// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)

pragma solidity ^0.8.1;

/**
 * @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
     *
     * Furthermore, `isContract` will also return true if the target contract within
     * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
     * which only has an effect at the end of a transaction.
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 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://consensys.net/diligence/blog/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/v0.8.0/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 functionCallWithValue(target, data, 0, "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");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, 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) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, 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) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or 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 {
            _revert(returndata, errorMessage);
        }
    }

    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // 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
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (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;
    }

    function _contextSuffixLength() internal view virtual returns (uint256) {
        return 0;
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

// Import OpenZeppelin contracts
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol";
import "./PZENPZICPriceLib.sol"; // Import the new library
/**
 * @title Eth4
 * @dev A staking contract that allows users to deposit PLP tokens and earn rewards in PZIC tokens.
 *      The contract calculates the PZEN equivalent of the deposited PLP tokens using on-chain data,
 *      accounting for the different decimal places of PZEN (9 decimals), PZIC (18 decimals), and PLP (18 decimals).
 *      Includes a tolerance in the withdraw function to account for minor discrepancies.
 *      Allows the owner to set the time unit for testing or production.
 */
 interface IPulseLiquidityPool {
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function token0() external view returns (address);
    function token1() external view returns (address);
}


contract Eth4 is Ownable, ReentrancyGuard {
    using SafeERC20 for IERC20;
    using PZENPZICPriceLib for PZENPZICPriceLib.Observation[24];
  event TimeUnitUpdated(uint256 oldTimeUnit, uint256 newTimeUnit);
//record values
event RewardCalculationDetails(
    uint256 indexed pid,
    address indexed user,
    uint256 pzenEquivalent,
    uint256 periodsPassed,
    uint256 reward,
    uint256 pzenPzicRatio,
    uint256 finalPzicReward
);
// Add this struct definition near the top of your contract
event ObservationUpdated(uint256 timestamp, uint256 reservePZEN, uint256 totalSupply, uint32 blockTimestampLast);

struct Notification {
    uint256 poolID;
    uint256 amount;
    address user;
    string typeOf;
    uint256 timestamp;
}

    struct UserInfo {
        uint256 amount;           // PLP tokens deposited (18 decimals)
        uint256 pzenEquivalent;   // PZEN equivalent (9 decimals)
        uint256 lastRewardAt;     // Timestamp of last reward calculation
        uint256 lockUntil;        // Timestamp until which funds are locked
    }

    struct PoolInfo {
         uint256 poolID;  // New field
         IERC20 depositToken;      // Deposit token (PLP)
        IERC20 rewardToken;       // Reward token (PZIC)
        uint256 depositedAmount;  // Total deposited in pool (18 decimals)
        uint256 apy;              // Annual Percentage Yield (e.g., 10 for 10%)
        uint256 lockDays;         // Lock duration in days
    }

    uint256 public timeUnit;
Notification[] public notifications;
    // Token decimals to remove
   // uint8 constant PZEN_DECIMALS = 9;    // PZEN token decimals
    //uint8 constant PZIC_DECIMALS = 18;   // PZIC token decimals
   // uint8 constant PLP_DECIMALS = 18;    // PLP token decimals

    address public pzenTokenAddress;     // PZEN token address
    address public plpTokenAddress;      // PLP token address

    IPulseLiquidityPool public plpContract; // Interface for PLP contract

    uint256 public poolCount;            // Total number of pools
    PoolInfo[] public poolInfo;          // Array of pool information

    mapping(uint256 => mapping(address => UserInfo)) public userInfo; // User information per pool

    event Deposit(address indexed user, uint256 indexed pid, uint256 amount, uint256 pzenEquivalent);
    event Withdraw(address indexed user, uint256 indexed pid, uint256 amount, uint256 pzenEquivalent);
    event Claim(address indexed user, uint256 indexed pid, uint256 amount);
    event InsufficientRewardTokens(uint256 indexed pid, uint256 requestedAmount, uint256 availableAmount);
event PendingRewardCalculated(uint256 indexed pid, uint256 reward, uint256 adjustedReward);
// Add these struct and state variables near the top of your contract
struct Observation {
    uint256 timestamp;
    uint256 reservePZEN;
    uint256 totalSupply;
}

Observation[] public observations;
uint256 public constant OBSERVATION_PERIOD = 1 hours;
uint256 public constant MAX_OBSERVATIONS = 24; // Store up to 24 hours of hourly prices
  // Add this constructor after the state variables
   IPZENPZICPool public immutable pzenPzicPool;
    PZENPZICPriceLib.Observation[24] private priceObservations;
    uint256 private observationIndex;
    uint256 private observationCardinality;

    constructor(
        address _plpTokenAddress,
         address _pzenTokenAddress, 
         uint256 _initialTimeUnit,
         address _pzenPzicPoolAddress
         ) 
         {
        require(_plpTokenAddress != address(0), "Invalid PLP token address");
        require(_pzenTokenAddress != address(0), "Invalid PZEN token address");
        require(_initialTimeUnit >= 60, "Initial time unit must be at least 60 seconds");
    pzenPzicPool = IPZENPZICPool(_pzenPzicPoolAddress);
        plpTokenAddress = _plpTokenAddress;
        pzenTokenAddress = _pzenTokenAddress;
        plpContract = IPulseLiquidityPool(_plpTokenAddress);
        timeUnit = _initialTimeUnit;
         // Initialize the first observation
        (observationIndex, observationCardinality) = PZENPZICPriceLib.updateObservation(
            pzenPzicPool,
            pzenTokenAddress,
            priceObservations,
            observationIndex,
            observationCardinality
        );
    }
// Add this function to update observations
//newfunctioncall
function initializeObservation() public onlyOwner {
    require(observations.length == 0, "Observations already initialized");
    updateObservation();
}
//endofinitialise
function updateObservation() internal {
    bool shouldUpdate;
    if (observations.length > 0) {
        shouldUpdate = block.timestamp - observations[observations.length - 1].timestamp >= OBSERVATION_PERIOD;
    } else {
        shouldUpdate = true;
    }

    if (shouldUpdate) {
        (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast) = plpContract.getReserves();
        // We're capturing blockTimestampLast to satisfy Slither, but not using it directly
        // Example of logging blockTimestampLast to use the variable


        uint256 reservePZEN = plpContract.token0() == pzenTokenAddress ? uint256(reserve0) : uint256(reserve1);
        uint256 totalSupply = IERC20(plpTokenAddress).totalSupply();

        if (observations.length > 0) {
            if (observations.length >= MAX_OBSERVATIONS) {
                for (uint i = 0; i < observations.length - 1; i++) {
                    observations[i] = observations[i + 1];
                }
                observations[observations.length - 1] = Observation(block.timestamp, reservePZEN, totalSupply);
            } else {
                observations.push(Observation(block.timestamp, reservePZEN, totalSupply));
            }
        } else {
            observations.push(Observation(block.timestamp, reservePZEN, totalSupply));
        }
   emit ObservationUpdated(block.timestamp, reservePZEN, totalSupply, blockTimestampLast); }
}
   //new function
    function getPzenPzicRatio() public view returns (uint256) {
    return PZENPZICPriceLib.calculateTWAP(
        pzenPzicPool,
        pzenTokenAddress,
        priceObservations,
        observationIndex,
        observationCardinality
    );
}
//function sweep
    function sweep(address token, uint256 amount) external onlyOwner {
        uint256 tokenBalance = IERC20(token).balanceOf(address(this));
        require(amount <= tokenBalance, "Amount exceeds balance");

        // Ensure the token is a reward token in at least one pool
        bool isRewardToken = false;
        uint256 poolInfoLength = poolInfo.length;
        for (uint256 i = 0; i < poolInfoLength; i++) {
            if (address(poolInfo[i].rewardToken) == token) {
                isRewardToken = true;
                break;
            }
        }
        require(isRewardToken, "Token is not a reward token");

        // Transfer the specified amount of reward tokens to the owner
        IERC20(token).safeTransfer(msg.sender, amount);
    }
// Modify the calculatePzenEquivalent function to use TWAP
function calculatePzenEquivalent(uint256 _plpAmount) public view returns (uint256) {
    require(observations.length > 0, "No price data available");
    
    if (observations.length <= 1) {
        // If we only have one observation, use it directly
        uint256 reservePZEN = observations[0].reservePZEN;
        uint256 totalSupply = observations[0].totalSupply;
        uint256 calculatedPzenEquivalent = (_plpAmount * reservePZEN) / totalSupply;
        return calculatedPzenEquivalent;
    }

    uint256 timeWeightedReservePZEN = 0;
    uint256 timeWeightedTotalSupply = 0;
    uint256 timeSum = 0;
    uint256 startIndex = 0;

    // Find the starting index for observations within OBSERVATION_PERIOD
    for (uint i = observations.length - 1; i > 0; i--) {
        if (block.timestamp - observations[i].timestamp > OBSERVATION_PERIOD) {
            startIndex = i + 1;
            break;
        }
    }

    // Ensure we have at least two observations for TWAP
    if (startIndex >= observations.length - 1) {
        startIndex = observations.length > 1 ? observations.length - 2 : 0;
    }
uint256 observationsLength = observations.length;
    for (uint i = startIndex; i < observationsLength; i++) {
        uint256 timeInterval;
        if (i >= observations.length - 1) {
            timeInterval = block.timestamp - observations[i].timestamp;
        } else {
            timeInterval = observations[i + 1].timestamp - observations[i].timestamp;
        }
        timeWeightedReservePZEN += observations[i].reservePZEN * timeInterval;
        timeWeightedTotalSupply += observations[i].totalSupply * timeInterval;
        timeSum += timeInterval;
    }

    if (timeSum <= 0) {
        // If we don't have enough data for TWAP, use the latest observation
        timeWeightedReservePZEN = observations[observations.length - 1].reservePZEN;
        timeWeightedTotalSupply = observations[observations.length - 1].totalSupply;
        timeSum = 1;
    }

    //uint256 averageReservePZEN = timeWeightedReservePZEN / timeSum;
   // uint256 averageTotalSupply = timeWeightedTotalSupply / timeSum;

    // Calculate PZEN equivalent using TWAP values
     uint256 pzenEquivalent = (_plpAmount * timeWeightedReservePZEN) / timeWeightedTotalSupply;

    // Convert to 9 decimals (PZEN decimals)
    //pzenEquivalent = pzenEquivalent * (10 ** (PLP_DECIMALS - PZEN_DECIMALS));

    return pzenEquivalent;
}
function checkRewardTokenBalance(uint256 _pid, uint256 _amount) internal view returns (bool) {
    PoolInfo storage pool = poolInfo[_pid];
    return pool.rewardToken.balanceOf(address(this)) >= _amount;
}
// Modify the deposit function to include updateObservation
function deposit(uint256 _pid, uint256 _amount) public nonReentrant {
    require(_pid < poolInfo.length, "Invalid pool ID");
    require(_amount > 0, "Amount should be greater than 0");
    (observationIndex, observationCardinality) = PZENPZICPriceLib.updateObservation(
        pzenPzicPool,
        pzenTokenAddress,
        priceObservations,
        observationIndex,
        observationCardinality
    );
    
    // Update observation before processing deposit
    updateObservation();
    require(observations.length > 0, "No price data available");
    PoolInfo storage pool = poolInfo[_pid];
    UserInfo storage user = userInfo[_pid][msg.sender];

    uint256 pending = 0;
    if (user.amount > 0) {
        pending = _calcPendingReward(user, _pid);
    }

    // Check if there are enough reward tokens in the contract
    if (pending > 0 && !checkRewardTokenBalance(_pid, pending)) {
        emit InsufficientRewardTokens(_pid, pending, pool.rewardToken.balanceOf(address(this)));
        pending = 0; // Set pending to 0 to skip the reward transfer
    }

    // Calculate pzenEquivalent using the updated TWAP method
    uint256 pzenEquivalent = calculatePzenEquivalent(_amount);

    // Check user balance before updating state
    require(
        pool.depositToken.balanceOf(msg.sender) >= _amount,
        "Insufficient balance"
    );

    // Update user and pool information
    pool.depositedAmount += _amount;
    user.amount += _amount;
    user.pzenEquivalent += pzenEquivalent;
    user.lastRewardAt = block.timestamp;

    // Set lock period if not already active
    if (user.lockUntil <= block.timestamp) {
        user.lockUntil = block.timestamp + (pool.lockDays * 86400 * timeUnit / 86400);
    }

    // Create notification
    _createNotification(_pid, _amount, msg.sender, "Deposit");

    // Emit deposit event
    emit Deposit(msg.sender, _pid, _amount, pzenEquivalent);

    // Transfer deposit tokens from the user to the contract
    pool.depositToken.safeTransferFrom(msg.sender, address(this), _amount);

    // Handle pending rewards (at the end of the function)
    if (pending > 0) {
        require(
            pool.rewardToken.balanceOf(address(this)) >= pending,
            "Insufficient reward token balance"
        );
        pool.rewardToken.safeTransfer(msg.sender, pending);
        emit Claim(msg.sender, _pid, pending);
    }
}
// ... rest of the contract ...

    /**
     * @notice Constructor to set the PLP token address, PZEN token address, and initial time unit.
     * @param _plpTokenAddress The address of the PLP token contract.
     * @param _pzenTokenAddress The address of the PZEN token contract.
     * @param _initialTimeUnit The initial time unit in seconds (e.g., 86400 for 1 day, 60 for testing).
     */

    /**
     * @notice Allows the owner to set the time unit used for lock periods and reward calculations.
     * @param _timeUnit The new time unit in seconds. Must be at least 60 seconds.
     */
  function setTimeUnit(uint256 _timeUnit) external onlyOwner {
    uint256 oldTimeUnit = timeUnit;
    timeUnit = _timeUnit;
    emit TimeUnitUpdated(oldTimeUnit, _timeUnit);
}

    /**
     * @notice Allows the owner to set the PLP token address.
     * @param _plpTokenAddress The address of the PLP token contract.
     */
    function setPlpTokenAddress(address _plpTokenAddress) external onlyOwner {
        require(_plpTokenAddress != address(0), "Invalid PLP token address");
        plpTokenAddress = _plpTokenAddress;
        plpContract = IPulseLiquidityPool(_plpTokenAddress);
    }

    /**
     * @notice Allows the owner to set the PZEN token address.
     * @param _pzenTokenAddress The address of the PZEN token contract.
     */
    function setPzenTokenAddress(address _pzenTokenAddress) external onlyOwner {
        require(_pzenTokenAddress != address(0), "Invalid PZEN token address");
        pzenTokenAddress = _pzenTokenAddress;
    }
// Add this function to your contract
function _createNotification(uint256 _id, uint256 _amount, address _user, string memory _typeOf) internal {
    notifications.push(Notification({
        poolID: _id,
        amount: _amount,
        user: _user,
        typeOf: _typeOf,
        timestamp: block.timestamp
    }));
}

// Add this function to your contract
function getNotifications() public view returns (Notification[] memory) {
    return notifications;
}

    /**
     * @notice Allows the owner to add a new staking pool.
     * @param _depositToken The token that users will deposit (should be PLP).
     * @param _rewardToken The token that users will receive as rewards (PZIC).
     * @param _apy The annual percentage yield of the pool.
     * @param _lockDays The number of days the funds will be locked.
     */
    function addPool(
        IERC20 _depositToken,
        IERC20 _rewardToken,
        uint256 _apy,
        uint256 _lockDays
    ) public onlyOwner {
        require(address(_depositToken) == plpTokenAddress, "Deposit token must be PLP");
        poolInfo.push(
            PoolInfo({
                 poolID: poolCount,  // Use the current poolCount as the poolID
                 depositToken: _depositToken,
                rewardToken: _rewardToken,
                depositedAmount: 0,
                apy: _apy,
                lockDays: _lockDays
            })
        );

        poolCount++;
    }

    /**
     * @notice Calculates the PZEN equivalent of the deposited PLP amount using on-chain data.
     * @param _plpAmount The amount of PLP tokens deposited (18 decimals).
     * @return pzenEquivalent The calculated PZEN equivalent (9 decimals).
     */
   

    /**
     * @notice Allows users to deposit PLP tokens into the pool.
     * @param _pid The ID of the pool.
     * @param _amount The amount of PLP tokens to deposit (18 decimals).
     */
   

    /**
     * @notice Allows users to withdraw their deposited PLP tokens and claim rewards.
     * @param _pid The ID of the pool.
     * @param _amount The amount of PLP tokens to withdraw (18 decimals).
     */
       /**
     * @notice Checks if a user can withdraw a specific amount from a pool.
     * @param _pid The ID of the pool.
     * @param _amount The amount of PLP tokens to withdraw (18 decimals).
    
     * @param _user The address of the user.
     * @return canWithdrawResult A boolean indicating if the withdrawal is possible.
     * @return reason A string explaining why the withdrawal is not possible, if applicable.
     */
function canWithdraw(
    uint256 _pid,
    uint256 _amount,
    address _user
) public view returns (bool canWithdrawResult, string memory reason) {
    require(_pid < poolInfo.length, "Invalid pool ID");
    UserInfo storage user = userInfo[_pid][_user];

    if (user.amount < _amount) {
        return (false, "Withdraw amount exceeds balance");
    }

    if (user.lockUntil > block.timestamp) {
        return (false, "Lock period not ended");
    }

    return (true, "");
}


    // ... rest of the contract ...

 function withdraw(uint256 _pid, uint256 _amount) public nonReentrant {
    require(_pid < poolInfo.length, "Invalid pool ID");
    require(_amount > 0, "Amount should be greater than 0");
(observationIndex, observationCardinality) = PZENPZICPriceLib.updateObservation(
            pzenPzicPool,
            pzenTokenAddress,
            priceObservations,
            observationIndex,
            observationCardinality
        );
    // Update observation before processing withdrawal
    updateObservation();

    PoolInfo storage pool = poolInfo[_pid];
    UserInfo storage user = userInfo[_pid][msg.sender];

    require(user.amount >= _amount, "Withdraw amount exceeds balance");
    require(user.lockUntil <= block.timestamp, "Lock period not ended");

    // Calculate the proportion of pzenEquivalent to withdraw using the updated TWAP method
    uint256 totalPzenEquivalent = calculatePzenEquivalent(user.amount);
    uint256 pzenEquivalentToWithdraw = (totalPzenEquivalent * _amount) / user.amount;

    // Calculate pending rewards
    uint256 pending = _calcPendingReward(user, _pid);

    // New code: Check reward token balance and adjust pending if necessary
    uint256 rewardBalance = pool.rewardToken.balanceOf(address(this));
    if (rewardBalance < pending) {
        emit InsufficientRewardTokens(_pid, pending, rewardBalance);
        pending = rewardBalance;
    }

    // Update user information
    user.amount -= _amount;
    user.pzenEquivalent = totalPzenEquivalent - pzenEquivalentToWithdraw;
    pool.depositedAmount -= _amount;

    // Reset lock period if there are remaining tokens
    if (user.amount > 0) {
        user.lockUntil = block.timestamp + (pool.lockDays * 86400 * timeUnit /86400 );
    } else {
        user.lockUntil = 0;
    }

    user.lastRewardAt = block.timestamp;

    // Create notifications
    if (pending > 0) {
        _createNotification(_pid, pending, msg.sender, "Claim");
    }
    if (_amount > 0) {
        _createNotification(_pid, _amount, msg.sender, "Withdraw");
    }

    // Emit events
    emit Withdraw(msg.sender, _pid, _amount, pzenEquivalentToWithdraw);
    if (pending > 0) {
        emit Claim(msg.sender, _pid, pending);
    }

    // Transfer tokens after all state changes and events
    pool.depositToken.safeTransfer(msg.sender, _amount);

    if (pending > 0) {
        // This check is now redundant due to the earlier adjustment, but kept for extra safety
        require(
            pool.rewardToken.balanceOf(address(this)) >= pending,
            "Insufficient reward token balance"
        );
        pool.rewardToken.safeTransfer(msg.sender, pending);
    }

    // New code: Emit an event with detailed withdrawal information
    emit WithdrawDetails(_pid, _amount, pzenEquivalentToWithdraw, pending, rewardBalance);
}

// Add this event declaration at the top of your contract
event WithdrawDetails(uint256 indexed pid, uint256 amount, uint256 pzenEquivalentWithdrawn, uint256 pendingRewards, uint256 contractRewardBalance);

    /**
     * @notice Allows users to claim their rewards without withdrawing their staked tokens.
     * @param _pid The ID of the pool.
     */
function claimReward(uint256 _pid) public nonReentrant {
    require(_pid < poolInfo.length, "Invalid pool ID");
    PoolInfo storage pool = poolInfo[_pid];
    UserInfo storage user = userInfo[_pid][msg.sender];

    // Check if the user has deposited tokens
    require(user.amount > 0, "No tokens deposited in this pool");
    require(user.lockUntil <= block.timestamp, "Lock is active");

    // Update observation before processing claim
    updateObservation();

    uint256 pending = _calcPendingReward(user, _pid);
    require(pending > 0, "No rewards to claim");

    // Check if there are enough reward tokens in the contract
    if (!checkRewardTokenBalance(_pid, pending)) {
        emit InsufficientRewardTokens(_pid, pending, pool.rewardToken.balanceOf(address(this)));
        revert("Insufficient reward tokens in the contract");
    }

      // Only after successful transfer, update state and emit events
    user.lastRewardAt = block.timestamp;
    user.lockUntil = block.timestamp + (pool.lockDays * 86400 * timeUnit /86400);
    user.pzenEquivalent = calculatePzenEquivalent(user.amount);

     // Create notification
    _createNotification(_pid, pending, msg.sender, "Claim");

    // Emit event
    emit Claim(msg.sender, _pid, pending);
           // Transfer the pending rewards to the user
           require(
        pool.rewardToken.balanceOf(address(this)) >= pending,
        "Insufficient reward token balance"
    );
    pool.rewardToken.safeTransfer(msg.sender, pending);
}

    /**
     * @notice View function to see pending rewards for a user.
     * @param _pid The ID of the pool.
     * @param _user The address of the user.
     * @return The amount of pending rewards (18 decimals).
     */
    function pendingReward(uint256 _pid, address _user) public view returns (uint256) {
        UserInfo storage user = userInfo[_pid][_user]; // Get user information
        return _calcPendingReward(user, _pid);         // Calculate pending rewards
    }

    /**
     * @notice Internal function to calculate pending rewards for a user.
     * @param user The user information.
     * @param _pid The ID of the pool.
     * @return The amount of pending rewards (18 decimals).
     */
  function _calcPendingReward(UserInfo storage user, uint256 _pid)
    internal
    view
    returns (uint256)
{
    PoolInfo storage pool = poolInfo[_pid]; // Get pool information

    // Calculate the number of periods passed since the last reward calculation
    uint256 periodsPassed = (block.timestamp > user.lastRewardAt)
        ? (block.timestamp - user.lastRewardAt) / timeUnit
        : 0;

    // Ensure periodsPassed does not exceed the lockDays
    uint256 maxPeriods = pool.lockDays *86400 /timeUnit; // Since timeUnit is in days, lockDays corresponds to max periods
    if (periodsPassed > maxPeriods) {
        periodsPassed = maxPeriods;
    }

    // If no periods have passed or the user has no pzenEquivalent, return 0
    if (periodsPassed == 0 || user.pzenEquivalent == 0) {
        return (0);
    }
 
    // Calculate reward based on pzenEquivalent, APY, and time
    // Perform multiplication before division
    uint256 rewardNumerator = user.pzenEquivalent * pool.apy * periodsPassed;
    uint256 rewardDenominator = 365 * 100;
   

    // Get the current PZEN/PZIC price ratio
    uint256 pzenPzicRatio = PZENPZICPriceLib.calculateTWAP(
        pzenPzicPool,
        pzenTokenAddress,
        priceObservations,
        observationIndex,
        observationCardinality
    );

    // Convert reward from PZEN to PZIC using the TWAP ratio
    // Perform multiplication before division
    
    // Calculate pzicReward without intermediate division
    uint256 pzicReward = (rewardNumerator * pzenPzicRatio) / (rewardDenominator * 1e18);

    // Return the calculated reward in PZIC
    return pzicReward;
}


    
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @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);

    /**
     * @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 `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, 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 `from` to `to` 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 from, address to, uint256 amount) external returns (bool);
}

// 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
// OpenZeppelin Contracts (last updated v4.9.4) (token/ERC20/extensions/IERC20Permit.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 *
 * ==== Security Considerations
 *
 * There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
 * expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
 * considered as an intention to spend the allowance in any specific way. The second is that because permits have
 * built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
 * take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
 * generally recommended is:
 *
 * ```solidity
 * function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
 *     try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
 *     doThing(..., value);
 * }
 *
 * function doThing(..., uint256 value) public {
 *     token.safeTransferFrom(msg.sender, address(this), value);
 *     ...
 * }
 * ```
 *
 * Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
 * `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
 * {SafeERC20-safeTransferFrom}).
 *
 * Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
 * contracts should have entry points that don't rely on permit.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     *
     * CAUTION: See Security Considerations above.
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);

    /**
     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (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 Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby disabling 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
pragma solidity ^0.8.0;

import "@openzeppelin/contracts/utils/math/SafeMath.sol";

interface IPZENPZICPool {
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function token0() external view returns (address);
    function token1() external view returns (address);
}

library PZENPZICPriceLib {
    using SafeMath for uint256;

    struct Observation {
        uint timestamp;
        uint256 pzenReserve;
        uint256 pzicReserve;
    }

    uint256 private constant OBSERVATION_PERIOD = 1 hours;
    uint256 private constant MAX_OBSERVATIONS = 24; // Store up to 24 hours of hourly prices

    event TWAPCalculated(uint256 twap);
    // Rename this event
   event PZENPZICObservationUpdated(uint256 timestamp, uint256 pzenReserve, uint256 pzicReserve, uint32 blockTimestampLast);

    function calculateTWAP(
        IPZENPZICPool pool,
        address pzenAddress,
        Observation[MAX_OBSERVATIONS] storage observations,
        uint256 observationIndex,
        uint256 observationCardinality
    ) internal view returns (uint256) {
        require(observationCardinality > 0, "No observations");

        uint256 timeWeightedReserveRatio;
        uint256 timeSum;

        for (uint256 i = 0; i < observationCardinality - 1; i++) {
            uint256 nextIndex = (observationIndex + 1 + i) % observationCardinality;
            uint256 currentIndex = (observationIndex + i) % observationCardinality;

            Observation memory current = observations[currentIndex];
            Observation memory next = observations[nextIndex];

            uint256 timeInterval = next.timestamp - current.timestamp;
            // This calculates PZIC/PZEN ratio, which is correct for your use case
            //uint256 reserveRatio = current.pzicReserve.mul(1e18).div(current.pzenReserve);

            //timeWeightedReserveRatio = timeWeightedReserveRatio.add(reserveRatio.mul(timeInterval));
            uint256 numerator = current.pzicReserve.mul(1e18).mul(timeInterval);
timeWeightedReserveRatio = timeWeightedReserveRatio.add(numerator.div(current.pzenReserve));
            timeSum = timeSum.add(timeInterval);
        }

       if (timeSum == 0) {
    // If we don't have enough data for TWAP, use the current ratio
    (uint112 reserve0, uint112 reserve1,uint32 blockTimestampLast) = pool.getReserves();
     // blockTimestampLast is captured to match the interface, but not used in this implementation
    address token0 = pool.token0();
    
    uint256 pzenReserve = token0 == pzenAddress ? uint256(reserve0) : uint256(reserve1);
    uint256 pzicReserve = token0 == pzenAddress ? uint256(reserve1) : uint256(reserve0);
    uint256 currentRatio = pzicReserve.mul(1e18).div(pzenReserve);
            // Dummy calculation to use blockTimestampLast
        uint256 dummy = uint256(blockTimestampLast);
        dummy;  // Silences the "unused variable" warning
    return currentRatio;
}

        uint256 twap = timeWeightedReserveRatio.div(timeSum);
        
        return twap;
    }

    function updateObservation(
        IPZENPZICPool pool,
        address pzenAddress,
        Observation[MAX_OBSERVATIONS] storage observations,
        uint256 observationIndex,
        uint256 observationCardinality
    ) internal returns (uint256, uint256) {
        (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast) = pool.getReserves();
          // blockTimestampLast is captured to match the interface, but not used in this implementation
        address token0 = pool.token0();
        
        uint256 pzenReserve = token0 == pzenAddress ? uint256(reserve0) : uint256(reserve1);
        uint256 pzicReserve = token0 == pzenAddress ? uint256(reserve1) : uint256(reserve0);

        observations[observationIndex] = Observation(block.timestamp, pzenReserve, pzicReserve);

        // Update this line to use the new event name
        emit PZENPZICObservationUpdated(block.timestamp, pzenReserve, pzicReserve, blockTimestampLast);

        observationIndex = (observationIndex + 1) % MAX_OBSERVATIONS;
        if (observationCardinality < MAX_OBSERVATIONS) {
            observationCardinality++;
        }

        return (observationIndex, observationCardinality);
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (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() {
        _nonReentrantBefore();
        _;
        _nonReentrantAfter();
    }

    function _nonReentrantBefore() private {
        // On the first call to nonReentrant, _status will be _NOT_ENTERED
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
    }

    function _nonReentrantAfter() private {
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
     * `nonReentrant` function in the call stack.
     */
    function _reentrancyGuardEntered() internal view returns (bool) {
        return _status == _ENTERED;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.3) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

import "../IERC20.sol";
import "../extensions/IERC20Permit.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;

    /**
     * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    /**
     * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
     * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
     */
    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));
    }

    /**
     * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 oldAllowance = token.allowance(address(this), spender);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
    }

    /**
     * @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    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");
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
        }
    }

    /**
     * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
     * to be set to zero before setting it to a non-zero value, such as USDT.
     */
    function forceApprove(IERC20 token, address spender, uint256 value) internal {
        bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);

        if (!_callOptionalReturnBool(token, approvalCall)) {
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
            _callOptionalReturn(token, approvalCall);
        }
    }

    /**
     * @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
     * Revert on invalid signature.
     */
    function safePermit(
        IERC20Permit token,
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        uint256 nonceBefore = token.nonces(owner);
        token.permit(owner, spender, value, deadline, v, r, s);
        uint256 nonceAfter = token.nonces(owner);
        require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
    }

    /**
     * @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");
        require(returndata.length == 0 || abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
    }

    /**
     * @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).
     *
     * This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
     */
    function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
        // 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 cannot use {Address-functionCall} here since this should return false
        // and not revert is the subcall reverts.

        (bool success, bytes memory returndata) = address(token).call(data);
        return
            success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/math/SafeMath.sol)

pragma solidity ^0.8.0;

// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        return a + b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}

{
  "compilationTarget": {
    "contracts/SEP26/Eth4.sol": "Eth4"
  },
  "evmVersion": "cancun",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": false,
    "runs": 200
  },
  "remappings": []
}