avoid edge case with undo (#78)

src/components/chat/MessagesList.tsx

@@ -11,7 +11,7 @@ import { Loader2, RefreshCw, Undo } from "lucide-react";
 import { Button } from "@/components/ui/button";
 import { useVersions } from "@/hooks/useVersions";
 import { selectedAppIdAtom } from "@/atoms/appAtoms";
-import { showError } from "@/lib/toast";
+import { showError, showSuccess } from "@/lib/toast";
 import { IpcClient } from "@/ipc/ipc_client";
 import { chatMessagesAtom } from "@/atoms/chatAtoms";
 
@@ -26,10 +26,11 @@ export const MessagesList = forwardRef<HTMLDivElement, MessagesListProps>(
     const { versions, revertVersion } = useVersions(appId);
     const { streamMessage, isStreaming, error, setError } = useStreamChat();
     const { isAnyProviderSetup } = useSettings();
-    const selectedChatId = useAtomValue(selectedChatIdAtom);
+
     const setMessages = useSetAtom(chatMessagesAtom);
     const [isUndoLoading, setIsUndoLoading] = useState(false);
     const [isRetryLoading, setIsRetryLoading] = useState(false);
+    const [selectedChatId, setSelectedChatId] = useAtom(selectedChatIdAtom);
 
     return (
       <div className="flex-1 overflow-y-auto p-4" ref={ref}>
@@ -45,9 +46,10 @@ export const MessagesList = forwardRef<HTMLDivElement, MessagesListProps>(
             {!isAnyProviderSetup() && <SetupBanner />}
           </div>
         )}
-        {messages.length > 0 && !isStreaming && (
+        {messages.length > 3 && !isStreaming && (
           <div className="flex max-w-3xl mx-auto gap-2">
-            {messages[messages.length - 1].role === "assistant" && (
+            {messages[messages.length - 1].role === "assistant" &&
+              messages[messages.length - 1].commitHash && (
                 <Button
                   variant="outline"
                   size="sm"
@@ -70,22 +72,19 @@ export const MessagesList = forwardRef<HTMLDivElement, MessagesListProps>(
                         previousAssistantMessage?.role === "assistant" &&
                         previousAssistantMessage?.commitHash
                       ) {
-                      console.debug("Reverting to previous assistant version");
+                        console.debug(
+                          "Reverting to previous assistant version"
+                        );
                         await revertVersion({
                           versionId: previousAssistantMessage.commitHash,
                         });
-                    } else {
-                      // Revert to the previous version
-                      await revertVersion({
-                        versionId: versions[1].oid,
-                      });
-                    }
                         if (selectedChatId) {
                           const chat = await IpcClient.getInstance().getChat(
                             selectedChatId
                           );
                           setMessages(chat.messages);
                         }
+                      }
                     } catch (error) {
                       console.error("Error during undo operation:", error);
                       showError("Failed to undo changes");
@@ -138,10 +137,9 @@ export const MessagesList = forwardRef<HTMLDivElement, MessagesListProps>(
                       });
                       reverted = true;
                     } else {
-                      console.debug("Reverting to previous version");
-                      await revertVersion({
-                        versionId: versions[1].oid,
-                      });
+                      showSuccess(
+                        "You will need to manually revert to an earlier revision"
+                      );
                     }
                   }