From 0a33d4aed571120f34e7608a171e144df159d011 Mon Sep 17 00:00:00 2001
From: Qiwen Li <qiwen_li@brown.edu>
Date: Thu, 14 Dec 2023 18:10:59 -0500
Subject: [PATCH] [OSCI][Fix][Discover]Prevent Adding Timefield to the Side Nav
 Selected Fields on Column Removal (#5537)

* added in a filter for columns before rendering the panel, remove timeField if it was not previously chosen.
* fix issue 5538 too
---------

Signed-off-by: qiwen li <qiwen_li@brown.edu>
Signed-off-by: Qiwen Li <qiwen_li@brown.edu>
---
 CHANGELOG.md                                  |  1 +
 .../view_components/panel/index.tsx           | 24 ++++++++++++++++++-
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 87aa8c065ea..606355e8458 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -36,6 +36,7 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 - [BUG] Fix filtering issue in data source selector ([5484](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5484))
 - [BUG][Data] Support for custom filters with heterogeneous data fields ([5577](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5577))
 - [BUG][Data] Fix empty suggestion history when querying in search bar [#5349](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5349)
+- [BUG][Discover] Fix what is displayed in `selected fields` when removing columns from canvas [#5537](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/5537)
 
 ### 🚞 Infrastructure
 
diff --git a/src/plugins/discover/public/application/view_components/panel/index.tsx b/src/plugins/discover/public/application/view_components/panel/index.tsx
index bbf5331fb16..6b4cd2a87c9 100644
--- a/src/plugins/discover/public/application/view_components/panel/index.tsx
+++ b/src/plugins/discover/public/application/view_components/panel/index.tsx
@@ -3,12 +3,13 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-import React, { useCallback, useEffect, useState } from 'react';
+import React, { useCallback, useEffect, useRef, useState } from 'react';
 import { ViewProps } from '../../../../../data_explorer/public';
 import {
   addColumn,
   removeColumn,
   reorderColumn,
+  setColumns,
   useDispatch,
   useSelector,
 } from '../../utils/state_management';
@@ -19,6 +20,7 @@ import { IndexPatternField, opensearchFilters } from '../../../../../data/public
 import { useOpenSearchDashboards } from '../../../../../opensearch_dashboards_react/public';
 import { DiscoverViewServices } from '../../../build_services';
 import { popularizeField } from '../../helpers/popularize_field';
+import { buildColumns } from '../../utils/columns';
 
 // eslint-disable-next-line import/no-default-export
 export default function DiscoverPanel(props: ViewProps) {
@@ -36,7 +38,27 @@ export default function DiscoverPanel(props: ViewProps) {
   const { columns } = useSelector((state) => ({
     columns: state.discover.columns,
   }));
+
+  const prevColumns = useRef(columns);
   const dispatch = useDispatch();
+  useEffect(() => {
+    const timeFieldname = indexPattern?.timeFieldName;
+
+    if (columns !== prevColumns.current) {
+      let updatedColumns = buildColumns(columns);
+      if (
+        timeFieldname &&
+        !prevColumns.current.includes(timeFieldname) &&
+        columns.includes(timeFieldname)
+      ) {
+        // Remove timeFieldname from columns if previously chosen columns does not include time field
+        updatedColumns = columns.filter((column) => column !== timeFieldname);
+      }
+      // Update the ref with the new columns
+      dispatch(setColumns({ columns: updatedColumns }));
+      prevColumns.current = columns;
+    }
+  }, [columns, dispatch, indexPattern?.timeFieldName]);
 
   useEffect(() => {
     const subscription = data$.subscribe((next) => {