feat: Add dynamic fee first version

prb-math: https://github.com/PaulRBerg/prb-math

src/pool-cl/dynamic-fee/CLDynamicFeeHook.sol

@@ -0,0 +1,204 @@
+// SPDX-License-Identifier: BUSL-1.1
+pragma solidity ^0.8.19;
+
+import {CLBaseHook} from "../CLBaseHook.sol";
+import {FullMath} from "pancake-v4-core/src/pool-cl/libraries/FullMath.sol";
+import {FixedPoint96} from "pancake-v4-core/src/pool-cl/libraries/FixedPoint96.sol";
+import {LPFeeLibrary} from "pancake-v4-core/src/libraries/LPFeeLibrary.sol";
+import {PoolKey} from "pancake-v4-core/src/types/PoolKey.sol";
+import {PoolId, PoolIdLibrary} from "pancake-v4-core/src/types/PoolId.sol";
+import {Currency} from "pancake-v4-core/src/types/Currency.sol";
+import {BeforeSwapDelta, BeforeSwapDeltaLibrary} from "pancake-v4-core/src/types/BeforeSwapDelta.sol";
+import {
+    HOOKS_BEFORE_INITIALIZE_OFFSET,
+    HOOKS_BEFORE_SWAP_OFFSET
+} from "pancake-v4-core/src/pool-cl/interfaces/ICLHooks.sol";
+import {ICLPoolManager} from "pancake-v4-core/src/pool-cl/interfaces/ICLPoolManager.sol";
+import {CLPoolManager} from "pancake-v4-core/src/pool-cl/CLPoolManager.sol";
+import {SD59x18, UNIT, convert, sub, mul, div, inv, exp, lt} from "prb-math/SD59x18.sol";
+
+import {IPriceFeed} from "./interfaces/IPriceFeed.sol";
+
+contract CLDynamicFeeHook is CLBaseHook {
+    using PoolIdLibrary for PoolKey;
+    using LPFeeLibrary for uint24;
+
+    struct PoolInfo {
+        IPriceFeed priceFeed;
+        uint24 DFF_max; // in hundredth of bips
+    }
+
+    struct InitializeHookData {
+        IPriceFeed priceFeed;
+        uint24 DFF_max;
+    }
+
+    struct CallbackData {
+        address sender;
+        PoolKey key;
+        ICLPoolManager.SwapParams params;
+        bytes hookData;
+    }
+
+    mapping(PoolId id => PoolInfo poolInfo) public poolInfos;
+
+    uint24 private _fee;
+    bool private _isSim;
+
+    error NotDynamicFeePool();
+    error PriceFeedTokensNotMatch();
+    error DFFMaxTooLarge();
+    error DFFTooLarge();
+    error SwapAndRevert(uint160 sqrtPriceX96);
+
+    constructor(ICLPoolManager poolManager) CLBaseHook(poolManager) {}
+
+    function getHooksRegistrationBitmap() external view override returns (uint16) {
+        return uint16(1 << HOOKS_BEFORE_INITIALIZE_OFFSET | 1 << HOOKS_BEFORE_SWAP_OFFSET);
+    }
+
+    function beforeInitialize(address sender, PoolKey calldata key, uint160 sqrtPriceX96, bytes calldata hookData)
+        external
+        override
+        poolManagerOnly
+        returns (bytes4)
+    {
+        if (!key.fee.isDynamicLPFee()) {
+            revert NotDynamicFeePool();
+        }
+
+        InitializeHookData memory initializeHookData = abi.decode(hookData, (InitializeHookData));
+
+        IPriceFeed priceFeed = IPriceFeed(initializeHookData.priceFeed);
+        if (
+            address(priceFeed.token0()) != Currency.unwrap(key.currency0)
+                || address(priceFeed.token1()) != Currency.unwrap(key.currency1)
+        ) {
+            revert PriceFeedTokensNotMatch();
+        }
+
+        if (initializeHookData.DFF_max > 1000000) {
+            revert DFFMaxTooLarge();
+        }
+
+        poolInfos[key.toId()] = PoolInfo({priceFeed: priceFeed, DFF_max: initializeHookData.DFF_max});
+
+        return this.beforeInitialize.selector;
+    }
+
+    function beforeSwap(
+        address sender,
+        PoolKey calldata key,
+        ICLPoolManager.SwapParams calldata params,
+        bytes calldata hookData
+    ) external override returns (bytes4, BeforeSwapDelta, uint24) {
+        uint24 staticFee = key.fee & (~LPFeeLibrary.DYNAMIC_FEE_FLAG);
+
+        if (_isSim) {
+            _fee = staticFee;
+            poolManager.updateDynamicLPFee(key, _fee);
+
+            return (this.beforeSwap.selector, BeforeSwapDeltaLibrary.ZERO_DELTA, 0);
+        }
+
+        PoolId id = key.toId();
+
+        (uint160 sqrtPriceX96Before,,,) = poolManager.getSlot0(id);
+        uint160 sqrtPriceX96After = _simulateSwap(key, params, hookData);
+
+        uint160 priceX96Before = uint160(FullMath.mulDiv(sqrtPriceX96Before, sqrtPriceX96Before, FixedPoint96.Q96));
+        uint160 priceX96After = uint160(FullMath.mulDiv(sqrtPriceX96After, sqrtPriceX96After, FixedPoint96.Q96));
+
+        PoolInfo memory poolInfo = poolInfos[id];
+        uint256 priceX96Oracle = poolInfo.priceFeed.getPriceX96();
+
+        uint256 sfX96;
+        {
+            if (priceX96After > priceX96Before && priceX96Oracle > priceX96Before) {
+                sfX96 =
+                    FullMath.mulDiv(priceX96After - priceX96Before, FixedPoint96.Q96, priceX96Oracle - priceX96Before);
+            }
+            if (priceX96After < priceX96Before && priceX96Oracle < priceX96Before) {
+                sfX96 =
+                    FullMath.mulDiv(priceX96Before - priceX96After, FixedPoint96.Q96, priceX96Before - priceX96Oracle);
+            }
+        }
+
+        uint256 ipX96;
+        {
+            uint256 r = FullMath.mulDiv(priceX96Before, FixedPoint96.Q96, priceX96Oracle);
+            ipX96 = r > FixedPoint96.Q96 ? r - FixedPoint96.Q96 : FixedPoint96.Q96 - r;
+        }
+
+        uint256 pifX96 = FullMath.mulDiv(sfX96, ipX96, FixedPoint96.Q96);
+
+        SD59x18 DFF;
+        uint256 fX96 = FullMath.mulDiv(key.fee.getInitialLPFee(), FixedPoint96.Q96, 1_000_000);
+        if (pifX96 > fX96) {
+            SD59x18 inter = inv(
+                exp(
+                    convert(int256(FullMath.mulDiv(pifX96 - fX96, FixedPoint96.Q96, fX96)))
+                        / convert(int256(FixedPoint96.Q96))
+                )
+            );
+            if (inter < UNIT) {
+                DFF = convert(int256(int24(poolInfo.DFF_max))) * (UNIT - inter);
+            }
+        }
+
+        if (DFF.isZero()) {
+            _fee = staticFee;
+            poolManager.updateDynamicLPFee(key, _fee);
+
+            return (this.beforeSwap.selector, BeforeSwapDeltaLibrary.ZERO_DELTA, 0);
+        }
+
+        if (DFF > convert(1_000_000)) {
+            revert DFFTooLarge();
+        }
+
+        _fee = uint24(int24(convert(DFF)));
+        poolManager.updateDynamicLPFee(key, _fee);
+
+        return (this.beforeSwap.selector, BeforeSwapDeltaLibrary.ZERO_DELTA, 0);
+    }
+
+    /// @dev Simulate `swap`
+    function _simulateSwap(PoolKey calldata key, ICLPoolManager.SwapParams calldata params, bytes calldata hookData)
+        internal
+        returns (uint160 sqrtPriceX96)
+    {
+        _isSim = true;
+        // TODO: Ugly, should add vault() to IFees interface!
+        try CLPoolManager(address(poolManager)).vault().lock(
+            abi.encode(CallbackData({sender: msg.sender, key: key, params: params, hookData: hookData}))
+        ) {
+            revert();
+        } catch (bytes memory reason) {
+            bytes4 selector;
+            assembly {
+                selector := mload(add(reason, 0x20))
+            }
+            if (selector != SwapAndRevert.selector) {
+                revert();
+            }
+            // Extract data by trimming the custom error selector (first 4 bytes)
+            bytes memory data = new bytes(reason.length - 4);
+            for (uint256 i = 4; i < reason.length; ++i) {
+                data[i - 4] = reason[i];
+            }
+            sqrtPriceX96 = abi.decode(data, (uint160));
+        }
+        _isSim = false;
+    }
+
+    /// @dev Revert a custom error on purpose to achieve simulation of `swap`
+    function lockAcquired(bytes calldata rawData) external override returns (bytes memory) {
+        CallbackData memory data = abi.decode(rawData, (CallbackData));
+
+        poolManager.swap(data.key, data.params, data.hookData);
+
+        (uint160 sqrtPriceX96,,,) = poolManager.getSlot0(data.key.toId());
+        revert SwapAndRevert(sqrtPriceX96);
+    }
+}

src/pool-cl/dynamic-fee/PriceFeed.sol

@@ -0,0 +1,36 @@
+// SPDX-License-Identifier: BUSL-1.1
+pragma solidity ^0.8.19;
+
+import {IERC20Metadata} from "openzeppelin-contracts/contracts/token/ERC20/extensions/IERC20Metadata.sol";
+import {AggregatorV3Interface} from "./interfaces/AggregatorV3Interface.sol";
+import {FullMath} from "pancake-v4-core/src/pool-cl/libraries/FullMath.sol";
+import {FixedPoint96} from "pancake-v4-core/src/pool-cl/libraries/FixedPoint96.sol";
+
+import {IPriceFeed} from "./interfaces/IPriceFeed.sol";
+
+contract PriceFeed is IPriceFeed {
+    IERC20Metadata public immutable token0;
+    IERC20Metadata public immutable token1;
+
+    AggregatorV3Interface public immutable oracle;
+
+    constructor(address token0_, address token1_, address oracle_) {
+        if (token0_ > token1_) {
+            (token0_, token1_) = (token1_, token0_);
+        }
+        token0 = IERC20Metadata(token0_);
+        token1 = IERC20Metadata(token1_);
+        oracle = AggregatorV3Interface(oracle_);
+    }
+
+    /// @dev Override if the oracle base quote tokens do not match the order of
+    /// token0 and token1, i.e., the price from oracle needs to be inversed, or
+    /// if there is no corresponding oracle for token0 token1 pair so that
+    /// combination of two oracles is required
+    function getPriceX96() external view virtual returns (uint160 priceX96) {
+        (, int256 answer,,,) = oracle.latestRoundData();
+        priceX96 = uint160(FullMath.mulDiv(uint256(answer), FixedPoint96.Q96, 10 ** oracle.decimals()));
+        priceX96 = uint160(FullMath.mulDiv(priceX96, token1.decimals(), token0.decimals()));
+        // TODO: Is it better to cache the result?
+    }
+}

src/pool-cl/dynamic-fee/interfaces/AggregatorV3Interface.sol

@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+/// @dev Copy from @chainlink/contracts(1.2.0)
+interface AggregatorV3Interface {
+    function decimals() external view returns (uint8);
+
+    function description() external view returns (string memory);
+
+    function version() external view returns (uint256);
+
+    function getRoundData(uint80 _roundId)
+        external
+        view
+        returns (uint80 roundId, int256 answer, uint256 startedAt, uint256 updatedAt, uint80 answeredInRound);
+
+    function latestRoundData()
+        external
+        view
+        returns (uint80 roundId, int256 answer, uint256 startedAt, uint256 updatedAt, uint80 answeredInRound);
+}

src/pool-cl/dynamic-fee/interfaces/IPriceFeed.sol

@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: BUSL-1.1
+pragma solidity ^0.8.19;
+
+import {IERC20Metadata} from "openzeppelin-contracts/contracts/token/ERC20/extensions/IERC20Metadata.sol";
+
+interface IPriceFeed {
+    function token0() external view returns (IERC20Metadata);
+
+    function token1() external view returns (IERC20Metadata);
+
+    function getPriceX96() external view returns (uint160 priceX96);
+}