From 878ba134e96245b038a9765148ad48a36bb2aa4b Mon Sep 17 00:00:00 2001
From: Maxim Palenov <maxim.palenov@elastic.co>
Date: Sat, 28 Sep 2024 00:07:12 +0300
Subject: [PATCH] [Security Solution] Integrate state and components for
 Prebuilt Rule Update Workflow (#193531)

**Epic:** https://github.com/elastic/kibana/issues/174168
**Addresses:** https://github.com/elastic/kibana/issues/171520

## Summary

This PR introduces a new `Update` tab allowing users to resolve rule upgrade conflicts. It's a result of combination of read-only components implemented in https://github.com/elastic/kibana/pull/193261 and rule upgrade state implemented in https://github.com/elastic/kibana/pull/191721.

## Details

The goal of this PR is to provide intermediate integration between rule upgrade state ([PR](https://github.com/elastic/kibana/pull/191721)) and components displaying the diff and read-only state ([PR](https://github.com/elastic/kibana/pull/193261)). It will facilitate further development of rule field editable components and streamline rule upgrade functionality developing.

## How to test?

The functionality is hidden under `prebuiltRulesCustomizationEnabled` feature flag. Add the following to your Kibana config

```yaml
xpack.securitySolution.enableExperimental:
  - prebuiltRulesCustomizationEnabled
```

When the above feature flag enabled the new `Update` tab is displayed instead of the old one.

## Screenshots

Suggested components design
![image](https://github.com/user-attachments/assets/b5aaf571-286a-4595-9bd4-fdaf9a423b03)

New `Update` tab
<img width="1718" alt="image" src="https://github.com/user-attachments/assets/28aa6bb3-f805-4109-a808-d67e58c7c5b8">
---
 .../components/split_accordion/index.ts       |  8 ++
 .../split_accordion/split_accordion.tsx       | 47 ++++++++++
 .../diff_components/field_diff.tsx            | 20 +++--
 .../rule_details/diff_components/index.ts     |  1 -
 .../diff_components/panel_wrapper.tsx         | 45 ----------
 .../comparison_side/comparison_side.tsx       | 15 ++--
 .../three_way_diff/comparison_side/utils.ts   |  2 +-
 .../field_upgrade_conflicts_resolver.tsx      | 67 +++++++++++++++
 ...ield_upgrade_conflicts_resolver_header.tsx | 25 ++++++
 .../rule_upgrade_conflicts_resolver.tsx       | 40 +++++++++
 .../components/rule_upgrade_info_bar.tsx      | 47 ++++++++++
 .../three_way_diff/components/side_header.tsx | 29 +++++++
 .../components/translations.tsx               | 62 ++++++++++++++
 .../three_way_diff/final_side/final_side.tsx  | 35 ++++++++
 .../final_side/final_side_help_info.tsx       | 43 ++++++++++
 .../three_way_diff/final_side/translations.ts | 15 ++++
 .../rule_upgrade_conflicts_resolver_tab.tsx   | 37 ++++++++
 .../rule_details/three_way_diff_tab.tsx       | 22 -----
 .../components/rule_details/translations.ts   |  7 --
 .../upgrade_prebuilt_rules_table_context.tsx  | 85 ++++++++++---------
 .../use_prebuilt_rules_upgrade_state.ts       | 27 +++---
 21 files changed, 538 insertions(+), 141 deletions(-)
 create mode 100644 x-pack/plugins/security_solution/public/common/components/split_accordion/index.ts
 create mode 100644 x-pack/plugins/security_solution/public/common/components/split_accordion/split_accordion.tsx
 delete mode 100644 x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/diff_components/panel_wrapper.tsx
 create mode 100644 x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/field_upgrade_conflicts_resolver.tsx
 create mode 100644 x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/field_upgrade_conflicts_resolver_header.tsx
 create mode 100644 x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/rule_upgrade_conflicts_resolver.tsx
 create mode 100644 x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/rule_upgrade_info_bar.tsx
 create mode 100644 x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/side_header.tsx
 create mode 100644 x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/translations.tsx
 create mode 100644 x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/final_side/final_side.tsx
 create mode 100644 x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/final_side/final_side_help_info.tsx
 create mode 100644 x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/final_side/translations.ts
 create mode 100644 x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/rule_upgrade_conflicts_resolver_tab.tsx
 delete mode 100644 x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff_tab.tsx

diff --git a/x-pack/plugins/security_solution/public/common/components/split_accordion/index.ts b/x-pack/plugins/security_solution/public/common/components/split_accordion/index.ts
new file mode 100644
index 0000000000000..6b05d7594e20a
--- /dev/null
+++ b/x-pack/plugins/security_solution/public/common/components/split_accordion/index.ts
@@ -0,0 +1,8 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+export * from './split_accordion';
diff --git a/x-pack/plugins/security_solution/public/common/components/split_accordion/split_accordion.tsx b/x-pack/plugins/security_solution/public/common/components/split_accordion/split_accordion.tsx
new file mode 100644
index 0000000000000..668473919b97b
--- /dev/null
+++ b/x-pack/plugins/security_solution/public/common/components/split_accordion/split_accordion.tsx
@@ -0,0 +1,47 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import React from 'react';
+import { EuiAccordion, EuiSplitPanel, useEuiTheme, useGeneratedHtmlId } from '@elastic/eui';
+import { css } from '@emotion/css';
+import type { PropsWithChildren } from 'react';
+
+interface SplitAccordionProps {
+  header: React.ReactNode;
+  initialIsOpen?: boolean;
+  'data-test-subj'?: string;
+}
+
+export const SplitAccordion = ({
+  header,
+  initialIsOpen,
+  'data-test-subj': dataTestSubj,
+  children,
+}: PropsWithChildren<SplitAccordionProps>) => {
+  const accordionId = useGeneratedHtmlId();
+  const { euiTheme } = useEuiTheme();
+
+  return (
+    <EuiSplitPanel.Outer data-test-subj={`${dataTestSubj}Wrapper`} hasBorder>
+      <EuiAccordion
+        id={accordionId}
+        initialIsOpen={initialIsOpen}
+        css={css`
+          .euiAccordion__triggerWrapper {
+            background: ${euiTheme.colors.lightestShade};
+            padding: ${euiTheme.size.m};
+          }
+        `}
+        buttonContent={header}
+      >
+        <EuiSplitPanel.Inner data-test-subj={`${dataTestSubj}Content`} color="transparent">
+          {children}
+        </EuiSplitPanel.Inner>
+      </EuiAccordion>
+    </EuiSplitPanel.Outer>
+  );
+};
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/diff_components/field_diff.tsx b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/diff_components/field_diff.tsx
index 86c85b7b7a89b..7051c7c496e45 100644
--- a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/diff_components/field_diff.tsx
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/diff_components/field_diff.tsx
@@ -8,8 +8,8 @@
 import { EuiFlexGroup, EuiHorizontalRule, EuiTitle } from '@elastic/eui';
 import { camelCase, startCase } from 'lodash';
 import React from 'react';
+import { SplitAccordion } from '../../../../../common/components/split_accordion';
 import { DiffView } from '../json_diff/diff_view';
-import { RuleDiffPanelWrapper } from './panel_wrapper';
 import type { FormattedFieldDiff, FieldDiff } from '../../../model/rule_details/rule_field_diff';
 import { fieldToDisplayNameMap } from './translations';
 
@@ -46,14 +46,24 @@ export const FieldGroupDiffComponent = ({
   fieldsGroupName,
 }: FieldDiffComponentProps) => {
   const { fieldDiffs, shouldShowSubtitles } = ruleDiffs;
+
   return (
-    <RuleDiffPanelWrapper fieldName={fieldsGroupName}>
+    <SplitAccordion
+      header={
+        <EuiTitle data-test-subj="ruleUpgradePerFieldDiffLabel" size="xs">
+          <h5>{fieldToDisplayNameMap[fieldsGroupName] ?? startCase(camelCase(fieldsGroupName))}</h5>
+        </EuiTitle>
+      }
+      initialIsOpen={true}
+      data-test-subj="ruleUpgradePerFieldDiff"
+    >
       {fieldDiffs.map(({ currentVersion, targetVersion, fieldName: specificFieldName }, index) => {
-        const shouldShowSeparator = index !== fieldDiffs.length - 1;
+        const isLast = index === fieldDiffs.length - 1;
+
         return (
           <SubFieldComponent
             key={specificFieldName}
-            shouldShowSeparator={shouldShowSeparator}
+            shouldShowSeparator={!isLast}
             shouldShowSubtitles={shouldShowSubtitles}
             currentVersion={currentVersion}
             targetVersion={targetVersion}
@@ -61,6 +71,6 @@ export const FieldGroupDiffComponent = ({
           />
         );
       })}
-    </RuleDiffPanelWrapper>
+    </SplitAccordion>
   );
 };
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/diff_components/index.ts b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/diff_components/index.ts
index 6effbcf3af931..cef0491a53e22 100644
--- a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/diff_components/index.ts
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/diff_components/index.ts
@@ -7,5 +7,4 @@
 
 export * from './field_diff';
 export * from './header_bar';
-export * from './panel_wrapper';
 export * from './rule_diff_section';
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/diff_components/panel_wrapper.tsx b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/diff_components/panel_wrapper.tsx
deleted file mode 100644
index f0c86a68cafaf..0000000000000
--- a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/diff_components/panel_wrapper.tsx
+++ /dev/null
@@ -1,45 +0,0 @@
-/*
- * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
- * or more contributor license agreements. Licensed under the Elastic License
- * 2.0; you may not use this file except in compliance with the Elastic License
- * 2.0.
- */
-
-import { EuiAccordion, EuiSplitPanel, EuiTitle, useEuiTheme } from '@elastic/eui';
-import { camelCase, startCase } from 'lodash';
-import { css } from '@emotion/css';
-import React from 'react';
-import { fieldToDisplayNameMap } from './translations';
-
-interface RuleDiffPanelWrapperProps {
-  fieldName: string;
-  children: React.ReactNode;
-}
-
-export const RuleDiffPanelWrapper = ({ fieldName, children }: RuleDiffPanelWrapperProps) => {
-  const { euiTheme } = useEuiTheme();
-
-  return (
-    <EuiSplitPanel.Outer data-test-subj="ruleUpgradePerFieldDiffWrapper" hasBorder>
-      <EuiAccordion
-        initialIsOpen={true}
-        css={css`
-          .euiAccordion__triggerWrapper {
-            background: ${euiTheme.colors.lightestShade};
-            padding: ${euiTheme.size.m};
-          }
-        `}
-        id={fieldName}
-        buttonContent={
-          <EuiTitle data-test-subj="ruleUpgradePerFieldDiffLabel" size="xs">
-            <h5>{fieldToDisplayNameMap[fieldName] ?? startCase(camelCase(fieldName))}</h5>
-          </EuiTitle>
-        }
-      >
-        <EuiSplitPanel.Inner data-test-subj="ruleUpgradePerFieldDiffContent" color="transparent">
-          {children}
-        </EuiSplitPanel.Inner>
-      </EuiAccordion>
-    </EuiSplitPanel.Outer>
-  );
-};
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/comparison_side/comparison_side.tsx b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/comparison_side/comparison_side.tsx
index 3a6f3e366d848..9ef207b0bb998 100644
--- a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/comparison_side/comparison_side.tsx
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/comparison_side/comparison_side.tsx
@@ -6,7 +6,6 @@
  */
 
 import React, { useState } from 'react';
-import { EuiSpacer } from '@elastic/eui';
 import { VersionsPicker } from '../versions_picker/versions_picker';
 import type { Version } from '../versions_picker/constants';
 import { SelectedVersions } from '../versions_picker/constants';
@@ -17,6 +16,7 @@ import type {
 } from '../../../../../../../common/api/detection_engine';
 import { getSubfieldChanges } from './get_subfield_changes';
 import { SubfieldChanges } from './subfield_changes';
+import { SideHeader } from '../components/side_header';
 
 interface ComparisonSideProps<FieldName extends keyof DiffableAllFields> {
   fieldName: FieldName;
@@ -42,12 +42,13 @@ export function ComparisonSide<FieldName extends keyof DiffableAllFields>({
 
   return (
     <>
-      <VersionsPicker
-        hasBaseVersion={fieldThreeWayDiff.has_base_version}
-        selectedVersions={selectedVersions}
-        onChange={setSelectedVersions}
-      />
-      <EuiSpacer size="m" />
+      <SideHeader>
+        <VersionsPicker
+          hasBaseVersion={fieldThreeWayDiff.has_base_version}
+          selectedVersions={selectedVersions}
+          onChange={setSelectedVersions}
+        />
+      </SideHeader>
       <SubfieldChanges fieldName={fieldName} subfieldChanges={subfieldChanges} />
     </>
   );
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/comparison_side/utils.ts b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/comparison_side/utils.ts
index fd16366f1a76e..dd52da04982f3 100644
--- a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/comparison_side/utils.ts
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/comparison_side/utils.ts
@@ -26,7 +26,7 @@ export function pickFieldValueForVersion<FieldName extends keyof DiffableAllFiel
   resolvedValue?: DiffableAllFields[FieldName]
 ): DiffableAllFields[FieldName] | undefined {
   if (version === Version.Final) {
-    return resolvedValue ?? fieldThreeWayDiff.merged_version;
+    return resolvedValue;
   }
 
   const versionFieldToPick = `${version}_version` as const;
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/field_upgrade_conflicts_resolver.tsx b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/field_upgrade_conflicts_resolver.tsx
new file mode 100644
index 0000000000000..eeafddfc21f03
--- /dev/null
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/field_upgrade_conflicts_resolver.tsx
@@ -0,0 +1,67 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import React from 'react';
+import { EuiFlexGroup, EuiFlexItem, EuiSpacer, useEuiTheme } from '@elastic/eui';
+import { css } from '@emotion/css';
+import { SplitAccordion } from '../../../../../../common/components/split_accordion';
+import type {
+  DiffableAllFields,
+  DiffableRule,
+  RuleFieldsDiff,
+  ThreeWayDiff,
+} from '../../../../../../../common/api/detection_engine';
+import { ThreeWayDiffConflict } from '../../../../../../../common/api/detection_engine';
+import { ComparisonSide } from '../comparison_side/comparison_side';
+import { FinalSide } from '../final_side/final_side';
+import { FieldUpgradeConflictsResolverHeader } from './field_upgrade_conflicts_resolver_header';
+
+interface FieldUpgradeConflictsResolverProps<FieldName extends keyof RuleFieldsDiff> {
+  fieldName: FieldName;
+  fieldThreeWayDiff: RuleFieldsDiff[FieldName];
+  finalDiffableRule: DiffableRule;
+}
+
+export function FieldUpgradeConflictsResolver<FieldName extends keyof RuleFieldsDiff>({
+  fieldName,
+  fieldThreeWayDiff,
+  finalDiffableRule,
+}: FieldUpgradeConflictsResolverProps<FieldName>): JSX.Element {
+  const { euiTheme } = useEuiTheme();
+  const hasConflict = fieldThreeWayDiff.conflict !== ThreeWayDiffConflict.NONE;
+
+  return (
+    <>
+      <SplitAccordion
+        header={<FieldUpgradeConflictsResolverHeader fieldName={fieldName} />}
+        initialIsOpen={hasConflict}
+        data-test-subj="ruleUpgradePerFieldDiff"
+      >
+        <EuiFlexGroup gutterSize="s" alignItems="flexStart">
+          <EuiFlexItem grow={1}>
+            <ComparisonSide
+              fieldName={fieldName}
+              fieldThreeWayDiff={fieldThreeWayDiff as ThreeWayDiff<DiffableAllFields[FieldName]>}
+              resolvedValue={finalDiffableRule[fieldName] as DiffableAllFields[FieldName]}
+            />
+          </EuiFlexItem>
+          <EuiFlexItem
+            grow={0}
+            css={css`
+              align-self: stretch;
+              border-right: ${euiTheme.border.thin};
+            `}
+          />
+          <EuiFlexItem grow={1}>
+            <FinalSide fieldName={fieldName} finalDiffableRule={finalDiffableRule} />
+          </EuiFlexItem>
+        </EuiFlexGroup>
+      </SplitAccordion>
+      <EuiSpacer size="s" />
+    </>
+  );
+}
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/field_upgrade_conflicts_resolver_header.tsx b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/field_upgrade_conflicts_resolver_header.tsx
new file mode 100644
index 0000000000000..2821a0a179b91
--- /dev/null
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/field_upgrade_conflicts_resolver_header.tsx
@@ -0,0 +1,25 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import React from 'react';
+import { camelCase, startCase } from 'lodash';
+import { EuiTitle } from '@elastic/eui';
+import { fieldToDisplayNameMap } from '../../diff_components/translations';
+
+interface FieldUpgradeConflictsResolverHeaderProps {
+  fieldName: string;
+}
+
+export function FieldUpgradeConflictsResolverHeader({
+  fieldName,
+}: FieldUpgradeConflictsResolverHeaderProps): JSX.Element {
+  return (
+    <EuiTitle data-test-subj="ruleUpgradeFieldDiffLabel" size="xs">
+      <h5>{fieldToDisplayNameMap[fieldName] ?? startCase(camelCase(fieldName))}</h5>
+    </EuiTitle>
+  );
+}
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/rule_upgrade_conflicts_resolver.tsx b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/rule_upgrade_conflicts_resolver.tsx
new file mode 100644
index 0000000000000..57af1b340c776
--- /dev/null
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/rule_upgrade_conflicts_resolver.tsx
@@ -0,0 +1,40 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import React from 'react';
+import type {
+  RuleUpgradeState,
+  SetRuleFieldResolvedValueFn,
+} from '../../../../../rule_management_ui/components/rules_table/upgrade_prebuilt_rules_table/use_prebuilt_rules_upgrade_state';
+import { FieldUpgradeConflictsResolver } from './field_upgrade_conflicts_resolver';
+
+interface RuleUpgradeConflictsResolverProps {
+  ruleUpgradeState: RuleUpgradeState;
+  setRuleFieldResolvedValue: SetRuleFieldResolvedValueFn;
+}
+
+export function RuleUpgradeConflictsResolver({
+  ruleUpgradeState,
+  setRuleFieldResolvedValue,
+}: RuleUpgradeConflictsResolverProps): JSX.Element {
+  const fieldDiffEntries = Object.entries(ruleUpgradeState.diff.fields) as Array<
+    [
+      keyof typeof ruleUpgradeState.diff.fields,
+      Required<typeof ruleUpgradeState.diff.fields>[keyof typeof ruleUpgradeState.diff.fields]
+    ]
+  >;
+  const fields = fieldDiffEntries.map(([fieldName, fieldDiff]) => (
+    <FieldUpgradeConflictsResolver
+      key={fieldName}
+      fieldName={fieldName}
+      fieldThreeWayDiff={fieldDiff}
+      finalDiffableRule={ruleUpgradeState.finalRule}
+    />
+  ));
+
+  return <>{fields}</>;
+}
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/rule_upgrade_info_bar.tsx b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/rule_upgrade_info_bar.tsx
new file mode 100644
index 0000000000000..7ecde8059cc2f
--- /dev/null
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/rule_upgrade_info_bar.tsx
@@ -0,0 +1,47 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import React from 'react';
+import type { RuleUpgradeState } from '../../../../../rule_management_ui/components/rules_table/upgrade_prebuilt_rules_table/use_prebuilt_rules_upgrade_state';
+import {
+  UtilityBar,
+  UtilityBarGroup,
+  UtilityBarSection,
+  UtilityBarText,
+} from '../../../../../../common/components/utility_bar';
+import * as i18n from './translations';
+
+interface UpgradeInfoBarProps {
+  ruleUpgradeState: RuleUpgradeState;
+}
+
+export function RuleUpgradeInfoBar({ ruleUpgradeState }: UpgradeInfoBarProps): JSX.Element {
+  const numOfFieldsWithUpdates = ruleUpgradeState.diff.num_fields_with_updates;
+  const numOfConflicts = ruleUpgradeState.diff.num_fields_with_conflicts;
+
+  return (
+    <UtilityBar>
+      <UtilityBarSection>
+        <UtilityBarGroup>
+          <UtilityBarText dataTestSubj="showingRules">
+            {i18n.NUM_OF_FIELDS_WITH_UPDATES(numOfFieldsWithUpdates)}
+          </UtilityBarText>
+        </UtilityBarGroup>
+        <UtilityBarGroup>
+          <UtilityBarText dataTestSubj="showingRules">
+            {i18n.NUM_OF_CONFLICTS(numOfConflicts)}
+          </UtilityBarText>
+        </UtilityBarGroup>
+      </UtilityBarSection>
+      <UtilityBarSection>
+        <UtilityBarGroup>
+          <i18n.RuleUpgradeHelper />
+        </UtilityBarGroup>
+      </UtilityBarSection>
+    </UtilityBar>
+  );
+}
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/side_header.tsx b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/side_header.tsx
new file mode 100644
index 0000000000000..574e3f526f856
--- /dev/null
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/side_header.tsx
@@ -0,0 +1,29 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import type { PropsWithChildren } from 'react';
+import React from 'react';
+import { EuiFlexGroup, EuiFlexItem, EuiHorizontalRule, useEuiTheme } from '@elastic/eui';
+import { css } from '@emotion/css';
+
+export function SideHeader({ children }: PropsWithChildren<{}>) {
+  const { euiTheme } = useEuiTheme();
+
+  return (
+    <>
+      <EuiFlexGroup
+        alignItems="center"
+        css={css`
+          height: ${euiTheme.size.xxl};
+        `}
+      >
+        <EuiFlexItem>{children}</EuiFlexItem>
+      </EuiFlexGroup>
+      <EuiHorizontalRule margin="s" />
+    </>
+  );
+}
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/translations.tsx b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/translations.tsx
new file mode 100644
index 0000000000000..620b3ac1c0ba8
--- /dev/null
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/components/translations.tsx
@@ -0,0 +1,62 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import React from 'react';
+import { EuiLink } from '@elastic/eui';
+import { i18n } from '@kbn/i18n';
+import { FormattedMessage } from '@kbn/i18n-react';
+import { useKibana } from '../../../../../../common/lib/kibana/kibana_react';
+
+export const NUM_OF_FIELDS_WITH_UPDATES = (count: number) =>
+  i18n.translate(
+    'xpack.securitySolution.detectionEngine.rules.upgradeRules.diffTab.fieldsWithUpdates',
+    {
+      values: { count },
+      defaultMessage: 'Upgrade has {count} {count, plural, one {field} other {fields}}',
+    }
+  );
+
+export const NUM_OF_CONFLICTS = (count: number) =>
+  i18n.translate(
+    'xpack.securitySolution.detectionEngine.rules.upgradeRules.diffTab.numOfConflicts',
+    {
+      values: { count },
+      defaultMessage: '{count} {count, plural, one {conflict} other {conflicts}}',
+    }
+  );
+
+const UPGRADE_RULES_DOCS_LINK = i18n.translate(
+  'xpack.securitySolution.detectionEngine.rules.upgradeRules.updateYourRulesDocsLink',
+  {
+    defaultMessage: 'update your rules',
+  }
+);
+
+export function RuleUpgradeHelper(): JSX.Element {
+  const {
+    docLinks: {
+      links: {
+        securitySolution: { manageDetectionRules },
+      },
+    },
+  } = useKibana().services;
+  const manageDetectionRulesSnoozeSection = `${manageDetectionRules}#edit-rules-settings`;
+
+  return (
+    <FormattedMessage
+      id="xpack.securitySolution.detectionEngine.rules.upgradeRules.ruleUpgradeHelper"
+      defaultMessage="Understand how to&nbsp;{docsLink}."
+      values={{
+        docsLink: (
+          <EuiLink href={manageDetectionRulesSnoozeSection} target="_blank">
+            {UPGRADE_RULES_DOCS_LINK}
+          </EuiLink>
+        ),
+      }}
+    />
+  );
+}
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/final_side/final_side.tsx b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/final_side/final_side.tsx
new file mode 100644
index 0000000000000..0685d064b32d0
--- /dev/null
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/final_side/final_side.tsx
@@ -0,0 +1,35 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import React from 'react';
+import { EuiTitle } from '@elastic/eui';
+import type { DiffableRule } from '../../../../../../../common/api/detection_engine';
+import { FieldReadOnly } from '../final_readonly/field_readonly';
+import { SideHeader } from '../components/side_header';
+import { FinalSideHelpInfo } from './final_side_help_info';
+import * as i18n from './translations';
+
+interface FinalSideProps {
+  fieldName: string;
+  finalDiffableRule: DiffableRule;
+}
+
+export function FinalSide({ fieldName, finalDiffableRule }: FinalSideProps): JSX.Element {
+  return (
+    <>
+      <SideHeader>
+        <EuiTitle size="xs">
+          <h3>
+            {i18n.UPGRADED_VERSION}
+            <FinalSideHelpInfo />
+          </h3>
+        </EuiTitle>
+      </SideHeader>
+      <FieldReadOnly fieldName={fieldName} finalDiffableRule={finalDiffableRule} />
+    </>
+  );
+}
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/final_side/final_side_help_info.tsx b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/final_side/final_side_help_info.tsx
new file mode 100644
index 0000000000000..766692e9efecd
--- /dev/null
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/final_side/final_side_help_info.tsx
@@ -0,0 +1,43 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import React from 'react';
+import { useToggle } from 'react-use';
+import { EuiPopover, EuiText, EuiButtonIcon } from '@elastic/eui';
+import { FormattedMessage } from '@kbn/i18n-react';
+
+/**
+ * Theme doesn't expose width variables. Using provided size variables will require
+ * multiplying it by another magic constant.
+ *
+ * 320px width looks
+ * like a [commonly used width in EUI](https://github.com/search?q=repo%3Aelastic%2Feui%20320&type=code).
+ */
+const POPOVER_WIDTH = 320;
+
+export function FinalSideHelpInfo(): JSX.Element {
+  const [isPopoverOpen, togglePopover] = useToggle(false);
+
+  const button = (
+    <EuiButtonIcon
+      iconType="questionInCircle"
+      onClick={togglePopover}
+      aria-label="Open help popover"
+    />
+  );
+
+  return (
+    <EuiPopover button={button} isOpen={isPopoverOpen} closePopover={togglePopover}>
+      <EuiText style={{ width: POPOVER_WIDTH }} size="s">
+        <FormattedMessage
+          id="xpack.securitySolution.detectionEngine.rules.upgradeRules.upgradeHelpText"
+          defaultMessage="Choose field values used in the upgraded rule. "
+        />
+      </EuiText>
+    </EuiPopover>
+  );
+}
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/final_side/translations.ts b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/final_side/translations.ts
new file mode 100644
index 0000000000000..aa9b4885a964d
--- /dev/null
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/final_side/translations.ts
@@ -0,0 +1,15 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import { i18n } from '@kbn/i18n';
+
+export const UPGRADED_VERSION = i18n.translate(
+  'xpack.securitySolution.detectionEngine.rules.upgradeRules.upgradedVersion',
+  {
+    defaultMessage: 'Upgraded version',
+  }
+);
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/rule_upgrade_conflicts_resolver_tab.tsx b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/rule_upgrade_conflicts_resolver_tab.tsx
new file mode 100644
index 0000000000000..10823b8045c96
--- /dev/null
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff/rule_upgrade_conflicts_resolver_tab.tsx
@@ -0,0 +1,37 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import React from 'react';
+import { EuiSpacer } from '@elastic/eui';
+import type {
+  RuleUpgradeState,
+  SetRuleFieldResolvedValueFn,
+} from '../../../../rule_management_ui/components/rules_table/upgrade_prebuilt_rules_table/use_prebuilt_rules_upgrade_state';
+import { RuleUpgradeInfoBar } from './components/rule_upgrade_info_bar';
+import { RuleUpgradeConflictsResolver } from './components/rule_upgrade_conflicts_resolver';
+
+interface RuleUpgradeConflictsResolverTabProps {
+  ruleUpgradeState: RuleUpgradeState;
+  setRuleFieldResolvedValue: SetRuleFieldResolvedValueFn;
+}
+
+export function RuleUpgradeConflictsResolverTab({
+  ruleUpgradeState,
+  setRuleFieldResolvedValue,
+}: RuleUpgradeConflictsResolverTabProps): JSX.Element {
+  return (
+    <>
+      <EuiSpacer size="s" />
+      <RuleUpgradeInfoBar ruleUpgradeState={ruleUpgradeState} />
+      <EuiSpacer size="s" />
+      <RuleUpgradeConflictsResolver
+        ruleUpgradeState={ruleUpgradeState}
+        setRuleFieldResolvedValue={setRuleFieldResolvedValue}
+      />
+    </>
+  );
+}
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff_tab.tsx b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff_tab.tsx
deleted file mode 100644
index 5117fa2d7b93b..0000000000000
--- a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/three_way_diff_tab.tsx
+++ /dev/null
@@ -1,22 +0,0 @@
-/*
- * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
- * or more contributor license agreements. Licensed under the Elastic License
- * 2.0; you may not use this file except in compliance with the Elastic License
- * 2.0.
- */
-
-import React from 'react';
-import type { DiffableRule } from '../../../../../common/api/detection_engine';
-import type { SetFieldResolvedValueFn } from '../../../rule_management_ui/components/rules_table/upgrade_prebuilt_rules_table/use_prebuilt_rules_upgrade_state';
-
-interface ThreeWayDiffTabProps {
-  finalDiffableRule: DiffableRule;
-  setFieldResolvedValue: SetFieldResolvedValueFn;
-}
-
-export function ThreeWayDiffTab({
-  finalDiffableRule,
-  setFieldResolvedValue,
-}: ThreeWayDiffTabProps): JSX.Element {
-  return <>{JSON.stringify(finalDiffableRule)}</>;
-}
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/translations.ts b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/translations.ts
index f0b96bad1aff5..89c22a285e327 100644
--- a/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/translations.ts
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management/components/rule_details/translations.ts
@@ -28,13 +28,6 @@ export const UPDATES_TAB_LABEL = i18n.translate(
   }
 );
 
-export const DIFF_TAB_LABEL = i18n.translate(
-  'xpack.securitySolution.detectionEngine.ruleDetails.diffTabLabel',
-  {
-    defaultMessage: 'Diff',
-  }
-);
-
 export const JSON_VIEW_UPDATES_TAB_LABEL = i18n.translate(
   'xpack.securitySolution.detectionEngine.ruleDetails.jsonViewUpdatesTabLabel',
   {
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management_ui/components/rules_table/upgrade_prebuilt_rules_table/upgrade_prebuilt_rules_table_context.tsx b/x-pack/plugins/security_solution/public/detection_engine/rule_management_ui/components/rules_table/upgrade_prebuilt_rules_table/upgrade_prebuilt_rules_table_context.tsx
index efd63e5da6872..997f85d3ddce0 100644
--- a/x-pack/plugins/security_solution/public/detection_engine/rule_management_ui/components/rules_table/upgrade_prebuilt_rules_table/upgrade_prebuilt_rules_table_context.tsx
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management_ui/components/rules_table/upgrade_prebuilt_rules_table/upgrade_prebuilt_rules_table_context.tsx
@@ -9,7 +9,7 @@ import type { Dispatch, SetStateAction } from 'react';
 import React, { createContext, useCallback, useContext, useMemo, useState } from 'react';
 import { EuiButton, EuiToolTip } from '@elastic/eui';
 import { useIsExperimentalFeatureEnabled } from '../../../../../common/hooks/use_experimental_features';
-import { ThreeWayDiffTab } from '../../../../rule_management/components/rule_details/three_way_diff_tab';
+import { RuleUpgradeConflictsResolverTab } from '../../../../rule_management/components/rule_details/three_way_diff/rule_upgrade_conflicts_resolver_tab';
 import { PerFieldRuleDiffTab } from '../../../../rule_management/components/rule_details/per_field_rule_diff_tab';
 import { useIsUpgradingSecurityPackages } from '../../../../rule_management/logic/use_upgrade_security_packages';
 import { useInstalledSecurityJobs } from '../../../../../common/components/ml/hooks/use_installed_security_jobs';
@@ -140,7 +140,7 @@ export const UpgradePrebuiltRulesTableContextProvider = ({
     filterOptions,
     rules: ruleUpgradeInfos,
   });
-  const { rulesUpgradeState, setFieldResolvedValue } =
+  const { rulesUpgradeState, setRuleFieldResolvedValue } =
     usePrebuiltRulesUpgradeState(filteredRuleUpgradeInfos);
 
   // Wrapper to add confirmation modal for users who may be running older ML Jobs that would
@@ -225,7 +225,46 @@ export const UpgradePrebuiltRulesTableContextProvider = ({
         return [];
       }
 
-      const extraTabs = [
+      const jsonViewUpdates = {
+        id: 'jsonViewUpdates',
+        name: (
+          <EuiToolTip position="top" content={i18n.UPDATE_FLYOUT_JSON_VIEW_TOOLTIP_DESCRIPTION}>
+            <>{ruleDetailsI18n.JSON_VIEW_UPDATES_TAB_LABEL}</>
+          </EuiToolTip>
+        ),
+        content: (
+          <TabContentPadding>
+            <RuleDiffTab
+              oldRule={ruleUpgradeState.current_rule}
+              newRule={ruleUpgradeState.target_rule}
+            />
+          </TabContentPadding>
+        ),
+      };
+
+      if (isPrebuiltRulesCustomizationEnabled) {
+        return [
+          {
+            id: 'updates',
+            name: (
+              <EuiToolTip position="top" content={i18n.UPDATE_FLYOUT_PER_FIELD_TOOLTIP_DESCRIPTION}>
+                <>{ruleDetailsI18n.UPDATES_TAB_LABEL}</>
+              </EuiToolTip>
+            ),
+            content: (
+              <TabContentPadding>
+                <RuleUpgradeConflictsResolverTab
+                  ruleUpgradeState={ruleUpgradeState}
+                  setRuleFieldResolvedValue={setRuleFieldResolvedValue}
+                />
+              </TabContentPadding>
+            ),
+          },
+          jsonViewUpdates,
+        ];
+      }
+
+      return [
         {
           id: 'updates',
           name: (
@@ -239,46 +278,10 @@ export const UpgradePrebuiltRulesTableContextProvider = ({
             </TabContentPadding>
           ),
         },
-        {
-          id: 'jsonViewUpdates',
-          name: (
-            <EuiToolTip position="top" content={i18n.UPDATE_FLYOUT_JSON_VIEW_TOOLTIP_DESCRIPTION}>
-              <>{ruleDetailsI18n.JSON_VIEW_UPDATES_TAB_LABEL}</>
-            </EuiToolTip>
-          ),
-          content: (
-            <TabContentPadding>
-              <RuleDiffTab
-                oldRule={ruleUpgradeState.current_rule}
-                newRule={ruleUpgradeState.target_rule}
-              />
-            </TabContentPadding>
-          ),
-        },
+        jsonViewUpdates,
       ];
-
-      if (isPrebuiltRulesCustomizationEnabled) {
-        extraTabs.unshift({
-          id: 'diff',
-          name: (
-            <EuiToolTip position="top" content={i18n.UPDATE_FLYOUT_PER_FIELD_TOOLTIP_DESCRIPTION}>
-              <>{ruleDetailsI18n.DIFF_TAB_LABEL}</>
-            </EuiToolTip>
-          ),
-          content: (
-            <TabContentPadding>
-              <ThreeWayDiffTab
-                finalDiffableRule={ruleUpgradeState.finalRule}
-                setFieldResolvedValue={setFieldResolvedValue}
-              />
-            </TabContentPadding>
-          ),
-        });
-      }
-
-      return extraTabs;
     },
-    [rulesUpgradeState, setFieldResolvedValue, isPrebuiltRulesCustomizationEnabled]
+    [rulesUpgradeState, setRuleFieldResolvedValue, isPrebuiltRulesCustomizationEnabled]
   );
   const filteredRules = useMemo(
     () => filteredRuleUpgradeInfos.map((rule) => rule.target_rule),
diff --git a/x-pack/plugins/security_solution/public/detection_engine/rule_management_ui/components/rules_table/upgrade_prebuilt_rules_table/use_prebuilt_rules_upgrade_state.ts b/x-pack/plugins/security_solution/public/detection_engine/rule_management_ui/components/rules_table/upgrade_prebuilt_rules_table/use_prebuilt_rules_upgrade_state.ts
index 86f2293d312fa..feafc1a6948ab 100644
--- a/x-pack/plugins/security_solution/public/detection_engine/rule_management_ui/components/rules_table/upgrade_prebuilt_rules_table/use_prebuilt_rules_upgrade_state.ts
+++ b/x-pack/plugins/security_solution/public/detection_engine/rule_management_ui/components/rules_table/upgrade_prebuilt_rules_table/use_prebuilt_rules_upgrade_state.ts
@@ -28,7 +28,7 @@ export interface RuleUpgradeState extends RuleUpgradeInfoForReview {
   hasUnresolvedConflicts: boolean;
 }
 export type RulesUpgradeState = Record<RuleSignatureId, RuleUpgradeState>;
-export type SetFieldResolvedValueFn<
+export type SetRuleFieldResolvedValueFn<
   FieldName extends keyof DiffableAllFields = keyof DiffableAllFields
 > = (params: {
   ruleId: RuleObjectId;
@@ -41,22 +41,25 @@ type RulesResolvedConflicts = Record<string, RuleResolvedConflicts>;
 
 interface UseRulesUpgradeStateResult {
   rulesUpgradeState: RulesUpgradeState;
-  setFieldResolvedValue: SetFieldResolvedValueFn;
+  setRuleFieldResolvedValue: SetRuleFieldResolvedValueFn;
 }
 
 export function usePrebuiltRulesUpgradeState(
   ruleUpgradeInfos: RuleUpgradeInfoForReview[]
 ): UseRulesUpgradeStateResult {
   const [rulesResolvedConflicts, setRulesResolvedConflicts] = useState<RulesResolvedConflicts>({});
-  const setFieldResolvedValue = useCallback((...[params]: Parameters<SetFieldResolvedValueFn>) => {
-    setRulesResolvedConflicts((prevRulesResolvedConflicts) => ({
-      ...prevRulesResolvedConflicts,
-      [params.ruleId]: {
-        ...(prevRulesResolvedConflicts[params.ruleId] ?? {}),
-        [params.fieldName]: params.resolvedValue,
-      },
-    }));
-  }, []);
+  const setRuleFieldResolvedValue = useCallback(
+    (...[params]: Parameters<SetRuleFieldResolvedValueFn>) => {
+      setRulesResolvedConflicts((prevRulesResolvedConflicts) => ({
+        ...prevRulesResolvedConflicts,
+        [params.ruleId]: {
+          ...(prevRulesResolvedConflicts[params.ruleId] ?? {}),
+          [params.fieldName]: params.resolvedValue,
+        },
+      }));
+    },
+    []
+  );
   const rulesUpgradeState = useMemo(() => {
     const state: RulesUpgradeState = {};
 
@@ -80,7 +83,7 @@ export function usePrebuiltRulesUpgradeState(
 
   return {
     rulesUpgradeState,
-    setFieldResolvedValue,
+    setRuleFieldResolvedValue,
   };
 }