Fix Product categories, Product Tags & Keyword filter not working in …

…Products block (#8377)

* Fix product categories & keyword filter not working

* Fix Product tags filter not working

* Make code readable by creating functions for the different parts of the query.

Functions:
- get_filter_by_product_categories_or_tags_query
- get_filter_by_keyword_query

Also rename the function `get_queries_by_attributes` to `get_queries_by_custom_attributes` to make it more clear what it does.

* Make function generic by including all taxonomies

As user can add custom taxonomies, we need to make sure that we include all taxonomies in the query.

To fetch all product taxonomies, I used following function:
```php
get_taxonomies( array( 'object_type' => array( 'product' ) ), 'names' )
```

* Minor improvements based on PR feedback

* Move null check for tax_query to function

src/BlockTypes/ProductQuery.php

@@ -160,8 +160,10 @@ public function build_query( $query ) {
 			$common_query_values,
 			$this->get_global_query( $parsed_block ),
 			$this->get_custom_orderby_query( $query['orderby'] ),
-			$this->get_queries_by_attributes( $parsed_block ),
-			$this->get_queries_by_applied_filters()
+			$this->get_queries_by_custom_attributes( $parsed_block ),
+			$this->get_queries_by_applied_filters(),
+			$this->get_filter_by_taxonomies_query( $query ),
+			$this->get_filter_by_keyword_query( $query )
 		);
 	}
 
@@ -182,7 +184,7 @@ private function get_products_ids_by_attributes( $parsed_block ) {
 				'meta_query'     => array(),
 				'tax_query'      => array(),
 			),
-			$this->get_queries_by_attributes( $parsed_block ),
+			$this->get_queries_by_custom_attributes( $parsed_block ),
 			$this->get_global_query( $parsed_block )
 		);
 
@@ -491,7 +493,7 @@ private function get_queries_by_applied_filters() {
 	 * @param array $parsed_block The Product Query that being rendered.
 	 * @return array
 	 */
-	private function get_queries_by_attributes( $parsed_block ) {
+	private function get_queries_by_custom_attributes( $parsed_block ) {
 		$query            = $parsed_block['attrs']['query'];
 		$on_sale_enabled  = isset( $query['__woocommerceOnSale'] ) && true === $query['__woocommerceOnSale'];
 		$attributes_query = isset( $query['__woocommerceAttributes'] ) ? $this->get_product_attributes_query( $query['__woocommerceAttributes'] ) : array();
@@ -625,7 +627,6 @@ function( $stock_status ) {
 					'key'      => '_stock_status',
 					'value'    => $filtered_stock_status_values,
 					'operator' => 'IN',
-
 				),
 			),
 		);
@@ -814,4 +815,65 @@ function( $rating ) use ( $product_visibility_terms ) {
 		);
 	}
 
+
+	/**
+	 * Return a query to filter products by taxonomies (product categories, product tags, etc.)
+	 *
+	 * For example:
+	 * User could provide "Product Categories" using "Filters" ToolsPanel available in Inspector Controls.
+	 * We use this function to extract it's query from $tax_query.
+	 *
+	 * For example, this is how the query for product categories will look like in $tax_query array:
+	 * Array
+	 *    (
+	 *        [taxonomy] => product_cat
+	 *        [terms] => Array
+	 *            (
+	 *                [0] => 36
+	 *            )
+	 *    )
+	 *
+	 * For product categories, taxonomy would be "product_tag"
+	 *
+	 * @param array $query WP_Query.
+	 * @return array Query to filter products by taxonomies.
+	 */
+	private function get_filter_by_taxonomies_query( $query ): array {
+		if ( ! isset( $query['tax_query'] ) || ! is_array( $query['tax_query'] ) ) {
+			return [];
+		}
+
+		$tax_query = $query['tax_query'];
+		/**
+		 * Get an array of taxonomy names associated with the "product" post type because
+		 * we also want to include custom taxonomies associated with the "product" post type.
+		 */
+		$product_taxonomies = get_taxonomies( array( 'object_type' => array( 'product' ) ), 'names' );
+		$result             = array_filter(
+			$tax_query,
+			function( $item ) use ( $product_taxonomies ) {
+				return isset( $item['taxonomy'] ) && in_array( $item['taxonomy'], $product_taxonomies, true );
+			}
+		);
+
+		return ! empty( $result ) ? [ 'tax_query' => $result ] : [];
+	}
+
+	/**
+	 * Returns the keyword filter from the given query.
+	 *
+	 * @param WP_Query $query The query to extract the keyword filter from.
+	 * @return array The keyword filter, or an empty array if none is found.
+	 */
+	private function get_filter_by_keyword_query( $query ): array {
+		if ( ! is_array( $query ) ) {
+			return [];
+		}
+
+		if ( isset( $query['s'] ) ) {
+			return [ 's' => $query['s'] ];
+		}
+
+		return [];
+	}
 }