Function EditMessageSelector

extensions/cli/src/ui/EditMessageSelector.tsx:19–292

({
  chatHistory,
  onEdit,
  onExit,
}: EditMessageSelectorProps)

}

export function EditMessageSelector({
  chatHistory,
  onEdit,
  onExit,
}: EditMessageSelectorProps) {
  // Filter to only show user messages
  const userMessages = useMemo(() => {
    return chatHistory
      .map((item, originalIndex) => ({ item, originalIndex }))
      .filter(({ item }) => item.message.role === "user");
  }, [chatHistory]);

  const [selectedIndex, setSelectedIndex] = useState(
    Math.max(0, userMessages.length - 1),
  );
  const [isEditing, setIsEditing] = useState(false);
  const [textBuffer] = useState(() => new TextBuffer());
  const [editText, setEditText] = useState("");
  const [cursorPosition, setCursorPosition] = useState(0);

  // Stable callback for TextBuffer state changes (e.g., paste finalization)
  const onStateChange = React.useCallback(() => {
    setEditText(textBuffer.text);
    setCursorPosition(textBuffer.cursor);
  }, [textBuffer]);

  // Set up callback for when TextBuffer state changes asynchronously
  React.useEffect(() => {
    textBuffer.setStateChangeCallback(onStateChange);

    return () => {
      // Clear any pending timers on unmount
      textBuffer.clear();
    };
  }, [textBuffer, onStateChange]);

  // Initialize edit text when selection changes
  React.useEffect(() => {
    if (!isEditing && userMessages[selectedIndex]) {
      const content =
        typeof userMessages[selectedIndex].item.message.content === "string"
          ? userMessages[selectedIndex].item.message.content
          : "";
      textBuffer.setText(content);
      setEditText(content);
      setCursorPosition(content.length);
    }
  }, [selectedIndex, isEditing, userMessages, textBuffer]);

  // Helper to get message content safely
  const getMessageContent = React.useCallback(
    (index: number): string => {
      return typeof userMessages[index]?.item.message.content === "string"
        ? userMessages[index].item.message.content
        : "";
    },
    [userMessages],
  );