// SPDX-License-Identifier: No License
pragma solidity ^0.8.0;

import "layerzerolabs/contracts/token/oft/OFT.sol";
import "layerzerolabs/contracts/interfaces/IStargateRouter.sol";
import "communal/Owned.sol";
import "communal/TransferHelper.sol";

interface ISGETH is IERC20{
    function deposit() payable external;
}

contract ARBUnshethMinter is Owned {

    address public immutable stargateRouterAddress;          // address of the stargate router
    address public immutable sgethAddress;             // address of the sgeth token - 0x82cbecf39bee528b5476fe6d1550af59a9db6fc0
    uint16 public immutable dstChainId;                      // Stargate/LayerZero chainId
    uint16 public immutable srcPoolId;                       // stargate poolId - *must* be the poolId for the qty asset
    uint16 public immutable dstPoolId;                       // stargate destination poolId
    address public sgReceiverAddress;                         // destination contract. it must implement sgReceive()
    bool paused = false;

    constructor(
        address _owner, //address of the user deploying this contract
        address _stargateRouterAddress, //address of the stargate router on Arbitrum - 0x53Bf833A5d6c4ddA888F69c22C88C9f356a41614 as per https://stargateprotocol.gitbook.io/stargate/developers/contract-addresses/mainnet
        address _sgReceiver, //address of the sgReceiver deployed on ETH
        uint16 _dstChainId, //101 - as per https://stargateprotocol.gitbook.io/stargate/developers/contract-addresses/mainnet'
        uint16 _srcPoolId, // 13 - as per https://stargateprotocol.gitbook.io/stargate/developers/contract-addresses/mainnet
        uint16 _dstPoolId, // 13 - as per https://stargateprotocol.gitbook.io/stargate/developers/contract-addresses/mainnet,
        address _sgethAddress // 0x82cbecf39bee528b5476fe6d1550af59a9db6fc0
    ) Owned(_owner){
        stargateRouterAddress = _stargateRouterAddress;
        sgReceiverAddress = _sgReceiver;
        dstChainId = _dstChainId;
        srcPoolId = _srcPoolId;
        dstPoolId = _dstPoolId;
        sgethAddress = _sgethAddress;

        TransferHelper.safeApprove(sgethAddress, stargateRouterAddress, type(uint256).max);
    }

    modifier onlyWhenUnpaused {
        require(paused == false, "Contract is paused");
        _;
    }

    // owner function that sets the pause parameter
    function setPaused(bool _paused) public onlyOwner {
        paused = _paused;
    }

    function changeSgReceiver(address _sgReceiver) public onlyOwner {
        require(_sgReceiver!= address(0), "sgReceiver cannot be zero address");
        sgReceiverAddress = _sgReceiver;
    }

    // mint_unsheth function that sends ETH to the sgReceiver on Mainnet contract to mint unshETH tokens
    function mint_unsheth(
        uint256 amount,                         // the amount of ETH
        uint256 min_amount_stargate,            // the minimum amount of ETH to receive on stargate,
        uint256 min_amount_unshethZap,          // the minimum amount of unshETH to receive from the unshETH Zap
        uint256 dstGasForCall,                  // the amount of gas to send to the sgReceive contract
        uint256 dstNativeAmount,                // leftover eth that will get airdropped to the sgReceive contract
        uint256 unsheth_path                    // the path that the unsheth Zap will take to mint unshETH
    ) external payable onlyWhenUnpaused {
        // ensure the msg.value is greather than the amount of ETH being sent
        require(msg.value > amount, "Not enough ETH provided as msg.value");

        // deposit the ETH into the sgeth contract
        ISGETH(sgethAddress).deposit{value:amount}();

        //calculate the fee that will be used to pay for the swap 
        uint256 feeAmount = msg.value - amount;

        bytes memory data = abi.encode(msg.sender, min_amount_unshethZap, unsheth_path);

        // Encode payload data to send to destination contract, which it will handle with sgReceive()
        IStargateRouter(stargateRouterAddress).swap{value:feeAmount}( //call estimateGasFees to get the msg.value
            dstChainId,                                               // the destination chain id - ETH
            srcPoolId,                                                // the source Stargate poolId
            dstPoolId,                                                // the destination Stargate poolId
            payable(msg.sender),                                      // refund address. if msg.sender pays too much gas, return extra ETH to this address
            amount,                                                   // total tokens to send to destination chain
            min_amount_stargate,                                      // min amount allowed out
            IStargateRouter.lzTxObj(dstGasForCall, dstNativeAmount, abi.encodePacked(sgReceiverAddress)), // default lzTxObj
            abi.encodePacked(sgReceiverAddress),                   // destination address, the sgReceive() implementer
            data                                                      // bytes payload which sgReceive() will parse into an address that the unshETH will be sent too.
        );
    }
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.11;

import "../Utils/EnumerableSet.sol";
import "../Utils/Address.sol";
import "../Common/Context.sol";

/**
 * @dev Contract module that allows children to implement role-based access
 * control mechanisms.
 *
 * Roles are referred to by their `bytes32` identifier. These should be exposed
 * in the external API and be unique. The best way to achieve this is by
 * using `public constant` hash digests:
 *
 * ```
 * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
 * ```
 *
 * Roles can be used to represent a set of permissions. To restrict access to a
 * function call, use {hasRole}:
 *
 * ```
 * function foo() public {
 *     require(hasRole(MY_ROLE, msg.sender));
 *     ...
 * }
 * ```
 *
 * Roles can be granted and revoked dynamically via the {grantRole} and
 * {revokeRole} functions. Each role has an associated admin role, and only
 * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
 *
 * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
 * that only accounts with this role will be able to grant or revoke other
 * roles. More complex role relationships can be created by using
 * {_setRoleAdmin}.
 *
 * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
 * grant and revoke this role. Extra precautions should be taken to secure
 * accounts that have been granted it.
 */
abstract contract AccessControl is Context {
    using EnumerableSet for EnumerableSet.AddressSet;
    using Address for address;

    struct RoleData {
        EnumerableSet.AddressSet members;
        bytes32 adminRole;
    }

    mapping (bytes32 => RoleData) private _roles;

    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00; //bytes32(uint256(0x4B437D01b575618140442A4975db38850e3f8f5f) << 96);

    /**
     * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
     *
     * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
     * {RoleAdminChanged} not being emitted signaling this.
     *
     * _Available since v3.1._
     */
    event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);

    /**
     * @dev Emitted when `account` is granted `role`.
     *
     * `sender` is the account that originated the contract call, an admin role
     * bearer except when using {_setupRole}.
     */
    event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Emitted when `account` is revoked `role`.
     *
     * `sender` is the account that originated the contract call:
     *   - if using `revokeRole`, it is the admin role bearer
     *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
     */
    event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Returns `true` if `account` has been granted `role`.
     */
    function hasRole(bytes32 role, address account) public view returns (bool) {
        return _roles[role].members.contains(account);
    }

    /**
     * @dev Returns the number of accounts that have `role`. Can be used
     * together with {getRoleMember} to enumerate all bearers of a role.
     */
    function getRoleMemberCount(bytes32 role) public view returns (uint256) {
        return _roles[role].members.length();
    }

    /**
     * @dev Returns one of the accounts that have `role`. `index` must be a
     * value between 0 and {getRoleMemberCount}, non-inclusive.
     *
     * Role bearers are not sorted in any particular way, and their ordering may
     * change at any point.
     *
     * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
     * you perform all queries on the same block. See the following
     * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]
     * for more information.
     */
    function getRoleMember(bytes32 role, uint256 index) public view returns (address) {
        return _roles[role].members.at(index);
    }

    /**
     * @dev Returns the admin role that controls `role`. See {grantRole} and
     * {revokeRole}.
     *
     * To change a role's admin, use {_setRoleAdmin}.
     */
    function getRoleAdmin(bytes32 role) public view returns (bytes32) {
        return _roles[role].adminRole;
    }

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function grantRole(bytes32 role, address account) public virtual {
        require(hasRole(_roles[role].adminRole, _msgSender()), "AccessControl: sender must be an admin to grant");

        _grantRole(role, account);
    }

    /**
     * @dev Revokes `role` from `account`.
     *
     * If `account` had been granted `role`, emits a {RoleRevoked} event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function revokeRole(bytes32 role, address account) public virtual {
        require(hasRole(_roles[role].adminRole, _msgSender()), "AccessControl: sender must be an admin to revoke");

        _revokeRole(role, account);
    }

    /**
     * @dev Revokes `role` from the calling account.
     *
     * Roles are often managed via {grantRole} and {revokeRole}: this function's
     * purpose is to provide a mechanism for accounts to lose their privileges
     * if they are compromised (such as when a trusted device is misplaced).
     *
     * If the calling account had been granted `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `account`.
     */
    function renounceRole(bytes32 role, address account) public virtual {
        require(account == _msgSender(), "AccessControl: can only renounce roles for self");

        _revokeRole(role, account);
    }

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event. Note that unlike {grantRole}, this function doesn't perform any
     * checks on the calling account.
     *
     * [WARNING]
     * ====
     * This function should only be called from the constructor when setting
     * up the initial roles for the system.
     *
     * Using this function in any other way is effectively circumventing the admin
     * system imposed by {AccessControl}.
     * ====
     */
    function _setupRole(bytes32 role, address account) internal virtual {
        _grantRole(role, account);
    }

    /**
     * @dev Sets `adminRole` as ``role``'s admin role.
     *
     * Emits a {RoleAdminChanged} event.
     */
    function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
        emit RoleAdminChanged(role, _roles[role].adminRole, adminRole);
        _roles[role].adminRole = adminRole;
    }

    function _grantRole(bytes32 role, address account) private {
        if (_roles[role].members.add(account)) {
            emit RoleGranted(role, account, _msgSender());
        }
    }

    function _revokeRole(bytes32 role, address account) private {
        if (_roles[role].members.remove(account)) {
            emit RoleRevoked(role, account, _msgSender());
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (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
     * ====
     *
     * [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://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                /// @solidity memory-safe-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// SPDX-License-Identifier: Unlicense
/*
 * @title Solidity Bytes Arrays Utils
 * @author Gonçalo Sá <goncalo.sa@consensys.net>
 *
 * @dev Bytes tightly packed arrays utility library for ethereum contracts written in Solidity.
 *      The library lets you concatenate, slice and type cast bytes arrays both in memory and storage.
 */
pragma solidity >=0.8.0 <0.9.0;


library BytesLib {
    function concat(
        bytes memory _preBytes,
        bytes memory _postBytes
    )
    internal
    pure
    returns (bytes memory)
    {
        bytes memory tempBytes;

        assembly {
        // Get a location of some free memory and store it in tempBytes as
        // Solidity does for memory variables.
            tempBytes := mload(0x40)

        // Store the length of the first bytes array at the beginning of
        // the memory for tempBytes.
            let length := mload(_preBytes)
            mstore(tempBytes, length)

        // Maintain a memory counter for the current write location in the
        // temp bytes array by adding the 32 bytes for the array length to
        // the starting location.
            let mc := add(tempBytes, 0x20)
        // Stop copying when the memory counter reaches the length of the
        // first bytes array.
            let end := add(mc, length)

            for {
            // Initialize a copy counter to the start of the _preBytes data,
            // 32 bytes into its memory.
                let cc := add(_preBytes, 0x20)
            } lt(mc, end) {
            // Increase both counters by 32 bytes each iteration.
                mc := add(mc, 0x20)
                cc := add(cc, 0x20)
            } {
            // Write the _preBytes data into the tempBytes memory 32 bytes
            // at a time.
                mstore(mc, mload(cc))
            }

        // Add the length of _postBytes to the current length of tempBytes
        // and store it as the new length in the first 32 bytes of the
        // tempBytes memory.
            length := mload(_postBytes)
            mstore(tempBytes, add(length, mload(tempBytes)))

        // Move the memory counter back from a multiple of 0x20 to the
        // actual end of the _preBytes data.
            mc := end
        // Stop copying when the memory counter reaches the new combined
        // length of the arrays.
            end := add(mc, length)

            for {
                let cc := add(_postBytes, 0x20)
            } lt(mc, end) {
                mc := add(mc, 0x20)
                cc := add(cc, 0x20)
            } {
                mstore(mc, mload(cc))
            }

        // Update the free-memory pointer by padding our last write location
        // to 32 bytes: add 31 bytes to the end of tempBytes to move to the
        // next 32 byte block, then round down to the nearest multiple of
        // 32. If the sum of the length of the two arrays is zero then add
        // one before rounding down to leave a blank 32 bytes (the length block with 0).
            mstore(0x40, and(
            add(add(end, iszero(add(length, mload(_preBytes)))), 31),
            not(31) // Round down to the nearest 32 bytes.
            ))
        }

        return tempBytes;
    }

    function concatStorage(bytes storage _preBytes, bytes memory _postBytes) internal {
        assembly {
        // Read the first 32 bytes of _preBytes storage, which is the length
        // of the array. (We don't need to use the offset into the slot
        // because arrays use the entire slot.)
            let fslot := sload(_preBytes.slot)
        // Arrays of 31 bytes or less have an even value in their slot,
        // while longer arrays have an odd value. The actual length is
        // the slot divided by two for odd values, and the lowest order
        // byte divided by two for even values.
        // If the slot is even, bitwise and the slot with 255 and divide by
        // two to get the length. If the slot is odd, bitwise and the slot
        // with -1 and divide by two.
            let slength := div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
            let mlength := mload(_postBytes)
            let newlength := add(slength, mlength)
        // slength can contain both the length and contents of the array
        // if length < 32 bytes so let's prepare for that
        // v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storage
            switch add(lt(slength, 32), lt(newlength, 32))
            case 2 {
            // Since the new array still fits in the slot, we just need to
            // update the contents of the slot.
            // uint256(bytes_storage) = uint256(bytes_storage) + uint256(bytes_memory) + new_length
                sstore(
                _preBytes.slot,
                // all the modifications to the slot are inside this
                // next block
                add(
                // we can just add to the slot contents because the
                // bytes we want to change are the LSBs
                fslot,
                add(
                mul(
                div(
                // load the bytes from memory
                mload(add(_postBytes, 0x20)),
                // zero all bytes to the right
                exp(0x100, sub(32, mlength))
                ),
                // and now shift left the number of bytes to
                // leave space for the length in the slot
                exp(0x100, sub(32, newlength))
                ),
                // increase length by the double of the memory
                // bytes length
                mul(mlength, 2)
                )
                )
                )
            }
            case 1 {
            // The stored value fits in the slot, but the combined value
            // will exceed it.
            // get the keccak hash to get the contents of the array
                mstore(0x0, _preBytes.slot)
                let sc := add(keccak256(0x0, 0x20), div(slength, 32))

            // save new length
                sstore(_preBytes.slot, add(mul(newlength, 2), 1))

            // The contents of the _postBytes array start 32 bytes into
            // the structure. Our first read should obtain the `submod`
            // bytes that can fit into the unused space in the last word
            // of the stored array. To get this, we read 32 bytes starting
            // from `submod`, so the data we read overlaps with the array
            // contents by `submod` bytes. Masking the lowest-order
            // `submod` bytes allows us to add that value directly to the
            // stored value.

                let submod := sub(32, slength)
                let mc := add(_postBytes, submod)
                let end := add(_postBytes, mlength)
                let mask := sub(exp(0x100, submod), 1)

                sstore(
                sc,
                add(
                and(
                fslot,
                0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff00
                ),
                and(mload(mc), mask)
                )
                )

                for {
                    mc := add(mc, 0x20)
                    sc := add(sc, 1)
                } lt(mc, end) {
                    sc := add(sc, 1)
                    mc := add(mc, 0x20)
                } {
                    sstore(sc, mload(mc))
                }

                mask := exp(0x100, sub(mc, end))

                sstore(sc, mul(div(mload(mc), mask), mask))
            }
            default {
            // get the keccak hash to get the contents of the array
                mstore(0x0, _preBytes.slot)
            // Start copying to the last used word of the stored array.
                let sc := add(keccak256(0x0, 0x20), div(slength, 32))

            // save new length
                sstore(_preBytes.slot, add(mul(newlength, 2), 1))

            // Copy over the first `submod` bytes of the new data as in
            // case 1 above.
                let slengthmod := mod(slength, 32)
                let mlengthmod := mod(mlength, 32)
                let submod := sub(32, slengthmod)
                let mc := add(_postBytes, submod)
                let end := add(_postBytes, mlength)
                let mask := sub(exp(0x100, submod), 1)

                sstore(sc, add(sload(sc), and(mload(mc), mask)))

                for {
                    sc := add(sc, 1)
                    mc := add(mc, 0x20)
                } lt(mc, end) {
                    sc := add(sc, 1)
                    mc := add(mc, 0x20)
                } {
                    sstore(sc, mload(mc))
                }

                mask := exp(0x100, sub(mc, end))

                sstore(sc, mul(div(mload(mc), mask), mask))
            }
        }
    }

    function slice(
        bytes memory _bytes,
        uint256 _start,
        uint256 _length
    )
    internal
    pure
    returns (bytes memory)
    {
        require(_length + 31 >= _length, "slice_overflow");
        require(_bytes.length >= _start + _length, "slice_outOfBounds");

        bytes memory tempBytes;

        assembly {
            switch iszero(_length)
            case 0 {
            // Get a location of some free memory and store it in tempBytes as
            // Solidity does for memory variables.
                tempBytes := mload(0x40)

            // The first word of the slice result is potentially a partial
            // word read from the original array. To read it, we calculate
            // the length of that partial word and start copying that many
            // bytes into the array. The first word we copy will start with
            // data we don't care about, but the last `lengthmod` bytes will
            // land at the beginning of the contents of the new array. When
            // we're done copying, we overwrite the full first word with
            // the actual length of the slice.
                let lengthmod := and(_length, 31)

            // The multiplication in the next line is necessary
            // because when slicing multiples of 32 bytes (lengthmod == 0)
            // the following copy loop was copying the origin's length
            // and then ending prematurely not copying everything it should.
                let mc := add(add(tempBytes, lengthmod), mul(0x20, iszero(lengthmod)))
                let end := add(mc, _length)

                for {
                // The multiplication in the next line has the same exact purpose
                // as the one above.
                    let cc := add(add(add(_bytes, lengthmod), mul(0x20, iszero(lengthmod))), _start)
                } lt(mc, end) {
                    mc := add(mc, 0x20)
                    cc := add(cc, 0x20)
                } {
                    mstore(mc, mload(cc))
                }

                mstore(tempBytes, _length)

            //update free-memory pointer
            //allocating the array padded to 32 bytes like the compiler does now
                mstore(0x40, and(add(mc, 31), not(31)))
            }
            //if we want a zero-length slice let's just return a zero-length array
            default {
                tempBytes := mload(0x40)
            //zero out the 32 bytes slice we are about to return
            //we need to do it because Solidity does not garbage collect
                mstore(tempBytes, 0)

                mstore(0x40, add(tempBytes, 0x20))
            }
        }

        return tempBytes;
    }

    function toAddress(bytes memory _bytes, uint256 _start) internal pure returns (address) {
        require(_bytes.length >= _start + 20, "toAddress_outOfBounds");
        address tempAddress;

        assembly {
            tempAddress := div(mload(add(add(_bytes, 0x20), _start)), 0x1000000000000000000000000)
        }

        return tempAddress;
    }

    function toUint8(bytes memory _bytes, uint256 _start) internal pure returns (uint8) {
        require(_bytes.length >= _start + 1 , "toUint8_outOfBounds");
        uint8 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x1), _start))
        }

        return tempUint;
    }

    function toUint16(bytes memory _bytes, uint256 _start) internal pure returns (uint16) {
        require(_bytes.length >= _start + 2, "toUint16_outOfBounds");
        uint16 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x2), _start))
        }

        return tempUint;
    }

    function toUint32(bytes memory _bytes, uint256 _start) internal pure returns (uint32) {
        require(_bytes.length >= _start + 4, "toUint32_outOfBounds");
        uint32 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x4), _start))
        }

        return tempUint;
    }

    function toUint64(bytes memory _bytes, uint256 _start) internal pure returns (uint64) {
        require(_bytes.length >= _start + 8, "toUint64_outOfBounds");
        uint64 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x8), _start))
        }

        return tempUint;
    }

    function toUint96(bytes memory _bytes, uint256 _start) internal pure returns (uint96) {
        require(_bytes.length >= _start + 12, "toUint96_outOfBounds");
        uint96 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0xc), _start))
        }

        return tempUint;
    }

    function toUint128(bytes memory _bytes, uint256 _start) internal pure returns (uint128) {
        require(_bytes.length >= _start + 16, "toUint128_outOfBounds");
        uint128 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x10), _start))
        }

        return tempUint;
    }

    function toUint256(bytes memory _bytes, uint256 _start) internal pure returns (uint256) {
        require(_bytes.length >= _start + 32, "toUint256_outOfBounds");
        uint256 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x20), _start))
        }

        return tempUint;
    }

    function toBytes32(bytes memory _bytes, uint256 _start) internal pure returns (bytes32) {
        require(_bytes.length >= _start + 32, "toBytes32_outOfBounds");
        bytes32 tempBytes32;

        assembly {
            tempBytes32 := mload(add(add(_bytes, 0x20), _start))
        }

        return tempBytes32;
    }

    function equal(bytes memory _preBytes, bytes memory _postBytes) internal pure returns (bool) {
        bool success = true;

        assembly {
            let length := mload(_preBytes)

        // if lengths don't match the arrays are not equal
            switch eq(length, mload(_postBytes))
            case 1 {
            // cb is a circuit breaker in the for loop since there's
            //  no said feature for inline assembly loops
            // cb = 1 - don't breaker
            // cb = 0 - break
                let cb := 1

                let mc := add(_preBytes, 0x20)
                let end := add(mc, length)

                for {
                    let cc := add(_postBytes, 0x20)
                // the next line is the loop condition:
                // while(uint256(mc < end) + cb == 2)
                } eq(add(lt(mc, end), cb), 2) {
                    mc := add(mc, 0x20)
                    cc := add(cc, 0x20)
                } {
                // if any of these checks fails then arrays are not equal
                    if iszero(eq(mload(mc), mload(cc))) {
                    // unsuccess:
                        success := 0
                        cb := 0
                    }
                }
            }
            default {
            // unsuccess:
                success := 0
            }
        }

        return success;
    }

    function equalStorage(
        bytes storage _preBytes,
        bytes memory _postBytes
    )
    internal
    view
    returns (bool)
    {
        bool success = true;

        assembly {
        // we know _preBytes_offset is 0
            let fslot := sload(_preBytes.slot)
        // Decode the length of the stored array like in concatStorage().
            let slength := div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
            let mlength := mload(_postBytes)

        // if lengths don't match the arrays are not equal
            switch eq(slength, mlength)
            case 1 {
            // slength can contain both the length and contents of the array
            // if length < 32 bytes so let's prepare for that
            // v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storage
                if iszero(iszero(slength)) {
                    switch lt(slength, 32)
                    case 1 {
                    // blank the last byte which is the length
                        fslot := mul(div(fslot, 0x100), 0x100)

                        if iszero(eq(fslot, mload(add(_postBytes, 0x20)))) {
                        // unsuccess:
                            success := 0
                        }
                    }
                    default {
                    // cb is a circuit breaker in the for loop since there's
                    //  no said feature for inline assembly loops
                    // cb = 1 - don't breaker
                    // cb = 0 - break
                        let cb := 1

                    // get the keccak hash to get the contents of the array
                        mstore(0x0, _preBytes.slot)
                        let sc := keccak256(0x0, 0x20)

                        let mc := add(_postBytes, 0x20)
                        let end := add(mc, mlength)

                    // the next line is the loop condition:
                    // while(uint256(mc < end) + cb == 2)
                        for {} eq(add(lt(mc, end), cb), 2) {
                            sc := add(sc, 1)
                            mc := add(mc, 0x20)
                        } {
                            if iszero(eq(sload(sc), mload(mc))) {
                            // unsuccess:
                                success := 0
                                cb := 0
                            }
                        }
                    }
                }
            }
            default {
            // unsuccess:
                success := 0
            }
        }

        return success;
    }
}

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.6.11;
pragma experimental ABIEncoderV2;

// ====================================================================
// |     ______                   _______                             |
// |    / _____________ __  __   / ____(_____  ____ _____  ________   |
// |   / /_  / ___/ __ `| |/_/  / /_  / / __ \/ __ `/ __ \/ ___/ _ \  |
// |  / __/ / /  / /_/ _>  <   / __/ / / / / / /_/ / / / / /__/  __/  |
// | /_/   /_/   \__,_/_/|_|  /_/   /_/_/ /_/\__,_/_/ /_/\___/\___/   |
// |                                                                  |
// ====================================================================
// =========================== CommunalFarm ===========================
// ====================================================================
// Multiple tokens with different reward rates can be emitted
// Multiple teams can set the reward rates for their token(s)
// Apes together strong

// Frax Finance: https://github.com/FraxFinance

// Primary Author(s)
// Travis Moore: https://github.com/FortisFortuna

// Reviewer(s) / Contributor(s)
// Jason Huan: https://github.com/jasonhuan 
// Sam Kazemian: https://github.com/samkazemian
// Saddle Team: https://github.com/saddle-finance
// Fei Team: https://github.com/fei-protocol
// Alchemix Team: https://github.com/alchemix-finance
// Liquity Team: https://github.com/liquity

// Originally inspired by Synthetix.io, but heavily modified by the Frax team
// https://raw.githubusercontent.com/Synthetixio/synthetix/develop/contracts/StakingRewards.sol

import "communal/Math.sol";
import "communal/SafeMath.sol";
import "communal/SafeERC20.sol";
import 'communal/TransferHelper.sol';
import "communal/ReentrancyGuard.sol";

// Inheritance
import "communal/Owned.sol";

contract CommunalFarm is Owned, ReentrancyGuard {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;

    /* ========== STATE VARIABLES ========== */

    // Instances
    IERC20 public stakingToken;
    
    // Constant for various precisions
    uint256 private constant MULTIPLIER_PRECISION = 1e18;

    // Time tracking
    uint256 public periodFinish;
    uint256 public lastUpdateTime;

    // Lock time and multiplier settings
    uint256 public lock_max_multiplier = uint256(3e18); // E18. 1x = e18
    uint256 public lock_time_for_max_multiplier = 1 * 30 * 86400; // 30 days
    uint256 public lock_time_min = 86400; // 1 * 86400  (1 day)

    // Reward addresses, rates, and managers
    mapping(address => address) public rewardManagers; // token addr -> manager addr
    address[] public rewardTokens;
    uint256[] public rewardRates;
    string[] public rewardSymbols;
    mapping(address => uint256) public rewardTokenAddrToIdx; // token addr -> token index
    
    // Reward period
    uint256 public rewardsDuration = 30 * 86400; // 30 * 86400  (30 days)

    // Reward tracking
    uint256[] private rewardsPerTokenStored;
    mapping(address => mapping(uint256 => uint256)) private userRewardsPerTokenPaid; // staker addr -> token id -> paid amount
    mapping(address => mapping(uint256 => uint256)) private rewards; // staker addr -> token id -> reward amount
    mapping(address => uint256) private lastRewardClaimTime; // staker addr -> timestamp

    // Balance tracking
    uint256 private _total_liquidity_locked;
    uint256 private _total_combined_weight;
    mapping(address => uint256) private _locked_liquidity;
    mapping(address => uint256) private _combined_weights;

    // Stake tracking
    mapping(address => LockedStake[]) private lockedStakes;

    // Greylisting of bad addresses
    mapping(address => bool) public greylist; //how long until this one is offensive too?

    // Administrative booleans
    bool public stakesUnlocked; // Release locked stakes in case of emergency
    bool public withdrawalsPaused; // For emergencies
    bool public rewardsCollectionPaused; // For emergencies
    bool public stakingPaused; // For emergencies

    /* ========== STRUCTS ========== */
    
    struct LockedStake {
        bytes32 kek_id;
        uint256 start_timestamp;
        uint256 liquidity;
        uint256 ending_timestamp;
        uint256 lock_multiplier; // 6 decimals of precision. 1x = 1000000
    }

    /* ========== MODIFIERS ========== */

    modifier onlyByOwner() {
        require(msg.sender == owner, "Not the owner");
        _;
    }

    modifier onlyTknMgrs(address reward_token_address) {
        require(msg.sender == owner || isTokenManagerFor(msg.sender, reward_token_address), "Not owner or tkn mgr");
        _;
    }

    modifier notStakingPaused() {
        require(stakingPaused == false, "Staking paused");
        _;
    }

    modifier updateRewardAndBalance(address account, bool sync_too) {
        _updateRewardAndBalance(account, sync_too);
        _;
    }
    
    /* ========== CONSTRUCTOR ========== */

    constructor (
        address _owner,
        address _stakingToken,
        string[] memory _rewardSymbols,
        address[] memory _rewardTokens,
        address[] memory _rewardManagers,
        uint256[] memory _rewardRates
    ) Owned(_owner){
        stakingToken = IERC20(_stakingToken);

        rewardTokens = _rewardTokens;
        rewardRates = _rewardRates;
        rewardSymbols = _rewardSymbols;

        for (uint256 i = 0; i < _rewardTokens.length; i++){ 
            // For fast token address -> token ID lookups later
            rewardTokenAddrToIdx[_rewardTokens[i]] = i;

            // Initialize the stored rewards
            rewardsPerTokenStored.push(0);

            // Initialize the reward managers
            rewardManagers[_rewardTokens[i]] = _rewardManagers[i];
        }

        // Other booleans
        stakesUnlocked = false;

        // Initialization
        lastUpdateTime = block.timestamp;
        periodFinish = block.timestamp.add(rewardsDuration);
    }

    /* ========== VIEWS ========== */

    // Total locked liquidity tokens
    function totalLiquidityLocked() external view returns (uint256) {
        return _total_liquidity_locked;
    }

    // Locked liquidity for a given account
    function lockedLiquidityOf(address account) external view returns (uint256) {
        return _locked_liquidity[account];
    }

    // Total 'balance' used for calculating the percent of the pool the account owns
    // Takes into account the locked stake time multiplier
    function totalCombinedWeight() external view returns (uint256) {
        return _total_combined_weight;
    }

    // Combined weight for a specific account
    function combinedWeightOf(address account) external view returns (uint256) {
        return _combined_weights[account];
    }

    // Calculated the combined weight for an account
    function calcCurCombinedWeight(address account) public view
        returns (
            uint256 old_combined_weight,
            uint256 new_combined_weight
        )
    {
        // Get the old combined weight
        old_combined_weight = _combined_weights[account];

        // Loop through the locked stakes, first by getting the liquidity * lock_multiplier portion
        new_combined_weight = 0;
        for (uint256 i = 0; i < lockedStakes[account].length; i++) {
            LockedStake memory thisStake = lockedStakes[account][i];
            uint256 lock_multiplier = thisStake.lock_multiplier;

            // If the lock is expired
            if (thisStake.ending_timestamp <= block.timestamp) {
                // If the lock expired in the time since the last claim, the weight needs to be proportionately averaged this time
                if (lastRewardClaimTime[account] < thisStake.ending_timestamp){
                    uint256 time_before_expiry = (thisStake.ending_timestamp).sub(lastRewardClaimTime[account]);
                    uint256 time_after_expiry = (block.timestamp).sub(thisStake.ending_timestamp);

                    // Get the weighted-average lock_multiplier
                    uint256 numerator = ((lock_multiplier).mul(time_before_expiry)).add(((MULTIPLIER_PRECISION).mul(time_after_expiry)));
                    lock_multiplier = numerator.div(time_before_expiry.add(time_after_expiry));
                }
                // Otherwise, it needs to just be 1x
                else {
                    lock_multiplier = MULTIPLIER_PRECISION;
                }
            }

            uint256 liquidity = thisStake.liquidity;
            uint256 combined_boosted_amount = liquidity.mul(lock_multiplier).div(MULTIPLIER_PRECISION);
            new_combined_weight = new_combined_weight.add(combined_boosted_amount);
        }
    }

    // All the locked stakes for a given account
    function lockedStakesOf(address account) external view returns (LockedStake[] memory) {
        return lockedStakes[account];
    }

    // All the locked stakes for a given account
    function getRewardSymbols() external view returns (string[] memory) {
        return rewardSymbols;
    }

    // All the reward tokens
    function getAllRewardTokens() external view returns (address[] memory) {
        return rewardTokens;
    }

    // All the reward rates
    function getAllRewardRates() external view returns (uint256[] memory) {
        return rewardRates;
    }
    
    // Multiplier amount, given the length of the lock
    function lockMultiplier(uint256 secs) public view returns (uint256) {
        uint256 lock_multiplier =
            uint256(MULTIPLIER_PRECISION).add(
                secs
                    .mul(lock_max_multiplier.sub(MULTIPLIER_PRECISION))
                    .div(lock_time_for_max_multiplier)
            );
        if (lock_multiplier > lock_max_multiplier) lock_multiplier = lock_max_multiplier;
        return lock_multiplier;
    }

    // Last time the reward was applicable
    function lastTimeRewardApplicable() internal view returns (uint256) {
        return Math.min(block.timestamp, periodFinish);
    }

    // Amount of reward tokens per LP token
    function rewardsPerToken() public view returns (uint256[] memory newRewardsPerTokenStored) {
        if (_total_liquidity_locked == 0 || _total_combined_weight == 0) {
            return rewardsPerTokenStored;
        }
        else {
            newRewardsPerTokenStored = new uint256[](rewardTokens.length);
            for (uint256 i = 0; i < rewardsPerTokenStored.length; i++){ 
                newRewardsPerTokenStored[i] = rewardsPerTokenStored[i].add(
                    lastTimeRewardApplicable().sub(lastUpdateTime).mul(rewardRates[i]).mul(1e18).div(_total_combined_weight)
                );
            }
            return newRewardsPerTokenStored;
        }
    }

    // Amount of reward tokens an account has earned / accrued
    // Note: In the edge-case of one of the account's stake expiring since the last claim, this will
    // return a slightly inflated number
    function earned(address account) public view returns (uint256[] memory new_earned) {
        uint256[] memory reward_arr = rewardsPerToken();
        new_earned = new uint256[](rewardTokens.length);

        if (_combined_weights[account] == 0){
            for (uint256 i = 0; i < rewardTokens.length; i++){ 
                new_earned[i] = 0;
            }
        }
        else {
            for (uint256 i = 0; i < rewardTokens.length; i++){ 
                new_earned[i] = (_combined_weights[account])
                    .mul(reward_arr[i].sub(userRewardsPerTokenPaid[account][i]))
                    .div(1e18)
                    .add(rewards[account][i]);
            }
        }
    }

    // Total reward tokens emitted in the given period
    function getRewardForDuration() external view returns (uint256[] memory rewards_per_duration_arr) {
        rewards_per_duration_arr = new uint256[](rewardRates.length);

        for (uint256 i = 0; i < rewardRates.length; i++){ 
            rewards_per_duration_arr[i] = rewardRates[i].mul(rewardsDuration);
        }
    }

    // See if the caller_addr is a manager for the reward token 
    function isTokenManagerFor(address caller_addr, address reward_token_addr) public view returns (bool){
        if (caller_addr == owner) return true; // Contract owner
        else if (rewardManagers[reward_token_addr] == caller_addr) return true; // Reward manager
        return false; 
    }

    /* ========== MUTATIVE FUNCTIONS ========== */

    function _updateRewardAndBalance(address account, bool sync_too) internal {
        // Need to retro-adjust some things if the period hasn't been renewed, then start a new one
        if (sync_too){
            sync();
        }
        
        if (account != address(0)) {
            // To keep the math correct, the user's combined weight must be recomputed
            (   
                uint256 old_combined_weight,
                uint256 new_combined_weight
            ) = calcCurCombinedWeight(account);

            // Calculate the earnings first
            _syncEarned(account);

            // Update the user's and the global combined weights
            if (new_combined_weight >= old_combined_weight) {
                uint256 weight_diff = new_combined_weight.sub(old_combined_weight);
                _total_combined_weight = _total_combined_weight.add(weight_diff);
                _combined_weights[account] = old_combined_weight.add(weight_diff);
            } else {
                uint256 weight_diff = old_combined_weight.sub(new_combined_weight);
                _total_combined_weight = _total_combined_weight.sub(weight_diff);
                _combined_weights[account] = old_combined_weight.sub(weight_diff);
            }

        }
    }

    function _syncEarned(address account) internal {
        if (account != address(0)) {
            // Calculate the earnings
            uint256[] memory earned_arr = earned(account);

            // Update the rewards array
            for (uint256 i = 0; i < earned_arr.length; i++){ 
                rewards[account][i] = earned_arr[i];
            }

            // Update the rewards paid array
            for (uint256 i = 0; i < earned_arr.length; i++){ 
                userRewardsPerTokenPaid[account][i] = rewardsPerTokenStored[i];
            }
        }
    }

    // Two different stake functions are needed because of delegateCall and msg.sender issues
    function stakeLocked(uint256 liquidity, uint256 secs) nonReentrant public {
        _stakeLocked(msg.sender, msg.sender, liquidity, secs, block.timestamp);
    }

    // If this were not internal, and source_address had an infinite approve, this could be exploitable
    // (pull funds from source_address and stake for an arbitrary staker_address)
    function _stakeLocked(
        address staker_address, 
        address source_address, 
        uint256 liquidity, 
        uint256 secs,
        uint256 start_timestamp
    ) internal updateRewardAndBalance(staker_address, true) {
        require(!stakingPaused, "Staking paused");
        require(liquidity > 0, "Must stake more than zero");
        require(greylist[staker_address] == false, "Address has been greylisted");
        require(secs >= lock_time_min, "Minimum stake time not met");
        require(secs <= lock_time_for_max_multiplier,"Trying to lock for too long");

        uint256 lock_multiplier = lockMultiplier(secs);
        bytes32 kek_id = keccak256(abi.encodePacked(staker_address, start_timestamp, liquidity, _locked_liquidity[staker_address]));
        lockedStakes[staker_address].push(LockedStake(
            kek_id,
            start_timestamp,
            liquidity,
            start_timestamp.add(secs),
            lock_multiplier
        ));

        // Pull the tokens from the source_address
        //TODO: do we even need this if we're dealing with Sushi LP not saddle?
        TransferHelper.safeTransferFrom(address(stakingToken), source_address, address(this), liquidity);

        // Update liquidities
        _total_liquidity_locked = _total_liquidity_locked.add(liquidity);
        _locked_liquidity[staker_address] = _locked_liquidity[staker_address].add(liquidity);

        // Need to call to update the combined weights
        _updateRewardAndBalance(staker_address, false);

        // Needed for edge case if the staker only claims once, and after the lock expired
        if (lastRewardClaimTime[staker_address] == 0) lastRewardClaimTime[staker_address] = block.timestamp;

        emit StakeLocked(staker_address, liquidity, secs, kek_id, source_address);
    }

    // Two different withdrawLocked functions are needed because of delegateCall and msg.sender issues
    function withdrawLocked(bytes32 kek_id) nonReentrant public {
        require(withdrawalsPaused == false, "Withdrawals paused");
        _withdrawLocked(msg.sender, msg.sender, kek_id);
    }

    // No withdrawer == msg.sender check needed since this is only internally callable and the checks are done in the wrapper
    // functions like withdraw()
    function _withdrawLocked(address staker_address, address destination_address, bytes32 kek_id) internal  {
        // Collect rewards first and then update the balances
        _getReward(staker_address, destination_address);

        LockedStake memory thisStake;
        thisStake.liquidity = 0;
        uint theArrayIndex;
        for (uint256 i = 0; i < lockedStakes[staker_address].length; i++){ 
            if (kek_id == lockedStakes[staker_address][i].kek_id){
                thisStake = lockedStakes[staker_address][i];
                theArrayIndex = i;
                break;
            }
        }
        require(thisStake.kek_id == kek_id, "Stake not found");
        require(block.timestamp >= thisStake.ending_timestamp || stakesUnlocked == true, "Stake is still locked!");

        uint256 liquidity = thisStake.liquidity;

        if (liquidity > 0) {
            // Update liquidities
            _total_liquidity_locked = _total_liquidity_locked.sub(liquidity);
            _locked_liquidity[staker_address] = _locked_liquidity[staker_address].sub(liquidity);

            // Remove the stake from the array
            delete lockedStakes[staker_address][theArrayIndex];

            // Need to call to update the combined weights
            _updateRewardAndBalance(staker_address, false);

            // Give the tokens to the destination_address
            // Should throw if insufficient balance
            stakingToken.transfer(destination_address, liquidity);

            emit WithdrawLocked(staker_address, liquidity, kek_id, destination_address);
        }

    }
    
    // Two different getReward functions are needed because of delegateCall and msg.sender issues
    function getReward() external nonReentrant returns (uint256[] memory) {
        require(rewardsCollectionPaused == false,"Rewards collection paused");
        return _getReward(msg.sender, msg.sender);
    }

    // No withdrawer == msg.sender check needed since this is only internally callable
    function _getReward(address rewardee, address destination_address) internal updateRewardAndBalance(rewardee, true) returns (uint256[] memory rewards_before) {
        // Update the rewards array and distribute rewards
        rewards_before = new uint256[](rewardTokens.length);

        for (uint256 i = 0; i < rewardTokens.length; i++){ 
            rewards_before[i] = rewards[rewardee][i];
            rewards[rewardee][i] = 0;
            //use SafeERC20.transfer
            IERC20(rewardTokens[i]).transfer(destination_address, rewards_before[i]);
            emit RewardPaid(rewardee, rewards_before[i], rewardTokens[i], destination_address);
        }

        lastRewardClaimTime[rewardee] = block.timestamp;
    }

    // If the period expired, renew it
    function retroCatchUp() internal {
        // Failsafe check
        require(block.timestamp > periodFinish, "Period has not expired yet!");

        // Ensure the provided reward amount is not more than the balance in the contract.
        // This keeps the reward rate in the right range, preventing overflows due to
        // very high values of rewardRate in the earned and rewardsPerToken functions;
        // Reward + leftover must be less than 2^256 / 10^18 to avoid overflow.
        uint256 num_periods_elapsed = uint256(block.timestamp.sub(periodFinish)) / rewardsDuration; // Floor division to the nearest period
        
        // Make sure there are enough tokens to renew the reward period
        for (uint256 i = 0; i < rewardTokens.length; i++){ 
            require(rewardRates[i].mul(rewardsDuration).mul(num_periods_elapsed + 1) <= IERC20(rewardTokens[i]).balanceOf(address(this)), string(abi.encodePacked("Not enough reward tokens available: ", rewardTokens[i])) );
        }
        
        // uint256 old_lastUpdateTime = lastUpdateTime;
        // uint256 new_lastUpdateTime = block.timestamp;

        // lastUpdateTime = periodFinish;
        periodFinish = periodFinish.add((num_periods_elapsed.add(1)).mul(rewardsDuration));

        _updateStoredRewardsAndTime();

        emit RewardsPeriodRenewed(address(stakingToken));
    }

    function _updateStoredRewardsAndTime() internal {
        // Get the rewards
        uint256[] memory rewards_per_token = rewardsPerToken();

        // Update the rewardsPerTokenStored
        for (uint256 i = 0; i < rewardsPerTokenStored.length; i++){ 
            rewardsPerTokenStored[i] = rewards_per_token[i];
        }

        // Update the last stored time
        lastUpdateTime = lastTimeRewardApplicable();
    }

    function sync() public {
        if (block.timestamp > periodFinish) {
            retroCatchUp();
        }
        else {
            _updateStoredRewardsAndTime();
        }
    }

    /* ========== RESTRICTED FUNCTIONS ========== */

    // Added to support recovering LP Rewards and other mistaken tokens from other systems to be distributed to holders
    function recoverERC20(address tokenAddress, uint256 tokenAmount) external onlyTknMgrs(tokenAddress) {
        // Cannot rug the staking / LP tokens
        require(tokenAddress != address(stakingToken), "Cannot rug staking / LP tokens");

        // Check if the desired token is a reward token
        bool isRewardToken = false;
        for (uint256 i = 0; i < rewardTokens.length; i++){ 
            if (rewardTokens[i] == tokenAddress) {
                isRewardToken = true;
                break;
            }
        }

        // Only the reward managers can take back their reward tokens
        if (isRewardToken && rewardManagers[tokenAddress] == msg.sender){
            IERC20(tokenAddress).transfer(msg.sender, tokenAmount);
            emit Recovered(msg.sender, tokenAddress, tokenAmount);
            return;
        }

        // Other tokens, like airdrops or accidental deposits, can be withdrawn by the owner
        else if (!isRewardToken && (msg.sender == owner)){
            IERC20(tokenAddress).transfer(msg.sender, tokenAmount);
            emit Recovered(msg.sender, tokenAddress, tokenAmount);
            return;
        }

        // If none of the above conditions are true
        else {
            revert("No valid tokens to recover");
        }
    }

    function setRewardsDuration(uint256 _rewardsDuration) external onlyByOwner {
        require(_rewardsDuration >= 86400, "Rewards duration too short");
        require(
            periodFinish == 0 || block.timestamp > periodFinish,
            "Reward period incomplete"
        );
        rewardsDuration = _rewardsDuration;
        emit RewardsDurationUpdated(rewardsDuration);
    }

    function setMultipliers(uint256 _lock_max_multiplier) external onlyByOwner {
        require(_lock_max_multiplier >= uint256(1e18), "Multiplier must be greater than or equal to 1e18");
        lock_max_multiplier = _lock_max_multiplier;
        emit LockedStakeMaxMultiplierUpdated(lock_max_multiplier);
    }

    function setLockedStakeTimeForMinAndMaxMultiplier(uint256 _lock_time_for_max_multiplier, uint256 _lock_time_min) external onlyByOwner {
        require(_lock_time_for_max_multiplier >= 1, "Mul max time must be >= 1");
        require(_lock_time_min >= 1, "Mul min time must be >= 1");

        lock_time_for_max_multiplier = _lock_time_for_max_multiplier;
        lock_time_min = _lock_time_min;

        emit LockedStakeTimeForMaxMultiplier(lock_time_for_max_multiplier);
        emit LockedStakeMinTime(_lock_time_min);
    }

    function greylistAddress(address _address) external onlyByOwner {
        greylist[_address] = !(greylist[_address]);
    }

    function unlockStakes() external onlyByOwner {
        stakesUnlocked = !stakesUnlocked;
    }

    function toggleStaking() external onlyByOwner {
        stakingPaused = !stakingPaused;
    }

    function toggleWithdrawals() external onlyByOwner {
        withdrawalsPaused = !withdrawalsPaused;
    }

    function toggleRewardsCollection() external onlyByOwner {
        rewardsCollectionPaused = !rewardsCollectionPaused;
    }

    // The owner or the reward token managers can set reward rates 
    function setRewardRate(address reward_token_address, uint256 new_rate, bool sync_too) external onlyTknMgrs(reward_token_address) {
        rewardRates[rewardTokenAddrToIdx[reward_token_address]] = new_rate;
        
        if (sync_too){
            sync();
        }
    }

    // The owner or the reward token managers can change managers
    function changeTokenManager(address reward_token_address, address new_manager_address) external onlyTknMgrs(reward_token_address) {
        rewardManagers[reward_token_address] = new_manager_address;
    }

    /* ========== EVENTS ========== */

    event StakeLocked(address indexed user, uint256 amount, uint256 secs, bytes32 kek_id, address source_address);
    event WithdrawLocked(address indexed user, uint256 amount, bytes32 kek_id, address destination_address);
    event RewardPaid(address indexed user, uint256 reward, address token_address, address destination_address);
    event RewardsDurationUpdated(uint256 newDuration);
    event Recovered(address destination_address, address token, uint256 amount);
    event RewardsPeriodRenewed(address token);
    event LockedStakeMaxMultiplierUpdated(uint256 multiplier);
    event LockedStakeTimeForMaxMultiplier(uint256 secs);
    event LockedStakeMinTime(uint256 secs);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.13;

/// Common mathematical functions used in both SD59x18 and UD60x18. Note that these global functions do not
/// always operate with SD59x18 and UD60x18 numbers.

/*//////////////////////////////////////////////////////////////////////////
                                CUSTOM ERRORS
//////////////////////////////////////////////////////////////////////////*/

/// @notice Emitted when the ending result in the fixed-point version of `mulDiv` would overflow uint256.
error PRBMath__MulDiv18Overflow(uint256 x, uint256 y);

/// @notice Emitted when the ending result in `mulDiv` would overflow uint256.
error PRBMath__MulDivOverflow(uint256 x, uint256 y, uint256 denominator);

/// @notice Emitted when attempting to run `mulDiv` with one of the inputs `type(int256).min`.
error PRBMath__MulDivSignedInputTooSmall();

/// @notice Emitted when the ending result in the signed version of `mulDiv` would overflow int256.
error PRBMath__MulDivSignedOverflow(int256 x, int256 y);

/*//////////////////////////////////////////////////////////////////////////
                                    CONSTANTS
//////////////////////////////////////////////////////////////////////////*/

/// @dev How many trailing decimals can be represented.
uint256 constant UNIT = 1e18;

/// @dev Largest power of two that is a divisor of `UNIT`.
uint256 constant UNIT_LPOTD = 262144;

/// @dev The `UNIT` number inverted mod 2^256.
uint256 constant UNIT_INVERSE = 78156646155174841979727994598816262306175212592076161876661_508869554232690281;

/*//////////////////////////////////////////////////////////////////////////
                                    FUNCTIONS
//////////////////////////////////////////////////////////////////////////*/

/// @notice Finds the zero-based index of the first one in the binary representation of x.
/// @dev See the note on msb in the "Find First Set" Wikipedia article https://en.wikipedia.org/wiki/Find_first_set
///
/// Each of the steps in this implementation is equivalent to this high-level code:
///
/// ```solidity
/// if (x >= 2 ** 128) {
///     x >>= 128;
///     result += 128;
/// }
/// ```
///
/// Where 128 is swapped with each respective power of two factor. See the full high-level implementation here:
/// https://gist.github.com/paulrberg/f932f8693f2733e30c4d479e8e980948
///
/// A list of the Yul instructions used below:
/// - "gt" is "greater than"
/// - "or" is the OR bitwise operator
/// - "shl" is "shift left"
/// - "shr" is "shift right"
///
/// @param x The uint256 number for which to find the index of the most significant bit.
/// @return result The index of the most significant bit as an uint256.
function msb(uint256 x) pure returns (uint256 result) {
    // 2^128
    assembly {
        let factor := shl(7, gt(x, 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF))
        x := shr(factor, x)
        result := or(result, factor)
    }
    // 2^64
    assembly {
        let factor := shl(6, gt(x, 0xFFFFFFFFFFFFFFFF))
        x := shr(factor, x)
        result := or(result, factor)
    }
    // 2^32
    assembly {
        let factor := shl(5, gt(x, 0xFFFFFFFF))
        x := shr(factor, x)
        result := or(result, factor)
    }
    // 2^16
    assembly {
        let factor := shl(4, gt(x, 0xFFFF))
        x := shr(factor, x)
        result := or(result, factor)
    }
    // 2^8
    assembly {
        let factor := shl(3, gt(x, 0xFF))
        x := shr(factor, x)
        result := or(result, factor)
    }
    // 2^4
    assembly {
        let factor := shl(2, gt(x, 0xF))
        x := shr(factor, x)
        result := or(result, factor)
    }
    // 2^2
    assembly {
        let factor := shl(1, gt(x, 0x3))
        x := shr(factor, x)
        result := or(result, factor)
    }
    // 2^1
    // No need to shift x any more.
    assembly {
        let factor := gt(x, 0x1)
        result := or(result, factor)
    }
}

/// @notice Calculates floor(x*y÷denominator) with full precision.
///
/// @dev Credits to Remco Bloemen under MIT license https://xn--2-umb.com/21/muldiv.
///
/// Requirements:
/// - The denominator cannot be zero.
/// - The result must fit within uint256.
///
/// Caveats:
/// - This function does not work with fixed-point numbers.
///
/// @param x The multiplicand as an uint256.
/// @param y The multiplier as an uint256.
/// @param denominator The divisor as an uint256.
/// @return result The result as an uint256.
function mulDiv(uint256 x, uint256 y, uint256 denominator) pure returns (uint256 result) {
    // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
    // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
    // variables such that product = prod1 * 2^256 + prod0.
    uint256 prod0; // Least significant 256 bits of the product
    uint256 prod1; // Most significant 256 bits of the product
    assembly {
        let mm := mulmod(x, y, not(0))
        prod0 := mul(x, y)
        prod1 := sub(sub(mm, prod0), lt(mm, prod0))
    }

    // Handle non-overflow cases, 256 by 256 division.
    if (prod1 == 0) {
        unchecked {
            return prod0 / denominator;
        }
    }

    // Make sure the result is less than 2^256. Also prevents denominator == 0.
    if (prod1 >= denominator) {
        revert PRBMath__MulDivOverflow(x, y, denominator);
    }

    ///////////////////////////////////////////////
    // 512 by 256 division.
    ///////////////////////////////////////////////

    // Make division exact by subtracting the remainder from [prod1 prod0].
    uint256 remainder;
    assembly {
        // Compute remainder using the mulmod Yul instruction.
        remainder := mulmod(x, y, denominator)

        // Subtract 256 bit number from 512 bit number.
        prod1 := sub(prod1, gt(remainder, prod0))
        prod0 := sub(prod0, remainder)
    }

    // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
    // See https://cs.stackexchange.com/q/138556/92363.
    unchecked {
        // Does not overflow because the denominator cannot be zero at this stage in the function.
        uint256 lpotdod = denominator & (~denominator + 1);
        assembly {
            // Divide denominator by lpotdod.
            denominator := div(denominator, lpotdod)

            // Divide [prod1 prod0] by lpotdod.
            prod0 := div(prod0, lpotdod)

            // Flip lpotdod such that it is 2^256 / lpotdod. If lpotdod is zero, then it becomes one.
            lpotdod := add(div(sub(0, lpotdod), lpotdod), 1)
        }

        // Shift in bits from prod1 into prod0.
        prod0 |= prod1 * lpotdod;

        // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
        // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
        // four bits. That is, denominator * inv = 1 mod 2^4.
        uint256 inverse = (3 * denominator) ^ 2;

        // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
        // in modular arithmetic, doubling the correct bits in each step.
        inverse *= 2 - denominator * inverse; // inverse mod 2^8
        inverse *= 2 - denominator * inverse; // inverse mod 2^16
        inverse *= 2 - denominator * inverse; // inverse mod 2^32
        inverse *= 2 - denominator * inverse; // inverse mod 2^64
        inverse *= 2 - denominator * inverse; // inverse mod 2^128
        inverse *= 2 - denominator * inverse; // inverse mod 2^256

        // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
        // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
        // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
        // is no longer required.
        result = prod0 * inverse;
    }
}

/// @notice Calculates floor(x*y÷1e18) with full precision.
///
/// @dev Variant of `mulDiv` with constant folding, i.e. in which the denominator is always 1e18. Before returning the
/// final result, we add 1 if `(x * y) % UNIT >= HALF_UNIT`. Without this adjustment, 6.6e-19 would be truncated to 0
/// instead of being rounded to 1e-18. See "Listing 6" and text above it at https://accu.org/index.php/journals/1717.
///
/// Requirements:
/// - The result must fit within uint256.
///
/// Caveats:
/// - The body is purposely left uncommented; to understand how this works, see the NatSpec comments in `mulDiv`.
/// - It is assumed that the result can never be `type(uint256).max` when x and y solve the following two equations:
///     1. x * y = type(uint256).max * UNIT
///     2. (x * y) % UNIT >= UNIT / 2
///
/// @param x The multiplicand as an unsigned 60.18-decimal fixed-point number.
/// @param y The multiplier as an unsigned 60.18-decimal fixed-point number.
/// @return result The result as an unsigned 60.18-decimal fixed-point number.
function mulDiv18(uint256 x, uint256 y) pure returns (uint256 result) {
    uint256 prod0;
    uint256 prod1;
    assembly {
        let mm := mulmod(x, y, not(0))
        prod0 := mul(x, y)
        prod1 := sub(sub(mm, prod0), lt(mm, prod0))
    }

    if (prod1 >= UNIT) {
        revert PRBMath__MulDiv18Overflow(x, y);
    }

    uint256 remainder;
    assembly {
        remainder := mulmod(x, y, UNIT)
    }

    if (prod1 == 0) {
        unchecked {
            return prod0 / UNIT;
        }
    }

    assembly {
        result := mul(
            or(
                div(sub(prod0, remainder), UNIT_LPOTD),
                mul(sub(prod1, gt(remainder, prod0)), add(div(sub(0, UNIT_LPOTD), UNIT_LPOTD), 1))
            ),
            UNIT_INVERSE
        )
    }
}

/// @notice Calculates floor(x*y÷denominator) with full precision.
///
/// @dev An extension of `mulDiv` for signed numbers. Works by computing the signs and the absolute values separately.
///
/// Requirements:
/// - None of the inputs can be `type(int256).min`.
/// - The result must fit within int256.
///
/// @param x The multiplicand as an int256.
/// @param y The multiplier as an int256.
/// @param denominator The divisor as an int256.
/// @return result The result as an int256.
function mulDivSigned(int256 x, int256 y, int256 denominator) pure returns (int256 result) {
    if (x == type(int256).min || y == type(int256).min || denominator == type(int256).min) {
        revert PRBMath__MulDivSignedInputTooSmall();
    }

    // Get hold of the absolute values of x, y and the denominator.
    uint256 absX;
    uint256 absY;
    uint256 absD;
    unchecked {
        absX = x < 0 ? uint256(-x) : uint256(x);
        absY = y < 0 ? uint256(-y) : uint256(y);
        absD = denominator < 0 ? uint256(-denominator) : uint256(denominator);
    }

    // Compute the absolute value of (x*y)÷denominator. The result must fit within int256.
    uint256 rAbs = mulDiv(absX, absY, absD);
    if (rAbs > uint256(type(int256).max)) {
        revert PRBMath__MulDivSignedOverflow(x, y);
    }

    // Get the signs of x, y and the denominator.
    uint256 sx;
    uint256 sy;
    uint256 sd;
    assembly {
        // This works thanks to two's complement.
        // "sgt" stands for "signed greater than" and "sub(0,1)" is max uint256.
        sx := sgt(x, sub(0, 1))
        sy := sgt(y, sub(0, 1))
        sd := sgt(denominator, sub(0, 1))
    }

    // XOR over sx, sy and sd. What this does is to check whether there are 1 or 3 negative signs in the inputs.
    // If there are, the result should be negative. Otherwise, it should be positive.
    unchecked {
        result = sx ^ sy ^ sd == 0 ? -int256(rAbs) : int256(rAbs);
    }
}

/// @notice Calculates the binary exponent of x using the binary fraction method.
/// @dev Has to use 192.64-bit fixed-point numbers.
/// See https://ethereum.stackexchange.com/a/96594/24693.
/// @param x The exponent as an unsigned 192.64-bit fixed-point number.
/// @return result The result as an unsigned 60.18-decimal fixed-point number.
function prbExp2(uint256 x) pure returns (uint256 result) {
    unchecked {
        // Start from 0.5 in the 192.64-bit fixed-point format.
        result = 0x800000000000000000000000000000000000000000000000;

        // Multiply the result by root(2, 2^-i) when the bit at position i is 1. None of the intermediary results overflows
        // because the initial result is 2^191 and all magic factors are less than 2^65.
        if (x & 0xFF00000000000000 > 0) {
            if (x & 0x8000000000000000 > 0) {
                result = (result * 0x16A09E667F3BCC909) >> 64;
            }
            if (x & 0x4000000000000000 > 0) {
                result = (result * 0x1306FE0A31B7152DF) >> 64;
            }
            if (x & 0x2000000000000000 > 0) {
                result = (result * 0x1172B83C7D517ADCE) >> 64;
            }
            if (x & 0x1000000000000000 > 0) {
                result = (result * 0x10B5586CF9890F62A) >> 64;
            }
            if (x & 0x800000000000000 > 0) {
                result = (result * 0x1059B0D31585743AE) >> 64;
            }
            if (x & 0x400000000000000 > 0) {
                result = (result * 0x102C9A3E778060EE7) >> 64;
            }
            if (x & 0x200000000000000 > 0) {
                result = (result * 0x10163DA9FB33356D8) >> 64;
            }
            if (x & 0x100000000000000 > 0) {
                result = (result * 0x100B1AFA5ABCBED61) >> 64;
            }
        }

        if (x & 0xFF000000000000 > 0) {
            if (x & 0x80000000000000 > 0) {
                result = (result * 0x10058C86DA1C09EA2) >> 64;
            }
            if (x & 0x40000000000000 > 0) {
                result = (result * 0x1002C605E2E8CEC50) >> 64;
            }
            if (x & 0x20000000000000 > 0) {
                result = (result * 0x100162F3904051FA1) >> 64;
            }
            if (x & 0x10000000000000 > 0) {
                result = (result * 0x1000B175EFFDC76BA) >> 64;
            }
            if (x & 0x8000000000000 > 0) {
                result = (result * 0x100058BA01FB9F96D) >> 64;
            }
            if (x & 0x4000000000000 > 0) {
                result = (result * 0x10002C5CC37DA9492) >> 64;
            }
            if (x & 0x2000000000000 > 0) {
                result = (result * 0x1000162E525EE0547) >> 64;
            }
            if (x & 0x1000000000000 > 0) {
                result = (result * 0x10000B17255775C04) >> 64;
            }
        }

        if (x & 0xFF0000000000 > 0) {
            if (x & 0x800000000000 > 0) {
                result = (result * 0x1000058B91B5BC9AE) >> 64;
            }
            if (x & 0x400000000000 > 0) {
                result = (result * 0x100002C5C89D5EC6D) >> 64;
            }
            if (x & 0x200000000000 > 0) {
                result = (result * 0x10000162E43F4F831) >> 64;
            }
            if (x & 0x100000000000 > 0) {
                result = (result * 0x100000B1721BCFC9A) >> 64;
            }
            if (x & 0x80000000000 > 0) {
                result = (result * 0x10000058B90CF1E6E) >> 64;
            }
            if (x & 0x40000000000 > 0) {
                result = (result * 0x1000002C5C863B73F) >> 64;
            }
            if (x & 0x20000000000 > 0) {
                result = (result * 0x100000162E430E5A2) >> 64;
            }
            if (x & 0x10000000000 > 0) {
                result = (result * 0x1000000B172183551) >> 64;
            }
        }

        if (x & 0xFF00000000 > 0) {
            if (x & 0x8000000000 > 0) {
                result = (result * 0x100000058B90C0B49) >> 64;
            }
            if (x & 0x4000000000 > 0) {
                result = (result * 0x10000002C5C8601CC) >> 64;
            }
            if (x & 0x2000000000 > 0) {
                result = (result * 0x1000000162E42FFF0) >> 64;
            }
            if (x & 0x1000000000 > 0) {
                result = (result * 0x10000000B17217FBB) >> 64;
            }
            if (x & 0x800000000 > 0) {
                result = (result * 0x1000000058B90BFCE) >> 64;
            }
            if (x & 0x400000000 > 0) {
                result = (result * 0x100000002C5C85FE3) >> 64;
            }
            if (x & 0x200000000 > 0) {
                result = (result * 0x10000000162E42FF1) >> 64;
            }
            if (x & 0x100000000 > 0) {
                result = (result * 0x100000000B17217F8) >> 64;
            }
        }

        if (x & 0xFF00000000 > 0) {
            if (x & 0x80000000 > 0) {
                result = (result * 0x10000000058B90BFC) >> 64;
            }
            if (x & 0x40000000 > 0) {
                result = (result * 0x1000000002C5C85FE) >> 64;
            }
            if (x & 0x20000000 > 0) {
                result = (result * 0x100000000162E42FF) >> 64;
            }
            if (x & 0x10000000 > 0) {
                result = (result * 0x1000000000B17217F) >> 64;
            }
            if (x & 0x8000000 > 0) {
                result = (result * 0x100000000058B90C0) >> 64;
            }
            if (x & 0x4000000 > 0) {
                result = (result * 0x10000000002C5C860) >> 64;
            }
            if (x & 0x2000000 > 0) {
                result = (result * 0x1000000000162E430) >> 64;
            }
            if (x & 0x1000000 > 0) {
                result = (result * 0x10000000000B17218) >> 64;
            }
        }

        if (x & 0xFF0000 > 0) {
            if (x & 0x800000 > 0) {
                result = (result * 0x1000000000058B90C) >> 64;
            }
            if (x & 0x400000 > 0) {
                result = (result * 0x100000000002C5C86) >> 64;
            }
            if (x & 0x200000 > 0) {
                result = (result * 0x10000000000162E43) >> 64;
            }
            if (x & 0x100000 > 0) {
                result = (result * 0x100000000000B1721) >> 64;
            }
            if (x & 0x80000 > 0) {
                result = (result * 0x10000000000058B91) >> 64;
            }
            if (x & 0x40000 > 0) {
                result = (result * 0x1000000000002C5C8) >> 64;
            }
            if (x & 0x20000 > 0) {
                result = (result * 0x100000000000162E4) >> 64;
            }
            if (x & 0x10000 > 0) {
                result = (result * 0x1000000000000B172) >> 64;
            }
        }

        if (x & 0xFF00 > 0) {
            if (x & 0x8000 > 0) {
                result = (result * 0x100000000000058B9) >> 64;
            }
            if (x & 0x4000 > 0) {
                result = (result * 0x10000000000002C5D) >> 64;
            }
            if (x & 0x2000 > 0) {
                result = (result * 0x1000000000000162E) >> 64;
            }
            if (x & 0x1000 > 0) {
                result = (result * 0x10000000000000B17) >> 64;
            }
            if (x & 0x800 > 0) {
                result = (result * 0x1000000000000058C) >> 64;
            }
            if (x & 0x400 > 0) {
                result = (result * 0x100000000000002C6) >> 64;
            }
            if (x & 0x200 > 0) {
                result = (result * 0x10000000000000163) >> 64;
            }
            if (x & 0x100 > 0) {
                result = (result * 0x100000000000000B1) >> 64;
            }
        }

        if (x & 0xFF > 0) {
            if (x & 0x80 > 0) {
                result = (result * 0x10000000000000059) >> 64;
            }
            if (x & 0x40 > 0) {
                result = (result * 0x1000000000000002C) >> 64;
            }
            if (x & 0x20 > 0) {
                result = (result * 0x10000000000000016) >> 64;
            }
            if (x & 0x10 > 0) {
                result = (result * 0x1000000000000000B) >> 64;
            }
            if (x & 0x8 > 0) {
                result = (result * 0x10000000000000006) >> 64;
            }
            if (x & 0x4 > 0) {
                result = (result * 0x10000000000000003) >> 64;
            }
            if (x & 0x2 > 0) {
                result = (result * 0x10000000000000001) >> 64;
            }
            if (x & 0x1 > 0) {
                result = (result * 0x10000000000000001) >> 64;
            }
        }

        // We're doing two things at the same time:
        //
        //   1. Multiply the result by 2^n + 1, where "2^n" is the integer part and the one is added to account for
        //      the fact that we initially set the result to 0.5. This is accomplished by subtracting from 191
        //      rather than 192.
        //   2. Convert the result to the unsigned 60.18-decimal fixed-point format.
        //
        // This works because 2^(191-ip) = 2^ip / 2^191, where "ip" is the integer part "2^n".
        result *= UNIT;
        result >>= (191 - (x >> 64));
    }
}

/// @notice Calculates the square root of x, rounding down if x is not a perfect square.
/// @dev Uses the Babylonian method https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method.
/// Credits to OpenZeppelin for the explanations in code comments below.
///
/// Caveats:
/// - This function does not work with fixed-point numbers.
///
/// @param x The uint256 number for which to calculate the square root.
/// @return result The result as an uint256.
function prbSqrt(uint256 x) pure returns (uint256 result) {
    if (x == 0) {
        return 0;
    }

    // For our first guess, we get the biggest power of 2 which is smaller than the square root of x.
    //
    // We know that the "msb" (most significant bit) of x is a power of 2 such that we have:
    //
    // $$
    // msb(x) <= x <= 2*msb(x)$
    // $$
    //
    // We write $msb(x)$ as $2^k$ and we get:
    //
    // $$
    // k = log_2(x)
    // $$
    //
    // Thus we can write the initial inequality as:
    //
    // $$
    // 2^{log_2(x)} <= x <= 2*2^{log_2(x)+1} \\
    // sqrt(2^k) <= sqrt(x) < sqrt(2^{k+1}) \\
    // 2^{k/2} <= sqrt(x) < 2^{(k+1)/2} <= 2^{(k/2)+1}
    // $$
    //
    // Consequently, $2^{log_2(x) /2}` is a good first approximation of sqrt(x) with at least one correct bit.
    uint256 xAux = uint256(x);
    result = 1;
    if (xAux >= 2 ** 128) {
        xAux >>= 128;
        result <<= 64;
    }
    if (xAux >= 2 ** 64) {
        xAux >>= 64;
        result <<= 32;
    }
    if (xAux >= 2 ** 32) {
        xAux >>= 32;
        result <<= 16;
    }
    if (xAux >= 2 ** 16) {
        xAux >>= 16;
        result <<= 8;
    }
    if (xAux >= 2 ** 8) {
        xAux >>= 8;
        result <<= 4;
    }
    if (xAux >= 2 ** 4) {
        xAux >>= 4;
        result <<= 2;
    }
    if (xAux >= 2 ** 2) {
        result <<= 1;
    }

    // At this point, `result` is an estimation with at least one bit of precision. We know the true value has at
    // most 128 bits, since  it is the square root of a uint256. Newton's method converges quadratically (precision
    // doubles at every iteration). We thus need at most 7 iteration to turn our partial result with one bit of
    // precision into the expected uint128 result.
    unchecked {
        result = (result + x / result) >> 1;
        result = (result + x / result) >> 1;
        result = (result + x / result) >> 1;
        result = (result + x / result) >> 1;
        result = (result + x / result) >> 1;
        result = (result + x / result) >> 1;
        result = (result + x / result) >> 1;

        // Round down the result in case x is not a perfect square.
        uint256 roundedDownResult = x / result;
        if (result >= roundedDownResult) {
            result = roundedDownResult;
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Counters.sol)

pragma solidity ^0.8.0;

/**
 * @title Counters
 * @author Matt Condon (@shrugs)
 * @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
 * of elements in a mapping, issuing ERC721 ids, or counting request ids.
 *
 * Include with `using Counters for Counters.Counter;`
 */
library Counters {
    struct Counter {
        // This variable should never be directly accessed by users of the library: interactions must be restricted to
        // the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
        // this feature: see https://github.com/ethereum/solidity/issues/4637
        uint256 _value; // default: 0
    }

    function current(Counter storage counter) internal view returns (uint256) {
        return counter._value;
    }

    function increment(Counter storage counter) internal {
        unchecked {
            counter._value += 1;
        }
    }

    function decrement(Counter storage counter) internal {
        uint256 value = counter._value;
        require(value > 0, "Counter: decrement overflow");
        unchecked {
            counter._value = value - 1;
        }
    }

    function reset(Counter storage counter) internal {
        counter._value = 0;
    }
}

// SPDX-License-Identifier: BUSL-1.1
pragma solidity ^0.8.18;


//An oracle that provides prices for different LSDs
//NOTE: This is the rate quoted by the LSDs contracts, no pricing of market impact and liquidity risk is calculated

interface IsfrxETH { function pricePerShare() external view returns (uint256); }
interface IrETH { function getExchangeRate() external view returns (uint256); }
interface IWStETH { function tokensPerStEth() external view returns (uint256); }
interface IcbETH { function exchangeRate() external view returns (uint256); }
interface IankrETH { function sharesToBonds(uint256) external view returns (uint256); }
interface IswETH { function swETHToETHRate() external view returns (uint256); }

contract Darknet {

    address public constant sfrxETHAddress = 0xac3E018457B222d93114458476f3E3416Abbe38F;
    address public constant rETHAddress = 0xae78736Cd615f374D3085123A210448E74Fc6393;
    address public constant wstETHAddress = 0x7f39C581F595B53c5cb19bD0b3f8dA6c935E2Ca0;
    address public constant cbETHAddress = 0xBe9895146f7AF43049ca1c1AE358B0541Ea49704;
    address public constant wethAddress = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
    address public constant ankrETHAddress = 0xE95A203B1a91a908F9B9CE46459d101078c2c3cb;
    address public constant swETHAddress = 0xf951E335afb289353dc249e82926178EaC7DEd78;

    constructor() {}

    function checkPrice(address lsd) public view returns (uint256) {
        if (lsd == wethAddress)    return 1e18;
        if (lsd == wstETHAddress)  return IWStETH(wstETHAddress).tokensPerStEth();
        if (lsd == sfrxETHAddress) return IsfrxETH(sfrxETHAddress).pricePerShare();
        if (lsd == rETHAddress)    return IrETH(rETHAddress).getExchangeRate();
        if (lsd == cbETHAddress)   return IcbETH(cbETHAddress).exchangeRate();
        if (lsd == ankrETHAddress) return IankrETH(ankrETHAddress).sharesToBonds(1e18);
        if (lsd == swETHAddress)   return IswETH(swETHAddress).swETHToETHRate();
        else revert();
    }

}

pragma solidity ^0.8.18;



contract Darknet2 {
    mapping(address => bytes4) public router;
    mapping(address => bool) private hasArgs;
    address public constant wethAddress = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;

    /* ============ Constructor ============ */
    constructor(
        address[] memory _lsds,
        bytes4[] memory _links,
        bool[] memory _hasArgs
    ) {
        require(_lsds.length == _links.length && _lsds.length == _hasArgs.length, "Array length mismatch");
        for (uint256 i = 0; i < _lsds.length; i++) {
            router[_lsds[i]] = _links[i];
            if (_hasArgs[i]) {
                hasArgs[_lsds[i]] = true;
            }
        }
    }

    function checkPrice(address lsd) public view returns (uint256) {
        if(lsd == wethAddress) {
            return 1e18;
        }

        bytes4 fn_sig = router[lsd];
        bool success;
        bytes memory response;
        if (hasArgs[lsd]) {
            (success, response) = lsd.staticcall(abi.encodePacked(fn_sig, uint256(1e18)));
        } else {
            (success, response) = lsd.staticcall(abi.encodePacked(fn_sig));
        }
        require(success, "Static call failed");
        uint256 price = abi.decode(response, (uint256));
        return price;
    }

}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/cryptography/ECDSA.sol)

pragma solidity ^0.8.0;

import "../Strings.sol";

/**
 * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
 *
 * These functions can be used to verify that a message was signed by the holder
 * of the private keys of a given address.
 */
library ECDSA {
    enum RecoverError {
        NoError,
        InvalidSignature,
        InvalidSignatureLength,
        InvalidSignatureS,
        InvalidSignatureV // Deprecated in v4.8
    }

    function _throwError(RecoverError error) private pure {
        if (error == RecoverError.NoError) {
            return; // no error: do nothing
        } else if (error == RecoverError.InvalidSignature) {
            revert("ECDSA: invalid signature");
        } else if (error == RecoverError.InvalidSignatureLength) {
            revert("ECDSA: invalid signature length");
        } else if (error == RecoverError.InvalidSignatureS) {
            revert("ECDSA: invalid signature 's' value");
        }
    }

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature` or error string. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     *
     * Documentation for signature generation:
     * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
     * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
     *
     * _Available since v4.3._
     */
    function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
        if (signature.length == 65) {
            bytes32 r;
            bytes32 s;
            uint8 v;
            // ecrecover takes the signature parameters, and the only way to get them
            // currently is to use assembly.
            /// @solidity memory-safe-assembly
            assembly {
                r := mload(add(signature, 0x20))
                s := mload(add(signature, 0x40))
                v := byte(0, mload(add(signature, 0x60)))
            }
            return tryRecover(hash, v, r, s);
        } else {
            return (address(0), RecoverError.InvalidSignatureLength);
        }
    }

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature`. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     */
    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, signature);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
     *
     * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
     *
     * _Available since v4.3._
     */
    function tryRecover(
        bytes32 hash,
        bytes32 r,
        bytes32 vs
    ) internal pure returns (address, RecoverError) {
        bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
        uint8 v = uint8((uint256(vs) >> 255) + 27);
        return tryRecover(hash, v, r, s);
    }

    /**
     * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
     *
     * _Available since v4.2._
     */
    function recover(
        bytes32 hash,
        bytes32 r,
        bytes32 vs
    ) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, r, vs);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Overload of {ECDSA-tryRecover} that receives the `v`,
     * `r` and `s` signature fields separately.
     *
     * _Available since v4.3._
     */
    function tryRecover(
        bytes32 hash,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal pure returns (address, RecoverError) {
        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
        // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
        //
        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
        // these malleable signatures as well.
        if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
            return (address(0), RecoverError.InvalidSignatureS);
        }

        // If the signature is valid (and not malleable), return the signer address
        address signer = ecrecover(hash, v, r, s);
        if (signer == address(0)) {
            return (address(0), RecoverError.InvalidSignature);
        }

        return (signer, RecoverError.NoError);
    }

    /**
     * @dev Overload of {ECDSA-recover} that receives the `v`,
     * `r` and `s` signature fields separately.
     */
    function recover(
        bytes32 hash,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, v, r, s);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Returns an Ethereum Signed Message, created from a `hash`. This
     * produces hash corresponding to the one signed with the
     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
     * JSON-RPC method as part of EIP-191.
     *
     * See {recover}.
     */
    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
        // 32 is the length in bytes of hash,
        // enforced by the type signature above
        return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
    }

    /**
     * @dev Returns an Ethereum Signed Message, created from `s`. This
     * produces hash corresponding to the one signed with the
     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
     * JSON-RPC method as part of EIP-191.
     *
     * See {recover}.
     */
    function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(s.length), s));
    }

    /**
     * @dev Returns an Ethereum Signed Typed Data, created from a
     * `domainSeparator` and a `structHash`. This produces hash corresponding
     * to the one signed with the
     * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
     * JSON-RPC method as part of EIP-712.
     *
     * See {recover}.
     */
    function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/cryptography/EIP712.sol)

pragma solidity ^0.8.0;

import "./ECDSA.sol";

/**
 * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
 *
 * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
 * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
 * they need in their contracts using a combination of `abi.encode` and `keccak256`.
 *
 * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
 * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
 * ({_hashTypedDataV4}).
 *
 * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
 * the chain id to protect against replay attacks on an eventual fork of the chain.
 *
 * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
 * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
 *
 * _Available since v3.4._
 */
abstract contract EIP712 {
    /* solhint-disable var-name-mixedcase */
    // Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to
    // invalidate the cached domain separator if the chain id changes.
    bytes32 private immutable _CACHED_DOMAIN_SEPARATOR;
    uint256 private immutable _CACHED_CHAIN_ID;
    address private immutable _CACHED_THIS;

    bytes32 private immutable _HASHED_NAME;
    bytes32 private immutable _HASHED_VERSION;
    bytes32 private immutable _TYPE_HASH;

    /* solhint-enable var-name-mixedcase */

    /**
     * @dev Initializes the domain separator and parameter caches.
     *
     * The meaning of `name` and `version` is specified in
     * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
     *
     * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
     * - `version`: the current major version of the signing domain.
     *
     * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
     * contract upgrade].
     */
    constructor(string memory name, string memory version) {
        bytes32 hashedName = keccak256(bytes(name));
        bytes32 hashedVersion = keccak256(bytes(version));
        bytes32 typeHash = keccak256(
            "EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
        );
        _HASHED_NAME = hashedName;
        _HASHED_VERSION = hashedVersion;
        _CACHED_CHAIN_ID = block.chainid;
        _CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator(typeHash, hashedName, hashedVersion);
        _CACHED_THIS = address(this);
        _TYPE_HASH = typeHash;
    }

    /**
     * @dev Returns the domain separator for the current chain.
     */
    function _domainSeparatorV4() internal view returns (bytes32) {
        if (address(this) == _CACHED_THIS && block.chainid == _CACHED_CHAIN_ID) {
            return _CACHED_DOMAIN_SEPARATOR;
        } else {
            return _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION);
        }
    }

    function _buildDomainSeparator(
        bytes32 typeHash,
        bytes32 nameHash,
        bytes32 versionHash
    ) private view returns (bytes32) {
        return keccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this)));
    }

    /**
     * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
     * function returns the hash of the fully encoded EIP712 message for this domain.
     *
     * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
     *
     * ```solidity
     * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
     *     keccak256("Mail(address to,string contents)"),
     *     mailTo,
     *     keccak256(bytes(mailContents))
     * )));
     * address signer = ECDSA.recover(digest, signature);
     * ```
     */
    function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
        return ECDSA.toTypedDataHash(_domainSeparatorV4(), structHash);
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)

pragma solidity ^0.8.0;

import "./IERC165.sol";

/**
 * @dev Implementation of the {IERC165} interface.
 *
 * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
 * for the additional interface id that will be supported. For example:
 *
 * ```solidity
 * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
 *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
 * }
 * ```
 *
 * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
 */
abstract contract ERC165 is IERC165 {
    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return interfaceId == type(IERC165).interfaceId;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/ERC20.sol)

pragma solidity ^0.8.0;

import "./IERC20.sol";
import "./extensions/IERC20Metadata.sol";
import "../../utils/Context.sol";

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * The default value of {decimals} is 18. To select a different value for
     * {decimals} you should overload it.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5.05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless this function is
     * overridden;
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address to, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
     * `transferFrom`. This is semantically equivalent to an infinite approval.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * NOTE: Does not update the allowance if the current allowance
     * is the maximum `uint256`.
     *
     * Requirements:
     *
     * - `from` and `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     * - the caller must have allowance for ``from``'s tokens of at least
     * `amount`.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual override returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, allowance(owner, spender) + addedValue);
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        address owner = _msgSender();
        uint256 currentAllowance = allowance(owner, spender);
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(owner, spender, currentAllowance - subtractedValue);
        }

        return true;
    }

    /**
     * @dev Moves `amount` of tokens from `from` to `to`.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     */
    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(from, to, amount);

        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
            // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
            // decrementing then incrementing.
            _balances[to] += amount;
        }

        emit Transfer(from, to, amount);

        _afterTokenTransfer(from, to, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply += amount;
        unchecked {
            // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
            _balances[account] += amount;
        }
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
            // Overflow not possible: amount <= accountBalance <= totalSupply.
            _totalSupply -= amount;
        }

        emit Transfer(account, address(0), amount);

        _afterTokenTransfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Updates `owner` s allowance for `spender` based on spent `amount`.
     *
     * Does not update the allowance amount in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Might emit an {Approval} event.
     */
    function _spendAllowance(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked {
                _approve(owner, spender, currentAllowance - amount);
            }
        }
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}

    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * has been transferred to `to`.
     * - when `from` is zero, `amount` tokens have been minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/extensions/ERC20Burnable.sol)

pragma solidity ^0.8.0;

import "../ERC20.sol";
import "../../../utils/Context.sol";

/**
 * @dev Extension of {ERC20} that allows token holders to destroy both their own
 * tokens and those that they have an allowance for, in a way that can be
 * recognized off-chain (via event analysis).
 */
abstract contract ERC20Burnable is Context, ERC20 {
    /**
     * @dev Destroys `amount` tokens from the caller.
     *
     * See {ERC20-_burn}.
     */
    function burn(uint256 amount) public virtual {
        _burn(_msgSender(), amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, deducting from the caller's
     * allowance.
     *
     * See {ERC20-_burn} and {ERC20-allowance}.
     *
     * Requirements:
     *
     * - the caller must have allowance for ``accounts``'s tokens of at least
     * `amount`.
     */
    function burnFrom(address account, uint256 amount) public virtual {
        _spendAllowance(account, _msgSender(), amount);
        _burn(account, amount);
    }
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.6.11;

import "../Common/Context.sol";
import "./IERC20.sol";
import "../Math/SafeMath.sol";
import "../Utils/Address.sol";

// Due to compiling issues, _name, _symbol, and _decimals were removed


/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20Mintable}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20Custom is Context, IERC20 {
    using SafeMath for uint256;

    mapping (address => uint256) internal _balances;

    mapping (address => mapping (address => uint256)) internal _allowances;

    uint256 private _totalSupply;

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view override returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.approve(address spender, uint256 amount)
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20};
     *
     * Requirements:
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for `sender`'s tokens of at least
     * `amount`.
     */
    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }

    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(address sender, address recipient, uint256 amount) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(sender, recipient, amount);

        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements
     *
     * - `to` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from the caller.
     *
     * See {ERC20-_burn}.
     */
    function burn(uint256 amount) public virtual {
        _burn(_msgSender(), amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, deducting from the caller's
     * allowance.
     *
     * See {ERC20-_burn} and {ERC20-allowance}.
     *
     * Requirements:
     *
     * - the caller must have allowance for `accounts`'s tokens of at least
     * `amount`.
     */
    function burnFrom(address account, uint256 amount) public virtual {
        uint256 decreasedAllowance = allowance(account, _msgSender()).sub(amount, "ERC20: burn amount exceeds allowance");

        _approve(account, _msgSender(), decreasedAllowance);
        _burn(account, amount);
    }


    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
     *
     * This is internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`.`amount` is then deducted
     * from the caller's allowance.
     *
     * See {_burn} and {_approve}.
     */
    function _burnFrom(address account, uint256 amount) internal virtual {
        _burn(account, amount);
        _approve(account, _msgSender(), _allowances[account][_msgSender()].sub(amount, "ERC20: burn amount exceeds allowance"));
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of `from`'s tokens
     * will be to transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of `from`'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:using-hooks.adoc[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
}

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

import "openzeppelin-contracts/contracts/token/ERC20/ERC20.sol";
import "openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";
import "openzeppelin-contracts/contracts/token/ERC20/extensions/draft-ERC20Permit.sol";
import "openzeppelin-contracts/contracts/token/ERC20/extensions/ERC20Burnable.sol";
import "communal/Owned.sol";

/// @title Parent contract for frxETH.sol
/** @notice Combines Openzeppelin's ERC20Permit and ERC20Burnable with Synthetix's Owned. 
    Also includes a list of authorized minters */
/// @dev frxETH adheres to EIP-712/EIP-2612 and can use permits
contract ERC20PermitPermissionedMint is ERC20Permit, ERC20Burnable, Owned {
    // Core
    address public timelock_address;

    // Minters
    address[] public minters_array; // Allowed to mint
    mapping(address => bool) public minters; // Mapping is also used for faster verification

    /* ========== CONSTRUCTOR ========== */

    constructor(
        address _creator_address,
        address _timelock_address,
        string memory _name,
        string memory _symbol
    ) 
    ERC20(_name, _symbol)
    ERC20Permit(_name) 
    Owned(_creator_address)
    {
      timelock_address = _timelock_address;
    }


    /* ========== MODIFIERS ========== */

    modifier onlyByOwnGov() {
        require(msg.sender == timelock_address || msg.sender == owner, "Not owner or timelock");
        _;
    }

    modifier onlyMinters() {
       require(minters[msg.sender] == true, "Only minters");
        _;
    } 

    /* ========== RESTRICTED FUNCTIONS ========== */

    // Used by minters when user redeems
    function minter_burn_from(address b_address, uint256 b_amount) public onlyMinters {
        super.burnFrom(b_address, b_amount);
        emit TokenMinterBurned(b_address, msg.sender, b_amount);
    }

    // This function is what other minters will call to mint new tokens 
    function minter_mint(address m_address, uint256 m_amount) public onlyMinters {
        super._mint(m_address, m_amount);
        emit TokenMinterMinted(msg.sender, m_address, m_amount);
    }

    // Adds whitelisted minters 
    function addMinter(address minter_address) public onlyByOwnGov {
        require(minter_address != address(0), "Zero address detected");

        require(minters[minter_address] == false, "Address already exists");
        minters[minter_address] = true; 
        minters_array.push(minter_address);

        emit MinterAdded(minter_address);
    }

    // Remove a minter 
    function removeMinter(address minter_address) public onlyByOwnGov {
        require(minter_address != address(0), "Zero address detected");
        require(minters[minter_address] == true, "Address nonexistant");
        
        // Delete from the mapping
        delete minters[minter_address];

        // 'Delete' from the array by setting the address to 0x0
        for (uint i = 0; i < minters_array.length; i++){ 
            if (minters_array[i] == minter_address) {
                minters_array[i] = address(0); // This will leave a null in the array and keep the indices the same
                break;
            }
        }

        emit MinterRemoved(minter_address);
    }

    function setTimelock(address _timelock_address) public onlyByOwnGov {
        require(_timelock_address != address(0), "Zero address detected"); 
        timelock_address = _timelock_address;
        emit TimelockChanged(_timelock_address);
    }

    /* ========== EVENTS ========== */
    
    event TokenMinterBurned(address indexed from, address indexed to, uint256 amount);
    event TokenMinterMinted(address indexed from, address indexed to, uint256 amount);
    event MinterAdded(address minter_address);
    event MinterRemoved(address minter_address);
    event TimelockChanged(address timelock_address);
}

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.11;

/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.0.0, only sets of type `address` (`AddressSet`) and `uint256`
 * (`UintSet`) are supported.
 */
library EnumerableSet {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Set type with
    // bytes32 values.
    // The Set implementation uses private functions, and user-facing
    // implementations (such as AddressSet) are just wrappers around the
    // underlying Set.
    // This means that we can only create new EnumerableSets for types that fit
    // in bytes32.

    struct Set {
        // Storage of set values
        bytes32[] _values;

        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping (bytes32 => uint256) _indexes;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function _add(Set storage set, bytes32 value) private returns (bool) {
        if (!_contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function _remove(Set storage set, bytes32 value) private returns (bool) {
        // We read and store the value's index to prevent multiple reads from the same storage slot
        uint256 valueIndex = set._indexes[value];

        if (valueIndex != 0) { // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.

            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;

            // When the value to delete is the last one, the swap operation is unnecessary. However, since this occurs
            // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.

            bytes32 lastvalue = set._values[lastIndex];

            // Move the last value to the index where the value to delete is
            set._values[toDeleteIndex] = lastvalue;
            // Update the index for the moved value
            set._indexes[lastvalue] = toDeleteIndex + 1; // All indexes are 1-based

            // Delete the slot where the moved value was stored
            set._values.pop();

            // Delete the index for the deleted slot
            delete set._indexes[value];

            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function _contains(Set storage set, bytes32 value) private view returns (bool) {
        return set._indexes[value] != 0;
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function _length(Set storage set) private view returns (uint256) {
        return set._values.length;
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function _at(Set storage set, uint256 index) private view returns (bytes32) {
        require(set._values.length > index, "EnumerableSet: index out of bounds");
        return set._values[index];
    }

    // AddressSet

    struct AddressSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        return _add(set._inner, bytes32(bytes20(value)));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        return _remove(set._inner, bytes32(bytes20(value)));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return _contains(set._inner, bytes32(bytes20(value)));
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(AddressSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        return address(bytes20(_at(set._inner, index)));
    }


    // UintSet

    struct UintSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(UintSet storage set, uint256 value) internal returns (bool) {
        return _add(set._inner, bytes32(value));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(UintSet storage set, uint256 value) internal returns (bool) {
        return _remove(set._inner, bytes32(value));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(UintSet storage set, uint256 value) internal view returns (bool) {
        return _contains(set._inner, bytes32(value));
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function length(UintSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(UintSet storage set, uint256 index) internal view returns (uint256) {
        return uint256(_at(set._inner, index));
    }
}

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.8.13;
pragma experimental ABIEncoderV2;

// ┬ ┬┌┐┌┌─┐┬ ┬╔═╗╔╦╗╦ ╦
// │ ││││└─┐├─┤║╣  ║ ╠═╣
// └─┘┘└┘└─┘┴ ┴╚═╝ ╩ ╩ ╩
// =======================
// EuclideanFarm.sol
/// @title Modified StakingRewards from Frax/Synthetix with a "coordination multiplier"
/// @author @EIP-A1tair
/// @notice Allows users to stake unshETH and earn USH, with a multiplier 
///         based on how well the pool confirms to a target ratio of tokens
/// @dev    Uses Euclidean distance to calculate the "coordination ratio"

import "communal/Math.sol";
import "communal/SafeMath.sol";
import "communal/SafeERC20.sol";
import 'communal/TransferHelper.sol';
import "communal/ReentrancyGuard.sol";

// Inheritance
import "communal/Owned.sol";
import "forge-std/console.sol";


import { UD60x18, ud, fromUD60x18, unwrap, mulDiv18, add, sub, mul, div, mulDiv, inv, powu, exp } from "@prb/math/UD60x18.sol";

// just do everything in signed, the casting ugliness isn't worth the aids
// import { UD60x18, ud, fromUD60x18, mul, div, sqrt, inv, powu } from "@prb/math/UD60x18.sol";

interface ILSDRegistry {
    function vaultAddress() external view returns (address);
    //ratios should be in the form of [0.25e18, 0.25e18, 0.25e18, 0.25e18] for 4 LSDs
    function targetRatio() external view returns (uint256[] calldata);
    function lsdAddresses() external view returns (address[] calldata);
    function shanghaiTime() external view returns (uint256);
    function nonce() external view returns (uint256);
}

interface ILSDVault {
    function balanceInUnderlying() external view returns (uint256);
    function stakedETHperunshETH() external view returns (uint256);  
}
interface IDarknet {
    function checkPrice(address lsd) external view returns(uint256);
}

contract EuclideanFarm is Owned, ReentrancyGuard {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;


    /* ========== STATE VARIABLES ========== */

    // Instances
    IERC20 public stakingToken;
    
    // Constant for various precisions
    uint256 private constant MULTIPLIER_PRECISION = 1e18;

    // Time tracking
    uint256 public periodFinish;
    uint256 public lastUpdateTime;

    // Lock time and multiplier settings
    uint256 public lock_max_multiplier = uint256(3e18); // E18. 1x = e18
    uint256 public lock_time_for_max_multiplier; //set this to rewardsDuration - 6 hours at initialization
    uint256 public lock_time_min; //set this at initialization

    // Coordination multipliers
    uint256 public max_cord_multiplier = uint256(3e18);
    uint256 public min_cord_multiplier = uint256(1e18); 
    uint256 public nonce = 0;
    uint256 public max_nonce = 2; //no more than 2 changes to targetRatio
    // uint256 public lastRatioUpdate;
    // uint256 public min_cooldown = 21 days; 
    // uint256 public min_ratio_distance = 0.5e18;


    //there is only one lockTime - needs to be equal to shanghaiTime
    address public LSDRegistryAddress;
    address public LSDVaultAddress;
    uint256 public shanghaiTime;

    // Reward addresses, rates, and managers
    mapping(address => address) public rewardManagers; // token addr -> manager addr
    address[] public rewardTokens;
    uint256[] public rewardRates;
    string[] public rewardSymbols;
    mapping(address => uint256) public rewardTokenAddrToIdx; // token addr -> token index
    
    // Reward period
    uint256 public rewardsDuration; // from now until Shanghai
    
    // Reward tracking
    uint256[] private rewardsPerTokenStored;
    mapping(address => mapping(uint256 => uint256)) private userRewardsPerTokenPaid; // staker addr -> token id -> paid amount
    mapping(address => mapping(uint256 => uint256)) private rewards; // staker addr -> token id -> reward amount
    mapping(address => uint256) private lastRewardClaimTime; // staker addr -> timestamp

    // Balance tracking
    uint256 private _total_liquidity_locked;
    uint256 private _total_combined_weight;
    mapping(address => uint256) private _locked_liquidity;
    mapping(address => uint256) private _combined_weights;

    // Stake tracking
    mapping(address => LockedStake[]) private lockedStakes;

    // Greylisting of bad addresses
    mapping(address => bool) public greylist; //how long until this one is offensive too?

    // Administrative booleans
    bool public stakesUnlocked; // Release locked stakes in case of emergency
    bool public withdrawalsPaused; // For emergencies
    bool public rewardsCollectionPaused; // For emergencies
    bool public stakingPaused; // For emergencies

    //Price feed for LSDs for coordination multiplier calculations
    address public darknetAddress;

    /* ========== STRUCTS ========== */
    
    struct LockedStake {
        bytes32 kek_id;
        uint256 start_timestamp;
        uint256 liquidity;
        uint256 ending_timestamp;
        uint256 lock_multiplier; // 6 decimals of precision. 1x = 1000000
    }

    /* ========== MODIFIERS ========== */

    modifier onlyByOwner() {
        require(msg.sender == owner, "Not the owner");
        _;
    }

    modifier onlyTknMgrs(address reward_token_address) {
        require(msg.sender == owner || isTokenManagerFor(msg.sender, reward_token_address), "Not owner or tkn mgr");
        _;
    }

    modifier notStakingPaused() {
        require(stakingPaused == false, "Staking paused");
        _;
    }

    modifier updateRewardAndBalance(address account, bool sync_too) {
        _updateRewardAndBalance(account, sync_too);
        _;
    }
    
    /* ========== CONSTRUCTOR ========== */

    //this also needs to point to an LSDRegistry
    constructor (
        address _owner,
        address _stakingToken,
        address _LSDRegistry,
        uint256 _shanghaiTime,
        address _darknetAddress,
        string[] memory _rewardSymbols,
        address[] memory _rewardTokens,
        address[] memory _rewardManagers,
        uint256[] memory _rewardRates
    ) Owned(_owner){
        //check that LSDRegistry is not 0x0
        require(_LSDRegistry != address(0), "LSDRegistry is 0x0");
        LSDRegistryAddress = _LSDRegistry;
        LSDVaultAddress = ILSDRegistry(LSDRegistryAddress).vaultAddress();
        //check that LSDRegistry's shanghaiTime matches the given shanghaiTime
        require(_shanghaiTime == ILSDRegistry(LSDRegistryAddress).shanghaiTime(), "shanghaiTime mismatch");
        shanghaiTime = _shanghaiTime;
        stakingToken = IERC20(_stakingToken);
        darknetAddress = _darknetAddress;

        rewardTokens = _rewardTokens;
        rewardRates = _rewardRates;
        rewardSymbols = _rewardSymbols;
        rewardsDuration = shanghaiTime - block.timestamp;
        lock_time_for_max_multiplier = rewardsDuration - 24 hours;

        for (uint256 i = 0; i < _rewardTokens.length; i++){ 
            // For fast token address -> token ID lookups later
            rewardTokenAddrToIdx[_rewardTokens[i]] = i;

            // Initialize the stored rewards
            rewardsPerTokenStored.push(0);

            // Initialize the reward managers
            rewardManagers[_rewardTokens[i]] = _rewardManagers[i];
        }

        // Other booleans
        stakesUnlocked = false;

        // Initialization
        lastUpdateTime = block.timestamp;
        periodFinish = block.timestamp.add(rewardsDuration);
    }

    /* ========== VIEWS ========== */

    // Total locked liquidity tokens
    function totalLiquidityLocked() external view returns (uint256) {
        return _total_liquidity_locked;
    }

    // Locked liquidity for a given account
    function lockedLiquidityOf(address account) external view returns (uint256) {
        return _locked_liquidity[account];
    }

    // Total 'balance' used for calculating the percent of the pool the account owns
    // Takes into account the locked stake time multiplier
    function totalCombinedWeight() external view returns (uint256) {
        return _total_combined_weight;
    }

    // Combined weight for a specific account
    function combinedWeightOf(address account) external view returns (uint256) {
        return _combined_weights[account];
    }

    // Calculated the combined weight for an account
    function calcCurCombinedWeight(address account) public view
        returns (
            uint256 old_combined_weight,
            uint256 new_combined_weight
        )
    {
        // Get the old combined weight
        old_combined_weight = _combined_weights[account];

        // Loop through the locked stakes, first by getting the liquidity * lock_multiplier portion
        new_combined_weight = 0;
        for (uint256 i = 0; i < lockedStakes[account].length; i++) {
            LockedStake memory thisStake = lockedStakes[account][i];
            uint256 lock_multiplier = thisStake.lock_multiplier;
            //add coordination multiplier here
            uint256 cord_multiplier = coordinationMultiplier();
            require(cord_multiplier != 0, "Multiplier error");
            //set min_cord_multiplier < 1e18 if we want to shrink yield below base rate
            if (cord_multiplier <= min_cord_multiplier){
                cord_multiplier = min_cord_multiplier;
            }

            // If the lock is expired
            if (thisStake.ending_timestamp <= block.timestamp) {
                // If the lock expired in the time since the last claim, the weight needs to be proportionately averaged this time
                if (lastRewardClaimTime[account] < thisStake.ending_timestamp){
                    uint256 time_before_expiry = (thisStake.ending_timestamp).sub(lastRewardClaimTime[account]);
                    uint256 time_after_expiry = (block.timestamp).sub(thisStake.ending_timestamp);

                    // Get the weighted-average lock_multiplier
                    uint256 numerator = ((lock_multiplier).mul(time_before_expiry)).add(((MULTIPLIER_PRECISION).mul(time_after_expiry)));
                    lock_multiplier = numerator.div(time_before_expiry.add(time_after_expiry));
                }
                // Otherwise, it needs to just be 1x
                else {
                    lock_multiplier = MULTIPLIER_PRECISION;
                }
            }

            uint256 liquidity = thisStake.liquidity;
            uint256 combined_boosted_amount = liquidity.mul(lock_multiplier).div(MULTIPLIER_PRECISION);
            uint256 coordination_boosted_amount = combined_boosted_amount.mul(cord_multiplier).div(MULTIPLIER_PRECISION);
            new_combined_weight = new_combined_weight.add(coordination_boosted_amount);
        }
    }

    // All the locked stakes for a given account
    function lockedStakesOf(address account) external view returns (LockedStake[] memory) {
        return lockedStakes[account];
    }

    // All the locked stakes for a given account
    function getRewardSymbols() external view returns (string[] memory) {
        return rewardSymbols;
    }

    // All the reward tokens
    function getAllRewardTokens() external view returns (address[] memory) {
        return rewardTokens;
    }

    // All the reward rates
    function getAllRewardRates() external view returns (uint256[] memory) {
        return rewardRates;
    }
    
    // Multiplier amount, given the length of the lock
    function lockMultiplier(uint256 secs) public view returns (uint256) {
        uint256 lock_multiplier =
            uint256(MULTIPLIER_PRECISION).add(
                secs
                    .mul(lock_max_multiplier.sub(MULTIPLIER_PRECISION))
                    .div(lock_time_for_max_multiplier)
            );
        if (lock_multiplier > lock_max_multiplier) lock_multiplier = lock_max_multiplier;
        return lock_multiplier;
    }

    function sqrt(uint y) internal pure returns (uint z) {
        if (y > 3) {
            z = y;
            uint x = y / 2 + 1;
            while (x < z) {
                z = x;
                x = (y / x + x) / 2;
            }
        } else if (y != 0) {
            z = 1;
        }
        // else z = 0 (default value)
    }
   
    function euclideanDistance(uint256[] memory _a, uint256[] memory _b) internal pure returns (uint256) {
            require(_a.length == _b.length, "Array length mismatch");
            int256 a;
            int256 b;
            uint256 sumSqDiff;
            uint256 diff;
            for (uint256 i = 0; i < _a.length; i++) {
                a = int256(_a[i]/1e15);
                b = int256(_b[i]/1e15);
                diff = uint256(a > b ? a - b : b - a);
                uint256 squareDiff = diff**2;
                sumSqDiff += squareDiff;
            }
            return sqrt(sumSqDiff)*1e15;
    }

    function coordinationMultiplier() public view returns(uint256) {
        //get ratios
        //fetch the current targetRatio locally
        //ratios should be in the form of [0.25e18, 0.25e18, 0.25e18, 0.25e18] for 4 LSDs
        uint256[] memory targetRatio = ILSDRegistry(LSDRegistryAddress).targetRatio();
        address[] memory lsdAddresses = ILSDRegistry(LSDRegistryAddress).lsdAddresses();
        //make sure the lengths match
        require(targetRatio.length == lsdAddresses.length, "targetRatio and lsdAddresses length mismatch");
        uint256 tabs = lsdAddresses.length;
        console.log(tabs);
        uint256[] memory currentRatio = new uint256[](tabs);
        console.log(currentRatio.length);
        console.log(LSDVaultAddress);
        uint256 totalETHbalance = ILSDVault(LSDVaultAddress).balanceInUnderlying();
        console.log(totalETHbalance);
        //get the current balances of all LSDs in vault in terms of underlying ETH to compute ratio
        for (uint256 i = 0; i < tabs; i++) {
            uint256 balance = IERC20(lsdAddresses[i]).balanceOf(LSDVaultAddress);
            //convert to actual underlying amounts
            uint256 rate = IDarknet(darknetAddress).checkPrice(lsdAddresses[i]);
            uint256 ratio = mulDiv(balance, rate, totalETHbalance);
            currentRatio[i] = ratio;
        }
        //from here onwards these operations cost ~50k gas 
        uint256 _x = euclideanDistance(targetRatio, currentRatio);
        uint256 L = mulDiv18(_x, 2.5e18);
        UD60x18 l_scaled = div(ud(L), ud(1.0e18));
        UD60x18 e_L = exp(l_scaled);
        UD60x18 hell = ud(3.0e18).sub(inv(e_L)).sub(ud(L));
        UD60x18 hella = div(powu(hell, 3),ud(4.0e18));
        return unwrap(hella.add(ud(1.0e18)));
    }

    // Last time the reward was applicable
    function lastTimeRewardApplicable() internal view returns (uint256) {
        return Math.min(block.timestamp, periodFinish);
    }

    // Amount of reward tokens per LP token
    function rewardsPerToken() public view returns (uint256[] memory newRewardsPerTokenStored) {
        if (_total_liquidity_locked == 0 || _total_combined_weight == 0) {
            return rewardsPerTokenStored;
        }
        else {
            newRewardsPerTokenStored = new uint256[](rewardTokens.length);
            for (uint256 i = 0; i < rewardsPerTokenStored.length; i++){ 
                newRewardsPerTokenStored[i] = rewardsPerTokenStored[i].add(
                    lastTimeRewardApplicable().sub(lastUpdateTime).mul(rewardRates[i]).mul(1e18).div(_total_combined_weight)
                );
            }
            return newRewardsPerTokenStored;
        }
    }

    // Amount of reward tokens an account has earned / accrued
    // Note: In the edge-case of one of the account's stake expiring since the last claim, this will
    // return a slightly inflated number
    function earned(address account) public view returns (uint256[] memory new_earned) {
        uint256[] memory reward_arr = rewardsPerToken();
        new_earned = new uint256[](rewardTokens.length);

        if (_combined_weights[account] == 0){
            for (uint256 i = 0; i < rewardTokens.length; i++){ 
                new_earned[i] = 0;
            }
        }
        else {
            for (uint256 i = 0; i < rewardTokens.length; i++){ 
                new_earned[i] = (_combined_weights[account])
                    .mul(reward_arr[i].sub(userRewardsPerTokenPaid[account][i]))
                    .div(1e18)
                    .add(rewards[account][i]);
            }
        }
    }

    // Total reward tokens emitted in the given period
    function getRewardForDuration() external view returns (uint256[] memory rewards_per_duration_arr) {
        rewards_per_duration_arr = new uint256[](rewardRates.length);

        for (uint256 i = 0; i < rewardRates.length; i++){ 
            rewards_per_duration_arr[i] = rewardRates[i].mul(rewardsDuration);
        }
    }

    // See if the caller_addr is a manager for the reward token 
    function isTokenManagerFor(address caller_addr, address reward_token_addr) public view returns (bool){
        if (caller_addr == owner) return true; // Contract owner
        else if (rewardManagers[reward_token_addr] == caller_addr) return true; // Reward manager
        return false; 
    }

    /* ========== MUTATIVE FUNCTIONS ========== */
    function synchronize() external {
        uint256 proposedNonce = ILSDRegistry(LSDRegistryAddress).nonce();
        require(nonce != proposedNonce, "Already synchronized");
         _synchronize();
    }

    function _synchronize() internal {
        //set current coordination-boosted rate to the new min
        uint256 current_boosted_rate = coordinationMultiplier()*rewardRates[0]/1e18; //only for USH rewards, change later if needed
        rewardRates[0] = current_boosted_rate;
        //update to the new target ratio
    }

    function _updateRewardAndBalance(address account, bool sync_too) internal {
        // Need to retro-adjust some things if the period hasn't been renewed, then start a new one
        if (sync_too){
            sync();
        }
        
        if (account != address(0)) {
            // To keep the math correct, the user's combined weight must be recomputed
            (   
                uint256 old_combined_weight,
                uint256 new_combined_weight
            ) = calcCurCombinedWeight(account);

            // Calculate the earnings first
            _syncEarned(account);

            // Update the user's and the global combined weights
            if (new_combined_weight >= old_combined_weight) {
                uint256 weight_diff = new_combined_weight.sub(old_combined_weight);
                _total_combined_weight = _total_combined_weight.add(weight_diff);
                _combined_weights[account] = old_combined_weight.add(weight_diff);
            } else {
                uint256 weight_diff = old_combined_weight.sub(new_combined_weight);
                _total_combined_weight = _total_combined_weight.sub(weight_diff);
                _combined_weights[account] = old_combined_weight.sub(weight_diff);
            }

        }
    }

    function _syncEarned(address account) internal {
        if (account != address(0)) {
            // Calculate the earnings
            uint256[] memory earned_arr = earned(account);

            // Update the rewards array
            for (uint256 i = 0; i < earned_arr.length; i++){ 
                rewards[account][i] = earned_arr[i];
            }

            // Update the rewards paid array
            for (uint256 i = 0; i < earned_arr.length; i++){ 
                userRewardsPerTokenPaid[account][i] = rewardsPerTokenStored[i];
            }
        }
    }

    // Two different stake functions are needed because of delegateCall and msg.sender issues
    function stakeLocked(uint256 liquidity) nonReentrant public {

        _stakeLocked(msg.sender, msg.sender, liquidity, block.timestamp);
    }

    // If this were not internal, and source_address had an infinite approve, this could be exploitable
    // (pull funds from source_address and stake for an arbitrary staker_address)
    function _stakeLocked(
        address staker_address, 
        address source_address, 
        uint256 liquidity, 
        uint256 start_timestamp
    ) internal updateRewardAndBalance(staker_address, true) {
        require(!stakingPaused, "Staking paused");
        require(liquidity > 0, "Must stake more than zero");
        require(greylist[staker_address] == false, "Address has been greylisted");
        // require(secs >= lock_time_min, "Minimum stake time not met");
        // require(secs <= lock_time_for_max_multiplier,"Trying to lock for too long");
        uint256 secs = shanghaiTime - block.timestamp;
        uint256 lock_multiplier = lockMultiplier(secs);
        bytes32 kek_id = keccak256(abi.encodePacked(staker_address, start_timestamp, liquidity, _locked_liquidity[staker_address]));
        lockedStakes[staker_address].push(LockedStake(
            kek_id,
            start_timestamp,
            liquidity,
            shanghaiTime,//replaced start_timestamp.add(secs) w/ shanghaiTime
            lock_multiplier
        ));

        // Pull the tokens from the source_address
        TransferHelper.safeTransferFrom(address(stakingToken), source_address, address(this), liquidity);

        // Update liquidities
        _total_liquidity_locked = _total_liquidity_locked.add(liquidity);
        _locked_liquidity[staker_address] = _locked_liquidity[staker_address].add(liquidity);

        // Need to call to update the combined weights
        _updateRewardAndBalance(staker_address, false);

        // Needed for edge case if the staker only claims once, and after the lock expired
        if (lastRewardClaimTime[staker_address] == 0) lastRewardClaimTime[staker_address] = block.timestamp;

        emit StakeLocked(staker_address, liquidity, secs, kek_id, source_address);
    }

    // Two different withdrawLocked functions are needed because of delegateCall and msg.sender issues
    function withdrawLocked(bytes32 kek_id) nonReentrant public {
        require(withdrawalsPaused == false, "Withdrawals paused");
        _withdrawLocked(msg.sender, msg.sender, kek_id);
    }

    // No withdrawer == msg.sender check needed since this is only internally callable and the checks are done in the wrapper
    // functions like withdraw()
    function _withdrawLocked(address staker_address, address destination_address, bytes32 kek_id) internal  {
        // Collect rewards first and then update the balances
        _getReward(staker_address, destination_address);

        LockedStake memory thisStake;
        thisStake.liquidity = 0;
        uint theArrayIndex;
        for (uint256 i = 0; i < lockedStakes[staker_address].length; i++){ 
            if (kek_id == lockedStakes[staker_address][i].kek_id){
                thisStake = lockedStakes[staker_address][i];
                theArrayIndex = i;
                break;
            }
        }
        require(thisStake.kek_id == kek_id, "Stake not found");
        require(block.timestamp >= thisStake.ending_timestamp || stakesUnlocked == true, "Stake is still locked!");

        uint256 liquidity = thisStake.liquidity;

        if (liquidity > 0) {
            // Update liquidities
            _total_liquidity_locked = _total_liquidity_locked.sub(liquidity);
            _locked_liquidity[staker_address] = _locked_liquidity[staker_address].sub(liquidity);

            // Remove the stake from the array
            delete lockedStakes[staker_address][theArrayIndex];

            // Need to call to update the combined weights
            _updateRewardAndBalance(staker_address, false);

            // Give the tokens to the destination_address
            // Should throw if insufficient balance
            stakingToken.transfer(destination_address, liquidity);

            emit WithdrawLocked(staker_address, liquidity, kek_id, destination_address);
        }

    }
    
    // Two different getReward functions are needed because of delegateCall and msg.sender issues
    function getReward() external nonReentrant returns (uint256[] memory) {
        require(rewardsCollectionPaused == false,"Rewards collection paused");
        return _getReward(msg.sender, msg.sender);
    }

    // No withdrawer == msg.sender check needed since this is only internally callable
    function _getReward(address rewardee, address destination_address) internal updateRewardAndBalance(rewardee, true) returns (uint256[] memory rewards_before) {
        // Update the rewards array and distribute rewards
        rewards_before = new uint256[](rewardTokens.length);

        for (uint256 i = 0; i < rewardTokens.length; i++){ 
            rewards_before[i] = rewards[rewardee][i];
            rewards[rewardee][i] = 0;
            //use SafeERC20.transfer
            IERC20(rewardTokens[i]).transfer(destination_address, rewards_before[i]);
            emit RewardPaid(rewardee, rewards_before[i], rewardTokens[i], destination_address);
        }

        lastRewardClaimTime[rewardee] = block.timestamp;
    }

    // If the period expired, DON'T renew it
    function retroCatchUp() internal {
        // Failsafe check
        require(block.timestamp > periodFinish, "Period has not expired yet!");

        // Ensure the provided reward amount is not more than the balance in the contract.
        // This keeps the reward rate in the right range, preventing overflows due to
        // very high values of rewardRate in the earned and rewardsPerToken functions;
        // Reward + leftover must be less than 2^256 / 10^18 to avoid overflow.
        // uint256 num_periods_elapsed = uint256(block.timestamp.sub(periodFinish)) / rewardsDuration; // Floor division to the nearest period
        
        // // Make sure there are enough tokens to renew the reward period
        // for (uint256 i = 0; i < rewardTokens.length; i++){ 
        //     require(rewardRates[i].mul(rewardsDuration).mul(num_periods_elapsed + 1) <= IERC20(rewardTokens[i]).balanceOf(address(this)), string(abi.encodePacked("Not enough reward tokens available: ", rewardTokens[i])) );
        // }
        
        // uint256 old_lastUpdateTime = lastUpdateTime;
        // uint256 new_lastUpdateTime = block.timestamp;

        // lastUpdateTime = periodFinish;
        //periodFinish = periodFinish.add((num_periods_elapsed.add(1)).mul(rewardsDuration));

        _updateStoredRewardsAndTime();

        //emit RewardsPeriodRenewed(address(stakingToken));
    }

    function _updateStoredRewardsAndTime() internal {
        // Get the rewards
        uint256[] memory rewards_per_token = rewardsPerToken();

        // Update the rewardsPerTokenStored
        for (uint256 i = 0; i < rewardsPerTokenStored.length; i++){ 
            rewardsPerTokenStored[i] = rewards_per_token[i];
        }

        // Update the last stored time
        lastUpdateTime = lastTimeRewardApplicable();
    }

    function sync() public {
        if (block.timestamp > periodFinish) {
            retroCatchUp();
        }
        else {
            _updateStoredRewardsAndTime();
        }
    }

    /* ========== RESTRICTED FUNCTIONS ========== */

    // Added to support recovering LP Rewards and other mistaken tokens from other systems to be distributed to holders
    function recoverERC20(address tokenAddress, uint256 tokenAmount) external onlyTknMgrs(tokenAddress) {
        // Cannot rug the staking / LP tokens
        require(tokenAddress != address(stakingToken), "Cannot rug staking / LP tokens");

        // Check if the desired token is a reward token
        bool isRewardToken = false;
        for (uint256 i = 0; i < rewardTokens.length; i++){ 
            if (rewardTokens[i] == tokenAddress) {
                isRewardToken = true;
                break;
            }
        }

        // Only the reward managers can take back their reward tokens
        if (isRewardToken && rewardManagers[tokenAddress] == msg.sender){
            IERC20(tokenAddress).transfer(msg.sender, tokenAmount);
            emit Recovered(msg.sender, tokenAddress, tokenAmount);
            return;
        }

        // Other tokens, like airdrops or accidental deposits, can be withdrawn by the owner
        else if (!isRewardToken && (msg.sender == owner)){
            IERC20(tokenAddress).transfer(msg.sender, tokenAmount);
            emit Recovered(msg.sender, tokenAddress, tokenAmount);
            return;
        }

        // If none of the above conditions are true
        else {
            revert("No valid tokens to recover");
        }
    }

    function setRewardsDuration(uint256 _rewardsDuration) external onlyByOwner {
        require(_rewardsDuration >= 86400, "Rewards duration too short");
        require(
            periodFinish == 0 || block.timestamp > periodFinish,
            "Reward period incomplete"
        );
        rewardsDuration = _rewardsDuration;
        emit RewardsDurationUpdated(rewardsDuration);
    }

    function setMultipliers(uint256 _lock_max_multiplier) external onlyByOwner {
        require(_lock_max_multiplier >= uint256(1e18), "Multiplier must be greater than or equal to 1e18");
        lock_max_multiplier = _lock_max_multiplier;
        emit LockedStakeMaxMultiplierUpdated(lock_max_multiplier);
    }

    function setLockedStakeTimeForMinAndMaxMultiplier(uint256 _lock_time_for_max_multiplier, uint256 _lock_time_min) external onlyByOwner {
        require(_lock_time_for_max_multiplier >= 1, "Mul max time must be >= 1");
        require(_lock_time_min >= 1, "Mul min time must be >= 1");

        lock_time_for_max_multiplier = _lock_time_for_max_multiplier;
        lock_time_min = _lock_time_min;

        emit LockedStakeTimeForMaxMultiplier(lock_time_for_max_multiplier);
        emit LockedStakeMinTime(_lock_time_min);
    }

    function greylistAddress(address _address) external onlyByOwner {
        greylist[_address] = !(greylist[_address]);
    }

    function unlockStakes() external onlyByOwner {
        stakesUnlocked = !stakesUnlocked;
    }

    function toggleStaking() external onlyByOwner {
        stakingPaused = !stakingPaused;
    }

    function toggleWithdrawals() external onlyByOwner {
        withdrawalsPaused = !withdrawalsPaused;
    }

    function toggleRewardsCollection() external onlyByOwner {
        rewardsCollectionPaused = !rewardsCollectionPaused;
    }

    // The owner or the reward token managers can set reward rates 
    function setRewardRate(address reward_token_address, uint256 new_rate, bool sync_too) external onlyTknMgrs(reward_token_address) {
        rewardRates[rewardTokenAddrToIdx[reward_token_address]] = new_rate;
        
        if (sync_too){
            sync();
        }
    }

    // The owner or the reward token managers can change managers
    function changeTokenManager(address reward_token_address, address new_manager_address) external onlyTknMgrs(reward_token_address) {
        rewardManagers[reward_token_address] = new_manager_address;
    }

    /* ========== EVENTS ========== */

    event StakeLocked(address indexed user, uint256 amount, uint256 secs, bytes32 kek_id, address source_address);
    event WithdrawLocked(address indexed user, uint256 amount, bytes32 kek_id, address destination_address);
    event RewardPaid(address indexed user, uint256 reward, address token_address, address destination_address);
    event RewardsDurationUpdated(uint256 newDuration);
    event Recovered(address destination_address, address token, uint256 amount);
    event RewardsPeriodRenewed(address token);
    event LockedStakeMaxMultiplierUpdated(uint256 multiplier);
    event LockedStakeTimeForMaxMultiplier(uint256 secs);
    event LockedStakeMinTime(uint256 secs);
}