From 2d103a4607ffa22e3170fecb3f1cdcfaf81a2a77 Mon Sep 17 00:00:00 2001
From: Brice Stacey <brice@m2.xyz>
Date: Thu, 6 Oct 2022 14:14:57 -0400
Subject: [PATCH] Emit LoanFunded and LoanDrawnDown events

---
 contracts/FundingVault.sol      | 10 +++++-----
 contracts/Pool.sol              |  6 +++++-
 contracts/interfaces/ILoan.sol  | 10 ++++++++++
 contracts/libraries/LoanLib.sol | 12 ++++++++++++
 test/Loan.test.ts               | 29 ++++++++++++++++++++++++++---
 5 files changed, 58 insertions(+), 9 deletions(-)

diff --git a/contracts/FundingVault.sol b/contracts/FundingVault.sol
index 290abbfa..12949247 100644
--- a/contracts/FundingVault.sol
+++ b/contracts/FundingVault.sol
@@ -13,7 +13,7 @@ contract FundingVault {
     using SafeERC20 for IERC20;
 
     address private immutable _loan;
-    IERC20 private immutable _asset;
+    IERC20 public immutable asset;
 
     /**
      * @dev Modifier restricting access to pool
@@ -26,11 +26,11 @@ contract FundingVault {
     /**
      * @dev Constructor for the vault
      * @param loan address of loan
-     * @param asset asset held by vault
+     * @param asset_ asset held by vault
      */
-    constructor(address loan, address asset) {
+    constructor(address loan, address asset_) {
         _loan = loan;
-        _asset = IERC20(asset);
+        asset = IERC20(asset_);
     }
 
     /**
@@ -38,6 +38,6 @@ contract FundingVault {
      */
     function withdraw(uint256 amount, address receiver) external onlyLoan {
         require(receiver != address(0), "FundingVault: 0 address");
-        _asset.safeTransfer(receiver, amount);
+        asset.safeTransfer(receiver, amount);
     }
 }
diff --git a/contracts/Pool.sol b/contracts/Pool.sol
index c999d688..a3c5d237 100644
--- a/contracts/Pool.sol
+++ b/contracts/Pool.sol
@@ -216,7 +216,11 @@ contract Pool is IPool, ERC20 {
     /**
      * @dev Called by the pool manager, this transfers liquidity from the pool to a given loan.
      */
-    function fundLoan(address addr) external onlyManager {
+    function fundLoan(address addr)
+        external
+        onlyManager
+        atState(IPoolLifeCycleState.Active)
+    {
         ILoan loan = ILoan(addr);
 
         _liquidityAsset.safeApprove(address(loan), loan.principal());
diff --git a/contracts/interfaces/ILoan.sol b/contracts/interfaces/ILoan.sol
index c0eb8577..955fecdf 100644
--- a/contracts/interfaces/ILoan.sol
+++ b/contracts/interfaces/ILoan.sol
@@ -26,6 +26,16 @@ struct ILoanNonFungibleCollateral {
 }
 
 interface ILoan {
+    /**
+     * @dev Emitted when loan is funded.
+     */
+    event LoanFunded(address asset, uint256 amount);
+
+    /**
+     * @dev Emitted when the loan is drawn down.
+     */
+    event LoanDrawnDown(address asset, uint256 amount);
+
     /**
      * @dev Emitted when collateral is posted to the loan.
      */
diff --git a/contracts/libraries/LoanLib.sol b/contracts/libraries/LoanLib.sol
index 4b829a2b..71400e7a 100644
--- a/contracts/libraries/LoanLib.sol
+++ b/contracts/libraries/LoanLib.sol
@@ -15,6 +15,16 @@ library LoanLib {
     using SafeERC20 for IERC20;
     using SafeMath for uint256;
 
+    /**
+     * @dev Emitted when loan is funded.
+     */
+    event LoanFunded(address asset, uint256 amount);
+
+    /**
+     * @dev Emitted when the loan is drawn down.
+     */
+    event LoanDrawnDown(address asset, uint256 amount);
+
     /**
      * @dev Emitted when collateral is posted to the loan.
      */
@@ -168,6 +178,7 @@ library LoanLib {
             address(fundingVault),
             amount
         );
+        emit LoanFunded(liquidityAsset, amount);
         return ILoanLifeCycleState.Funded;
     }
 
@@ -180,5 +191,6 @@ library LoanLib {
         address receiver
     ) public {
         fundingVault.withdraw(amount, receiver);
+        emit LoanDrawnDown(address(fundingVault.asset()), amount);
     }
 }
diff --git a/test/Loan.test.ts b/test/Loan.test.ts
index 73eb5703..62f979ea 100644
--- a/test/Loan.test.ts
+++ b/test/Loan.test.ts
@@ -360,7 +360,8 @@ describe("Loan", () => {
     it("transitions Loan to Funded state", async () => {
       const fixture = await loadFixture(deployFixture);
       let { loan } = fixture;
-      const { borrower, collateralAsset, pool, poolManager } = fixture;
+      const { borrower, collateralAsset, liquidityAsset, pool, poolManager } =
+        fixture;
 
       // Connect as borrower
       loan = loan.connect(borrower);
@@ -370,8 +371,22 @@ describe("Loan", () => {
       await expect(loan.postFungibleCollateral(collateralAsset.address, 100))
         .not.to.be.reverted;
       expect(await loan.state()).to.equal(1);
-      await expect(pool.connect(poolManager).fundLoan(loan.address)).not.to.be
-        .reverted;
+      const fundTx = pool.connect(poolManager).fundLoan(loan.address);
+      await expect(fundTx).not.to.be.reverted;
+      await expect(fundTx)
+        .to.emit(loan, "LoanFunded")
+        .withArgs(loan.liquidityAsset, 500_000);
+      await expect(fundTx).to.changeTokenBalance(
+        liquidityAsset,
+        await loan.fundingVault(),
+        500_000
+      );
+      await expect(fundTx).to.changeTokenBalance(
+        liquidityAsset,
+        pool,
+        -500_000
+      );
+
       expect(await loan.state()).to.equal(4);
     });
 
@@ -436,6 +451,14 @@ describe("Loan", () => {
         borrower.address,
         500_000
       );
+      await expect(drawDownTx).to.changeTokenBalance(
+        liquidityAsset,
+        await loan.fundingVault(),
+        -500_000
+      );
+      await expect(drawDownTx)
+        .to.emit(loan, "LoanDrawnDown")
+        .withArgs(loan.liquidityAsset, 500_000);
 
       // Try again
       const drawDownTx2 = loan.connect(borrower).drawdown();