harb/onchain/test/helpers/LiquidityBoundaryHelper.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.19;

import {IUniswapV3Pool} from "@uniswap/v3-core/contracts/interfaces/IUniswapV3Pool.sol";
import {TickMath} from "@aperture/uni-v3-lib/TickMath.sol";
import {LiquidityAmounts} from "@aperture/uni-v3-lib/LiquidityAmounts.sol";
import {ThreePositionStrategy} from "../../src/abstracts/ThreePositionStrategy.sol";

/**
 * @title LiquidityBoundaryHelper
 * @notice Helper library for calculating safe trade sizes within liquidity boundaries
 * @dev Prevents trades that would exceed available liquidity and cause SPL errors
 */
library LiquidityBoundaryHelper {
    /**
     * @notice Calculates the maximum ETH amount that can be traded (buy HARB) without exceeding position liquidity limits
     * @param pool The Uniswap V3 pool
     * @param liquidityManager The liquidity manager contract
     * @param token0isWeth Whether token0 is WETH
     * @return maxEthAmount Maximum ETH that can be safely traded
     */
    function calculateBuyLimit(
        IUniswapV3Pool pool,
        ThreePositionStrategy liquidityManager,
        bool token0isWeth
    ) internal view returns (uint256 maxEthAmount) {
        (, int24 currentTick,,,,,) = pool.slot0();
        
        // Get position data
        (uint128 anchorLiquidity, int24 anchorLower, int24 anchorUpper) = liquidityManager.positions(ThreePositionStrategy.Stage.ANCHOR);
        (uint128 discoveryLiquidity, int24 discoveryLower, int24 discoveryUpper) = liquidityManager.positions(ThreePositionStrategy.Stage.DISCOVERY);
        
        // If no positions exist, return 0 (no safe limit)
        if (anchorLiquidity == 0 && discoveryLiquidity == 0) {
            return 0;
        }
        
        uint256 maxEth = 0;
        
        // Check anchor position
        if (currentTick >= anchorLower && currentTick < anchorUpper && anchorLiquidity > 0) {
            uint160 currentSqrtPrice = TickMath.getSqrtRatioAtTick(currentTick);
            uint160 upperSqrtPrice = TickMath.getSqrtRatioAtTick(anchorUpper);
            
            if (token0isWeth) {
                maxEth = LiquidityAmounts.getAmount0ForLiquidity(currentSqrtPrice, upperSqrtPrice, anchorLiquidity);
            } else {
                maxEth = LiquidityAmounts.getAmount1ForLiquidity(currentSqrtPrice, upperSqrtPrice, anchorLiquidity);
            }
        }
        // Check discovery position
        else if (currentTick >= discoveryLower && currentTick < discoveryUpper && discoveryLiquidity > 0) {
            uint160 currentSqrtPrice = TickMath.getSqrtRatioAtTick(currentTick);
            uint160 upperSqrtPrice = TickMath.getSqrtRatioAtTick(discoveryUpper);
            
            if (token0isWeth) {
                maxEth = LiquidityAmounts.getAmount0ForLiquidity(currentSqrtPrice, upperSqrtPrice, discoveryLiquidity);
            } else {
                maxEth = LiquidityAmounts.getAmount1ForLiquidity(currentSqrtPrice, upperSqrtPrice, discoveryLiquidity);
            }
        }
        
        // Apply safety margin (90% of calculated max)
        return (maxEth * 9) / 10;
    }
    
    /**
     * @notice Calculates the maximum HARB amount that can be traded (sell HARB) without exceeding position liquidity limits
     * @param pool The Uniswap V3 pool
     * @param liquidityManager The liquidity manager contract
     * @param token0isWeth Whether token0 is WETH
     * @return maxHarbAmount Maximum HARB that can be safely traded
     */
    function calculateSellLimit(
        IUniswapV3Pool pool,
        ThreePositionStrategy liquidityManager,
        bool token0isWeth
    ) internal view returns (uint256 maxHarbAmount) {
        (, int24 currentTick,,,,,) = pool.slot0();
        
        // Get position data
        (uint128 anchorLiquidity, int24 anchorLower, int24 anchorUpper) = liquidityManager.positions(ThreePositionStrategy.Stage.ANCHOR);
        (uint128 floorLiquidity, int24 floorLower, int24 floorUpper) = liquidityManager.positions(ThreePositionStrategy.Stage.FLOOR);
        
        // If no positions exist, return 0 (no safe limit)
        if (anchorLiquidity == 0 && floorLiquidity == 0) {
            return 0;
        }
        
        uint256 maxHarb = 0;
        
        // Check anchor position
        if (currentTick >= anchorLower && currentTick < anchorUpper && anchorLiquidity > 0) {
            uint160 currentSqrtPrice = TickMath.getSqrtRatioAtTick(currentTick);
            uint160 lowerSqrtPrice = TickMath.getSqrtRatioAtTick(anchorLower);
            
            if (token0isWeth) {
                maxHarb = LiquidityAmounts.getAmount1ForLiquidity(lowerSqrtPrice, currentSqrtPrice, anchorLiquidity);
            } else {
                maxHarb = LiquidityAmounts.getAmount0ForLiquidity(lowerSqrtPrice, currentSqrtPrice, anchorLiquidity);
            }
        }
        // Check floor position
        else if (currentTick >= floorLower && currentTick < floorUpper && floorLiquidity > 0) {
            uint160 currentSqrtPrice = TickMath.getSqrtRatioAtTick(currentTick);
            uint160 lowerSqrtPrice = TickMath.getSqrtRatioAtTick(floorLower);
            
            if (token0isWeth) {
                maxHarb = LiquidityAmounts.getAmount1ForLiquidity(lowerSqrtPrice, currentSqrtPrice, floorLiquidity);
            } else {
                maxHarb = LiquidityAmounts.getAmount0ForLiquidity(lowerSqrtPrice, currentSqrtPrice, floorLiquidity);
            }
        }
        
        // Apply safety margin (90% of calculated max)
        return (maxHarb * 9) / 10;
    }
}