feat: Sketch for OneTransferFromOnly.sol

Took 49 seconds

foundry/src/OneTransferFromOnly.sol

@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: BUSL-1.1
+pragma solidity ^0.8.26;
+
+import "@interfaces/IExecutor.sol";
+import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
+import "@permit2/src/interfaces/IAllowanceTransfer.sol";
+
+error TokenTransfer__AddressZero();
+
+contract OneTransferFromOnly {
+    using SafeERC20 for IERC20;
+
+    // this is a stupid name but the compiler was complaining that we already had a permit2 variable in TychoRouter
+    IAllowanceTransfer public immutable permit2lal;
+    uint256 private constant _TOKEN_IN_SLOT = 123;
+    uint256 private constant _AMOUNT_IN_SLOT = 124;
+    uint256 private constant _IS_PERMIT2_SLOT = 125;
+    uint256 private constant _SENDER_SLOT = 126;
+    uint256 private constant _IS_TRANSFER_EXECUTED_SLOT = 127;
+
+    constructor(address _permit2) {
+        if (_permit2 == address(0)) {
+            revert TokenTransfer__AddressZero();
+        }
+        permit2lal = IAllowanceTransfer(_permit2);
+    }
+
+    function tstoreTransferFromInfo(
+        address tokenIn,
+        address amountIn,
+        bool isPermit2,
+        address sender
+    ) internal {
+        assembly {
+            tstore(_TOKEN_IN_SLOT, tokenIn)
+            tstore(_AMOUNT_IN_SLOT, amountIn)
+            tstore(_IS_PERMIT2_SLOT, isPermit2)
+            tstore(_SENDER_SLOT, sender)
+            tstore(_IS_TRANSFER_EXECUTED_SLOT, false)
+        }
+    }
+
+    function _transfer(address receiver)
+        // we could pass the amount and address too and compare to what is in the slots?
+        internal
+    {
+        address tokenIn;
+        uint256 amount;
+        bool isPermit2;
+        address sender;
+        bool isTransferExecuted;
+        assembly {
+            tokenIn := tload(_TOKEN_IN_SLOT)
+            amount := tload(_AMOUNT_IN_SLOT)
+            isPermit2 := tload(_IS_PERMIT2_SLOT)
+            sender := tload(_SENDER_SLOT)
+            isTransferExecuted := tload(_IS_TRANSFER_EXECUTED_SLOT)
+        }
+        if (isTransferExecuted) {
+            return; // or revert?
+        }
+
+        if (isPermit2) {
+            // Permit2.permit is already called from the TychoRouter
+            permit2lal.transferFrom(sender, receiver, uint160(amount), tokenIn);
+            assembly {
+                tstore(_IS_TRANSFER_EXECUTED_SLOT, true)
+            }
+        } else {
+            // slither-disable-next-line arbitrary-send-erc20
+            IERC20(tokenIn).safeTransferFrom(sender, receiver, amount);
+            assembly {
+                tstore(_IS_TRANSFER_EXECUTED_SLOT, true)
+            }
+        }
+    }
+}