refactor: update comments and minimum deposit logic

Author: passandscore

contracts/contracts/core/GasTankManager.sol

@@ -8,44 +8,43 @@ import {GasTankManagerStorage} from "./GasTankManagerStorage.sol";
 import {Errors} from "../utils/Errors.sol";
 
 /// @title GasTankManager
-/// @notice Coordinates on-demand ETH bridging so EOA gas tank balances stay funded for mev-commit transactions.
-/// @dev The RPC provider manages EOA gas tank balances on the Mev Commit chain.
+/// @notice Coordinates on-demand ETH Transfers to the RPC Service for EOA custodial gas tanks.
 /// @dev Flow overview:
-/// - EOA (L1)
-///   - Authorizes and sets this contract as a delegate against its own EOA address. (ERC-7702)
-///   - Calls `sendMinimumDeposit` to send the initial ETH funds to their gas tank on the Mev Commit chain.
-/// - Provider (mev-commit)
-///   - Triggers a top-up via `topUpGasTank` when the gas tank balance cannot cover the next mev-commit transaction. This transfer amount is always the difference
-///   between the `minDeposit` and the current balance of this contract. The provider is the only one who can trigger a top-up.
-///   - These funds are then transferred to the EOA gas tank on the Mev Commit chain.
-///   - When a mev-commit transaction is made, the provider deducts the amount needed from the EOA's gas tank.
+/// - EOA (Prerequisites for use)
+///   - Authorizes and sets this contract as a delegate against its own EOA address. (ERC-7702 compliant)
+///   - Sends the initial minimum deposit via `initializeGasTank` to the RPC Service.
+/// - RPC Service
+///   - Triggers `topUpGasTank`, transferring the `minDeposit` when the gas tank requires funding.
+///   - These funds are then transferred to the RPC Service's custodial gas tank.
 contract GasTankManager is IGasTankManager, GasTankManagerStorage, Ownable2StepUpgradeable, UUPSUpgradeable {
     /// @notice Restricts calls to those triggered internally via `onlyThisEOA`.
     modifier onlyThisEOA() {
         require(msg.sender == address(this), NotThisEOA(msg.sender, address(this)));
         _;
     }
 
+    modifier isValidCaller() {
+        require(msg.sender == address(this) || msg.sender == owner(), NotValidCaller(msg.sender));
+        _;
+    }
+
     /// @notice Locks the implementation upon deployment.
-    /// @dev See https://docs.openzeppelin.com/upgrades-plugins/writing-upgradeable#initializing-the-implementation-contract
     /// @custom:oz-upgrades-unsafe-allow constructor
     constructor() {
         _disableInitializers();
     }
 
-    /// @notice Accepts direct ETH deposits and forwards them to the provider.
-    receive() external payable {
-        _sendFundsToProvider(msg.value);
-    }
+    /// @notice Accepts direct ETH deposits.
+    receive() external payable {}
 
     /// @notice Reverts on any call data to keep the interface surface narrow.
     fallback() external payable {
         revert Errors.InvalidFallback();
     }
 
-    /// @notice Initializes ownership and baseline deposit requirement.
-    /// @param _owner EOA managed by the RPC provider.
-    /// @param _minDeposit Initial deposit requirement in wei.
+    /// @notice Initializes ownership and the minimum deposit requirement.
+    /// @param _owner EOA managed by the RPC Service.
+    /// @param _minDeposit Minimum deposit requirement.
     function initialize(address _owner, uint256 _minDeposit) external initializer {
         minDeposit = _minDeposit;
         __Ownable_init(_owner);
@@ -59,55 +58,34 @@ contract GasTankManager is IGasTankManager, GasTankManagerStorage, Ownable2StepU
     }
 
     /// @inheritdoc IGasTankManager
-    function topUpGasTank(uint256 _gasTankBalance) external onlyOwner {
-        uint256 minDeposit_ = minDeposit;
-        uint256 available = address(this).balance;
-        uint256 needed = minDeposit_ - _gasTankBalance;
-
-        _validateTopUp(_gasTankBalance, available, needed, minDeposit_);
-
-        _sendFundsToProvider(needed);
-        emit GasTankToppedUp(needed);
+    function topUpGasTank() external onlyOwner {
+        _sendFundsToProvider(minDeposit);
     }
 
     /// @inheritdoc IGasTankManager
-    function fundGasTank() external payable {
-        _sendFundsToProvider(msg.value);
+    function initializeGasTank() external onlyThisEOA {
+        _sendFundsToProvider(minDeposit);
     }
 
     /// @inheritdoc IGasTankManager
-    function sendMinimumDeposit() external payable onlyThisEOA {
-        require(msg.value >= minDeposit, InsufficientFundsSent(msg.value, minDeposit));
-        _sendFundsToProvider(minDeposit);
+    function fundGasTank() external payable isValidCaller {
+        _sendFundsToProvider(msg.value);
     }
 
-    /// @notice Restricts upgradeability to the owner.
-    /// @dev See https://docs.openzeppelin.com/upgrades-plugins/foundry/api/upgrades
     /// solhint-disable-next-line no-empty-blocks
     function _authorizeUpgrade(address) internal override onlyOwner {}
 
-    /// @notice Forwards ETH to the configured provider address.
-    /// @dev Reverts when the provider rejects the transfer.
-    /// @param _amount Amount of wei to transfer.
+    /// @notice Forwards ETH to the rpcService.
+    /// @param _amount Gas tank top-up amount.
     function _sendFundsToProvider(uint256 _amount) internal {
-        address provider = owner();
-        require(provider != address(0), ProviderNotSet(provider));
+        address rpcService = owner();
 
-        (bool success,) = provider.call{value: _amount}("");
-        require(success, GasTankTopUpFailed(provider, _amount));
-    }
+        require(rpcService != address(0), ProviderNotSet(rpcService));
+        require(_amount > 0, InvalidAmount());
+
+        (bool success,) = rpcService.call{value: _amount}("");
+        require(success, GasTankTopUpFailed(rpcService, _amount));
 
-    /// @notice Validates the proposed refill before forwarding funds.
-    /// @dev Applies guardrails to protect configured thresholds.
-    /// @param _gasTankBalance Current gas tank balance.
-    /// @param _available Current contract (EOA) balance.
-    /// @param _needed Amount required to reach the `minDeposit`.
-    /// @param _minDeposit Minimum deposit requirement in wei.
-    function _validateTopUp(uint256 _gasTankBalance, uint256 _available, uint256 _needed, uint256 _minDeposit)
-        internal
-        view
-    {
-        require(_gasTankBalance < _minDeposit, GasTankBalanceIsSufficient(_gasTankBalance, _minDeposit));
-        require(_available > _needed, InsufficientEOABalance(address(this), _available, _needed));
+        emit GasTankToppedUp(address(this), msg.sender, _amount);
     }
 }

contracts/contracts/interfaces/IGasTankManager.sol

@@ -10,18 +10,19 @@ interface IGasTankManager {
     event MinimumDepositSet(uint256 indexed minDeposit);
 
     /// @dev Event to log successful gas tank top up.
-    event GasTankToppedUp(uint256 indexed transferAmount);
+    event GasTankToppedUp(address indexed smartAccount, address indexed caller, uint256 indexed amount);
 
     /// @notice Raised when a call expected from the contract itself is not.
     /// @param msgSender Address that invoked the call.
     /// @param thisAddress Address of the contract guard.
     error NotThisEOA(address msgSender, address thisAddress);
 
-    /// @notice Raised when the contract balance cannot satisfy a refill.
-    /// @param eoaAddress L1 EOA address.
-    /// @param available Wei currently available on the L1 EOA address.
-    /// @param needed Wei required to meet the minimum deposit requirement.
-    error InsufficientEOABalance(address eoaAddress, uint256 available, uint256 needed);
+    /// @notice Raised when an invalid caller is detected.
+    /// @param caller Address that invoked the call.
+    error NotValidCaller(address caller);
+
+    /// @notice Raised when an invalid amount is detected.
+    error InvalidAmount();
 
     /// @notice Raised when forwarding funds to the provider reverts.
     /// @param rpcProvider Destination address for the transfer.
@@ -33,11 +34,6 @@ interface IGasTankManager {
     /// @param minDeposit Minimum deposit requirement.
     error GasTankBalanceIsSufficient(uint256 currentBalance, uint256 minDeposit);
 
-    /// @notice Raised when the initial minimum deposit is not sufficient.
-    /// @param sentAmount Amount of wei sent.
-    /// @param requiredAmount Amount of wei required.
-    error InsufficientFundsSent(uint256 sentAmount, uint256 requiredAmount);
-
     /// @notice Raised when the provider address is not set.
     /// @param provider Provider address.
     error ProviderNotSet(address provider);
@@ -47,18 +43,14 @@ interface IGasTankManager {
     /// @dev Only the owner can call this function.
     function setMinimumDeposit(uint256 minDeposit) external;
 
-    /// @notice Requests a top-up when the gas tank's balance is below the minimum deposit requirement.
-    /// @param gasTankBalance Balance that the provider currently holds on the gas tank.
-    /// @dev Only the owner can call this function.
-    /// @dev Reverts if the current gas tank balance is greater than or equal to the minimum deposit requirement.
-    /// @dev Reverts if the contract balance is less than the amount needed to reach the minimum deposit requirement.
-    /// @dev Always transfer the difference between the minimum deposit requirement and the current gas tank balance.
-    function topUpGasTank(uint256 gasTankBalance) external;
+    /// @notice RPC requested top-up of the gas tank.
+    /// @dev Always transfers the minimum deposit requirement.
+    function topUpGasTank() external;
 
-    /// @notice Allows anyone to contribute funds. Forwards them to the provider immediately.
+    /// @notice Allows anyone to fund the gas tank.
     function fundGasTank() external payable;
 
-    /// @notice Sets the initial minimum deposit requirement. Forwards them to the provider immediately.
-    /// @dev Reverts if the amount sent is less than the baseline deposit.
-    function sendMinimumDeposit() external payable;
+    /// @notice Initializes the gas tank with the minimum deposit.
+    /// @dev Only the EOA can call this function.
+    function initializeGasTank() external;
 }