<?php

/**

 * Block Renderer REST API: WP_REST_Block_Renderer_Controller class

 *

 * @package WordPress

 * @subpackage REST_API

 * @since 5.0.0

 */

/**

 * Controller which provides REST endpoint for rendering a block.

 *

 * @since 5.0.0

 *

 * @see WP_REST_Controller

 */

class WP_REST_Block_Renderer_Controller extends WP_REST_Controller {

	/**

	 * Constructs the controller.

	 *

	 * @since 5.0.0

	 */

	public function __construct() {

		$this->namespace = 'wp/v2';

		$this->rest_base = 'block-renderer';

	}

	/**

	 * Registers the necessary REST API routes, one for each dynamic block.

	 *

	 * @since 5.0.0

	 *

	 * @see register_rest_route()

	 */

	public function register_routes() {

		register_rest_route(

			$this->namespace,

			'/' . $this->rest_base . '/(?P<name>[a-z0-9-]+/[a-z0-9-]+)',

			array(

				'args'   => array(

					'name' => array(

						'description' => __( 'Unique registered name for the block.' ),

						'type'        => 'string',

					),

				),

				array(

					'methods'             => array( WP_REST_Server::READABLE, WP_REST_Server::CREATABLE ),

					'callback'            => array( $this, 'get_item' ),

					'permission_callback' => array( $this, 'get_item_permissions_check' ),

					'args'                => array(

						'context'    => $this->get_context_param( array( 'default' => 'view' ) ),

						'attributes' => array(

							'description'       => __( 'Attributes for the block.' ),

							'type'              => 'object',

							'default'           => array(),

							'validate_callback' => static function ( $value, $request ) {

								$block = WP_Block_Type_Registry::get_instance()->get_registered( $request['name'] );

								if ( ! $block ) {

									// This will get rejected in ::get_item().

									return true;

								}

								$schema = array(

									'type'                 => 'object',

									'properties'           => $block->get_attributes(),

									'additionalProperties' => false,

								);

								return rest_validate_value_from_schema( $value, $schema );

							},

							'sanitize_callback' => static function ( $value, $request ) {

								$block = WP_Block_Type_Registry::get_instance()->get_registered( $request['name'] );

								if ( ! $block ) {

									// This will get rejected in ::get_item().

									return true;

								}

								$schema = array(

									'type'                 => 'object',

									'properties'           => $block->get_attributes(),

									'additionalProperties' => false,

								);

								return rest_sanitize_value_from_schema( $value, $schema );

							},

						),

						'post_id'    => array(

							'description' => __( 'ID of the post context.' ),

							'type'        => 'integer',

						),

					),

				),

				'schema' => array( $this, 'get_public_item_schema' ),

			)

		);

	}

	/**

	 * Checks if a given request has access to read blocks.

	 *

	 * @since 5.0.0

	 *

	 * @global WP_Post $post Global post object.

	 *

	 * @param WP_REST_Request $request Request.

	 * @return true|WP_Error True if the request has read access, WP_Error object otherwise.

	 */

	public function get_item_permissions_check( $request ) {

		global $post;

		$post_id = isset( $request['post_id'] ) ? (int) $request['post_id'] : 0;

		if ( $post_id > 0 ) {

			$post = get_post( $post_id );

			if ( ! $post || ! current_user_can( 'edit_post', $post->ID ) ) {

				return new WP_Error(

					'block_cannot_read',

					__( 'Sorry, you are not allowed to read blocks of this post.' ),

					array(

						'status' => rest_authorization_required_code(),

					)

				);

			}

		} else {

			if ( ! current_user_can( 'edit_posts' ) ) {

				return new WP_Error(

					'block_cannot_read',

					__( 'Sorry, you are not allowed to read blocks as this user.' ),

					array(

						'status' => rest_authorization_required_code(),

					)

				);

			}

		}

		return true;

	}

	/**

	 * Returns block output from block's registered render_callback.

	 *

	 * @since 5.0.0

	 *

	 * @global WP_Post $post Global post object.

	 *

	 * @param WP_REST_Request $request Full details about the request.

	 * @return WP_REST_Response|WP_Error Response object on success, or WP_Error object on failure.

	 */

	public function get_item( $request ) {

		global $post;

		$post_id = isset( $request['post_id'] ) ? (int) $request['post_id'] : 0;

		if ( $post_id > 0 ) {

			$post = get_post( $post_id );

			// Set up postdata since this will be needed if post_id was set.

			setup_postdata( $post );

		}

		$registry   = WP_Block_Type_Registry::get_instance();

		$registered = $registry->get_registered( $request['name'] );

		if ( null === $registered || ! $registered->is_dynamic() ) {

			return new WP_Error(

				'block_invalid',

				__( 'Invalid block.' ),

				array(

					'status' => 404,

				)

			);

		}

		$attributes = $request->get_param( 'attributes' );

		// Create an array representation simulating the output of parse_blocks.

		$block = array(

			'blockName'    => $request['name'],

			'attrs'        => $attributes,

			'innerHTML'    => '',

			'innerContent' => array(),

		);

		// Render using render_block to ensure all relevant filters are used.

		$data = array(

			'rendered' => render_block( $block ),

		);

		return rest_ensure_response( $data );

	}

	/**

	 * Retrieves block's output schema, conforming to JSON Schema.

	 *

	 * @since 5.0.0

	 *

	 * @return array Item schema data.

	 */

	public function get_item_schema() {

		if ( $this->schema ) {

			return $this->schema;

		}

		$this->schema = array(

			'$schema'    => 'http://json-schema.org/schema#',

			'title'      => 'rendered-block',

			'type'       => 'object',

			'properties' => array(

				'rendered' => array(

					'description' => __( 'The rendered block.' ),

					'type'        => 'string',

					'required'    => true,

					'context'     => array( 'edit' ),

				),

			),

		);

		return $this->schema;

	}

}