<?php

/**

 * REST API: WP_REST_Autosaves_Controller class.

 *

 * @package WordPress

 * @subpackage REST_API

 * @since 5.0.0

 */

/**

 * Core class used to access autosaves via the REST API.

 *

 * @since 5.0.0

 *

 * @see WP_REST_Revisions_Controller

 * @see WP_REST_Controller

 */

class WP_REST_Autosaves_Controller extends WP_REST_Revisions_Controller {

	/**

	 * Parent post type.

	 *

	 * @since 5.0.0

	 * @var string

	 */

	private $parent_post_type;

	/**

	 * Parent post controller.

	 *

	 * @since 5.0.0

	 * @var WP_REST_Controller

	 */

	private $parent_controller;

	/**

	 * Revision controller.

	 *

	 * @since 5.0.0

	 * @var WP_REST_Revisions_Controller

	 */

	private $revisions_controller;

	/**

	 * The base of the parent controller's route.

	 *

	 * @since 5.0.0

	 * @var string

	 */

	private $parent_base;

	/**

	 * Constructor.

	 *

	 * @since 5.0.0

	 *

	 * @param string $parent_post_type Post type of the parent.

	 */

	public function __construct( $parent_post_type ) {

		$this->parent_post_type = $parent_post_type;

		$post_type_object       = get_post_type_object( $parent_post_type );

		$parent_controller      = $post_type_object->get_rest_controller();

		if ( ! $parent_controller ) {

			$parent_controller = new WP_REST_Posts_Controller( $parent_post_type );

		}

		$this->parent_controller = $parent_controller;

		$revisions_controller = $post_type_object->get_revisions_rest_controller();

		if ( ! $revisions_controller ) {

			$revisions_controller = new WP_REST_Revisions_Controller( $parent_post_type );

		}

		$this->revisions_controller = $revisions_controller;

		$this->rest_base            = 'autosaves';

		$this->parent_base          = ! empty( $post_type_object->rest_base ) ? $post_type_object->rest_base : $post_type_object->name;

		$this->namespace            = ! empty( $post_type_object->rest_namespace ) ? $post_type_object->rest_namespace : 'wp/v2';

	}

	/**

	 * Registers the routes for autosaves.

	 *

	 * @since 5.0.0

	 *

	 * @see register_rest_route()

	 */

	public function register_routes() {

		register_rest_route(

			$this->namespace,

			'/' . $this->parent_base . '/(?P<id>[\d]+)/' . $this->rest_base,

			array(

				'args'   => array(

					'parent' => array(

						'description' => __( 'The ID for the parent of the autosave.' ),

						'type'        => 'integer',

					),

				),

				array(

					'methods'             => WP_REST_Server::READABLE,

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

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

					'args'                => $this->get_collection_params(),

				),

				array(

					'methods'             => WP_REST_Server::CREATABLE,

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

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

					'args'                => $this->parent_controller->get_endpoint_args_for_item_schema( WP_REST_Server::EDITABLE ),

				),

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

			)

		);

		register_rest_route(

			$this->namespace,

			'/' . $this->parent_base . '/(?P<parent>[\d]+)/' . $this->rest_base . '/(?P<id>[\d]+)',

			array(

				'args'   => array(

					'parent' => array(

						'description' => __( 'The ID for the parent of the autosave.' ),

						'type'        => 'integer',

					),

					'id'     => array(

						'description' => __( 'The ID for the autosave.' ),

						'type'        => 'integer',

					),

				),

				array(

					'methods'             => WP_REST_Server::READABLE,

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

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

					'args'                => array(

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

					),

				),

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

			)

		);

	}

	/**

	 * Get the parent post.

	 *

	 * @since 5.0.0

	 *

	 * @param int $parent_id Supplied ID.

	 * @return WP_Post|WP_Error Post object if ID is valid, WP_Error otherwise.

	 */

	protected function get_parent( $parent_id ) {

		return $this->revisions_controller->get_parent( $parent_id );

	}

	/**

	 * Checks if a given request has access to get autosaves.

	 *

	 * @since 5.0.0

	 *

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

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

	 */

	public function get_items_permissions_check( $request ) {

		$parent = $this->get_parent( $request['id'] );

		if ( is_wp_error( $parent ) ) {

			return $parent;

		}

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

			return new WP_Error(

				'rest_cannot_read',

				__( 'Sorry, you are not allowed to view autosaves of this post.' ),

				array( 'status' => rest_authorization_required_code() )

			);

		}

		return true;

	}

	/**

	 * Checks if a given request has access to create an autosave revision.

	 *

	 * Autosave revisions inherit permissions from the parent post,

	 * check if the current user has permission to edit the post.

	 *

	 * @since 5.0.0

	 *

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

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

	 */

	public function create_item_permissions_check( $request ) {

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

		if ( empty( $id ) ) {

			return new WP_Error(

				'rest_post_invalid_id',

				__( 'Invalid item ID.' ),

				array( 'status' => 404 )

			);

		}

		return $this->parent_controller->update_item_permissions_check( $request );

	}

	/**

	 * Creates, updates or deletes an autosave revision.

	 *

	 * @since 5.0.0

	 *

	 * @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 create_item( $request ) {

		if ( ! defined( 'WP_RUN_CORE_TESTS' ) && ! defined( 'DOING_AUTOSAVE' ) ) {

			define( 'DOING_AUTOSAVE', true );

		}

		$post = $this->get_parent( $request['id'] );

		if ( is_wp_error( $post ) ) {

			return $post;

		}

		$prepared_post     = $this->parent_controller->prepare_item_for_database( $request );

		$prepared_post->ID = $post->ID;

		$user_id           = get_current_user_id();

		// We need to check post lock to ensure the original author didn't leave their browser tab open.

		if ( ! function_exists( 'wp_check_post_lock' ) ) {

			require_once ABSPATH . 'wp-admin/includes/post.php';

		}

		$post_lock = wp_check_post_lock( $post->ID );

		$is_draft  = 'draft' === $post->post_status || 'auto-draft' === $post->post_status;

		if ( $is_draft && (int) $post->post_author === $user_id && ! $post_lock ) {

			/*

			 * Draft posts for the same author: autosaving updates the post and does not create a revision.

			 * Convert the post object to an array and add slashes, wp_update_post() expects escaped array.

			 */

			$autosave_id = wp_update_post( wp_slash( (array) $prepared_post ), true );

		} else {

			// Non-draft posts: create or update the post autosave. Pass the meta data.

			$autosave_id = $this->create_post_autosave( (array) $prepared_post, (array) $request->get_param( 'meta' ) );

		}

		if ( is_wp_error( $autosave_id ) ) {

			return $autosave_id;

		}

		$autosave = get_post( $autosave_id );

		$request->set_param( 'context', 'edit' );

		$response = $this->prepare_item_for_response( $autosave, $request );

		$response = rest_ensure_response( $response );

		return $response;

	}

	/**

	 * Get the autosave, if the ID is valid.

	 *

	 * @since 5.0.0

	 *

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

	 * @return WP_Post|WP_Error Revision post object if ID is valid, WP_Error otherwise.

	 */

	public function get_item( $request ) {

		$parent_id = (int) $request->get_param( 'parent' );

		if ( $parent_id <= 0 ) {

			return new WP_Error(

				'rest_post_invalid_id',

				__( 'Invalid post parent ID.' ),

				array( 'status' => 404 )

			);

		}

		$autosave = wp_get_post_autosave( $parent_id );

		if ( ! $autosave ) {

			return new WP_Error(

				'rest_post_no_autosave',

				__( 'There is no autosave revision for this post.' ),

				array( 'status' => 404 )

			);

		}

		$response = $this->prepare_item_for_response( $autosave, $request );

		return $response;

	}

	/**

	 * Gets a collection of autosaves using wp_get_post_autosave.

	 *

	 * Contains the user's autosave, for empty if it doesn't exist.

	 *

	 * @since 5.0.0

	 *

	 * @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_items( $request ) {

		$parent = $this->get_parent( $request['id'] );

		if ( is_wp_error( $parent ) ) {

			return $parent;

		}

		$response  = array();

		$parent_id = $parent->ID;

		$revisions = wp_get_post_revisions( $parent_id, array( 'check_enabled' => false ) );

		foreach ( $revisions as $revision ) {

			if ( str_contains( $revision->post_name, "{$parent_id}-autosave" ) ) {

				$data       = $this->prepare_item_for_response( $revision, $request );

				$response[] = $this->prepare_response_for_collection( $data );

			}

		}

		return rest_ensure_response( $response );

	}

	/**

	 * Retrieves the autosave's schema, conforming to JSON Schema.

	 *

	 * @since 5.0.0

	 *

	 * @return array Item schema data.

	 */

	public function get_item_schema() {

		if ( $this->schema ) {

			return $this->add_additional_fields_schema( $this->schema );

		}

		$schema = $this->revisions_controller->get_item_schema();

		$schema['properties']['preview_link'] = array(

			'description' => __( 'Preview link for the post.' ),

			'type'        => 'string',

			'format'      => 'uri',

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

			'readonly'    => true,

		);

		$this->schema = $schema;

		return $this->add_additional_fields_schema( $this->schema );

	}

	/**

	 * Creates autosave for the specified post.

	 *

	 * From wp-admin/post.php.

	 *

	 * @since 5.0.0

	 * @since 6.4.0 The `$meta` parameter was added.

	 *

	 * @param array $post_data Associative array containing the post data.

	 * @param array $meta      Associative array containing the post meta data.

	 * @return mixed The autosave revision ID or WP_Error.

	 */

	public function create_post_autosave( $post_data, array $meta = array() ) {

		$post_id = (int) $post_data['ID'];

		$post    = get_post( $post_id );

		if ( is_wp_error( $post ) ) {

			return $post;

		}

		// Only create an autosave when it is different from the saved post.

		$autosave_is_different = false;

		$new_autosave          = _wp_post_revision_data( $post_data, true );

		foreach ( array_intersect( array_keys( $new_autosave ), array_keys( _wp_post_revision_fields( $post ) ) ) as $field ) {

			if ( normalize_whitespace( $new_autosave[ $field ] ) !== normalize_whitespace( $post->$field ) ) {

				$autosave_is_different = true;

				break;

			}

		}

		// Check if meta values have changed.

		if ( ! empty( $meta ) ) {

			$revisioned_meta_keys = wp_post_revision_meta_keys( $post->post_type );

			foreach ( $revisioned_meta_keys as $meta_key ) {

				// get_metadata_raw is used to avoid retrieving the default value.

				$old_meta = get_metadata_raw( 'post', $post_id, $meta_key, true );

				$new_meta = isset( $meta[ $meta_key ] ) ? $meta[ $meta_key ] : '';

				if ( $new_meta !== $old_meta ) {

					$autosave_is_different = true;

					break;

				}

			}

		}

		$user_id = get_current_user_id();

		// Store one autosave per author. If there is already an autosave, overwrite it.

		$old_autosave = wp_get_post_autosave( $post_id, $user_id );

		if ( ! $autosave_is_different && $old_autosave ) {

			// Nothing to save, return the existing autosave.

			return $old_autosave->ID;

		}

		if ( $old_autosave ) {

			$new_autosave['ID']          = $old_autosave->ID;

			$new_autosave['post_author'] = $user_id;

			/** This filter is documented in wp-admin/post.php */

			do_action( 'wp_creating_autosave', $new_autosave );

			// wp_update_post() expects escaped array.

			$revision_id = wp_update_post( wp_slash( $new_autosave ) );

		} else {

			// Create the new autosave as a special post revision.

			$revision_id = _wp_put_post_revision( $post_data, true );

		}