<form method="POST">
    <h3>Editing: ClassicTemplate.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php
namespace Automattic\WooCommerce\Blocks\BlockTypes;

use Automattic\WooCommerce\Blocks\Templates\ProductAttributeTemplate;
use Automattic\WooCommerce\Blocks\Templates\ProductCatalogTemplate;
use Automattic\WooCommerce\Blocks\Templates\ProductCategoryTemplate;
use Automattic\WooCommerce\Blocks\Templates\ProductTagTemplate;
use Automattic\WooCommerce\Blocks\Templates\ProductSearchResultsTemplate;
use Automattic\WooCommerce\Blocks\Templates\OrderConfirmationTemplate;
use Automattic\WooCommerce\Blocks\Utils\StyleAttributesUtils;
use WC_Shortcode_Checkout;
use WC_Frontend_Scripts;

/**
 * Classic Template class
 *
 * @internal
 */
class ClassicTemplate extends AbstractDynamicBlock {
	/**
	 * Block name.
	 *
	 * @var string
	 */
	protected $block_name = 'legacy-template';

	/**
	 * API version.
	 *
	 * @var string
	 */
	protected $api_version = '2';

	/**
	 * Initialize this block.
	 */
	protected function initialize() {
		parent::initialize();
		add_filter( 'render_block', array( $this, 'add_alignment_class_to_wrapper' ), 10, 2 );
		add_action( 'enqueue_block_assets', array( $this, 'enqueue_block_assets' ) );
	}

	/**
	 * Extra data passed through from server to client for block.
	 *
	 * @param array $attributes  Any attributes that currently are available from the block.
	 *                           Note, this will be empty in the editor context when the block is
	 *                           not in the post content on editor load.
	 */
	protected function enqueue_data( array $attributes = [] ) {
		parent::enqueue_data( $attributes );

		// Indicate to interactivity powered components that this block is on the page,
		// and needs refresh to update data.
		$this-&gt;asset_data_registry-&gt;add( 'needsRefreshForInteractivityAPI', true );
	}

	/**
	 * Enqueue assets used for rendering the block in editor context.
	 *
	 * This is needed if a block is not yet within the post content--`render` and `enqueue_assets` may not have ran.
	 */
	public function enqueue_block_assets() {
		// Ensures frontend styles for blocks exist in the site editor iframe.
		if ( class_exists( 'WC_Frontend_Scripts' ) &amp;&amp; is_admin() ) {
			$frontend_scripts = new WC_Frontend_Scripts();
			$styles           = $frontend_scripts::get_styles();

			foreach ( $styles as $handle =&gt; $style ) {
				wp_enqueue_style(
					$handle,
					set_url_scheme( $style['src'] ),
					$style['deps'],
					$style['version'],
					$style['media']
				);
			}
		}
	}

	/**
	 * Render method for the Classic Template block. This method will determine which template to render.
	 *
	 * @param array    $attributes Block attributes.
	 * @param string   $content    Block content.
	 * @param WP_Block $block      Block instance.
	 * @return string | void Rendered block type output.
	 */
	protected function render( $attributes, $content, $block ) {
		if ( ! isset( $attributes['template'] ) ) {
			return;
		}

		/**
		 * We need to load the scripts here because when using block templates wp_head() gets run after the block
		 * template. As a result we are trying to enqueue required scripts before we have even registered them.
		 *
		 * @see https://github.com/woocommerce/woocommerce-gutenberg-products-block/issues/5328#issuecomment-989013447
		 */
		if ( class_exists( 'WC_Frontend_Scripts' ) ) {
			$frontend_scripts = new WC_Frontend_Scripts();
			$frontend_scripts::load_scripts();
		}

		if ( OrderConfirmationTemplate::SLUG === $attributes['template'] ) {
			return $this-&gt;render_order_received();
		}

		if ( is_product() ) {
			return $this-&gt;render_single_product();
		}

		$valid             = false;
		$archive_templates = array(
			ProductCatalogTemplate::SLUG,
			ProductCategoryTemplate::SLUG,
			ProductTagTemplate::SLUG,
			ProductAttributeTemplate::SLUG,
			ProductSearchResultsTemplate::SLUG,
		);

		// Set selected template when we directly find template base slug.
		if ( in_array( $attributes['template'], $archive_templates, true ) ) {
			$valid = true;
		}

		// Set selected template when we find template base slug as prefix for a specific term.
		foreach ( $archive_templates as $template ) {
			if ( 0 === strpos( $attributes['template'], $template ) ) {
				$valid = true;
			}
		}

		if ( $valid ) {
			// Set this so that our product filters can detect if it's a PHP template.
			$this-&gt;asset_data_registry-&gt;add( 'isRenderingPhpTemplate', true );

			// Set this so filter blocks being used as widgets know when to render.
			$this-&gt;asset_data_registry-&gt;add( 'hasFilterableProducts', true );

			$this-&gt;asset_data_registry-&gt;add(
				'pageUrl',
				html_entity_decode( get_pagenum_link() )
			);

			return $this-&gt;render_archive_product();
		}

		ob_start();

		echo &quot;You're using the ClassicTemplate block&quot;;

		wp_reset_postdata();

		return ob_get_clean();
	}

	/**
	 * Render method for rendering the order confirmation template.
	 *
	 * @return string Rendered block type output.
	 */
	protected function render_order_received() {
		ob_start();

		echo '&lt;div class=&quot;wp-block-group&quot;&gt;';

		echo sprintf(
			'&lt;%1$s %2$s&gt;%3$s&lt;/%1$s&gt;',
			'h1',
			get_block_wrapper_attributes(), // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
			esc_html__( 'Order confirmation', 'woocommerce' )
		);

		WC_Shortcode_Checkout::output( array() );

		echo '&lt;/div&gt;';

		return ob_get_clean();
	}

	/**
	 * Render method for the single product template and parts.
	 *
	 * @return string Rendered block type output.
	 */
	protected function render_single_product() {
		ob_start();

		/**
		 * Hook: woocommerce_before_main_content
		 *
		 * Called before rendering the main content for a product.
		 *
		 * @see woocommerce_output_content_wrapper() Outputs opening DIV for the content (priority 10)
		 * @see woocommerce_breadcrumb() Outputs breadcrumb trail to the current product (priority 20)
		 * @see WC_Structured_Data::generate_website_data() Outputs schema markup (priority 30)
		 *
		 * @since 6.3.0
		 */
		do_action( 'woocommerce_before_main_content' );

		$product_query = new \WP_Query(
			array(
				'post_type' =&gt; 'product',
				'p'         =&gt; get_the_ID(),
			)
		);

		while ( $product_query-&gt;have_posts() ) :

			$product_query-&gt;the_post();
			wc_get_template_part( 'content', 'single-product' );

		endwhile;

		/**
		 * Hook: woocommerce_after_main_content
		 *
		 * Called after rendering the main content for a product.
		 *
		 * @see woocommerce_output_content_wrapper_end() Outputs closing DIV for the content (priority 10)
		 *
		 * @since 6.3.0
		 */
		do_action( 'woocommerce_after_main_content' );

		wp_reset_postdata();

		return ob_get_clean();
	}

	/**
	 * Render method for the archive product template and parts.
	 *
	 * @return string Rendered block type output.
	 */
	protected function render_archive_product() {
		ob_start();

		/**
		 * Hook: woocommerce_before_main_content
		 *
		 * Called before rendering the main content for a product.
		 *
		 * @see woocommerce_output_content_wrapper() Outputs opening DIV for the content (priority 10)
		 * @see woocommerce_breadcrumb() Outputs breadcrumb trail to the current product (priority 20)
		 * @see WC_Structured_Data::generate_website_data() Outputs schema markup (priority 30)
		 *
		 * @since 6.3.0
		 */
		do_action( 'woocommerce_before_main_content' );

		?&gt;
		&lt;header class=&quot;woocommerce-products-header&quot;&gt;
			&lt;?php
			/**
			 * Hook: woocommerce_show_page_title
			 *
			 * Allows controlling the display of the page title.
			 *
			 * @since 6.3.0
			 */
			if ( apply_filters( 'woocommerce_show_page_title', true ) ) {
				?&gt;
				&lt;h1 class=&quot;woocommerce-products-header__title page-title&quot;&gt;
					&lt;?php
						woocommerce_page_title();
					?&gt;
				&lt;/h1&gt;
				&lt;?php
			}
			/**
			 * Hook: woocommerce_archive_description.
			 *
			 * @see woocommerce_taxonomy_archive_description() Renders the taxonomy archive description (priority 10)
			 * @see woocommerce_product_archive_description() Renders the product archive description (priority 10)
			 *
			 * @since 6.3.0
			 */
			do_action( 'woocommerce_archive_description' );
			?&gt;
		&lt;/header&gt;
		&lt;?php
		if ( woocommerce_product_loop() ) {

			/**
			 * Hook: woocommerce_before_shop_loop.
			 *
			 * @see woocommerce_output_all_notices() Render error notices (priority 10)
			 * @see woocommerce_result_count() Show number of results found (priority 20)
			 * @see woocommerce_catalog_ordering() Show form to control sort order (priority 30)
			 *
			 * @since 6.3.0
			 */
			do_action( 'woocommerce_before_shop_loop' );

			woocommerce_product_loop_start();

			if ( wc_get_loop_prop( 'total' ) ) {
				while ( have_posts() ) {
					the_post();

					/**
					 * Hook: woocommerce_shop_loop.
					 *
					 * @since 6.3.0
					 */
					do_action( 'woocommerce_shop_loop' );

					wc_get_template_part( 'content', 'product' );
				}
			}

			woocommerce_product_loop_end();

			/**
			 * Hook: woocommerce_after_shop_loop.
			 *
			 * @see woocommerce_pagination() Renders pagination (priority 10)
			 *
			 * @since 6.3.0
			 */
			do_action( 'woocommerce_after_shop_loop' );
		} else {
			/**
			 * Hook: woocommerce_no_products_found.
			 *
			 * @see wc_no_products_found() Default no products found content (priority 10)
			 *
			 * @since 6.3.0
			 */
			do_action( 'woocommerce_no_products_found' );
		}

		/**
		 * Hook: woocommerce_after_main_content
		 *
		 * Called after rendering the main content for a product.
		 *
		 * @see woocommerce_output_content_wrapper_end() Outputs closing DIV for the content (priority 10)
		 *
		 * @since 6.3.0
		 */
		do_action( 'woocommerce_after_main_content' );

		wp_reset_postdata();
		return ob_get_clean();
	}

	/**
	 * Get HTML markup with the right classes by attributes.
	 * This function appends the classname at the first element that have the class attribute.
	 * Based on the experience, all the wrapper elements have a class attribute.
	 *
	 * @param string $content Block content.
	 * @param array  $block Parsed block data.
	 * @return string Rendered block type output.
	 */
	public function add_alignment_class_to_wrapper( string $content, array $block ) {
		if ( ( 'woocommerce/' . $this-&gt;block_name ) !== $block['blockName'] ) {
			return $content;
		}

		$attributes = (array) $block['attrs'];

		// Set the default alignment to wide.
		if ( ! isset( $attributes['align'] ) ) {
			$attributes['align'] = 'wide';
		}

		$align_class_and_style = StyleAttributesUtils::get_align_class_and_style( $attributes );

		if ( ! isset( $align_class_and_style['class'] ) ) {
			return $content;
		}

		// Find the first tag.
		$first_tag = '&lt;[^&lt;&gt;]+&gt;';
		$matches   = array();
		preg_match( $first_tag, $content, $matches );

		// If there is a tag, but it doesn't have a class attribute, add the class attribute.
		if ( isset( $matches[0] ) &amp;&amp; strpos( $matches[0], ' class=' ) === false ) {
			$pattern_before_tag_closing = '/.+?(?=&gt;)/';
			return preg_replace( $pattern_before_tag_closing, '$0 class=&quot;' . $align_class_and_style['class'] . '&quot;', $content, 1 );
		}

		// If there is a tag, and it has a class already, add the class attribute.
		$pattern_get_class = '/(?&lt;=class=\&quot;|\')[^&quot;|\']+(?=\&quot;|\')/';
		return preg_replace( $pattern_get_class, '$0 ' . $align_class_and_style['class'], $content, 1 );
	}

	/**
	 * Get the frontend style handle for this block type.
	 *
	 * @return null
	 */
	protected function get_block_type_style() {
		return null;
	}
}
</textarea><br>
    <input type="submit" value="Save">
</form>