Add farmer tax to contracts with TaxCollector

clean_build/contracts/FarmPool.json

@@ -0,0 +1 @@
+{"abi": [{"constant": false, "inputs": [], "name": "withdrawTax", "outputs": [], "payable": false, "stateMutability": "nonpayable", "type": "function"}], "networks": {}}

clean_build/contracts/HAMTaxCollector.json

@@ -0,0 +1 @@
+{"abi": [{"inputs": [{"internalType": "address", "name": "uniFactory_", "type": "address"}, {"internalType": "address", "name": "uniRouter_", "type": "address"}, {"internalType": "address", "name": "hamToken_", "type": "address"}, {"internalType": "address", "name": "beneficiary_", "type": "address"}, {"internalType": "address[]", "name": "farms", "type": "address[]"}], "payable": false, "stateMutability": "nonpayable", "type": "constructor"}, {"anonymous": false, "inputs": [{"indexed": false, "internalType": "uint256", "name": "amountIn", "type": "uint256"}, {"indexed": false, "internalType": "uint256", "name": "amountOut", "type": "uint256"}], "name": "TaxesCollected", "type": "event"}, {"constant": true, "inputs": [], "name": "beneficiary", "outputs": [{"internalType": "address", "name": "", "type": "address"}], "payable": false, "stateMutability": "view", "type": "function"}, {"constant": true, "inputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "name": "farmsToTax", "outputs": [{"internalType": "address", "name": "", "type": "address"}], "payable": false, "stateMutability": "view", "type": "function"}, {"constant": true, "inputs": [], "name": "hamToken", "outputs": [{"internalType": "contract HamToken", "name": "", "type": "address"}], "payable": false, "stateMutability": "view", "type": "function"}, {"constant": true, "inputs": [], "name": "uniFactory", "outputs": [{"internalType": "address", "name": "", "type": "address"}], "payable": false, "stateMutability": "view", "type": "function"}, {"constant": true, "inputs": [], "name": "uniRouter", "outputs": [{"internalType": "address", "name": "", "type": "address"}], "payable": false, "stateMutability": "view", "type": "function"}, {"constant": true, "inputs": [], "name": "weth", "outputs": [{"internalType": "address", "name": "", "type": "address"}], "payable": false, "stateMutability": "view", "type": "function"}, {"constant": false, "inputs": [{"internalType": "address", "name": "farm", "type": "address"}], "name": "addFarm", "outputs": [], "payable": false, "stateMutability": "nonpayable", "type": "function"}, {"constant": false, "inputs": [], "name": "collectTaxes", "outputs": [], "payable": false, "stateMutability": "nonpayable", "type": "function"}], "networks": {}}

clean_build/contracts/HamToken.json

@@ -0,0 +1 @@
+{"abi": [{"constant": false, "inputs": [{"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "value", "type": "uint256"}], "name": "transfer", "outputs": [{"internalType": "bool", "name": "", "type": "bool"}], "payable": false, "stateMutability": "nonpayable", "type": "function"}, {"constant": false, "inputs": [{"internalType": "address", "name": "from", "type": "address"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "value", "type": "uint256"}], "name": "transferFrom", "outputs": [{"internalType": "bool", "name": "", "type": "bool"}], "payable": false, "stateMutability": "nonpayable", "type": "function"}, {"constant": true, "inputs": [{"internalType": "address", "name": "who", "type": "address"}], "name": "balanceOf", "outputs": [{"internalType": "uint256", "name": "", "type": "uint256"}], "payable": false, "stateMutability": "view", "type": "function"}], "networks": {}}

clean_build/contracts/IUniswapV2Router01.json

@@ -0,0 +1 @@
+{"abi": [{"constant": false, "inputs": [{"internalType": "uint256", "name": "amountIn", "type": "uint256"}, {"internalType": "uint256", "name": "amountOutMin", "type": "uint256"}, {"internalType": "address[]", "name": "path", "type": "address[]"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "swapExactTokensForTokens", "outputs": [{"internalType": "uint256[]", "name": "amounts", "type": "uint256[]"}], "payable": false, "stateMutability": "nonpayable", "type": "function"}, {"constant": false, "inputs": [{"internalType": "uint256", "name": "amountOut", "type": "uint256"}, {"internalType": "uint256", "name": "amountInMax", "type": "uint256"}, {"internalType": "address[]", "name": "path", "type": "address[]"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "swapTokensForExactETH", "outputs": [{"internalType": "uint256[]", "name": "amounts", "type": "uint256[]"}], "payable": false, "stateMutability": "nonpayable", "type": "function"}, {"constant": false, "inputs": [{"internalType": "uint256", "name": "amountIn", "type": "uint256"}, {"internalType": "uint256", "name": "amountOutMin", "type": "uint256"}, {"internalType": "address[]", "name": "path", "type": "address[]"}, {"internalType": "address", "name": "to", "type": "address"}, {"internalType": "uint256", "name": "deadline", "type": "uint256"}], "name": "swapExactTokensForETH", "outputs": [{"internalType": "uint256[]", "name": "amounts", "type": "uint256[]"}], "payable": false, "stateMutability": "nonpayable", "type": "function"}, {"constant": true, "inputs": [{"internalType": "uint256", "name": "amountA", "type": "uint256"}, {"internalType": "uint256", "name": "reserveA", "type": "uint256"}, {"internalType": "uint256", "name": "reserveB", "type": "uint256"}], "name": "quote", "outputs": [{"internalType": "uint256", "name": "amountB", "type": "uint256"}], "payable": false, "stateMutability": "pure", "type": "function"}, {"constant": true, "inputs": [{"internalType": "uint256", "name": "amountIn", "type": "uint256"}, {"internalType": "uint256", "name": "reserveIn", "type": "uint256"}, {"internalType": "uint256", "name": "reserveOut", "type": "uint256"}], "name": "getAmountOut", "outputs": [{"internalType": "uint256", "name": "amountOut", "type": "uint256"}], "payable": false, "stateMutability": "pure", "type": "function"}], "networks": {}}

clean_build/contracts/UniswapV2Library.json

@@ -0,0 +1 @@
+{"abi": [], "networks": {}}

contracts/distribution/HAMLENDPool.sol

@@ -592,8 +592,6 @@ interface HAM {
     function hamsScalingFactor() external returns (uint256);
 }
 
-
-
 contract LPTokenWrapper {
     using SafeMath for uint256;
     using SafeERC20 for IERC20;
@@ -633,13 +631,16 @@ contract HAMLENDPool is LPTokenWrapper, IRewardDistributionRecipient {
     uint256 public rewardRate = 0;
     uint256 public lastUpdateTime;
     uint256 public rewardPerTokenStored;
+    uint256 public tokensFromTax;
+    address public taxCollector;
     mapping(address => uint256) public userRewardPerTokenPaid;
     mapping(address => uint256) public rewards;
 
     event RewardAdded(uint256 reward);
     event Staked(address indexed user, uint256 amount);
     event Withdrawn(address indexed user, uint256 amount);
     event RewardPaid(address indexed user, uint256 reward);
+    event TaxWithdrawn(address indexed beneficiary, uint256 reward);
 
     modifier checkStart() {
         require(block.timestamp >= starttime,"not start");
@@ -656,6 +657,11 @@ contract HAMLENDPool is LPTokenWrapper, IRewardDistributionRecipient {
         _;
     }
 
+    function setTaxCollector(address newCollector) external onlyOwner {
+        require(newCollector != address(0x0), "!nonzero");
+        taxCollector = newCollector;
+    }
+
     function lastTimeRewardApplicable() public view returns (uint256) {
         return Math.min(block.timestamp, periodFinish);
     }
@@ -704,34 +710,48 @@ contract HAMLENDPool is LPTokenWrapper, IRewardDistributionRecipient {
         uint256 reward = earned(msg.sender);
         if (reward > 0) {
             rewards[msg.sender] = 0;
+            uint256 tax = reward.div(100);
+            tokensFromTax = tokensFromTax.add(tax);
             uint256 scalingFactor = HAM(address(ham)).hamsScalingFactor();
-            uint256 trueReward = reward.mul(scalingFactor).div(10**18);
+            uint256 trueReward = reward.sub(tax).mul(scalingFactor).div(10**18);
             ham.safeTransfer(msg.sender, trueReward);
             emit RewardPaid(msg.sender, trueReward);
         }
     }
 
+    function withdrawTax() public checkStart {
+        require(msg.sender == taxCollector, "!taxCollector");
+        uint256 tokens = tokensFromTax;
+        if (tokens > 0) {
+            tokensFromTax = 0;
+            uint256 scalingFactor = HAM(address(ham)).hamsScalingFactor();
+            uint256 collectedTax = tokens.mul(scalingFactor).div(10**18);
+            ham.safeTransfer(taxCollector, collectedTax);
+            emit TaxWithdrawn(taxCollector, collectedTax);
+        }
+    }
+
     function notifyRewardAmount(uint256 reward)
         external
         onlyRewardDistribution
         updateReward(address(0))
     {
         if (block.timestamp > starttime) {
-          if (block.timestamp >= periodFinish) {
-              rewardRate = reward.div(DURATION);
-          } else {
-              uint256 remaining = periodFinish.sub(block.timestamp);
-              uint256 leftover = remaining.mul(rewardRate);
-              rewardRate = reward.add(leftover).div(DURATION);
-          }
-          lastUpdateTime = block.timestamp;
-          periodFinish = block.timestamp.add(DURATION);
-          emit RewardAdded(reward);
+            if (block.timestamp >= periodFinish) {
+                rewardRate = reward.div(DURATION);
+            } else {
+                uint256 remaining = periodFinish.sub(block.timestamp);
+                uint256 leftover = remaining.mul(rewardRate);
+                rewardRate = reward.add(leftover).div(DURATION);
+            }
+            lastUpdateTime = block.timestamp;
+            periodFinish = block.timestamp.add(DURATION);
+            emit RewardAdded(reward);
         } else {
-          rewardRate = reward.div(DURATION);
-          lastUpdateTime = starttime;
-          periodFinish = starttime.add(DURATION);
-          emit RewardAdded(reward);
+            rewardRate = reward.div(DURATION);
+            lastUpdateTime = starttime;
+            periodFinish = starttime.add(DURATION);
+            emit RewardAdded(reward);
         }
     }
 }

contracts/lib/UniswapV2Library.sol

@@ -0,0 +1,81 @@
+pragma solidity >=0.5.0;
+
+import './IUniswapV2Pair.sol';
+import "./SafeMath.sol";
+
+library UniswapV2Library {
+    using SafeMath for uint;
+
+    // returns sorted token addresses, used to handle return values from pairs sorted in this order
+    function sortTokens(address tokenA, address tokenB) internal pure returns (address token0, address token1) {
+        require(tokenA != tokenB, 'UniswapV2Library: IDENTICAL_ADDRESSES');
+        (token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
+        require(token0 != address(0), 'UniswapV2Library: ZERO_ADDRESS');
+    }
+
+    // calculates the CREATE2 address for a pair without making any external calls
+    function pairFor(address factory, address tokenA, address tokenB) internal pure returns (address pair) {
+        (address token0, address token1) = sortTokens(tokenA, tokenB);
+        pair = address(uint(keccak256(abi.encodePacked(
+                hex'ff',
+                factory,
+                keccak256(abi.encodePacked(token0, token1)),
+                hex'96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f' // init code hash
+            ))));
+    }
+
+    // fetches and sorts the reserves for a pair
+    function getReserves(address factory, address tokenA, address tokenB) internal view returns (uint reserveA, uint reserveB) {
+        (address token0,) = sortTokens(tokenA, tokenB);
+        (uint reserve0, uint reserve1,) = UniswapPair(pairFor(factory, tokenA, tokenB)).getReserves();
+        (reserveA, reserveB) = tokenA == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
+    }
+
+    // given some amount of an asset and pair reserves, returns an equivalent amount of the other asset
+    function quote(uint amountA, uint reserveA, uint reserveB) internal pure returns (uint amountB) {
+        require(amountA > 0, 'UniswapV2Library: INSUFFICIENT_AMOUNT');
+        require(reserveA > 0 && reserveB > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
+        amountB = amountA.mul(reserveB) / reserveA;
+    }
+
+    // given an input amount of an asset and pair reserves, returns the maximum output amount of the other asset
+    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) internal pure returns (uint amountOut) {
+        require(amountIn > 0, 'UniswapV2Library: INSUFFICIENT_INPUT_AMOUNT');
+        require(reserveIn > 0 && reserveOut > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
+        uint amountInWithFee = amountIn.mul(997);
+        uint numerator = amountInWithFee.mul(reserveOut);
+        uint denominator = reserveIn.mul(1000).add(amountInWithFee);
+        amountOut = numerator / denominator;
+    }
+
+    // given an output amount of an asset and pair reserves, returns a required input amount of the other asset
+    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) internal pure returns (uint amountIn) {
+        require(amountOut > 0, 'UniswapV2Library: INSUFFICIENT_OUTPUT_AMOUNT');
+        require(reserveIn > 0 && reserveOut > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
+        uint numerator = reserveIn.mul(amountOut).mul(1000);
+        uint denominator = reserveOut.sub(amountOut).mul(997);
+        amountIn = (numerator / denominator).add(1);
+    }
+
+    // performs chained getAmountOut calculations on any number of pairs
+    function getAmountsOut(address factory, uint amountIn, address[] memory path) internal view returns (uint[] memory amounts) {
+        require(path.length >= 2, 'UniswapV2Library: INVALID_PATH');
+        amounts = new uint[](path.length);
+        amounts[0] = amountIn;
+        for (uint i; i < path.length - 1; i++) {
+            (uint reserveIn, uint reserveOut) = getReserves(factory, path[i], path[i + 1]);
+            amounts[i + 1] = getAmountOut(amounts[i], reserveIn, reserveOut);
+        }
+    }
+
+    // performs chained getAmountIn calculations on any number of pairs
+    function getAmountsIn(address factory, uint amountOut, address[] memory path) internal view returns (uint[] memory amounts) {
+        require(path.length >= 2, 'UniswapV2Library: INVALID_PATH');
+        amounts = new uint[](path.length);
+        amounts[amounts.length - 1] = amountOut;
+        for (uint i = path.length - 1; i > 0; i--) {
+            (uint reserveIn, uint reserveOut) = getReserves(factory, path[i - 1], path[i]);
+            amounts[i - 1] = getAmountIn(amounts[i], reserveIn, reserveOut);
+        }
+    }
+}

contracts/lib/UniswapV2OracleLibrary.sol

@@ -20,27 +20,26 @@ library UniswapV2OracleLibrary {
         blockTimestamp = currentBlockTimestamp();
         (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast) = UniswapPair(pair).getReserves();
         if (isToken0) {
-          priceCumulative = UniswapPair(pair).price0CumulativeLast();
+            priceCumulative = UniswapPair(pair).price0CumulativeLast();
 
-          // if time has elapsed since the last update on the pair, mock the accumulated price values
-          if (blockTimestampLast != blockTimestamp) {
-              // subtraction overflow is desired
-              uint32 timeElapsed = blockTimestamp - blockTimestampLast;
-              // addition overflow is desired
-              // counterfactual
-              priceCumulative += uint(FixedPoint.fraction(reserve1, reserve0)._x) * timeElapsed;
-          }
+            // if time has elapsed since the last update on the pair, mock the accumulated price values
+            if (blockTimestampLast != blockTimestamp) {
+                // subtraction overflow is desired
+                uint32 timeElapsed = blockTimestamp - blockTimestampLast;
+                // addition overflow is desired
+                // counterfactual
+                priceCumulative += uint(FixedPoint.fraction(reserve1, reserve0)._x) * timeElapsed;
+            }
         } else {
-          priceCumulative = UniswapPair(pair).price1CumulativeLast();
-          // if time has elapsed since the last update on the pair, mock the accumulated price values
-          if (blockTimestampLast != blockTimestamp) {
-              // subtraction overflow is desired
-              uint32 timeElapsed = blockTimestamp - blockTimestampLast;
-              // addition overflow is desired
-              // counterfactual
-              priceCumulative += uint(FixedPoint.fraction(reserve0, reserve1)._x) * timeElapsed;
-          }
+            priceCumulative = UniswapPair(pair).price1CumulativeLast();
+            // if time has elapsed since the last update on the pair, mock the accumulated price values
+            if (blockTimestampLast != blockTimestamp) {
+                // subtraction overflow is desired
+                uint32 timeElapsed = blockTimestamp - blockTimestampLast;
+                // addition overflow is desired
+                // counterfactual
+                priceCumulative += uint(FixedPoint.fraction(reserve0, reserve1)._x) * timeElapsed;
+            }
         }
-
     }
 }