[FEAT] Redirect single search result to product page

app/code/core/Mage/Catalog/etc/config.xml

@@ -711,22 +711,6 @@
                     </catalog>
                 </observers>
             </sales_convert_quote_item_to_order_item>
-            <controller_action_predispatch_catalogsearch_advanced_index>
-                <observers>
-                    <disable_advanced_search>
-                        <class>catalog/observer_disableAdvancedSearch</class>
-                        <method>execute</method>
-                    </disable_advanced_search>
-                </observers>
-            </controller_action_predispatch_catalogsearch_advanced_index>
-            <controller_action_predispatch_catalogsearch_advanced_result>
-                <observers>
-                    <disable_advanced_search>
-                        <class>catalog/observer_disableAdvancedSearch</class>
-                        <method>execute</method>
-                    </disable_advanced_search>
-                </observers>
-            </controller_action_predispatch_catalogsearch_advanced_result>
         </events>
         <translate>
             <modules>
@@ -837,9 +821,6 @@
                 <interval_division_limit>9</interval_division_limit>
                 <display_product_count>1</display_product_count>
             </layered_navigation>
-            <search>
-                <enable_advanced_search>1</enable_advanced_search>
-            </search>
         </catalog>
         <system>
             <media_storage_configuration>

app/code/core/Mage/Catalog/etc/system.xml

@@ -474,20 +474,6 @@
                     </fields>
                 </layer>
 -->
-
-                <search>
-                    <fields>
-                        <enable_advanced_search translate="label">
-                            <label>Enable Advanced Search</label>
-                            <frontend_type>select</frontend_type>
-                            <source_model>adminhtml/system_config_source_enabledisable</source_model>
-                            <sort_order>800</sort_order>
-                            <show_in_default>1</show_in_default>
-                            <show_in_website>1</show_in_website>
-                            <show_in_store>1</show_in_store>
-                        </enable_advanced_search>
-                    </fields>
-                </search>
             </groups>
         </catalog>
         <design>

app/code/core/Mage/CatalogSearch/Helper/Data.php

@@ -354,4 +354,28 @@ public function getEngine()
 
         return $this->_engine;
     }
+
+    /**
+     * @SuppressWarnings("PHPMD.StaticAccess")
+     */
+    public function isNotEnabled(): bool
+    {
+        return !Mage::getStoreConfigFlag('catalog/advanced_search/enabled');
+    }
+
+    /**
+     * @SuppressWarnings("PHPMD.StaticAccess")
+     */
+    public function isRedirectSingleSearchResult(): bool
+    {
+        return Mage::getStoreConfigFlag('catalog/search/redirect_to_single_search_result');
+    }
+
+    /**
+     * @SuppressWarnings("PHPMD.StaticAccess")
+     */
+    public function getNoRoutePath(): string
+    {
+        return $this->_getUrl(Mage::getStoreConfig('web/default/cms_no_route'));
+    }
 }

app/code/core/Mage/Catalog/Model/Observer/DisableAdvancedSearch.php → app/code/core/Mage/CatalogSearch/Model/Observer/DisableAdvancedSearch.php

@@ -20,7 +20,7 @@
  * @category   Mage
  * @package    Mage_Catalog
  */
-class Mage_Catalog_Model_Observer_DisableAdvancedSearch
+class Mage_CatalogSearch_Model_Observer_DisableAdvancedSearch implements Mage_Core_Observer_Interface
 {
     /**
      * Disable Advanced Search at storeview scope
@@ -29,8 +29,7 @@ class Mage_Catalog_Model_Observer_DisableAdvancedSearch
      */
     public function execute(Varien_Event_Observer $observer): void
     {
-        /** @var Mage_Catalog_Helper_Search $helper */
-        $helper = Mage::helper('catalog/search');
+        $helper = Mage::helper('catalogsearch');
         if ($helper->isNotEnabled()) {
             $observer->getControllerAction()->getResponse()->setRedirect($helper->getNoRoutePath());
         }

app/code/core/Mage/CatalogSearch/Model/Observer/SingleSearchResult.php

@@ -0,0 +1,59 @@
+<?php
+
+/**
+ * OpenMage
+ *
+ * This source file is subject to the Open Software License (OSL 3.0)
+ * that is bundled with this package in the file LICENSE.txt.
+ * It is also available at https://opensource.org/license/osl-3-0-php
+ *
+ * @category   Mage
+ * @package    Mage_Catalog
+ * @copyright  Copyright (c) 2006-2020 Magento, Inc. (https://www.magento.com)
+ * @copyright  Copyright (c) 2019-2024 The OpenMage Contributors (https://www.openmage.org)
+ * @license    https://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
+ */
+
+/**
+ * Catalog Observer
+ *
+ * @category   Mage
+ * @package    Mage_Catalog
+ */
+class Mage_CatalogSearch_Model_Observer_SingleSearchResult implements Mage_Core_Observer_Interface
+{
+    /**
+     * Product list block name in layout
+     */
+    public const RESULT_BLOCK_NAME = 'search_result_list';
+
+    /**
+     * Redirect single search result to product page
+     *
+     * @SuppressWarnings("PHPMD.ExitExpression")
+     * @SuppressWarnings("PHPMD.StaticAccess")
+     */
+    public function execute(Varien_Event_Observer $observer): void
+    {
+        $helper = Mage::helper('catalogsearch');
+
+        if (!$helper->isRedirectSingleSearchResult()) {
+            return;
+        }
+
+        /** @var Mage_Catalog_Block_Product_List $block */
+        $block = Mage::app()->getLayout()->getBlock(self::RESULT_BLOCK_NAME);
+        if ($block) {
+            $collection = $block->getLoadedProductCollection();
+            if ($collection && $collection->getSize() === 1) {
+                /** @var Mage_Catalog_Model_Product $product */
+                $product = $collection->getFirstItem();
+                $url = $product->getProductUrl();
+                if ($url) {
+                    Mage::app()->getResponse()->setRedirect($url)->sendResponse();
+                    exit; //stop everything else
+                }
+            }
+        }
+    }
+}

app/code/core/Mage/CatalogSearch/etc/config.xml

@@ -96,6 +96,36 @@
                 </catalogsearch>
             </updates>
         </layout>
+        <events>
+            <controller_action_predispatch_catalogsearch_advanced_index>
+                <observers>
+                    <disable_advanced_search>
+                        <class>catalogsearch/observer_disableAdvancedSearch</class>
+                    </disable_advanced_search>
+                </observers>
+            </controller_action_predispatch_catalogsearch_advanced_index>
+            <controller_action_predispatch_catalogsearch_advanced_result>
+                <observers>
+                    <disable_advanced_search>
+                        <class>catalogsearch/observer_disableAdvancedSearch</class>
+                    </disable_advanced_search>
+                </observers>
+            </controller_action_predispatch_catalogsearch_advanced_result>
+            <controller_action_layout_render_before_catalogsearch_result_index>
+                <observers>
+                    <single_search_result>
+                        <model>catalogsearch/observer_singleSearchResult</model>
+                    </single_search_result>
+                </observers>
+            </controller_action_layout_render_before_catalogsearch_result_index>
+            <controller_action_layout_render_before_catalogsearch_advanced_result>
+                <observers>
+                    <single_search_result>
+                        <model>catalogsearch/observer_singleSearchResult</model>
+                    </single_search_result>
+                </observers>
+            </controller_action_layout_render_before_catalogsearch_advanced_result>
+        </events>
     </frontend>
     <adminhtml>
         <translate>
@@ -129,7 +159,11 @@
                 <search_separator>OR</search_separator>
                 <use_layered_navigation_count>2000</use_layered_navigation_count>
                 <show_autocomplete_results_count>1</show_autocomplete_results_count>
+                <redirect_to_single_search_result>1</redirect_to_single_search_result>
             </search>
+            <advanced_search>
+                <enabled>1</enabled>
+            </advanced_search>
         </catalog>
     </default>
 </config>

app/code/core/Mage/CatalogSearch/etc/system.xml

@@ -111,8 +111,28 @@
                             <show_in_website>1</show_in_website>
                             <show_in_store>1</show_in_store>
                         </show_autocomplete_results_count>
+                        <redirect_to_single_search_result translate="label">
+                            <label>Redirect single search result to product</label>
+                            <frontend_type>select</frontend_type>
+                            <source_model>adminhtml/system_config_source_enabledisable</source_model>
+                            <sort_order>80</sort_order>
+                            <show_in_default>1</show_in_default>
+                            <show_in_website>1</show_in_website>
+                            <show_in_store>1</show_in_store>
+                        </redirect_to_single_search_result>
                     </fields>
                 </search>
+                <advanced_search>
+                    <enabled translate="label">
+                        <label>Enable Advanced Search</label>
+                        <frontend_type>select</frontend_type>
+                        <source_model>adminhtml/system_config_source_enabledisable</source_model>
+                        <sort_order>1</sort_order>
+                        <show_in_default>1</show_in_default>
+                        <show_in_website>1</show_in_website>
+                        <show_in_store>1</show_in_store>
+                    </enabled>
+                </advanced_search>
             </groups>
         </catalog>
     </sections>

app/code/core/Mage/Core/Model/App.php

@@ -1413,15 +1413,23 @@ public function dispatchEvent($eventName, $args)
                         break;
                     case 'object':
                     case 'model':
-                        $method = $obs['method'];
                         $observer->addData($args);
                         $object = Mage::getModel($obs['model']);
+                        if ($object instanceof Mage_Core_Observer_Interface) {
+                            $method = 'execute';
+                        } else {
+                            $method = $obs['method'];
+                        }
                         $this->_callObserverMethod($object, $method, $observer, $obsName);
                         break;
                     default:
-                        $method = $obs['method'];
                         $observer->addData($args);
                         $object = Mage::getSingleton($obs['model']);
+                        if ($object instanceof Mage_Core_Observer_Interface) {
+                            $method = 'execute';
+                        } else {
+                            $method = $obs['method'];
+                        }
                         $this->_callObserverMethod($object, $method, $observer, $obsName);
                         break;
                 }

app/code/core/Mage/Core/Observer/Interface.php

@@ -0,0 +1,26 @@
+<?php
+
+/**
+ * OpenMage
+ *
+ * This source file is subject to the Open Software License (OSL 3.0)
+ * that is bundled with this package in the file LICENSE.txt.
+ * It is also available at https://opensource.org/license/osl-3-0-php
+ *
+ * @category   Mage
+ * @package    Mage_Catalog
+ * @copyright  Copyright (c) 2006-2020 Magento, Inc. (https://www.magento.com)
+ * @copyright  Copyright (c) 2019-2024 The OpenMage Contributors (https://www.openmage.org)
+ * @license    https://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
+ */
+
+/**
+ * Observer interface
+ *
+ * @category   Mage
+ * @package    Mage_Core
+ */
+interface Mage_Core_Observer_Interface
+{
+    public function execute(Varien_Event_Observer $observer): void;
+}

app/locale/en_US/Mage_Catalog.csv

@@ -284,7 +284,6 @@
 "Email","Email"
 "Email to a Friend","Email to a Friend"
 "Empty","Empty"
-"Enable Advanced Search","Enable Advanced Search"
 "Enable MAP","Enable MAP"
 "Enable Qty Increments","Enable Qty Increments"
 "Enable WYSIWYG","Enable WYSIWYG"

app/locale/en_US/Mage_CatalogSearch.csv

@@ -12,6 +12,7 @@
 "Catalog Search","Catalog Search"
 "Catalog Search Index","Catalog Search Index"
 "Don't see what you're looking for?","Don't see what you're looking for?"
+"Enable Advanced Search","Enable Advanced Search"
 "Enter ""0"" to enable layered navigation for any number of results.","Enter ""0"" to enable layered navigation for any number of results."
 "Go","Go"
 "Go to Home Page","Go to Home Page"
@@ -31,6 +32,7 @@
 "Popular Search Terms","Popular Search Terms"
 "Quick Search Form","Quick Search Form"
 "Rebuild Catalog product fulltext search index","Rebuild Catalog product fulltext search index"
+"Redirect single search result to product","Redirect single search result to product"
 "Relevance","Relevance"
 "Results","Results"
 "Search","Search"