Filter By Brand in opencart

<?xml version="1.0" encoding="UTF-8"?>
<modification>
<name>Brand By Filter</name>
<id>Brand By Filter</id>
<code>OCMP_BBF</code>
<version>3.0.2</version>
<vqmver required="true">2.4.0</vqmver>
<author>ManiNalliapppan</author>


<file path="catalog/controller/product/category.php">

<operation>
            <search><![CDATA[$results = $this->model_catalog_category->getCategories($category_id);]]></search>
            <add position="after"><![CDATA[// get manufacturers for child categories
$categoryids_with_childs = array();
$categoryids_with_childs = $this->model_catalog_category->getCategoriesByParentId($category_id);

array_push($categoryids_with_childs, $category_id);
$manufacturers = $this->model_catalog_manufacturer->getManufacturersByCategories($categoryids_with_childs);

$data['manufacturer_filters'] = array();

$data['manufacturer_filters'][] = array(
'text'  => $this->language->get('All'),
'value' => '0',
'href'  => $this->url->link('product/category', 'path=' . $this->request->get['path'] . $url . '&manufacturer_filter=0')
);

if(is_array($manufacturers) && count($manufacturers) > 0){
foreach ($manufacturers as $man){
$data['manufacturer_filters'][] = array(
'text'  => $man['name'] . " (".$man['products_total'].")",
'value' => $man['manufacturer_id'],
'href'  => $this->url->link('product/category', 'path=' . $this->request->get['path'] . $url . '&manufacturer_filter=' . $man['manufacturer_id'])
);
}



}
]]></add>
        </operation>

<operation>
            <search ><![CDATA[$this->load->model('catalog/product');]]></search>
            <add position="after"><![CDATA[$this->load->model('catalog/manufacturer');
]]></add>
        </operation>
  <operation>
            <search ><![CDATA['order'              => $order,]]></search>
            <add position="after"><![CDATA[ 'brandf'=>$brandf, ]]></add>
        </operation>
  <operation>
            <search ><![CDATA[ $data['limit'] = $limit;]]></search>
            <add position="after"><![CDATA[ $data['brandf'] = $brandf; ]]></add>
        </operation>
  <operation>
            <search ><![CDATA[$this->load->model('tool/image');]]></search>
            <add position="after"><![CDATA[if (isset($this->request->get['manufacturer_filter'])) {
$brandf = $this->request->get['manufacturer_filter'];
}
else
{
$brandf = '';
}
]]></add>
        </operation>


<operation>
            <search ><![CDATA['sort'               => $sort,]]></search>
            <add position="after"><![CDATA[ 'manufacturer_filter' => $brandf,
'filter_manufacturer_id' => $brandf,
]]></add>
        </operation>
 

    </file>

<file path="catalog/model/catalog/category.php">

<operation>
            <search ><![CDATA[public function getCategoryFilters($category_id) {]]></search>
            <add position="before"><![CDATA[public function getCategoriesByParentId($category_id) {
$category_data = array();

$category_query = $this->db->query("SELECT category_id FROM " . DB_PREFIX . "category WHERE parent_id = '" . (int)$category_id . "'");

foreach ($category_query->rows as $category) {
$category_data[] = $category['category_id'];

$children = $this->getCategoriesByParentId($category['category_id']);

if ($children) {
$category_data = array_merge($children, $category_data);
}
}

return $category_data;
}]]></add>
</operation>

</file>

<file path="catalog/model/catalog/manufacturer.php">

<operation>
            <search ><![CDATA[public function getManufacturers($data = array()) {]]></search>
            <add position="before"><![CDATA[public function getManufacturersByCategories($category_ids) {
if (is_array($category_ids) && count($category_ids) > 0){
$category_ids = implode(",", $category_ids);
$query = $this->db->query("SELECT m.manufacturer_id, m.name, COUNT(p.product_id) AS products_total FROM " . DB_PREFIX . "product_to_category AS pc LEFT JOIN " . DB_PREFIX . "product AS p ON p.product_id = pc.product_id LEFT JOIN " . DB_PREFIX . "manufacturer AS m ON m.manufacturer_id = p.manufacturer_id WHERE pc.category_id IN (".$category_ids.") AND p.status = 1 AND p.quantity > 0 GROUP BY m.manufacturer_id ORDER BY m.name ASC");
return $query->rows;
}
return false;
}
]]></add>
</operation>

</file>

<file path="catalog/language/en-gb/product/category.php">

<operation>
            <search position="before"><![CDATA[$_['text_limit']        = 'Show:';]]></search>
            <add trim="true"><![CDATA[$_['text_brand'] = 'Brand';]]></add>
        </operation>

    </file>
</modification>




Save this code in install.xml.