chat history and other stuffs, light commands replay fixes

webui/src/hooks/useChatMessageHistoryNavigation.js

@@ -0,0 +1,52 @@
+// Chat Message History Navigation
+// Purpose: Gives each chat input Bash-style traversal over the shared persisted send history.
+// Scope: Owns only draft/navigation state; it does not register global keys or interact with rover controls.
+import { useCallback, useRef } from 'react';
+import { useChatHistory } from '../context/ChatContext.jsx';
+
+export default function useChatMessageHistoryNavigation() {
+  const { messageHistory } = useChatHistory();
+  const historyIndexRef = useRef(null);
+  const preservedDraftRef = useRef('');
+
+  const resetHistoryNavigation = useCallback(() => {
+    // Manual edits and successful sends begin a new navigation session. The
+    // current input value remains owned by the composer and is not changed here.
+    historyIndexRef.current = null;
+    preservedDraftRef.current = '';
+  }, []);
+
+  const navigateHistory = useCallback(
+    (direction, currentDraft) => {
+      if (!messageHistory.length) return null;
+
+      if (direction === 'previous') {
+        if (historyIndexRef.current === null) {
+          // Save the in-progress draft exactly once so ArrowDown can restore it
+          // after the user reaches the newest edge of history, like a shell.
+          preservedDraftRef.current = currentDraft;
+          historyIndexRef.current = messageHistory.length - 1;
+        } else {
+          historyIndexRef.current = Math.max(0, historyIndexRef.current - 1);
+        }
+        return messageHistory[historyIndexRef.current];
+      }
+
+      if (direction === 'next' && historyIndexRef.current !== null) {
+        if (historyIndexRef.current < messageHistory.length - 1) {
+          historyIndexRef.current += 1;
+          return messageHistory[historyIndexRef.current];
+        }
+
+        const preservedDraft = preservedDraftRef.current;
+        resetHistoryNavigation();
+        return preservedDraft;
+      }
+
+      return null;
+    },
+    [messageHistory, resetHistoryNavigation],
+  );
+
+  return { navigateHistory, resetHistoryNavigation };
+}