refactor: address PR comments

contracts/domain/BosonErrors.sol

@@ -377,7 +377,7 @@ interface BosonErrors {
     // Price does not cover the cancellation penalty
     error PriceDoesNotCoverPenalty();
 
-    //Fee Table related
-    // Exchange token should be different than $BOSON when requesting feePercentage
-    error InvalidExchangeToken();
+    // Fee Table related
+    // Thrown if asset is not supported in feeTable feature.
+    error FeeTableAssetNotSupported();
 }

contracts/interfaces/handlers/IBosonConfigHandler.sol

@@ -10,7 +10,7 @@ import { IBosonConfigEvents } from "../events/IBosonConfigEvents.sol";
  *
  * @notice Handles management of configuration within the protocol.
  *
- * The ERC-165 identifier for this interface is: 0x13fd085d
+ * The ERC-165 identifier for this interface is: 0xe9aa49b6
  */
 interface IBosonConfigHandler is IBosonConfigEvents, BosonErrors {
     /**
@@ -149,6 +149,17 @@ interface IBosonConfigHandler is IBosonConfigEvents, BosonErrors {
         uint256[] calldata _feePercentages
     ) external;
 
+    /**
+     * @notice Gets the current fee table for a given token.
+     *
+     * @param _tokenAddress - the address of the token
+     * @return priceRanges - array of token price ranges
+     * @return feePercentages - array of fee percentages corresponding to each price range
+     */
+    function getProtocolFeeTable(
+        address _tokenAddress
+    ) external view returns (uint256[] memory priceRanges, uint256[] memory feePercentages);
+
     /**
      * @notice Gets the default protocol fee percentage.
      *

contracts/protocol/bases/ProtocolBase.sol

@@ -712,7 +712,7 @@ abstract contract ProtocolBase is PausableBase, ReentrancyGuardBase, BosonErrors
      * @return feePercentage - the protocol fee percentage based on token price (using protocol fee table)
      */
     function _getFeePercentage(address _exchangeToken, uint256 _price) internal view returns (uint256 feePercentage) {
-        if (_exchangeToken == protocolAddresses().token) revert InvalidExchangeToken();
+        if (_exchangeToken == protocolAddresses().token) revert FeeTableAssetNotSupported();
 
         ProtocolLib.ProtocolFees storage fees = protocolFees();
         uint256[] storage priceRanges = fees.tokenPriceRanges[_exchangeToken];
@@ -721,7 +721,7 @@ abstract contract ProtocolBase is PausableBase, ReentrancyGuardBase, BosonErrors
         // If the token has a custom fee table, find the appropriate percentage
         uint256 priceRangesLength = priceRanges.length;
         if (priceRangesLength > 0) {
-            for (uint256 i; i < priceRangesLength; ++i) {
+            for (uint256 i; i < priceRangesLength - 1; ++i) {
                 if (_price <= priceRanges[i]) {
                     // Return the fee percentage for the matching price range
                     return feePercentages[i];

contracts/protocol/facets/ConfigHandlerFacet.sol

@@ -233,6 +233,7 @@ contract ConfigHandlerFacet is IBosonConfigHandler, ProtocolBase {
      * @notice Sets the feeTable for a specific token given price ranges and fee tiers for
      * the corresponding price ranges.
      *
+     * Reverts if token is $BOSON.
      * Reverts if the number of fee percentages does not match the number of price ranges.
      * Reverts if the price ranges are not in ascending order.
      * Reverts if any of the fee percentages value is above 100%.
@@ -248,6 +249,7 @@ contract ConfigHandlerFacet is IBosonConfigHandler, ProtocolBase {
         uint256[] calldata _priceRanges,
         uint256[] calldata _feePercentages
     ) external override onlyRole(ADMIN) nonReentrant {
+        if (_tokenAddress == protocolAddresses().token) revert FeeTableAssetNotSupported();
         if (_priceRanges.length != _feePercentages.length) revert ArrayLengthMismatch();
         // Clear existing price ranges and percentage tiers
         delete protocolFees().tokenPriceRanges[_tokenAddress];
@@ -260,6 +262,24 @@ contract ConfigHandlerFacet is IBosonConfigHandler, ProtocolBase {
         emit FeeTableUpdated(_tokenAddress, _priceRanges, _feePercentages, msgSender());
     }
 
+    /**
+     * @notice Gets the current fee table for a given token.
+     *
+     * @dev This funciton is used to check price ranges config. If you need to apply percentage based on
+     *      _exchangeToken and offerPrice, use getProtocolFeePercentage(address,uint256)
+     *
+     * @param _tokenAddress - the address of the token
+     * @return priceRanges - array of token price ranges
+     * @return feePercentages - array of fee percentages corresponding to each price range
+     */
+    function getProtocolFeeTable(
+        address _tokenAddress
+    ) external view returns (uint256[] memory priceRanges, uint256[] memory feePercentages) {
+        ProtocolLib.ProtocolFees storage fees = protocolFees();
+        priceRanges = fees.tokenPriceRanges[_tokenAddress];
+        feePercentages = fees.tokenFeePercentages[_tokenAddress];
+    }
+
     /**
      * @notice Gets the default protocol fee percentage.
      *
@@ -638,7 +658,7 @@ contract ConfigHandlerFacet is IBosonConfigHandler, ProtocolBase {
      */
     function setTokenPriceRanges(address _tokenAddress, uint256[] calldata _priceRanges) internal {
         for (uint256 i = 1; i < _priceRanges.length; ++i) {
-            if (_priceRanges[i] < _priceRanges[i - 1]) revert NonAscendingOrder();
+            if (_priceRanges[i] <= _priceRanges[i - 1]) revert NonAscendingOrder();
         }
         protocolFees().tokenPriceRanges[_tokenAddress] = _priceRanges;
     }

scripts/config/revert-reasons.js

@@ -237,5 +237,5 @@ exports.RevertReasons = {
   PRICE_DOES_NOT_COVER_PENALTY: "PriceDoesNotCoverPenalty",
 
   //Fee Table related
-  INVALID_EXCHANGE_TOKEN: "InvalidExchangeToken",
+  FEE_TABLE_ASSET_NOT_SUPOPRTED: "FeeTableAssetNotSupported",
 };

test/protocol/ConfigHandlerTest.js

@@ -1013,6 +1013,13 @@ describe("IBosonConfigHandler", function () {
               configHandler.connect(rando).setProtocolFeeTable(usdcAddress, feePriceRanges, feePercentages)
             ).to.revertedWithCustomError(bosonErrors, RevertReasons.ACCESS_DENIED);
           });
+          it("should revert if _tokenAddress is the BOSON token", async function () {
+            await expect(
+              configHandler
+                .connect(deployer)
+                .setProtocolFeeTable(await token.getAddress(), feePriceRanges, feePercentages)
+            ).to.be.revertedWithCustomError(bosonErrors, RevertReasons.FEE_TABLE_ASSET_NOT_SUPOPRTED);
+          });
           it("price ranges count different from fee percents", async function () {
             const newPriceRanges = [...feePriceRanges, parseUnits("10", "ether").toString()];
             await expect(
@@ -1042,7 +1049,7 @@ describe("IBosonConfigHandler", function () {
             const randomPrice = 10000;
             await expect(
               configHandler.connect(rando).getProtocolFeePercentage(await token.getAddress(), randomPrice)
-            ).to.revertedWithCustomError(bosonErrors, RevertReasons.INVALID_EXCHANGE_TOKEN);
+            ).to.revertedWithCustomError(bosonErrors, RevertReasons.FEE_TABLE_ASSET_NOT_SUPOPRTED);
           });
         });
       });
@@ -1125,6 +1132,24 @@ describe("IBosonConfigHandler", function () {
           minDisputePeriod,
           "Invalid min dispute period"
         );
+        it("Should return the correct fee table for a token", async function () {
+          const feePriceRanges = [
+            parseUnits("1", "ether").toString(),
+            parseUnits("2", "ether").toString(),
+            parseUnits("5", "ether").toString(),
+          ];
+          const feePercentages = [500, 1000, 2000]; // 5%, 10%, 20%
+
+          await configHandler.connect(deployer).setProtocolFeeTable(usdc.address, feePriceRanges, feePercentages);
+
+          const [retrievedRanges, retrievedPercentages] = await configHandler.getProtocolFeeTable(usdc.address);
+
+          expect(retrievedRanges.map((r) => r.toString())).to.deep.equal(feePriceRanges, "Incorrect price ranges");
+          expect(retrievedPercentages.map((p) => p.toNumber())).to.deep.equal(
+            feePercentages,
+            "Incorrect fee percentages"
+          );
+        });
       });
     });
   });