feat: transact flow (#45)

* WIP: feat: transact flow

* fix: update 1559 fields

* option: handling enter + transact

* feat: add option to specify ether recipient

* handle zero value, docs

Author: anna-carroll

.gas-snapshot

@@ -1,6 +1,6 @@
-ZenithTest:test_badSequence() (gas: 60199)
-ZenithTest:test_badSignature() (gas: 66867)
-ZenithTest:test_blockExpired() (gas: 55430)
-ZenithTest:test_notSequencer() (gas: 58572)
-ZenithTest:test_onePerBlock() (gas: 104311)
-ZenithTest:test_submitBlock() (gas: 88457)
+ZenithTest:test_badSequence() (gas: 60268)
+ZenithTest:test_badSignature() (gas: 66936)
+ZenithTest:test_blockExpired() (gas: 55499)
+ZenithTest:test_notSequencer() (gas: 58618)
+ZenithTest:test_onePerBlock() (gas: 104426)
+ZenithTest:test_submitBlock() (gas: 88526)

src/Passage.sol

@@ -20,6 +20,17 @@ contract Passage {
     /// @param amount - The amount of Ether entering the rollup.
     event Enter(uint256 indexed rollupChainId, address indexed rollupRecipient, uint256 amount);
 
+    /// @notice Emitted to send a special transaction to the rollup.
+    event Transact(
+        uint256 indexed rollupChainId,
+        address indexed sender,
+        address indexed to,
+        bytes data,
+        uint256 value,
+        uint256 gas,
+        uint256 maxFeePerGas
+    );
+
     /// @notice Emitted when the admin withdraws tokens from the contract.
     event Withdrawal(address indexed token, address indexed recipient, uint256 amount);
 
@@ -45,15 +56,64 @@ contract Passage {
     /// @param rollupRecipient - The recipient of the Ether on the rollup.
     /// @custom:emits Enter indicating the amount of Ether to mint on the rollup & its recipient.
     function enter(uint256 rollupChainId, address rollupRecipient) public payable {
+        if (msg.value == 0) return;
         emit Enter(rollupChainId, rollupRecipient, msg.value);
     }
 
     /// @notice Allows native Ether to enter the default rollup.
-    /// @dev see `enter` above for docs.
+    /// @dev see `enter` for docs.
     function enter(address rollupRecipient) external payable {
         enter(defaultRollupChainId, rollupRecipient);
     }
 
+    /// @notice Allows a special transaction to be sent to the rollup with sender == L1 msg.sender.
+    /// @dev Transaction is processed after normal rollup block execution.
+    /// @dev See `enterTransact` for docs.
+    function transact(
+        uint256 rollupChainId,
+        address to,
+        bytes calldata data,
+        uint256 value,
+        uint256 gas,
+        uint256 maxFeePerGas
+    ) public payable {
+        enterTransact(rollupChainId, msg.sender, to, data, value, gas, maxFeePerGas);
+    }
+
+    /// @dev See `transact` for docs.
+    function transact(address to, bytes calldata data, uint256 value, uint256 gas, uint256 maxFeePerGas)
+        external
+        payable
+    {
+        enterTransact(defaultRollupChainId, msg.sender, to, data, value, gas, maxFeePerGas);
+    }
+
+    /// @notice Send Ether on the rollup, send a special transaction to be sent to the rollup with sender == L1 msg.sender.
+    /// @dev Enter and Transact are processed after normal rollup block execution.
+    /// @dev See `enter` for Enter docs.
+    /// @param rollupChainId - The rollup chain to send the transaction to.
+    /// @param etherRecipient - The recipient of the ether.
+    /// @param to - The address to call on the rollup.
+    /// @param data - The data to send to the rollup.
+    /// @param value - The amount of Ether to send on the rollup.
+    /// @param gas - The gas limit for the transaction.
+    /// @param maxFeePerGas - The maximum fee per gas for the transaction (per EIP-1559).
+    /// @custom:emits Transact indicating the transaction to mine on the rollup.
+    function enterTransact(
+        uint256 rollupChainId,
+        address etherRecipient,
+        address to,
+        bytes calldata data,
+        uint256 value,
+        uint256 gas,
+        uint256 maxFeePerGas
+    ) public payable {
+        // if msg.value is attached, Enter
+        enter(rollupChainId, etherRecipient);
+        // emit Transact event
+        emit Transact(rollupChainId, msg.sender, to, data, value, gas, maxFeePerGas);
+    }
+
     /// @notice Allows the admin to withdraw ETH or ERC20 tokens from the contract.
     /// @dev Only the admin can call this function.
     function withdraw(address token, address recipient, uint256 amount) external {