ui: showSignInDialog if react when not loggedin

packages/ui-default/components/discussion/comments.page.tsx

@@ -6,6 +6,7 @@ import { Popover } from '@blueprintjs/core';
 import { AutoloadPage } from 'vj/misc/Page';
 import CommentBox from 'vj/components/discussion/CommentBox';
 import { ConfirmDialog } from 'vj/components/dialog';
+import Notification from 'vj/components/notification';
 
 import delay from 'vj/utils/delay';
 import { slideDown, slideUp } from 'vj/utils/slide';
@@ -254,10 +255,15 @@ const commentsPage = new AutoloadPage('commentsPage', () => {
   $(document).on('click', '[data-op="delete"][data-type="comment"]', onCommentClickDeleteComment);
   $(document).on('click', '[data-op="delete"][data-type="reply"]', onCommentClickDeleteReply);
 
+  const canUseReaction = $('[data-op="react"]').length > 0;
   $('[data-op="react"]').each((i, e) => {
     ReactDOM.render(<Reaction payload={$(e).data('form')} ele={$(e).closest('.media__body').find('.reactions')} />, e);
   });
   $(document).on('click', '.reaction', async (e) => {
+    if (!canUseReaction) {
+      (window as any).showSignInDialog();
+      return;
+    }
     const target = $(e.currentTarget);
     const res = await request.post('', {
       operation: 'reaction',