// File: contracts/stakingV1/OTStakingV1.sol



// SPDX-License-Identifier: MIT

/*
Staking contract of the Otter protocol.

Telegram: https://t.me/otterprotocol
Website: https://otterprotocol.com/
X/Twitter: https://twitter.com/OtterProtocol 
Docs: https://otter-protocol.gitbook.io/otter-protocol/

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*/

pragma solidity =0.8.15;
import "@openzeppelin/contracts/utils/Context.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "./SafeMath.sol";

contract OTStakingV1 is Ownable, ReentrancyGuard {
    struct StakingDetails {
        uint256 amount;
        uint256 deposit_time;
        uint256 unlock_time;
        uint256 last_claim_time;
        bool participant;
    }

    using SafeMath for uint256;

    address public LP_token_address;
    IERC20 public LP_token;

    uint256 public locking_period;

    bool public claim_enabled = false;

    uint256 public total_lp_tokens;
    uint256 public depositors;
    uint256 public eth_per_block = 10000000000000;
    uint256 public earlyExitTax = 33;

    uint256 minThreshold = 1000000000000000000;

    event RewardsAdded(uint256 deposit_amount, uint256 time);
    event RunningLowOnRewards(uint256 left_remaining, uint256 time);
    event Claimed(address account, uint256 amount_due, uint256 time);
    event LargeDeposit(address account, uint256 amount, uint256 time);

    mapping(address => StakingDetails) public stake_details;

    constructor() {
        LP_token_address = 0x181Eb1DB23ea646F286A1638FB44A634e0B62Acb;
        LP_token = IERC20(LP_token_address);
        locking_period = 604800; // one week
    }

    receive() external payable {}

    function ReturnLPbalance() public view returns (uint256) {
        return LP_token.balanceOf(address(this));
    }

    function ReturnETHbalance() public view returns (uint256) {
        return address(this).balance;
    }

    function FetchEthPerBlock() internal view returns (uint256) {
        return eth_per_block;
    }

    function DepositRewards() public payable onlyOwner {
        emit RewardsAdded(msg.value, block.timestamp);
    }

    function EnableClaim(bool state) public onlyOwner {
        claim_enabled = state;
    }

    function ChangeEthPerBlock(uint256 newvalue) public onlyOwner {
        eth_per_block = newvalue;
    }

    function ChangeEarlyExitTax(uint256 newvalue) public onlyOwner {
        earlyExitTax = newvalue;
    }

    function ChangeLockingPeriod(uint256 newtime) public onlyOwner {
        require(newtime <= 1209600, "Can't set lock longer then 2 weeks.");
        locking_period = newtime;
    }

    // have to approve the vault on the pair contract first
    function Deposit_LP(uint256 amount) public nonReentrant {
        require(amount > 0);
        amount = amount * 10**18;
        if (stake_details[msg.sender].participant == true) {
            if (claim_enabled) {
                internalClaim(msg.sender);
            }
            stake_details[msg.sender].amount += amount;
            LP_token.transferFrom(msg.sender, address(this), amount);
            total_lp_tokens += amount;
        } else {
            bool success = LP_token.transferFrom(
                msg.sender,
                address(this),
                amount
            );
            require(success);
            depositors += 1;

            stake_details[msg.sender].amount += amount;

            stake_details[msg.sender].participant = true;

            stake_details[msg.sender].deposit_time = block.timestamp;

            stake_details[msg.sender].last_claim_time = block.timestamp;

            stake_details[msg.sender].unlock_time =
                block.timestamp +
                locking_period;

            total_lp_tokens += amount;
        }
    }

    function WithdrawLP() public nonReentrant {
        require(stake_details[msg.sender].participant == true);
        // If lock period didn't end, exit early with an early exit fee
        if (
            stake_details[msg.sender].deposit_time + locking_period >
            block.timestamp
        ) {
            uint256 fee = stake_details[msg.sender]
                .amount
                .mul(earlyExitTax)
                .div(100); //
            uint256 amount = stake_details[msg.sender].amount;
            stake_details[msg.sender].amount = amount.sub(fee);
            LP_token.transfer(owner(), fee); // Transfer fee to the owner
        }

        if (stake_details[msg.sender].last_claim_time < block.timestamp) {
            if (claim_enabled) {
                internalClaim(msg.sender);
            }
        }

        stake_details[msg.sender].participant = false;
        depositors -= 1;
        bool success = LP_token.transfer(
            msg.sender,
            stake_details[msg.sender].amount
        );
        require(success);
        total_lp_tokens -= stake_details[msg.sender].amount;
        stake_details[msg.sender].amount = 0;
    }

    function internalClaim(address account) private {
        require(claim_enabled, "Claim has not been enabled yet.");
        require(
            stake_details[account].participant == true,
            "Not recognized as acive staker."
        );
        require(
            block.timestamp > stake_details[account].last_claim_time,
            "You can only claim once per block."
        );

        stake_details[account].last_claim_time = block.timestamp;

        uint256 amount_due = getPendingReturns(account);

        if (amount_due == 0) {
            return;
        }

        (bool success, ) = payable(account).call{value: amount_due}("");
        require(success);

        emit Claimed(account, amount_due, block.timestamp);

        if (address(this).balance <= minThreshold) {
            emit RunningLowOnRewards(address(this).balance, block.timestamp);
        }
    }

    function Claim() public nonReentrant {
        require(claim_enabled, "Claim has not been enabled yet.");
        require(
            stake_details[msg.sender].participant == true,
            "Not recognized as active staker."
        );
        require(
            block.timestamp > stake_details[msg.sender].last_claim_time,
            "You can only claim once per block."
        );
        require(
            block.timestamp <=
                stake_details[msg.sender].deposit_time + locking_period,
            "You must re-lock your LP for another lock duration before claiming again. Withdraw will auto claim rewards."
        );

        uint256 amount_due = getPendingReturns(msg.sender);

        stake_details[msg.sender].last_claim_time = block.timestamp;

        if (amount_due == 0) {
            return;
        }

        (bool success, ) = payable(msg.sender).call{value: amount_due}("");
        require(success);

        emit Claimed(msg.sender, amount_due, block.timestamp);

        if (address(this).balance <= minThreshold) {
            emit RunningLowOnRewards(address(this).balance, block.timestamp);
        }
    }

    function Compound() public nonReentrant {
        require(
            stake_details[msg.sender].participant == true,
            "Not recognized as active staker."
        );
        require(
            stake_details[msg.sender].deposit_time + locking_period <=
                block.timestamp,
            "You're still locked. Wait for lock duration to time out."
        );

        if (stake_details[msg.sender].last_claim_time < block.timestamp) {
            internalClaim(msg.sender);
        }

        stake_details[msg.sender].deposit_time = block.timestamp;

        stake_details[msg.sender].last_claim_time = block.timestamp;
        stake_details[msg.sender].unlock_time =
            block.timestamp +
            locking_period;
    }

    function getTimeInPool(address account) public view returns (uint256) {
        return stake_details[account].deposit_time - block.timestamp;
    }

    function getTimeleftTillUnlock(address account)
        public
        view
        returns (uint256)
    {
        return
            stake_details[account].deposit_time +
            locking_period -
            block.timestamp;
    }

    function getPendingReturns(address account) public view returns (uint256) {
        uint256 reward_blocks = block.timestamp -
            stake_details[account].last_claim_time;
        uint256 reward_rate = FetchEthPerBlock();
        uint256 amount_due = ((reward_rate * users_pool_percentage(account)) /
            10000) * reward_blocks;
        return amount_due;
    }

    function users_pool_percentage(address account)
        public
        view
        returns (uint256)
    {
        uint256 userStake = stake_details[account].amount;
        uint256 totalSupply = LP_token.balanceOf(address(this));

        if (totalSupply == 0) {
            return 0; // Avoid division by zero
        }

        uint256 percentage = (userStake * 10000) / totalSupply;

        return percentage;
    }

    function rescueETH20Tokens(address tokenAddress) external onlyOwner {
        IERC20(tokenAddress).transfer(
            owner(),
            IERC20(tokenAddress).balanceOf(address(this))
        );
    }

    function ForceSend() external onlyOwner {
        uint256 ETHbalance = address(this).balance;
        (bool success, ) = payable(owner()).call{value: ETHbalance}("");
        require(success);
    }
}

// File: contracts/stakingV1/SafeMath.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.6;

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

        return c;
    }

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

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

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

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

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

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

/**
 * @title SafeMathInt
 * @dev Math operations for int256 with overflow safety checks.
 */
library SafeMathInt {
    int256 private constant MIN_INT256 = int256(1) << 255;
    int256 private constant MAX_INT256 = ~(int256(1) << 255);

    /**
     * @dev Multiplies two int256 variables and fails on overflow.
     */
    function mul(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a * b;

        // Detect overflow when multiplying MIN_INT256 with -1
        require(c != MIN_INT256 || (a & MIN_INT256) != (b & MIN_INT256));
        require((b == 0) || (c / b == a));
        return c;
    }

    /**
     * @dev Division of two int256 variables and fails on overflow.
     */
    function div(int256 a, int256 b) internal pure returns (int256) {
        // Prevent overflow when dividing MIN_INT256 by -1
        require(b != -1 || a != MIN_INT256);

        // Solidity already throws when dividing by 0.
        return a / b;
    }

    /**
     * @dev Subtracts two int256 variables and fails on overflow.
     */
    function sub(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a - b;
        require((b >= 0 && c <= a) || (b < 0 && c > a));
        return c;
    }

    /**
     * @dev Adds two int256 variables and fails on overflow.
     */
    function add(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a + b;
        require((b >= 0 && c >= a) || (b < 0 && c < a));
        return c;
    }

    /**
     * @dev Converts to absolute value, and fails on overflow.
     */
    function abs(int256 a) internal pure returns (int256) {
        require(a != MIN_INT256);
        return a < 0 ? -a : a;
    }


    function toUint256Safe(int256 a) internal pure returns (uint256) {
        require(a >= 0);
        return uint256(a);
    }
}

/**
 * @title SafeMathUint
 * @dev Math operations with safety checks that revert on error
 */
library SafeMathUint {
  function toInt256Safe(uint256 a) internal pure returns (int256) {
    int256 b = int256(a);
    require(b >= 0);
    return b;
  }
}
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// 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);
}

// File: @openzeppelin/contracts/security/ReentrancyGuard.sol



// 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;
    }
}

// File: @openzeppelin/contracts/access/Ownable.sol



// 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);
    }
}

// File: @openzeppelin/contracts/utils/Context.sol



// 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;
    }
}