<?php

/**

 * Server-side rendering of the `core/image` block.

 *

 * @package WordPress

 */

/**

 * Renders the `core/image` block on the server,

 * adding a data-id attribute to the element if core/gallery has added on pre-render.

 *

 * @param  array  $attributes The block attributes.

 * @param  string $content    The block content.

 * @return string Returns the block content with the data-id attribute added.

 */

function render_block_core_image( $attributes, $content ) {

	if ( isset( $attributes['data-id'] ) ) {

		// Add the data-id="$id" attribute to the img element

		// to provide backwards compatibility for the Gallery Block,

		// which now wraps Image Blocks within innerBlocks.

		// The data-id attribute is added in a core/gallery `render_block_data` hook.

		$data_id_attribute = 'data-id="' . esc_attr( $attributes['data-id'] ) . '"';

		if ( false === strpos( $content, $data_id_attribute ) ) {

			$content = str_replace( '<img', '<img ' . $data_id_attribute . ' ', $content );

		}

	}

	return $content;

}

/**

 * Registers the `core/image` block on server.

 */

function register_block_core_image() {

	register_block_type_from_metadata(

		__DIR__ . '/image',

		array(

			'render_callback' => 'render_block_core_image',

		)

	);

}

add_action( 'init', 'register_block_core_image' );