Added curve gauge resolver

contracts/protocols/curveGauge.sol

@@ -0,0 +1,97 @@
+pragma solidity ^0.6.0;
+pragma experimental ABIEncoderV2;
+
+interface ICurveGaugeMapping {
+
+  struct GaugeData {
+    address gaugeAddress;
+    bool rewardToken;
+  }
+
+  function gaugeMapping(bytes32) external view returns(GaugeData memory);
+}
+
+interface TokenInterface {
+    function balanceOf(address) external view returns (uint);
+}
+
+interface IMintor {
+    function minted(address, address) external view returns (uint);
+}
+
+interface IGauge {
+  function integrate_fraction(address user) external view returns(uint256 amt);
+  function lp_token() external view returns(address token);
+  function rewarded_token() external view returns(address token);
+  function crv_token() external view returns(address token);
+  function balanceOf(address user) external view returns(uint256 amt);
+  function rewards_for(address user) external view returns(uint256 amt);
+  function claimed_rewards_for(address user) external view returns(uint256 amt);
+}
+
+contract GaugeHelper {
+  function getCurveGaugeMappingAddr() internal pure returns (address){
+    return 0x1C800eF1bBfE3b458969226A96c56B92a069Cc92;
+  }
+
+  function getCurveMintorAddr() internal pure returns (address){
+    return 0xd061D61a4d941c39E5453435B6345Dc261C2fcE0;
+  }
+
+  /**
+   * @dev Convert String to bytes32.
+   */
+  function stringToBytes32(string memory str) internal pure returns (bytes32 result) {
+    require(bytes(str).length != 0, "string-empty");
+    // solium-disable-next-line security/no-inline-assembly
+    assembly {
+      result := mload(add(str, 32))
+    }
+  }
+}
+
+
+contract Resolver is GaugeHelper {
+    struct PositionData {
+        uint stakedBal;
+        uint crvEarned;
+        uint crvClaimed;
+        uint rewardsEarned;
+        uint rewardsClaimed;
+        uint crvBal;
+        uint rewardBal;
+        bool hasReward;
+    }
+    function getPosition(string memory gaugeName, address user) public view returns (PositionData memory positionData) { 
+        ICurveGaugeMapping curveGaugeMapping = ICurveGaugeMapping(getCurveGaugeMappingAddr());
+        ICurveGaugeMapping.GaugeData memory curveGaugeData = curveGaugeMapping.gaugeMapping(
+            bytes32(stringToBytes32(gaugeName)
+        ));
+        IGauge gauge = IGauge(curveGaugeData.gaugeAddress);
+        IMintor mintor = IMintor(getCurveMintorAddr());
+        positionData.stakedBal = gauge.balanceOf(user);
+        positionData.crvEarned = gauge.integrate_fraction(user);
+        positionData.crvClaimed = mintor.minted(user, address(gauge));
+
+        if (curveGaugeData.rewardToken) {
+            positionData.rewardsEarned = gauge.rewards_for(user);
+            positionData.rewardsClaimed = gauge.claimed_rewards_for(user);
+            positionData.rewardBal = TokenInterface(address(gauge.rewarded_token())).balanceOf(user);
+        }
+        positionData.hasReward = curveGaugeData.rewardToken;
+
+        positionData.crvBal = TokenInterface(address(gauge.crv_token())).balanceOf(user);
+    }
+
+    function getPositions(string[] memory gaugesName, address user) public view returns (PositionData[] memory positions) {
+        positions = new PositionData[](gaugesName.length);
+        for (uint i = 0; i < gaugesName.length; i++) {
+            positions[i] = getPosition(gaugesName[i], user);
+        }
+    }
+}
+
+
+contract InstaCurveGaugeResolver is Resolver {
+    string public constant name = "Curve-Gauge-Resolver-v1";
+}