refactor: reorganize contracts (#68)

script/Zenith.s.sol

@@ -1,11 +1,14 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.24;
 
-import {Script} from "forge-std/Script.sol";
+// deploy contracts
 import {Zenith} from "../src/Zenith.sol";
-import {Passage, RollupPassage} from "../src/Passage.sol";
 import {Transactor} from "../src/Transact.sol";
-import {HostOrders, RollupOrders} from "../src/Orders.sol";
+import {HostOrders, RollupOrders} from "../src/orders/Orders.sol";
+import {Passage} from "../src/passage/Passage.sol";
+import {RollupPassage} from "../src/passage/RollupPassage.sol";
+// utils
+import {Script} from "forge-std/Script.sol";
 
 contract ZenithScript is Script {
     // deploy:

src/Transact.sol

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.24;
 
-import {Passage} from "./Passage.sol";
+import {Passage} from "./passage/Passage.sol";
 
 /// @notice A contract deployed to Host chain that enables transactions from L1 to be sent on an L2.
 contract Transactor {

src/UsesPermit2.sol

@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.24;
+
+import {IOrders} from "./orders/IOrders.sol";
+import {ISignatureTransfer} from "permit2/src/interfaces/ISignatureTransfer.sol";
+
+abstract contract UsesPermit2 {
+    /// @param permit - the permit2 single token transfer details. includes a `deadline` and an unordered `nonce`.
+    /// @param signer - the signer of the permit2 info; the owner of the tokens.
+    /// @param signature - the signature over the permit + witness.
+    struct Permit2 {
+        ISignatureTransfer.PermitTransferFrom permit;
+        address owner;
+        bytes signature;
+    }
+
+    /// @param permit - the permit2 batch token transfer details. includes a `deadline` and an unordered `nonce`.
+    /// @param signer - the signer of the permit2 info; the owner of the tokens.
+    /// @param signature - the signature over the permit + witness.
+    struct Permit2Batch {
+        ISignatureTransfer.PermitBatchTransferFrom permit;
+        address owner;
+        bytes signature;
+    }
+
+    /// @notice Struct to hold the pre-hashed witness field and the witness type string.
+    struct Witness {
+        bytes32 witnessHash;
+        string witnessTypeString;
+    }
+
+    /// @notice The Permit2 contract address.
+    address immutable permit2Contract;
+
+    constructor(address _permit2) {
+        permit2Contract = _permit2;
+    }
+}

src/orders/OrderDestination.sol

@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.24;
+
+import {OrdersPermit2} from "./OrdersPermit2.sol";
+import {IOrders} from "./IOrders.sol";
+import {IERC20} from "openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";
+
+/// @notice Contract capable of processing fulfillment of intent-based Orders.
+abstract contract OrderDestination is IOrders, OrdersPermit2 {
+    /// @notice Emitted when Order Outputs are sent to their recipients.
+    /// @dev NOTE that here, Output.chainId denotes the *origin* chainId.
+    event Filled(Output[] outputs);
+
+    /// @notice Fill any number of Order(s), by transferring their Output(s).
+    /// @dev Filler may aggregate multiple Outputs with the same (`chainId`, `recipient`, `token`) into a single Output with the summed `amount`.
+    /// @dev NOTE that here, Output.chainId denotes the *origin* chainId.
+    /// @param outputs - The Outputs to be transferred.
+    /// @custom:emits Filled
+    function fill(Output[] memory outputs) external payable {
+        // transfer outputs
+        _transferOutputs(outputs);
+
+        // emit
+        emit Filled(outputs);
+    }
+
+    /// @notice Fill any number of Order(s), by transferring their Output(s) via permit2 signed batch transfer.
+    /// @dev Can only provide ERC20 tokens as Outputs.
+    /// @dev Filler may aggregate multiple Outputs with the same (`chainId`, `recipient`, `token`) into a single Output with the summed `amount`.
+    /// @dev the permit2 signer is the Filler providing the Outputs.
+    /// @dev the permit2 `permitted` tokens MUST match provided Outputs.
+    /// @dev Filler MUST submit `fill` and `intitiate` within an atomic bundle.
+    /// @dev NOTE that here, Output.chainId denotes the *origin* chainId.
+    /// @param outputs - The Outputs to be transferred. signed over via permit2 witness.
+    /// @param permit2 - the permit2 details, signer, and signature.
+    /// @custom:emits Filled
+    function fillPermit2(Output[] memory outputs, OrdersPermit2.Permit2Batch calldata permit2) external {
+        // transfer all tokens to the Output recipients via permit2 (includes check on nonce & deadline)
+        _permitWitnessTransferFrom(
+            outputWitness(outputs), _fillTransferDetails(outputs, permit2.permit.permitted), permit2
+        );
+
+        // emit
+        emit Filled(outputs);
+    }
+
+    /// @notice Transfer the Order Outputs to their recipients.
+    function _transferOutputs(Output[] memory outputs) internal {
+        uint256 value = msg.value;
+        for (uint256 i; i < outputs.length; i++) {
+            if (outputs[i].token == address(0)) {
+                // this line should underflow if there's an attempt to spend more ETH than is attached to the transaction
+                value -= outputs[i].amount;
+                payable(outputs[i].recipient).transfer(outputs[i].amount);
+            } else {
+                IERC20(outputs[i].token).transferFrom(msg.sender, outputs[i].recipient, outputs[i].amount);
+            }
+        }
+    }
+}

src/Orders.sol → src/orders/OrderOrigin.sol

@@ -1,64 +1,10 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.24;
 
-import {OrdersPermit2, UsesPermit2} from "./permit2/UsesPermit2.sol";
-import {IOrders} from "./interfaces/IOrders.sol";
+import {OrdersPermit2} from "./OrdersPermit2.sol";
+import {IOrders} from "./IOrders.sol";
 import {IERC20} from "openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";
 
-/// @notice Contract capable of processing fulfillment of intent-based Orders.
-abstract contract OrderDestination is IOrders, OrdersPermit2 {
-    /// @notice Emitted when Order Outputs are sent to their recipients.
-    /// @dev NOTE that here, Output.chainId denotes the *origin* chainId.
-    event Filled(Output[] outputs);
-
-    /// @notice Fill any number of Order(s), by transferring their Output(s).
-    /// @dev Filler may aggregate multiple Outputs with the same (`chainId`, `recipient`, `token`) into a single Output with the summed `amount`.
-    /// @dev NOTE that here, Output.chainId denotes the *origin* chainId.
-    /// @param outputs - The Outputs to be transferred.
-    /// @custom:emits Filled
-    function fill(Output[] memory outputs) external payable {
-        // transfer outputs
-        _transferOutputs(outputs);
-
-        // emit
-        emit Filled(outputs);
-    }
-
-    /// @notice Fill any number of Order(s), by transferring their Output(s) via permit2 signed batch transfer.
-    /// @dev Can only provide ERC20 tokens as Outputs.
-    /// @dev Filler may aggregate multiple Outputs with the same (`chainId`, `recipient`, `token`) into a single Output with the summed `amount`.
-    /// @dev the permit2 signer is the Filler providing the Outputs.
-    /// @dev the permit2 `permitted` tokens MUST match provided Outputs.
-    /// @dev Filler MUST submit `fill` and `intitiate` within an atomic bundle.
-    /// @dev NOTE that here, Output.chainId denotes the *origin* chainId.
-    /// @param outputs - The Outputs to be transferred. signed over via permit2 witness.
-    /// @param permit2 - the permit2 details, signer, and signature.
-    /// @custom:emits Filled
-    function fillPermit2(Output[] memory outputs, OrdersPermit2.Permit2Batch calldata permit2) external {
-        // transfer all tokens to the Output recipients via permit2 (includes check on nonce & deadline)
-        _permitWitnessTransferFrom(
-            outputWitness(outputs), _fillTransferDetails(outputs, permit2.permit.permitted), permit2
-        );
-
-        // emit
-        emit Filled(outputs);
-    }
-
-    /// @notice Transfer the Order Outputs to their recipients.
-    function _transferOutputs(Output[] memory outputs) internal {
-        uint256 value = msg.value;
-        for (uint256 i; i < outputs.length; i++) {
-            if (outputs[i].token == address(0)) {
-                // this line should underflow if there's an attempt to spend more ETH than is attached to the transaction
-                value -= outputs[i].amount;
-                payable(outputs[i].recipient).transfer(outputs[i].amount);
-            } else {
-                IERC20(outputs[i].token).transferFrom(msg.sender, outputs[i].recipient, outputs[i].amount);
-            }
-        }
-    }
-}
-
 /// @notice Contract capable of registering initiation of intent-based Orders.
 abstract contract OrderOrigin is IOrders, OrdersPermit2 {
     /// @notice Thrown when an Order is submitted with a deadline that has passed.
@@ -154,11 +100,3 @@ abstract contract OrderOrigin is IOrders, OrdersPermit2 {
         }
     }
 }
-
-contract HostOrders is OrderDestination {
-    constructor(address _permit2) UsesPermit2(_permit2) {}
-}
-
-contract RollupOrders is OrderOrigin, OrderDestination {
-    constructor(address _permit2) UsesPermit2(_permit2) {}
-}

src/orders/Orders.sol

@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.24;
+
+import {OrderDestination} from "./OrderDestination.sol";
+import {OrderOrigin} from "./OrderOrigin.sol";
+import {UsesPermit2} from "../UsesPermit2.sol";
+
+contract HostOrders is OrderDestination {
+    constructor(address _permit2) UsesPermit2(_permit2) {}
+}
+
+contract RollupOrders is OrderOrigin, OrderDestination {
+    constructor(address _permit2) UsesPermit2(_permit2) {}
+}

src/permit2/UsesPermit2.sol → src/orders/OrdersPermit2.sol

@@ -1,41 +1,9 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.24;
 
+import {IOrders} from "./IOrders.sol";
+import {UsesPermit2} from "../UsesPermit2.sol";
 import {ISignatureTransfer} from "permit2/src/interfaces/ISignatureTransfer.sol";
-import {IOrders} from "../interfaces/IOrders.sol";
-
-abstract contract UsesPermit2 {
-    /// @param permit - the permit2 single token transfer details. includes a `deadline` and an unordered `nonce`.
-    /// @param signer - the signer of the permit2 info; the owner of the tokens.
-    /// @param signature - the signature over the permit + witness.
-    struct Permit2 {
-        ISignatureTransfer.PermitTransferFrom permit;
-        address owner;
-        bytes signature;
-    }
-
-    /// @param permit - the permit2 batch token transfer details. includes a `deadline` and an unordered `nonce`.
-    /// @param signer - the signer of the permit2 info; the owner of the tokens.
-    /// @param signature - the signature over the permit + witness.
-    struct Permit2Batch {
-        ISignatureTransfer.PermitBatchTransferFrom permit;
-        address owner;
-        bytes signature;
-    }
-
-    /// @notice Struct to hold the pre-hashed witness field and the witness type string.
-    struct Witness {
-        bytes32 witnessHash;
-        string witnessTypeString;
-    }
-
-    /// @notice The Permit2 contract address.
-    address immutable permit2Contract;
-
-    constructor(address _permit2) {
-        permit2Contract = _permit2;
-    }
-}
 
 abstract contract OrdersPermit2 is UsesPermit2 {
     string constant _OUTPUT_WITNESS_TYPESTRING =
@@ -128,72 +96,3 @@ abstract contract OrdersPermit2 is UsesPermit2 {
         }
     }
 }
-
-abstract contract PassagePermit2 is UsesPermit2 {
-    string constant _ENTER_WITNESS_TYPESTRING =
-        "EnterWitness witness)EnterWitness(uint256 rollupChainId,address rollupRecipient)TokenPermissions(address token,uint256 amount)";
-
-    bytes32 constant _ENTER_WITNESS_TYPEHASH = keccak256("EnterWitness(uint256 rollupChainId,address rollupRecipient)");
-
-    string constant _EXIT_WITNESS_TYPESTRING =
-        "ExitWitness witness)ExitWitness(address hostRecipient)TokenPermissions(address token,uint256 amount)";
-
-    bytes32 constant _EXIT_WITNESS_TYPEHASH = keccak256("ExitWitness(address hostRecipient)");
-
-    /// @notice Struct to hash Enter witness data into a 32-byte witness field, in an EIP-712 compliant way.
-    struct EnterWitness {
-        uint256 rollupChainId;
-        address rollupRecipient;
-    }
-
-    /// @notice Struct to hash Exit witness data into a 32-byte witness field, in an EIP-712 compliant way.
-    struct ExitWitness {
-        address hostRecipient;
-    }
-
-    /// @notice Encode & hash the rollupChainId and rollupRecipient for use as a permit2 witness.
-    /// @return _witness - the hashed witness and its typestring.
-    function enterWitness(uint256 rollupChainId, address rollupRecipient)
-        public
-        pure
-        returns (Witness memory _witness)
-    {
-        _witness.witnessHash =
-            keccak256(abi.encode(_ENTER_WITNESS_TYPEHASH, EnterWitness(rollupChainId, rollupRecipient)));
-        _witness.witnessTypeString = _ENTER_WITNESS_TYPESTRING;
-    }
-
-    /// @notice Hash the hostRecipient for use as a permit2 witness.
-    /// @return _witness - the hashed witness and its typestring.
-    function exitWitness(address hostRecipient) public pure returns (Witness memory _witness) {
-        _witness.witnessHash = keccak256(abi.encode(_EXIT_WITNESS_TYPEHASH, ExitWitness(hostRecipient)));
-        _witness.witnessTypeString = _EXIT_WITNESS_TYPESTRING;
-    }
-
-    /// @notice Transfer tokens using permit2.
-    /// @param _witness - the hashed witness and its typestring.
-    /// @param permit2 - the Permit2 information.
-    function _permitWitnessTransferFrom(Witness memory _witness, Permit2 calldata permit2) internal {
-        ISignatureTransfer(permit2Contract).permitWitnessTransferFrom(
-            permit2.permit,
-            _selfTransferDetails(permit2.permit.permitted.amount),
-            permit2.owner,
-            _witness.witnessHash,
-            _witness.witnessTypeString,
-            permit2.signature
-        );
-    }
-
-    /// @notice Construct TransferDetails transferring a balance to this contract, for passing to permit2.
-    /// @dev always transfers the full amount to address(this).
-    /// @param amount - the amount to transfer to this contract.
-    /// @return transferDetails - the SignatureTransferDetails generated.
-    function _selfTransferDetails(uint256 amount)
-        internal
-        view
-        returns (ISignatureTransfer.SignatureTransferDetails memory transferDetails)
-    {
-        transferDetails.to = address(this);
-        transferDetails.requestedAmount = amount;
-    }
-}