make show timeline more generic so we can re-use if need it

Author: XavierM

x-pack/legacy/plugins/siem/public/pages/home/index.tsx

@@ -21,6 +21,7 @@ import { AutoSaveWarningMsg } from '../../components/timeline/auto_save_warning'
 import { UseUrlState } from '../../components/url_state';
 import { WithSource, indicesExistOrDataTemporarilyUnavailable } from '../../containers/source';
 import { SpyRoute } from '../../utils/route/spy_routes';
+import { useShowTimeline } from '../../utils/timeline/use_show_timeline';
 import { NotFoundPage } from '../404';
 import { DetectionEngineContainer } from '../detection_engine';
 import { HostsContainer } from '../hosts';
@@ -68,7 +69,7 @@ export const HomePage: React.FC = () => {
     windowHeight,
   });
 
-  const currentLocation = useLocation();
+  const [showTimeline] = useShowTimeline();
 
   return (
     <WrappedByAutoSizer data-test-subj="wrapped-by-auto-sizer" ref={measureRef}>
@@ -79,7 +80,7 @@ export const HomePage: React.FC = () => {
           {({ browserFields, indexPattern, indicesExist }) => (
             <DragDropContextWrapper browserFields={browserFields}>
               <UseUrlState indexPattern={indexPattern} navTabs={navTabs} />
-              {indicesExistOrDataTemporarilyUnavailable(indicesExist) && (
+              {indicesExistOrDataTemporarilyUnavailable(indicesExist) && showTimeline && (
                 <>
                   <AutoSaveWarningMsg />
                   <Flyout

x-pack/legacy/plugins/siem/public/utils/timeline/use_show_timeline.tsx

@@ -0,0 +1,31 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+import { useLocation } from 'react-router-dom';
+
+import { useState, useEffect } from 'react';
+import { SiemPageName } from '../../pages/home/types';
+
+const hideTimelineForRoutes = [`/${SiemPageName.case}/configure`];
+
+export const useShowTimeline = () => {
+  const currentLocation = useLocation();
+  const [showTimeline, setShowTimeline] = useState(
+    !hideTimelineForRoutes.includes(currentLocation.pathname)
+  );
+
+  useEffect(() => {
+    if (hideTimelineForRoutes.includes(currentLocation.pathname)) {
+      if (showTimeline) {
+        setShowTimeline(false);
+      }
+    } else if (!showTimeline) {
+      setShowTimeline(true);
+    }
+  }, [currentLocation.pathname]);
+
+  return [showTimeline];
+};