build: tokenized staker

src/Bases/Staker/ITokenizedStaker.sol

@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: AGPL-3.0
+pragma solidity ^0.8.18;
+
+import {IStrategy} from "@tokenized-strategy/interfaces/IStrategy.sol";
+
+interface ITokenizedStaker is IStrategy {
+    /* ========== EVENTS ========== */
+    event RewardAdded(uint256 reward);
+    event RewardPaid(address indexed user, uint256 reward);
+    event RewardsDurationUpdated(uint256 newDuration);
+
+    /* ========== STATE VARIABLES ========== */
+    function rewardToken() external view returns (address);
+
+    function periodFinish() external view returns (uint256);
+
+    function rewardRate() external view returns (uint256);
+
+    function rewardsDuration() external view returns (uint256);
+
+    function lastUpdateTime() external view returns (uint256);
+
+    function rewardPerTokenStored() external view returns (uint256);
+
+    function userRewardPerTokenPaid(
+        address account
+    ) external view returns (uint256);
+
+    function rewards(address account) external view returns (uint256);
+
+    /* ========== FUNCTIONS ========== */
+    function lastTimeRewardApplicable() external view returns (uint256);
+
+    function rewardPerToken() external view returns (uint256);
+
+    function earned(address account) external view returns (uint256);
+
+    function getRewardForDuration() external view returns (uint256);
+
+    function notifyRewardAmount(uint256 reward) external;
+
+    function getReward() external;
+
+    function exit() external;
+
+    function setRewardsDuration(uint256 _rewardsDuration) external;
+}

src/Bases/Staker/TokenizedStaker.sol

@@ -0,0 +1,209 @@
+// SPDX-License-Identifier: AGPL-3.0
+pragma solidity ^0.8.18;
+
+import {BaseHooks, ERC20} from "../Hooks/BaseHooks.sol";
+import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
+import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
+
+abstract contract TokenizedStaker is BaseHooks, ReentrancyGuard {
+    using SafeERC20 for ERC20;
+
+    /* ========== EVENTS ========== */
+
+    event RewardAdded(uint256 reward);
+    event RewardPaid(address indexed user, uint256 reward);
+    event RewardsDurationUpdated(uint256 newDuration);
+
+    /* ========== MODIFIERS ========== */
+
+    modifier updateReward(address account) {
+        _updateReward(account);
+        _;
+    }
+
+    function _updateReward(address account) internal virtual {
+        rewardPerTokenStored = rewardPerToken();
+        lastUpdateTime = lastTimeRewardApplicable();
+        if (account != address(0)) {
+            rewards[account] = earned(account);
+            userRewardPerTokenPaid[account] = rewardPerTokenStored;
+        }
+    }
+
+    ERC20 public immutable rewardToken;
+
+    uint256 public periodFinish;
+
+    /// @notice The distribution rate of rewardToken per second.
+    uint256 public rewardRate;
+
+    /// @notice The duration of our rewards distribution for staking, default is 7 days.
+    uint256 public rewardsDuration = 7 days;
+
+    /// @notice The last time rewards were updated, triggered by updateReward() or notifyRewardAmount().
+    /// @dev Will be the timestamp of the update or the end of the period, whichever is earlier.
+    uint256 public lastUpdateTime;
+
+    /// @notice The most recent stored amount for rewardPerToken().
+    /// @dev Updated every time anyone calls the updateReward() modifier.
+    uint256 public rewardPerTokenStored;
+
+    // @notice The amount of rewards allocated to a user per whole token staked.
+    /// @dev Note that this is not the same as amount of rewards claimed.
+    mapping(address => uint256) public userRewardPerTokenPaid;
+
+    /// @notice The amount of unclaimed rewards an account is owed.
+    mapping(address => uint256) public rewards;
+
+    constructor(
+        address _asset,
+        string memory _name,
+        address _rewardToken
+    ) BaseHooks(_asset, _name) {
+        rewardToken = ERC20(_rewardToken);
+    }
+
+    function _preDepositHook(
+        uint256 /* assets */,
+        uint256 /* shares */,
+        address receiver
+    ) internal virtual override {
+        _updateReward(receiver);
+    }
+
+    function _preWithdrawHook(
+        uint256 /* assets */,
+        uint256 /* shares */,
+        address /* receiver */,
+        address owner,
+        uint256 /* maxLoss */
+    ) internal virtual override {
+        _updateReward(owner);
+    }
+
+    function _preTransferHook(
+        address from,
+        address to,
+        uint256 /* amount */
+    ) internal virtual override {
+        _updateReward(from);
+        _updateReward(to);
+    }
+
+    /// @notice Either the current timestamp or end of the most recent period.
+    function lastTimeRewardApplicable() public view virtual returns (uint256) {
+        return block.timestamp < periodFinish ? block.timestamp : periodFinish;
+    }
+
+    /// @notice Reward paid out per whole token.
+    function rewardPerToken() public view virtual returns (uint256) {
+        uint256 _totalSupply = TokenizedStrategy.totalSupply();
+        if (_totalSupply == 0) {
+            return rewardPerTokenStored;
+        }
+
+        if (TokenizedStrategy.isShutdown()) {
+            return 0;
+        }
+
+        return
+            rewardPerTokenStored +
+            (((lastTimeRewardApplicable() - lastUpdateTime) *
+                rewardRate *
+                1e18) / _totalSupply);
+    }
+
+    /// @notice Amount of reward token pending claim by an account.
+    function earned(address account) public view virtual returns (uint256) {
+        if (TokenizedStrategy.isShutdown()) {
+            return 0;
+        }
+
+        return
+            (TokenizedStrategy.balanceOf(account) *
+                (rewardPerToken() - userRewardPerTokenPaid[account])) /
+            1e18 +
+            rewards[account];
+    }
+
+    /// @notice Reward tokens emitted over the entire rewardsDuration.
+    function getRewardForDuration() external view virtual returns (uint256) {
+        return rewardRate * rewardsDuration;
+    }
+
+    function notifyRewardAmount(
+        uint256 reward
+    ) external virtual onlyManagement {
+        _notifyRewardAmount(reward);
+    }
+
+    /// @notice Notify staking contract that it has more reward to account for.
+    /// @dev Reward tokens must be sent to contract before notifying. May only be called
+    ///  by rewards distribution role.
+    /// @param reward Amount of reward tokens to add.
+    function _notifyRewardAmount(
+        uint256 reward
+    ) internal virtual updateReward(address(0)) {
+        if (block.timestamp >= periodFinish) {
+            rewardRate = reward / rewardsDuration;
+        } else {
+            uint256 remaining = periodFinish - block.timestamp;
+            uint256 leftover = remaining * rewardRate;
+            rewardRate = reward + leftover / rewardsDuration;
+        }
+
+        // Ensure the provided reward amount is not more than the balance in the contract.
+        // This keeps the reward rate in the right range, preventing overflows due to
+        // very high values of rewardRate in the earned and rewardsPerToken functions;
+        // Reward + leftover must be less than 2^256 / 10^18 to avoid overflow.
+        uint256 balance = rewardToken.balanceOf(address(this));
+        require(
+            rewardRate <= balance / rewardsDuration,
+            "Provided reward too high"
+        );
+
+        lastUpdateTime = block.timestamp;
+        periodFinish = block.timestamp + rewardsDuration;
+        emit RewardAdded(reward);
+    }
+
+    /// @notice Claim any earned reward tokens.
+    /// @dev Can claim rewards even if no tokens still staked.
+    function getReward() public virtual nonReentrant updateReward(msg.sender) {
+        uint256 reward = rewards[msg.sender];
+        if (reward > 0) {
+            rewards[msg.sender] = 0;
+            rewardToken.safeTransfer(msg.sender, reward);
+            emit RewardPaid(msg.sender, reward);
+        }
+    }
+
+    /// @notice Unstake all of the sender's tokens and claim any outstanding rewards.
+    function exit() external virtual {
+        redeem(
+            TokenizedStrategy.balanceOf(msg.sender),
+            msg.sender,
+            msg.sender,
+            10_000
+        );
+        getReward();
+    }
+
+    /// @notice Set the duration of our rewards period.
+    /// @dev May only be called by owner, and must be done after most recent period ends.
+    /// @param _rewardsDuration New length of period in seconds.
+    function setRewardsDuration(
+        uint256 _rewardsDuration
+    ) external virtual onlyManagement {
+        _setRewardsDuration(_rewardsDuration);
+    }
+
+    function _setRewardsDuration(uint256 _rewardsDuration) internal virtual {
+        require(
+            block.timestamp > periodFinish,
+            "Previous rewards period must be complete before changing the duration for the new period"
+        );
+        rewardsDuration = _rewardsDuration;
+        emit RewardsDurationUpdated(rewardsDuration);
+    }
+}