Contract Address Details

// SPDX-License-Identifier: GPL-3.0-only
// Sources flattened with hardhat v2.12.2 https://hardhat.org

// File contracts/utils/Ownable.sol

pragma solidity 0.8.19;

/**
 * @title Ownable
 * @dev The Ownable contract provides a simple way to manage ownership of a contract
 * and allows for ownership to be transferred to a nominated address.
 */
abstract contract Ownable {
    address private _owner;
    address private _nominee;

    event OwnerNominated(address indexed nominee);
    event OwnerClaimed(address indexed claimer);

    error OnlyOwner();
    error OnlyNominee();

    /**
     * @dev Sets the contract's owner to the address that is passed to the constructor.
     */
    constructor(address owner_) {
        _claimOwner(owner_);
    }

    /**
     * @dev Modifier that restricts access to only the contract's owner.
     * Throws an error if the caller is not the owner.
     */
    modifier onlyOwner() {
        if (msg.sender != _owner) revert OnlyOwner();
        _;
    }

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

    /**
     * @dev Returns the current nominee for ownership of the contract.
     */
    function nominee() external view returns (address) {
        return _nominee;
    }

    /**
     * @dev Allows the current owner to nominate a new owner for the contract.
     * Throws an error if the caller is not the owner.
     * Emits an `OwnerNominated` event with the address of the nominee.
     */
    function nominateOwner(address nominee_) external {
        if (msg.sender != _owner) revert OnlyOwner();
        _nominee = nominee_;
        emit OwnerNominated(_nominee);
    }

    /**
     * @dev Allows the nominated owner to claim ownership of the contract.
     * Throws an error if the caller is not the nominee.
     * Sets the nominated owner as the new owner of the contract.
     * Emits an `OwnerClaimed` event with the address of the new owner.
     */
    function claimOwner() external {
        if (msg.sender != _nominee) revert OnlyNominee();
        _claimOwner(msg.sender);
    }

    /**
     * @dev Internal function that sets the owner of the contract to the specified address
     * and sets the nominee to address(0).
     */
    function _claimOwner(address claimer_) internal {
        _owner = claimer_;
        _nominee = address(0);
        emit OwnerClaimed(claimer_);
    }
}


// File contracts/utils/AccessControl.sol

pragma solidity 0.8.19;

/**
 * @title AccessControl
 * @dev This abstract contract implements access control mechanism based on roles.
 * Each role can have one or more addresses associated with it, which are granted
 * permission to execute functions with the onlyRole modifier.
 */
abstract contract AccessControl is Ownable {
    /**
     * @dev A mapping of roles to a mapping of addresses to boolean values indicating whether or not they have the role.
     */
    mapping(bytes32 => mapping(address => bool)) private _permits;

    /**
     * @dev Emitted when a role is granted to an address.
     */
    event RoleGranted(bytes32 indexed role, address indexed grantee);

    /**
     * @dev Emitted when a role is revoked from an address.
     */
    event RoleRevoked(bytes32 indexed role, address indexed revokee);

    /**
     * @dev Error message thrown when an address does not have permission to execute a function with onlyRole modifier.
     */
    error NoPermit(bytes32 role);

    /**
     * @dev Constructor that sets the owner of the contract.
     */
    constructor(address owner_) Ownable(owner_) {}

    /**
     * @dev Modifier that restricts access to addresses having roles
     * Throws an error if the caller do not have permit
     */
    modifier onlyRole(bytes32 role) {
        if (!_permits[role][msg.sender]) revert NoPermit(role);
        _;
    }

    /**
     * @dev Checks and reverts if an address do not have a specific role.
     * @param role_ The role to check.
     * @param address_ The address to check.
     */
    function _checkRole(bytes32 role_, address address_) internal virtual {
        if (!_hasRole(role_, address_)) revert NoPermit(role_);
    }

    /**
     * @dev Grants a role to a given address.
     * @param role_ The role to grant.
     * @param grantee_ The address to grant the role to.
     * Emits a RoleGranted event.
     * Can only be called by the owner of the contract.
     */
    function grantRole(
        bytes32 role_,
        address grantee_
    ) external virtual onlyOwner {
        _grantRole(role_, grantee_);
    }

    /**
     * @dev Revokes a role from a given address.
     * @param role_ The role to revoke.
     * @param revokee_ The address to revoke the role from.
     * Emits a RoleRevoked event.
     * Can only be called by the owner of the contract.
     */
    function revokeRole(
        bytes32 role_,
        address revokee_
    ) external virtual onlyOwner {
        _revokeRole(role_, revokee_);
    }

    /**
     * @dev Internal function to grant a role to a given address.
     * @param role_ The role to grant.
     * @param grantee_ The address to grant the role to.
     * Emits a RoleGranted event.
     */
    function _grantRole(bytes32 role_, address grantee_) internal {
        _permits[role_][grantee_] = true;
        emit RoleGranted(role_, grantee_);
    }

    /**
     * @dev Internal function to revoke a role from a given address.
     * @param role_ The role to revoke.
     * @param revokee_ The address to revoke the role from.
     * Emits a RoleRevoked event.
     */
    function _revokeRole(bytes32 role_, address revokee_) internal {
        _permits[role_][revokee_] = false;
        emit RoleRevoked(role_, revokee_);
    }

    /**
     * @dev Checks whether an address has a specific role.
     * @param role_ The role to check.
     * @param address_ The address to check.
     * @return A boolean value indicating whether or not the address has the role.
     */
    function hasRole(
        bytes32 role_,
        address address_
    ) external view returns (bool) {
        return _hasRole(role_, address_);
    }

    function _hasRole(
        bytes32 role_,
        address address_
    ) internal view returns (bool) {
        return _permits[role_][address_];
    }
}


// File contracts/interfaces/IDecapacitor.sol

pragma solidity 0.8.19;

/**
 * @title IDecapacitor interface
 * @notice Interface for a contract that verifies if a packed message is part of a packet or not
 */
interface IDecapacitor {
    /**
     * @notice Returns true if packed message is part of root.
     * @param root_ root hash of the packet.
     * @param packedMessage_ packed message which needs to be verified.
     * @param proof_ proof used to determine the inclusion
     * @dev This function is kept as view instead of pure, as in future we may have stateful decapacitors
     * @return isIncluded boolean indicating whether the message is included in the packet or not.
     */
    function verifyMessageInclusion(
        bytes32 root_,
        bytes32 packedMessage_,
        bytes calldata proof_
    ) external returns (bool isIncluded);
}


// File contracts/utils/AccessRoles.sol

pragma solidity 0.8.19;

// contains role hashes used in socket dl for various different operations

// used to rescue funds
bytes32 constant RESCUE_ROLE = keccak256("RESCUE_ROLE");
// used to withdraw fees
bytes32 constant WITHDRAW_ROLE = keccak256("WITHDRAW_ROLE");
// used to trip switchboards
bytes32 constant TRIP_ROLE = keccak256("TRIP_ROLE");
// used to un trip switchboards
bytes32 constant UN_TRIP_ROLE = keccak256("UN_TRIP_ROLE");
// used by governance
bytes32 constant GOVERNANCE_ROLE = keccak256("GOVERNANCE_ROLE");
//used by executors which executes message at destination
bytes32 constant EXECUTOR_ROLE = keccak256("EXECUTOR_ROLE");
// used by transmitters who seal and propose packets in socket
bytes32 constant TRANSMITTER_ROLE = keccak256("TRANSMITTER_ROLE");
// used by switchboard watchers who work against transmitters
bytes32 constant WATCHER_ROLE = keccak256("WATCHER_ROLE");
// used by fee updaters responsible for updating fees at switchboards, transmit manager and execution manager
bytes32 constant FEES_UPDATER_ROLE = keccak256("FEES_UPDATER_ROLE");


// File lib/solmate/src/tokens/ERC20.sol

pragma solidity >=0.8.0;

/// @notice Modern and gas efficient ERC20 + EIP-2612 implementation.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC20.sol)
/// @author Modified from Uniswap (https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/UniswapV2ERC20.sol)
/// @dev Do not manually set balances without updating totalSupply, as the sum of all user balances must not exceed it.
abstract contract ERC20 {
    /*//////////////////////////////////////////////////////////////
                                 EVENTS
    //////////////////////////////////////////////////////////////*/

    event Transfer(address indexed from, address indexed to, uint256 amount);

    event Approval(address indexed owner, address indexed spender, uint256 amount);

    /*//////////////////////////////////////////////////////////////
                            METADATA STORAGE
    //////////////////////////////////////////////////////////////*/

    string public name;

    string public symbol;

    uint8 public immutable decimals;

    /*//////////////////////////////////////////////////////////////
                              ERC20 STORAGE
    //////////////////////////////////////////////////////////////*/

    uint256 public totalSupply;

    mapping(address => uint256) public balanceOf;

    mapping(address => mapping(address => uint256)) public allowance;

    /*//////////////////////////////////////////////////////////////
                            EIP-2612 STORAGE
    //////////////////////////////////////////////////////////////*/

    uint256 internal immutable INITIAL_CHAIN_ID;

    bytes32 internal immutable INITIAL_DOMAIN_SEPARATOR;

    mapping(address => uint256) public nonces;

    /*//////////////////////////////////////////////////////////////
                               CONSTRUCTOR
    //////////////////////////////////////////////////////////////*/

    constructor(
        string memory _name,
        string memory _symbol,
        uint8 _decimals
    ) {
        name = _name;
        symbol = _symbol;
        decimals = _decimals;

        INITIAL_CHAIN_ID = block.chainid;
        INITIAL_DOMAIN_SEPARATOR = computeDomainSeparator();
    }

    /*//////////////////////////////////////////////////////////////
                               ERC20 LOGIC
    //////////////////////////////////////////////////////////////*/

    function approve(address spender, uint256 amount) public virtual returns (bool) {
        allowance[msg.sender][spender] = amount;

        emit Approval(msg.sender, spender, amount);

        return true;
    }

    function transfer(address to, uint256 amount) public virtual returns (bool) {
        balanceOf[msg.sender] -= amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(msg.sender, to, amount);

        return true;
    }

    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual returns (bool) {
        uint256 allowed = allowance[from][msg.sender]; // Saves gas for limited approvals.

        if (allowed != type(uint256).max) allowance[from][msg.sender] = allowed - amount;

        balanceOf[from] -= amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(from, to, amount);

        return true;
    }

    /*//////////////////////////////////////////////////////////////
                             EIP-2612 LOGIC
    //////////////////////////////////////////////////////////////*/

    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual {
        require(deadline >= block.timestamp, "PERMIT_DEADLINE_EXPIRED");

        // Unchecked because the only math done is incrementing
        // the owner's nonce which cannot realistically overflow.
        unchecked {
            address recoveredAddress = ecrecover(
                keccak256(
                    abi.encodePacked(
                        "\x19\x01",
                        DOMAIN_SEPARATOR(),
                        keccak256(
                            abi.encode(
                                keccak256(
                                    "Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
                                ),
                                owner,
                                spender,
                                value,
                                nonces[owner]++,
                                deadline
                            )
                        )
                    )
                ),
                v,
                r,
                s
            );

            require(recoveredAddress != address(0) && recoveredAddress == owner, "INVALID_SIGNER");

            allowance[recoveredAddress][spender] = value;
        }

        emit Approval(owner, spender, value);
    }

    function DOMAIN_SEPARATOR() public view virtual returns (bytes32) {
        return block.chainid == INITIAL_CHAIN_ID ? INITIAL_DOMAIN_SEPARATOR : computeDomainSeparator();
    }

    function computeDomainSeparator() internal view virtual returns (bytes32) {
        return
            keccak256(
                abi.encode(
                    keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
                    keccak256(bytes(name)),
                    keccak256("1"),
                    block.chainid,
                    address(this)
                )
            );
    }

    /*//////////////////////////////////////////////////////////////
                        INTERNAL MINT/BURN LOGIC
    //////////////////////////////////////////////////////////////*/

    function _mint(address to, uint256 amount) internal virtual {
        totalSupply += amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(address(0), to, amount);
    }

    function _burn(address from, uint256 amount) internal virtual {
        balanceOf[from] -= amount;

        // Cannot underflow because a user's balance
        // will never be larger than the total supply.
        unchecked {
            totalSupply -= amount;
        }

        emit Transfer(from, address(0), amount);
    }
}


// File lib/solmate/src/utils/SafeTransferLib.sol

pragma solidity >=0.8.0;

/// @notice Safe ETH and ERC20 transfer library that gracefully handles missing return values.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SafeTransferLib.sol)
/// @dev Use with caution! Some functions in this library knowingly create dirty bits at the destination of the free memory pointer.
/// @dev Note that none of the functions in this library check that a token has code at all! That responsibility is delegated to the caller.
library SafeTransferLib {
    /*//////////////////////////////////////////////////////////////
                             ETH OPERATIONS
    //////////////////////////////////////////////////////////////*/

    function safeTransferETH(address to, uint256 amount) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Transfer the ETH and store if it succeeded or not.
            success := call(gas(), to, amount, 0, 0, 0, 0)
        }

        require(success, "ETH_TRANSFER_FAILED");
    }

    /*//////////////////////////////////////////////////////////////
                            ERC20 OPERATIONS
    //////////////////////////////////////////////////////////////*/

    function safeTransferFrom(
        ERC20 token,
        address from,
        address to,
        uint256 amount
    ) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0x23b872dd00000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), and(from, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "from" argument.
            mstore(add(freeMemoryPointer, 36), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
            mstore(add(freeMemoryPointer, 68), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 100 because the length of our calldata totals up like so: 4 + 32 * 3.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 100, 0, 32)
            )
        }

        require(success, "TRANSFER_FROM_FAILED");
    }

    function safeTransfer(
        ERC20 token,
        address to,
        uint256 amount
    ) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0xa9059cbb00000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
            )
        }

        require(success, "TRANSFER_FAILED");
    }

    function safeApprove(
        ERC20 token,
        address to,
        uint256 amount
    ) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0x095ea7b300000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
            )
        }

        require(success, "APPROVE_FAILED");
    }
}


// File contracts/libraries/RescueFundsLib.sol

pragma solidity 0.8.19;

error ZeroAddress();

/**
 * @title RescueFundsLib
 * @dev A library that provides a function to rescue funds from a contract.
 */

library RescueFundsLib {
    /**
     * @dev The address used to identify ETH.
     */
    address public constant ETH_ADDRESS =
        address(0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE);

    /**
     * @dev thrown when the given token address don't have any code
     */
    error InvalidTokenAddress();

    /**
     * @dev Rescues funds from a contract.
     * @param token_ The address of the token contract.
     * @param rescueTo_ The address of the user.
     * @param amount_ The amount of tokens to be rescued.
     */
    function rescueFunds(
        address token_,
        address rescueTo_,
        uint256 amount_
    ) internal {
        if (rescueTo_ == address(0)) revert ZeroAddress();

        if (token_ == ETH_ADDRESS) {
            SafeTransferLib.safeTransferETH(rescueTo_, amount_);
        } else {
            if (token_.code.length == 0) revert InvalidTokenAddress();
            SafeTransferLib.safeTransfer(ERC20(token_), rescueTo_, amount_);
        }
    }
}


// File contracts/decapacitors/SingleDecapacitor.sol

pragma solidity 0.8.19;




/**
 * @title SingleDecapacitor
 * @notice A decapacitor that verifies messages by checking if the packed message is equal to the root.
 * @dev This contract inherits from the `IDecapacitor` interface, which
 * defines the functions for verifying message inclusion.
 */
contract SingleDecapacitor is IDecapacitor, AccessControl {
    /**
     * @notice Initializes the SingleDecapacitor contract with an owner address.
     * @param owner_ The address of the contract owner
     */
    constructor(address owner_) AccessControl(owner_) {
        _grantRole(RESCUE_ROLE, owner_);
    }

    /**
     * @inheritdoc IDecapacitor
     * @dev Just checks if root equals packed message since each packet has single message.
     * @dev Proof is ignored in this capacitor.
     */
    function verifyMessageInclusion(
        bytes32 root_,
        bytes32 packedMessage_,
        bytes calldata /* proof */
    ) external pure override returns (bool isIncluded) {
        return root_ == packedMessage_;
    }

    /**
     * @notice Rescues funds from the contract if they are locked by mistake.
     * @param token_ The address of the token contract.
     * @param rescueTo_ The address where rescued tokens need to be sent.
     * @param amount_ The amount of tokens to be rescued.
     */
    function rescueFunds(
        address token_,
        address rescueTo_,
        uint256 amount_
    ) external onlyRole(RESCUE_ROLE) {
        RescueFundsLib.rescueFunds(token_, rescueTo_, amount_);
    }
}


// File contracts/interfaces/ITransmitManager.sol

pragma solidity 0.8.19;

/**
 * @title ITransmitManager
 * @dev The interface for a transmit manager contract
 */
interface ITransmitManager {
    /**
     * @notice Checks if a given transmitter is authorized to send transactions to the destination chain.
     * @param siblingSlug The unique identifier for the sibling chain.
     * @param digest The digest of the message being signed.
     * @param signature The signature of the message being signed.
     * @return The address of the transmitter and a boolean indicating whether the transmitter is authorized or not.
     */
    function checkTransmitter(
        uint32 siblingSlug,
        bytes32 digest,
        bytes calldata signature
    ) external view returns (address, bool);

    /**
     * @notice sets the transmission fee needed to transmit message to given `siblingSlug_`
     * @dev recovered address should add have feeUpdater role for `siblingSlug_`
     * @param nonce_ The incremental nonce to prevent signature replay
     * @param siblingSlug_ sibling id for which fee updater is registered
     * @param transmissionFees_ digest which is signed by transmitter
     * @param signature_ signature
     */
    function setTransmissionFees(
        uint256 nonce_,
        uint32 siblingSlug_,
        uint128 transmissionFees_,
        bytes calldata signature_
    ) external;

    /**
     * @notice receives fees from Execution manager
     * @dev this function can be used to keep track of fees received for each slug
     * @param siblingSlug_ sibling id for which fee updater is registered
     */
    function receiveFees(uint32 siblingSlug_) external payable;
}


// File contracts/interfaces/IExecutionManager.sol

pragma solidity 0.8.19;

/**
 * @title Execution Manager Interface
 * @dev This interface defines the functions for managing and executing transactions on external chains
 * @dev It is also responsible for collecting all the socket fees, which can then be pulled by others
 */
interface IExecutionManager {
    struct ExecutionFeesParam {
        // for calculating perGasCost * gasLimit
        uint80 perGasCost;
        // for calculating cost for executing payload (needed for rollups)
        uint80 perByteCost;
        // additional cost (differs based on chain)
        uint80 overhead;
    }

    /**
     * @notice Returns the executor of the packed message and whether the executor is authorized
     * @param packedMessage The message packed with payload, fees and config
     * @param sig The signature of the message
     * @return The address of the executor and a boolean indicating if the executor is authorized
     */
    function isExecutor(
        bytes32 packedMessage,
        bytes memory sig
    ) external view returns (address, bool);

    /**
     * @notice Pays the fees for executing a transaction on the external chain
     * @dev This function is payable and assumes the socket is going to send correct amount of fees.
     * @param minMsgGasLimit_ The minimum gas limit for the transaction
     * @param payloadSize_ The payload size in bytes
     * @param executionParams_ Extra params for execution
     * @param transmissionParams_ Extra params for transmission
     * @param siblingChainSlug_ Sibling chain identifier
     * @param switchboardFees_ fee charged by switchboard for processing transaction
     * @param verificationOverheadFees_ fee charged for verifying transaction
     * @param transmitManager_ The transmitManager address
     * @param switchboard_ The switchboard address
     * @param maxPacketLength_ The maxPacketLength for the capacitor
     */
    function payAndCheckFees(
        uint256 minMsgGasLimit_,
        uint256 payloadSize_,
        bytes32 executionParams_,
        bytes32 transmissionParams_,
        uint32 siblingChainSlug_,
        uint128 switchboardFees_,
        uint128 verificationOverheadFees_,
        address transmitManager_,
        address switchboard_,
        uint256 maxPacketLength_
    ) external payable returns (uint128, uint128);

    /**
     * @notice Returns the minimum fees required for executing a transaction on the external chain
     * @param minMsgGasLimit_ minMsgGasLimit_
     * @param siblingChainSlug_ The destination slug
     * @return The minimum fees required for executing the transaction
     */
    function getMinFees(
        uint256 minMsgGasLimit_,
        uint256 payloadSize_,
        bytes32 executionParams_,
        uint32 siblingChainSlug_
    ) external view returns (uint128);

    /**
     * @notice function for getting the minimum fees required for executing and transmitting a cross-chain transaction
     * @dev this function is called at source to calculate the execution cost.
     * @param payloadSize_ byte length of payload. Currently only used to check max length, later on will be used for fees calculation.
     * @param executionParams_ Can be used for providing extra information. Currently used for msgValue
     * @param siblingChainSlug_ Sibling chain identifier
     * @return minExecutionFee : Minimum fees required for executing the transaction
     */
    function getExecutionTransmissionMinFees(
        uint256 minMsgGasLimit_,
        uint256 payloadSize_,
        bytes32 executionParams_,
        bytes32 transmissionParams_,
        uint32 siblingChainSlug_,
        address transmitManager_
    ) external view returns (uint128, uint128);

    /**
     * @notice Updates the execution fees for an executor and message ID
     * @param executor The executor address
     * @param executionFees The execution fees to update
     * @param msgId The ID of the message
     */
    function updateExecutionFees(
        address executor,
        uint128 executionFees,
        bytes32 msgId
    ) external;

    /**
     * @notice updates the transmission fee
     * @param remoteChainSlug_ sibling chain identifier
     * @param transmitMinFees_ transmission fees collected
     */
    function setTransmissionMinFees(
        uint32 remoteChainSlug_,
        uint128 transmitMinFees_
    ) external;

    /**
     * @notice sets the minimum execution fees required for executing at `siblingChainSlug_`
     * @dev this function currently sets the price for a constant msg gas limit and payload size
     * @param nonce_ incremental id to prevent signature replay
     * @param siblingChainSlug_ sibling chain identifier
     * @param executionFees_ total fees where price in destination native token is converted to source native tokens
     * @param signature_ signature of fee updater
     */
    function setExecutionFees(
        uint256 nonce_,
        uint32 siblingChainSlug_,
        ExecutionFeesParam calldata executionFees_,
        bytes calldata signature_
    ) external;

    /**
     * @notice sets the min limit for msg value for `siblingChainSlug_`
     * @param nonce_ incremental id to prevent signature replay
     * @param siblingChainSlug_ sibling chain identifier
     * @param msgValueMinThreshold_ min msg value
     * @param signature_ signature of fee updater
     */
    function setMsgValueMinThreshold(
        uint256 nonce_,
        uint32 siblingChainSlug_,
        uint256 msgValueMinThreshold_,
        bytes calldata signature_
    ) external;

    /**
     * @notice sets the max limit for msg value for `siblingChainSlug_`
     * @param nonce_ incremental id to prevent signature replay
     * @param siblingChainSlug_ sibling chain identifier
     * @param msgValueMaxThreshold_ max msg value
     * @param signature_ signature of fee updater
     */
    function setMsgValueMaxThreshold(
        uint256 nonce_,
        uint32 siblingChainSlug_,
        uint256 msgValueMaxThreshold_,
        bytes calldata signature_
    ) external;

    /**
     * @notice sets the relative token price for `siblingChainSlug_`
     * @dev this function is expected to be called frequently to match the original prices
     * @param nonce_ incremental id to prevent signature replay
     * @param siblingChainSlug_ sibling chain identifier
     * @param relativeNativeTokenPrice_ relative price
     * @param signature_ signature of fee updater
     */
    function setRelativeNativeTokenPrice(
        uint256 nonce_,
        uint32 siblingChainSlug_,
        uint256 relativeNativeTokenPrice_,
        bytes calldata signature_
    ) external;

    /**
     * @notice called by socket while executing message to validate if the msg value provided is enough
     * @param executionParams_ a bytes32 string where first byte gives param type (if value is 0 or not)
     * and remaining bytes give the msg value needed
     * @param msgValue_ msg.value to be sent with inbound
     */
    function verifyParams(
        bytes32 executionParams_,
        uint256 msgValue_
    ) external view;

    /**
     * @notice withdraws switchboard fees from contract
     * @param siblingChainSlug_ withdraw fees corresponding to this slug
     * @param amount_ withdraw amount
     */
    function withdrawSwitchboardFees(
        uint32 siblingChainSlug_,
        address switchboard_,
        uint128 amount_
    ) external;

    /**
     * @dev this function gets the transmitManager address from the socket contract. If it is ever upgraded in socket,
     * @dev remove the fees from executionManager first, and then upgrade address at socket.
     * @notice withdraws transmission fees from contract
     * @param siblingChainSlug_ withdraw fees corresponding to this slug
     * @param amount_ withdraw amount
     */
    function withdrawTransmissionFees(
        uint32 siblingChainSlug_,
        uint128 amount_
    ) external;
}


// File contracts/interfaces/ISocket.sol

pragma solidity 0.8.19;


/**
 * @title ISocket
 * @notice An interface for a cross-chain communication contract
 * @dev This interface provides methods for transmitting and executing messages between chains,
 * connecting a plug to a remote chain and setting up switchboards for the message transmission
 * This interface also emits events for important operations such as message transmission, execution status,
 * and plug connection
 */
interface ISocket {
    /**
     * @notice A struct containing fees required for message transmission and execution
     * @param transmissionFees fees needed for transmission
     * @param switchboardFees fees needed by switchboard
     * @param executionFee fees needed for execution
     */
    struct Fees {
        uint128 transmissionFees;
        uint128 executionFee;
        uint128 switchboardFees;
    }

    /**
     * @title MessageDetails
     * @dev This struct defines the details of a message to be executed in a Decapacitor contract.
     */
    struct MessageDetails {
        // A unique identifier for the message.
        bytes32 msgId;
        // The fee to be paid for executing the message.
        uint256 executionFee;
        // The min amount of gas that can be used to execute the message.
        uint256 minMsgGasLimit;
        // The extra params which might provide msg value and additional info needed for message exec
        bytes32 executionParams;
        // The payload data to be executed in the message.
        bytes payload;
    }

    /**
     * @title ExecutionDetails
     * @dev This struct defines the execution details
     */
    struct ExecutionDetails {
        // packet id
        bytes32 packetId;
        // proposal count
        uint256 proposalCount;
        // gas limit needed to execute inbound
        uint256 executionGasLimit;
        // proof data required by the Decapacitor contract to verify the message's authenticity
        bytes decapacitorProof;
        // signature of executor
        bytes signature;
    }

    /**
     * @notice emits the status of message after inbound call
     * @param msgId msg id which is executed
     */
    event ExecutionSuccess(bytes32 msgId);

    /**
     * @notice emits the config set by a plug for a remoteChainSlug
     * @param plug address of plug on current chain
     * @param siblingChainSlug sibling chain slug
     * @param siblingPlug address of plug on sibling chain
     * @param inboundSwitchboard inbound switchboard (select from registered options)
     * @param outboundSwitchboard outbound switchboard (select from registered options)
     * @param capacitor capacitor selected based on outbound switchboard
     * @param decapacitor decapacitor selected based on inbound switchboard
     */
    event PlugConnected(
        address plug,
        uint32 siblingChainSlug,
        address siblingPlug,
        address inboundSwitchboard,
        address outboundSwitchboard,
        address capacitor,
        address decapacitor
    );

    /**
     * @notice registers a message
     * @dev Packs the message and includes it in a packet with capacitor
     * @param remoteChainSlug_ the remote chain slug
     * @param minMsgGasLimit_ the gas limit needed to execute the payload on remote
     * @param payload_ the data which is needed by plug at inbound call on remote
     */
    function outbound(
        uint32 remoteChainSlug_,
        uint256 minMsgGasLimit_,
        bytes32 executionParams_,
        bytes32 transmissionParams_,
        bytes calldata payload_
    ) external payable returns (bytes32 msgId);

    /**
     * @notice executes a message
     * @param executionDetails_ the packet details, proof and signature needed for message execution
     * @param messageDetails_ the message details
     */
    function execute(
        ISocket.ExecutionDetails calldata executionDetails_,
        ISocket.MessageDetails calldata messageDetails_
    ) external payable;

    /**
     * @notice seals data in capacitor for specific batchSize
     * @param batchSize_ size of batch to be sealed
     * @param capacitorAddress_ address of capacitor
     * @param signature_ signed Data needed for verification
     */
    function seal(
        uint256 batchSize_,
        address capacitorAddress_,
        bytes calldata signature_
    ) external payable;

    /**
     * @notice proposes a packet
     * @param packetId_ packet id
     * @param root_ root data
     * @param switchboard_ The address of switchboard for which this packet is proposed
     * @param signature_ signed Data needed for verification
     */
    function proposeForSwitchboard(
        bytes32 packetId_,
        bytes32 root_,
        address switchboard_,
        bytes calldata signature_
    ) external payable;

    /**
     * @notice sets the config specific to the plug
     * @param siblingChainSlug_ the sibling chain slug
     * @param siblingPlug_ address of plug present at sibling chain to call inbound
     * @param inboundSwitchboard_ the address of switchboard to use for receiving messages
     * @param outboundSwitchboard_ the address of switchboard to use for sending messages
     */
    function connect(
        uint32 siblingChainSlug_,
        address siblingPlug_,
        address inboundSwitchboard_,
        address outboundSwitchboard_
    ) external;

    /**
     * @notice deploy capacitor and decapacitor for a switchboard with a specified max packet length, sibling chain slug, and capacitor type.
     * @param siblingChainSlug_ The slug of the sibling chain that the switchboard is registered with.
     * @param maxPacketLength_ The maximum length of a packet allowed by the switchboard.
     * @param capacitorType_ The type of capacitor that the switchboard uses.
     * @param siblingSwitchboard_ The switchboard address deployed on `siblingChainSlug_`
     */
    function registerSwitchboardForSibling(
        uint32 siblingChainSlug_,
        uint256 maxPacketLength_,
        uint256 capacitorType_,
        address siblingSwitchboard_
    ) external returns (address capacitor, address decapacitor);

    /**
     * @notice Emits the sibling switchboard for given `siblingChainSlug_`.
     * @dev This function is expected to be only called by switchboard.
     * @dev the event emitted is tracked by transmitters to decide which switchboard a packet should be proposed on
     * @param siblingChainSlug_ The slug of the sibling chain
     * @param siblingSwitchboard_ The switchboard address deployed on `siblingChainSlug_`
     */
    function useSiblingSwitchboard(
        uint32 siblingChainSlug_,
        address siblingSwitchboard_
    ) external;

    /**
     * @notice Retrieves the packet id roots for a specified packet id.
     * @param packetId_ The packet id for which to retrieve the root.
     * @param proposalCount_ The proposal id for packetId_ for which to retrieve the root.
     * @param switchboard_ The address of switchboard for which this packet is proposed
     * @return The packet id roots for the specified packet id.
     */
    function packetIdRoots(
        bytes32 packetId_,
        uint256 proposalCount_,
        address switchboard_
    ) external view returns (bytes32);

    /**
     * @notice Retrieves the latest proposalCount for a packet id.
     * @return The proposal count for the specified packet id.
     */
    function proposalCount(bytes32 packetId_) external view returns (uint256);

    /**
     * @notice Retrieves the minimum fees required for a message with a specified gas limit and destination chain.
     * @param minMsgGasLimit_ The gas limit of the message.
     * @param remoteChainSlug_ The slug of the destination chain for the message.
     * @param plug_ The address of the plug through which the message is sent.
     * @return totalFees The minimum fees required for the specified message.
     */
    function getMinFees(
        uint256 minMsgGasLimit_,
        uint256 payloadSize_,
        bytes32 executionParams_,
        bytes32 transmissionParams_,
        uint32 remoteChainSlug_,
        address plug_
    ) external view returns (uint256 totalFees);

    /// return instance of transmit manager
    function transmitManager__() external view returns (ITransmitManager);

    /// return instance of execution manager
    function executionManager__() external view returns (IExecutionManager);
}


// File contracts/interfaces/IHasher.sol

pragma solidity 0.8.19;

/**
 * @title IHasher
 * @notice Interface for hasher contract that calculates the packed message
 */
interface IHasher {
    /**
     * @notice returns the bytes32 hash of the message packed
     * @param srcChainSlug src chain slug
     * @param srcPlug address of plug at source
     * @param dstChainSlug remote chain slug
     * @param dstPlug address of plug at remote
     * @param messageDetails contains message details, see ISocket for more details
     */
    function packMessage(
        uint32 srcChainSlug,
        address srcPlug,
        uint32 dstChainSlug,
        address dstPlug,
        ISocket.MessageDetails memory messageDetails
    ) external returns (bytes32);
}


// File contracts/interfaces/ISignatureVerifier.sol

pragma solidity 0.8.19;

/**
 * @title Signature Verifier
 * @notice Verifies the signatures and returns the address of signer recovered from the input signature or digest.
 */
interface ISignatureVerifier {
    /**
     * @notice returns the address of signer recovered from input signature and digest
     */
    function recoverSigner(
        bytes32 digest_,
        bytes memory signature_
    ) external pure returns (address signer);
}


// File contracts/interfaces/ISwitchboard.sol

pragma solidity 0.8.19;

/**
 * @title ISwitchboard
 * @dev The interface for a switchboard contract that is responsible for verification of packets between
 * different blockchain networks.
 */
interface ISwitchboard {
    /**
     * @notice Registers itself in Socket for given `siblingChainSlug_`.
     * @dev This function is expected to be only called by admin as it handles the capacitor config for given chain
     * @param siblingChainSlug_ The slug of the sibling chain to register switchboard with.
     * @param maxPacketLength_ The maximum length of a packet allowed by the switchboard.
     * @param capacitorType_ The type of capacitor that the switchboard uses.
     * @param initialPacketCount_ The packet count at the time of registering switchboard. Packets with packet count below this won't be allowed
     * @param siblingSwitchboard_ The switchboard address deployed on `siblingChainSlug_`
     */
    function registerSiblingSlug(
        uint32 siblingChainSlug_,
        uint256 maxPacketLength_,
        uint256 capacitorType_,
        uint256 initialPacketCount_,
        address siblingSwitchboard_
    ) external;

    /**
     * @notice Updates the sibling switchboard for given `siblingChainSlug_`.
     * @dev This function is expected to be only called by admin
     * @param siblingChainSlug_ The slug of the sibling chain to register switchboard with.
     * @param siblingSwitchboard_ The switchboard address deployed on `siblingChainSlug_`
     */
    function updateSibling(
        uint32 siblingChainSlug_,
        address siblingSwitchboard_
    ) external;

    /**
     * @notice Checks if a packet can be allowed to go through the switchboard.
     * @param root the packet root.
     * @param packetId The unique identifier for the packet.
     * @param proposalCount The unique identifier for a proposal for the packet.
     * @param srcChainSlug The unique identifier for the source chain of the packet.
     * @param proposeTime The time when the packet was proposed.
     * @return A boolean indicating whether the packet is allowed to go through the switchboard or not.
     */
    function allowPacket(
        bytes32 root,
        bytes32 packetId,
        uint256 proposalCount,
        uint32 srcChainSlug,
        uint256 proposeTime
    ) external view returns (bool);

    /**
     * @notice Retrieves the minimum fees required for the destination chain to process the packet.
     * @param dstChainSlug the unique identifier for the destination chain of the packet.
     * @return switchboardFee the switchboard fee required for the destination chain to process the packet.
     * @return verificationOverheadFees the verification fee required for the destination chain to process the packet.
     */
    function getMinFees(
        uint32 dstChainSlug
    )
        external
        view
        returns (uint128 switchboardFee, uint128 verificationOverheadFees);

    /**
     * @notice Receives the fees for processing of packet.
     * @param siblingChainSlug_ the chain slug of the sibling chain.
     */
    function receiveFees(uint32 siblingChainSlug_) external payable;

    /**
     * @notice Sets the minimum fees required for the destination chain to process the packet.
     * @param nonce_ the nonce of fee Updater to avoid replay.
     * @param dstChainSlug_ the unique identifier for the destination chain.
     * @param switchboardFees_ the switchboard fee required for the destination chain to process the packet.
     * @param verificationOverheadFees_ the verification fee required for the destination chain to process the packet.
     * @param signature_ the signature of the request.
     * @dev not important to override in all switchboards
     */
    function setFees(
        uint256 nonce_,
        uint32 dstChainSlug_,
        uint128 switchboardFees_,
        uint128 verificationOverheadFees_,
        bytes calldata signature_
    ) external;
}


// File contracts/interfaces/ICapacitor.sol

pragma solidity 0.8.19;

/**
 * @title ICapacitor
 * @dev Interface for a Capacitor contract that stores and manages messages in packets
 */
interface ICapacitor {
    /**
     * @notice adds the packed message to a packet
     * @dev this should be only executable by socket
     * @param packedMessage the message packed with payload, fees and config
     */
    function addPackedMessage(bytes32 packedMessage) external;

    /**
     * @notice returns the latest packet details which needs to be sealed
     * @return root root hash of the latest packet which is not yet sealed
     * @return packetCount latest packet id which is not yet sealed
     */
    function getNextPacketToBeSealed()
        external
        view
        returns (bytes32 root, uint64 packetCount);

    /**
     * @notice returns the root of packet for given id
     * @param id the id assigned to packet
     * @return root root hash corresponding to given id
     */
    function getRootByCount(uint64 id) external view returns (bytes32 root);

    /**
     * @notice returns the maxPacketLength
     * @return maxPacketLength of the capacitor
     */
    function getMaxPacketLength()
        external
        view
        returns (uint256 maxPacketLength);

    /**
     * @notice seals the packet
     * @dev indicates the packet is ready to be shipped and no more messages can be added now.
     * @dev this should be called by socket only
     * @param batchSize_ used with packet batching capacitors
     * @return root root hash of the packet
     * @return packetCount id of the packed sealed
     */
    function sealPacket(
        uint256 batchSize_
    ) external returns (bytes32 root, uint64 packetCount);
}


// File contracts/capacitors/BaseCapacitor.sol

pragma solidity 0.8.19;




/**
 * @title BaseCapacitor
 * @dev Abstract base contract for the Capacitors. Implements shared functionality and provides
 * access control.
 */
abstract contract BaseCapacitor is ICapacitor, AccessControl {
    /// address of socket
    address public immutable socket;

    /// an incrementing count for the next packet that is being created
    uint64 internal _nextPacketCount;

    /// tracks the count of next packet that will be sealed
    uint64 internal _nextSealCount;

    /// maps the packet count with the root hash of that packet
    mapping(uint64 => bytes32) internal _roots;

    // Error triggered when not called by socket
    error OnlySocket();

    /**
     * @dev Throws if called by any account other than the socket.
     */
    modifier onlySocket() {
        if (msg.sender != socket) revert OnlySocket();
        _;
    }

    /**
     * @dev Initializes the contract with the specified socket address.
     * @param socket_ The address of the socket contract.
     * @param owner_ The address of the owner of the capacitor contract.
     */
    constructor(address socket_, address owner_) AccessControl(owner_) {
        socket = socket_;
        _grantRole(RESCUE_ROLE, owner_);
    }

    /**
     * @dev Returns the count of the latest packet that finished filling.
     * @dev Returns 0 in case 0 or 1 packets are filled, hence this case should be considered by the caller
     * @return lastFilledPacket count of the latest packet.
     */
    function getLastFilledPacket()
        external
        view
        returns (uint256 lastFilledPacket)
    {
        return _nextPacketCount == 0 ? 0 : _nextPacketCount - 1;
    }

    /**
     * @dev Rescues funds from the contract.
     * @param token_ The address of the token to rescue.
     * @param rescueTo_ The address of the user to rescue tokens for.
     * @param amount_ The amount of tokens to rescue.
     */
    function rescueFunds(
        address token_,
        address rescueTo_,
        uint256 amount_
    ) external onlyRole(RESCUE_ROLE) {
        RescueFundsLib.rescueFunds(token_, rescueTo_, amount_);
    }
}


// File contracts/capacitors/SingleCapacitor.sol

pragma solidity 0.8.19;

/**
 * @title SingleCapacitor
 * @notice A capacitor that adds a single message to each packet.
 * @dev This contract inherits from the `BaseCapacitor` contract, which provides the
 * basic storage and common function implementations.
 */
contract SingleCapacitor is BaseCapacitor {
    // Error triggered when no new packet/message is there to be sealed
    error NoPendingPacket();

    /**
     * @notice emitted when a new message is added to a packet
     * @param packedMessage the message packed with payload, fees and config
     * @param packetCount an incremental id assigned to each new packet created on this capacitor
     * @param newRootHash Hash of full packet. Same as packedMessage since this capacitor has one message per packet.
     */
    event MessageAdded(
        bytes32 packedMessage,
        uint64 packetCount,
        bytes32 newRootHash
    );

    /**
     * @dev Initializes the contract with the specified socket address.
     * @param socket_ The address of the socket contract.
     * @param owner_ The address of the owner of the capacitor contract.
     */
    constructor(
        address socket_,
        address owner_
    ) BaseCapacitor(socket_, owner_) {}

    /**
     * @inheritdoc ICapacitor
     */
    function getMaxPacketLength() external pure override returns (uint256) {
        return 1;
    }

    /**
     * @inheritdoc ICapacitor
     */
    function addPackedMessage(
        bytes32 packedMessage_
    ) external override onlySocket {
        uint64 packetCount = _nextPacketCount++;
        _roots[packetCount] = packedMessage_;

        // as it is a single capacitor, here root and packed message are same
        emit MessageAdded(packedMessage_, packetCount, packedMessage_);
    }

    /**
     * @inheritdoc ICapacitor
     */
    function sealPacket(
        uint256
    ) external override onlySocket returns (bytes32, uint64) {
        uint64 packetCount = _nextSealCount++;
        if (_roots[packetCount] == bytes32(0)) revert NoPendingPacket();

        bytes32 root = _roots[packetCount];
        return (root, packetCount);
    }

    /**
     * @inheritdoc ICapacitor
     */
    function getNextPacketToBeSealed()
        external
        view
        override
        returns (bytes32, uint64)
    {
        uint64 toSeal = _nextSealCount;
        return (_roots[toSeal], toSeal);
    }

    /**
     * @dev Returns the root hash of the packet with the specified count.
     * @param count_ The count of the packet.
     * @return The root hash of the packet.
     */
    function getRootByCount(
        uint64 count_
    ) external view override returns (bytes32) {
        return _roots[count_];
    }
}


// File contracts/interfaces/IPlug.sol

pragma solidity 0.8.19;

/**
 * @title IPlug
 * @notice Interface for a plug contract that executes the message received from a source chain.
 */
interface IPlug {
    /**
     * @dev this should be only executable by socket
     * @notice executes the message received from source chain
     * @notice It is expected to have original sender checks in the destination plugs using payload
     * @param srcChainSlug_ chain slug of source
     * @param payload_ the data which is needed by plug at inbound call on remote
     */
    function inbound(
        uint32 srcChainSlug_,
        bytes calldata payload_
    ) external payable;
}


// File contracts/mocks/fee-updater/SocketSimulator.sol

pragma solidity 0.8.19;






interface ISimulatorUtils {
    function checkTransmitter(
        uint32 siblingSlug_,
        bytes32 digest_,
        bytes calldata signature_
    ) external view returns (address, bool);

    function updateExecutionFees(address, uint128, bytes32) external view;

    function verifyParams(
        bytes32 executionParams_,
        uint256 msgValue_
    ) external pure;

    function isExecutor(
        bytes32 packedMessage,
        bytes memory sig
    ) external view returns (address executor, bool isValidExecutor);
}

contract SocketSimulator is AccessControl {
    ISimulatorUtils public utils__;
    ISignatureVerifier public signatureVerifier__;
    IHasher public hasher__;
    SingleCapacitor public capacitor;

    bytes32 public immutable version;
    uint32 public immutable chainSlug;
    uint32 public immutable siblingChain;
    address constant plug = address(12345);

    mapping(address => uint32) public capacitorToSlug;

    mapping(bytes32 => uint256) public proposalCount;
    mapping(bytes32 => mapping(uint256 => mapping(address => bytes32)))
        public packetIdRoots;
    mapping(bytes32 => mapping(uint256 => mapping(address => uint256)))
        public rootProposedAt;
    mapping(bytes32 => bool) public messageExecuted;

    struct PlugConfig {
        // address of the sibling plug on the remote chain
        address siblingPlug;
        // capacitor instance for the outbound plug connection
        ICapacitor capacitor__;
        // decapacitor instance for the inbound plug connection
        IDecapacitor decapacitor__;
        // inbound switchboard instance for the plug connection
        ISwitchboard inboundSwitchboard__;
        // outbound switchboard instance for the plug connection
        ISwitchboard outboundSwitchboard__;
    }

    // plug => remoteChainSlug => (siblingPlug, capacitor__, decapacitor__, inboundSwitchboard__, outboundSwitchboard__)
    mapping(address => mapping(uint32 => PlugConfig)) internal _plugConfigs;

    error InvalidCapacitorAddress();
    error InvalidPacketId();
    error MessageAlreadyExecuted();
    error LowGasLimit();
    error ErrInSourceValidation();
    error PacketNotProposed();
    error NotExecutor();
    error VerificationFailed();
    error InvalidProof();

    event Sealed(
        address indexed transmitter,
        bytes32 indexed packetId,
        uint256 batchSize,
        bytes32 root,
        bytes signature
    );
    event PacketProposed(
        address indexed transmitter,
        bytes32 indexed packetId,
        uint256 proposalCount,
        bytes32 root,
        address switchboard
    );
    event ExecutionSuccess(bytes32 msgId);

    constructor(
        uint32 chainSlug_,
        uint32 siblingChainSlug_,
        address hasher_,
        address signatureVerifier_,
        string memory version_
    ) AccessControl(msg.sender) {
        chainSlug = chainSlug_;
        siblingChain = siblingChainSlug_;
        version = keccak256(bytes(version_));
        hasher__ = IHasher(hasher_);
        signatureVerifier__ = ISignatureVerifier(signatureVerifier_);
    }

    function setup(address switchboard_, address utils_) external onlyOwner {
        utils__ = ISimulatorUtils(utils_);

        bytes32 packedMessage = hasher__.packMessage(
            chainSlug,
            plug,
            siblingChain,
            plug,
            ISocket.MessageDetails(
                bytes32(
                    (uint256(chainSlug) << 224) |
                        (uint256(uint160(plug)) << 64) |
                        0
                ),
                0,
                12000,
                bytes32(0),
                bytes("")
            )
        );

        capacitor = new SingleCapacitor(address(this), msg.sender);
        PlugConfig storage plugConfig = _plugConfigs[plug][siblingChain];

        capacitorToSlug[address(capacitor)] = siblingChain;
        plugConfig.siblingPlug = plug;
        plugConfig.capacitor__ = capacitor;
        plugConfig.decapacitor__ = new SingleDecapacitor(msg.sender);
        plugConfig.inboundSwitchboard__ = ISwitchboard(switchboard_);
        plugConfig.outboundSwitchboard__ = ISwitchboard(switchboard_);
        plugConfig.capacitor__.addPackedMessage(packedMessage);

        packetIdRoots[_encodePacketId(address(capacitor), 0)][0][
            switchboard_
        ] = bytes32("random");
    }

    /**
     * @notice seals data in capacitor for specific batchSize
     * @param batchSize_ size of batch to be sealed
     * @param capacitorAddress_ address of capacitor
     * @param signature_ signed Data needed for verification
     */
    function seal(
        uint256 batchSize_,
        address capacitorAddress_,
        bytes calldata signature_
    ) external payable onlyOwner {
        uint32 siblingChainSlug = capacitorToSlug[capacitorAddress_];
        if (siblingChain == 0) revert InvalidCapacitorAddress();

        (bytes32 root, uint64 packetCount) = ICapacitor(capacitorAddress_)
            .sealPacket(batchSize_);

        bytes32 packetId = _encodePacketId(capacitorAddress_, packetCount);
        (address transmitter, bool isTransmitter) = utils__.checkTransmitter(
            siblingChain,
            keccak256(abi.encode(version, siblingChain, packetId, root)),
            signature_
        );

        if (siblingChain == 0) revert InvalidCapacitorAddress();
        emit Sealed(transmitter, packetId, batchSize_, root, signature_);
    }

    function proposeForSwitchboard(
        bytes32 packetId_,
        bytes32 root_,
        address switchboard_,
        bytes calldata signature_
    ) external payable onlyOwner {
        if (packetId_ == bytes32(0)) revert InvalidPacketId();

        (address transmitter, bool isTransmitter) = utils__.checkTransmitter(
            _decodeChainSlug(packetId_),
            keccak256(abi.encode(version, chainSlug, packetId_, root_)),
            signature_
        );

        if (packetId_ == bytes32(0)) revert InvalidPacketId();

        packetIdRoots[packetId_][proposalCount[packetId_]][
            switchboard_
        ] = root_;
        rootProposedAt[packetId_][proposalCount[packetId_]][
            switchboard_
        ] = block.timestamp;

        emit PacketProposed(
            transmitter,
            packetId_,
            proposalCount[packetId_]++,
            root_,
            switchboard_
        );
    }

    function execute(
        ISocket.ExecutionDetails calldata executionDetails_,
        ISocket.MessageDetails calldata messageDetails_
    ) external payable onlyOwner {
        // make sure message is not executed already
        if (messageExecuted[messageDetails_.msgId])
            revert MessageAlreadyExecuted();

        // update state to make sure no reentrancy
        messageExecuted[messageDetails_.msgId] = true;

        // make sure caller is calling with right gas limits
        // we also make sure to give executors the ability to execute with higher gas limits
        // than the minimum required
        if (
            executionDetails_.executionGasLimit < messageDetails_.minMsgGasLimit
        ) revert LowGasLimit();

        if (executionDetails_.packetId == bytes32(0)) revert InvalidPacketId();

        // extract chain slug from msgID
        uint32 remoteSlug = _decodeChainSlug(messageDetails_.msgId);

        // make sure packet and msg are for the same chain
        if (_decodeChainSlug(executionDetails_.packetId) != remoteSlug)
            revert ErrInSourceValidation();

        // extract plug address from msgID
        address localPlug = _decodePlug(messageDetails_.msgId);

        // fetch required vars from plug config
        PlugConfig memory plugConfig;
        plugConfig.decapacitor__ = _plugConfigs[localPlug][remoteSlug]
            .decapacitor__;
        plugConfig.siblingPlug = _plugConfigs[localPlug][remoteSlug]
            .siblingPlug;
        plugConfig.inboundSwitchboard__ = _plugConfigs[localPlug][remoteSlug]
            .inboundSwitchboard__;

        // fetch packet root
        bytes32 packetRoot = packetIdRoots[executionDetails_.packetId][
            executionDetails_.proposalCount
        ][address(plugConfig.inboundSwitchboard__)];
        // if (packetRoot == bytes32(0)) revert PacketNotProposed();

        // create packed message
        bytes32 packedMessage = hasher__.packMessage(
            remoteSlug,
            plugConfig.siblingPlug,
            chainSlug,
            localPlug,
            messageDetails_
        );

        // make sure caller is executor
        (address executor, bool isValidExecutor) = utils__.isExecutor(
            packedMessage,
            executionDetails_.signature
        );
        if (!isValidExecutor) revert NotExecutor();

        // finally make sure executor params were respected by the executor
        utils__.verifyParams(messageDetails_.executionParams, msg.value);

        // verify message was part of the packet and
        // authenticated by respective switchboard

        _verify(
            executionDetails_.packetId,
            executionDetails_.proposalCount,
            remoteSlug,
            packedMessage,
            packetRoot,
            plugConfig,
            executionDetails_.decapacitorProof
        );

        // execute message
        _execute(
            executor,
            localPlug,
            remoteSlug,
            executionDetails_.executionGasLimit,
            messageDetails_
        );
    }

    ////////////////////////////////////////////////////////
    ////////////////// INTERNAL FUNCS //////////////////////
    ////////////////////////////////////////////////////////

    function _verify(
        bytes32 packetId_,
        uint256 proposalCount_,
        uint32 remoteChainSlug_,
        bytes32 packedMessage_,
        bytes32 packetRoot_,
        PlugConfig memory plugConfig_,
        bytes memory decapacitorProof_
    ) internal {
        // NOTE: is the the first un-trusted call in the system, another one is Plug.inbound
        if (
            !ISwitchboard(plugConfig_.inboundSwitchboard__).allowPacket(
                packetRoot_,
                packetId_,
                proposalCount_,
                remoteChainSlug_,
                rootProposedAt[packetId_][proposalCount_][
                    address(plugConfig_.inboundSwitchboard__)
                ]
            )
        ) revert VerificationFailed();

        if (
            !plugConfig_.decapacitor__.verifyMessageInclusion(
                packetRoot_,
                packetRoot_,
                decapacitorProof_
            )
        ) revert InvalidProof();
    }

    /**
     * This function assumes localPlug_ will have code while executing. As the message
     * execution failure is not blocking the system, it is not necessary to check if
     * code exists in the given address.
     */
    function _execute(
        address executor_,
        address localPlug_,
        uint32 remoteChainSlug_,
        uint256 executionGasLimit_,
        ISocket.MessageDetails memory messageDetails_
    ) internal {
        // NOTE: external un-trusted call
        // IPlug(localPlug_).inbound{gas: executionGasLimit_, value: msg.value}(
        //     remoteChainSlug_,
        //     messageDetails_.payload
        // );

        utils__.updateExecutionFees(
            executor_,
            uint128(messageDetails_.executionFee),
            messageDetails_.msgId
        );
        emit ExecutionSuccess(messageDetails_.msgId);
    }

    /**
     * @dev Decodes the plug address from a given message id.
     * @param id_ The ID of the msg to decode the plug from.
     * @return plug_ The address of sibling plug decoded from the message ID.
     */
    function _decodePlug(bytes32 id_) internal pure returns (address plug_) {
        plug_ = address(uint160(uint256(id_) >> 64));
    }

    /**
     * @dev Decodes the chain ID from a given packet/message ID.
     * @param id_ The ID of the packet/msg to decode the chain slug from.
     * @return chainSlug_ The chain slug decoded from the packet/message ID.
     */
    function _decodeChainSlug(
        bytes32 id_
    ) internal pure returns (uint32 chainSlug_) {
        chainSlug_ = uint32(uint256(id_) >> 224);
    }

    function _encodePacketId(
        address capacitorAddress_,
        uint64 packetCount_
    ) internal view returns (bytes32) {
        return
            bytes32(
                (uint256(chainSlug) << 224) |
                    (uint256(uint160(capacitorAddress_)) << 64) |
                    packetCount_
            );
    }
}