feat: add fluid contracts

contracts/mainnet/connectors/fluid/events.sol

@@ -0,0 +1,14 @@
+//SPDX-License-Identifier: MIT
+pragma solidity ^0.7.0;
+
+contract Events {
+    event LogOperate (
+        address vaultAddress,
+        uint256 nftId,
+        int256 newCol,
+        int256 newDebt,
+        address to,
+		uint256 getId,
+		uint256 setId
+    );
+}

contracts/mainnet/connectors/fluid/interface.sol

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+//SPDX-License-Identifier: MIT
+pragma solidity ^0.7.0;
+pragma experimental ABIEncoderV2;
+
+interface IVault {
+    
+    /// @dev Single function which handles supply, withdraw, borrow & payback
+    /// @param nftId_ NFT ID for interaction. If 0 then create new NFT/position.
+    /// @param newCol_ new collateral. If positive then deposit, if negative then withdraw, if 0 then do nohing
+    /// @param newDebt_ new debt. If positive then borrow, if negative then payback, if 0 then do nohing
+    /// @param to_ address where withdraw or borrow should go. If address(0) then msg.sender
+    /// @return nftId_ if 0 then this returns the newly created NFT Id else returns the same NFT ID
+    /// @return final supply amount. Mainly if max withdraw using type(int).min then this is useful to get perfect amount else remain same as newCol_
+    /// @return final borrow amount. Mainly if max payback using type(int).min then this is useful to get perfect amount else remain same as newDebt_
+    function operate(
+        uint256 nftId_, // if 0 then new position
+        int256 newCol_, // if negative then withdraw
+        int256 newDebt_, // if negative then payback
+        address to_ // address at which the borrow & withdraw amount should go to. If address(0) then it'll go to msg.sender
+    )
+        external
+        returns (
+            uint256, // nftId_
+            int256, // final supply amount if - then withdraw
+            int256 // final borrow amount if - then payback
+        );
+
+    struct ConstantViews {
+        address liquidity;
+        address factory;
+        address adminImplementation;
+        address secondaryImplementation;
+        address supplyToken;
+        address borrowToken;
+        uint8 supplyDecimals;
+        uint8 borrowDecimals;
+        uint vaultId;
+        bytes32 liquidityTotalSupplySlot;
+        bytes32 liquidityTotalBorrowSlot;
+        bytes32 liquiditySupplyExchangePriceSlot;
+        bytes32 liquidityBorrowExchangePriceSlot;
+        bytes32 liquidityUserSupplySlot;
+        bytes32 liquidityUserBorrowSlot;
+    }
+
+    function constantsView() external view returns (ConstantViews memory constantsView_);
+}

contracts/mainnet/connectors/fluid/main.sol

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+//SPDX-License-Identifier: MIT
+pragma solidity ^0.7.0;
+
+/**
+ * @title Fluid.
+ * @dev Lending & Borrowing.
+ */
+
+import { Stores } from "../../common/stores.sol";
+import { Events } from "./events.sol";
+import { IVault } from "./interface.sol";
+
+abstract contract FluidConnector is Events, Stores {
+    // todo: add logics when user wants to deposit weth
+
+    function operate(
+        address vaultAddress_,
+        uint256 nftId_, // if 0 then new position
+        int256 newCol_, // if negative then withdraw
+        int256 newDebt_, // if negative then payback
+        address to_,
+		uint256 getId_,
+		uint256 setId_
+    ) external payable
+		returns (string memory _eventName, bytes memory _eventParam) 
+    {
+        nftId_ = getUint(getId_, nftId_);
+
+        IVault vault_ = IVault(vaultAddress_);
+
+        IVault.ConstantViews memory vaultDetails_ = vault_.constantsView();
+
+        (nftId_, newCol_, newDebt_) = vault_.operate(nftId_, newCol_, newDebt_, to_);
+
+        setUint(setId_, nftId_);
+
+        _eventName = "LogOperate(address,uint256,uint256,uint256,address,uint256,uint256)";
+		_eventParam = abi.encode(vaultAddress_, nftId_, newCol_, newDebt_, to_, getId_, setId_);
+    }
+}
+
+contract ConnectV2Fluid is FluidConnector {
+	string public constant name = "Fluid-v1.0";
+}