Adding repo concentration limit

src/RepoTokenUtils.sol

@@ -4,10 +4,25 @@ pragma solidity ^0.8.18;
 import {ERC20} from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
 import {ITermRepoToken} from "./interfaces/term/ITermRepoToken.sol";
 
+/*//////////////////////////////////////////////////////////////
+                        LIBRARY: RepoTokenUtils
+//////////////////////////////////////////////////////////////*/
+
 library RepoTokenUtils {
     uint256 public constant THREESIXTY_DAYCOUNT_SECONDS = 360 days;
     uint256 public constant RATE_PRECISION = 1e18;
 
+    /*//////////////////////////////////////////////////////////////
+                        PURE FUNCTIONS
+    //////////////////////////////////////////////////////////////*/
+
+    /**
+     * @notice Convert repoToken amount to purchase token precision
+     * @param repoTokenPrecision The precision of the repoToken
+     * @param purchaseTokenPrecision The precision of the purchase token
+     * @param purchaseTokenAmountInRepoPrecision The amount of purchase token in repoToken precision
+     * @return The amount in purchase token precision
+     */
     function repoToPurchasePrecision(
         uint256 repoTokenPrecision, 
         uint256 purchaseTokenPrecision,
@@ -16,6 +31,13 @@ library RepoTokenUtils {
         return (purchaseTokenAmountInRepoPrecision * purchaseTokenPrecision) / repoTokenPrecision;
     }
 
+    /**
+     * @notice Convert purchase token amount to repoToken precision
+     * @param repoTokenPrecision The precision of the repoToken
+     * @param purchaseTokenPrecision The precision of the purchase token
+     * @param repoTokenAmount The amount of repoToken
+     * @return The amount in repoToken precision
+     */
     function purchaseToRepoPrecision(
         uint256 repoTokenPrecision, 
         uint256 purchaseTokenPrecision,
@@ -24,22 +46,40 @@ library RepoTokenUtils {
         return (repoTokenAmount * repoTokenPrecision) / purchaseTokenPrecision;
     }
 
+    /*//////////////////////////////////////////////////////////////
+                        VIEW FUNCTIONS
+    //////////////////////////////////////////////////////////////*/
+
+    /**
+     * @notice Calculate the present value of a repoToken
+     * @param repoTokenAmountInBaseAssetPrecision The amount of repoToken in base asset precision
+     * @param purchaseTokenPrecision The precision of the purchase token
+     * @param redemptionTimestamp The redemption timestamp of the repoToken
+     * @param discountRate The auction rate
+     * @return presentValue The present value of the repoToken
+     */
     function calculatePresentValue(
         uint256 repoTokenAmountInBaseAssetPrecision,
         uint256 purchaseTokenPrecision, 
         uint256 redemptionTimestamp, 
-        uint256 auctionRate
+        uint256 discountRate
     ) internal view returns (uint256 presentValue) {
         uint256 timeLeftToMaturityDayFraction = 
             ((redemptionTimestamp - block.timestamp) * purchaseTokenPrecision) / THREESIXTY_DAYCOUNT_SECONDS;
 
         // repoTokenAmountInBaseAssetPrecision / (1 + r * days / 360)
         presentValue = 
             (repoTokenAmountInBaseAssetPrecision * purchaseTokenPrecision) / 
-            (purchaseTokenPrecision + (auctionRate * timeLeftToMaturityDayFraction / RATE_PRECISION));
+            (purchaseTokenPrecision + (discountRate * timeLeftToMaturityDayFraction / RATE_PRECISION));
     }
 
-    // returns repo token amount in base asset precision
+    /**
+     * @notice Get the normalized amount of a repoToken in base asset precision
+     * @param repoToken The address of the repoToken
+     * @param repoTokenAmount The amount of the repoToken
+     * @param purchaseTokenPrecision The precision of the purchase token
+     * @return repoTokenAmountInBaseAssetPrecision The normalized amount of the repoToken in base asset precision
+     */
     function getNormalizedRepoTokenAmount(
         address repoToken, 
         uint256 repoTokenAmount, 
@@ -51,4 +91,4 @@ library RepoTokenUtils {
             (redemptionValue * repoTokenAmount * purchaseTokenPrecision) / 
             (repoTokenPrecision * RepoTokenUtils.RATE_PRECISION);
     }
-}
+}