5.6: Added variable minAmount to nftclaim in order to facilitate exte…

…rnal price checking for slippage comparisson
alchemix-finance · Feb 4, 2024 · 9214afd · 9214afd
1 parent baec95a
commit 9214afd
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Showing 3 changed files with 51 additions and 35 deletions.
diff --git a/src/FluxToken.sol b/src/FluxToken.sol
@@ -1,8 +1,6 @@
 // SPDX-License-Identifier: GPL-3
 pragma solidity ^0.8.15;
 
-import "lib/forge-std/src/console2.sol";
-
 import "src/interfaces/IFluxToken.sol";
 import "src/interfaces/IVotingEscrow.sol";
 import "src/interfaces/IAlchemechNFT.sol";
@@ -112,35 +110,22 @@ contract FluxToken is ERC20("Flux", "FLUX"), IFluxToken {
     }
 
     /// @inheritdoc IFluxToken
-    function nftClaim(address _nft, uint256 _tokenId) external {
+    function nftClaim(address _nft, uint256 _tokenId, uint256 _minAmount) external {
         // require claim to be within a year of deploy date
         require(block.timestamp < deployDate + oneYear, "claim period has passed");
 
         require(!claimed[_nft][_tokenId], "already claimed");
 
         // value of the NFT
-        uint256 tokenData = 0;
-
-        // determine which nft is being claimed
-        if (_nft == alchemechNFT) {
-            // require sender to be owner of the NFT
-            require(IAlchemechNFT(_nft).ownerOf(_tokenId) == msg.sender, "not owner of Alchemech NFT");
-
-            tokenData = IAlchemechNFT(_nft).tokenData(_tokenId);
-        } else if (_nft == patronNFT) {
-            // require sender to be owner of the NFT
-            require(IAlEthNFT(_nft).ownerOf(_tokenId) == msg.sender, "not owner of Patron NFT");
-
-            tokenData = IAlEthNFT(_nft).tokenData(_tokenId);
-        } else {
-            revert("invalid NFT");
-        }
+        uint256 tokenData = getNFTValue(_nft, _tokenId);
 
         // mark the token as claimed
         claimed[_nft][_tokenId] = true;
 
         uint256 amount = getClaimableFlux(tokenData, _nft);
 
+        require(amount >= _minAmount, "Slippage Exceeded");
+
         _mint(msg.sender, amount);
     }
 
@@ -196,21 +181,47 @@ contract FluxToken is ERC20("Flux", "FLUX"), IFluxToken {
     function getClaimableFlux(uint256 _amount, address _nft) public view returns (uint256 claimableFlux) {
         uint256 bpt = _calculateBPT(_amount);
 
-        uint256 veMul = IVotingEscrow(veALCX).MULTIPLIER();
-        uint256 veMax = IVotingEscrow(veALCX).MAXTIME();
-        uint256 fluxPerVe = IVotingEscrow(veALCX).fluxPerVeALCX();
-        uint256 fluxMul = IVotingEscrow(veALCX).fluxMultiplier();
+        uint256 slope = (bpt * IVotingEscrow(veALCX).MULTIPLIER()) / IVotingEscrow(veALCX).MAXTIME();
+
+        // Calculate as if time is maxtime
+        uint256 bias = (slope * ((block.timestamp + IVotingEscrow(veALCX).MAXTIME()) - block.timestamp));
+
+        // Total amount of flux that would be earned from the amount
+        uint256 totalFlux = (bias * (IVotingEscrow(veALCX).fluxPerVeALCX() + BPS)) / BPS;
 
-        // Amount of flux earned in 1 yr from _amount assuming it was deposited for maxtime
-        claimableFlux = (((bpt * veMul) / veMax) * veMax * (fluxPerVe + BPS)) / BPS / fluxMul;
+        // Amount of flux that would be claimable
+        claimableFlux = totalFlux / IVotingEscrow(veALCX).fluxMultiplier();
 
         // Claimable flux for alchemechNFT is different than patronNFT
         if (_nft == alchemechNFT) {
             claimableFlux = (claimableFlux * alchemechMultiplier) / BPS;
         }
     }
 
-    function _calculateBPT(uint256 _amount) public view returns (uint256 bptOut) {
+    // Retrieves tokenData from the specified nft
+    function getNFTValue(address _nft, uint256 _tokenId) public view returns (uint256) {
+        // value of the NFT
+        uint256 tokenData = 0;
+
+        // determine which nft is being claimed
+        if (_nft == alchemechNFT) {
+            // require sender to be owner of the NFT
+            require(IAlchemechNFT(_nft).ownerOf(_tokenId) == msg.sender, "not owner of Alchemech NFT");
+
+            tokenData = IAlchemechNFT(_nft).tokenData(_tokenId);
+        } else if (_nft == patronNFT) {
+            // require sender to be owner of the NFT
+            require(IAlEthNFT(_nft).ownerOf(_tokenId) == msg.sender, "not owner of Patron NFT");
+
+            tokenData = IAlEthNFT(_nft).tokenData(_tokenId);
+        } else {
+            revert("invalid NFT");
+        }
+
+        return tokenData;
+    }
+
+    function _calculateBPT(uint256 _amount) internal view returns (uint256 bptOut) {
         address distributor = IVotingEscrow(veALCX).distributor();
 
         (bytes32 balancerPoolId, address balancerPool, address balancerVault) = IRewardsDistributor(distributor)

diff --git a/src/interfaces/IFluxToken.sol b/src/interfaces/IFluxToken.sol
@@ -52,10 +52,11 @@ interface IFluxToken is IERC20 {
      * @notice Mints tokens to a recipient.
      * @param _nft NFT contract address to claim from.
      * @param _tokenId NFT tokenId to claim from.
+     * @param _minAmount Minimum tokens to accept from the claim.
      * @dev This will revert after set claim period, if the NFT has already been claimed, or if the caller is not the owner of the NFT
      * @dev Amount of FLUX minted is one year of potential FLUX rewards given the NFTs value.
      */
-    function nftClaim(address _nft, uint256 _tokenId) external;
+    function nftClaim(address _nft, uint256 _tokenId, uint256 _minAmount) external;
 
     /**
      * @dev Burns `amount` tokens from `account`, deducting from the caller's allowance.

diff --git a/src/test/FluxToken.t.sol b/src/test/FluxToken.t.sol
@@ -25,12 +25,16 @@ contract FluxTokenTest is BaseTest {
         uint256 alchemechTotalNoMultiplier = flux.getClaimableFlux(tokenData2, patronNFT);
 
         assertGt(alchemechTotalNoMultiplier, alchemechTotal, "non multiplier calc should be higher");
+
+        uint256 expectedAmount = flux.getClaimableFlux(flux.getNFTValue(patronNFT, tokenId), patronNFT);
 
         hevm.prank(ownerOfPatronNFT);
-        flux.nftClaim(patronNFT, tokenId);
+        flux.nftClaim(patronNFT, tokenId, expectedAmount * 9_900 / 10_000);
+
+        expectedAmount = flux.getClaimableFlux(flux.getNFTValue(alchemechNFT, tokenId), alchemechNFT);
 
         hevm.prank(ownerOfAlchemechNFT);
-        flux.nftClaim(alchemechNFT, tokenId);
+        flux.nftClaim(alchemechNFT, tokenId, expectedAmount * 9_900 / 10_000);
 
         assertEq(flux.balanceOf(ownerOfPatronNFT), patronTotal, "owner should have patron flux");
         assertEq(flux.balanceOf(ownerOfAlchemechNFT), alchemechTotal, "owner should have alchemech flux");
@@ -43,28 +47,28 @@ contract FluxTokenTest is BaseTest {
 
         hevm.expectRevert(abi.encodePacked("invalid NFT"));
         hevm.prank(ownerOfPatronNFT);
-        flux.nftClaim(address(0), tokenId);
+        flux.nftClaim(address(0), tokenId, 0);
 
         hevm.expectRevert(abi.encodePacked("not owner of Patron NFT"));
         hevm.prank(ownerOfAlchemechNFT);
-        flux.nftClaim(patronNFT, tokenId);
+        flux.nftClaim(patronNFT, tokenId, 0);
 
         hevm.expectRevert(abi.encodePacked("not owner of Alchemech NFT"));
         hevm.prank(ownerOfPatronNFT);
-        flux.nftClaim(alchemechNFT, tokenId);
+        flux.nftClaim(alchemechNFT, tokenId, 0);
 
         // Attempt to claim twice
         hevm.startPrank(ownerOfPatronNFT);
-        flux.nftClaim(patronNFT, tokenId);
+        flux.nftClaim(patronNFT, tokenId, 0);
 
         hevm.expectRevert(abi.encodePacked("already claimed"));
-        flux.nftClaim(patronNFT, tokenId);
+        flux.nftClaim(patronNFT, tokenId, 0);
         hevm.stopPrank();
 
         // Attempt to claim after claim period (1 year)
         hevm.warp(block.timestamp + 366 days);
         hevm.expectRevert(abi.encodePacked("claim period has passed"));
-        flux.nftClaim(patronNFT, tokenId);
+        flux.nftClaim(patronNFT, tokenId, 0);
     }
 
     function testFluxAccrual() external {