intermediate

ampleforth · Dec 29, 2022 · 4a1c8de · 4a1c8de
1 parent 515a658
commit 4a1c8de
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Showing 5 changed files with 561 additions and 168 deletions.
diff --git a/spot-contracts/contracts/_utils/BondHelpers.sol b/spot-contracts/contracts/_utils/BondHelpers.sol
@@ -191,27 +191,33 @@ library BondHelpers {
         return (td, collateralBalances, trancheSupplies);
     }
 
-    /// @notice Given a bond, retrieves the collateral redeemable for
-    ///         each tranche held by the given address.
+    /// @notice Given a bond and a user address computes the tranche amounts proportional to the tranche ratios,
+    //          that can be redeemed for the collateral before maturity.
     /// @param b The address of the bond contract.
     /// @param u The address to check balance for.
-    /// @return The tranche data and an array of collateral balances.
-    function getTrancheCollateralBalances(IBondController b, address u)
+    /// @return The tranche data and an array of tranche token balances.
+    function computeRedeemableTrancheAmounts(IBondController b, address u)
         internal
         view
         returns (TrancheData memory, uint256[] memory)
     {
-        TrancheData memory td;
-        uint256[] memory collateralBalances;
-        uint256[] memory trancheSupplies;
-
-        (td, collateralBalances, trancheSupplies) = getTrancheCollateralizations(b);
+        TrancheData memory td = getTrancheData(b);
+        uint256[] memory redeemableAmts = new uint256[](td.trancheCount);
+
+        // We calculate the minimum value of {trancheBal/trancheRatio} across tranches
+        uint256 min = type(uint256).max;
+        uint8 i;
+        for (i = 0; i < td.trancheCount && min != 0; i++) {
+            uint256 d = (td.tranches[i].balanceOf(u) * TRANCHE_RATIO_GRANULARITY) / td.trancheRatios[i];
+            if (d < min) {
+                min = d;
+            }
+        }
 
-        uint256[] memory balances = new uint256[](td.trancheCount);
-        for (uint8 i = 0; i < td.trancheCount; i++) {
-            balances[i] = (td.tranches[i].balanceOf(u) * collateralBalances[i]) / trancheSupplies[i];
+        for (i = 0; i < td.trancheCount; i++) {
+            redeemableAmts[i] = (td.trancheRatios[i] * min) / TRANCHE_RATIO_GRANULARITY;
         }
 
-        return (td, balances);
+        return (td, redeemableAmts);
     }
 }
diff --git a/spot-contracts/contracts/test/BondHelpersTester.sol b/spot-contracts/contracts/test/BondHelpersTester.sol
@@ -33,14 +33,6 @@ contract BondHelpersTester {
         return b.previewDeposit(collateralAmount);
     }
 
-    function getTrancheCollateralBalances(IBondController b, address u)
-        public
-        view
-        returns (TrancheData memory, uint256[] memory)
-    {
-        return b.getTrancheCollateralBalances(u);
-    }
-
     function getTrancheCollateralizations(IBondController b)
         public
         view
@@ -57,4 +49,12 @@ contract BondHelpersTester {
         TrancheData memory td = b.getTrancheData();
         return td.getTrancheIndex(t);
     }
+
+    function computeRedeemableTrancheAmounts(IBondController b, address u)
+        public
+        view
+        returns (TrancheData memory td, uint256[] memory)
+    {
+        return b.computeRedeemableTrancheAmounts(u);
+    }
 }
diff --git a/spot-contracts/contracts/test/mocks/MockPerpetualTranche.sol b/spot-contracts/contracts/test/mocks/MockPerpetualTranche.sol
@@ -7,6 +7,7 @@ contract MockPerpetualTranche is MockERC20 {
     uint256 private _reserveTrancheBalance;
     uint256 public matureTrancheBalance;
     address public collateral;
+    address public feeToken;
 
     function protocolFeeCollector() public view returns (address) {
         return address(this);
@@ -29,4 +30,8 @@ contract MockPerpetualTranche is MockERC20 {
     function setCollateral(address c) external {
         collateral = c;
     }
+
+    function setFeeToken(address c) external {
+        feeToken = c;
+    }
 }