From f9566ae6a781f5782e90a177c5ee38373b1135e6 Mon Sep 17 00:00:00 2001
From: Mubaris NK <mubaris@instadapp.io>
Date: Mon, 29 Mar 2021 17:04:05 +0530
Subject: [PATCH] Add swap borrow rate method

---
 contracts/connectors/aave/v2-amm/events.sol   |  1 +
 .../connectors/aave/v2-amm/interface.sol      |  1 +
 contracts/connectors/aave/v2-amm/main.sol     | 24 ++++++++++++++++++-
 3 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/contracts/connectors/aave/v2-amm/events.sol b/contracts/connectors/aave/v2-amm/events.sol
index 4decffe0..805b2209 100644
--- a/contracts/connectors/aave/v2-amm/events.sol
+++ b/contracts/connectors/aave/v2-amm/events.sol
@@ -6,4 +6,5 @@ contract Events {
     event LogBorrow(address indexed token, uint256 tokenAmt, uint256 indexed rateMode, uint256 getId, uint256 setId);
     event LogPayback(address indexed token, uint256 tokenAmt, uint256 indexed rateMode, uint256 getId, uint256 setId);
     event LogEnableCollateral(address[] tokens);
+    event LogSwapRateMode(address indexed token, uint256 rateMode);
 }
diff --git a/contracts/connectors/aave/v2-amm/interface.sol b/contracts/connectors/aave/v2-amm/interface.sol
index 0d170bf3..ab17fd22 100644
--- a/contracts/connectors/aave/v2-amm/interface.sol
+++ b/contracts/connectors/aave/v2-amm/interface.sol
@@ -12,6 +12,7 @@ interface AaveInterface {
     ) external;
     function repay(address _asset, uint256 _amount, uint256 _rateMode, address _onBehalfOf) external;
     function setUserUseReserveAsCollateral(address _asset, bool _useAsCollateral) external;
+    function swapBorrowRateMode(address _asset, uint256 _rateMode) external;
 }
 
 interface AaveLendingPoolProviderInterface {
diff --git a/contracts/connectors/aave/v2-amm/main.sol b/contracts/connectors/aave/v2-amm/main.sol
index d25fa940..5f89d04a 100644
--- a/contracts/connectors/aave/v2-amm/main.sol
+++ b/contracts/connectors/aave/v2-amm/main.sol
@@ -173,9 +173,31 @@ abstract contract AaveResolver is Events, Helpers {
             }
         }
 
-        _eventName = "LogEnableCollateral(address[]);";
+        _eventName = "LogEnableCollateral(address[])";
         _eventParam = abi.encode(tokens);
     }
+
+    /**
+     * @dev Swap borrow rate mode
+     * @notice Swaps user borrow rate mode between variable and stable
+     * @param token The address of the token to swap borrow rate.(For ETH: 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE)
+     * @param rateMode Desired borrow rate mode. (Stable = 1, Variable = 2)
+    */
+    function swapBorrowRateMode(
+        address token,
+        uint rateMode
+    ) external payable returns (string memory _eventName, bytes memory _eventParam) {
+        AaveInterface aave = AaveInterface(aaveProvider.getLendingPool());
+
+        uint currentRateMode = rateMode == 1 ? 2 : 1;
+
+        if (getPaybackBalance(token, currentRateMode) > 0) {
+            aave.swapBorrowRateMode(token, rateMode);
+        }
+
+        _eventName = "LogSwapRateMode(address,uint256)";
+        _eventParam = abi.encode(token, rateMode);
+    }
 }
 
 contract ConnectV2AaveV2AMM is AaveResolver {