refactor: Improve precision in hub.restore()

snapshots/Hub.Operations.json

@@ -1,18 +1,18 @@
 {
-  "add": "86660",
-  "add: with transfer": "107957",
-  "draw": "104177",
-  "eliminateDeficit: full": "72422",
-  "eliminateDeficit: partial": "82027",
-  "mintFeeShares": "82721",
-  "payFee": "70834",
-  "refreshPremium": "70391",
-  "remove: full": "75451",
-  "remove: partial": "80589",
-  "reportDeficit": "111899",
-  "restore: full": "76569",
-  "restore: full - with transfer": "169178",
-  "restore: partial": "85291",
-  "restore: partial - with transfer": "143271",
-  "transferShares": "69648"
+  "add": "86654",
+  "add: with transfer": "107951",
+  "draw": "104159",
+  "eliminateDeficit: full": "72416",
+  "eliminateDeficit: partial": "82021",
+  "mintFeeShares": "82703",
+  "payFee": "70816",
+  "refreshPremium": "70373",
+  "remove: full": "75445",
+  "remove: partial": "80583",
+  "reportDeficit": "111893",
+  "restore: full": "76563",
+  "restore: full - with transfer": "169172",
+  "restore: partial": "85273",
+  "restore: partial - with transfer": "143253",
+  "transferShares": "69630"
 }

snapshots/NativeTokenGateway.Operations.json

@@ -1,8 +1,8 @@
 {
-  "borrowNative": "227759",
-  "repayNative": "166193",
-  "supplyAsCollateralNative": "160052",
-  "supplyNative": "135728",
-  "withdrawNative: full": "125393",
-  "withdrawNative: partial": "136541"
+  "borrowNative": "228479",
+  "repayNative": "166471",
+  "supplyAsCollateralNative": "160046",
+  "supplyNative": "135723",
+  "withdrawNative: full": "125388",
+  "withdrawNative: partial": "136535"
 }

snapshots/SignatureGateway.Operations.json

@@ -1,10 +1,10 @@
 {
-  "borrowWithSig": "212949",
-  "repayWithSig": "186465",
+  "borrowWithSig": "213712",
+  "repayWithSig": "186743",
   "setSelfAsUserPositionManagerWithSig": "75385",
   "setUsingAsCollateralWithSig": "85349",
-  "supplyWithSig": "151960",
-  "updateUserDynamicConfigWithSig": "63086",
-  "updateUserRiskPremiumWithSig": "62056",
-  "withdrawWithSig": "130648"
+  "supplyWithSig": "151955",
+  "updateUserDynamicConfigWithSig": "63111",
+  "updateUserRiskPremiumWithSig": "62081",
+  "withdrawWithSig": "130643"
 }

snapshots/Spoke.Getters.json

@@ -1,7 +1,7 @@
 {
-  "getUserAccountData: supplies: 0, borrows: 0": "12962",
-  "getUserAccountData: supplies: 1, borrows: 0": "49251",
-  "getUserAccountData: supplies: 2, borrows: 0": "80826",
-  "getUserAccountData: supplies: 2, borrows: 1": "100237",
-  "getUserAccountData: supplies: 2, borrows: 2": "118994"
+  "getUserAccountData: supplies: 0, borrows: 0": "12987",
+  "getUserAccountData: supplies: 1, borrows: 0": "49318",
+  "getUserAccountData: supplies: 2, borrows: 0": "80914",
+  "getUserAccountData: supplies: 2, borrows: 1": "101283",
+  "getUserAccountData: supplies: 2, borrows: 2": "120512"
 }

snapshots/Spoke.Operations.ZeroRiskPremium.json

@@ -1,33 +1,33 @@
 {
-  "borrow: first": "189363",
-  "borrow: second action, same reserve": "169312",
-  "liquidationCall (receiveShares): full": "295052",
-  "liquidationCall (receiveShares): partial": "294770",
-  "liquidationCall: full": "304431",
-  "liquidationCall: partial": "304149",
-  "permitReserve + repay (multicall)": "164456",
-  "permitReserve + supply (multicall)": "146735",
-  "permitReserve + supply + enable collateral (multicall)": "161148",
-  "repay: full": "123772",
-  "repay: partial": "128742",
+  "borrow: first": "190151",
+  "borrow: second action, same reserve": "170100",
+  "liquidationCall (receiveShares): full": "302258",
+  "liquidationCall (receiveShares): partial": "301676",
+  "liquidationCall: full": "319683",
+  "liquidationCall: partial": "319101",
+  "permitReserve + repay (multicall)": "164598",
+  "permitReserve + supply (multicall)": "146729",
+  "permitReserve + supply + enable collateral (multicall)": "161142",
+  "repay: full": "123914",
+  "repay: partial": "128872",
   "setUserPositionManagersWithSig: disable": "47039",
   "setUserPositionManagersWithSig: enable": "68951",
-  "supply + enable collateral (multicall)": "141328",
-  "supply: 0 borrows, collateral disabled": "122803",
-  "supply: 0 borrows, collateral enabled": "105774",
-  "supply: second action, same reserve": "105703",
-  "updateUserDynamicConfig: 1 collateral": "74548",
-  "updateUserDynamicConfig: 2 collaterals": "89453",
-  "updateUserRiskPremium: 1 borrow": "94781",
-  "updateUserRiskPremium: 2 borrows": "103916",
+  "supply + enable collateral (multicall)": "141322",
+  "supply: 0 borrows, collateral disabled": "122797",
+  "supply: 0 borrows, collateral enabled": "105768",
+  "supply: second action, same reserve": "105697",
+  "updateUserDynamicConfig: 1 collateral": "74536",
+  "updateUserDynamicConfig: 2 collaterals": "89404",
+  "updateUserRiskPremium: 1 borrow": "95584",
+  "updateUserRiskPremium: 2 borrows": "105233",
   "usingAsCollateral: 0 borrows, enable": "59578",
-  "usingAsCollateral: 1 borrow, disable": "104896",
+  "usingAsCollateral: 1 borrow, disable": "105702",
   "usingAsCollateral: 1 borrow, enable": "42466",
-  "usingAsCollateral: 2 borrows, disable": "125992",
+  "usingAsCollateral: 2 borrows, disable": "127220",
   "usingAsCollateral: 2 borrows, enable": "42478",
-  "withdraw: 0 borrows, full": "127753",
-  "withdraw: 0 borrows, partial": "132439",
-  "withdraw: 1 borrow, partial": "158821",
-  "withdraw: 2 borrows, partial": "172927",
-  "withdraw: non collateral": "105709"
+  "withdraw: 0 borrows, full": "127735",
+  "withdraw: 0 borrows, partial": "132550",
+  "withdraw: 1 borrow, partial": "159621",
+  "withdraw: 2 borrows, partial": "174148",
+  "withdraw: non collateral": "105691"
 }

snapshots/Spoke.Operations.json

@@ -1,33 +1,33 @@
 {
-  "borrow: first": "258289",
-  "borrow: second action, same reserve": "201238",
-  "liquidationCall (receiveShares): full": "327083",
-  "liquidationCall (receiveShares): partial": "326801",
-  "liquidationCall: full": "336462",
-  "liquidationCall: partial": "336180",
-  "permitReserve + repay (multicall)": "161948",
-  "permitReserve + supply (multicall)": "146735",
-  "permitReserve + supply + enable collateral (multicall)": "161148",
-  "repay: full": "117851",
-  "repay: partial": "137221",
+  "borrow: first": "259059",
+  "borrow: second action, same reserve": "202008",
+  "liquidationCall (receiveShares): full": "334275",
+  "liquidationCall (receiveShares): partial": "333693",
+  "liquidationCall: full": "351700",
+  "liquidationCall: partial": "351118",
+  "permitReserve + repay (multicall)": "162062",
+  "permitReserve + supply (multicall)": "146729",
+  "permitReserve + supply + enable collateral (multicall)": "161142",
+  "repay: full": "117993",
+  "repay: partial": "137351",
   "setUserPositionManagersWithSig: disable": "47039",
   "setUserPositionManagersWithSig: enable": "68951",
-  "supply + enable collateral (multicall)": "141328",
-  "supply: 0 borrows, collateral disabled": "122803",
-  "supply: 0 borrows, collateral enabled": "105774",
-  "supply: second action, same reserve": "105703",
-  "updateUserDynamicConfig: 1 collateral": "74548",
-  "updateUserDynamicConfig: 2 collaterals": "89453",
-  "updateUserRiskPremium: 1 borrow": "148128",
-  "updateUserRiskPremium: 2 borrows": "197859",
+  "supply + enable collateral (multicall)": "141322",
+  "supply: 0 borrows, collateral disabled": "122797",
+  "supply: 0 borrows, collateral enabled": "105768",
+  "supply: second action, same reserve": "105697",
+  "updateUserDynamicConfig: 1 collateral": "74536",
+  "updateUserDynamicConfig: 2 collaterals": "89404",
+  "updateUserRiskPremium: 1 borrow": "148916",
+  "updateUserRiskPremium: 2 borrows": "199144",
   "usingAsCollateral: 0 borrows, enable": "59578",
-  "usingAsCollateral: 1 borrow, disable": "158243",
+  "usingAsCollateral: 1 borrow, disable": "159031",
   "usingAsCollateral: 1 borrow, enable": "42466",
-  "usingAsCollateral: 2 borrows, disable": "227935",
+  "usingAsCollateral: 2 borrows, disable": "229127",
   "usingAsCollateral: 2 borrows, enable": "42478",
-  "withdraw: 0 borrows, full": "127753",
-  "withdraw: 0 borrows, partial": "132439",
-  "withdraw: 1 borrow, partial": "209666",
-  "withdraw: 2 borrows, partial": "255403",
-  "withdraw: non collateral": "105709"
+  "withdraw: 0 borrows, full": "127735",
+  "withdraw: 0 borrows, partial": "132550",
+  "withdraw: 1 borrow, partial": "210448",
+  "withdraw: 2 borrows, partial": "256590",
+  "withdraw: non collateral": "105691"
 }

src/hub/Hub.sol

@@ -11,7 +11,7 @@ import {PercentageMath} from 'src/libraries/math/PercentageMath.sol';
 import {WadRayMath} from 'src/libraries/math/WadRayMath.sol';
 import {AssetLogic} from 'src/hub/libraries/AssetLogic.sol';
 import {SharesMath} from 'src/hub/libraries/SharesMath.sol';
-import {Premium} from 'src/hub/libraries/Premium.sol';
+import {IOU} from 'src/hub/libraries/IOU.sol';
 import {IBasicInterestRateStrategy} from 'src/hub/interfaces/IBasicInterestRateStrategy.sol';
 import {IHubBase, IHub} from 'src/hub/interfaces/IHub.sol';
 
@@ -306,15 +306,23 @@ contract Hub is IHub, AccessManaged {
     spoke.drawnShares -= drawnShares;
     _applyPremiumDelta(asset, spoke, premiumDelta);
 
-    uint256 premiumAmount = premiumDelta.restoredPremiumRay.fromRayUp();
-    uint256 liquidity = asset.liquidity + drawnAmount + premiumAmount;
+    uint256 restoredRay = IOU.calculateDrawnRay(drawnShares, asset.drawnIndex) +
+      premiumDelta.restoredPremiumRay;
+    uint256 liquidity = asset.liquidity + restoredRay.fromRayUp();
     uint256 balance = IERC20(asset.underlying).balanceOf(address(this));
     require(balance >= liquidity, InsufficientTransferred(liquidity.uncheckedSub(balance)));
     asset.liquidity = liquidity.toUint120();
 
     asset.updateDrawnRate(assetId);
 
-    emit Restore(assetId, msg.sender, drawnShares, premiumDelta, drawnAmount, premiumAmount);
+    emit Restore(
+      assetId,
+      msg.sender,
+      drawnShares,
+      premiumDelta,
+      drawnAmount,
+      premiumDelta.restoredPremiumRay.fromRayUp()
+    );
 
     return drawnShares;
   }
@@ -336,7 +344,7 @@ contract Hub is IHub, AccessManaged {
     spoke.drawnShares -= drawnShares;
     _applyPremiumDelta(asset, spoke, premiumDelta);
 
-    uint256 deficitAmountRay = uint256(drawnShares) * asset.drawnIndex +
+    uint256 deficitAmountRay = IOU.calculateDrawnRay(drawnShares, asset.drawnIndex) +
       premiumDelta.restoredPremiumRay;
     asset.deficitRay += deficitAmountRay.toUint200();
     spoke.deficitRay += deficitAmountRay.toUint200();
@@ -541,20 +549,32 @@ contract Hub is IHub, AccessManaged {
   function getAssetOwed(uint256 assetId) external view returns (uint256, uint256) {
     Asset storage asset = _assets[assetId];
     uint256 drawnIndex = asset.getDrawnIndex();
-    return (asset.drawn(drawnIndex), asset.premium(drawnIndex));
+    uint256 premium = IOU
+      .calculatePremiumRay(asset.premiumShares, asset.premiumOffsetRay, drawnIndex)
+      .fromRayUp();
+    return (asset.getAssetDrawn(drawnIndex), premium);
   }
 
   /// @inheritdoc IHubBase
   function getAssetTotalOwed(uint256 assetId) external view returns (uint256) {
     Asset storage asset = _assets[assetId];
-    return asset.totalOwed(asset.getDrawnIndex());
+    return
+      IOU
+        .calculateTotalOwedRay({
+          drawnShares: asset.drawnShares,
+          premiumShares: asset.premiumShares,
+          premiumOffsetRay: asset.premiumOffsetRay,
+          deficitRay: asset.deficitRay,
+          drawnIndex: asset.getDrawnIndex()
+        })
+        .fromRayUp();
   }
 
   /// @inheritdoc IHubBase
   function getAssetPremiumRay(uint256 assetId) external view returns (uint256) {
     Asset storage asset = _assets[assetId];
     return
-      Premium.calculatePremiumRay({
+      IOU.calculatePremiumRay({
         premiumShares: asset.premiumShares,
         premiumOffsetRay: asset.premiumOffsetRay,
         drawnIndex: asset.getDrawnIndex()
@@ -634,14 +654,28 @@ contract Hub is IHub, AccessManaged {
   function getSpokeOwed(uint256 assetId, address spoke) external view returns (uint256, uint256) {
     Asset storage asset = _assets[assetId];
     SpokeData storage spokeData = _spokes[assetId][spoke];
-    return (_getSpokeDrawn(asset, spokeData), _getSpokePremium(asset, spokeData));
+    uint256 drawnIndex = asset.getDrawnIndex();
+    uint256 drawn = IOU.calculateDrawnRay(spokeData.drawnShares, drawnIndex).fromRayUp();
+    uint256 premium = IOU
+      .calculatePremiumRay(spokeData.premiumShares, spokeData.premiumOffsetRay, drawnIndex)
+      .fromRayUp();
+    return (drawn, premium);
   }
 
   /// @inheritdoc IHubBase
   function getSpokeTotalOwed(uint256 assetId, address spoke) external view returns (uint256) {
     Asset storage asset = _assets[assetId];
     SpokeData storage spokeData = _spokes[assetId][spoke];
-    return _getSpokeDrawn(asset, spokeData) + _getSpokePremium(asset, spokeData);
+    return
+      IOU
+        .calculateTotalOwedRay({
+          drawnShares: spokeData.drawnShares,
+          premiumShares: spokeData.premiumShares,
+          premiumOffsetRay: spokeData.premiumOffsetRay,
+          deficitRay: spokeData.deficitRay,
+          drawnIndex: asset.getDrawnIndex()
+        })
+        .fromRayUp();
   }
 
   /// @inheritdoc IHubBase
@@ -798,20 +832,11 @@ contract Hub is IHub, AccessManaged {
     return shares;
   }
 
-  /// @dev Returns the spoke's drawn amount for a specified asset.
   function _getSpokeDrawn(
     Asset storage asset,
     SpokeData storage spoke
   ) internal view returns (uint256) {
-    return asset.toDrawnAssetsUp(spoke.drawnShares);
-  }
-
-  /// @dev Returns the spoke's premium amount for a specified asset.
-  function _getSpokePremium(
-    Asset storage asset,
-    SpokeData storage spoke
-  ) internal view returns (uint256) {
-    return _getSpokePremiumRay(asset, spoke).fromRayUp();
+    return IOU.calculateDrawnRay(spoke.drawnShares, asset.getDrawnIndex()).fromRayUp();
   }
 
   /// @dev Returns the spoke's premium amount with full precision for a specified asset.
@@ -820,7 +845,7 @@ contract Hub is IHub, AccessManaged {
     SpokeData storage spoke
   ) internal view returns (uint256) {
     return
-      Premium.calculatePremiumRay({
+      IOU.calculatePremiumRay({
         premiumShares: spoke.premiumShares,
         premiumOffsetRay: spoke.premiumOffsetRay,
         drawnIndex: asset.getDrawnIndex()
@@ -864,11 +889,18 @@ contract Hub is IHub, AccessManaged {
     require(spoke.active, SpokeNotActive());
     require(!spoke.halted, SpokeHalted());
     uint256 drawCap = spoke.drawCap;
-    uint256 owed = _getSpokeDrawn(asset, spoke) + _getSpokePremium(asset, spoke);
+    uint256 owed = IOU
+      .calculateTotalOwedRay({
+        drawnShares: spoke.drawnShares,
+        premiumShares: spoke.premiumShares,
+        premiumOffsetRay: spoke.premiumOffsetRay,
+        deficitRay: spoke.deficitRay,
+        drawnIndex: asset.getDrawnIndex()
+      })
+      .fromRayUp();
     require(
       drawCap == MAX_ALLOWED_SPOKE_CAP ||
-        drawCap * MathUtils.uncheckedExp(10, asset.decimals) >=
-          owed + amount + uint256(spoke.deficitRay).fromRayUp(),
+        drawCap * MathUtils.uncheckedExp(10, asset.decimals) >= owed + amount,
       DrawCapExceeded(drawCap)
     );
   }
@@ -952,7 +984,7 @@ contract Hub is IHub, AccessManaged {
     int256 premiumOffsetRay,
     PremiumDelta calldata premiumDelta
   ) internal pure returns (uint120, int200) {
-    uint256 premiumRayBefore = Premium.calculatePremiumRay({
+    uint256 premiumRayBefore = IOU.calculatePremiumRay({
       premiumShares: premiumShares,
       premiumOffsetRay: premiumOffsetRay,
       drawnIndex: drawnIndex
@@ -961,7 +993,7 @@ contract Hub is IHub, AccessManaged {
     uint256 newPremiumShares = premiumShares.add(premiumDelta.sharesDelta);
     int256 newPremiumOffsetRay = premiumOffsetRay + premiumDelta.offsetRayDelta;
 
-    uint256 premiumRayAfter = Premium.calculatePremiumRay({
+    uint256 premiumRayAfter = IOU.calculatePremiumRay({
       premiumShares: newPremiumShares,
       premiumOffsetRay: newPremiumOffsetRay,
       drawnIndex: drawnIndex