// SPDX-License-Identifier: UNLICENSED

// File: @openzeppelin/contracts/utils/Address.sol


// 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);
            }
        }
    }
}

// File: @openzeppelin/contracts/token/ERC20/extensions/draft-IERC20Permit.sol


// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);

    /**
     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol


// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);

    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) external returns (bool);
}

// File: @openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol


// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;




/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using Address for address;

    function safeTransfer(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(
        IERC20 token,
        address from,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
    }

    function safePermit(
        IERC20Permit token,
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        uint256 nonceBefore = token.nonces(owner);
        token.permit(owner, spender, value, deadline, v, r, s);
        uint256 nonceAfter = token.nonces(owner);
        require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) {
            // Return data is optional
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}

// File: src/interfaces/IWETH.sol

// contracts/Bridge.sol


pragma solidity ^0.8.0;


interface IWETH is IERC20 {
    function deposit() external payable;
    function withdraw(uint amount) external;
}
// File: src/libraries/external/BytesLib.sol


/*
 * @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;
    }
}

// File: src/contracts/HubSpokeStructs.sol


pragma solidity ^0.8.0;

contract HubSpokeStructs {
    struct VaultAmount {
        uint256 deposited;
        uint256 borrowed;
    }

    struct AccrualIndices {
        uint256 deposited;
        uint256 borrowed;
    }

    struct AssetInfo {
        uint256 collateralizationRatioDeposit;
        uint256 collateralizationRatioBorrow;
        bytes32 pythId;
        // pyth id info
        uint8 decimals;
        PiecewiseInterestRateModel interestRateModel;
        bool exists;
    }

    struct InterestRateModel {
        uint64 ratePrecision;
        uint64 rateIntercept;
        uint64 rateCoefficientA;
        uint256 reserveFactor;
        uint256 reservePrecision;
    }

    struct PiecewiseInterestRateModel {
        uint64 ratePrecision;
        uint256[] kinks;
        uint256[] rates;
        uint256 reserveFactor;
        uint256 reservePrecision;
    }

    enum Action {
        Deposit,
        Borrow,
        Withdraw,
        Repay,
        DepositNative,
        RepayNative
    }

    enum Round {
        UP,
        DOWN
    }

    struct ActionPayload {
        Action action;
        address sender;
        address assetAddress;
        uint256 assetAmount;
    }

    // struct for mock oracle price
    struct Price {
        int64 price;
        uint64 conf;
        int32 expo;
        uint256 publishTime;
    }
}

// File: src/contracts/HubSpokeMessages.sol


pragma solidity ^0.8.0;



contract HubSpokeMessages is HubSpokeStructs {
    using BytesLib for bytes;

    function encodeActionPayload(ActionPayload memory payload) internal pure returns (bytes memory) {
        return abi.encodePacked(uint8(payload.action), payload.sender, payload.assetAddress, payload.assetAmount);
    }

    function decodeActionPayload(bytes memory serialized) internal pure returns (ActionPayload memory params) {
        uint256 index = 0;

        params.action = Action(serialized.toUint8(index));
        index += 1;

        params.sender = serialized.toAddress(index);
        index += 20;

        params.assetAddress = serialized.toAddress(index);
        index += 20;

        params.assetAmount = serialized.toUint256(index);
    }
}

// File: src/contracts/lendingSpoke/SpokeState.sol


pragma solidity ^0.8.0;


contract SpokeStorage is HubSpokeStructs {
    struct Provider {
        uint16 chainId;
        address payable wormhole;
        address tokenBridge;
    }

    struct State {
        Provider provider;
        // number of confirmations for wormhole messages
        uint8 consistencyLevel;
        uint16 hubChainId;
        address hubContractAddress;
        // @dev storage gap
        uint256[50] ______gap;
    }
}

contract SpokeState {
    SpokeStorage.State _state;
}

// File: src/contracts/lendingSpoke/SpokeSetters.sol


pragma solidity ^0.8.0;



contract SpokeSetters is HubSpokeStructs, SpokeState {
    function setChainId(uint16 chainId) internal {
        _state.provider.chainId = chainId;
    }

    function setWormhole(address wormholeAddress) internal {
        _state.provider.wormhole = payable(wormholeAddress);
    }

    function setTokenBridge(address tokenBridgeAddress) internal {
        _state.provider.tokenBridge = tokenBridgeAddress;
    }

    function setHubChainId(uint16 hubChainId) internal {
        _state.hubChainId = hubChainId;
    }

    function setHubContractAddress(address hubContractAddress) internal {
        _state.hubContractAddress = hubContractAddress;
    }
}

// File: src/interfaces/IWormhole.sol

// contracts/Messages.sol


pragma solidity ^0.8.0;

interface IWormhole {
    struct Signature {
        bytes32 r;
        bytes32 s;
        uint8 v;
        uint8 guardianIndex;
    }

    struct VM {
        uint8 version;
        uint32 timestamp;
        uint32 nonce;
        uint16 emitterChainId;
        bytes32 emitterAddress;
        uint64 sequence;
        uint8 consistencyLevel;
        bytes payload;
        uint32 guardianSetIndex;
        Signature[] signatures;
        bytes32 hash;
    }

    struct WormholeBodyParams {
        uint32 timestamp;
        uint32 nonce;
        uint16 emitterChainId;
        bytes32 emitterAddress;
        uint64 sequence;
        uint8 consistencyLevel;
    }

    event LogMessagePublished(
        address indexed sender, uint64 sequence, uint32 nonce, bytes payload, uint8 consistencyLevel
    );

    function publishMessage(uint32 nonce, bytes memory payload, uint8 consistencyLevel)
        external
        payable
        returns (uint64 sequence);

    function parseAndVerifyVM(bytes calldata encodedVM)
        external
        view
        returns (VM memory vm, bool valid, string memory reason);

    function chainId() external view returns (uint16);

    function messageFee() external view returns (uint256);

    // added due to WormholeSimulator need
    function getCurrentGuardianSetIndex() external view returns (uint32);

    struct GuardianSet {
        address[] keys;
        uint32 expirationTime;
    }

    function getGuardianSet(uint32 guardianSetIndex) external view returns (GuardianSet memory guardians);

    function parseVM(bytes memory encodedVM) external pure returns (VM memory vm);
}

// File: src/interfaces/ITokenBridge.sol

// contracts/Bridge.sol


pragma solidity ^0.8.0;



interface ITokenBridge {
    struct Transfer {
        uint8 payloadID;
        uint256 amount;
        bytes32 tokenAddress;
        uint16 tokenChain;
        bytes32 to;
        uint16 toChain;
        uint256 fee;
    }

    struct TransferWithPayload {
        uint8 payloadID;
        uint256 amount;
        bytes32 tokenAddress;
        uint16 tokenChain;
        bytes32 to;
        uint16 toChain;
        bytes32 fromAddress;
        bytes payload;
    }

    struct AssetMeta {
        uint8 payloadID;
        bytes32 tokenAddress;
        uint16 tokenChain;
        uint8 decimals;
        bytes32 symbol;
        bytes32 name;
    }

    struct RegisterChain {
        bytes32 module;
        uint8 action;
        uint16 chainId;

        uint16 emitterChainID;
        bytes32 emitterAddress;
    }

     struct UpgradeContract {
        bytes32 module;
        uint8 action;
        uint16 chainId;

        bytes32 newContract;
    }

    struct RecoverChainId {
        bytes32 module;
        uint8 action;

        uint256 evmChainId;
        uint16 newChainId;
    }

    event ContractUpgraded(address indexed oldContract, address indexed newContract);

    function _parseTransferCommon(bytes memory encoded) external pure returns (Transfer memory transfer);

    function attestToken(address tokenAddress, uint32 nonce) external payable returns (uint64 sequence);

    function wrapAndTransferETH(uint16 recipientChain, bytes32 recipient, uint256 arbiterFee, uint32 nonce) external payable returns (uint64 sequence);

    function wrapAndTransferETHWithPayload(uint16 recipientChain, bytes32 recipient, uint32 nonce, bytes memory payload) external payable returns (uint64 sequence);

    function transferTokens(address token, uint256 amount, uint16 recipientChain, bytes32 recipient, uint256 arbiterFee, uint32 nonce) external payable returns (uint64 sequence);

    function transferTokensWithPayload(address token, uint256 amount, uint16 recipientChain, bytes32 recipient, uint32 nonce, bytes memory payload) external payable returns (uint64 sequence);

    function updateWrapped(bytes memory encodedVm) external returns (address token);

    function createWrapped(bytes memory encodedVm) external returns (address token);

    function completeTransferWithPayload(bytes memory encodedVm) external returns (bytes memory);

    function completeTransferAndUnwrapETHWithPayload(bytes memory encodedVm) external returns (bytes memory);

    function completeTransfer(bytes memory encodedVm) external;

    function completeTransferAndUnwrapETH(bytes memory encodedVm) external;

    function encodeAssetMeta(AssetMeta memory meta) external pure returns (bytes memory encoded);

    function encodeTransfer(Transfer memory transfer) external pure returns (bytes memory encoded);

    function encodeTransferWithPayload(TransferWithPayload memory transfer) external pure returns (bytes memory encoded);

    function parsePayloadID(bytes memory encoded) external pure returns (uint8 payloadID);

    function parseAssetMeta(bytes memory encoded) external pure returns (AssetMeta memory meta);

    function parseTransfer(bytes memory encoded) external pure returns (Transfer memory transfer);

    function parseTransferWithPayload(bytes memory encoded) external pure returns (TransferWithPayload memory transfer);

    function governanceActionIsConsumed(bytes32 hash) external view returns (bool);

    function isInitialized(address impl) external view returns (bool);

    function isTransferCompleted(bytes32 hash) external view returns (bool);

    function wormhole() external view returns (IWormhole);

    function chainId() external view returns (uint16);

    function evmChainId() external view returns (uint256);

    function isFork() external view returns (bool);

    function governanceChainId() external view returns (uint16);

    function governanceContract() external view returns (bytes32);

    function wrappedAsset(uint16 tokenChainId, bytes32 tokenAddress) external view returns (address);

    function bridgeContracts(uint16 chainId_) external view returns (bytes32);

    function tokenImplementation() external view returns (address);

    function WETH() external view returns (IWETH);

    function outstandingBridged(address token) external view returns (uint256);

    function isWrappedAsset(address token) external view returns (bool);

    function finality() external view returns (uint8);

    function implementation() external view returns (address);

    function initialize() external;

    function registerChain(bytes memory encodedVM) external;

    function upgrade(bytes memory encodedVM) external;

    function submitRecoverChainId(bytes memory encodedVM) external;

    function parseRegisterChain(bytes memory encoded) external pure returns (RegisterChain memory chain);

    function parseUpgrade(bytes memory encoded) external pure returns (UpgradeContract memory chain);

    function parseRecoverChainId(bytes memory encodedRecoverChainId) external pure returns (RecoverChainId memory rci);
}
// File: src/contracts/lendingSpoke/SpokeGetters.sol


pragma solidity ^0.8.0;





contract SpokeGetters is HubSpokeStructs, SpokeState {
    function chainId() public view returns (uint16) {
        return _state.provider.chainId;
    }

    function wormhole() internal view returns (IWormhole) {
        return IWormhole(_state.provider.wormhole);
    }

    function tokenBridge() public view returns (ITokenBridge) {
        return ITokenBridge(payable(_state.provider.tokenBridge));
    }

    function tokenBridgeAddress() public view returns (address) {
        return _state.provider.tokenBridge;
    }

    function consistencyLevel() internal view returns (uint8) {
        return _state.consistencyLevel;
    }

    function hubChainId() internal view returns (uint16) {
        return _state.hubChainId;
    }

    function hubContractAddress() internal view returns (address) {
        return _state.hubContractAddress;
    }
}

// File: src/contracts/lendingSpoke/SpokeUtilities.sol


pragma solidity ^0.8.0;







contract SpokeUtilities is HubSpokeStructs, SpokeState, SpokeGetters, SpokeSetters {
    function sendWormholeMessage(bytes memory payload) internal returns (uint64 sequence) {
        sequence = wormhole().publishMessage(
            0, // nonce
            payload,
            consistencyLevel()
        );
    }

    function sendTokenBridgeMessage(address assetAddress, uint256 assetAmount, bytes memory payload)
        internal
        returns (uint64 sequence)
    {
        SafeERC20.safeTransferFrom(IERC20(assetAddress), msg.sender, address(this), assetAmount);

        SafeERC20.safeApprove(IERC20(assetAddress), tokenBridgeAddress(), assetAmount);

        sequence = tokenBridge().transferTokensWithPayload(
            assetAddress, assetAmount, hubChainId(), bytes32(uint256(uint160(hubContractAddress()))), 0, payload
        );
    }

    function sendTokenBridgeMessageNative(uint256 amount, bytes memory payload) internal returns (uint64 sequence) {
        sequence = tokenBridge().wrapAndTransferETHWithPayload{value: amount}(
            hubChainId(), bytes32(uint256(uint160(hubContractAddress()))), 0, payload
        );
    }

    function requireAssetAmountValidForTokenBridge(address assetAddress, uint256 assetAmount) internal view {
        (, bytes memory queriedDecimals) = assetAddress.staticcall(abi.encodeWithSignature("decimals()"));
        uint8 decimals = abi.decode(queriedDecimals, (uint8));
        require(
            deNormalizeAmount(normalizeAmount(assetAmount, decimals), decimals) == assetAmount,
            "Too many decimal places"
        );
    }

    function normalizeAmount(uint256 amount, uint8 decimals) internal pure returns (uint256) {
        if (decimals > 8) {
            amount /= 10 ** (decimals - 8);
        }
        return amount;
    }

    function deNormalizeAmount(uint256 amount, uint8 decimals) internal pure returns (uint256) {
        if (decimals > 8) {
            amount *= 10 ** (decimals - 8);
        }
        return amount;
    }
}

// File: src/contracts/lendingSpoke/Spoke.sol


pragma solidity ^0.8.0;







contract Spoke is HubSpokeStructs, HubSpokeMessages, SpokeGetters, SpokeSetters, SpokeUtilities {
    /**
     * @notice Spoke constructor - Initializes a new spoke with given parameters
     * 
     * @param chainId: Chain ID of the chain that this Spoke is deployed on
     * @param wormhole: Address of the Wormhole contract on this Spoke chain
     * @param tokenBridge: Address of the TokenBridge contract on this Spoke chain
     * @param hubChainId: Chain ID of the Hub
     * @param hubContractAddress: Contract address of the Hub contract (on the Hub chain)
     */
    constructor(
        uint16 chainId,
        address wormhole,
        address tokenBridge,
        uint16 hubChainId,
        address hubContractAddress
    ) {
        setChainId(chainId);
        setWormhole(wormhole);
        setTokenBridge(tokenBridge);
        setHubChainId(hubChainId);
        setHubContractAddress(hubContractAddress);
    }

    function depositCollateral(address assetAddress, uint256 assetAmount) public returns (uint64 sequence) {
        sequence = doAction(Action.Deposit, assetAddress, assetAmount);
    }

    function withdrawCollateral(address assetAddress, uint256 assetAmount) public returns (uint64 sequence) {
        sequence = doAction(Action.Withdraw, assetAddress, assetAmount);
    }

    function borrow(address assetAddress, uint256 assetAmount) public returns (uint64 sequence) {
        sequence = doAction(Action.Borrow, assetAddress, assetAmount);
    }

    function repay(address assetAddress, uint256 assetAmount) public returns (uint64 sequence) {
        sequence = doAction(Action.Repay, assetAddress, assetAmount);
    }

    function depositCollateralNative() public payable returns (uint64 sequence) {
        sequence = doAction(Action.DepositNative, address(tokenBridge().WETH()), msg.value - wormhole().messageFee());
    }

    function repayNative() public payable returns (uint64 sequence) {
        sequence = doAction(Action.RepayNative, address(tokenBridge().WETH()), msg.value - wormhole().messageFee());
    }

    /**
     * @notice Initiates an action (deposit, borrow, withdraw, or repay) on the spoke by sending a Wormhole message (potentially a TokenBridge message with tokens) to the Hub
     * 
     * @param action - the action (either Deposit, Borrow, Withdraw, or Repay)
     * @param assetAddress - the address of the relevant asset
     * @param assetAmount - the amount of the asset assetAddress
     */
    function doAction(Action action, address assetAddress, uint256 assetAmount) internal returns (uint64 sequence) {
        requireAssetAmountValidForTokenBridge(assetAddress, assetAmount);
        Action hubAction = action;
        if (action == Action.DepositNative) {
            hubAction = Action.Deposit;
        }
        if (action == Action.RepayNative) {
            hubAction = Action.Repay;
        }

        ActionPayload memory payload =
            ActionPayload({action: hubAction, sender: msg.sender, assetAddress: assetAddress, assetAmount: assetAmount});

        bytes memory serialized = encodeActionPayload(payload);

        if (action == Action.Deposit || action == Action.Repay) {
            sequence = sendTokenBridgeMessage(assetAddress, assetAmount, serialized);
        } else if (action == Action.Withdraw || action == Action.Borrow) {
            sequence = sendWormholeMessage(serialized);
        } else if (action == Action.DepositNative || action == Action.RepayNative) {
            sequence = sendTokenBridgeMessageNative(assetAmount + wormhole().messageFee(), serialized);
        }
    }
}