ETH Price: $2,621.65 (-4.03%)

Transaction Decoder

Block:
15010047 at Jun-22-2022 11:18:38 PM +UTC
Transaction Fee:
0.003870566334002732 ETH $10.15
Gas Used:
160,418 Gas / 24.128005174 Gwei

Emitted Events:

182 Registry.ExecutionCompleted( middlewareID=0, bridgeID=1, inputAmount=15000000000000000 )
183 TransparentUpgradeableProxy.0x23be8e12e420b5da9fb98d8102572f640fb3c11a0085060472dfc0ed194b3cf7( 0x23be8e12e420b5da9fb98d8102572f640fb3c11a0085060472dfc0ed194b3cf7, 0x0000000000000000000000000000000000000000000000000000000000089617, 0xa73115da15107254dcf4e5fff3c45a85e6dc312c9e47a70ed199afe0472970f0, 0000000000000000000000004dbd4fc535ac27206064b68ffcf827b0a60bab3f, 0000000000000000000000000000000000000000000000000000000000000009, 000000000000000000000000e7b49ba692773251e78ad50293cf4d64b67caa7a, 63780afbd9b5605f3b0ac409c318e9d62042da8c0b2a0726c35d377404a4f3e9 )
184 TransparentUpgradeableProxy.0xff64905f73a67fb594e0f940a8075a860db489ad991e032f48c81123eb52d60b( 0xff64905f73a67fb594e0f940a8075a860db489ad991e032f48c81123eb52d60b, 0x0000000000000000000000000000000000000000000000000000000000089617, 0000000000000000000000000000000000000000000000000000000000000020, 00000000000000000000000000000000000000000000000000000000000001e4, 0000000000000000000000003749c4f034022c39ecaffaba182555d4508caccc, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000000, 000000000000000000000000000000000000000000000000002386f26fc10000, 000000000000000000000000f8c59ba692773251e78ad50293cf4d64b67cbb8b, 000000000000000000000000f8c59ba692773251e78ad50293cf4d64b67cbb8b, 00000000000000000000000000000000000000000000000000000000004c4b40, 000000000000000000000000000000000000000000000000000000174876e800, 00000000000000000000000000000000000000000000000000000000000000c4, cc29a306000000000000000000000000b681e94cadf59bb445dd30439912e3e8, e6c8ea3200000000000000000000000000000000000000000000000000354a6b, a7a1800000000000000000000000000000000000000000000000000000327e5c, 774b1e2800000000000000000000000000000000000000000000000000000181, 8dc806ed00000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000000 )
185 L1_ETH_Bridge.TransferSentToL2( chainId=42161, recipient=[Sender] 0xb681e94cadf59bb445dd30439912e3e8e6c8ea32, amount=15000000000000000, amountOutMin=14212684439035432, deadline=1655941105389, relayer=0x00000000...000000000, relayerFee=0 )

Account State Difference:

  Address   Before After State Difference Code
0x011B6E24...BBc96D515
(Arbitrum: Old Bridge)
(F2Pool Old)
4,458.806296009394974419 Eth4,458.806536636394974419 Eth0.000240627
0xb681e94c...8e6C8eA32
0.02868945923506564 Eth
Nonce: 53
0.009818892901062908 Eth
Nonce: 54
0.018870566334002732
0xb8901acB...02919727f
(Hop Protocol: Ethereum Bridge)
13,331.946115407216041871 Eth13,331.961115407216041871 Eth0.015

Execution Trace

ETH 0.015 Registry.outboundTransferTo( _userRequest=[{name:receiverAddress, type:address, order:1, indexed:false, value:0xb681e94cadf59bb445Dd30439912E3e8e6C8eA32, valueString:0xb681e94cadf59bb445Dd30439912E3e8e6C8eA32}, {name:toChainId, type:uint256, order:2, indexed:false, value:42161, valueString:42161}, {name:amount, type:uint256, order:3, indexed:false, value:15000000000000000, valueString:15000000000000000}, {name:middlewareRequest, type:tuple, order:4, indexed:false, value:[{name:id, type:uint256, order:1, indexed:false, value:0, valueString:0}, {name:optionalNativeAmount, type:uint256, order:2, indexed:false, value:0, valueString:0}, {name:inputToken, type:address, order:3, indexed:false, value:0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE, valueString:0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE}, {name:data, type:bytes, order:4, indexed:false, value:0x, valueString:0x}], valueString:[{name:id, type:uint256, order:1, indexed:false, value:0, valueString:0}, {name:optionalNativeAmount, type:uint256, order:2, indexed:false, value:0, valueString:0}, {name:inputToken, type:address, order:3, indexed:false, value:0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE, valueString:0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE}, {name:data, type:bytes, order:4, indexed:false, value:0x, valueString:0x}]}, {name:bridgeRequest, type:tuple, order:5, indexed:false, value:[{name:id, type:uint256, order:1, indexed:false, value:1, valueString:1}, {name:optionalNativeAmount, type:uint256, order:2, indexed:false, value:0, valueString:0}, {name:inputToken, type:address, order:3, indexed:false, value:0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE, valueString:0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE}, {name:data, type:bytes, order:4, indexed:false, value:0x000000000000000000000000B8901ACB165ED027E32754E0FFE830802919727F000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000327E5C774B1E280000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001818DC806ED000000000000000000000000EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE, valueString:0x000000000000000000000000B8901ACB165ED027E32754E0FFE830802919727F000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000327E5C774B1E280000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001818DC806ED000000000000000000000000EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE}], valueString:[{name:id, type:uint256, order:1, indexed:false, value:1, valueString:1}, {name:optionalNativeAmount, type:uint256, order:2, indexed:false, value:0, valueString:0}, {name:inputToken, type:address, order:3, indexed:false, value:0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE, valueString:0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE}, {name:data, type:bytes, order:4, indexed:false, value:0x000000000000000000000000B8901ACB165ED027E32754E0FFE830802919727F000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000327E5C774B1E280000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001818DC806ED000000000000000000000000EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE, valueString:0x000000000000000000000000B8901ACB165ED027E32754E0FFE830802919727F000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000327E5C774B1E280000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001818DC806ED000000000000000000000000EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE}]}] )
  • ETH 0.015 HopImpl.outboundTransferTo( _amount=15000000000000000, _from=0xb681e94cadf59bb445Dd30439912E3e8e6C8eA32, _receiverAddress=0xb681e94cadf59bb445Dd30439912E3e8e6C8eA32, _token=0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE, _toChainId=42161, _extraData=0x000000000000000000000000B8901ACB165ED027E32754E0FFE830802919727F000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000327E5C774B1E280000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001818DC806ED000000000000000000000000EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE )
    • ETH 0.015 L1_ETH_Bridge.sendToL2( chainId=42161, recipient=0xb681e94cadf59bb445Dd30439912E3e8e6C8eA32, amount=15000000000000000, amountOutMin=14212684439035432, deadline=1655941105389, relayer=0x0000000000000000000000000000000000000000, relayerFee=0 )
      • ArbitrumMessengerWrapper.sendCrossDomainMessage( _calldata=0xCC29A306000000000000000000000000B681E94CADF59BB445DD30439912E3E8E6C8EA3200000000000000000000000000000000000000000000000000354A6BA7A1800000000000000000000000000000000000000000000000000000327E5C774B1E28000000000000000000000000000000000000000000000000000001818DC806ED00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 )
        • TransparentUpgradeableProxy.1b871c8d( )
          • Inbox.createRetryableTicketNoRefundAliasRewrite( destAddr=0x3749C4f034022c39ecafFaBA182555d4508caCCC, l2CallValue=0, maxSubmissionCost=10000000000000000, excessFeeRefundAddress=0xF8c59bA692773251E78AD50293Cf4d64B67cbb8B, callValueRefundAddress=0xF8c59bA692773251E78AD50293Cf4d64B67cbb8B, maxGas=5000000, gasPriceBid=100000000000, data=0xCC29A306000000000000000000000000B681E94CADF59BB445DD30439912E3E8E6C8EA3200000000000000000000000000000000000000000000000000354A6BA7A1800000000000000000000000000000000000000000000000000000327E5C774B1E28000000000000000000000000000000000000000000000000000001818DC806ED00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 ) => ( 562711 )
            • TransparentUpgradeableProxy.02bbfad1( )
              outboundTransferTo[Registry (ln:107)]
              File 1 of 7: Registry
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.4;
              import "@openzeppelin/contracts/access/Ownable.sol";
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
              import "./helpers/errors.sol";
              import "./ImplBase.sol";
              import "./MiddlewareImplBase.sol";
              /**
              // @title Movr Regisrtry Contract.
              // @notice This is the main contract that is called using fund movr.
              // This contains all the bridge and middleware ids. 
              // RouteIds signify which bridge to be used. 
              // Middleware Id signifies which aggregator will be used for swapping if required. 
              */
              contract Registry is Ownable {
                  using SafeERC20 for IERC20;
                  address private constant NATIVE_TOKEN_ADDRESS =
                      address(0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE);
                  ///@notice RouteData stores information for a route
                  struct RouteData {
                      address route;
                      bool isEnabled;
                      bool isMiddleware;
                  }
                  RouteData[] public routes;
                  modifier onlyExistingRoute(uint256 _routeId) {
                      require(
                          routes[_routeId].route != address(0),
                          MovrErrors.ROUTE_NOT_FOUND
                      );
                      _;
                  }
                  constructor(address _owner) Ownable() {
                      // first route is for direct bridging
                      routes.push(RouteData(NATIVE_TOKEN_ADDRESS, true, true));
                      transferOwnership(_owner);
                  }
                  // Function to receive Ether. msg.data must be empty
                  receive() external payable {}
                  //
                  // Events
                  //
                  event NewRouteAdded(
                      uint256 routeID,
                      address route,
                      bool isEnabled,
                      bool isMiddleware
                  );
                  event RouteDisabled(uint256 routeID);
                  event ExecutionCompleted(
                      uint256 middlewareID,
                      uint256 bridgeID,
                      uint256 inputAmount
                  );
                  /**
                  // @param id route id of middleware to be used
                  // @param optionalNativeAmount is the amount of native asset that the route requires 
                  // @param inputToken token address which will be swapped to
                  // BridgeRequest inputToken 
                  // @param data to be used by middleware
                  */
                  struct MiddlewareRequest {
                      uint256 id;
                      uint256 optionalNativeAmount;
                      address inputToken;
                      bytes data;
                  }
                  /**
                  // @param id route id of bridge to be used
                  // @param optionalNativeAmount optinal native amount, to be used
                  // when bridge needs native token along with ERC20    
                  // @param inputToken token addresss which will be bridged 
                  // @param data bridgeData to be used by bridge
                  */
                  struct BridgeRequest {
                      uint256 id;
                      uint256 optionalNativeAmount;
                      address inputToken;
                      bytes data;
                  }
                  /**
                  // @param receiverAddress Recipient address to recieve funds on destination chain
                  // @param toChainId Destination ChainId
                  // @param amount amount to be swapped if middlewareId is 0  it will be
                  // the amount to be bridged
                  // @param middlewareRequest middleware Requestdata
                  // @param bridgeRequest bridge request data
                  */
                  struct UserRequest {
                      address receiverAddress;
                      uint256 toChainId;
                      uint256 amount;
                      MiddlewareRequest middlewareRequest;
                      BridgeRequest bridgeRequest;
                  }
                  /**
                  // @notice function responsible for calling the respective implementation 
                  // depending on the bridge to be used
                  // If the middlewareId is 0 then no swap is required,
                  // we can directly bridge the source token to wherever required,
                  // else, we first call the Swap Impl Base for swapping to the required 
                  // token and then start the bridging
                  // @dev It is required for isMiddleWare to be true for route 0 as it is a special case
                  // @param _userRequest calldata follows the input data struct
                  */
                  function outboundTransferTo(UserRequest calldata _userRequest)
                      external
                      payable
                  {
                      require(_userRequest.amount != 0, MovrErrors.INVALID_AMT);
                      // make sure bridge ID is not 0
                      require(
                          _userRequest.bridgeRequest.id != 0,
                          MovrErrors.INVALID_BRIDGE_ID
                      );
                      // make sure bridge input is provided
                      require(
                          _userRequest.bridgeRequest.inputToken != address(0),
                          MovrErrors.ADDRESS_0_PROVIDED
                      );
                      // load middleware info and validate
                      RouteData memory middlewareInfo = routes[
                          _userRequest.middlewareRequest.id
                      ];
                      require(
                          middlewareInfo.route != address(0) &&
                              middlewareInfo.isEnabled &&
                              middlewareInfo.isMiddleware,
                          MovrErrors.ROUTE_NOT_ALLOWED
                      );
                      // load bridge info and validate
                      RouteData memory bridgeInfo = routes[_userRequest.bridgeRequest.id];
                      require(
                          bridgeInfo.route != address(0) &&
                              bridgeInfo.isEnabled &&
                              !bridgeInfo.isMiddleware,
                          MovrErrors.ROUTE_NOT_ALLOWED
                      );
                      emit ExecutionCompleted(
                          _userRequest.middlewareRequest.id,
                          _userRequest.bridgeRequest.id,
                          _userRequest.amount
                      );
                      // if middlewareID is 0 it means we dont want to perform a action before bridging
                      // and directly want to move for bridging
                      if (_userRequest.middlewareRequest.id == 0) {
                          // perform the bridging
                          ImplBase(bridgeInfo.route).outboundTransferTo{value: msg.value}(
                              _userRequest.amount,
                              msg.sender,
                              _userRequest.receiverAddress,
                              _userRequest.bridgeRequest.inputToken,
                              _userRequest.toChainId,
                              _userRequest.bridgeRequest.data
                          );
                          return;
                      }
                      // we first perform an action using the middleware
                      // we determine if the input asset is a native asset, if yes we pass
                      // the amount as value, else we pass the optionalNativeAmount
                      uint256 _amountOut = MiddlewareImplBase(middlewareInfo.route)
                          .performAction{
                          value: _userRequest.middlewareRequest.inputToken ==
                              NATIVE_TOKEN_ADDRESS
                              ? _userRequest.amount +
                                  _userRequest.middlewareRequest.optionalNativeAmount
                              : _userRequest.middlewareRequest.optionalNativeAmount
                      }(
                          msg.sender,
                          _userRequest.middlewareRequest.inputToken,
                          _userRequest.amount,
                          address(this),
                          _userRequest.middlewareRequest.data
                      );
                      // we mutate this variable if the input asset to bridge Impl is NATIVE
                      uint256 nativeInput = _userRequest.bridgeRequest.optionalNativeAmount;
                      // if the input asset is ERC20, we need to grant the bridge implementation approval
                      if (_userRequest.bridgeRequest.inputToken != NATIVE_TOKEN_ADDRESS) {
                          IERC20(_userRequest.bridgeRequest.inputToken).safeIncreaseAllowance(
                                  bridgeInfo.route,
                                  _amountOut
                              );
                      } else {
                          // if the input asset is native we need to set it as value
                          nativeInput =
                              _amountOut +
                              _userRequest.bridgeRequest.optionalNativeAmount;
                      }
                      // send off to bridge
                      ImplBase(bridgeInfo.route).outboundTransferTo{value: nativeInput}(
                          _amountOut,
                          address(this),
                          _userRequest.receiverAddress,
                          _userRequest.bridgeRequest.inputToken,
                          _userRequest.toChainId,
                          _userRequest.bridgeRequest.data
                      );
                  }
                  //
                  // Route management functions
                  //
                  /// @notice add routes to the registry.
                  function addRoutes(RouteData[] calldata _routes)
                      external
                      onlyOwner
                      returns (uint256[] memory)
                  {
                      require(_routes.length != 0, MovrErrors.EMPTY_INPUT);
                      uint256[] memory _routeIds = new uint256[](_routes.length);
                      for (uint256 i = 0; i < _routes.length; i++) {
                          require(
                              _routes[i].route != address(0),
                              MovrErrors.ADDRESS_0_PROVIDED
                          );
                          routes.push(_routes[i]);
                          _routeIds[i] = routes.length - 1;
                          emit NewRouteAdded(
                              i,
                              _routes[i].route,
                              _routes[i].isEnabled,
                              _routes[i].isMiddleware
                          );
                      }
                      return _routeIds;
                  }
                  ///@notice disables the route  if required.
                  function disableRoute(uint256 _routeId)
                      external
                      onlyOwner
                      onlyExistingRoute(_routeId)
                  {
                      routes[_routeId].isEnabled = false;
                      emit RouteDisabled(_routeId);
                  }
                  function rescueFunds(
                      address _token,
                      address _receiverAddress,
                      uint256 _amount
                  ) external onlyOwner {
                      IERC20(_token).safeTransfer(_receiverAddress, _amount);
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              import "../utils/Context.sol";
              /**
               * @dev Contract module which provides a basic access control mechanism, where
               * there is an account (an owner) that can be granted exclusive access to
               * specific functions.
               *
               * By default, the owner account will be the one that deploys the contract. This
               * can later be changed with {transferOwnership}.
               *
               * This module is used through inheritance. It will make available the modifier
               * `onlyOwner`, which can be applied to your functions to restrict their use to
               * the owner.
               */
              abstract contract Ownable is Context {
                  address private _owner;
                  event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                  /**
                   * @dev Initializes the contract setting the deployer as the initial owner.
                   */
                  constructor () {
                      address msgSender = _msgSender();
                      _owner = msgSender;
                      emit OwnershipTransferred(address(0), msgSender);
                  }
                  /**
                   * @dev Returns the address of the current owner.
                   */
                  function owner() public view virtual returns (address) {
                      return _owner;
                  }
                  /**
                   * @dev Throws if called by any account other than the owner.
                   */
                  modifier onlyOwner() {
                      require(owner() == _msgSender(), "Ownable: caller is not the owner");
                      _;
                  }
                  /**
                   * @dev Leaves the contract without owner. It will not be possible to call
                   * `onlyOwner` functions anymore. Can only be called by the current owner.
                   *
                   * NOTE: Renouncing ownership will leave the contract without an owner,
                   * thereby removing any functionality that is only available to the owner.
                   */
                  function renounceOwnership() public virtual onlyOwner {
                      emit OwnershipTransferred(_owner, address(0));
                      _owner = address(0);
                  }
                  /**
                   * @dev Transfers ownership of the contract to a new account (`newOwner`).
                   * Can only be called by the current owner.
                   */
                  function transferOwnership(address newOwner) public virtual onlyOwner {
                      require(newOwner != address(0), "Ownable: new owner is the zero address");
                      emit OwnershipTransferred(_owner, newOwner);
                      _owner = newOwner;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              /**
               * @dev Interface of the ERC20 standard as defined in the EIP.
               */
              interface IERC20 {
                  /**
                   * @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 `recipient`.
                   *
                   * Returns a boolean value indicating whether the operation succeeded.
                   *
                   * Emits a {Transfer} event.
                   */
                  function transfer(address recipient, 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 `sender` to `recipient` 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 sender, address recipient, uint256 amount) external returns (bool);
                  /**
                   * @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);
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              import "../IERC20.sol";
              import "../../../utils/Address.sol";
              /**
               * @title SafeERC20
               * @dev Wrappers around ERC20 operations that throw on failure (when the token
               * contract returns false). Tokens that return no value (and instead revert or
               * throw on failure) are also supported, non-reverting calls are assumed to be
               * successful.
               * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
               * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
               */
              library SafeERC20 {
                  using Address for address;
                  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'
                      // solhint-disable-next-line max-line-length
                      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));
                      }
                  }
                  /**
                   * @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
                          // solhint-disable-next-line max-line-length
                          require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.8.0;
              library MovrErrors {
                  string internal constant ADDRESS_0_PROVIDED = "ADDRESS_0_PROVIDED";
                  string internal constant EMPTY_INPUT = "EMPTY_INPUT";
                  string internal constant LENGTH_MISMATCH = "LENGTH_MISMATCH";
                  string internal constant INVALID_VALUE = "INVALID_VALUE";
                  string internal constant INVALID_AMT = "INVALID_AMT";
                  string internal constant IMPL_NOT_FOUND = "IMPL_NOT_FOUND";
                  string internal constant ROUTE_NOT_FOUND = "ROUTE_NOT_FOUND";
                  string internal constant IMPL_NOT_ALLOWED = "IMPL_NOT_ALLOWED";
                  string internal constant ROUTE_NOT_ALLOWED = "ROUTE_NOT_ALLOWED";
                  string internal constant INVALID_CHAIN_DATA = "INVALID_CHAIN_DATA";
                  string internal constant CHAIN_NOT_SUPPORTED = "CHAIN_NOT_SUPPORTED";
                  string internal constant TOKEN_NOT_SUPPORTED = "TOKEN_NOT_SUPPORTED";
                  string internal constant NOT_IMPLEMENTED = "NOT_IMPLEMENTED";
                  string internal constant INVALID_SENDER = "INVALID_SENDER";
                  string internal constant INVALID_BRIDGE_ID = "INVALID_BRIDGE_ID";
                  string internal constant MIDDLEWARE_ACTION_FAILED =
                      "MIDDLEWARE_ACTION_FAILED";
                  string internal constant VALUE_SHOULD_BE_ZERO = "VALUE_SHOULD_BE_ZERO";
                  string internal constant VALUE_SHOULD_NOT_BE_ZERO = "VALUE_SHOULD_NOT_BE_ZERO";
                  string internal constant VALUE_NOT_ENOUGH = "VALUE_NOT_ENOUGH";
                  string internal constant VALUE_NOT_EQUAL_TO_AMOUNT = "VALUE_NOT_EQUAL_TO_AMOUNT";
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.4;
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              import "@openzeppelin/contracts/access/Ownable.sol";
              import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
              import "./helpers/errors.sol";
              /**
              @title Abstract Implementation Contract.
              @notice All Bridge Implementation will follow this interface. 
              */
              abstract contract ImplBase is Ownable {
                  using SafeERC20 for IERC20;
                  address public registry;
                  address public constant NATIVE_TOKEN_ADDRESS =
                      address(0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE);
                  event UpdateRegistryAddress(address indexed registryAddress);
                  constructor(address _registry) Ownable() {
                      registry = _registry;
                  }
                  modifier onlyRegistry() {
                      require(msg.sender == registry, MovrErrors.INVALID_SENDER);
                      _;
                  }
                  function updateRegistryAddress(address newRegistry) external onlyOwner {
                      registry = newRegistry;
                      emit UpdateRegistryAddress(newRegistry);
                  }
                  function rescueFunds(
                      address token,
                      address userAddress,
                      uint256 amount
                  ) external onlyOwner {
                      IERC20(token).safeTransfer(userAddress, amount);
                  }
                  function outboundTransferTo(
                      uint256 _amount,
                      address _from,
                      address _receiverAddress,
                      address _token,
                      uint256 _toChainId,
                      bytes memory _extraData
                  ) external payable virtual;
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.4;
              import "@openzeppelin/contracts/access/Ownable.sol";
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
              import "./helpers/errors.sol";
              /**
              // @title Abstract Contract for middleware services.
              // @notice All middleware services will follow this interface. 
              */
              abstract contract MiddlewareImplBase is Ownable {
                  using SafeERC20 for IERC20;
                  address public immutable registry;
                  /// @notice only registry address is required.
                  constructor(address _registry) Ownable() {
                      registry = _registry;
                  }
                  modifier onlyRegistry {
                      require(msg.sender == registry, MovrErrors.INVALID_SENDER);
                      _;
                  }
                  function performAction(
                      address from,
                      address fromToken,
                      uint256 amount,
                      address receiverAddress,
                      bytes memory data
                  ) external payable virtual returns (uint256);
                  function rescueFunds(
                      address token,
                      address userAddress,
                      uint256 amount
                  ) external onlyOwner {
                      IERC20(token).safeTransfer(userAddress, amount);
                  }
              }
              // SPDX-License-Identifier: MIT
              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) {
                      this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
                      return msg.data;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              /**
               * @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
                   * ====
                   */
                  function isContract(address account) internal view returns (bool) {
                      // This method relies on extcodesize, which returns 0 for contracts in
                      // construction, since the code is only stored at the end of the
                      // constructor execution.
                      uint256 size;
                      // solhint-disable-next-line no-inline-assembly
                      assembly { size := extcodesize(account) }
                      return size > 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");
                      // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (bool success, bytes memory returndata) = target.delegatecall(data);
                      return _verifyCallResult(success, returndata, errorMessage);
                  }
                  function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private 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
                              // solhint-disable-next-line no-inline-assembly
                              assembly {
                                  let returndata_size := mload(returndata)
                                  revert(add(32, returndata), returndata_size)
                              }
                          } else {
                              revert(errorMessage);
                          }
                      }
                  }
              }
              

              File 2 of 7: TransparentUpgradeableProxy
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              /**
               * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
               * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
               * be specified by overriding the virtual {_implementation} function.
               *
               * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
               * different contract through the {_delegate} function.
               *
               * The success and return data of the delegated call will be returned back to the caller of the proxy.
               */
              abstract contract Proxy {
                  /**
                   * @dev Delegates the current call to `implementation`.
                   *
                   * This function does not return to its internall call site, it will return directly to the external caller.
                   */
                  function _delegate(address implementation) internal virtual {
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          // Copy msg.data. We take full control of memory in this inline assembly
                          // block because it will not return to Solidity code. We overwrite the
                          // Solidity scratch pad at memory position 0.
                          calldatacopy(0, 0, calldatasize())
                          // Call the implementation.
                          // out and outsize are 0 because we don't know the size yet.
                          let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
                          // Copy the returned data.
                          returndatacopy(0, 0, returndatasize())
                          switch result
                          // delegatecall returns 0 on error.
                          case 0 { revert(0, returndatasize()) }
                          default { return(0, returndatasize()) }
                      }
                  }
                  /**
                   * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
                   * and {_fallback} should delegate.
                   */
                  function _implementation() internal view virtual returns (address);
                  /**
                   * @dev Delegates the current call to the address returned by `_implementation()`.
                   *
                   * This function does not return to its internall call site, it will return directly to the external caller.
                   */
                  function _fallback() internal virtual {
                      _beforeFallback();
                      _delegate(_implementation());
                  }
                  /**
                   * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
                   * function in the contract matches the call data.
                   */
                  fallback () external payable virtual {
                      _fallback();
                  }
                  /**
                   * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
                   * is empty.
                   */
                  receive () external payable virtual {
                      _fallback();
                  }
                  /**
                   * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
                   * call, or as part of the Solidity `fallback` or `receive` functions.
                   *
                   * If overriden should call `super._beforeFallback()`.
                   */
                  function _beforeFallback() internal virtual {
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              import "./UpgradeableProxy.sol";
              /**
               * @dev This contract implements a proxy that is upgradeable by an admin.
               *
               * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
               * clashing], which can potentially be used in an attack, this contract uses the
               * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
               * things that go hand in hand:
               *
               * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
               * that call matches one of the admin functions exposed by the proxy itself.
               * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
               * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
               * "admin cannot fallback to proxy target".
               *
               * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
               * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
               * to sudden errors when trying to call a function from the proxy implementation.
               *
               * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
               * you should think of the `ProxyAdmin` instance as the real administrative interface of your proxy.
               */
              contract TransparentUpgradeableProxy is UpgradeableProxy {
                  /**
                   * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
                   * optionally initialized with `_data` as explained in {UpgradeableProxy-constructor}.
                   */
                  constructor(address _logic, address admin_, bytes memory _data) public payable UpgradeableProxy(_logic, _data) {
                      assert(_ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
                      _setAdmin(admin_);
                  }
                  /**
                   * @dev Emitted when the admin account has changed.
                   */
                  event AdminChanged(address previousAdmin, address newAdmin);
                  /**
                   * @dev Storage slot with the admin of the contract.
                   * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
                   * validated in the constructor.
                   */
                  bytes32 private constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                  /**
                   * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
                   */
                  modifier ifAdmin() {
                      if (msg.sender == _admin()) {
                          _;
                      } else {
                          _fallback();
                      }
                  }
                  /**
                   * @dev Returns the current admin.
                   *
                   * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
                   *
                   * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                   * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                   * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
                   */
                  function admin() external ifAdmin returns (address admin_) {
                      admin_ = _admin();
                  }
                  /**
                   * @dev Returns the current implementation.
                   *
                   * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
                   *
                   * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                   * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                   * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
                   */
                  function implementation() external ifAdmin returns (address implementation_) {
                      implementation_ = _implementation();
                  }
                  /**
                   * @dev Changes the admin of the proxy.
                   *
                   * Emits an {AdminChanged} event.
                   *
                   * NOTE: Only the admin can call this function. See {ProxyAdmin-changeProxyAdmin}.
                   */
                  function changeAdmin(address newAdmin) external virtual ifAdmin {
                      require(newAdmin != address(0), "TransparentUpgradeableProxy: new admin is the zero address");
                      emit AdminChanged(_admin(), newAdmin);
                      _setAdmin(newAdmin);
                  }
                  /**
                   * @dev Upgrade the implementation of the proxy.
                   *
                   * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
                   */
                  function upgradeTo(address newImplementation) external virtual ifAdmin {
                      _upgradeTo(newImplementation);
                  }
                  /**
                   * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
                   * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
                   * proxied contract.
                   *
                   * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
                   */
                  function upgradeToAndCall(address newImplementation, bytes calldata data) external payable virtual ifAdmin {
                      _upgradeTo(newImplementation);
                      Address.functionDelegateCall(newImplementation, data);
                  }
                  /**
                   * @dev Returns the current admin.
                   */
                  function _admin() internal view virtual returns (address adm) {
                      bytes32 slot = _ADMIN_SLOT;
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          adm := sload(slot)
                      }
                  }
                  /**
                   * @dev Stores a new address in the EIP1967 admin slot.
                   */
                  function _setAdmin(address newAdmin) private {
                      bytes32 slot = _ADMIN_SLOT;
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          sstore(slot, newAdmin)
                      }
                  }
                  /**
                   * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
                   */
                  function _beforeFallback() internal virtual override {
                      require(msg.sender != _admin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
                      super._beforeFallback();
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              import "./Proxy.sol";
              import "../utils/Address.sol";
              /**
               * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
               * implementation address that can be changed. This address is stored in storage in the location specified by
               * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
               * implementation behind the proxy.
               *
               * Upgradeability is only provided internally through {_upgradeTo}. For an externally upgradeable proxy see
               * {TransparentUpgradeableProxy}.
               */
              contract UpgradeableProxy is Proxy {
                  /**
                   * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
                   *
                   * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
                   * function call, and allows initializating the storage of the proxy like a Solidity constructor.
                   */
                  constructor(address _logic, bytes memory _data) public payable {
                      assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
                      _setImplementation(_logic);
                      if(_data.length > 0) {
                          Address.functionDelegateCall(_logic, _data);
                      }
                  }
                  /**
                   * @dev Emitted when the implementation is upgraded.
                   */
                  event Upgraded(address indexed implementation);
                  /**
                   * @dev Storage slot with the address of the current implementation.
                   * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
                   * validated in the constructor.
                   */
                  bytes32 private constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                  /**
                   * @dev Returns the current implementation address.
                   */
                  function _implementation() internal view virtual override returns (address impl) {
                      bytes32 slot = _IMPLEMENTATION_SLOT;
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          impl := sload(slot)
                      }
                  }
                  /**
                   * @dev Upgrades the proxy to a new implementation.
                   *
                   * Emits an {Upgraded} event.
                   */
                  function _upgradeTo(address newImplementation) internal virtual {
                      _setImplementation(newImplementation);
                      emit Upgraded(newImplementation);
                  }
                  /**
                   * @dev Stores a new address in the EIP1967 implementation slot.
                   */
                  function _setImplementation(address newImplementation) private {
                      require(Address.isContract(newImplementation), "UpgradeableProxy: new implementation is not a contract");
                      bytes32 slot = _IMPLEMENTATION_SLOT;
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          sstore(slot, newImplementation)
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.2 <0.8.0;
              /**
               * @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
                   * ====
                   */
                  function isContract(address account) internal view returns (bool) {
                      // This method relies on extcodesize, which returns 0 for contracts in
                      // construction, since the code is only stored at the end of the
                      // constructor execution.
                      uint256 size;
                      // solhint-disable-next-line no-inline-assembly
                      assembly { size := extcodesize(account) }
                      return size > 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");
                      // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (bool success, bytes memory returndata) = target.delegatecall(data);
                      return _verifyCallResult(success, returndata, errorMessage);
                  }
                  function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private 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
                              // solhint-disable-next-line no-inline-assembly
                              assembly {
                                  let returndata_size := mload(returndata)
                                  revert(add(32, returndata), returndata_size)
                              }
                          } else {
                              revert(errorMessage);
                          }
                      }
                  }
              }
              

              File 3 of 7: TransparentUpgradeableProxy
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              /**
               * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
               * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
               * be specified by overriding the virtual {_implementation} function.
               *
               * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
               * different contract through the {_delegate} function.
               *
               * The success and return data of the delegated call will be returned back to the caller of the proxy.
               */
              abstract contract Proxy {
                  /**
                   * @dev Delegates the current call to `implementation`.
                   *
                   * This function does not return to its internall call site, it will return directly to the external caller.
                   */
                  function _delegate(address implementation) internal virtual {
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          // Copy msg.data. We take full control of memory in this inline assembly
                          // block because it will not return to Solidity code. We overwrite the
                          // Solidity scratch pad at memory position 0.
                          calldatacopy(0, 0, calldatasize())
                          // Call the implementation.
                          // out and outsize are 0 because we don't know the size yet.
                          let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
                          // Copy the returned data.
                          returndatacopy(0, 0, returndatasize())
                          switch result
                          // delegatecall returns 0 on error.
                          case 0 { revert(0, returndatasize()) }
                          default { return(0, returndatasize()) }
                      }
                  }
                  /**
                   * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
                   * and {_fallback} should delegate.
                   */
                  function _implementation() internal view virtual returns (address);
                  /**
                   * @dev Delegates the current call to the address returned by `_implementation()`.
                   *
                   * This function does not return to its internall call site, it will return directly to the external caller.
                   */
                  function _fallback() internal virtual {
                      _beforeFallback();
                      _delegate(_implementation());
                  }
                  /**
                   * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
                   * function in the contract matches the call data.
                   */
                  fallback () external payable virtual {
                      _fallback();
                  }
                  /**
                   * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
                   * is empty.
                   */
                  receive () external payable virtual {
                      _fallback();
                  }
                  /**
                   * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
                   * call, or as part of the Solidity `fallback` or `receive` functions.
                   *
                   * If overriden should call `super._beforeFallback()`.
                   */
                  function _beforeFallback() internal virtual {
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              import "./UpgradeableProxy.sol";
              /**
               * @dev This contract implements a proxy that is upgradeable by an admin.
               *
               * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
               * clashing], which can potentially be used in an attack, this contract uses the
               * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
               * things that go hand in hand:
               *
               * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
               * that call matches one of the admin functions exposed by the proxy itself.
               * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
               * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
               * "admin cannot fallback to proxy target".
               *
               * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
               * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
               * to sudden errors when trying to call a function from the proxy implementation.
               *
               * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
               * you should think of the `ProxyAdmin` instance as the real administrative interface of your proxy.
               */
              contract TransparentUpgradeableProxy is UpgradeableProxy {
                  /**
                   * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
                   * optionally initialized with `_data` as explained in {UpgradeableProxy-constructor}.
                   */
                  constructor(address _logic, address admin_, bytes memory _data) public payable UpgradeableProxy(_logic, _data) {
                      assert(_ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
                      _setAdmin(admin_);
                  }
                  /**
                   * @dev Emitted when the admin account has changed.
                   */
                  event AdminChanged(address previousAdmin, address newAdmin);
                  /**
                   * @dev Storage slot with the admin of the contract.
                   * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
                   * validated in the constructor.
                   */
                  bytes32 private constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                  /**
                   * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
                   */
                  modifier ifAdmin() {
                      if (msg.sender == _admin()) {
                          _;
                      } else {
                          _fallback();
                      }
                  }
                  /**
                   * @dev Returns the current admin.
                   *
                   * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
                   *
                   * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                   * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                   * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
                   */
                  function admin() external ifAdmin returns (address admin_) {
                      admin_ = _admin();
                  }
                  /**
                   * @dev Returns the current implementation.
                   *
                   * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
                   *
                   * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                   * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                   * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
                   */
                  function implementation() external ifAdmin returns (address implementation_) {
                      implementation_ = _implementation();
                  }
                  /**
                   * @dev Changes the admin of the proxy.
                   *
                   * Emits an {AdminChanged} event.
                   *
                   * NOTE: Only the admin can call this function. See {ProxyAdmin-changeProxyAdmin}.
                   */
                  function changeAdmin(address newAdmin) external virtual ifAdmin {
                      require(newAdmin != address(0), "TransparentUpgradeableProxy: new admin is the zero address");
                      emit AdminChanged(_admin(), newAdmin);
                      _setAdmin(newAdmin);
                  }
                  /**
                   * @dev Upgrade the implementation of the proxy.
                   *
                   * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
                   */
                  function upgradeTo(address newImplementation) external virtual ifAdmin {
                      _upgradeTo(newImplementation);
                  }
                  /**
                   * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
                   * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
                   * proxied contract.
                   *
                   * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
                   */
                  function upgradeToAndCall(address newImplementation, bytes calldata data) external payable virtual ifAdmin {
                      _upgradeTo(newImplementation);
                      Address.functionDelegateCall(newImplementation, data);
                  }
                  /**
                   * @dev Returns the current admin.
                   */
                  function _admin() internal view virtual returns (address adm) {
                      bytes32 slot = _ADMIN_SLOT;
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          adm := sload(slot)
                      }
                  }
                  /**
                   * @dev Stores a new address in the EIP1967 admin slot.
                   */
                  function _setAdmin(address newAdmin) private {
                      bytes32 slot = _ADMIN_SLOT;
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          sstore(slot, newAdmin)
                      }
                  }
                  /**
                   * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
                   */
                  function _beforeFallback() internal virtual override {
                      require(msg.sender != _admin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
                      super._beforeFallback();
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              import "./Proxy.sol";
              import "../utils/Address.sol";
              /**
               * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
               * implementation address that can be changed. This address is stored in storage in the location specified by
               * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
               * implementation behind the proxy.
               *
               * Upgradeability is only provided internally through {_upgradeTo}. For an externally upgradeable proxy see
               * {TransparentUpgradeableProxy}.
               */
              contract UpgradeableProxy is Proxy {
                  /**
                   * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
                   *
                   * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
                   * function call, and allows initializating the storage of the proxy like a Solidity constructor.
                   */
                  constructor(address _logic, bytes memory _data) public payable {
                      assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
                      _setImplementation(_logic);
                      if(_data.length > 0) {
                          Address.functionDelegateCall(_logic, _data);
                      }
                  }
                  /**
                   * @dev Emitted when the implementation is upgraded.
                   */
                  event Upgraded(address indexed implementation);
                  /**
                   * @dev Storage slot with the address of the current implementation.
                   * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
                   * validated in the constructor.
                   */
                  bytes32 private constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                  /**
                   * @dev Returns the current implementation address.
                   */
                  function _implementation() internal view virtual override returns (address impl) {
                      bytes32 slot = _IMPLEMENTATION_SLOT;
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          impl := sload(slot)
                      }
                  }
                  /**
                   * @dev Upgrades the proxy to a new implementation.
                   *
                   * Emits an {Upgraded} event.
                   */
                  function _upgradeTo(address newImplementation) internal virtual {
                      _setImplementation(newImplementation);
                      emit Upgraded(newImplementation);
                  }
                  /**
                   * @dev Stores a new address in the EIP1967 implementation slot.
                   */
                  function _setImplementation(address newImplementation) private {
                      require(Address.isContract(newImplementation), "UpgradeableProxy: new implementation is not a contract");
                      bytes32 slot = _IMPLEMENTATION_SLOT;
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          sstore(slot, newImplementation)
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.2 <0.8.0;
              /**
               * @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
                   * ====
                   */
                  function isContract(address account) internal view returns (bool) {
                      // This method relies on extcodesize, which returns 0 for contracts in
                      // construction, since the code is only stored at the end of the
                      // constructor execution.
                      uint256 size;
                      // solhint-disable-next-line no-inline-assembly
                      assembly { size := extcodesize(account) }
                      return size > 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");
                      // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (bool success, bytes memory returndata) = target.delegatecall(data);
                      return _verifyCallResult(success, returndata, errorMessage);
                  }
                  function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private 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
                              // solhint-disable-next-line no-inline-assembly
                              assembly {
                                  let returndata_size := mload(returndata)
                                  revert(add(32, returndata), returndata_size)
                              }
                          } else {
                              revert(errorMessage);
                          }
                      }
                  }
              }
              

              File 4 of 7: L1_ETH_Bridge
              // SPDX-License-Identifier: MIT
              pragma solidity 0.6.12;
              pragma experimental ABIEncoderV2;
              import "./L1_Bridge.sol";
              /**
               * @dev A L1_Bridge that uses an ETH as the canonical token
               */
              contract L1_ETH_Bridge is L1_Bridge {
                  constructor (address[] memory bonders, address _governance) public L1_Bridge(bonders, _governance) {}
                  /* ========== Override Functions ========== */
                  function _transferFromBridge(address recipient, uint256 amount) internal override {
                      (bool success, ) = recipient.call{value: amount}(new bytes(0));
                      require(success, 'L1_ETH_BRG: ETH transfer failed');
                  }
                  function _transferToBridge(address /*from*/, uint256 amount) internal override {
                      require(msg.value == amount, "L1_ETH_BRG: Value does not match amount");
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity 0.6.12;
              pragma experimental ABIEncoderV2;
              import "./Bridge.sol";
              import "../interfaces/IMessengerWrapper.sol";
              /**
               * @dev L1_Bridge is responsible for the bonding and challenging of TransferRoots. All TransferRoots
               * originate in the L1_Bridge through `bondTransferRoot` and are propagated up to destination L2s.
               */
              abstract contract L1_Bridge is Bridge {
                  struct TransferBond {
                      address bonder;
                      uint256 createdAt;
                      uint256 totalAmount;
                      uint256 challengeStartTime;
                      address challenger;
                      bool challengeResolved;
                  }
                  /* ========== State ========== */
                  mapping(uint256 => mapping(bytes32 => uint256)) public transferRootCommittedAt;
                  mapping(bytes32 => TransferBond) public transferBonds;
                  mapping(uint256 => mapping(address => uint256)) public timeSlotToAmountBonded;
                  mapping(uint256 => uint256) public chainBalance;
                  /* ========== Config State ========== */
                  address public governance;
                  mapping(uint256 => IMessengerWrapper) public crossDomainMessengerWrappers;
                  mapping(uint256 => bool) public isChainIdPaused;
                  uint256 public challengePeriod = 1 days;
                  uint256 public challengeResolutionPeriod = 10 days;
                  uint256 public minTransferRootBondDelay = 15 minutes;
                  
                  uint256 public constant CHALLENGE_AMOUNT_DIVISOR = 10;
                  uint256 public constant TIME_SLOT_SIZE = 4 hours;
                  /* ========== Events ========== */
                  event TransferSentToL2(
                      uint256 indexed chainId,
                      address indexed recipient,
                      uint256 amount,
                      uint256 amountOutMin,
                      uint256 deadline,
                      address indexed relayer,
                      uint256 relayerFee
                  );
                  event TransferRootBonded (
                      bytes32 indexed root,
                      uint256 amount
                  );
                  event TransferRootConfirmed(
                      uint256 indexed originChainId,
                      uint256 indexed destinationChainId,
                      bytes32 indexed rootHash,
                      uint256 totalAmount
                  );
                  event TransferBondChallenged(
                      bytes32 indexed transferRootId,
                      bytes32 indexed rootHash,
                      uint256 originalAmount
                  );
                  event ChallengeResolved(
                      bytes32 indexed transferRootId,
                      bytes32 indexed rootHash,
                      uint256 originalAmount
                  );
                  /* ========== Modifiers ========== */
                  modifier onlyL2Bridge(uint256 chainId) {
                      IMessengerWrapper messengerWrapper = crossDomainMessengerWrappers[chainId];
                      messengerWrapper.verifySender(msg.sender, msg.data);
                      _;
                  }
                  constructor (address[] memory bonders, address _governance) public Bridge(bonders) {
                      governance = _governance;
                  }
                  /* ========== Send Functions ========== */
                  /**
                   * @notice `amountOutMin` and `deadline` should be 0 when no swap is intended at the destination.
                   * @notice `amount` is the total amount the user wants to send including the relayer fee
                   * @dev Send tokens to a supported layer-2 to mint hToken and optionally swap the hToken in the
                   * AMM at the destination.
                   * @param chainId The chainId of the destination chain
                   * @param recipient The address receiving funds at the destination
                   * @param amount The amount being sent
                   * @param amountOutMin The minimum amount received after attempting to swap in the destination
                   * AMM market. 0 if no swap is intended.
                   * @param deadline The deadline for swapping in the destination AMM market. 0 if no
                   * swap is intended.
                   * @param relayer The address of the relayer at the destination.
                   * @param relayerFee The amount distributed to the relayer at the destination. This is subtracted from the `amount`.
                   */
                  function sendToL2(
                      uint256 chainId,
                      address recipient,
                      uint256 amount,
                      uint256 amountOutMin,
                      uint256 deadline,
                      address relayer,
                      uint256 relayerFee
                  )
                      external
                      payable
                  {
                      IMessengerWrapper messengerWrapper = crossDomainMessengerWrappers[chainId];
                      require(messengerWrapper != IMessengerWrapper(0), "L1_BRG: chainId not supported");
                      require(isChainIdPaused[chainId] == false, "L1_BRG: Sends to this chainId are paused");
                      require(amount > 0, "L1_BRG: Must transfer a non-zero amount");
                      require(amount >= relayerFee, "L1_BRG: Relayer fee cannot exceed amount");
                      _transferToBridge(msg.sender, amount);
                      bytes memory message = abi.encodeWithSignature(
                          "distribute(address,uint256,uint256,uint256,address,uint256)",
                          recipient,
                          amount,
                          amountOutMin,
                          deadline,
                          relayer,
                          relayerFee
                      );
                      chainBalance[chainId] = chainBalance[chainId].add(amount);
                      messengerWrapper.sendCrossDomainMessage(message);
                      emit TransferSentToL2(
                          chainId,
                          recipient,
                          amount,
                          amountOutMin,
                          deadline,
                          relayer,
                          relayerFee
                      );
                  }
                  /* ========== TransferRoot Functions ========== */
                  /**
                   * @dev Setting a TransferRoot is a two step process.
                   * @dev   1. The TransferRoot is bonded with `bondTransferRoot`. Withdrawals can now begin on L1
                   * @dev      and recipient L2's
                   * @dev   2. The TransferRoot is confirmed after `confirmTransferRoot` is called by the l2 bridge
                   * @dev      where the TransferRoot originated.
                   */
                  /**
                   * @dev Used by the Bonder to bond a TransferRoot and propagate it up to destination L2s
                   * @param rootHash The Merkle root of the TransferRoot Merkle tree
                   * @param destinationChainId The id of the destination chain
                   * @param totalAmount The amount destined for the destination chain
                   */
                  function bondTransferRoot(
                      bytes32 rootHash,
                      uint256 destinationChainId,
                      uint256 totalAmount
                  )
                      external
                      onlyBonder
                      requirePositiveBalance
                  {
                      bytes32 transferRootId = getTransferRootId(rootHash, totalAmount);
                      require(transferRootCommittedAt[destinationChainId][transferRootId] == 0, "L1_BRG: TransferRoot has already been confirmed");
                      require(transferBonds[transferRootId].createdAt == 0, "L1_BRG: TransferRoot has already been bonded");
                      uint256 currentTimeSlot = getTimeSlot(block.timestamp);
                      uint256 bondAmount = getBondForTransferAmount(totalAmount);
                      timeSlotToAmountBonded[currentTimeSlot][msg.sender] = timeSlotToAmountBonded[currentTimeSlot][msg.sender].add(bondAmount);
                      transferBonds[transferRootId] = TransferBond(
                          msg.sender,
                          block.timestamp,
                          totalAmount,
                          uint256(0),
                          address(0),
                          false
                      );
                      _distributeTransferRoot(rootHash, destinationChainId, totalAmount);
                      emit TransferRootBonded(rootHash, totalAmount);
                  }
                  /**
                   * @dev Used by an L2 bridge to confirm a TransferRoot via cross-domain message. Once a TransferRoot
                   * has been confirmed, any challenge against that TransferRoot can be resolved as unsuccessful.
                   * @param originChainId The id of the origin chain
                   * @param rootHash The Merkle root of the TransferRoot Merkle tree
                   * @param destinationChainId The id of the destination chain
                   * @param totalAmount The amount destined for each destination chain
                   * @param rootCommittedAt The block timestamp when the TransferRoot was committed on its origin chain
                   */
                  function confirmTransferRoot(
                      uint256 originChainId,
                      bytes32 rootHash,
                      uint256 destinationChainId,
                      uint256 totalAmount,
                      uint256 rootCommittedAt
                  )
                      external
                      onlyL2Bridge(originChainId)
                  {
                      bytes32 transferRootId = getTransferRootId(rootHash, totalAmount);
                      require(transferRootCommittedAt[destinationChainId][transferRootId] == 0, "L1_BRG: TransferRoot already confirmed");
                      require(rootCommittedAt > 0, "L1_BRG: rootCommittedAt must be greater than 0");
                      transferRootCommittedAt[destinationChainId][transferRootId] = rootCommittedAt;
                      chainBalance[originChainId] = chainBalance[originChainId].sub(totalAmount, "L1_BRG: Amount exceeds chainBalance. This indicates a layer-2 failure.");
                      // If the TransferRoot was never bonded, distribute the TransferRoot.
                      TransferBond storage transferBond = transferBonds[transferRootId];
                      if (transferBond.createdAt == 0) {
                          _distributeTransferRoot(rootHash, destinationChainId, totalAmount);
                      }
                      emit TransferRootConfirmed(originChainId, destinationChainId, rootHash, totalAmount);
                  }
                  function _distributeTransferRoot(
                      bytes32 rootHash,
                      uint256 chainId,
                      uint256 totalAmount
                  )
                      internal
                  {
                      // Set TransferRoot on recipient Bridge
                      if (chainId == getChainId()) {
                          // Set L1 TransferRoot
                          _setTransferRoot(rootHash, totalAmount);
                      } else {
                          chainBalance[chainId] = chainBalance[chainId].add(totalAmount);
                          IMessengerWrapper messengerWrapper = crossDomainMessengerWrappers[chainId];
                          require(messengerWrapper != IMessengerWrapper(0), "L1_BRG: chainId not supported");
                          // Set L2 TransferRoot
                          bytes memory setTransferRootMessage = abi.encodeWithSignature(
                              "setTransferRoot(bytes32,uint256)",
                              rootHash,
                              totalAmount
                          );
                          messengerWrapper.sendCrossDomainMessage(setTransferRootMessage);
                      }
                  }
                  /* ========== External TransferRoot Challenges ========== */
                  /**
                   * @dev Challenge a TransferRoot believed to be fraudulent
                   * @param rootHash The Merkle root of the TransferRoot Merkle tree
                   * @param originalAmount The total amount bonded for this TransferRoot
                   * @param destinationChainId The id of the destination chain
                   */
                  function challengeTransferBond(bytes32 rootHash, uint256 originalAmount, uint256 destinationChainId) external payable {
                      bytes32 transferRootId = getTransferRootId(rootHash, originalAmount);
                      TransferBond storage transferBond = transferBonds[transferRootId];
                      require(transferRootCommittedAt[destinationChainId][transferRootId] == 0, "L1_BRG: TransferRoot has already been confirmed");
                      require(transferBond.createdAt != 0, "L1_BRG: TransferRoot has not been bonded");
                      uint256 challengePeriodEnd = transferBond.createdAt.add(challengePeriod);
                      require(challengePeriodEnd >= block.timestamp, "L1_BRG: TransferRoot cannot be challenged after challenge period");
                      require(transferBond.challengeStartTime == 0, "L1_BRG: TransferRoot already challenged");
                      transferBond.challengeStartTime = block.timestamp;
                      transferBond.challenger = msg.sender;
                      // Move amount from timeSlotToAmountBonded to debit
                      uint256 timeSlot = getTimeSlot(transferBond.createdAt);
                      uint256 bondAmount = getBondForTransferAmount(originalAmount);
                      address bonder = transferBond.bonder;
                      timeSlotToAmountBonded[timeSlot][bonder] = timeSlotToAmountBonded[timeSlot][bonder].sub(bondAmount);
                      _addDebit(transferBond.bonder, bondAmount);
                      // Get stake for challenge
                      uint256 challengeStakeAmount = getChallengeAmountForTransferAmount(originalAmount);
                      _transferToBridge(msg.sender, challengeStakeAmount);
                      emit TransferBondChallenged(transferRootId, rootHash, originalAmount);
                  }
                  /**
                   * @dev Resolve a challenge after the `challengeResolutionPeriod` has passed
                   * @param rootHash The Merkle root of the TransferRoot Merkle tree
                   * @param originalAmount The total amount originally bonded for this TransferRoot
                   * @param destinationChainId The id of the destination chain
                   */
                  function resolveChallenge(bytes32 rootHash, uint256 originalAmount, uint256 destinationChainId) external {
                      bytes32 transferRootId = getTransferRootId(rootHash, originalAmount);
                      TransferBond storage transferBond = transferBonds[transferRootId];
                      require(transferBond.challengeStartTime != 0, "L1_BRG: TransferRoot has not been challenged");
                      require(block.timestamp > transferBond.challengeStartTime.add(challengeResolutionPeriod), "L1_BRG: Challenge period has not ended");
                      require(transferBond.challengeResolved == false, "L1_BRG: TransferRoot already resolved");
                      transferBond.challengeResolved = true;
                      uint256 challengeStakeAmount = getChallengeAmountForTransferAmount(originalAmount);
                      if (transferRootCommittedAt[destinationChainId][transferRootId] > 0) {
                          // Invalid challenge
                          if (transferBond.createdAt > transferRootCommittedAt[destinationChainId][transferRootId].add(minTransferRootBondDelay)) {
                              // Credit the bonder back with the bond amount plus the challenger's stake
                              _addCredit(transferBond.bonder, getBondForTransferAmount(originalAmount).add(challengeStakeAmount));
                          } else {
                              // If the TransferRoot was bonded before it was committed, the challenger and Bonder
                              // get their stake back. This discourages Bonders from tricking challengers into
                              // challenging a valid TransferRoots that haven't yet been committed. It also ensures
                              // that Bonders are not punished if a TransferRoot is bonded too soon in error.
                              // Return the challenger's stake
                              _addCredit(transferBond.challenger, challengeStakeAmount);
                              // Credit the bonder back with the bond amount
                              _addCredit(transferBond.bonder, getBondForTransferAmount(originalAmount));
                          }
                      } else {
                          // Valid challenge
                          // Burn 25% of the challengers stake
                          _transferFromBridge(address(0xdead), challengeStakeAmount.mul(1).div(4));
                          // Reward challenger with the remaining 75% of their stake plus 100% of the Bonder's stake
                          _addCredit(transferBond.challenger, challengeStakeAmount.mul(7).div(4));
                      }
                      emit ChallengeResolved(transferRootId, rootHash, originalAmount);
                  }
                  /* ========== Override Functions ========== */
                  function _additionalDebit(address bonder) internal view override returns (uint256) {
                      uint256 currentTimeSlot = getTimeSlot(block.timestamp);
                      uint256 bonded = 0;
                      uint256 numTimeSlots = challengePeriod / TIME_SLOT_SIZE;
                      for (uint256 i = 0; i < numTimeSlots; i++) {
                          bonded = bonded.add(timeSlotToAmountBonded[currentTimeSlot - i][bonder]);
                      }
                      return bonded;
                  }
                  function _requireIsGovernance() internal override {
                      require(governance == msg.sender, "L1_BRG: Caller is not the owner");
                  }
                  /* ========== External Config Management Setters ========== */
                  function setGovernance(address _newGovernance) external onlyGovernance {
                      require(_newGovernance != address(0), "L1_BRG: _newGovernance cannot be address(0)");
                      governance = _newGovernance;
                  }
                  function setCrossDomainMessengerWrapper(uint256 chainId, IMessengerWrapper _crossDomainMessengerWrapper) external onlyGovernance {
                      crossDomainMessengerWrappers[chainId] = _crossDomainMessengerWrapper;
                  }
                  function setChainIdDepositsPaused(uint256 chainId, bool isPaused) external onlyGovernance {
                      isChainIdPaused[chainId] = isPaused;
                  }
                  function setChallengePeriod(uint256 _challengePeriod) external onlyGovernance {
                      require(_challengePeriod % TIME_SLOT_SIZE == 0, "L1_BRG: challengePeriod must be divisible by TIME_SLOT_SIZE");
                      challengePeriod = _challengePeriod;
                  }
                  function setChallengeResolutionPeriod(uint256 _challengeResolutionPeriod) external onlyGovernance {
                      challengeResolutionPeriod = _challengeResolutionPeriod;
                  }
                  function setMinTransferRootBondDelay(uint256 _minTransferRootBondDelay) external onlyGovernance {
                      minTransferRootBondDelay = _minTransferRootBondDelay;
                  }
                  /* ========== Public Getters ========== */
                  function getBondForTransferAmount(uint256 amount) public pure returns (uint256) {
                      // Bond covers amount plus a bounty to pay a potential challenger
                      return amount.add(getChallengeAmountForTransferAmount(amount));
                  }
                  function getChallengeAmountForTransferAmount(uint256 amount) public pure returns (uint256) {
                      // Bond covers amount plus a bounty to pay a potential challenger
                      return amount.div(CHALLENGE_AMOUNT_DIVISOR);
                  }
                  function getTimeSlot(uint256 time) public pure returns (uint256) {
                      return time / TIME_SLOT_SIZE;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity 0.6.12;
              pragma experimental ABIEncoderV2;
              import "./Accounting.sol";
              import "../libraries/Lib_MerkleTree.sol";
              /**
               * @dev Bridge extends the accounting system and encapsulates the logic that is shared by both the
               * L1 and L2 Bridges. It allows to TransferRoots to be set by parent contracts and for those
               * TransferRoots to be withdrawn against. It also allows the bonder to bond and withdraw Transfers
               * directly through `bondWithdrawal` and then settle those bonds against their TransferRoot once it
               * has been set.
               */
              abstract contract Bridge is Accounting {
                  using Lib_MerkleTree for bytes32;
                  struct TransferRoot {
                      uint256 total;
                      uint256 amountWithdrawn;
                      uint256 createdAt;
                  }
                  /* ========== Events ========== */
                  event Withdrew(
                      bytes32 indexed transferId,
                      address indexed recipient,
                      uint256 amount,
                      bytes32 transferNonce
                  );
                  event WithdrawalBonded(
                      bytes32 indexed transferId,
                      uint256 amount
                  );
                  event WithdrawalBondSettled(
                      address indexed bonder,
                      bytes32 indexed transferId,
                      bytes32 indexed rootHash
                  );
                  event MultipleWithdrawalsSettled(
                      address indexed bonder,
                      bytes32 indexed rootHash,
                      uint256 totalBondsSettled
                  );
                  event TransferRootSet(
                      bytes32 indexed rootHash,
                      uint256 totalAmount
                  );
                  /* ========== State ========== */
                  mapping(bytes32 => TransferRoot) private _transferRoots;
                  mapping(bytes32 => bool) private _spentTransferIds;
                  mapping(address => mapping(bytes32 => uint256)) private _bondedWithdrawalAmounts;
                  uint256 constant RESCUE_DELAY = 8 weeks;
                  constructor(address[] memory bonders) public Accounting(bonders) {}
                  /* ========== Public Getters ========== */
                  /**
                   * @dev Get the hash that represents an individual Transfer.
                   * @param chainId The id of the destination chain
                   * @param recipient The address receiving the Transfer
                   * @param amount The amount being transferred including the `_bonderFee`
                   * @param transferNonce Used to avoid transferId collisions
                   * @param bonderFee The amount paid to the address that withdraws the Transfer
                   * @param amountOutMin The minimum amount received after attempting to swap in the destination
                   * AMM market. 0 if no swap is intended.
                   * @param deadline The deadline for swapping in the destination AMM market. 0 if no
                   * swap is intended.
                   */
                  function getTransferId(
                      uint256 chainId,
                      address recipient,
                      uint256 amount,
                      bytes32 transferNonce,
                      uint256 bonderFee,
                      uint256 amountOutMin,
                      uint256 deadline
                  )
                      public
                      pure
                      returns (bytes32)
                  {
                      return keccak256(abi.encode(
                          chainId,
                          recipient,
                          amount,
                          transferNonce,
                          bonderFee,
                          amountOutMin,
                          deadline
                      ));
                  }
                  /**
                   * @notice getChainId can be overridden by subclasses if needed for compatibility or testing purposes.
                   * @dev Get the current chainId
                   * @return chainId The current chainId
                   */
                  function getChainId() public virtual view returns (uint256 chainId) {
                      this; // Silence state mutability warning without generating any additional byte code
                      assembly {
                          chainId := chainid()
                      }
                  }
                  /**
                   * @dev Get the TransferRoot id for a given rootHash and totalAmount
                   * @param rootHash The Merkle root of the TransferRoot
                   * @param totalAmount The total of all Transfers in the TransferRoot
                   * @return The calculated transferRootId
                   */
                  function getTransferRootId(bytes32 rootHash, uint256 totalAmount) public pure returns (bytes32) {
                      return keccak256(abi.encodePacked(rootHash, totalAmount));
                  }
                  /**
                   * @dev Get the TransferRoot for a given rootHash and totalAmount
                   * @param rootHash The Merkle root of the TransferRoot
                   * @param totalAmount The total of all Transfers in the TransferRoot
                   * @return The TransferRoot with the calculated transferRootId
                   */
                  function getTransferRoot(bytes32 rootHash, uint256 totalAmount) public view returns (TransferRoot memory) {
                      return _transferRoots[getTransferRootId(rootHash, totalAmount)];
                  }
                  /**
                   * @dev Get the amount bonded for the withdrawal of a transfer
                   * @param bonder The Bonder of the withdrawal
                   * @param transferId The Transfer's unique identifier
                   * @return The amount bonded for a Transfer withdrawal
                   */
                  function getBondedWithdrawalAmount(address bonder, bytes32 transferId) external view returns (uint256) {
                      return _bondedWithdrawalAmounts[bonder][transferId];
                  }
                  /**
                   * @dev Get the spent status of a transfer ID
                   * @param transferId The transfer's unique identifier
                   * @return True if the transferId has been spent
                   */
                  function isTransferIdSpent(bytes32 transferId) external view returns (bool) {
                      return _spentTransferIds[transferId];
                  }
                  /* ========== User/Relayer External Functions ========== */
                  /**
                   * @notice Can be called by anyone (recipient or relayer)
                   * @dev Withdraw a Transfer from its destination bridge
                   * @param recipient The address receiving the Transfer
                   * @param amount The amount being transferred including the `_bonderFee`
                   * @param transferNonce Used to avoid transferId collisions
                   * @param bonderFee The amount paid to the address that withdraws the Transfer
                   * @param amountOutMin The minimum amount received after attempting to swap in the destination
                   * AMM market. 0 if no swap is intended. (only used to calculate `transferId` in this function)
                   * @param deadline The deadline for swapping in the destination AMM market. 0 if no
                   * swap is intended. (only used to calculate `transferId` in this function)
                   * @param rootHash The Merkle root of the TransferRoot
                   * @param transferRootTotalAmount The total amount being transferred in a TransferRoot
                   * @param transferIdTreeIndex The index of the transferId in the Merkle tree
                   * @param siblings The siblings of the transferId in the Merkle tree
                   * @param totalLeaves The total number of leaves in the Merkle tree
                   */
                  function withdraw(
                      address recipient,
                      uint256 amount,
                      bytes32 transferNonce,
                      uint256 bonderFee,
                      uint256 amountOutMin,
                      uint256 deadline,
                      bytes32 rootHash,
                      uint256 transferRootTotalAmount,
                      uint256 transferIdTreeIndex,
                      bytes32[] calldata siblings,
                      uint256 totalLeaves
                  )
                      external
                      nonReentrant
                  {
                      bytes32 transferId = getTransferId(
                          getChainId(),
                          recipient,
                          amount,
                          transferNonce,
                          bonderFee,
                          amountOutMin,
                          deadline
                      );
                      require(
                          rootHash.verify(
                              transferId,
                              transferIdTreeIndex,
                              siblings,
                              totalLeaves
                          )
                      , "BRG: Invalid transfer proof");
                      bytes32 transferRootId = getTransferRootId(rootHash, transferRootTotalAmount);
                      _addToAmountWithdrawn(transferRootId, amount);
                      _fulfillWithdraw(transferId, recipient, amount, uint256(0));
                      emit Withdrew(transferId, recipient, amount, transferNonce);
                  }
                  /**
                   * @dev Allows the bonder to bond individual withdrawals before their TransferRoot has been committed.
                   * @param recipient The address receiving the Transfer
                   * @param amount The amount being transferred including the `_bonderFee`
                   * @param transferNonce Used to avoid transferId collisions
                   * @param bonderFee The amount paid to the address that withdraws the Transfer
                   */
                  function bondWithdrawal(
                      address recipient,
                      uint256 amount,
                      bytes32 transferNonce,
                      uint256 bonderFee
                  )
                      external
                      onlyBonder
                      requirePositiveBalance
                      nonReentrant
                  {
                      bytes32 transferId = getTransferId(
                          getChainId(),
                          recipient,
                          amount,
                          transferNonce,
                          bonderFee,
                          0,
                          0
                      );
                      _bondWithdrawal(transferId, amount);
                      _fulfillWithdraw(transferId, recipient, amount, bonderFee);
                  }
                  /**
                   * @dev Refunds the Bonder's stake from a bonded withdrawal and counts that withdrawal against
                   * its TransferRoot.
                   * @param bonder The Bonder of the withdrawal
                   * @param transferId The Transfer's unique identifier
                   * @param rootHash The Merkle root of the TransferRoot
                   * @param transferRootTotalAmount The total amount being transferred in a TransferRoot
                   * @param transferIdTreeIndex The index of the transferId in the Merkle tree
                   * @param siblings The siblings of the transferId in the Merkle tree
                   * @param totalLeaves The total number of leaves in the Merkle tree
                   */
                  function settleBondedWithdrawal(
                      address bonder,
                      bytes32 transferId,
                      bytes32 rootHash,
                      uint256 transferRootTotalAmount,
                      uint256 transferIdTreeIndex,
                      bytes32[] calldata siblings,
                      uint256 totalLeaves
                  )
                      external
                  {
                      require(
                          rootHash.verify(
                              transferId,
                              transferIdTreeIndex,
                              siblings,
                              totalLeaves
                          )
                      , "BRG: Invalid transfer proof");
                      bytes32 transferRootId = getTransferRootId(rootHash, transferRootTotalAmount);
                      uint256 amount = _bondedWithdrawalAmounts[bonder][transferId];
                      require(amount > 0, "L2_BRG: transferId has no bond");
                      _bondedWithdrawalAmounts[bonder][transferId] = 0;
                      _addToAmountWithdrawn(transferRootId, amount);
                      _addCredit(bonder, amount);
                      emit WithdrawalBondSettled(bonder, transferId, rootHash);
                  }
                  /**
                   * @dev Refunds the Bonder for all withdrawals that they bonded in a TransferRoot.
                   * @param bonder The address of the Bonder being refunded
                   * @param transferIds All transferIds in the TransferRoot in order
                   * @param totalAmount The totalAmount of the TransferRoot
                   */
                  function settleBondedWithdrawals(
                      address bonder,
                      // transferIds _must_ be calldata or it will be mutated by Lib_MerkleTree.getMerkleRoot
                      bytes32[] calldata transferIds,
                      uint256 totalAmount
                  )
                      external
                  {
                      bytes32 rootHash = Lib_MerkleTree.getMerkleRoot(transferIds);
                      bytes32 transferRootId = getTransferRootId(rootHash, totalAmount);
                      uint256 totalBondsSettled = 0;
                      for(uint256 i = 0; i < transferIds.length; i++) {
                          uint256 transferBondAmount = _bondedWithdrawalAmounts[bonder][transferIds[i]];
                          if (transferBondAmount > 0) {
                              totalBondsSettled = totalBondsSettled.add(transferBondAmount);
                              _bondedWithdrawalAmounts[bonder][transferIds[i]] = 0;
                          }
                      }
                      _addToAmountWithdrawn(transferRootId, totalBondsSettled);
                      _addCredit(bonder, totalBondsSettled);
                      emit MultipleWithdrawalsSettled(bonder, rootHash, totalBondsSettled);
                  }
                  /* ========== External TransferRoot Rescue ========== */
                  /**
                   * @dev Allows governance to withdraw the remaining amount from a TransferRoot after the rescue delay has passed.
                   * @param rootHash the Merkle root of the TransferRoot
                   * @param originalAmount The TransferRoot's recorded total
                   * @param recipient The address receiving the remaining balance
                   */
                  function rescueTransferRoot(bytes32 rootHash, uint256 originalAmount, address recipient) external onlyGovernance {
                      bytes32 transferRootId = getTransferRootId(rootHash, originalAmount);
                      TransferRoot memory transferRoot = getTransferRoot(rootHash, originalAmount);
                      require(transferRoot.createdAt != 0, "BRG: TransferRoot not found");
                      assert(transferRoot.total == originalAmount);
                      uint256 rescueDelayEnd = transferRoot.createdAt.add(RESCUE_DELAY);
                      require(block.timestamp >= rescueDelayEnd, "BRG: TransferRoot cannot be rescued before the Rescue Delay");
                      uint256 remainingAmount = transferRoot.total.sub(transferRoot.amountWithdrawn);
                      _addToAmountWithdrawn(transferRootId, remainingAmount);
                      _transferFromBridge(recipient, remainingAmount);
                  }
                  /* ========== Internal Functions ========== */
                  function _markTransferSpent(bytes32 transferId) internal {
                      require(!_spentTransferIds[transferId], "BRG: The transfer has already been withdrawn");
                      _spentTransferIds[transferId] = true;
                  }
                  function _addToAmountWithdrawn(bytes32 transferRootId, uint256 amount) internal {
                      TransferRoot storage transferRoot = _transferRoots[transferRootId];
                      require(transferRoot.total > 0, "BRG: Transfer root not found");
                      uint256 newAmountWithdrawn = transferRoot.amountWithdrawn.add(amount);
                      require(newAmountWithdrawn <= transferRoot.total, "BRG: Withdrawal exceeds TransferRoot total");
                      transferRoot.amountWithdrawn = newAmountWithdrawn;
                  }
                  function _setTransferRoot(bytes32 rootHash, uint256 totalAmount) internal {
                      bytes32 transferRootId = getTransferRootId(rootHash, totalAmount);
                      require(_transferRoots[transferRootId].total == 0, "BRG: Transfer root already set");
                      require(totalAmount > 0, "BRG: Cannot set TransferRoot totalAmount of 0");
                      _transferRoots[transferRootId] = TransferRoot(totalAmount, 0, block.timestamp);
                      emit TransferRootSet(rootHash, totalAmount);
                  }
                  function _bondWithdrawal(bytes32 transferId, uint256 amount) internal {
                      require(_bondedWithdrawalAmounts[msg.sender][transferId] == 0, "BRG: Withdrawal has already been bonded");
                      _addDebit(msg.sender, amount);
                      _bondedWithdrawalAmounts[msg.sender][transferId] = amount;
                      emit WithdrawalBonded(transferId, amount);
                  }
                  /* ========== Private Functions ========== */
                  /// @dev Completes the Transfer, distributes the Bonder fee and marks the Transfer as spent.
                  function _fulfillWithdraw(
                      bytes32 transferId,
                      address recipient,
                      uint256 amount,
                      uint256 bonderFee
                  ) private {
                      _markTransferSpent(transferId);
                      _transferFromBridge(recipient, amount.sub(bonderFee));
                      if (bonderFee > 0) {
                          _transferFromBridge(msg.sender, bonderFee);
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.12 <0.8.0;
              pragma experimental ABIEncoderV2;
              interface IMessengerWrapper {
                  function sendCrossDomainMessage(bytes memory _calldata) external;
                  function verifySender(address l1BridgeCaller, bytes memory _data) external;
              }
              // SPDX-License-Identifier: MIT
              pragma solidity 0.6.12;
              pragma experimental ABIEncoderV2;
              import "@openzeppelin/contracts/math/SafeMath.sol";
              import "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
              /**
               * @dev Accounting is an abstract contract that encapsulates the most critical logic in the Hop contracts.
               * The accounting system works by using two balances that can only increase `_credit` and `_debit`.
               * A bonder's available balance is the total credit minus the total debit. The contract exposes
               * two external functions that allows a bonder to stake and unstake and exposes two internal
               * functions to its child contracts that allow the child contract to add to the credit 
               * and debit balance. In addition, child contracts can override `_additionalDebit` to account
               * for any additional debit balance in an alternative way. Lastly, it exposes a modifier,
               * `requirePositiveBalance`, that can be used by child contracts to ensure the bonder does not
               * use more than its available stake.
               */
              abstract contract Accounting is ReentrancyGuard {
                  using SafeMath for uint256;
                  mapping(address => bool) private _isBonder;
                  mapping(address => uint256) private _credit;
                  mapping(address => uint256) private _debit;
                  event Stake (
                      address indexed account,
                      uint256 amount
                  );
                  event Unstake (
                      address indexed account,
                      uint256 amount
                  );
                  event BonderAdded (
                      address indexed newBonder
                  );
                  event BonderRemoved (
                      address indexed previousBonder
                  );
                  /* ========== Modifiers ========== */
                  modifier onlyBonder {
                      require(_isBonder[msg.sender], "ACT: Caller is not bonder");
                      _;
                  }
                  modifier onlyGovernance {
                      _requireIsGovernance();
                      _;
                  }
                  /// @dev Used by parent contract to ensure that the Bonder is solvent at the end of the transaction.
                  modifier requirePositiveBalance {
                      _;
                      require(getCredit(msg.sender) >= getDebitAndAdditionalDebit(msg.sender), "ACT: Not enough available credit");
                  }
                  /// @dev Sets the Bonder addresses
                  constructor(address[] memory bonders) public {
                      for (uint256 i = 0; i < bonders.length; i++) {
                          require(_isBonder[bonders[i]] == false, "ACT: Cannot add duplicate bonder");
                          _isBonder[bonders[i]] = true;
                          emit BonderAdded(bonders[i]);
                      }
                  }
                  /* ========== Virtual functions ========== */
                  /**
                   * @dev The following functions are overridden in L1_Bridge and L2_Bridge
                   */
                  function _transferFromBridge(address recipient, uint256 amount) internal virtual;
                  function _transferToBridge(address from, uint256 amount) internal virtual;
                  function _requireIsGovernance() internal virtual;
                  /**
                   * @dev This function can be optionally overridden by a parent contract to track any additional
                   * debit balance in an alternative way.
                   */
                  function _additionalDebit(address /*bonder*/) internal view virtual returns (uint256) {
                      this; // Silence state mutability warning without generating any additional byte code
                      return 0;
                  }
                  /* ========== Public/external getters ========== */
                  /**
                   * @dev Check if address is a Bonder
                   * @param maybeBonder The address being checked
                   * @return true if address is a Bonder
                   */
                  function getIsBonder(address maybeBonder) public view returns (bool) {
                      return _isBonder[maybeBonder];
                  }
                  /**
                   * @dev Get the Bonder's credit balance
                   * @param bonder The owner of the credit balance being checked
                   * @return The credit balance for the Bonder
                   */
                  function getCredit(address bonder) public view returns (uint256) {
                      return _credit[bonder];
                  }
                  /**
                   * @dev Gets the debit balance tracked by `_debit` and does not include `_additionalDebit()`
                   * @param bonder The owner of the debit balance being checked
                   * @return The debit amount for the Bonder
                   */
                  function getRawDebit(address bonder) external view returns (uint256) {
                      return _debit[bonder];
                  }
                  /**
                   * @dev Get the Bonder's total debit
                   * @param bonder The owner of the debit balance being checked
                   * @return The Bonder's total debit balance
                   */
                  function getDebitAndAdditionalDebit(address bonder) public view returns (uint256) {
                      return _debit[bonder].add(_additionalDebit(bonder));
                  }
                  /* ========== Bonder external functions ========== */
                  /** 
                   * @dev Allows the Bonder to deposit tokens and increase its credit balance
                   * @param bonder The address being staked on
                   * @param amount The amount being staked
                   */
                  function stake(address bonder, uint256 amount) external payable nonReentrant {
                      require(_isBonder[bonder] == true, "ACT: Address is not bonder");
                      _transferToBridge(msg.sender, amount);
                      _addCredit(bonder, amount);
                      emit Stake(bonder, amount);
                  }
                  /**
                   * @dev Allows the caller to withdraw any available balance and add to their debit balance
                   * @param amount The amount being unstaked
                   */
                  function unstake(uint256 amount) external requirePositiveBalance nonReentrant {
                      _addDebit(msg.sender, amount);
                      _transferFromBridge(msg.sender, amount);
                      emit Unstake(msg.sender, amount);
                  }
                  /**
                   * @dev Add Bonder to allowlist
                   * @param bonder The address being added as a Bonder
                   */
                  function addBonder(address bonder) external onlyGovernance {
                      require(_isBonder[bonder] == false, "ACT: Address is already bonder");
                      _isBonder[bonder] = true;
                      emit BonderAdded(bonder);
                  }
                  /**
                   * @dev Remove Bonder from allowlist
                   * @param bonder The address being removed as a Bonder
                   */
                  function removeBonder(address bonder) external onlyGovernance {
                      require(_isBonder[bonder] == true, "ACT: Address is not bonder");
                      _isBonder[bonder] = false;
                      emit BonderRemoved(bonder);
                  }
                  /* ========== Internal functions ========== */
                  function _addCredit(address bonder, uint256 amount) internal {
                      _credit[bonder] = _credit[bonder].add(amount);
                  }
                  function _addDebit(address bonder, uint256 amount) internal {
                      _debit[bonder] = _debit[bonder].add(amount);
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >0.5.0 <0.8.0;
              /**
               * @title Lib_MerkleTree
               * @author River Keefer
               */
              library Lib_MerkleTree {
                  /**********************
                   * Internal Functions *
                   **********************/
                  /**
                   * Calculates a merkle root for a list of 32-byte leaf hashes.  WARNING: If the number
                   * of leaves passed in is not a power of two, it pads out the tree with zero hashes.
                   * If you do not know the original length of elements for the tree you are verifying,
                   * then this may allow empty leaves past _elements.length to pass a verification check down the line.
                   * Note that the _elements argument is modified, therefore it must not be used again afterwards
                   * @param _elements Array of hashes from which to generate a merkle root.
                   * @return Merkle root of the leaves, with zero hashes for non-powers-of-two (see above).
                   */
                  function getMerkleRoot(
                      bytes32[] memory _elements
                  )
                      internal
                      pure
                      returns (
                          bytes32
                      )
                  {
                      require(
                          _elements.length > 0,
                          "Lib_MerkleTree: Must provide at least one leaf hash."
                      );
                      if (_elements.length == 1) {
                          return _elements[0];
                      }
                      uint256[16] memory defaults = [
                          0x290decd9548b62a8d60345a988386fc84ba6bc95484008f6362f93160ef3e563,
                          0x633dc4d7da7256660a892f8f1604a44b5432649cc8ec5cb3ced4c4e6ac94dd1d,
                          0x890740a8eb06ce9be422cb8da5cdafc2b58c0a5e24036c578de2a433c828ff7d,
                          0x3b8ec09e026fdc305365dfc94e189a81b38c7597b3d941c279f042e8206e0bd8,
                          0xecd50eee38e386bd62be9bedb990706951b65fe053bd9d8a521af753d139e2da,
                          0xdefff6d330bb5403f63b14f33b578274160de3a50df4efecf0e0db73bcdd3da5,
                          0x617bdd11f7c0a11f49db22f629387a12da7596f9d1704d7465177c63d88ec7d7,
                          0x292c23a9aa1d8bea7e2435e555a4a60e379a5a35f3f452bae60121073fb6eead,
                          0xe1cea92ed99acdcb045a6726b2f87107e8a61620a232cf4d7d5b5766b3952e10,
                          0x7ad66c0a68c72cb89e4fb4303841966e4062a76ab97451e3b9fb526a5ceb7f82,
                          0xe026cc5a4aed3c22a58cbd3d2ac754c9352c5436f638042dca99034e83636516,
                          0x3d04cffd8b46a874edf5cfae63077de85f849a660426697b06a829c70dd1409c,
                          0xad676aa337a485e4728a0b240d92b3ef7b3c372d06d189322bfd5f61f1e7203e,
                          0xa2fca4a49658f9fab7aa63289c91b7c7b6c832a6d0e69334ff5b0a3483d09dab,
                          0x4ebfd9cd7bca2505f7bef59cc1c12ecc708fff26ae4af19abe852afe9e20c862,
                          0x2def10d13dd169f550f578bda343d9717a138562e0093b380a1120789d53cf10
                      ];
                      // Reserve memory space for our hashes.
                      bytes memory buf = new bytes(64);
                      // We'll need to keep track of left and right siblings.
                      bytes32 leftSibling;
                      bytes32 rightSibling;
                      // Number of non-empty nodes at the current depth.
                      uint256 rowSize = _elements.length;
                      // Current depth, counting from 0 at the leaves
                      uint256 depth = 0;
                      // Common sub-expressions
                      uint256 halfRowSize;         // rowSize / 2
                      bool rowSizeIsOdd;           // rowSize % 2 == 1
                      while (rowSize > 1) {
                          halfRowSize = rowSize / 2;
                          rowSizeIsOdd = rowSize % 2 == 1;
                          for (uint256 i = 0; i < halfRowSize; i++) {
                              leftSibling  = _elements[(2 * i)    ];
                              rightSibling = _elements[(2 * i) + 1];
                              assembly {
                                  mstore(add(buf, 32), leftSibling )
                                  mstore(add(buf, 64), rightSibling)
                              }
                              _elements[i] = keccak256(buf);
                          }
                          if (rowSizeIsOdd) {
                              leftSibling  = _elements[rowSize - 1];
                              rightSibling = bytes32(defaults[depth]);
                              assembly {
                                  mstore(add(buf, 32), leftSibling)
                                  mstore(add(buf, 64), rightSibling)
                              }
                              _elements[halfRowSize] = keccak256(buf);
                          }
                          rowSize = halfRowSize + (rowSizeIsOdd ? 1 : 0);
                          depth++;
                      }
                      return _elements[0];
                  }
                  /**
                   * Verifies a merkle branch for the given leaf hash.  Assumes the original length
                   * of leaves generated is a known, correct input, and does not return true for indices
                   * extending past that index (even if _siblings would be otherwise valid.)
                   * @param _root The Merkle root to verify against.
                   * @param _leaf The leaf hash to verify inclusion of.
                   * @param _index The index in the tree of this leaf.
                   * @param _siblings Array of sibline nodes in the inclusion proof, starting from depth 0 (bottom of the tree).
                   * @param _totalLeaves The total number of leaves originally passed into.
                   * @return Whether or not the merkle branch and leaf passes verification.
                   */
                  function verify(
                      bytes32 _root,
                      bytes32 _leaf,
                      uint256 _index,
                      bytes32[] memory _siblings,
                      uint256 _totalLeaves
                  )
                      internal
                      pure
                      returns (
                          bool
                      )
                  {
                      require(
                          _totalLeaves > 0,
                          "Lib_MerkleTree: Total leaves must be greater than zero."
                      );
                      require(
                          _index < _totalLeaves,
                          "Lib_MerkleTree: Index out of bounds."
                      );
                      require(
                          _siblings.length == _ceilLog2(_totalLeaves),
                          "Lib_MerkleTree: Total siblings does not correctly correspond to total leaves."
                      );
                      bytes32 computedRoot = _leaf;
                      for (uint256 i = 0; i < _siblings.length; i++) {
                          if ((_index & 1) == 1) {
                              computedRoot = keccak256(
                                  abi.encodePacked(
                                      _siblings[i],
                                      computedRoot
                                  )
                              );
                          } else {
                              computedRoot = keccak256(
                                  abi.encodePacked(
                                      computedRoot,
                                      _siblings[i]
                                  )
                              );
                          }
                          _index >>= 1;
                      }
                      return _root == computedRoot;
                  }
                  /*********************
                   * Private Functions *
                   *********************/
                  /**
                   * Calculates the integer ceiling of the log base 2 of an input.
                   * @param _in Unsigned input to calculate the log.
                   * @return ceil(log_base_2(_in))
                   */
                  function _ceilLog2(
                      uint256 _in
                  )
                      private
                      pure
                      returns (
                          uint256
                      )
                  {
                      require(
                          _in > 0,
                          "Lib_MerkleTree: Cannot compute ceil(log_2) of 0."
                      );
                      if (_in == 1) {
                          return 0;
                      }
                      // Find the highest set bit (will be floor(log_2)).
                      // Borrowed with <3 from https://github.com/ethereum/solidity-examples
                      uint256 val = _in;
                      uint256 highest = 0;
                      for (uint256 i = 128; i >= 1; i >>= 1) {
                          if (val & (uint(1) << i) - 1 << i != 0) {
                              highest += i;
                              val >>= i;
                          }
                      }
                      // Increment by one if this is not a perfect logarithm.
                      if ((uint(1) << highest) != _in) {
                          highest += 1;
                      }
                      return highest;
                  }
              }// SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              /**
               * @dev Wrappers over Solidity's arithmetic operations with added overflow
               * checks.
               *
               * Arithmetic operations in Solidity wrap on overflow. This can easily result
               * in bugs, because programmers usually assume that an overflow raises an
               * error, which is the standard behavior in high level programming languages.
               * `SafeMath` restores this intuition by reverting the transaction when an
               * operation overflows.
               *
               * Using this library instead of the unchecked operations eliminates an entire
               * class of bugs, so it's recommended to use it always.
               */
              library SafeMath {
                  /**
                   * @dev Returns the addition of two unsigned integers, with an overflow flag.
                   *
                   * _Available since v3.4._
                   */
                  function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      uint256 c = a + b;
                      if (c < a) return (false, 0);
                      return (true, c);
                  }
                  /**
                   * @dev Returns the substraction of two unsigned integers, with an overflow flag.
                   *
                   * _Available since v3.4._
                   */
                  function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      if (b > a) return (false, 0);
                      return (true, a - b);
                  }
                  /**
                   * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
                   *
                   * _Available since v3.4._
                   */
                  function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                      // benefit is lost if 'b' is also tested.
                      // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                      if (a == 0) return (true, 0);
                      uint256 c = a * b;
                      if (c / a != b) return (false, 0);
                      return (true, c);
                  }
                  /**
                   * @dev Returns the division of two unsigned integers, with a division by zero flag.
                   *
                   * _Available since v3.4._
                   */
                  function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      if (b == 0) return (false, 0);
                      return (true, a / b);
                  }
                  /**
                   * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
                   *
                   * _Available since v3.4._
                   */
                  function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      if (b == 0) return (false, 0);
                      return (true, a % b);
                  }
                  /**
                   * @dev Returns the addition of two unsigned integers, reverting on
                   * overflow.
                   *
                   * Counterpart to Solidity's `+` operator.
                   *
                   * Requirements:
                   *
                   * - Addition cannot overflow.
                   */
                  function add(uint256 a, uint256 b) internal pure returns (uint256) {
                      uint256 c = a + b;
                      require(c >= a, "SafeMath: addition overflow");
                      return c;
                  }
                  /**
                   * @dev Returns the subtraction of two unsigned integers, reverting on
                   * overflow (when the result is negative).
                   *
                   * Counterpart to Solidity's `-` operator.
                   *
                   * Requirements:
                   *
                   * - Subtraction cannot overflow.
                   */
                  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                      require(b <= a, "SafeMath: subtraction overflow");
                      return a - b;
                  }
                  /**
                   * @dev Returns the multiplication of two unsigned integers, reverting on
                   * overflow.
                   *
                   * Counterpart to Solidity's `*` operator.
                   *
                   * Requirements:
                   *
                   * - Multiplication cannot overflow.
                   */
                  function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                      if (a == 0) return 0;
                      uint256 c = a * b;
                      require(c / a == b, "SafeMath: multiplication overflow");
                      return c;
                  }
                  /**
                   * @dev Returns the integer division of two unsigned integers, reverting on
                   * division by zero. The result is rounded towards zero.
                   *
                   * Counterpart to Solidity's `/` operator. Note: this function uses a
                   * `revert` opcode (which leaves remaining gas untouched) while Solidity
                   * uses an invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function div(uint256 a, uint256 b) internal pure returns (uint256) {
                      require(b > 0, "SafeMath: division by zero");
                      return a / b;
                  }
                  /**
                   * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                   * reverting when dividing by zero.
                   *
                   * Counterpart to Solidity's `%` operator. This function uses a `revert`
                   * opcode (which leaves remaining gas untouched) while Solidity uses an
                   * invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function mod(uint256 a, uint256 b) internal pure returns (uint256) {
                      require(b > 0, "SafeMath: modulo by zero");
                      return a % b;
                  }
                  /**
                   * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
                   * overflow (when the result is negative).
                   *
                   * CAUTION: This function is deprecated because it requires allocating memory for the error
                   * message unnecessarily. For custom revert reasons use {trySub}.
                   *
                   * Counterpart to Solidity's `-` operator.
                   *
                   * Requirements:
                   *
                   * - Subtraction cannot overflow.
                   */
                  function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                      require(b <= a, errorMessage);
                      return a - b;
                  }
                  /**
                   * @dev Returns the integer division of two unsigned integers, reverting with custom message on
                   * division by zero. The result is rounded towards zero.
                   *
                   * CAUTION: This function is deprecated because it requires allocating memory for the error
                   * message unnecessarily. For custom revert reasons use {tryDiv}.
                   *
                   * Counterpart to Solidity's `/` operator. Note: this function uses a
                   * `revert` opcode (which leaves remaining gas untouched) while Solidity
                   * uses an invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                      require(b > 0, errorMessage);
                      return a / b;
                  }
                  /**
                   * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                   * reverting with custom message when dividing by zero.
                   *
                   * CAUTION: This function is deprecated because it requires allocating memory for the error
                   * message unnecessarily. For custom revert reasons use {tryMod}.
                   *
                   * Counterpart to Solidity's `%` operator. This function uses a `revert`
                   * opcode (which leaves remaining gas untouched) while Solidity uses an
                   * invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                      require(b > 0, errorMessage);
                      return a % b;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              /**
               * @dev Contract module that helps prevent reentrant calls to a function.
               *
               * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
               * available, which can be applied to functions to make sure there are no nested
               * (reentrant) calls to them.
               *
               * Note that because there is a single `nonReentrant` guard, functions marked as
               * `nonReentrant` may not call one another. This can be worked around by making
               * those functions `private`, and then adding `external` `nonReentrant` entry
               * points to them.
               *
               * TIP: If you would like to learn more about reentrancy and alternative ways
               * to protect against it, check out our blog post
               * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
               */
              abstract contract ReentrancyGuard {
                  // Booleans are more expensive than uint256 or any type that takes up a full
                  // word because each write operation emits an extra SLOAD to first read the
                  // slot's contents, replace the bits taken up by the boolean, and then write
                  // back. This is the compiler's defense against contract upgrades and
                  // pointer aliasing, and it cannot be disabled.
                  // The values being non-zero value makes deployment a bit more expensive,
                  // but in exchange the refund on every call to nonReentrant will be lower in
                  // amount. Since refunds are capped to a percentage of the total
                  // transaction's gas, it is best to keep them low in cases like this one, to
                  // increase the likelihood of the full refund coming into effect.
                  uint256 private constant _NOT_ENTERED = 1;
                  uint256 private constant _ENTERED = 2;
                  uint256 private _status;
                  constructor () internal {
                      _status = _NOT_ENTERED;
                  }
                  /**
                   * @dev Prevents a contract from calling itself, directly or indirectly.
                   * Calling a `nonReentrant` function from another `nonReentrant`
                   * function is not supported. It is possible to prevent this from happening
                   * by making the `nonReentrant` function external, and make it call a
                   * `private` function that does the actual work.
                   */
                  modifier nonReentrant() {
                      // On the first call to nonReentrant, _notEntered will be true
                      require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
                      // Any calls to nonReentrant after this point will fail
                      _status = _ENTERED;
                      _;
                      // By storing the original value once again, a refund is triggered (see
                      // https://eips.ethereum.org/EIPS/eip-2200)
                      _status = _NOT_ENTERED;
                  }
              }
              

              File 5 of 7: HopImpl
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.8.0;
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
              import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
              import "../../ImplBase.sol";
              import "../../helpers/errors.sol";
              import "../../interfaces/hop/IHopL1Bridge.sol";
              /**
              // @title Hop Protocol Implementation.
              // @notice This is the L1 implementation, so this is used when transferring from l1 to supported l2s
              //         Called by the registry if the selected bridge is HOP.
              // @dev Follows the interface of ImplBase.
              // @author Movr Network.
              */
              contract HopImpl is ImplBase, ReentrancyGuard {
                  using SafeERC20 for IERC20;
                  // solhint-disable-next-line
                  constructor(address _registry) ImplBase(_registry) {}
                  /**
                  // @notice Function responsible for cross chain transfers from L1 to L2. 
                  // @dev When calling the registry the allowance should be given to this contract, 
                  //      that is the implementation contract for HOP.
                  // @param _amount amount to be transferred to L2.
                  // @param _from userAddress or address from which the transfer was made.
                  // @param _receiverAddress address that will receive the funds on the destination chain.
                  // @param _token address of the token to be used for cross chain transfer.
                  // @param _toChainId chain Id for the destination chain 
                  // @param _extraData parameters required to call the hop function in bytes 
                  */
                  function outboundTransferTo(
                      uint256 _amount,
                      address _from,
                      address _receiverAddress,
                      address _token,
                      uint256 _toChainId,
                      bytes memory _extraData
                  ) external payable override onlyRegistry nonReentrant {
                      // decode extra data
                      (
                          address _l1bridgeAddr,
                          address _relayer,
                          uint256 _amountOutMin,
                          uint256 _relayerFee,
                          uint256 _deadline
                      ) = abi.decode(
                              _extraData,
                              (address, address, uint256, uint256, uint256)
                          );
                      if (_token == NATIVE_TOKEN_ADDRESS) {
                          require(msg.value == _amount, MovrErrors.VALUE_NOT_EQUAL_TO_AMOUNT);
                          IHopL1Bridge(_l1bridgeAddr).sendToL2{value: _amount}(
                              _toChainId,
                              _receiverAddress,
                              _amount,
                              _amountOutMin,
                              _deadline,
                              _relayer,
                              _relayerFee
                          );
                          return;
                      }
                      require(msg.value == 0, MovrErrors.VALUE_SHOULD_BE_ZERO);
                      IERC20(_token).safeTransferFrom(_from, address(this), _amount);
                      IERC20(_token).safeIncreaseAllowance(_l1bridgeAddr, _amount);
                      // perform bridging
                      IHopL1Bridge(_l1bridgeAddr).sendToL2(
                          _toChainId,
                          _receiverAddress,
                          _amount,
                          _amountOutMin,
                          _deadline,
                          _relayer,
                          _relayerFee
                      );
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              /**
               * @dev Interface of the ERC20 standard as defined in the EIP.
               */
              interface IERC20 {
                  /**
                   * @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 `recipient`.
                   *
                   * Returns a boolean value indicating whether the operation succeeded.
                   *
                   * Emits a {Transfer} event.
                   */
                  function transfer(address recipient, 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 `sender` to `recipient` 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 sender, address recipient, uint256 amount) external returns (bool);
                  /**
                   * @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);
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              import "../IERC20.sol";
              import "../../../utils/Address.sol";
              /**
               * @title SafeERC20
               * @dev Wrappers around ERC20 operations that throw on failure (when the token
               * contract returns false). Tokens that return no value (and instead revert or
               * throw on failure) are also supported, non-reverting calls are assumed to be
               * successful.
               * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
               * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
               */
              library SafeERC20 {
                  using Address for address;
                  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'
                      // solhint-disable-next-line max-line-length
                      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));
                      }
                  }
                  /**
                   * @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
                          // solhint-disable-next-line max-line-length
                          require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              /**
               * @dev Contract module that helps prevent reentrant calls to a function.
               *
               * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
               * available, which can be applied to functions to make sure there are no nested
               * (reentrant) calls to them.
               *
               * Note that because there is a single `nonReentrant` guard, functions marked as
               * `nonReentrant` may not call one another. This can be worked around by making
               * those functions `private`, and then adding `external` `nonReentrant` entry
               * points to them.
               *
               * TIP: If you would like to learn more about reentrancy and alternative ways
               * to protect against it, check out our blog post
               * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
               */
              abstract contract ReentrancyGuard {
                  // Booleans are more expensive than uint256 or any type that takes up a full
                  // word because each write operation emits an extra SLOAD to first read the
                  // slot's contents, replace the bits taken up by the boolean, and then write
                  // back. This is the compiler's defense against contract upgrades and
                  // pointer aliasing, and it cannot be disabled.
                  // The values being non-zero value makes deployment a bit more expensive,
                  // but in exchange the refund on every call to nonReentrant will be lower in
                  // amount. Since refunds are capped to a percentage of the total
                  // transaction's gas, it is best to keep them low in cases like this one, to
                  // increase the likelihood of the full refund coming into effect.
                  uint256 private constant _NOT_ENTERED = 1;
                  uint256 private constant _ENTERED = 2;
                  uint256 private _status;
                  constructor () {
                      _status = _NOT_ENTERED;
                  }
                  /**
                   * @dev Prevents a contract from calling itself, directly or indirectly.
                   * Calling a `nonReentrant` function from another `nonReentrant`
                   * function is not supported. It is possible to prevent this from happening
                   * by making the `nonReentrant` function external, and make it call a
                   * `private` function that does the actual work.
                   */
                  modifier nonReentrant() {
                      // On the first call to nonReentrant, _notEntered will be true
                      require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
                      // Any calls to nonReentrant after this point will fail
                      _status = _ENTERED;
                      _;
                      // By storing the original value once again, a refund is triggered (see
                      // https://eips.ethereum.org/EIPS/eip-2200)
                      _status = _NOT_ENTERED;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.4;
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              import "@openzeppelin/contracts/access/Ownable.sol";
              import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
              import "./helpers/errors.sol";
              /**
              @title Abstract Implementation Contract.
              @notice All Bridge Implementation will follow this interface. 
              */
              abstract contract ImplBase is Ownable {
                  using SafeERC20 for IERC20;
                  address public registry;
                  address public constant NATIVE_TOKEN_ADDRESS =
                      address(0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE);
                  event UpdateRegistryAddress(address indexed registryAddress);
                  constructor(address _registry) Ownable() {
                      registry = _registry;
                  }
                  modifier onlyRegistry() {
                      require(msg.sender == registry, MovrErrors.INVALID_SENDER);
                      _;
                  }
                  function updateRegistryAddress(address newRegistry) external onlyOwner {
                      registry = newRegistry;
                      emit UpdateRegistryAddress(newRegistry);
                  }
                  function rescueFunds(
                      address token,
                      address userAddress,
                      uint256 amount
                  ) external onlyOwner {
                      IERC20(token).safeTransfer(userAddress, amount);
                  }
                  function outboundTransferTo(
                      uint256 _amount,
                      address _from,
                      address _receiverAddress,
                      address _token,
                      uint256 _toChainId,
                      bytes memory _extraData
                  ) external payable virtual;
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.8.0;
              library MovrErrors {
                  string internal constant ADDRESS_0_PROVIDED = "ADDRESS_0_PROVIDED";
                  string internal constant EMPTY_INPUT = "EMPTY_INPUT";
                  string internal constant LENGTH_MISMATCH = "LENGTH_MISMATCH";
                  string internal constant INVALID_VALUE = "INVALID_VALUE";
                  string internal constant INVALID_AMT = "INVALID_AMT";
                  string internal constant IMPL_NOT_FOUND = "IMPL_NOT_FOUND";
                  string internal constant ROUTE_NOT_FOUND = "ROUTE_NOT_FOUND";
                  string internal constant IMPL_NOT_ALLOWED = "IMPL_NOT_ALLOWED";
                  string internal constant ROUTE_NOT_ALLOWED = "ROUTE_NOT_ALLOWED";
                  string internal constant INVALID_CHAIN_DATA = "INVALID_CHAIN_DATA";
                  string internal constant CHAIN_NOT_SUPPORTED = "CHAIN_NOT_SUPPORTED";
                  string internal constant TOKEN_NOT_SUPPORTED = "TOKEN_NOT_SUPPORTED";
                  string internal constant NOT_IMPLEMENTED = "NOT_IMPLEMENTED";
                  string internal constant INVALID_SENDER = "INVALID_SENDER";
                  string internal constant INVALID_BRIDGE_ID = "INVALID_BRIDGE_ID";
                  string internal constant MIDDLEWARE_ACTION_FAILED =
                      "MIDDLEWARE_ACTION_FAILED";
                  string internal constant VALUE_SHOULD_BE_ZERO = "VALUE_SHOULD_BE_ZERO";
                  string internal constant VALUE_SHOULD_NOT_BE_ZERO = "VALUE_SHOULD_NOT_BE_ZERO";
                  string internal constant VALUE_NOT_ENOUGH = "VALUE_NOT_ENOUGH";
                  string internal constant VALUE_NOT_EQUAL_TO_AMOUNT = "VALUE_NOT_EQUAL_TO_AMOUNT";
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.4;
              /**
              @title L1Bridge Hop Interface
              @notice L1 Hop Bridge, Used to transfer from L1 to L2s. 
              */
              interface IHopL1Bridge {
                  function sendToL2(
                      uint256 chainId,
                      address recipient,
                      uint256 amount,
                      uint256 amountOutMin,
                      uint256 deadline,
                      address relayer,
                      uint256 relayerFee
                  ) external payable;
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              /**
               * @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
                   * ====
                   */
                  function isContract(address account) internal view returns (bool) {
                      // This method relies on extcodesize, which returns 0 for contracts in
                      // construction, since the code is only stored at the end of the
                      // constructor execution.
                      uint256 size;
                      // solhint-disable-next-line no-inline-assembly
                      assembly { size := extcodesize(account) }
                      return size > 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");
                      // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (bool success, bytes memory returndata) = target.delegatecall(data);
                      return _verifyCallResult(success, returndata, errorMessage);
                  }
                  function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private 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
                              // solhint-disable-next-line no-inline-assembly
                              assembly {
                                  let returndata_size := mload(returndata)
                                  revert(add(32, returndata), returndata_size)
                              }
                          } else {
                              revert(errorMessage);
                          }
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity ^0.8.0;
              import "../utils/Context.sol";
              /**
               * @dev Contract module which provides a basic access control mechanism, where
               * there is an account (an owner) that can be granted exclusive access to
               * specific functions.
               *
               * By default, the owner account will be the one that deploys the contract. This
               * can later be changed with {transferOwnership}.
               *
               * This module is used through inheritance. It will make available the modifier
               * `onlyOwner`, which can be applied to your functions to restrict their use to
               * the owner.
               */
              abstract contract Ownable is Context {
                  address private _owner;
                  event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                  /**
                   * @dev Initializes the contract setting the deployer as the initial owner.
                   */
                  constructor () {
                      address msgSender = _msgSender();
                      _owner = msgSender;
                      emit OwnershipTransferred(address(0), msgSender);
                  }
                  /**
                   * @dev Returns the address of the current owner.
                   */
                  function owner() public view virtual returns (address) {
                      return _owner;
                  }
                  /**
                   * @dev Throws if called by any account other than the owner.
                   */
                  modifier onlyOwner() {
                      require(owner() == _msgSender(), "Ownable: caller is not the owner");
                      _;
                  }
                  /**
                   * @dev Leaves the contract without owner. It will not be possible to call
                   * `onlyOwner` functions anymore. Can only be called by the current owner.
                   *
                   * NOTE: Renouncing ownership will leave the contract without an owner,
                   * thereby removing any functionality that is only available to the owner.
                   */
                  function renounceOwnership() public virtual onlyOwner {
                      emit OwnershipTransferred(_owner, address(0));
                      _owner = address(0);
                  }
                  /**
                   * @dev Transfers ownership of the contract to a new account (`newOwner`).
                   * Can only be called by the current owner.
                   */
                  function transferOwnership(address newOwner) public virtual onlyOwner {
                      require(newOwner != address(0), "Ownable: new owner is the zero address");
                      emit OwnershipTransferred(_owner, newOwner);
                      _owner = newOwner;
                  }
              }
              // SPDX-License-Identifier: MIT
              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) {
                      this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
                      return msg.data;
                  }
              }
              

              File 6 of 7: ArbitrumMessengerWrapper
              // SPDX-License-Identifier: MIT
              // @unsupported: ovm
              pragma solidity 0.6.12;
              pragma experimental ABIEncoderV2;
              import "@openzeppelin/contracts/access/Ownable.sol";
              import "../interfaces/arbitrum/messengers/IInbox.sol";
              import "../interfaces/arbitrum/messengers/IBridge.sol";
              import "../interfaces/arbitrum/messengers/IOutbox.sol";
              import "./MessengerWrapper.sol";
              /**
               * @dev A MessengerWrapper for Arbitrum - https://developer.offchainlabs.com/
               * @notice Deployed on layer-1
               */
              contract ArbitrumMessengerWrapper is MessengerWrapper, Ownable {
                  IInbox public immutable l1MessengerAddress;
                  address public l2BridgeAddress;
                  uint256 public maxSubmissionCost;
                  address public l1MessengerWrapperAlias;
                  uint256 public maxGas;
                  uint256 public gasPriceBid;
                  uint160 constant offset = uint160(0x1111000000000000000000000000000000001111);
                  constructor(
                      address _l1BridgeAddress,
                      address _l2BridgeAddress,
                      IInbox _l1MessengerAddress,
                      uint256 _maxSubmissionCost,
                      uint256 _maxGas,
                      uint256 _gasPriceBid
                      
                  )
                      public
                      MessengerWrapper(_l1BridgeAddress)
                  {
                      l2BridgeAddress = _l2BridgeAddress;
                      l1MessengerAddress = _l1MessengerAddress;
                      maxSubmissionCost = _maxSubmissionCost;
                      l1MessengerWrapperAlias = applyL1ToL2Alias(address(this));
                      maxGas = _maxGas;
                      gasPriceBid = _gasPriceBid;
                  }
                  /** 
                   * @dev Sends a message to the l2BridgeAddress from layer-1
                   * @param _calldata The data that l2BridgeAddress will be called with
                   */
                  function sendCrossDomainMessage(bytes memory _calldata) public override onlyL1Bridge {
                      l1MessengerAddress.createRetryableTicketNoRefundAliasRewrite(
                          l2BridgeAddress,
                          0,
                          maxSubmissionCost,
                          l1MessengerWrapperAlias,
                          l1MessengerWrapperAlias,
                          maxGas,
                          gasPriceBid,
                          _calldata
                      );
                  }
                  function verifySender(address l1BridgeCaller, bytes memory /*_data*/) public override {
                      // Reference: https://github.com/OffchainLabs/arbitrum/blob/5c06d89daf8fa6088bcdba292ffa6ed0c72afab2/packages/arb-bridge-peripherals/contracts/tokenbridge/ethereum/L1ArbitrumMessenger.sol#L89
                      IBridge arbBridge = l1MessengerAddress.bridge();
                      IOutbox outbox = IOutbox(arbBridge.activeOutbox());
                      address l2ToL1Sender = outbox.l2ToL1Sender();
                      require(l1BridgeCaller == address(arbBridge), "ARB_MSG_WPR: Caller is not the bridge");
                      require(l2ToL1Sender == l2BridgeAddress, "ARB_MSG_WPR: Invalid cross-domain sender");
                  }
                  /**
                   * @dev Claim funds that exist on the l2 messenger wrapper alias address
                   * @notice Do not use state variables here as this is to be used when passing in precise values
                   */
                  function claimL2Funds(
                      address _recipient,
                      uint256 _l2CallValue,
                      uint256 _maxSubmissionCost,
                      uint256 _maxGas,
                      uint256 _gasPriceBid
                  )
                      public
                      onlyOwner
                  {
                      l1MessengerAddress.createRetryableTicketNoRefundAliasRewrite(
                          _recipient,
                          _l2CallValue,
                          _maxSubmissionCost,
                          _recipient,
                          _recipient,
                          _maxGas,
                          _gasPriceBid,
                          ""
                      );
                  }
                  /// @notice Utility function that converts the msg.sender viewed in the L2 to the
                  /// address in the L1 that submitted a tx to the inbox
                  /// @param l1Address L2 address as viewed in msg.sender
                  /// @return The address in the L1 that triggered the tx to L2
                  function applyL1ToL2Alias(address l1Address) internal pure returns (address) {
                      return address(uint160(l1Address) + offset);
                  }
                  /* ========== External Config Management Functions ========== */
                  function setMaxSubmissionCost(uint256 _newMaxSubmissionCost) external onlyOwner {
                      maxSubmissionCost = _newMaxSubmissionCost;
                  }
                  function setL1MessengerWrapperAlias(address _newL1MessengerWrapperAlias) external onlyOwner {
                      l1MessengerWrapperAlias = _newL1MessengerWrapperAlias;
                  }
                  function setMaxGas(uint256 _newMaxGas) external onlyOwner {
                      maxGas = _newMaxGas;
                  }
                  function setGasPriceBid(uint256 _newGasPriceBid) external onlyOwner {
                      gasPriceBid = _newGasPriceBid;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              import "../utils/Context.sol";
              /**
               * @dev Contract module which provides a basic access control mechanism, where
               * there is an account (an owner) that can be granted exclusive access to
               * specific functions.
               *
               * By default, the owner account will be the one that deploys the contract. This
               * can later be changed with {transferOwnership}.
               *
               * This module is used through inheritance. It will make available the modifier
               * `onlyOwner`, which can be applied to your functions to restrict their use to
               * the owner.
               */
              abstract contract Ownable is Context {
                  address private _owner;
                  event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                  /**
                   * @dev Initializes the contract setting the deployer as the initial owner.
                   */
                  constructor () internal {
                      address msgSender = _msgSender();
                      _owner = msgSender;
                      emit OwnershipTransferred(address(0), msgSender);
                  }
                  /**
                   * @dev Returns the address of the current owner.
                   */
                  function owner() public view virtual returns (address) {
                      return _owner;
                  }
                  /**
                   * @dev Throws if called by any account other than the owner.
                   */
                  modifier onlyOwner() {
                      require(owner() == _msgSender(), "Ownable: caller is not the owner");
                      _;
                  }
                  /**
                   * @dev Leaves the contract without owner. It will not be possible to call
                   * `onlyOwner` functions anymore. Can only be called by the current owner.
                   *
                   * NOTE: Renouncing ownership will leave the contract without an owner,
                   * thereby removing any functionality that is only available to the owner.
                   */
                  function renounceOwnership() public virtual onlyOwner {
                      emit OwnershipTransferred(_owner, address(0));
                      _owner = address(0);
                  }
                  /**
                   * @dev Transfers ownership of the contract to a new account (`newOwner`).
                   * Can only be called by the current owner.
                   */
                  function transferOwnership(address newOwner) public virtual onlyOwner {
                      require(newOwner != address(0), "Ownable: new owner is the zero address");
                      emit OwnershipTransferred(_owner, newOwner);
                      _owner = newOwner;
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "./IBridge.sol";
              interface IInbox {
                  function sendL2Message(bytes calldata messageData) external returns (uint256);
                  function bridge() external view returns (IBridge);
                  function createRetryableTicketNoRefundAliasRewrite(
                      address destAddr,
                      uint256 l2CallValue,
                      uint256 maxSubmissionCost,
                      address excessFeeRefundAddress,
                      address callValueRefundAddress,
                      uint256 maxGas,
                      uint256 gasPriceBid,
                      bytes calldata data
                  ) external payable returns (uint256);
              }// SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              interface IBridge {
                  function activeOutbox() external view returns (address);
              }// SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              interface IOutbox {
                  function l2ToL1Sender() external view returns (address);
              }// SPDX-License-Identifier: MIT
              pragma solidity >=0.6.12 <=0.8.9;
              pragma experimental ABIEncoderV2;
              import "../interfaces/IMessengerWrapper.sol";
              abstract contract MessengerWrapper is IMessengerWrapper {
                  address public immutable l1BridgeAddress;
                  constructor(address _l1BridgeAddress) internal {
                      l1BridgeAddress = _l1BridgeAddress;
                  }
                  modifier onlyL1Bridge {
                      require(msg.sender == l1BridgeAddress, "MW: Sender must be the L1 Bridge");
                      _;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <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 GSN 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 payable) {
                      return msg.sender;
                  }
                  function _msgData() internal view virtual returns (bytes memory) {
                      this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
                      return msg.data;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.12 <=0.8.9;
              pragma experimental ABIEncoderV2;
              interface IMessengerWrapper {
                  function sendCrossDomainMessage(bytes memory _calldata) external;
                  function verifySender(address l1BridgeCaller, bytes memory _data) external;
              }
              

              File 7 of 7: Inbox
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2019-2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "./interfaces/IInbox.sol";
              import "./interfaces/IBridge.sol";
              import "../rollup/Rollup.sol";
              import "./Messages.sol";
              import "../libraries/Cloneable.sol";
              import "../libraries/Whitelist.sol";
              import "../libraries/ProxyUtil.sol";
              import "../libraries/AddressAliasHelper.sol";
              import "@openzeppelin/contracts/utils/Address.sol";
              import "./Bridge.sol";
              contract Inbox is IInbox, WhitelistConsumer, Cloneable {
                  uint8 internal constant ETH_TRANSFER = 0;
                  uint8 internal constant L2_MSG = 3;
                  uint8 internal constant L1MessageType_L2FundedByL1 = 7;
                  uint8 internal constant L1MessageType_submitRetryableTx = 9;
                  uint8 internal constant L2MessageType_unsignedEOATx = 0;
                  uint8 internal constant L2MessageType_unsignedContractTx = 1;
                  IBridge public override bridge;
                  bool public isCreateRetryablePaused;
                  bool public shouldRewriteSender;
                  function initialize(IBridge _bridge, address _whitelist) external {
                      require(address(bridge) == address(0), "ALREADY_INIT");
                      bridge = _bridge;
                      WhitelistConsumer.whitelist = _whitelist;
                  }
                  /**
                   * @notice Send a generic L2 message to the chain
                   * @dev This method is an optimization to avoid having to emit the entirety of the messageData in a log. Instead validators are expected to be able to parse the data from the transaction's input
                   * @param messageData Data of the message being sent
                   */
                  function sendL2MessageFromOrigin(bytes calldata messageData)
                      external
                      onlyWhitelisted
                      returns (uint256)
                  {
                      // solhint-disable-next-line avoid-tx-origin
                      require(msg.sender == tx.origin, "origin only");
                      uint256 msgNum = deliverToBridge(L2_MSG, msg.sender, keccak256(messageData));
                      emit InboxMessageDeliveredFromOrigin(msgNum);
                      return msgNum;
                  }
                  /**
                   * @notice Send a generic L2 message to the chain
                   * @dev This method can be used to send any type of message that doesn't require L1 validation
                   * @param messageData Data of the message being sent
                   */
                  function sendL2Message(bytes calldata messageData)
                      external
                      override
                      onlyWhitelisted
                      returns (uint256)
                  {
                      uint256 msgNum = deliverToBridge(L2_MSG, msg.sender, keccak256(messageData));
                      emit InboxMessageDelivered(msgNum, messageData);
                      return msgNum;
                  }
                  function sendL1FundedUnsignedTransaction(
                      uint256 maxGas,
                      uint256 gasPriceBid,
                      uint256 nonce,
                      address destAddr,
                      bytes calldata data
                  ) external payable virtual override onlyWhitelisted returns (uint256) {
                      return
                          _deliverMessage(
                              L1MessageType_L2FundedByL1,
                              msg.sender,
                              abi.encodePacked(
                                  L2MessageType_unsignedEOATx,
                                  maxGas,
                                  gasPriceBid,
                                  nonce,
                                  uint256(uint160(bytes20(destAddr))),
                                  msg.value,
                                  data
                              )
                          );
                  }
                  function sendL1FundedContractTransaction(
                      uint256 maxGas,
                      uint256 gasPriceBid,
                      address destAddr,
                      bytes calldata data
                  ) external payable virtual override onlyWhitelisted returns (uint256) {
                      return
                          _deliverMessage(
                              L1MessageType_L2FundedByL1,
                              msg.sender,
                              abi.encodePacked(
                                  L2MessageType_unsignedContractTx,
                                  maxGas,
                                  gasPriceBid,
                                  uint256(uint160(bytes20(destAddr))),
                                  msg.value,
                                  data
                              )
                          );
                  }
                  function sendUnsignedTransaction(
                      uint256 maxGas,
                      uint256 gasPriceBid,
                      uint256 nonce,
                      address destAddr,
                      uint256 amount,
                      bytes calldata data
                  ) external virtual override onlyWhitelisted returns (uint256) {
                      return
                          _deliverMessage(
                              L2_MSG,
                              msg.sender,
                              abi.encodePacked(
                                  L2MessageType_unsignedEOATx,
                                  maxGas,
                                  gasPriceBid,
                                  nonce,
                                  uint256(uint160(bytes20(destAddr))),
                                  amount,
                                  data
                              )
                          );
                  }
                  function sendContractTransaction(
                      uint256 maxGas,
                      uint256 gasPriceBid,
                      address destAddr,
                      uint256 amount,
                      bytes calldata data
                  ) external virtual override onlyWhitelisted returns (uint256) {
                      return
                          _deliverMessage(
                              L2_MSG,
                              msg.sender,
                              abi.encodePacked(
                                  L2MessageType_unsignedContractTx,
                                  maxGas,
                                  gasPriceBid,
                                  uint256(uint160(bytes20(destAddr))),
                                  amount,
                                  data
                              )
                          );
                  }
                  modifier onlyOwner() {
                      // the rollup contract owns the bridge
                      address rollup = Bridge(address(bridge)).owner();
                      // we want to validate the owner of the rollup
                      address owner = RollupBase(rollup).owner();
                      require(msg.sender == owner, "NOT_ROLLUP");
                      _;
                  }
                  event PauseToggled(bool enabled);
                  /// @notice pauses creating retryables
                  function pauseCreateRetryables() external override onlyOwner {
                      require(!isCreateRetryablePaused, "ALREADY_PAUSED");
                      isCreateRetryablePaused = true;
                      emit PauseToggled(true);
                  }
                  /// @notice unpauses creating retryables
                  function unpauseCreateRetryables() external override onlyOwner {
                      require(isCreateRetryablePaused, "NOT_PAUSED");
                      isCreateRetryablePaused = false;
                      emit PauseToggled(false);
                  }
                  event RewriteToggled(bool enabled);
                  /// @notice start rewriting addresses in eth deposits
                  function startRewriteAddress() external override onlyOwner {
                      require(!shouldRewriteSender, "ALREADY_REWRITING");
                      shouldRewriteSender = true;
                      emit RewriteToggled(true);
                  }
                  /// @notice stop rewriting addresses in eth deposits
                  function stopRewriteAddress() external override onlyOwner {
                      require(shouldRewriteSender, "NOT_REWRITING");
                      shouldRewriteSender = false;
                      emit RewriteToggled(false);
                  }
                  /// @notice deposit eth from L1 to L2
                  /// @dev this function should not be called inside contract constructors
                  function depositEth(uint256 maxSubmissionCost)
                      external
                      payable
                      virtual
                      override
                      onlyWhitelisted
                      returns (uint256)
                  {
                      require(!isCreateRetryablePaused, "CREATE_RETRYABLES_PAUSED");
                      address sender = msg.sender;
                      address destinationAddress = msg.sender;
                      if (shouldRewriteSender) {
                          if (!Address.isContract(sender) && tx.origin == msg.sender) {
                              // isContract check fails if this function is called during a contract's constructor.
                              // We don't adjust the address for calls coming from L1 contracts since their addresses get remapped
                              // If the caller is an EOA, we adjust the address.
                              // This is needed because unsigned messages to the L2 (such as retryables)
                              // have the L1 sender address mapped.
                              // Here we preemptively reverse the mapping for EOAs so deposits work as expected
                              sender = AddressAliasHelper.undoL1ToL2Alias(sender);
                          } else {
                              destinationAddress = AddressAliasHelper.applyL1ToL2Alias(destinationAddress);
                          }
                      }
                      return
                          _deliverMessage(
                              L1MessageType_submitRetryableTx,
                              sender,
                              abi.encodePacked(
                                  // the beneficiary and other refund addresses don't get rewritten by arb-os
                                  // so we use the original msg.sender value
                                  uint256(uint160(bytes20(destinationAddress))),
                                  uint256(0),
                                  msg.value,
                                  maxSubmissionCost,
                                  uint256(uint160(bytes20(destinationAddress))),
                                  uint256(uint160(bytes20(destinationAddress))),
                                  uint256(0),
                                  uint256(0),
                                  uint256(0),
                                  ""
                              )
                          );
                  }
                  /**
                   * @notice will be deprecated post-nitro in favour of unsafeCreateRetryableTicket
                   * @notice Put a message in the L2 inbox that can be reexecuted for some fixed amount of time if it reverts
                   * @dev Advanced usage only (does not rewrite aliases for excessFeeRefundAddress and callValueRefundAddress). createRetryableTicket method is the recommended standard.
                   * @param destAddr destination L2 contract address
                   * @param l2CallValue call value for retryable L2 message
                   * @param  maxSubmissionCost Max gas deducted from user's L2 balance to cover base submission fee
                   * @param excessFeeRefundAddress maxgas x gasprice - execution cost gets credited here on L2 balance
                   * @param callValueRefundAddress l2Callvalue gets credited here on L2 if retryable txn times out or gets cancelled
                   * @param maxGas Max gas deducted from user's L2 balance to cover L2 execution
                   * @param gasPriceBid price bid for L2 execution
                   * @param data ABI encoded data of L2 message
                   * @return unique id for retryable transaction (keccak256(requestID, uint(0) )
                   */
                  function createRetryableTicketNoRefundAliasRewrite(
                      address destAddr,
                      uint256 l2CallValue,
                      uint256 maxSubmissionCost,
                      address excessFeeRefundAddress,
                      address callValueRefundAddress,
                      uint256 maxGas,
                      uint256 gasPriceBid,
                      bytes calldata data
                  ) public payable virtual onlyWhitelisted returns (uint256) {
                      require(!isCreateRetryablePaused, "CREATE_RETRYABLES_PAUSED");
                      return
                          _deliverMessage(
                              L1MessageType_submitRetryableTx,
                              msg.sender,
                              abi.encodePacked(
                                  uint256(uint160(bytes20(destAddr))),
                                  l2CallValue,
                                  msg.value,
                                  maxSubmissionCost,
                                  uint256(uint160(bytes20(excessFeeRefundAddress))),
                                  uint256(uint160(bytes20(callValueRefundAddress))),
                                  maxGas,
                                  gasPriceBid,
                                  data.length,
                                  data
                              )
                          );
                  }
                  /**
                   * @notice Put a message in the L2 inbox that can be reexecuted for some fixed amount of time if it reverts
                   * @dev all msg.value will deposited to callValueRefundAddress on L2
                   * @param destAddr destination L2 contract address
                   * @param l2CallValue call value for retryable L2 message
                   * @param  maxSubmissionCost Max gas deducted from user's L2 balance to cover base submission fee
                   * @param excessFeeRefundAddress maxgas x gasprice - execution cost gets credited here on L2 balance
                   * @param callValueRefundAddress l2Callvalue gets credited here on L2 if retryable txn times out or gets cancelled
                   * @param maxGas Max gas deducted from user's L2 balance to cover L2 execution
                   * @param gasPriceBid price bid for L2 execution
                   * @param data ABI encoded data of L2 message
                   * @return unique id for retryable transaction (keccak256(requestID, uint(0) )
                   */
                  function createRetryableTicket(
                      address destAddr,
                      uint256 l2CallValue,
                      uint256 maxSubmissionCost,
                      address excessFeeRefundAddress,
                      address callValueRefundAddress,
                      uint256 maxGas,
                      uint256 gasPriceBid,
                      bytes calldata data
                  ) external payable virtual override onlyWhitelisted returns (uint256) {
                      // ensure the user's deposit alone will make submission succeed
                      require(msg.value >= maxSubmissionCost + l2CallValue, "insufficient value");
                      // if a refund address is a contract, we apply the alias to it
                      // so that it can access its funds on the L2
                      // since the beneficiary and other refund addresses don't get rewritten by arb-os
                      if (shouldRewriteSender && Address.isContract(excessFeeRefundAddress)) {
                          excessFeeRefundAddress = AddressAliasHelper.applyL1ToL2Alias(excessFeeRefundAddress);
                      }
                      if (shouldRewriteSender && Address.isContract(callValueRefundAddress)) {
                          // this is the beneficiary. be careful since this is the address that can cancel the retryable in the L2
                          callValueRefundAddress = AddressAliasHelper.applyL1ToL2Alias(callValueRefundAddress);
                      }
                      return
                          createRetryableTicketNoRefundAliasRewrite(
                              destAddr,
                              l2CallValue,
                              maxSubmissionCost,
                              excessFeeRefundAddress,
                              callValueRefundAddress,
                              maxGas,
                              gasPriceBid,
                              data
                          );
                  }
                  /**
                   * @notice Put a message in the L2 inbox that can be reexecuted for some fixed amount of time if it reverts
                   * @dev Advanced usage only (does not rewrite aliases for excessFeeRefundAddress and callValueRefundAddress). createRetryableTicket method is the recommended standard.
                   * @param destAddr destination L2 contract address
                   * @param l2CallValue call value for retryable L2 message
                   * @param  maxSubmissionCost Max gas deducted from user's L2 balance to cover base submission fee
                   * @param excessFeeRefundAddress maxgas x gasprice - execution cost gets credited here on L2 balance
                   * @param callValueRefundAddress l2Callvalue gets credited here on L2 if retryable txn times out or gets cancelled
                   * @param maxGas Max gas deducted from user's L2 balance to cover L2 execution
                   * @param gasPriceBid price bid for L2 execution
                   * @param data ABI encoded data of L2 message
                   * @return unique id for retryable transaction (keccak256(requestID, uint(0) )
                   */
                  function unsafeCreateRetryableTicket(
                      address destAddr,
                      uint256 l2CallValue,
                      uint256 maxSubmissionCost,
                      address excessFeeRefundAddress,
                      address callValueRefundAddress,
                      uint256 maxGas,
                      uint256 gasPriceBid,
                      bytes calldata data
                  ) external payable virtual returns (uint256) {
                      return
                          createRetryableTicketNoRefundAliasRewrite(
                              destAddr,
                              l2CallValue,
                              maxSubmissionCost,
                              excessFeeRefundAddress,
                              callValueRefundAddress,
                              maxGas,
                              gasPriceBid,
                              data
                          );
                  }
                  function _deliverMessage(
                      uint8 _kind,
                      address _sender,
                      bytes memory _messageData
                  ) internal returns (uint256) {
                      uint256 msgNum = deliverToBridge(_kind, _sender, keccak256(_messageData));
                      emit InboxMessageDelivered(msgNum, _messageData);
                      return msgNum;
                  }
                  function deliverToBridge(
                      uint8 kind,
                      address sender,
                      bytes32 messageDataHash
                  ) internal returns (uint256) {
                      return bridge.deliverMessageToInbox{ value: msg.value }(kind, sender, messageDataHash);
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "./IBridge.sol";
              import "./IMessageProvider.sol";
              interface IInbox is IMessageProvider {
                  function sendL2Message(bytes calldata messageData) external returns (uint256);
                  function sendUnsignedTransaction(
                      uint256 maxGas,
                      uint256 gasPriceBid,
                      uint256 nonce,
                      address destAddr,
                      uint256 amount,
                      bytes calldata data
                  ) external returns (uint256);
                  function sendContractTransaction(
                      uint256 maxGas,
                      uint256 gasPriceBid,
                      address destAddr,
                      uint256 amount,
                      bytes calldata data
                  ) external returns (uint256);
                  function sendL1FundedUnsignedTransaction(
                      uint256 maxGas,
                      uint256 gasPriceBid,
                      uint256 nonce,
                      address destAddr,
                      bytes calldata data
                  ) external payable returns (uint256);
                  function sendL1FundedContractTransaction(
                      uint256 maxGas,
                      uint256 gasPriceBid,
                      address destAddr,
                      bytes calldata data
                  ) external payable returns (uint256);
                  function createRetryableTicket(
                      address destAddr,
                      uint256 arbTxCallValue,
                      uint256 maxSubmissionCost,
                      address submissionRefundAddress,
                      address valueRefundAddress,
                      uint256 maxGas,
                      uint256 gasPriceBid,
                      bytes calldata data
                  ) external payable returns (uint256);
                  function depositEth(uint256 maxSubmissionCost) external payable returns (uint256);
                  function bridge() external view returns (IBridge);
                  function pauseCreateRetryables() external;
                  function unpauseCreateRetryables() external;
                  function startRewriteAddress() external;
                  function stopRewriteAddress() external;
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              interface IBridge {
                  event MessageDelivered(
                      uint256 indexed messageIndex,
                      bytes32 indexed beforeInboxAcc,
                      address inbox,
                      uint8 kind,
                      address sender,
                      bytes32 messageDataHash
                  );
                  event BridgeCallTriggered(
                      address indexed outbox,
                      address indexed destAddr,
                      uint256 amount,
                      bytes data
                  );
                  event InboxToggle(address indexed inbox, bool enabled);
                  event OutboxToggle(address indexed outbox, bool enabled);
                  function deliverMessageToInbox(
                      uint8 kind,
                      address sender,
                      bytes32 messageDataHash
                  ) external payable returns (uint256);
                  function executeCall(
                      address destAddr,
                      uint256 amount,
                      bytes calldata data
                  ) external returns (bool success, bytes memory returnData);
                  // These are only callable by the admin
                  function setInbox(address inbox, bool enabled) external;
                  function setOutbox(address inbox, bool enabled) external;
                  // View functions
                  function activeOutbox() external view returns (address);
                  function allowedInboxes(address inbox) external view returns (bool);
                  function allowedOutboxes(address outbox) external view returns (bool);
                  function inboxAccs(uint256 index) external view returns (bytes32);
                  function messageCount() external view returns (uint256);
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "@openzeppelin/contracts/utils/Pausable.sol";
              import "@openzeppelin/contracts/proxy/Proxy.sol";
              import "@openzeppelin/contracts/utils/Address.sol";
              import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
              import "./RollupEventBridge.sol";
              import "./RollupCore.sol";
              import "./RollupLib.sol";
              import "./INode.sol";
              import "./INodeFactory.sol";
              import "../challenge/IChallenge.sol";
              import "../challenge/IChallengeFactory.sol";
              import "../bridge/interfaces/IBridge.sol";
              import "../bridge/interfaces/IOutbox.sol";
              import "../bridge/Messages.sol";
              import "../libraries/ProxyUtil.sol";
              import "../libraries/Cloneable.sol";
              import "./facets/IRollupFacets.sol";
              abstract contract RollupBase is Cloneable, RollupCore, Pausable {
                  // Rollup Config
                  uint256 public confirmPeriodBlocks;
                  uint256 public extraChallengeTimeBlocks;
                  uint256 public avmGasSpeedLimitPerBlock;
                  uint256 public baseStake;
                  // Bridge is an IInbox and IOutbox
                  IBridge public delayedBridge;
                  ISequencerInbox public sequencerBridge;
                  IOutbox public outbox;
                  RollupEventBridge public rollupEventBridge;
                  IChallengeFactory public challengeFactory;
                  INodeFactory public nodeFactory;
                  address public owner;
                  address public stakeToken;
                  uint256 public minimumAssertionPeriod;
                  uint256 public STORAGE_GAP_1;
                  uint256 public STORAGE_GAP_2;
                  uint256 public challengeExecutionBisectionDegree;
                  address[] internal facets;
                  mapping(address => bool) isValidator;
                  /// @notice DEPRECATED -- this method is deprecated but still mantained for backward compatibility
                  /// @dev this actually returns the avmGasSpeedLimitPerBlock
                  /// @return this actually returns the avmGasSpeedLimitPerBlock
                  function arbGasSpeedLimitPerBlock() external view returns (uint256) {
                      return avmGasSpeedLimitPerBlock;
                  }
              }
              contract Rollup is Proxy, RollupBase {
                  using Address for address;
                  constructor(uint256 _confirmPeriodBlocks) public Cloneable() Pausable() {
                      // constructor is used so logic contract can't be init'ed
                      confirmPeriodBlocks = _confirmPeriodBlocks;
                      require(isInit(), "CONSTRUCTOR_NOT_INIT");
                  }
                  function isInit() internal view returns (bool) {
                      return confirmPeriodBlocks != 0;
                  }
                  // _rollupParams = [ confirmPeriodBlocks, extraChallengeTimeBlocks, avmGasSpeedLimitPerBlock, baseStake ]
                  // connectedContracts = [delayedBridge, sequencerInbox, outbox, rollupEventBridge, challengeFactory, nodeFactory]
                  function initialize(
                      bytes32 _machineHash,
                      uint256[4] calldata _rollupParams,
                      address _stakeToken,
                      address _owner,
                      bytes calldata _extraConfig,
                      address[6] calldata connectedContracts,
                      address[2] calldata _facets,
                      uint256[2] calldata sequencerInboxParams
                  ) public {
                      require(!isInit(), "ALREADY_INIT");
                      // calls initialize method in user facet
                      require(_facets[0].isContract(), "FACET_0_NOT_CONTRACT");
                      require(_facets[1].isContract(), "FACET_1_NOT_CONTRACT");
                      (bool success, ) = _facets[1].delegatecall(
                          abi.encodeWithSelector(IRollupUser.initialize.selector, _stakeToken)
                      );
                      require(success, "FAIL_INIT_FACET");
                      delayedBridge = IBridge(connectedContracts[0]);
                      sequencerBridge = ISequencerInbox(connectedContracts[1]);
                      outbox = IOutbox(connectedContracts[2]);
                      delayedBridge.setOutbox(connectedContracts[2], true);
                      rollupEventBridge = RollupEventBridge(connectedContracts[3]);
                      delayedBridge.setInbox(connectedContracts[3], true);
                      rollupEventBridge.rollupInitialized(
                          _rollupParams[0],
                          _rollupParams[2],
                          _owner,
                          _extraConfig
                      );
                      challengeFactory = IChallengeFactory(connectedContracts[4]);
                      nodeFactory = INodeFactory(connectedContracts[5]);
                      INode node = createInitialNode(_machineHash);
                      initializeCore(node);
                      confirmPeriodBlocks = _rollupParams[0];
                      extraChallengeTimeBlocks = _rollupParams[1];
                      avmGasSpeedLimitPerBlock = _rollupParams[2];
                      baseStake = _rollupParams[3];
                      owner = _owner;
                      // A little over 15 minutes
                      minimumAssertionPeriod = 75;
                      challengeExecutionBisectionDegree = 400;
                      sequencerBridge.setMaxDelay(sequencerInboxParams[0], sequencerInboxParams[1]);
                      // facets[0] == admin, facets[1] == user
                      facets = _facets;
                      emit RollupCreated(_machineHash);
                      require(isInit(), "INITIALIZE_NOT_INIT");
                  }
                  function postUpgradeInit() external {
                      // it is assumed the rollup contract is behind a Proxy controlled by a proxy admin
                      // this function can only be called by the proxy admin contract
                      address proxyAdmin = ProxyUtil.getProxyAdmin();
                      require(msg.sender == proxyAdmin, "NOT_FROM_ADMIN");
                      // this upgrade moves the delay blocks and seconds tracking to the sequencer inbox
                      // because of that we need to update the admin facet logic to allow the owner to set
                      // these values in the sequencer inbox
                      STORAGE_GAP_1 = 0;
                      STORAGE_GAP_2 = 0;
                  }
                  function createInitialNode(bytes32 _machineHash) private returns (INode) {
                      bytes32 state = RollupLib.stateHash(
                          RollupLib.ExecutionState(
                              0, // total gas used
                              _machineHash,
                              0, // inbox count
                              0, // send count
                              0, // log count
                              0, // send acc
                              0, // log acc
                              block.number, // block proposed
                              1 // Initialization message already in inbox
                          )
                      );
                      return
                          INode(
                              nodeFactory.createNode(
                                  state,
                                  0, // challenge hash (not challengeable)
                                  0, // confirm data
                                  0, // prev node
                                  block.number // deadline block (not challengeable)
                              )
                          );
                  }
                  /**
                   * This contract uses a dispatch pattern from EIP-2535: Diamonds
                   * together with Open Zeppelin's proxy
                   */
                  function getFacets() external view returns (address, address) {
                      return (getAdminFacet(), getUserFacet());
                  }
                  function getAdminFacet() public view returns (address) {
                      return facets[0];
                  }
                  function getUserFacet() public view returns (address) {
                      return facets[1];
                  }
                  /**
                   * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
                   * and {_fallback} should delegate.
                   */
                  function _implementation() internal view virtual override returns (address) {
                      require(msg.data.length >= 4, "NO_FUNC_SIG");
                      address rollupOwner = owner;
                      // if there is an owner and it is the sender, delegate to admin facet
                      address target = rollupOwner != address(0) && rollupOwner == msg.sender
                          ? getAdminFacet()
                          : getUserFacet();
                      require(target.isContract(), "TARGET_NOT_CONTRACT");
                      return target;
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2019-2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              library Messages {
                  function messageHash(
                      uint8 kind,
                      address sender,
                      uint256 blockNumber,
                      uint256 timestamp,
                      uint256 inboxSeqNum,
                      uint256 gasPriceL1,
                      bytes32 messageDataHash
                  ) internal pure returns (bytes32) {
                      return
                          keccak256(
                              abi.encodePacked(
                                  kind,
                                  sender,
                                  blockNumber,
                                  timestamp,
                                  inboxSeqNum,
                                  gasPriceL1,
                                  messageDataHash
                              )
                          );
                  }
                  function addMessageToInbox(bytes32 inbox, bytes32 message) internal pure returns (bytes32) {
                      return keccak256(abi.encodePacked(inbox, message));
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2019-2020, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "./ICloneable.sol";
              contract Cloneable is ICloneable {
                  string private constant NOT_CLONE = "NOT_CLONE";
                  bool private isMasterCopy;
                  constructor() public {
                      isMasterCopy = true;
                  }
                  function isMaster() external view override returns (bool) {
                      return isMasterCopy;
                  }
                  function safeSelfDestruct(address payable dest) internal {
                      require(!isMasterCopy, NOT_CLONE);
                      selfdestruct(dest);
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              abstract contract WhitelistConsumer {
                  address public whitelist;
                  event WhitelistSourceUpdated(address newSource);
                  modifier onlyWhitelisted() {
                      if (whitelist != address(0)) {
                          require(Whitelist(whitelist).isAllowed(msg.sender), "NOT_WHITELISTED");
                      }
                      _;
                  }
                  function updateWhitelistSource(address newSource) external {
                      require(msg.sender == whitelist, "NOT_FROM_LIST");
                      whitelist = newSource;
                      emit WhitelistSourceUpdated(newSource);
                  }
              }
              contract Whitelist {
                  address public owner;
                  mapping(address => bool) public isAllowed;
                  event OwnerUpdated(address newOwner);
                  event WhitelistUpgraded(address newWhitelist, address[] targets);
                  constructor() public {
                      owner = msg.sender;
                  }
                  modifier onlyOwner() {
                      require(msg.sender == owner, "ONLY_OWNER");
                      _;
                  }
                  function setOwner(address newOwner) external onlyOwner {
                      owner = newOwner;
                      emit OwnerUpdated(newOwner);
                  }
                  function setWhitelist(address[] memory user, bool[] memory val) external onlyOwner {
                      require(user.length == val.length, "INVALID_INPUT");
                      for (uint256 i = 0; i < user.length; i++) {
                          isAllowed[user[i]] = val[i];
                      }
                  }
                  // set new whitelist to address(0) to disable whitelist
                  function triggerConsumers(address newWhitelist, address[] memory targets) external onlyOwner {
                      for (uint256 i = 0; i < targets.length; i++) {
                          WhitelistConsumer(targets[i]).updateWhitelistSource(newWhitelist);
                      }
                      emit WhitelistUpgraded(newWhitelist, targets);
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              library ProxyUtil {
                  function getProxyAdmin() internal view returns (address admin) {
                      // https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v3.4.0/contracts/proxy/TransparentUpgradeableProxy.sol#L48
                      // Storage slot with the admin of the proxy contract.
                      // This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
                      bytes32 slot = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                      assembly {
                          admin := sload(slot)
                      }
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2019-2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              library AddressAliasHelper {
                  uint160 constant offset = uint160(0x1111000000000000000000000000000000001111);
                  /// @notice Utility function that converts the address in the L1 that submitted a tx to
                  /// the inbox to the msg.sender viewed in the L2
                  /// @param l1Address the address in the L1 that triggered the tx to L2
                  /// @return l2Address L2 address as viewed in msg.sender
                  function applyL1ToL2Alias(address l1Address) internal pure returns (address l2Address) {
                      l2Address = address(uint160(l1Address) + offset);
                  }
                  /// @notice Utility function that converts the msg.sender viewed in the L2 to the
                  /// address in the L1 that submitted a tx to the inbox
                  /// @param l2Address L2 address as viewed in msg.sender
                  /// @return l1Address the address in the L1 that triggered the tx to L2
                  function undoL1ToL2Alias(address l2Address) internal pure returns (address l1Address) {
                      l1Address = address(uint160(l2Address) - offset);
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.2 <0.8.0;
              /**
               * @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
                   * ====
                   */
                  function isContract(address account) internal view returns (bool) {
                      // This method relies on extcodesize, which returns 0 for contracts in
                      // construction, since the code is only stored at the end of the
                      // constructor execution.
                      uint256 size;
                      // solhint-disable-next-line no-inline-assembly
                      assembly { size := extcodesize(account) }
                      return size > 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");
                      // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (bool success, bytes memory returndata) = target.delegatecall(data);
                      return _verifyCallResult(success, returndata, errorMessage);
                  }
                  function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private 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
                              // solhint-disable-next-line no-inline-assembly
                              assembly {
                                  let returndata_size := mload(returndata)
                                  revert(add(32, returndata), returndata_size)
                              }
                          } else {
                              revert(errorMessage);
                          }
                      }
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "./Inbox.sol";
              import "./Outbox.sol";
              import "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
              import "@openzeppelin/contracts/utils/Address.sol";
              import "./interfaces/IBridge.sol";
              contract Bridge is OwnableUpgradeable, IBridge {
                  using Address for address;
                  struct InOutInfo {
                      uint256 index;
                      bool allowed;
                  }
                  mapping(address => InOutInfo) private allowedInboxesMap;
                  mapping(address => InOutInfo) private allowedOutboxesMap;
                  address[] public allowedInboxList;
                  address[] public allowedOutboxList;
                  address public override activeOutbox;
                  // Accumulator for delayed inbox; tail represents hash of the current state; each element represents the inclusion of a new message.
                  bytes32[] public override inboxAccs;
                  function initialize() external initializer {
                      __Ownable_init();
                  }
                  function allowedInboxes(address inbox) external view override returns (bool) {
                      return allowedInboxesMap[inbox].allowed;
                  }
                  function allowedOutboxes(address outbox) external view override returns (bool) {
                      return allowedOutboxesMap[outbox].allowed;
                  }
                  function deliverMessageToInbox(
                      uint8 kind,
                      address sender,
                      bytes32 messageDataHash
                  ) external payable override returns (uint256) {
                      require(allowedInboxesMap[msg.sender].allowed, "NOT_FROM_INBOX");
                      return
                          addMessageToInbox(
                              kind,
                              sender,
                              block.number,
                              block.timestamp, // solhint-disable-line not-rely-on-time
                              tx.gasprice,
                              messageDataHash
                          );
                  }
                  function addMessageToInbox(
                      uint8 kind,
                      address sender,
                      uint256 blockNumber,
                      uint256 blockTimestamp,
                      uint256 gasPrice,
                      bytes32 messageDataHash
                  ) internal returns (uint256) {
                      uint256 count = inboxAccs.length;
                      bytes32 messageHash = Messages.messageHash(
                          kind,
                          sender,
                          blockNumber,
                          blockTimestamp,
                          count,
                          gasPrice,
                          messageDataHash
                      );
                      bytes32 prevAcc = 0;
                      if (count > 0) {
                          prevAcc = inboxAccs[count - 1];
                      }
                      inboxAccs.push(Messages.addMessageToInbox(prevAcc, messageHash));
                      emit MessageDelivered(count, prevAcc, msg.sender, kind, sender, messageDataHash);
                      return count;
                  }
                  function executeCall(
                      address destAddr,
                      uint256 amount,
                      bytes calldata data
                  ) external override returns (bool success, bytes memory returnData) {
                      require(allowedOutboxesMap[msg.sender].allowed, "NOT_FROM_OUTBOX");
                      if (data.length > 0) require(destAddr.isContract(), "NO_CODE_AT_DEST");
                      address currentOutbox = activeOutbox;
                      activeOutbox = msg.sender;
                      // We set and reset active outbox around external call so activeOutbox remains valid during call
                      (success, returnData) = destAddr.call{ value: amount }(data);
                      activeOutbox = currentOutbox;
                      emit BridgeCallTriggered(msg.sender, destAddr, amount, data);
                  }
                  function setInbox(address inbox, bool enabled) external override onlyOwner {
                      InOutInfo storage info = allowedInboxesMap[inbox];
                      bool alreadyEnabled = info.allowed;
                      emit InboxToggle(inbox, enabled);
                      if ((alreadyEnabled && enabled) || (!alreadyEnabled && !enabled)) {
                          return;
                      }
                      if (enabled) {
                          allowedInboxesMap[inbox] = InOutInfo(allowedInboxList.length, true);
                          allowedInboxList.push(inbox);
                      } else {
                          allowedInboxList[info.index] = allowedInboxList[allowedInboxList.length - 1];
                          allowedInboxesMap[allowedInboxList[info.index]].index = info.index;
                          allowedInboxList.pop();
                          delete allowedInboxesMap[inbox];
                      }
                  }
                  function setOutbox(address outbox, bool enabled) external override onlyOwner {
                      InOutInfo storage info = allowedOutboxesMap[outbox];
                      bool alreadyEnabled = info.allowed;
                      emit OutboxToggle(outbox, enabled);
                      if ((alreadyEnabled && enabled) || (!alreadyEnabled && !enabled)) {
                          return;
                      }
                      if (enabled) {
                          allowedOutboxesMap[outbox] = InOutInfo(allowedOutboxList.length, true);
                          allowedOutboxList.push(outbox);
                      } else {
                          allowedOutboxList[info.index] = allowedOutboxList[allowedOutboxList.length - 1];
                          allowedOutboxesMap[allowedOutboxList[info.index]].index = info.index;
                          allowedOutboxList.pop();
                          delete allowedOutboxesMap[outbox];
                      }
                  }
                  function messageCount() external view override returns (uint256) {
                      return inboxAccs.length;
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              interface IMessageProvider {
                  event InboxMessageDelivered(uint256 indexed messageNum, bytes data);
                  event InboxMessageDeliveredFromOrigin(uint256 indexed messageNum);
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              import "./Context.sol";
              /**
               * @dev Contract module which allows children to implement an emergency stop
               * mechanism that can be triggered by an authorized account.
               *
               * This module is used through inheritance. It will make available the
               * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
               * the functions of your contract. Note that they will not be pausable by
               * simply including this module, only once the modifiers are put in place.
               */
              abstract contract Pausable is Context {
                  /**
                   * @dev Emitted when the pause is triggered by `account`.
                   */
                  event Paused(address account);
                  /**
                   * @dev Emitted when the pause is lifted by `account`.
                   */
                  event Unpaused(address account);
                  bool private _paused;
                  /**
                   * @dev Initializes the contract in unpaused state.
                   */
                  constructor () internal {
                      _paused = false;
                  }
                  /**
                   * @dev Returns true if the contract is paused, and false otherwise.
                   */
                  function paused() public view virtual returns (bool) {
                      return _paused;
                  }
                  /**
                   * @dev Modifier to make a function callable only when the contract is not paused.
                   *
                   * Requirements:
                   *
                   * - The contract must not be paused.
                   */
                  modifier whenNotPaused() {
                      require(!paused(), "Pausable: paused");
                      _;
                  }
                  /**
                   * @dev Modifier to make a function callable only when the contract is paused.
                   *
                   * Requirements:
                   *
                   * - The contract must be paused.
                   */
                  modifier whenPaused() {
                      require(paused(), "Pausable: not paused");
                      _;
                  }
                  /**
                   * @dev Triggers stopped state.
                   *
                   * Requirements:
                   *
                   * - The contract must not be paused.
                   */
                  function _pause() internal virtual whenNotPaused {
                      _paused = true;
                      emit Paused(_msgSender());
                  }
                  /**
                   * @dev Returns to normal state.
                   *
                   * Requirements:
                   *
                   * - The contract must be paused.
                   */
                  function _unpause() internal virtual whenPaused {
                      _paused = false;
                      emit Unpaused(_msgSender());
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              /**
               * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
               * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
               * be specified by overriding the virtual {_implementation} function.
               *
               * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
               * different contract through the {_delegate} function.
               *
               * The success and return data of the delegated call will be returned back to the caller of the proxy.
               */
              abstract contract Proxy {
                  /**
                   * @dev Delegates the current call to `implementation`.
                   *
                   * This function does not return to its internall call site, it will return directly to the external caller.
                   */
                  function _delegate(address implementation) internal virtual {
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          // Copy msg.data. We take full control of memory in this inline assembly
                          // block because it will not return to Solidity code. We overwrite the
                          // Solidity scratch pad at memory position 0.
                          calldatacopy(0, 0, calldatasize())
                          // Call the implementation.
                          // out and outsize are 0 because we don't know the size yet.
                          let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
                          // Copy the returned data.
                          returndatacopy(0, 0, returndatasize())
                          switch result
                          // delegatecall returns 0 on error.
                          case 0 { revert(0, returndatasize()) }
                          default { return(0, returndatasize()) }
                      }
                  }
                  /**
                   * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
                   * and {_fallback} should delegate.
                   */
                  function _implementation() internal view virtual returns (address);
                  /**
                   * @dev Delegates the current call to the address returned by `_implementation()`.
                   *
                   * This function does not return to its internall call site, it will return directly to the external caller.
                   */
                  function _fallback() internal virtual {
                      _beforeFallback();
                      _delegate(_implementation());
                  }
                  /**
                   * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
                   * function in the contract matches the call data.
                   */
                  fallback () external payable virtual {
                      _fallback();
                  }
                  /**
                   * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
                   * is empty.
                   */
                  receive () external payable virtual {
                      _fallback();
                  }
                  /**
                   * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
                   * call, or as part of the Solidity `fallback` or `receive` functions.
                   *
                   * If overriden should call `super._beforeFallback()`.
                   */
                  function _beforeFallback() internal virtual {
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              /**
               * @dev Interface of the ERC20 standard as defined in the EIP.
               */
              interface IERC20 {
                  /**
                   * @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 `recipient`.
                   *
                   * Returns a boolean value indicating whether the operation succeeded.
                   *
                   * Emits a {Transfer} event.
                   */
                  function transfer(address recipient, 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 `sender` to `recipient` 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 sender, address recipient, uint256 amount) external returns (bool);
                  /**
                   * @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);
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "./Rollup.sol";
              import "./facets/IRollupFacets.sol";
              import "../bridge/interfaces/IBridge.sol";
              import "../bridge/interfaces/IMessageProvider.sol";
              import "./INode.sol";
              import "../libraries/Cloneable.sol";
              contract RollupEventBridge is IMessageProvider, Cloneable {
                  uint8 internal constant INITIALIZATION_MSG_TYPE = 11;
                  uint8 internal constant ROLLUP_PROTOCOL_EVENT_TYPE = 8;
                  uint8 internal constant CREATE_NODE_EVENT = 0;
                  uint8 internal constant CONFIRM_NODE_EVENT = 1;
                  uint8 internal constant REJECT_NODE_EVENT = 2;
                  uint8 internal constant STAKE_CREATED_EVENT = 3;
                  IBridge bridge;
                  address rollup;
                  modifier onlyRollup() {
                      require(msg.sender == rollup, "ONLY_ROLLUP");
                      _;
                  }
                  function initialize(address _bridge, address _rollup) external {
                      require(rollup == address(0), "ALREADY_INIT");
                      bridge = IBridge(_bridge);
                      rollup = _rollup;
                  }
                  function rollupInitialized(
                      uint256 confirmPeriodBlocks,
                      uint256 avmGasSpeedLimitPerBlock,
                      address owner,
                      bytes calldata extraConfig
                  ) external onlyRollup {
                      bytes memory initMsg = abi.encodePacked(
                          keccak256("ChallengePeriodEthBlocks"),
                          confirmPeriodBlocks,
                          keccak256("SpeedLimitPerSecond"),
                          avmGasSpeedLimitPerBlock / 100, // convert avm gas to arbgas
                          keccak256("ChainOwner"),
                          uint256(uint160(bytes20(owner))),
                          extraConfig
                      );
                      uint256 num = bridge.deliverMessageToInbox(
                          INITIALIZATION_MSG_TYPE,
                          address(0),
                          keccak256(initMsg)
                      );
                      emit InboxMessageDelivered(num, initMsg);
                  }
                  function nodeCreated(
                      uint256 nodeNum,
                      uint256 prev,
                      uint256 deadline,
                      address asserter
                  ) external onlyRollup {
                      deliverToBridge(
                          abi.encodePacked(
                              CREATE_NODE_EVENT,
                              nodeNum,
                              prev,
                              block.number,
                              deadline,
                              uint256(uint160(bytes20(asserter)))
                          )
                      );
                  }
                  function nodeConfirmed(uint256 nodeNum) external onlyRollup {
                      deliverToBridge(abi.encodePacked(CONFIRM_NODE_EVENT, nodeNum));
                  }
                  function nodeRejected(uint256 nodeNum) external onlyRollup {
                      deliverToBridge(abi.encodePacked(REJECT_NODE_EVENT, nodeNum));
                  }
                  function stakeCreated(address staker, uint256 nodeNum) external onlyRollup {
                      deliverToBridge(
                          abi.encodePacked(
                              STAKE_CREATED_EVENT,
                              uint256(uint160(bytes20(staker))),
                              nodeNum,
                              block.number
                          )
                      );
                  }
                  function deliverToBridge(bytes memory message) private {
                      emit InboxMessageDelivered(
                          bridge.deliverMessageToInbox(
                              ROLLUP_PROTOCOL_EVENT_TYPE,
                              msg.sender,
                              keccak256(message)
                          ),
                          message
                      );
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "./INode.sol";
              import "./IRollupCore.sol";
              import "./RollupLib.sol";
              import "./INodeFactory.sol";
              import "./RollupEventBridge.sol";
              import "../bridge/interfaces/ISequencerInbox.sol";
              import "@openzeppelin/contracts/math/SafeMath.sol";
              contract RollupCore is IRollupCore {
                  using SafeMath for uint256;
                  // Stakers become Zombies after losing a challenge
                  struct Zombie {
                      address stakerAddress;
                      uint256 latestStakedNode;
                  }
                  struct Staker {
                      uint256 index;
                      uint256 latestStakedNode;
                      uint256 amountStaked;
                      // currentChallenge is 0 if staker is not in a challenge
                      address currentChallenge;
                      bool isStaked;
                  }
                  uint256 private _latestConfirmed;
                  uint256 private _firstUnresolvedNode;
                  uint256 private _latestNodeCreated;
                  uint256 private _lastStakeBlock;
                  mapping(uint256 => INode) private _nodes;
                  mapping(uint256 => bytes32) private _nodeHashes;
                  address payable[] private _stakerList;
                  mapping(address => Staker) public override _stakerMap;
                  Zombie[] private _zombies;
                  mapping(address => uint256) private _withdrawableFunds;
                  /**
                   * @notice Get the address of the Node contract for the given node
                   * @param nodeNum Index of the node
                   * @return Address of the Node contract
                   */
                  function getNode(uint256 nodeNum) public view override returns (INode) {
                      return _nodes[nodeNum];
                  }
                  /**
                   * @notice Get the address of the staker at the given index
                   * @param stakerNum Index of the staker
                   * @return Address of the staker
                   */
                  function getStakerAddress(uint256 stakerNum) external view override returns (address) {
                      return _stakerList[stakerNum];
                  }
                  /**
                   * @notice Check whether the given staker is staked
                   * @param staker Staker address to check
                   * @return True or False for whether the staker was staked
                   */
                  function isStaked(address staker) public view override returns (bool) {
                      return _stakerMap[staker].isStaked;
                  }
                  /**
                   * @notice Get the latest staked node of the given staker
                   * @param staker Staker address to lookup
                   * @return Latest node staked of the staker
                   */
                  function latestStakedNode(address staker) public view override returns (uint256) {
                      return _stakerMap[staker].latestStakedNode;
                  }
                  /**
                   * @notice Get the current challenge of the given staker
                   * @param staker Staker address to lookup
                   * @return Current challenge of the staker
                   */
                  function currentChallenge(address staker) public view override returns (address) {
                      return _stakerMap[staker].currentChallenge;
                  }
                  /**
                   * @notice Get the amount staked of the given staker
                   * @param staker Staker address to lookup
                   * @return Amount staked of the staker
                   */
                  function amountStaked(address staker) public view override returns (uint256) {
                      return _stakerMap[staker].amountStaked;
                  }
                  /**
                   * @notice Get the original staker address of the zombie at the given index
                   * @param zombieNum Index of the zombie to lookup
                   * @return Original staker address of the zombie
                   */
                  function zombieAddress(uint256 zombieNum) public view override returns (address) {
                      return _zombies[zombieNum].stakerAddress;
                  }
                  /**
                   * @notice Get Latest node that the given zombie at the given index is staked on
                   * @param zombieNum Index of the zombie to lookup
                   * @return Latest node that the given zombie is staked on
                   */
                  function zombieLatestStakedNode(uint256 zombieNum) public view override returns (uint256) {
                      return _zombies[zombieNum].latestStakedNode;
                  }
                  /// @return Current number of un-removed zombies
                  function zombieCount() public view override returns (uint256) {
                      return _zombies.length;
                  }
                  function isZombie(address staker) public view override returns (bool) {
                      for (uint256 i = 0; i < _zombies.length; i++) {
                          if (staker == _zombies[i].stakerAddress) {
                              return true;
                          }
                      }
                      return false;
                  }
                  /**
                   * @notice Get the amount of funds withdrawable by the given address
                   * @param owner Address to check the funds of
                   * @return Amount of funds withdrawable by owner
                   */
                  function withdrawableFunds(address owner) external view override returns (uint256) {
                      return _withdrawableFunds[owner];
                  }
                  /**
                   * @return Index of the first unresolved node
                   * @dev If all nodes have been resolved, this will be latestNodeCreated + 1
                   */
                  function firstUnresolvedNode() public view override returns (uint256) {
                      return _firstUnresolvedNode;
                  }
                  /// @return Index of the latest confirmed node
                  function latestConfirmed() public view override returns (uint256) {
                      return _latestConfirmed;
                  }
                  /// @return Index of the latest rollup node created
                  function latestNodeCreated() public view override returns (uint256) {
                      return _latestNodeCreated;
                  }
                  /// @return Ethereum block that the most recent stake was created
                  function lastStakeBlock() external view override returns (uint256) {
                      return _lastStakeBlock;
                  }
                  /// @return Number of active stakers currently staked
                  function stakerCount() public view override returns (uint256) {
                      return _stakerList.length;
                  }
                  /**
                   * @notice Initialize the core with an initial node
                   * @param initialNode Initial node to start the chain with
                   */
                  function initializeCore(INode initialNode) internal {
                      _nodes[0] = initialNode;
                      _firstUnresolvedNode = 1;
                  }
                  /**
                   * @notice React to a new node being created by storing it an incrementing the latest node counter
                   * @param node Node that was newly created
                   * @param nodeHash The hash of said node
                   */
                  function nodeCreated(INode node, bytes32 nodeHash) internal {
                      _latestNodeCreated++;
                      _nodes[_latestNodeCreated] = node;
                      _nodeHashes[_latestNodeCreated] = nodeHash;
                  }
                  /// @return Node hash as of this node number
                  function getNodeHash(uint256 index) public view override returns (bytes32) {
                      return _nodeHashes[index];
                  }
                  /// @notice Reject the next unresolved node
                  function _rejectNextNode() internal {
                      destroyNode(_firstUnresolvedNode);
                      _firstUnresolvedNode++;
                  }
                  /// @notice Confirm the next unresolved node
                  function confirmNextNode(
                      bytes32 beforeSendAcc,
                      bytes calldata sendsData,
                      uint256[] calldata sendLengths,
                      uint256 afterSendCount,
                      bytes32 afterLogAcc,
                      uint256 afterLogCount,
                      IOutbox outbox,
                      RollupEventBridge rollupEventBridge
                  ) internal {
                      confirmNode(
                          _firstUnresolvedNode,
                          beforeSendAcc,
                          sendsData,
                          sendLengths,
                          afterSendCount,
                          afterLogAcc,
                          afterLogCount,
                          outbox,
                          rollupEventBridge
                      );
                  }
                  function confirmNode(
                      uint256 nodeNum,
                      bytes32 beforeSendAcc,
                      bytes calldata sendsData,
                      uint256[] calldata sendLengths,
                      uint256 afterSendCount,
                      bytes32 afterLogAcc,
                      uint256 afterLogCount,
                      IOutbox outbox,
                      RollupEventBridge rollupEventBridge
                  ) internal {
                      bytes32 afterSendAcc = RollupLib.feedAccumulator(sendsData, sendLengths, beforeSendAcc);
                      INode node = getNode(nodeNum);
                      // Authenticate data against node's confirm data pre-image
                      require(
                          node.confirmData() ==
                              RollupLib.confirmHash(
                                  beforeSendAcc,
                                  afterSendAcc,
                                  afterLogAcc,
                                  afterSendCount,
                                  afterLogCount
                              ),
                          "CONFIRM_DATA"
                      );
                      // trusted external call to outbox
                      outbox.processOutgoingMessages(sendsData, sendLengths);
                      destroyNode(_latestConfirmed);
                      _latestConfirmed = nodeNum;
                      _firstUnresolvedNode = nodeNum + 1;
                      rollupEventBridge.nodeConfirmed(nodeNum);
                      emit NodeConfirmed(nodeNum, afterSendAcc, afterSendCount, afterLogAcc, afterLogCount);
                  }
                  /**
                   * @notice Create a new stake at latest confirmed node
                   * @param stakerAddress Address of the new staker
                   * @param depositAmount Stake amount of the new staker
                   */
                  function createNewStake(address payable stakerAddress, uint256 depositAmount) internal {
                      uint256 stakerIndex = _stakerList.length;
                      _stakerList.push(stakerAddress);
                      _stakerMap[stakerAddress] = Staker(
                          stakerIndex,
                          _latestConfirmed,
                          depositAmount,
                          address(0), // new staker is not in challenge
                          true
                      );
                      _lastStakeBlock = block.number;
                      emit UserStakeUpdated(stakerAddress, 0, depositAmount);
                  }
                  /**
                   * @notice Check to see whether the two stakers are in the same challenge
                   * @param stakerAddress1 Address of the first staker
                   * @param stakerAddress2 Address of the second staker
                   * @return Address of the challenge that the two stakers are in
                   */
                  function inChallenge(address stakerAddress1, address stakerAddress2)
                      internal
                      view
                      returns (address)
                  {
                      Staker storage staker1 = _stakerMap[stakerAddress1];
                      Staker storage staker2 = _stakerMap[stakerAddress2];
                      address challenge = staker1.currentChallenge;
                      require(challenge != address(0), "NO_CHAL");
                      require(challenge == staker2.currentChallenge, "DIFF_IN_CHAL");
                      return challenge;
                  }
                  /**
                   * @notice Make the given staker as not being in a challenge
                   * @param stakerAddress Address of the staker to remove from a challenge
                   */
                  function clearChallenge(address stakerAddress) internal {
                      Staker storage staker = _stakerMap[stakerAddress];
                      staker.currentChallenge = address(0);
                  }
                  /**
                   * @notice Mark both the given stakers as engaged in the challenge
                   * @param staker1 Address of the first staker
                   * @param staker2 Address of the second staker
                   * @param challenge Address of the challenge both stakers are now in
                   */
                  function challengeStarted(
                      address staker1,
                      address staker2,
                      address challenge
                  ) internal {
                      _stakerMap[staker1].currentChallenge = challenge;
                      _stakerMap[staker2].currentChallenge = challenge;
                  }
                  /**
                   * @notice Add to the stake of the given staker by the given amount
                   * @param stakerAddress Address of the staker to increase the stake of
                   * @param amountAdded Amount of stake to add to the staker
                   */
                  function increaseStakeBy(address stakerAddress, uint256 amountAdded) internal {
                      Staker storage staker = _stakerMap[stakerAddress];
                      uint256 initialStaked = staker.amountStaked;
                      uint256 finalStaked = initialStaked.add(amountAdded);
                      staker.amountStaked = finalStaked;
                      emit UserStakeUpdated(stakerAddress, initialStaked, finalStaked);
                  }
                  /**
                   * @notice Reduce the stake of the given staker to the given target
                   * @param stakerAddress Address of the staker to reduce the stake of
                   * @param target Amount of stake to leave with the staker
                   * @return Amount of value released from the stake
                   */
                  function reduceStakeTo(address stakerAddress, uint256 target) internal returns (uint256) {
                      Staker storage staker = _stakerMap[stakerAddress];
                      uint256 current = staker.amountStaked;
                      require(target <= current, "TOO_LITTLE_STAKE");
                      uint256 amountWithdrawn = current.sub(target);
                      staker.amountStaked = target;
                      increaseWithdrawableFunds(stakerAddress, amountWithdrawn);
                      emit UserStakeUpdated(stakerAddress, current, target);
                      return amountWithdrawn;
                  }
                  /**
                   * @notice Remove the given staker and turn them into a zombie
                   * @param stakerAddress Address of the staker to remove
                   */
                  function turnIntoZombie(address stakerAddress) internal {
                      Staker storage staker = _stakerMap[stakerAddress];
                      _zombies.push(Zombie(stakerAddress, staker.latestStakedNode));
                      deleteStaker(stakerAddress);
                  }
                  /**
                   * @notice Update the latest staked node of the zombie at the given index
                   * @param zombieNum Index of the zombie to move
                   * @param latest New latest node the zombie is staked on
                   */
                  function zombieUpdateLatestStakedNode(uint256 zombieNum, uint256 latest) internal {
                      _zombies[zombieNum].latestStakedNode = latest;
                  }
                  /**
                   * @notice Remove the zombie at the given index
                   * @param zombieNum Index of the zombie to remove
                   */
                  function removeZombie(uint256 zombieNum) internal {
                      _zombies[zombieNum] = _zombies[_zombies.length - 1];
                      _zombies.pop();
                  }
                  /**
                   * @notice Remove the given staker and return their stake
                   * @param stakerAddress Address of the staker withdrawing their stake
                   */
                  function withdrawStaker(address stakerAddress) internal {
                      Staker storage staker = _stakerMap[stakerAddress];
                      uint256 initialStaked = staker.amountStaked;
                      increaseWithdrawableFunds(stakerAddress, initialStaked);
                      deleteStaker(stakerAddress);
                      emit UserStakeUpdated(stakerAddress, initialStaked, 0);
                  }
                  /**
                   * @notice Advance the given staker to the given node
                   * @param stakerAddress Address of the staker adding their stake
                   * @param nodeNum Index of the node to stake on
                   */
                  function stakeOnNode(
                      address stakerAddress,
                      uint256 nodeNum,
                      uint256 confirmPeriodBlocks
                  ) internal {
                      Staker storage staker = _stakerMap[stakerAddress];
                      INode node = _nodes[nodeNum];
                      uint256 newStakerCount = node.addStaker(stakerAddress);
                      staker.latestStakedNode = nodeNum;
                      if (newStakerCount == 1) {
                          INode parent = _nodes[node.prev()];
                          parent.newChildConfirmDeadline(block.number.add(confirmPeriodBlocks));
                      }
                  }
                  /**
                   * @notice Clear the withdrawable funds for the given address
                   * @param owner Address of the account to remove funds from
                   * @return Amount of funds removed from account
                   */
                  function withdrawFunds(address owner) internal returns (uint256) {
                      uint256 amount = _withdrawableFunds[owner];
                      _withdrawableFunds[owner] = 0;
                      emit UserWithdrawableFundsUpdated(owner, amount, 0);
                      return amount;
                  }
                  /**
                   * @notice Increase the withdrawable funds for the given address
                   * @param owner Address of the account to add withdrawable funds to
                   */
                  function increaseWithdrawableFunds(address owner, uint256 amount) internal {
                      uint256 initialWithdrawable = _withdrawableFunds[owner];
                      uint256 finalWithdrawable = initialWithdrawable.add(amount);
                      _withdrawableFunds[owner] = finalWithdrawable;
                      emit UserWithdrawableFundsUpdated(owner, initialWithdrawable, finalWithdrawable);
                  }
                  /**
                   * @notice Remove the given staker
                   * @param stakerAddress Address of the staker to remove
                   */
                  function deleteStaker(address stakerAddress) private {
                      Staker storage staker = _stakerMap[stakerAddress];
                      uint256 stakerIndex = staker.index;
                      _stakerList[stakerIndex] = _stakerList[_stakerList.length - 1];
                      _stakerMap[_stakerList[stakerIndex]].index = stakerIndex;
                      _stakerList.pop();
                      delete _stakerMap[stakerAddress];
                  }
                  /**
                   * @notice Destroy the given node and clear out its address
                   * @param nodeNum Index of the node to remove
                   */
                  function destroyNode(uint256 nodeNum) internal {
                      _nodes[nodeNum].destroy();
                      _nodes[nodeNum] = INode(0);
                  }
                  function nodeDeadline(
                      uint256 avmGasSpeedLimitPerBlock,
                      uint256 gasUsed,
                      uint256 confirmPeriodBlocks,
                      INode prevNode
                  ) internal view returns (uint256 deadlineBlock) {
                      // Set deadline rounding up to the nearest block
                      uint256 checkTime = gasUsed.add(avmGasSpeedLimitPerBlock.sub(1)).div(
                          avmGasSpeedLimitPerBlock
                      );
                      deadlineBlock = max(block.number.add(confirmPeriodBlocks), prevNode.deadlineBlock()).add(
                          checkTime
                      );
                      uint256 olderSibling = prevNode.latestChildNumber();
                      if (olderSibling != 0) {
                          deadlineBlock = max(deadlineBlock, getNode(olderSibling).deadlineBlock());
                      }
                      return deadlineBlock;
                  }
                  function max(uint256 a, uint256 b) internal pure returns (uint256) {
                      return a > b ? a : b;
                  }
                  struct StakeOnNewNodeFrame {
                      uint256 currentInboxSize;
                      INode node;
                      bytes32 executionHash;
                      INode prevNode;
                      bytes32 lastHash;
                      bool hasSibling;
                      uint256 deadlineBlock;
                      uint256 gasUsed;
                      uint256 sequencerBatchEnd;
                      bytes32 sequencerBatchAcc;
                  }
                  struct CreateNodeDataFrame {
                      uint256 prevNode;
                      uint256 confirmPeriodBlocks;
                      uint256 avmGasSpeedLimitPerBlock;
                      ISequencerInbox sequencerInbox;
                      RollupEventBridge rollupEventBridge;
                      INodeFactory nodeFactory;
                  }
                  uint8 internal constant MAX_SEND_COUNT = 100;
                  function createNewNode(
                      RollupLib.Assertion memory assertion,
                      bytes32[3][2] calldata assertionBytes32Fields,
                      uint256[4][2] calldata assertionIntFields,
                      bytes calldata sequencerBatchProof,
                      CreateNodeDataFrame memory inputDataFrame,
                      bytes32 expectedNodeHash
                  ) internal returns (bytes32 newNodeHash) {
                      StakeOnNewNodeFrame memory memoryFrame;
                      {
                          // validate data
                          memoryFrame.gasUsed = RollupLib.assertionGasUsed(assertion);
                          memoryFrame.prevNode = getNode(inputDataFrame.prevNode);
                          memoryFrame.currentInboxSize = inputDataFrame.sequencerInbox.messageCount();
                          // Make sure the previous state is correct against the node being built on
                          require(
                              RollupLib.stateHash(assertion.beforeState) == memoryFrame.prevNode.stateHash(),
                              "PREV_STATE_HASH"
                          );
                          // Ensure that the assertion doesn't read past the end of the current inbox
                          require(
                              assertion.afterState.inboxCount <= memoryFrame.currentInboxSize,
                              "INBOX_PAST_END"
                          );
                          // Insure inbox tip after assertion is included in a sequencer-inbox batch and return inbox acc; this gives replay protection against the state of the inbox
                          (memoryFrame.sequencerBatchEnd, memoryFrame.sequencerBatchAcc) = inputDataFrame
                              .sequencerInbox
                              .proveInboxContainsMessage(sequencerBatchProof, assertion.afterState.inboxCount);
                      }
                      {
                          memoryFrame.executionHash = RollupLib.executionHash(assertion);
                          memoryFrame.deadlineBlock = nodeDeadline(
                              inputDataFrame.avmGasSpeedLimitPerBlock,
                              memoryFrame.gasUsed,
                              inputDataFrame.confirmPeriodBlocks,
                              memoryFrame.prevNode
                          );
                          memoryFrame.hasSibling = memoryFrame.prevNode.latestChildNumber() > 0;
                          // here we don't use ternacy operator to remain compatible with slither
                          if (memoryFrame.hasSibling) {
                              memoryFrame.lastHash = getNodeHash(memoryFrame.prevNode.latestChildNumber());
                          } else {
                              memoryFrame.lastHash = getNodeHash(inputDataFrame.prevNode);
                          }
                          memoryFrame.node = INode(
                              inputDataFrame.nodeFactory.createNode(
                                  RollupLib.stateHash(assertion.afterState),
                                  RollupLib.challengeRoot(assertion, memoryFrame.executionHash, block.number),
                                  RollupLib.confirmHash(assertion),
                                  inputDataFrame.prevNode,
                                  memoryFrame.deadlineBlock
                              )
                          );
                      }
                      {
                          uint256 nodeNum = latestNodeCreated() + 1;
                          memoryFrame.prevNode.childCreated(nodeNum);
                          newNodeHash = RollupLib.nodeHash(
                              memoryFrame.hasSibling,
                              memoryFrame.lastHash,
                              memoryFrame.executionHash,
                              memoryFrame.sequencerBatchAcc
                          );
                          require(newNodeHash == expectedNodeHash, "UNEXPECTED_NODE_HASH");
                          nodeCreated(memoryFrame.node, newNodeHash);
                          inputDataFrame.rollupEventBridge.nodeCreated(
                              nodeNum,
                              inputDataFrame.prevNode,
                              memoryFrame.deadlineBlock,
                              msg.sender
                          );
                      }
                      emit NodeCreated(
                          latestNodeCreated(),
                          getNodeHash(inputDataFrame.prevNode),
                          newNodeHash,
                          memoryFrame.executionHash,
                          memoryFrame.currentInboxSize,
                          memoryFrame.sequencerBatchEnd,
                          memoryFrame.sequencerBatchAcc,
                          assertionBytes32Fields,
                          assertionIntFields
                      );
                      return newNodeHash;
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "../challenge/ChallengeLib.sol";
              import "./INode.sol";
              import "@openzeppelin/contracts/math/SafeMath.sol";
              library RollupLib {
                  using SafeMath for uint256;
                  struct Config {
                      bytes32 machineHash;
                      uint256 confirmPeriodBlocks;
                      uint256 extraChallengeTimeBlocks;
                      uint256 avmGasSpeedLimitPerBlock;
                      uint256 baseStake;
                      address stakeToken;
                      address owner;
                      address sequencer;
                      uint256 sequencerDelayBlocks;
                      uint256 sequencerDelaySeconds;
                      bytes extraConfig;
                  }
                  struct ExecutionState {
                      uint256 gasUsed;
                      bytes32 machineHash;
                      uint256 inboxCount;
                      uint256 sendCount;
                      uint256 logCount;
                      bytes32 sendAcc;
                      bytes32 logAcc;
                      uint256 proposedBlock;
                      uint256 inboxMaxCount;
                  }
                  function stateHash(ExecutionState memory execState) internal pure returns (bytes32) {
                      return
                          keccak256(
                              abi.encodePacked(
                                  execState.gasUsed,
                                  execState.machineHash,
                                  execState.inboxCount,
                                  execState.sendCount,
                                  execState.logCount,
                                  execState.sendAcc,
                                  execState.logAcc,
                                  execState.proposedBlock,
                                  execState.inboxMaxCount
                              )
                          );
                  }
                  struct Assertion {
                      ExecutionState beforeState;
                      ExecutionState afterState;
                  }
                  function decodeExecutionState(
                      bytes32[3] memory bytes32Fields,
                      uint256[4] memory intFields,
                      uint256 proposedBlock,
                      uint256 inboxMaxCount
                  ) internal pure returns (ExecutionState memory) {
                      return
                          ExecutionState(
                              intFields[0],
                              bytes32Fields[0],
                              intFields[1],
                              intFields[2],
                              intFields[3],
                              bytes32Fields[1],
                              bytes32Fields[2],
                              proposedBlock,
                              inboxMaxCount
                          );
                  }
                  function decodeAssertion(
                      bytes32[3][2] memory bytes32Fields,
                      uint256[4][2] memory intFields,
                      uint256 beforeProposedBlock,
                      uint256 beforeInboxMaxCount,
                      uint256 inboxMaxCount
                  ) internal view returns (Assertion memory) {
                      return
                          Assertion(
                              decodeExecutionState(
                                  bytes32Fields[0],
                                  intFields[0],
                                  beforeProposedBlock,
                                  beforeInboxMaxCount
                              ),
                              decodeExecutionState(bytes32Fields[1], intFields[1], block.number, inboxMaxCount)
                          );
                  }
                  function executionStateChallengeHash(ExecutionState memory state)
                      internal
                      pure
                      returns (bytes32)
                  {
                      return
                          ChallengeLib.assertionHash(
                              state.gasUsed,
                              ChallengeLib.assertionRestHash(
                                  state.inboxCount,
                                  state.machineHash,
                                  state.sendAcc,
                                  state.sendCount,
                                  state.logAcc,
                                  state.logCount
                              )
                          );
                  }
                  function executionHash(Assertion memory assertion) internal pure returns (bytes32) {
                      return
                          ChallengeLib.bisectionChunkHash(
                              assertion.beforeState.gasUsed,
                              assertion.afterState.gasUsed - assertion.beforeState.gasUsed,
                              RollupLib.executionStateChallengeHash(assertion.beforeState),
                              RollupLib.executionStateChallengeHash(assertion.afterState)
                          );
                  }
                  function assertionGasUsed(RollupLib.Assertion memory assertion)
                      internal
                      pure
                      returns (uint256)
                  {
                      return assertion.afterState.gasUsed.sub(assertion.beforeState.gasUsed);
                  }
                  function challengeRoot(
                      Assertion memory assertion,
                      bytes32 assertionExecHash,
                      uint256 blockProposed
                  ) internal pure returns (bytes32) {
                      return challengeRootHash(assertionExecHash, blockProposed, assertion.afterState.inboxCount);
                  }
                  function challengeRootHash(
                      bytes32 execution,
                      uint256 proposedTime,
                      uint256 maxMessageCount
                  ) internal pure returns (bytes32) {
                      return keccak256(abi.encodePacked(execution, proposedTime, maxMessageCount));
                  }
                  function confirmHash(Assertion memory assertion) internal pure returns (bytes32) {
                      return
                          confirmHash(
                              assertion.beforeState.sendAcc,
                              assertion.afterState.sendAcc,
                              assertion.afterState.logAcc,
                              assertion.afterState.sendCount,
                              assertion.afterState.logCount
                          );
                  }
                  function confirmHash(
                      bytes32 beforeSendAcc,
                      bytes32 afterSendAcc,
                      bytes32 afterLogAcc,
                      uint256 afterSendCount,
                      uint256 afterLogCount
                  ) internal pure returns (bytes32) {
                      return
                          keccak256(
                              abi.encodePacked(
                                  beforeSendAcc,
                                  afterSendAcc,
                                  afterSendCount,
                                  afterLogAcc,
                                  afterLogCount
                              )
                          );
                  }
                  function feedAccumulator(
                      bytes memory messageData,
                      uint256[] memory messageLengths,
                      bytes32 beforeAcc
                  ) internal pure returns (bytes32) {
                      uint256 offset = 0;
                      uint256 messageCount = messageLengths.length;
                      uint256 dataLength = messageData.length;
                      bytes32 messageAcc = beforeAcc;
                      for (uint256 i = 0; i < messageCount; i++) {
                          uint256 messageLength = messageLengths[i];
                          require(offset + messageLength <= dataLength, "DATA_OVERRUN");
                          bytes32 messageHash;
                          assembly {
                              messageHash := keccak256(add(messageData, add(offset, 32)), messageLength)
                          }
                          messageAcc = keccak256(abi.encodePacked(messageAcc, messageHash));
                          offset += messageLength;
                      }
                      require(offset == dataLength, "DATA_LENGTH");
                      return messageAcc;
                  }
                  function nodeHash(
                      bool hasSibling,
                      bytes32 lastHash,
                      bytes32 assertionExecHash,
                      bytes32 inboxAcc
                  ) internal pure returns (bytes32) {
                      uint8 hasSiblingInt = hasSibling ? 1 : 0;
                      return keccak256(abi.encodePacked(hasSiblingInt, lastHash, assertionExecHash, inboxAcc));
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              interface INode {
                  function initialize(
                      address _rollup,
                      bytes32 _stateHash,
                      bytes32 _challengeHash,
                      bytes32 _confirmData,
                      uint256 _prev,
                      uint256 _deadlineBlock
                  ) external;
                  function destroy() external;
                  function addStaker(address staker) external returns (uint256);
                  function removeStaker(address staker) external;
                  function childCreated(uint256) external;
                  function newChildConfirmDeadline(uint256 deadline) external;
                  function stateHash() external view returns (bytes32);
                  function challengeHash() external view returns (bytes32);
                  function confirmData() external view returns (bytes32);
                  function prev() external view returns (uint256);
                  function deadlineBlock() external view returns (uint256);
                  function noChildConfirmedBeforeBlock() external view returns (uint256);
                  function stakerCount() external view returns (uint256);
                  function stakers(address staker) external view returns (bool);
                  function firstChildBlock() external view returns (uint256);
                  function latestChildNumber() external view returns (uint256);
                  function requirePastDeadline() external view;
                  function requirePastChildConfirmDeadline() external view;
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              interface INodeFactory {
                  function createNode(
                      bytes32 _stateHash,
                      bytes32 _challengeHash,
                      bytes32 _confirmData,
                      uint256 _prev,
                      uint256 _deadlineBlock
                  ) external returns (address);
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "../bridge/interfaces/IBridge.sol";
              import "../bridge/interfaces/ISequencerInbox.sol";
              import "../arch/IOneStepProof.sol";
              interface IChallenge {
                  function initializeChallenge(
                      IOneStepProof[] calldata _executors,
                      address _resultReceiver,
                      bytes32 _executionHash,
                      uint256 _maxMessageCount,
                      address _asserter,
                      address _challenger,
                      uint256 _asserterTimeLeft,
                      uint256 _challengerTimeLeft,
                      ISequencerInbox _sequencerBridge,
                      IBridge _delayedBridge
                  ) external;
                  function currentResponderTimeLeft() external view returns (uint256);
                  function lastMoveBlock() external view returns (uint256);
                  function timeout() external;
                  function asserter() external view returns (address);
                  function challenger() external view returns (address);
                  function clearChallenge() external;
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2019-2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "../bridge/interfaces/IBridge.sol";
              import "../bridge/interfaces/ISequencerInbox.sol";
              interface IChallengeFactory {
                  function createChallenge(
                      address _resultReceiver,
                      bytes32 _executionHash,
                      uint256 _maxMessageCount,
                      address _asserter,
                      address _challenger,
                      uint256 _asserterTimeLeft,
                      uint256 _challengerTimeLeft,
                      ISequencerInbox _sequencerBridge,
                      IBridge _delayedBridge
                  ) external returns (address);
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              interface IOutbox {
                  event OutboxEntryCreated(
                      uint256 indexed batchNum,
                      uint256 outboxEntryIndex,
                      bytes32 outputRoot,
                      uint256 numInBatch
                  );
                  event OutBoxTransactionExecuted(
                      address indexed destAddr,
                      address indexed l2Sender,
                      uint256 indexed outboxEntryIndex,
                      uint256 transactionIndex
                  );
                  function l2ToL1Sender() external view returns (address);
                  function l2ToL1Block() external view returns (uint256);
                  function l2ToL1EthBlock() external view returns (uint256);
                  function l2ToL1Timestamp() external view returns (uint256);
                  function l2ToL1BatchNum() external view returns (uint256);
                  function l2ToL1OutputId() external view returns (bytes32);
                  function processOutgoingMessages(bytes calldata sendsData, uint256[] calldata sendLengths)
                      external;
                  function outboxEntryExists(uint256 batchNum) external view returns (bool);
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "../INode.sol";
              import "../../bridge/interfaces/IOutbox.sol";
              interface IRollupUser {
                  function initialize(address _stakeToken) external;
                  function completeChallenge(address winningStaker, address losingStaker) external;
                  function returnOldDeposit(address stakerAddress) external;
                  function requireUnresolved(uint256 nodeNum) external view;
                  function requireUnresolvedExists() external view;
                  function countStakedZombies(INode node) external view returns (uint256);
              }
              interface IRollupAdmin {
                  event OwnerFunctionCalled(uint256 indexed id);
                  /**
                   * @notice Add a contract authorized to put messages into this rollup's inbox
                   * @param _outbox Outbox contract to add
                   */
                  function setOutbox(IOutbox _outbox) external;
                  /**
                   * @notice Disable an old outbox from interacting with the bridge
                   * @param _outbox Outbox contract to remove
                   */
                  function removeOldOutbox(address _outbox) external;
                  /**
                   * @notice Enable or disable an inbox contract
                   * @param _inbox Inbox contract to add or remove
                   * @param _enabled New status of inbox
                   */
                  function setInbox(address _inbox, bool _enabled) external;
                  /**
                   * @notice Pause interaction with the rollup contract
                   */
                  function pause() external;
                  /**
                   * @notice Resume interaction with the rollup contract
                   */
                  function resume() external;
                  /**
                   * @notice Set the addresses of rollup logic facets called
                   * @param newAdminFacet address of logic that owner of rollup calls
                   * @param newUserFacet ddress of logic that user of rollup calls
                   */
                  function setFacets(address newAdminFacet, address newUserFacet) external;
                  /**
                   * @notice Set the addresses of the validator whitelist
                   * @dev It is expected that both arrays are same length, and validator at
                   * position i corresponds to the value at position i
                   * @param _validator addresses to set in the whitelist
                   * @param _val value to set in the whitelist for corresponding address
                   */
                  function setValidator(address[] memory _validator, bool[] memory _val) external;
                  /**
                   * @notice Set a new owner address for the rollup
                   * @param newOwner address of new rollup owner
                   */
                  function setOwner(address newOwner) external;
                  /**
                   * @notice Set minimum assertion period for the rollup
                   * @param newPeriod new minimum period for assertions
                   */
                  function setMinimumAssertionPeriod(uint256 newPeriod) external;
                  /**
                   * @notice Set number of blocks until a node is considered confirmed
                   * @param newConfirmPeriod new number of blocks until a node is confirmed
                   */
                  function setConfirmPeriodBlocks(uint256 newConfirmPeriod) external;
                  /**
                   * @notice Set number of extra blocks after a challenge
                   * @param newExtraTimeBlocks new number of blocks
                   */
                  function setExtraChallengeTimeBlocks(uint256 newExtraTimeBlocks) external;
                  /**
                   * @notice Set speed limit per block
                   * @param newAvmGasSpeedLimitPerBlock maximum avmgas to be used per block
                   */
                  function setAvmGasSpeedLimitPerBlock(uint256 newAvmGasSpeedLimitPerBlock) external;
                  /**
                   * @notice Set base stake required for an assertion
                   * @param newBaseStake maximum avmgas to be used per block
                   */
                  function setBaseStake(uint256 newBaseStake) external;
                  /**
                   * @notice Set the token used for stake, where address(0) == eth
                   * @dev Before changing the base stake token, you might need to change the
                   * implementation of the Rollup User facet!
                   * @param newStakeToken address of token used for staking
                   */
                  function setStakeToken(address newStakeToken) external;
                  /**
                   * @notice Set max delay for sequencer inbox
                   * @param newSequencerInboxMaxDelayBlocks max number of blocks
                   * @param newSequencerInboxMaxDelaySeconds max number of seconds
                   */
                  function setSequencerInboxMaxDelay(
                      uint256 newSequencerInboxMaxDelayBlocks,
                      uint256 newSequencerInboxMaxDelaySeconds
                  ) external;
                  /**
                   * @notice Set execution bisection degree
                   * @param newChallengeExecutionBisectionDegree execution bisection degree
                   */
                  function setChallengeExecutionBisectionDegree(uint256 newChallengeExecutionBisectionDegree)
                      external;
                  /**
                   * @notice Updates a whitelist address for its consumers
                   * @dev setting the newWhitelist to address(0) disables it for consumers
                   * @param whitelist old whitelist to be deprecated
                   * @param newWhitelist new whitelist to be used
                   * @param targets whitelist consumers to be triggered
                   */
                  function updateWhitelistConsumers(
                      address whitelist,
                      address newWhitelist,
                      address[] memory targets
                  ) external;
                  /**
                   * @notice Updates a whitelist's entries
                   * @dev user at position i will be assigned value i
                   * @param whitelist whitelist to be updated
                   * @param user users to be updated in the whitelist
                   * @param val if user is or not allowed in the whitelist
                   */
                  function setWhitelistEntries(
                      address whitelist,
                      address[] memory user,
                      bool[] memory val
                  ) external;
                  /**
                   * @notice Updates whether an address is a sequencer at the sequencer inbox
                   * @param newSequencer address to be modified
                   * @param isSequencer whether this address should be authorized as a sequencer
                   */
                  function setIsSequencer(address newSequencer, bool isSequencer) external;
                  /**
                   * @notice Upgrades the implementation of a beacon controlled by the rollup
                   * @param beacon address of beacon to be upgraded
                   * @param newImplementation new address of implementation
                   */
                  function upgradeBeacon(address beacon, address newImplementation) external;
                  function forceResolveChallenge(address[] memory stackerA, address[] memory stackerB) external;
                  function forceRefundStaker(address[] memory stacker) external;
                  function forceCreateNode(
                      bytes32 expectedNodeHash,
                      bytes32[3][2] calldata assertionBytes32Fields,
                      uint256[4][2] calldata assertionIntFields,
                      bytes calldata sequencerBatchProof,
                      uint256 beforeProposedBlock,
                      uint256 beforeInboxMaxCount,
                      uint256 prevNode
                  ) external;
                  function forceConfirmNode(
                      uint256 nodeNum,
                      bytes32 beforeSendAcc,
                      bytes calldata sendsData,
                      uint256[] calldata sendLengths,
                      uint256 afterSendCount,
                      bytes32 afterLogAcc,
                      uint256 afterLogCount
                  ) external;
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <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 GSN 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 payable) {
                      return msg.sender;
                  }
                  function _msgData() internal view virtual returns (bytes memory) {
                      this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
                      return msg.data;
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "./INode.sol";
              interface IRollupCore {
                  function _stakerMap(address stakerAddress)
                      external
                      view
                      returns (
                          uint256,
                          uint256,
                          uint256,
                          address,
                          bool
                      );
                  event RollupCreated(bytes32 machineHash);
                  event NodeCreated(
                      uint256 indexed nodeNum,
                      bytes32 indexed parentNodeHash,
                      bytes32 nodeHash,
                      bytes32 executionHash,
                      uint256 inboxMaxCount,
                      uint256 afterInboxBatchEndCount,
                      bytes32 afterInboxBatchAcc,
                      bytes32[3][2] assertionBytes32Fields,
                      uint256[4][2] assertionIntFields
                  );
                  event NodeConfirmed(
                      uint256 indexed nodeNum,
                      bytes32 afterSendAcc,
                      uint256 afterSendCount,
                      bytes32 afterLogAcc,
                      uint256 afterLogCount
                  );
                  event NodeRejected(uint256 indexed nodeNum);
                  event RollupChallengeStarted(
                      address indexed challengeContract,
                      address asserter,
                      address challenger,
                      uint256 challengedNode
                  );
                  event UserStakeUpdated(address indexed user, uint256 initialBalance, uint256 finalBalance);
                  event UserWithdrawableFundsUpdated(
                      address indexed user,
                      uint256 initialBalance,
                      uint256 finalBalance
                  );
                  function getNode(uint256 nodeNum) external view returns (INode);
                  /**
                   * @notice Get the address of the staker at the given index
                   * @param stakerNum Index of the staker
                   * @return Address of the staker
                   */
                  function getStakerAddress(uint256 stakerNum) external view returns (address);
                  /**
                   * @notice Check whether the given staker is staked
                   * @param staker Staker address to check
                   * @return True or False for whether the staker was staked
                   */
                  function isStaked(address staker) external view returns (bool);
                  /**
                   * @notice Get the latest staked node of the given staker
                   * @param staker Staker address to lookup
                   * @return Latest node staked of the staker
                   */
                  function latestStakedNode(address staker) external view returns (uint256);
                  /**
                   * @notice Get the current challenge of the given staker
                   * @param staker Staker address to lookup
                   * @return Current challenge of the staker
                   */
                  function currentChallenge(address staker) external view returns (address);
                  /**
                   * @notice Get the amount staked of the given staker
                   * @param staker Staker address to lookup
                   * @return Amount staked of the staker
                   */
                  function amountStaked(address staker) external view returns (uint256);
                  /**
                   * @notice Get the original staker address of the zombie at the given index
                   * @param zombieNum Index of the zombie to lookup
                   * @return Original staker address of the zombie
                   */
                  function zombieAddress(uint256 zombieNum) external view returns (address);
                  /**
                   * @notice Get Latest node that the given zombie at the given index is staked on
                   * @param zombieNum Index of the zombie to lookup
                   * @return Latest node that the given zombie is staked on
                   */
                  function zombieLatestStakedNode(uint256 zombieNum) external view returns (uint256);
                  /// @return Current number of un-removed zombies
                  function zombieCount() external view returns (uint256);
                  function isZombie(address staker) external view returns (bool);
                  /**
                   * @notice Get the amount of funds withdrawable by the given address
                   * @param owner Address to check the funds of
                   * @return Amount of funds withdrawable by owner
                   */
                  function withdrawableFunds(address owner) external view returns (uint256);
                  /**
                   * @return Index of the first unresolved node
                   * @dev If all nodes have been resolved, this will be latestNodeCreated + 1
                   */
                  function firstUnresolvedNode() external view returns (uint256);
                  /// @return Index of the latest confirmed node
                  function latestConfirmed() external view returns (uint256);
                  /// @return Index of the latest rollup node created
                  function latestNodeCreated() external view returns (uint256);
                  /// @return Ethereum block that the most recent stake was created
                  function lastStakeBlock() external view returns (uint256);
                  /// @return Number of active stakers currently staked
                  function stakerCount() external view returns (uint256);
                  /// @return Node hash as of this node number
                  function getNodeHash(uint256 index) external view returns (bytes32);
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              interface ISequencerInbox {
                  event SequencerBatchDelivered(
                      uint256 indexed firstMessageNum,
                      bytes32 indexed beforeAcc,
                      uint256 newMessageCount,
                      bytes32 afterAcc,
                      bytes transactions,
                      uint256[] lengths,
                      uint256[] sectionsMetadata,
                      uint256 seqBatchIndex,
                      address sequencer
                  );
                  event SequencerBatchDeliveredFromOrigin(
                      uint256 indexed firstMessageNum,
                      bytes32 indexed beforeAcc,
                      uint256 newMessageCount,
                      bytes32 afterAcc,
                      uint256 seqBatchIndex
                  );
                  event DelayedInboxForced(
                      uint256 indexed firstMessageNum,
                      bytes32 indexed beforeAcc,
                      uint256 newMessageCount,
                      uint256 totalDelayedMessagesRead,
                      bytes32[2] afterAccAndDelayed,
                      uint256 seqBatchIndex
                  );
                  /// @notice DEPRECATED - look at IsSequencerUpdated for new updates
                  // event SequencerAddressUpdated(address newAddress);
                  event IsSequencerUpdated(address addr, bool isSequencer);
                  event MaxDelayUpdated(uint256 newMaxDelayBlocks, uint256 newMaxDelaySeconds);
                  /// @notice DEPRECATED - look at MaxDelayUpdated for new updates
                  // event MaxDelayBlocksUpdated(uint256 newValue);
                  /// @notice DEPRECATED - look at MaxDelayUpdated for new updates
                  // event MaxDelaySecondsUpdated(uint256 newValue);
                  function setMaxDelay(uint256 newMaxDelayBlocks, uint256 newMaxDelaySeconds) external;
                  function setIsSequencer(address addr, bool isSequencer) external;
                  function messageCount() external view returns (uint256);
                  function maxDelayBlocks() external view returns (uint256);
                  function maxDelaySeconds() external view returns (uint256);
                  function inboxAccs(uint256 index) external view returns (bytes32);
                  function getInboxAccsLength() external view returns (uint256);
                  function proveInboxContainsMessage(bytes calldata proof, uint256 inboxCount)
                      external
                      view
                      returns (uint256, bytes32);
                  /// @notice DEPRECATED - use isSequencer instead
                  function sequencer() external view returns (address);
                  function isSequencer(address seq) external view returns (bool);
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              /**
               * @dev Wrappers over Solidity's arithmetic operations with added overflow
               * checks.
               *
               * Arithmetic operations in Solidity wrap on overflow. This can easily result
               * in bugs, because programmers usually assume that an overflow raises an
               * error, which is the standard behavior in high level programming languages.
               * `SafeMath` restores this intuition by reverting the transaction when an
               * operation overflows.
               *
               * Using this library instead of the unchecked operations eliminates an entire
               * class of bugs, so it's recommended to use it always.
               */
              library SafeMath {
                  /**
                   * @dev Returns the addition of two unsigned integers, with an overflow flag.
                   *
                   * _Available since v3.4._
                   */
                  function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      uint256 c = a + b;
                      if (c < a) return (false, 0);
                      return (true, c);
                  }
                  /**
                   * @dev Returns the substraction of two unsigned integers, with an overflow flag.
                   *
                   * _Available since v3.4._
                   */
                  function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      if (b > a) return (false, 0);
                      return (true, a - b);
                  }
                  /**
                   * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
                   *
                   * _Available since v3.4._
                   */
                  function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                      // benefit is lost if 'b' is also tested.
                      // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                      if (a == 0) return (true, 0);
                      uint256 c = a * b;
                      if (c / a != b) return (false, 0);
                      return (true, c);
                  }
                  /**
                   * @dev Returns the division of two unsigned integers, with a division by zero flag.
                   *
                   * _Available since v3.4._
                   */
                  function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      if (b == 0) return (false, 0);
                      return (true, a / b);
                  }
                  /**
                   * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
                   *
                   * _Available since v3.4._
                   */
                  function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                      if (b == 0) return (false, 0);
                      return (true, a % b);
                  }
                  /**
                   * @dev Returns the addition of two unsigned integers, reverting on
                   * overflow.
                   *
                   * Counterpart to Solidity's `+` operator.
                   *
                   * Requirements:
                   *
                   * - Addition cannot overflow.
                   */
                  function add(uint256 a, uint256 b) internal pure returns (uint256) {
                      uint256 c = a + b;
                      require(c >= a, "SafeMath: addition overflow");
                      return c;
                  }
                  /**
                   * @dev Returns the subtraction of two unsigned integers, reverting on
                   * overflow (when the result is negative).
                   *
                   * Counterpart to Solidity's `-` operator.
                   *
                   * Requirements:
                   *
                   * - Subtraction cannot overflow.
                   */
                  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                      require(b <= a, "SafeMath: subtraction overflow");
                      return a - b;
                  }
                  /**
                   * @dev Returns the multiplication of two unsigned integers, reverting on
                   * overflow.
                   *
                   * Counterpart to Solidity's `*` operator.
                   *
                   * Requirements:
                   *
                   * - Multiplication cannot overflow.
                   */
                  function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                      if (a == 0) return 0;
                      uint256 c = a * b;
                      require(c / a == b, "SafeMath: multiplication overflow");
                      return c;
                  }
                  /**
                   * @dev Returns the integer division of two unsigned integers, reverting on
                   * division by zero. The result is rounded towards zero.
                   *
                   * Counterpart to Solidity's `/` operator. Note: this function uses a
                   * `revert` opcode (which leaves remaining gas untouched) while Solidity
                   * uses an invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function div(uint256 a, uint256 b) internal pure returns (uint256) {
                      require(b > 0, "SafeMath: division by zero");
                      return a / b;
                  }
                  /**
                   * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                   * reverting when dividing by zero.
                   *
                   * Counterpart to Solidity's `%` operator. This function uses a `revert`
                   * opcode (which leaves remaining gas untouched) while Solidity uses an
                   * invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function mod(uint256 a, uint256 b) internal pure returns (uint256) {
                      require(b > 0, "SafeMath: modulo by zero");
                      return a % b;
                  }
                  /**
                   * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
                   * overflow (when the result is negative).
                   *
                   * CAUTION: This function is deprecated because it requires allocating memory for the error
                   * message unnecessarily. For custom revert reasons use {trySub}.
                   *
                   * Counterpart to Solidity's `-` operator.
                   *
                   * Requirements:
                   *
                   * - Subtraction cannot overflow.
                   */
                  function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                      require(b <= a, errorMessage);
                      return a - b;
                  }
                  /**
                   * @dev Returns the integer division of two unsigned integers, reverting with custom message on
                   * division by zero. The result is rounded towards zero.
                   *
                   * CAUTION: This function is deprecated because it requires allocating memory for the error
                   * message unnecessarily. For custom revert reasons use {tryDiv}.
                   *
                   * Counterpart to Solidity's `/` operator. Note: this function uses a
                   * `revert` opcode (which leaves remaining gas untouched) while Solidity
                   * uses an invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                      require(b > 0, errorMessage);
                      return a / b;
                  }
                  /**
                   * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                   * reverting with custom message when dividing by zero.
                   *
                   * CAUTION: This function is deprecated because it requires allocating memory for the error
                   * message unnecessarily. For custom revert reasons use {tryMod}.
                   *
                   * Counterpart to Solidity's `%` operator. This function uses a `revert`
                   * opcode (which leaves remaining gas untouched) while Solidity uses an
                   * invalid opcode to revert (consuming all remaining gas).
                   *
                   * Requirements:
                   *
                   * - The divisor cannot be zero.
                   */
                  function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                      require(b > 0, errorMessage);
                      return a % b;
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2019-2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "../libraries/MerkleLib.sol";
              import "@openzeppelin/contracts/math/SafeMath.sol";
              library ChallengeLib {
                  using SafeMath for uint256;
                  function firstSegmentSize(uint256 totalCount, uint256 bisectionCount)
                      internal
                      pure
                      returns (uint256)
                  {
                      return totalCount / bisectionCount + (totalCount % bisectionCount);
                  }
                  function otherSegmentSize(uint256 totalCount, uint256 bisectionCount)
                      internal
                      pure
                      returns (uint256)
                  {
                      return totalCount / bisectionCount;
                  }
                  function bisectionChunkHash(
                      uint256 _segmentStart,
                      uint256 _segmentLength,
                      bytes32 _startHash,
                      bytes32 _endHash
                  ) internal pure returns (bytes32) {
                      return keccak256(abi.encodePacked(_segmentStart, _segmentLength, _startHash, _endHash));
                  }
                  function assertionHash(uint256 _avmGasUsed, bytes32 _restHash) internal pure returns (bytes32) {
                      // Note: make sure this doesn't return Challenge.UNREACHABLE_ASSERTION (currently 0)
                      return keccak256(abi.encodePacked(_avmGasUsed, _restHash));
                  }
                  function assertionRestHash(
                      uint256 _totalMessagesRead,
                      bytes32 _machineState,
                      bytes32 _sendAcc,
                      uint256 _sendCount,
                      bytes32 _logAcc,
                      uint256 _logCount
                  ) internal pure returns (bytes32) {
                      return
                          keccak256(
                              abi.encodePacked(
                                  _totalMessagesRead,
                                  _machineState,
                                  _sendAcc,
                                  _sendCount,
                                  _logAcc,
                                  _logCount
                              )
                          );
                  }
                  function updatedBisectionRoot(
                      bytes32[] memory _chainHashes,
                      uint256 _challengedSegmentStart,
                      uint256 _challengedSegmentLength
                  ) internal pure returns (bytes32) {
                      uint256 bisectionCount = _chainHashes.length - 1;
                      bytes32[] memory hashes = new bytes32[](bisectionCount);
                      uint256 chunkSize = ChallengeLib.firstSegmentSize(_challengedSegmentLength, bisectionCount);
                      uint256 segmentStart = _challengedSegmentStart;
                      hashes[0] = ChallengeLib.bisectionChunkHash(
                          segmentStart,
                          chunkSize,
                          _chainHashes[0],
                          _chainHashes[1]
                      );
                      segmentStart = segmentStart.add(chunkSize);
                      chunkSize = ChallengeLib.otherSegmentSize(_challengedSegmentLength, bisectionCount);
                      for (uint256 i = 1; i < bisectionCount; i++) {
                          hashes[i] = ChallengeLib.bisectionChunkHash(
                              segmentStart,
                              chunkSize,
                              _chainHashes[i],
                              _chainHashes[i + 1]
                          );
                          segmentStart = segmentStart.add(chunkSize);
                      }
                      return MerkleLib.generateRoot(hashes);
                  }
                  function verifySegmentProof(
                      bytes32 challengeState,
                      bytes32 item,
                      bytes32[] calldata _merkleNodes,
                      uint256 _merkleRoute
                  ) internal pure returns (bool) {
                      return challengeState == MerkleLib.calculateRoot(_merkleNodes, _merkleRoute, item);
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2019-2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              library MerkleLib {
                  function generateRoot(bytes32[] memory _hashes) internal pure returns (bytes32) {
                      bytes32[] memory prevLayer = _hashes;
                      while (prevLayer.length > 1) {
                          bytes32[] memory nextLayer = new bytes32[]((prevLayer.length + 1) / 2);
                          for (uint256 i = 0; i < nextLayer.length; i++) {
                              if (2 * i + 1 < prevLayer.length) {
                                  nextLayer[i] = keccak256(
                                      abi.encodePacked(prevLayer[2 * i], prevLayer[2 * i + 1])
                                  );
                              } else {
                                  nextLayer[i] = prevLayer[2 * i];
                              }
                          }
                          prevLayer = nextLayer;
                      }
                      return prevLayer[0];
                  }
                  function calculateRoot(
                      bytes32[] memory nodes,
                      uint256 route,
                      bytes32 item
                  ) internal pure returns (bytes32) {
                      uint256 proofItems = nodes.length;
                      require(proofItems <= 256);
                      bytes32 h = item;
                      for (uint256 i = 0; i < proofItems; i++) {
                          if (route % 2 == 0) {
                              h = keccak256(abi.encodePacked(nodes[i], h));
                          } else {
                              h = keccak256(abi.encodePacked(h, nodes[i]));
                          }
                          route /= 2;
                      }
                      return h;
                  }
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2019, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              interface ICloneable {
                  function isMaster() external view returns (bool);
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2020, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "../bridge/interfaces/IBridge.sol";
              import "../bridge/interfaces/ISequencerInbox.sol";
              interface IOneStepProof {
                  // Bridges is sequencer bridge then delayed bridge
                  function executeStep(
                      address[2] calldata bridges,
                      uint256 initialMessagesRead,
                      bytes32[2] calldata accs,
                      bytes calldata proof,
                      bytes calldata bproof
                  )
                      external
                      view
                      returns (
                          uint64 gas,
                          uint256 afterMessagesRead,
                          bytes32[4] memory fields
                      );
                  function executeStepDebug(
                      address[2] calldata bridges,
                      uint256 initialMessagesRead,
                      bytes32[2] calldata accs,
                      bytes calldata proof,
                      bytes calldata bproof
                  ) external view returns (string memory startMachine, string memory afterMachine);
              }
              // SPDX-License-Identifier: Apache-2.0
              /*
               * Copyright 2019-2021, Offchain Labs, Inc.
               *
               * Licensed under the Apache License, Version 2.0 (the "License");
               * you may not use this file except in compliance with the License.
               * You may obtain a copy of the License at
               *
               *    http://www.apache.org/licenses/LICENSE-2.0
               *
               * Unless required by applicable law or agreed to in writing, software
               * distributed under the License is distributed on an "AS IS" BASIS,
               * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
               * See the License for the specific language governing permissions and
               * limitations under the License.
               */
              pragma solidity ^0.6.11;
              import "./interfaces/IOutbox.sol";
              import "./interfaces/IBridge.sol";
              import "./Messages.sol";
              import "../libraries/MerkleLib.sol";
              import "../libraries/BytesLib.sol";
              import "../libraries/Cloneable.sol";
              import "@openzeppelin/contracts/proxy/BeaconProxy.sol";
              import "@openzeppelin/contracts/proxy/UpgradeableBeacon.sol";
              contract Outbox is IOutbox, Cloneable {
                  using BytesLib for bytes;
                  struct OutboxEntry {
                      // merkle root of outputs
                      bytes32 root;
                      // mapping from output id => is spent
                      mapping(bytes32 => bool) spentOutput;
                  }
                  bytes1 internal constant MSG_ROOT = 0;
                  uint8 internal constant SendType_sendTxToL1 = 3;
                  address public rollup;
                  IBridge public bridge;
                  mapping(uint256 => OutboxEntry) public outboxEntries;
                  struct L2ToL1Context {
                      uint128 l2Block;
                      uint128 l1Block;
                      uint128 timestamp;
                      uint128 batchNum;
                      bytes32 outputId;
                      address sender;
                  }
                  // Note, these variables are set and then wiped during a single transaction.
                  // Therefore their values don't need to be maintained, and their slots will
                  // be empty outside of transactions
                  L2ToL1Context internal context;
                  uint128 public constant OUTBOX_VERSION = 1;
                  function initialize(address _rollup, IBridge _bridge) external {
                      require(rollup == address(0), "ALREADY_INIT");
                      rollup = _rollup;
                      bridge = _bridge;
                  }
                  /// @notice When l2ToL1Sender returns a nonzero address, the message was originated by an L2 account
                  /// When the return value is zero, that means this is a system message
                  /// @dev the l2ToL1Sender behaves as the tx.origin, the msg.sender should be validated to protect against reentrancies
                  function l2ToL1Sender() external view override returns (address) {
                      return context.sender;
                  }
                  function l2ToL1Block() external view override returns (uint256) {
                      return uint256(context.l2Block);
                  }
                  function l2ToL1EthBlock() external view override returns (uint256) {
                      return uint256(context.l1Block);
                  }
                  function l2ToL1Timestamp() external view override returns (uint256) {
                      return uint256(context.timestamp);
                  }
                  function l2ToL1BatchNum() external view override returns (uint256) {
                      return uint256(context.batchNum);
                  }
                  function l2ToL1OutputId() external view override returns (bytes32) {
                      return context.outputId;
                  }
                  function processOutgoingMessages(bytes calldata sendsData, uint256[] calldata sendLengths)
                      external
                      override
                  {
                      require(msg.sender == rollup, "ONLY_ROLLUP");
                      // If we've reached here, we've already confirmed that sum(sendLengths) == sendsData.length
                      uint256 messageCount = sendLengths.length;
                      uint256 offset = 0;
                      for (uint256 i = 0; i < messageCount; i++) {
                          handleOutgoingMessage(bytes(sendsData[offset:offset + sendLengths[i]]));
                          offset += sendLengths[i];
                      }
                  }
                  function handleOutgoingMessage(bytes memory data) private {
                      // Otherwise we have an unsupported message type and we skip the message
                      if (data[0] == MSG_ROOT) {
                          require(data.length == 97, "BAD_LENGTH");
                          uint256 batchNum = data.toUint(1);
                          // Ensure no outbox entry already exists w/ batch number
                          require(!outboxEntryExists(batchNum), "ENTRY_ALREADY_EXISTS");
                          // This is the total number of msgs included in the root, it can be used to
                          // detect when all msgs were executed against a root.
                          // It currently isn't stored, but instead emitted in an event for utility
                          uint256 numInBatch = data.toUint(33);
                          bytes32 outputRoot = data.toBytes32(65);
                          OutboxEntry memory newOutboxEntry = OutboxEntry(outputRoot);
                          outboxEntries[batchNum] = newOutboxEntry;
                          // keeping redundant batchnum in event (batchnum and old outboxindex field) for outbox version interface compatibility
                          emit OutboxEntryCreated(batchNum, batchNum, outputRoot, numInBatch);
                      }
                  }
                  /**
                   * @notice Executes a messages in an Outbox entry.
                   * @dev Reverts if dispute period hasn't expired, since the outbox entry
                   * is only created once the rollup confirms the respective assertion.
                   * @param batchNum Index of OutboxEntry in outboxEntries array
                   * @param proof Merkle proof of message inclusion in outbox entry
                   * @param index Merkle path to message
                   * @param l2Sender sender if original message (i.e., caller of ArbSys.sendTxToL1)
                   * @param destAddr destination address for L1 contract call
                   * @param l2Block l2 block number at which sendTxToL1 call was made
                   * @param l1Block l1 block number at which sendTxToL1 call was made
                   * @param l2Timestamp l2 Timestamp at which sendTxToL1 call was made
                   * @param amount value in L1 message in wei
                   * @param calldataForL1 abi-encoded L1 message data
                   */
                  function executeTransaction(
                      uint256 batchNum,
                      bytes32[] calldata proof,
                      uint256 index,
                      address l2Sender,
                      address destAddr,
                      uint256 l2Block,
                      uint256 l1Block,
                      uint256 l2Timestamp,
                      uint256 amount,
                      bytes calldata calldataForL1
                  ) external virtual {
                      bytes32 outputId;
                      {
                          bytes32 userTx = calculateItemHash(
                              l2Sender,
                              destAddr,
                              l2Block,
                              l1Block,
                              l2Timestamp,
                              amount,
                              calldataForL1
                          );
                          outputId = recordOutputAsSpent(batchNum, proof, index, userTx);
                          emit OutBoxTransactionExecuted(destAddr, l2Sender, batchNum, index);
                      }
                      // we temporarily store the previous values so the outbox can naturally
                      // unwind itself when there are nested calls to `executeTransaction`
                      L2ToL1Context memory prevContext = context;
                      context = L2ToL1Context({
                          sender: l2Sender,
                          l2Block: uint128(l2Block),
                          l1Block: uint128(l1Block),
                          timestamp: uint128(l2Timestamp),
                          batchNum: uint128(batchNum),
                          outputId: outputId
                      });
                      // set and reset vars around execution so they remain valid during call
                      executeBridgeCall(destAddr, amount, calldataForL1);
                      context = prevContext;
                  }
                  function recordOutputAsSpent(
                      uint256 batchNum,
                      bytes32[] memory proof,
                      uint256 path,
                      bytes32 item
                  ) internal returns (bytes32) {
                      require(proof.length < 256, "PROOF_TOO_LONG");
                      require(path < 2**proof.length, "PATH_NOT_MINIMAL");
                      // Hash the leaf an extra time to prove it's a leaf
                      bytes32 calcRoot = calculateMerkleRoot(proof, path, item);
                      OutboxEntry storage outboxEntry = outboxEntries[batchNum];
                      require(outboxEntry.root != bytes32(0), "NO_OUTBOX_ENTRY");
                      // With a minimal path, the pair of path and proof length should always identify
                      // a unique leaf. The path itself is not enough since the path length to different
                      // leaves could potentially be different
                      bytes32 uniqueKey = keccak256(abi.encodePacked(path, proof.length));
                      require(!outboxEntry.spentOutput[uniqueKey], "ALREADY_SPENT");
                      require(calcRoot == outboxEntry.root, "BAD_ROOT");
                      outboxEntry.spentOutput[uniqueKey] = true;
                      return uniqueKey;
                  }
                  function executeBridgeCall(
                      address destAddr,
                      uint256 amount,
                      bytes memory data
                  ) internal {
                      (bool success, bytes memory returndata) = bridge.executeCall(destAddr, amount, data);
                      if (!success) {
                          if (returndata.length > 0) {
                              // solhint-disable-next-line no-inline-assembly
                              assembly {
                                  let returndata_size := mload(returndata)
                                  revert(add(32, returndata), returndata_size)
                              }
                          } else {
                              revert("BRIDGE_CALL_FAILED");
                          }
                      }
                  }
                  function calculateItemHash(
                      address l2Sender,
                      address destAddr,
                      uint256 l2Block,
                      uint256 l1Block,
                      uint256 l2Timestamp,
                      uint256 amount,
                      bytes calldata calldataForL1
                  ) public pure returns (bytes32) {
                      return
                          keccak256(
                              abi.encodePacked(
                                  SendType_sendTxToL1,
                                  uint256(uint160(bytes20(l2Sender))),
                                  uint256(uint160(bytes20(destAddr))),
                                  l2Block,
                                  l1Block,
                                  l2Timestamp,
                                  amount,
                                  calldataForL1
                              )
                          );
                  }
                  function calculateMerkleRoot(
                      bytes32[] memory proof,
                      uint256 path,
                      bytes32 item
                  ) public pure returns (bytes32) {
                      return MerkleLib.calculateRoot(proof, path, keccak256(abi.encodePacked(item)));
                  }
                  function outboxEntryExists(uint256 batchNum) public view override returns (bool) {
                      return outboxEntries[batchNum].root != bytes32(0);
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              import "../utils/ContextUpgradeable.sol";
              import "../proxy/Initializable.sol";
              /**
               * @dev Contract module which provides a basic access control mechanism, where
               * there is an account (an owner) that can be granted exclusive access to
               * specific functions.
               *
               * By default, the owner account will be the one that deploys the contract. This
               * can later be changed with {transferOwnership}.
               *
               * This module is used through inheritance. It will make available the modifier
               * `onlyOwner`, which can be applied to your functions to restrict their use to
               * the owner.
               */
              abstract contract OwnableUpgradeable is Initializable, ContextUpgradeable {
                  address private _owner;
                  event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                  /**
                   * @dev Initializes the contract setting the deployer as the initial owner.
                   */
                  function __Ownable_init() internal initializer {
                      __Context_init_unchained();
                      __Ownable_init_unchained();
                  }
                  function __Ownable_init_unchained() internal initializer {
                      address msgSender = _msgSender();
                      _owner = msgSender;
                      emit OwnershipTransferred(address(0), msgSender);
                  }
                  /**
                   * @dev Returns the address of the current owner.
                   */
                  function owner() public view virtual returns (address) {
                      return _owner;
                  }
                  /**
                   * @dev Throws if called by any account other than the owner.
                   */
                  modifier onlyOwner() {
                      require(owner() == _msgSender(), "Ownable: caller is not the owner");
                      _;
                  }
                  /**
                   * @dev Leaves the contract without owner. It will not be possible to call
                   * `onlyOwner` functions anymore. Can only be called by the current owner.
                   *
                   * NOTE: Renouncing ownership will leave the contract without an owner,
                   * thereby removing any functionality that is only available to the owner.
                   */
                  function renounceOwnership() public virtual onlyOwner {
                      emit OwnershipTransferred(_owner, address(0));
                      _owner = address(0);
                  }
                  /**
                   * @dev Transfers ownership of the contract to a new account (`newOwner`).
                   * Can only be called by the current owner.
                   */
                  function transferOwnership(address newOwner) public virtual onlyOwner {
                      require(newOwner != address(0), "Ownable: new owner is the zero address");
                      emit OwnershipTransferred(_owner, newOwner);
                      _owner = newOwner;
                  }
                  uint256[49] private __gap;
              }
              // SPDX-License-Identifier: MIT
              /*
               * @title Solidity Bytes Arrays Utils
               * @author Gonçalo Sá <[email protected]>
               *
               * @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 ^0.6.11;
              /* solhint-disable no-inline-assembly */
              library BytesLib {
                  function toAddress(bytes memory _bytes, uint256 _start) internal pure returns (address) {
                      require(_bytes.length >= (_start + 20), "Read out of bounds");
                      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), "Read out of bounds");
                      uint8 tempUint;
                      assembly {
                          tempUint := mload(add(add(_bytes, 0x1), _start))
                      }
                      return tempUint;
                  }
                  function toUint(bytes memory _bytes, uint256 _start) internal pure returns (uint256) {
                      require(_bytes.length >= (_start + 32), "Read out of bounds");
                      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), "Read out of bounds");
                      bytes32 tempBytes32;
                      assembly {
                          tempBytes32 := mload(add(add(_bytes, 0x20), _start))
                      }
                      return tempBytes32;
                  }
              }
              /* solhint-enable no-inline-assembly */
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              import "./Proxy.sol";
              import "../utils/Address.sol";
              import "./IBeacon.sol";
              /**
               * @dev This contract implements a proxy that gets the implementation address for each call from a {UpgradeableBeacon}.
               *
               * The beacon address is stored in storage slot `uint256(keccak256('eip1967.proxy.beacon')) - 1`, so that it doesn't
               * conflict with the storage layout of the implementation behind the proxy.
               *
               * _Available since v3.4._
               */
              contract BeaconProxy is Proxy {
                  /**
                   * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
                   * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
                   */
                  bytes32 private constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
                  /**
                   * @dev Initializes the proxy with `beacon`.
                   *
                   * If `data` is nonempty, it's used as data in a delegate call to the implementation returned by the beacon. This
                   * will typically be an encoded function call, and allows initializating the storage of the proxy like a Solidity
                   * constructor.
                   *
                   * Requirements:
                   *
                   * - `beacon` must be a contract with the interface {IBeacon}.
                   */
                  constructor(address beacon, bytes memory data) public payable {
                      assert(_BEACON_SLOT == bytes32(uint256(keccak256("eip1967.proxy.beacon")) - 1));
                      _setBeacon(beacon, data);
                  }
                  /**
                   * @dev Returns the current beacon address.
                   */
                  function _beacon() internal view virtual returns (address beacon) {
                      bytes32 slot = _BEACON_SLOT;
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          beacon := sload(slot)
                      }
                  }
                  /**
                   * @dev Returns the current implementation address of the associated beacon.
                   */
                  function _implementation() internal view virtual override returns (address) {
                      return IBeacon(_beacon()).implementation();
                  }
                  /**
                   * @dev Changes the proxy to use a new beacon.
                   *
                   * If `data` is nonempty, it's used as data in a delegate call to the implementation returned by the beacon.
                   *
                   * Requirements:
                   *
                   * - `beacon` must be a contract.
                   * - The implementation returned by `beacon` must be a contract.
                   */
                  function _setBeacon(address beacon, bytes memory data) internal virtual {
                      require(
                          Address.isContract(beacon),
                          "BeaconProxy: beacon is not a contract"
                      );
                      require(
                          Address.isContract(IBeacon(beacon).implementation()),
                          "BeaconProxy: beacon implementation is not a contract"
                      );
                      bytes32 slot = _BEACON_SLOT;
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          sstore(slot, beacon)
                      }
                      if (data.length > 0) {
                          Address.functionDelegateCall(_implementation(), data, "BeaconProxy: function call failed");
                      }
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              import "./IBeacon.sol";
              import "../access/Ownable.sol";
              import "../utils/Address.sol";
              /**
               * @dev This contract is used in conjunction with one or more instances of {BeaconProxy} to determine their
               * implementation contract, which is where they will delegate all function calls.
               *
               * An owner is able to change the implementation the beacon points to, thus upgrading the proxies that use this beacon.
               */
              contract UpgradeableBeacon is IBeacon, Ownable {
                  address private _implementation;
                  /**
                   * @dev Emitted when the implementation returned by the beacon is changed.
                   */
                  event Upgraded(address indexed implementation);
                  /**
                   * @dev Sets the address of the initial implementation, and the deployer account as the owner who can upgrade the
                   * beacon.
                   */
                  constructor(address implementation_) public {
                      _setImplementation(implementation_);
                  }
                  /**
                   * @dev Returns the current implementation address.
                   */
                  function implementation() public view virtual override returns (address) {
                      return _implementation;
                  }
                  /**
                   * @dev Upgrades the beacon to a new implementation.
                   *
                   * Emits an {Upgraded} event.
                   *
                   * Requirements:
                   *
                   * - msg.sender must be the owner of the contract.
                   * - `newImplementation` must be a contract.
                   */
                  function upgradeTo(address newImplementation) public virtual onlyOwner {
                      _setImplementation(newImplementation);
                      emit Upgraded(newImplementation);
                  }
                  /**
                   * @dev Sets the implementation contract address for this beacon
                   *
                   * Requirements:
                   *
                   * - `newImplementation` must be a contract.
                   */
                  function _setImplementation(address newImplementation) private {
                      require(Address.isContract(newImplementation), "UpgradeableBeacon: implementation is not a contract");
                      _implementation = newImplementation;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              /**
               * @dev This is the interface that {BeaconProxy} expects of its beacon.
               */
              interface IBeacon {
                  /**
                   * @dev Must return an address that can be used as a delegate call target.
                   *
                   * {BeaconProxy} will check that this address is a contract.
                   */
                  function implementation() external view returns (address);
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              import "../utils/Context.sol";
              /**
               * @dev Contract module which provides a basic access control mechanism, where
               * there is an account (an owner) that can be granted exclusive access to
               * specific functions.
               *
               * By default, the owner account will be the one that deploys the contract. This
               * can later be changed with {transferOwnership}.
               *
               * This module is used through inheritance. It will make available the modifier
               * `onlyOwner`, which can be applied to your functions to restrict their use to
               * the owner.
               */
              abstract contract Ownable is Context {
                  address private _owner;
                  event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                  /**
                   * @dev Initializes the contract setting the deployer as the initial owner.
                   */
                  constructor () internal {
                      address msgSender = _msgSender();
                      _owner = msgSender;
                      emit OwnershipTransferred(address(0), msgSender);
                  }
                  /**
                   * @dev Returns the address of the current owner.
                   */
                  function owner() public view virtual returns (address) {
                      return _owner;
                  }
                  /**
                   * @dev Throws if called by any account other than the owner.
                   */
                  modifier onlyOwner() {
                      require(owner() == _msgSender(), "Ownable: caller is not the owner");
                      _;
                  }
                  /**
                   * @dev Leaves the contract without owner. It will not be possible to call
                   * `onlyOwner` functions anymore. Can only be called by the current owner.
                   *
                   * NOTE: Renouncing ownership will leave the contract without an owner,
                   * thereby removing any functionality that is only available to the owner.
                   */
                  function renounceOwnership() public virtual onlyOwner {
                      emit OwnershipTransferred(_owner, address(0));
                      _owner = address(0);
                  }
                  /**
                   * @dev Transfers ownership of the contract to a new account (`newOwner`).
                   * Can only be called by the current owner.
                   */
                  function transferOwnership(address newOwner) public virtual onlyOwner {
                      require(newOwner != address(0), "Ownable: new owner is the zero address");
                      emit OwnershipTransferred(_owner, newOwner);
                      _owner = newOwner;
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.0 <0.8.0;
              import "../proxy/Initializable.sol";
              /*
               * @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 GSN 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 ContextUpgradeable is Initializable {
                  function __Context_init() internal initializer {
                      __Context_init_unchained();
                  }
                  function __Context_init_unchained() internal initializer {
                  }
                  function _msgSender() internal view virtual returns (address payable) {
                      return msg.sender;
                  }
                  function _msgData() internal view virtual returns (bytes memory) {
                      this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
                      return msg.data;
                  }
                  uint256[50] private __gap;
              }
              // SPDX-License-Identifier: MIT
              // solhint-disable-next-line compiler-version
              pragma solidity >=0.4.24 <0.8.0;
              import "../utils/AddressUpgradeable.sol";
              /**
               * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
               * behind a proxy. Since a proxied contract can't have a constructor, it's common to move constructor logic to an
               * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
               * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
               *
               * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
               * possible by providing the encoded function call as the `_data` argument to {UpgradeableProxy-constructor}.
               *
               * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
               * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
               */
              abstract contract Initializable {
                  /**
                   * @dev Indicates that the contract has been initialized.
                   */
                  bool private _initialized;
                  /**
                   * @dev Indicates that the contract is in the process of being initialized.
                   */
                  bool private _initializing;
                  /**
                   * @dev Modifier to protect an initializer function from being invoked twice.
                   */
                  modifier initializer() {
                      require(_initializing || _isConstructor() || !_initialized, "Initializable: contract is already initialized");
                      bool isTopLevelCall = !_initializing;
                      if (isTopLevelCall) {
                          _initializing = true;
                          _initialized = true;
                      }
                      _;
                      if (isTopLevelCall) {
                          _initializing = false;
                      }
                  }
                  /// @dev Returns true if and only if the function is running in the constructor
                  function _isConstructor() private view returns (bool) {
                      return !AddressUpgradeable.isContract(address(this));
                  }
              }
              // SPDX-License-Identifier: MIT
              pragma solidity >=0.6.2 <0.8.0;
              /**
               * @dev Collection of functions related to the address type
               */
              library AddressUpgradeable {
                  /**
                   * @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
                   * ====
                   */
                  function isContract(address account) internal view returns (bool) {
                      // This method relies on extcodesize, which returns 0 for contracts in
                      // construction, since the code is only stored at the end of the
                      // constructor execution.
                      uint256 size;
                      // solhint-disable-next-line no-inline-assembly
                      assembly { size := extcodesize(account) }
                      return size > 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");
                      // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (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");
                      // solhint-disable-next-line avoid-low-level-calls
                      (bool success, bytes memory returndata) = target.staticcall(data);
                      return _verifyCallResult(success, returndata, errorMessage);
                  }
                  function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private 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
                              // solhint-disable-next-line no-inline-assembly
                              assembly {
                                  let returndata_size := mload(returndata)
                                  revert(add(32, returndata), returndata_size)
                              }
                          } else {
                              revert(errorMessage);
                          }
                      }
                  }
              }