILooksRareToken.sol";
/**
 * @title TokenDistributor
 * @notice It handles the distribution of LOOKS token.
 * It auto-adjusts block rewards over a set number of periods.
 */
contract TokenDistributor is ReentrancyGuard {
    using SafeERC20 for IERC20;
    using SafeERC20 for ILooksRareToken;
    struct StakingPeriod {
        uint256 rewardPerBlockForStaking;
        uint256 rewardPerBlockForOthers;
        uint256 periodLengthInBlock;
    }
    struct UserInfo {
        uint256 amount; // Amount of staked tokens provided by user
        uint256 rewardDebt; // Reward debt
    }
    // Precision factor for calculating rewards
    uint256 public constant PRECISION_FACTOR = 10**12;
    ILooksRareToken public immutable looksRareToken;
    address public immutable tokenSplitter;
    // Number of reward periods
    uint256 public immutable NUMBER_PERIODS;
    // Block number when rewards start
    uint256 public immutable START_BLOCK;
    // Accumulated tokens per share
    uint256 public accTokenPerShare;
    // Current phase for rewards
    uint256 public currentPhase;
    // Block number when rewards end
    uint256 public endBlock;
    // Block number of the last update
    uint256 public lastRewardBlock;
    // Tokens distributed per block for other purposes (team + treasury + trading rewards)
    uint256 public rewardPerBlockForOthers;
    // Tokens distributed per block for staking
    uint256 public rewardPerBlockForStaking;
    // Total amount staked
    uint256 public totalAmountStaked;
    mapping(uint256 => StakingPeriod) public stakingPeriod;
    mapping(address => UserInfo) public userInfo;
    event Compound(address indexed user, uint256 harvestedAmount);
    event Deposit(address indexed user, uint256 amount, uint256 harvestedAmount);
    event NewRewardsPerBlock(
        uint256 indexed currentPhase,
        uint256 startBlock,
        uint256 rewardPerBlockForStaking,
        uint256 rewardPerBlockForOthers
    );
    event Withdraw(address indexed user, uint256 amount, uint256 harvestedAmount);
    /**
     * @notice Constructor
     * @param _looksRareToken LOOKS token address
     * @param _tokenSplitter token splitter contract address (for team and trading rewards)
     * @param _startBlock start block for reward program
     * @param _rewardsPerBlockForStaking array of rewards per block for staking
     * @param _rewardsPerBlockForOthers array of rewards per block for other purposes (team + treasury + trading rewards)
     * @param _periodLengthesInBlocks array of period lengthes
     * @param _numberPeriods number of periods with different rewards/lengthes (e.g., if 3 changes --> 4 periods)
     */
    constructor(
        address _looksRareToken,
        address _tokenSplitter,
        uint256 _startBlock,
        uint256[] memory _rewardsPerBlockForStaking,
        uint256[] memory _rewardsPerBlockForOthers,
        uint256[] memory _periodLengthesInBlocks,
        uint256 _numberPeriods
    ) {
        require(
            (_periodLengthesInBlocks.length == _numberPeriods) &&
                (_rewardsPerBlockForStaking.length == _numberPeriods) &&
                (_rewardsPerBlockForStaking.length == _numberPeriods),
            "Distributor: Lengthes must match numberPeriods"
        );
        // 1. Operational checks for supply
        uint256 nonCirculatingSupply = ILooksRareToken(_looksRareToken).SUPPLY_CAP() -
            ILooksRareToken(_looksRareToken).totalSupply();
        uint256 amountTokensToBeMinted;
        for (uint256 i = 0; i < _numberPeriods; i++) {
            amountTokensToBeMinted +=
                (_rewardsPerBlockForStaking[i] * _periodLengthesInBlocks[i]) +
                (_rewardsPerBlockForOthers[i] * _periodLengthesInBlocks[i]);
            stakingPeriod[i] = StakingPeriod({
                rewardPerBlockForStaking: _rewardsPerBlockForStaking[i],
                rewardPerBlockForOthers: _rewardsPerBlockForOthers[i],
                periodLengthInBlock: _periodLengthesInBlocks[i]
            });
        }
        require(amountTokensToBeMinted == nonCirculatingSupply, "Distributor: Wrong reward parameters");
        // 2. Store values
        looksRareToken = ILooksRareToken(_looksRareToken);
        tokenSplitter = _tokenSplitter;
        rewardPerBlockForStaking = _rewardsPerBlockForStaking[0];
        rewardPerBlockForOthers = _rewardsPerBlockForOthers[0];
        START_BLOCK = _startBlock;
        endBlock = _startBlock + _periodLengthesInBlocks[0];
        NUMBER_PERIODS = _numberPeriods;
        // Set the lastRewardBlock as the startBlock
        lastRewardBlock = _startBlock;
    }
    /**
     * @notice Deposit staked tokens and compounds pending rewards
     * @param amount amount to deposit (in LOOKS)
     */
    function deposit(uint256 amount) external nonReentrant {
        require(amount > 0, "Deposit: Amount must be > 0");
        // Update pool information
        _updatePool();
        // Transfer LOOKS tokens to this contract
        looksRareToken.safeTransferFrom(msg.sender, address(this), amount);
        uint256 pendingRewards;
        // If not new deposit, calculate pending rewards (for auto-compounding)
        if (userInfo[msg.sender].amount > 0) {
            pendingRewards =
                ((userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR) -
                userInfo[msg.sender].rewardDebt;
        }
        // Adjust user information
        userInfo[msg.sender].amount += (amount + pendingRewards);
        userInfo[msg.sender].rewardDebt = (userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR;
        // Increase totalAmountStaked
        totalAmountStaked += (amount + pendingRewards);
        emit Deposit(msg.sender, amount, pendingRewards);
    }
    /**
     * @notice Compound based on pending rewards
     */
    function harvestAndCompound() external nonReentrant {
        // Update pool information
        _updatePool();
        // Calculate pending rewards
        uint256 pendingRewards = ((userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR) -
            userInfo[msg.sender].rewardDebt;
        // Return if no pending rewards
        if (pendingRewards == 0) {
            // It doesn't throw revertion (to help with the fee-sharing auto-compounding contract)
            return;
        }
        // Adjust user amount for pending rewards
        userInfo[msg.sender].amount += pendingRewards;
        // Adjust totalAmountStaked
        totalAmountStaked += pendingRewards;
        // Recalculate reward debt based on new user amount
        userInfo[msg.sender].rewardDebt = (userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR;
        emit Compound(msg.sender, pendingRewards);
    }
    /**
     * @notice Update pool rewards
     */
    function updatePool() external nonReentrant {
        _updatePool();
    }
    /**
     * @notice Withdraw staked tokens and compound pending rewards
     * @param amount amount to withdraw
     */
    function withdraw(uint256 amount) external nonReentrant {
        require(
            (userInfo[msg.sender].amount >= amount) && (amount > 0),
            "Withdraw: Amount must be > 0 or lower than user balance"
        );
        // Update pool
        _updatePool();
        // Calculate pending rewards
        uint256 pendingRewards = ((userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR) -
            userInfo[msg.sender].rewardDebt;
        // Adjust user information
        userInfo[msg.sender].amount = userInfo[msg.sender].amount + pendingRewards - amount;
        userInfo[msg.sender].rewardDebt = (userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR;
        // Adjust total amount staked
        totalAmountStaked = totalAmountStaked + pendingRewards - amount;
        // Transfer LOOKS tokens to the sender
        looksRareToken.safeTransfer(msg.sender, amount);
        emit Withdraw(msg.sender, amount, pendingRewards);
    }
    /**
     * @notice Withdraw all staked tokens and collect tokens
     */
    function withdrawAll() external nonReentrant {
        require(userInfo[msg.sender].amount > 0, "Withdraw: Amount must be > 0");
        // Update pool
        _updatePool();
        // Calculate pending rewards and amount to transfer (to the sender)
        uint256 pendingRewards = ((userInfo[msg.sender].amount * accTokenPerShare) / PRECISION_FACTOR) -
            userInfo[msg.sender].rewardDebt;
        uint256 amountToTransfer = userInfo[msg.sender].amount + pendingRewards;
        // Adjust total amount staked
        totalAmountStaked = totalAmountStaked - userInfo[msg.sender].amount;
        // Adjust user information
        userInfo[msg.sender].amount = 0;
        userInfo[msg.sender].rewardDebt = 0;
        // Transfer LOOKS tokens to the sender
        looksRareToken.safeTransfer(msg.sender, amountToTransfer);
        emit Withdraw(msg.sender, amountToTransfer, pendingRewards);
    }
    /**
     * @notice Calculate pending rewards for a user
     * @param user address of the user
     * @return Pending rewards
     */
    function calculatePendingRewards(address user) external view returns (uint256) {
        if ((block.number > lastRewardBlock) && (totalAmountStaked != 0)) {
            uint256 multiplier = _getMultiplier(lastRewardBlock, block.number);
            uint256 tokenRewardForStaking = multiplier * rewardPerBlockForStaking;
            uint256 adjustedEndBlock = endBlock;
            uint256 adjustedCurrentPhase = currentPhase;
            // Check whether to adjust multipliers and reward per block
            while ((block.number > adjustedEndBlock) && (adjustedCurrentPhase < (NUMBER_PERIODS - 1))) {
                // Update current phase
                adjustedCurrentPhase++;
                // Update rewards per block
                uint256 adjustedRewardPerBlockForStaking = stakingPeriod[adjustedCurrentPhase].rewardPerBlockForStaking;
                // Calculate adjusted block number
                uint256 previousEndBlock = adjustedEndBlock;
                // Update end block
                adjustedEndBlock = previousEndBlock + stakingPeriod[adjustedCurrentPhase].periodLengthInBlock;
                // Calculate new multiplier
                uint256 newMultiplier = (block.number <= adjustedEndBlock)
                    ? (block.number - previousEndBlock)
                    : stakingPeriod[adjustedCurrentPhase].periodLengthInBlock;
                // Adjust token rewards for staking
                tokenRewardForStaking += (newMultiplier * adjustedRewardPerBlockForStaking);
            }
            uint256 adjustedTokenPerShare = accTokenPerShare +
                (tokenRewardForStaking * PRECISION_FACTOR) /
                totalAmountStaked;
            return (userInfo[user].amount * adjustedTokenPerShare) / PRECISION_FACTOR - userInfo[user].rewardDebt;
        } else {
            return (userInfo[user].amount * accTokenPerShare) / PRECISION_FACTOR - userInfo[user].rewardDebt;
        }
    }
    /**
     * @notice Update reward variables of the pool
     */
    function _updatePool() internal {
        if (block.number <= lastRewardBlock) {
            return;
        }
        if (totalAmountStaked == 0) {
            lastRewardBlock = block.number;
            return;
        }
        // Calculate multiplier
        uint256 multiplier = _getMultiplier(lastRewardBlock, block.number);
        // Calculate rewards for staking and others
        uint256 tokenRewardForStaking = multiplier * rewardPerBlockForStaking;
        uint256 tokenRewardForOthers = multiplier * rewardPerBlockForOthers;
        // Check whether to adjust multipliers and reward per block
        while ((block.number > endBlock) && (currentPhase < (NUMBER_PERIODS - 1))) {
            // Update rewards per block
            _updateRewardsPerBlock(endBlock);
            uint256 previousEndBlock = endBlock;
            // Adjust the end block
            endBlock += stakingPeriod[currentPhase].periodLengthInBlock;
            // Adjust multiplier to cover the missing periods with other lower inflation schedule
            uint256 newMultiplier = _getMultiplier(previousEndBlock, block.number);
            // Adjust token rewards
            tokenRewardForStaking += (newMultiplier * rewardPerBlockForStaking);
            tokenRewardForOthers += (newMultiplier * rewardPerBlockForOthers);
        }
        // Mint tokens only if token rewards for staking are not null
        if (tokenRewardForStaking > 0) {
            // It allows protection against potential issues to prevent funds from being locked
            bool mintStatus = looksRareToken.mint(address(this), tokenRewardForStaking);
            if (mintStatus) {
                accTokenPerShare = accTokenPerShare + ((tokenRewardForStaking * PRECISION_FACTOR) / totalAmountStaked);
            }
            looksRareToken.mint(tokenSplitter, tokenRewardForOthers);
        }
        // Update last reward block only if it wasn't updated after or at the end block
        if (lastRewardBlock <= endBlock) {
            lastRewardBlock = block.number;
        }
    }
    /**
     * @notice Update rewards per block
     * @dev Rewards are halved by 2 (for staking + others)
     */
    function _updateRewardsPerBlock(uint256 _newStartBlock) internal {
        // Update current phase
        currentPhase++;
        // Update rewards per block
        rewardPerBlockForStaking = stakingPeriod[currentPhase].rewardPerBlockForStaking;
        rewardPerBlockForOthers = stakingPeriod[currentPhase].rewardPerBlockForOthers;
        emit NewRewardsPerBlock(currentPhase, _newStartBlock, rewardPerBlockForStaking, rewardPerBlockForOthers);
    }
    /**
     * @notice Return reward multiplier over the given "from" to "to" block.
     * @param from block to start calculating reward
     * @param to block to finish calculating reward
     * @return the multiplier for the period
     */
    function _getMultiplier(uint256 from, uint256 to) internal view returns (uint256) {
        if (to <= endBlock) {
            return to - from;
        } else if (from >= endBlock) {
            return 0;
        } else {
            return endBlock - from;
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
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 making 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
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../IERC20.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 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'
        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) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    function safeDecreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _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
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
interface ILooksRareToken is IERC20 {
    function SUPPLY_CAP() external view returns (uint256);
    function mint(address account, uint256 amount) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/IERC20.sol)
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
// OpenZeppelin Contracts v4.4.1 (utils/Address.sol)
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);
            }
        }
    }
}