fix: delivery recording bug

contracts/BalanceTrackerFixedPriceBase.sol

@@ -88,8 +88,8 @@ abstract contract BalanceTrackerFixedPriceBase {
 
     // Check and record delivery rate
     function checkAndRecordDeliveryRate(
-        address mech,
         address requester,
+        uint256 maxDeliveryRate,
         bytes memory
     ) external payable {
         // Reentrancy guard
@@ -109,9 +109,6 @@ abstract contract BalanceTrackerFixedPriceBase {
         // Get account balance
         uint256 balance = mapRequesterBalances[requester] + initAmount;
 
-        // Get mech max delivery rate
-        uint256 maxDeliveryRate = IMech(mech).maxDeliveryRate();
-
         // Check the request delivery rate for a fixed price
         if (balance < maxDeliveryRate) {
             // Get balance difference
@@ -150,12 +147,14 @@ abstract contract BalanceTrackerFixedPriceBase {
             revert ZeroValue();
         }
 
+        // Check for delivery rate difference
         uint256 rateDiff;
         if (maxDeliveryRate > actualDeliveryRate) {
             // Return back requester overpayment debit
             rateDiff = maxDeliveryRate - actualDeliveryRate;
             mapRequesterBalances[requester] += rateDiff;
         } else {
+            // Limit the rate by the max chosen one as that is what the requester agreed on
             actualDeliveryRate = maxDeliveryRate;
         }
 

contracts/MechMarketplace.sol

@@ -381,13 +381,6 @@ contract MechMarketplace is IErrorsMarketplace {
         // Get the request Id
         requestId = getRequestId(msg.sender, data, mapNonces[msg.sender]);
 
-        // Get balance tracker address
-        bytes32 mechPaymentType = IMech(priorityMech).paymentType();
-        address balanceTracker = mapPaymentTypeBalanceTrackers[mechPaymentType];
-
-        // Check and record mech delivery rate
-        IBalanceTracker(balanceTracker).checkAndRecordDeliveryRate{value: msg.value}(priorityMech, msg.sender, paymentData);
-
         // Update requester nonce
         mapNonces[msg.sender]++;
 
@@ -400,8 +393,16 @@ contract MechMarketplace is IErrorsMarketplace {
         mechDelivery.responseTimeout = responseTimeout + block.timestamp;
         // Record request account
         mechDelivery.requester = msg.sender;
-        // Record deliveryRate for request
-        mechDelivery.deliveryRate = msg.value;
+        // Record deliveryRate for request as priority mech max delivery rate
+        mechDelivery.deliveryRate = IMech(priorityMech).maxDeliveryRate();
+
+        // Get balance tracker address
+        bytes32 mechPaymentType = IMech(priorityMech).paymentType();
+        address balanceTracker = mapPaymentTypeBalanceTrackers[mechPaymentType];
+
+        // Check and record mech delivery rate
+        IBalanceTracker(balanceTracker).checkAndRecordDeliveryRate{value: msg.value}(msg.sender,
+            mechDelivery.deliveryRate, paymentData);
 
         // Increase mech requester karma
         IKarma(karma).changeRequesterMechKarma(msg.sender, priorityMech, 1);

contracts/integrations/nevermined/BalanceTrackerNvmSubscription.sol

@@ -88,19 +88,15 @@ contract BalanceTrackerNvmSubscription {
 
     // Check and record delivery rate
     function checkAndRecordDeliveryRate(
-        address mech,
         address requester,
-        uint256,
+        uint256 maxDeliveryRate,
         bytes memory
     ) external payable {
         // Check for marketplace access
         if (msg.sender != mechMarketplace) {
             revert MarketplaceOnly(msg.sender, mechMarketplace);
         }
 
-        // Get mech max delivery rate
-        uint256 maxDeliveryRate = IMech(mech).maxDeliveryRate();
-
         // Check that there is no incoming deposit
         if (msg.value > 0) {
             revert NoDepositAllowed(msg.value);

contracts/interfaces/IBalanceTracker.sol

@@ -5,7 +5,7 @@ pragma solidity ^0.8.28;
 interface IBalanceTracker {
     // Check and record delivery rate
     /// @param paymentData Additional payment-related request data, if applicable.
-    function checkAndRecordDeliveryRate(address mech, address requester, bytes memory paymentData) external payable;
+    function checkAndRecordDeliveryRate(address requester, uint256 maxDeliveryRate, bytes memory paymentData) external payable;
 
     /// @dev Finalizes mech delivery rate based on requested and actual ones.
     /// @param mech Delivery mech address.

test/MechFixedPriceNative.js

@@ -259,6 +259,46 @@ describe("MechFixedPriceNative", function () {
             expect(mechKarma).to.equal(1);
         });
 
+        it("Delivering a request by a priority mech with pre-paid logic", async function () {
+            // Get request Id
+            const requestId = await mechMarketplace.getRequestId(deployer.address, data, 0);
+
+            // Pre-pay the contract insufficient amount for posting a request
+            await deployer.sendTransaction({to: balanceTrackerFixedPriceNative.address, value: maxDeliveryRate - 1});
+
+            // Try to create request with insufficient pre-paid amount
+            await expect(
+                mechMarketplace.request(data, mechServiceId, requesterServiceId, minResponseTimeout, "0x")
+            ).to.be.revertedWithCustomError(balanceTrackerFixedPriceNative, "InsufficientBalance");
+
+            // Pre-pay the contract more for posting a request
+            await deployer.sendTransaction({to: balanceTrackerFixedPriceNative.address, value: maxDeliveryRate});
+
+            // Post a request
+            await mechMarketplace.request(data, mechServiceId, requesterServiceId, minResponseTimeout, "0x");
+
+            // Get the request status (requested priority)
+            status = await mechMarketplace.getRequestStatus(requestId);
+            expect(status).to.equal(1);
+
+            // Deliver a request
+            await priorityMech.deliverToMarketplace(requestId, data);
+
+            // Get the request status (delivered)
+            status = await mechMarketplace.getRequestStatus(requestId);
+            expect(status).to.equal(3);
+
+            // Try to deliver the same request again
+            await priorityMech.deliverToMarketplace(requestId, data);
+
+            // Check mech karma
+            let mechKarma = await karma.mapMechKarma(priorityMech.address);
+            expect(mechKarma).to.equal(1);
+            // Check requester mech karma
+            mechKarma = await karma.mapRequesterMechKarma(deployer.address, priorityMech.address);
+            expect(mechKarma).to.equal(1);
+        });
+
         it("Delivering a request by a different mech", async function () {
             // Take a snapshot of the current state of the blockchain
             const snapshot = await helpers.takeSnapshot();