feat: perform all transfers in executors

For organization (and thus safety) purposes.

Rename to RestrictTransferFrom.sol so that we can perform multiple transfer froms (upto an allowance) in the case of split swaps (where the split is the first swap).

TODO: Fix tests.

foundry/src/executors/UniswapV4Executor.sol

@@ -22,7 +22,7 @@ import {IUnlockCallback} from
 import {SafeCast} from "@uniswap/v4-core/src/libraries/SafeCast.sol";
 import {TransientStateLibrary} from
     "@uniswap/v4-core/src/libraries/TransientStateLibrary.sol";
-import "../OneTransferFromOnly.sol";
+import "../RestrictTransferFrom.sol";
 import "@openzeppelin/contracts/utils/Address.sol";
 
 error UniswapV4Executor__InvalidDataLength();
@@ -38,7 +38,7 @@ contract UniswapV4Executor is
     IExecutor,
     IUnlockCallback,
     ICallback,
-    OneTransferFromOnly
+RestrictTransferFrom
 {
     using SafeERC20 for IERC20;
     using CurrencyLibrary for Currency;
@@ -58,7 +58,7 @@ contract UniswapV4Executor is
     }
 
     constructor(IPoolManager _poolManager, address _permit2)
-        OneTransferFromOnly(_permit2)
+        RestrictTransferFrom(_permit2)
     {
         poolManager = _poolManager;
         _self = address(this);
@@ -83,8 +83,7 @@ contract UniswapV4Executor is
             address tokenIn,
             address tokenOut,
             bool zeroForOne,
-            bool transferFromNeeded,
-            bool transferNeeded,
+            TransferType transferType,
             address receiver,
             UniswapV4Executor.UniswapV4Pool[] memory pools
         ) = _decodeData(data);
@@ -102,8 +101,7 @@ contract UniswapV4Executor is
                 key,
                 zeroForOne,
                 amountIn,
-                transferFromNeeded,
-                transferNeeded,
+                transferType,
                 receiver,
                 bytes("")
             );
@@ -125,8 +123,7 @@ contract UniswapV4Executor is
                 currencyIn,
                 path,
                 amountIn,
-                transferFromNeeded,
-                transferNeeded,
+                transferType,
                 receiver
             );
         }
@@ -144,26 +141,24 @@ contract UniswapV4Executor is
             address tokenIn,
             address tokenOut,
             bool zeroForOne,
-            bool transferFromNeeded,
-            bool transferNeeded,
+            TransferType transferType,
             address receiver,
             UniswapV4Pool[] memory pools
         )
     {
-        if (data.length < 89) {
+        if (data.length < 88) {
             revert UniswapV4Executor__InvalidDataLength();
         }
 
         tokenIn = address(bytes20(data[0:20]));
         tokenOut = address(bytes20(data[20:40]));
         zeroForOne = data[40] != 0;
-        transferFromNeeded = data[41] != 0;
-        transferNeeded = data[42] != 0;
-        receiver = address(bytes20(data[43:63]));
+        transferType = TransferType(uint8(data[41]));
+        receiver = address(bytes20(data[42:62]));
 
-        uint256 poolsLength = (data.length - 63) / 26; // 26 bytes per pool object
+        uint256 poolsLength = (data.length - 62) / 26; // 26 bytes per pool object
         pools = new UniswapV4Pool[](poolsLength);
-        bytes memory poolsData = data[63:];
+        bytes memory poolsData = data[62:];
         uint256 offset = 0;
         for (uint256 i = 0; i < poolsLength; i++) {
             address intermediaryToken;
@@ -243,8 +238,7 @@ contract UniswapV4Executor is
      * @param poolKey The key of the pool to swap in.
      * @param zeroForOne Whether the swap is from token0 to token1 (true) or vice versa (false).
      * @param amountIn The amount of tokens to swap in.
-     * @param transferFromNeeded Whether to transferFrom input tokens into the core contract from the swapper's wallet .
-     * @param transferNeeded Whether to transfer input tokens into the core contract from the router contract
+     * @param transferType The type of action necessary to pay back the pool.
      * @param receiver The address of the receiver.
      * @param hookData Additional data for hook contracts.
      */
@@ -252,8 +246,7 @@ contract UniswapV4Executor is
         PoolKey memory poolKey,
         bool zeroForOne,
         uint128 amountIn,
-        bool transferFromNeeded,
-        bool transferNeeded,
+        TransferType transferType,
         address receiver,
         bytes calldata hookData
     ) external returns (uint128) {
@@ -266,7 +259,7 @@ contract UniswapV4Executor is
         if (amount > amountIn) {
             revert UniswapV4Executor__V4TooMuchRequested(amountIn, amount);
         }
-        _settle(currencyIn, amount, transferFromNeeded, transferNeeded);
+        _settle(currencyIn, amount, transferType);
 
         Currency currencyOut =
             zeroForOne ? poolKey.currency1 : poolKey.currency0;
@@ -279,16 +272,14 @@ contract UniswapV4Executor is
      * @param currencyIn The currency of the input token.
      * @param path The path to swap along.
      * @param amountIn The amount of tokens to swap in.
-     * @param transferFromNeeded Whether to transferFrom input tokens into the core contract from the swapper's wallet .
-     * @param transferNeeded Whether to transfer input tokens into the core contract from the router contract
+     * @param transferType The type of action necessary to pay back the pool.
      * @param receiver The address of the receiver.
      */
     function swapExactInput(
         Currency currencyIn,
         PathKey[] calldata path,
         uint128 amountIn,
-        bool transferFromNeeded,
-        bool transferNeeded,
+        TransferType transferType,
         address receiver
     ) external returns (uint128) {
         uint128 amountOut = 0;
@@ -319,7 +310,7 @@ contract UniswapV4Executor is
         if (amount > amountIn) {
             revert UniswapV4Executor__V4TooMuchRequested(amountIn, amount);
         }
-        _settle(currencyIn, amount, transferFromNeeded, transferNeeded);
+        _settle(currencyIn, amount, transferType);
 
         _take(
             swapCurrencyIn, // at the end of the loop this is actually currency out
@@ -391,17 +382,13 @@ contract UniswapV4Executor is
      * @dev The implementing contract must ensure that the `payer` is a secure address.
      * @param currency The currency to settle.
      * @param amount The amount to send.
-     * @param transferFromNeeded Whether to manually transferFrom input tokens into the
-     *  core contract from the swapper.
-     * @param transferNeeded Whether to manually transfer input tokens into the
-     *  core contract from the router.
+     * @param transferType The type of action necessary to pay back the pool.
      * @dev Returns early if the amount is 0.
      */
     function _settle(
         Currency currency,
         uint256 amount,
-        bool transferFromNeeded,
-        bool transferNeeded
+        TransferType transferType
     ) internal {
         if (amount == 0) return;
         poolManager.sync(currency);
@@ -409,18 +396,12 @@ contract UniswapV4Executor is
             // slither-disable-next-line unused-return
             poolManager.settle{value: amount}();
         } else {
-            if (transferFromNeeded) {
-                // transferFrom swapper's wallet into the core contract
-                _transfer(address(poolManager));
-            } else if (transferNeeded) {
-                address tokenIn = Currency.unwrap(currency);
-                // transfer from router contract into the core contract
-                if (tokenIn == address(0)) {
-                    Address.sendValue(payable(address(poolManager)), amount);
-                } else {
-                    IERC20(tokenIn).safeTransfer(address(poolManager), amount);
-                }
-            }
+            _transfer(
+                address(poolManager),
+                transferType,
+                address(currency),
+                amount
+            );
             // slither-disable-next-line unused-return
             poolManager.settle();
         }