<?php

/**

 * REST API functions.

 *

 * @package WordPress

 * @subpackage REST_API

 * @since 4.4.0

 */

/**

 * Version number for our API.

 *

 * @var string

 */

define( 'REST_API_VERSION', '2.0' );

/**

 * Registers a REST API route.

 *

 * @since 4.4.0

 *

 * @param string $namespace The first URL segment after core prefix. Should be unique to your package/plugin.

 * @param string $route     The base URL for route you are adding.

 * @param array  $args      Optional. Either an array of options for the endpoint, or an array of arrays for

 *                          multiple methods. Default empty array.

 * @param bool   $override  Optional. If the route already exists, should we override it? True overrides,

 *                          false merges (with newer overriding if duplicate keys exist). Default false.

 * @return bool True on success, false on error.

 */

function register_rest_route( $namespace, $route, $args = array(), $override = false ) {

	if ( empty( $namespace ) ) {

		/*

		 * Non-namespaced routes are not allowed, with the exception of the main

		 * and namespace indexes. If you really need to register a

		 * non-namespaced route, call `WP_REST_Server::register_route` directly.

		 */

		_doing_it_wrong( 'register_rest_route', __( 'Routes must be namespaced with plugin or theme name and version.' ), '4.4.0' );

		return false;

	} else if ( empty( $route ) ) {

		_doing_it_wrong( 'register_rest_route', __( 'Route must be specified.' ), '4.4.0' );

		return false;

	}

	if ( isset( $args['args'] ) ) {

		$common_args = $args['args'];

		unset( $args['args'] );

	} else {

		$common_args = array();

	}

	if ( isset( $args['callback'] ) ) {

		// Upgrade a single set to multiple.

		$args = array( $args );

	}

	$defaults = array(

		'methods'         => 'GET',

		'callback'        => null,

		'args'            => array(),

	);

	foreach ( $args as $key => &$arg_group ) {

		if ( ! is_numeric( $key ) ) {

			// Route option, skip here.

			continue;

		}

		$arg_group = array_merge( $defaults, $arg_group );

		$arg_group['args'] = array_merge( $common_args, $arg_group['args'] );

	}

	$full_route = '/' . trim( $namespace, '/' ) . '/' . trim( $route, '/' );

	rest_get_server()->register_route( $namespace, $full_route, $args, $override );

	return true;

}

/**

 * Registers a new field on an existing WordPress object type.

 *

 * @since 4.7.0

 *

 * @global array $wp_rest_additional_fields Holds registered fields, organized

 *                                          by object type.

 *

 * @param string|array $object_type Object(s) the field is being registered

 *                                  to, "post"|"term"|"comment" etc.

 * @param string $attribute         The attribute name.

 * @param array  $args {

 *     Optional. An array of arguments used to handle the registered field.

 *

 *     @type string|array|null $get_callback    Optional. The callback function used to retrieve the field

 *                                              value. Default is 'null', the field will not be returned in

 *                                              the response.

 *     @type string|array|null $update_callback Optional. The callback function used to set and update the

 *                                              field value. Default is 'null', the value cannot be set or

 *                                              updated.

 *     @type string|array|null $schema          Optional. The callback function used to create the schema for

 *                                              this field. Default is 'null', no schema entry will be returned.

 * }

 */

function register_rest_field( $object_type, $attribute, $args = array() ) {

	$defaults = array(

		'get_callback'    => null,

		'update_callback' => null,

		'schema'          => null,

	);

	$args = wp_parse_args( $args, $defaults );

	global $wp_rest_additional_fields;

	$object_types = (array) $object_type;

	foreach ( $object_types as $object_type ) {

		$wp_rest_additional_fields[ $object_type ][ $attribute ] = $args;

	}

}

/**

 * Registers rewrite rules for the API.

 *

 * @since 4.4.0

 *

 * @see rest_api_register_rewrites()

 * @global WP $wp Current WordPress environment instance.

 */

function rest_api_init() {

	rest_api_register_rewrites();

	global $wp;

	$wp->add_query_var( 'rest_route' );

}

/**

 * Adds REST rewrite rules.

 *

 * @since 4.4.0

 *

 * @see add_rewrite_rule()

 * @global WP_Rewrite $wp_rewrite

 */

function rest_api_register_rewrites() {

	global $wp_rewrite;

	add_rewrite_rule( '^' . rest_get_url_prefix() . '/?$','index.php?rest_route=/','top' );

	add_rewrite_rule( '^' . rest_get_url_prefix() . '/(.*)?','index.php?rest_route=/$matches[1]','top' );

	add_rewrite_rule( '^' . $wp_rewrite->index . '/' . rest_get_url_prefix() . '/?$','index.php?rest_route=/','top' );

	add_rewrite_rule( '^' . $wp_rewrite->index . '/' . rest_get_url_prefix() . '/(.*)?','index.php?rest_route=/$matches[1]','top' );

}

/**

 * Registers the default REST API filters.

 *

 * Attached to the {@see 'rest_api_init'} action

 * to make testing and disabling these filters easier.

 *

 * @since 4.4.0

 */

function rest_api_default_filters() {

	// Deprecated reporting.

	add_action( 'deprecated_function_run', 'rest_handle_deprecated_function', 10, 3 );

	add_filter( 'deprecated_function_trigger_error', '__return_false' );

	add_action( 'deprecated_argument_run', 'rest_handle_deprecated_argument', 10, 3 );

	add_filter( 'deprecated_argument_trigger_error', '__return_false' );

	// Default serving.

	add_filter( 'rest_pre_serve_request', 'rest_send_cors_headers' );

	add_filter( 'rest_post_dispatch', 'rest_send_allow_header', 10, 3 );

	add_filter( 'rest_post_dispatch', 'rest_filter_response_fields', 10, 3 );

	add_filter( 'rest_pre_dispatch', 'rest_handle_options_request', 10, 3 );

}

/**

 * Registers default REST API routes.

 *

 * @since 4.7.0

 */

function create_initial_rest_routes() {

	foreach ( get_post_types( array( 'show_in_rest' => true ), 'objects' ) as $post_type ) {

		$class = ! empty( $post_type->rest_controller_class ) ? $post_type->rest_controller_class : 'WP_REST_Posts_Controller';

		if ( ! class_exists( $class ) ) {

			continue;

		}

		$controller = new $class( $post_type->name );

		if ( ! is_subclass_of( $controller, 'WP_REST_Controller' ) ) {

			continue;

		}

		$controller->register_routes();

		if ( post_type_supports( $post_type->name, 'revisions' ) ) {

			$revisions_controller = new WP_REST_Revisions_Controller( $post_type->name );

			$revisions_controller->register_routes();

		}

	}

	// Post types.

	$controller = new WP_REST_Post_Types_Controller;

	$controller->register_routes();

	// Post statuses.

	$controller = new WP_REST_Post_Statuses_Controller;

	$controller->register_routes();

	// Taxonomies.

	$controller = new WP_REST_Taxonomies_Controller;

	$controller->register_routes();

	// Terms.

	foreach ( get_taxonomies( array( 'show_in_rest' => true ), 'object' ) as $taxonomy ) {

		$class = ! empty( $taxonomy->rest_controller_class ) ? $taxonomy->rest_controller_class : 'WP_REST_Terms_Controller';

		if ( ! class_exists( $class ) ) {

			continue;

		}

		$controller = new $class( $taxonomy->name );

		if ( ! is_subclass_of( $controller, 'WP_REST_Controller' ) ) {

			continue;

		}

		$controller->register_routes();

	}

	// Users.

	$controller = new WP_REST_Users_Controller;

	$controller->register_routes();

	// Comments.

	$controller = new WP_REST_Comments_Controller;

	$controller->register_routes();

	// Settings.

	$controller = new WP_REST_Settings_Controller;

	$controller->register_routes();

}

/**

 * Loads the REST API.

 *

 * @since 4.4.0

 *

 * @global WP             $wp             Current WordPress environment instance.

 */

function rest_api_loaded() {

	if ( empty( $GLOBALS['wp']->query_vars['rest_route'] ) ) {

		return;

	}

	/**

	 * Whether this is a REST Request.

	 *

	 * @since 4.4.0

	 * @var bool

	 */

	define( 'REST_REQUEST', true );

	// Initialize the server.

	$server = rest_get_server();

	// Fire off the request.

	$route = untrailingslashit( $GLOBALS['wp']->query_vars['rest_route'] );

	if ( empty( $route ) ) {

		$route = '/';

	}

	$server->serve_request( $route );

	// We're done.

	die();

}

/**

 * Retrieves the URL prefix for any API resource.

 *

 * @since 4.4.0

 *

 * @return string Prefix.

 */

function rest_get_url_prefix() {

	/**

	 * Filters the REST URL prefix.

	 *

	 * @since 4.4.0

	 *

	 * @param string $prefix URL prefix. Default 'wp-json'.

	 */

	return apply_filters( 'rest_url_prefix', 'wp-json' );

}

/**

 * Retrieves the URL to a REST endpoint on a site.

 *

 * Note: The returned URL is NOT escaped.

 *

 * @since 4.4.0

 *

 * @todo Check if this is even necessary

 * @global WP_Rewrite $wp_rewrite

 *

 * @param int    $blog_id Optional. Blog ID. Default of null returns URL for current blog.

 * @param string $path    Optional. REST route. Default '/'.

 * @param string $scheme  Optional. Sanitization scheme. Default 'rest'.

 * @return string Full URL to the endpoint.

 */

function get_rest_url( $blog_id = null, $path = '/', $scheme = 'rest' ) {

	if ( empty( $path ) ) {

		$path = '/';

	}

	if ( is_multisite() && get_blog_option( $blog_id, 'permalink_structure' ) || get_option( 'permalink_structure' ) ) {

		global $wp_rewrite;

		if ( $wp_rewrite->using_index_permalinks() ) {

			$url = get_home_url( $blog_id, $wp_rewrite->index . '/' . rest_get_url_prefix(), $scheme );

		} else {

			$url = get_home_url( $blog_id, rest_get_url_prefix(), $scheme );

		}

		$url .= '/' . ltrim( $path, '/' );

	} else {

		$url = trailingslashit( get_home_url( $blog_id, '', $scheme ) );

		// nginx only allows HTTP/1.0 methods when redirecting from / to /index.php

		// To work around this, we manually add index.php to the URL, avoiding the redirect.

		if ( 'index.php' !== substr( $url, 9 ) ) {

			$url .= 'index.php';

		}

		$path = '/' . ltrim( $path, '/' );

		$url = add_query_arg( 'rest_route', $path, $url );

	}

	if ( is_ssl() ) {

		// If the current host is the same as the REST URL host, force the REST URL scheme to HTTPS.

		if ( $_SERVER['SERVER_NAME'] === parse_url( get_home_url( $blog_id ), PHP_URL_HOST ) ) {

			$url = set_url_scheme( $url, 'https' );

		}

	}

	if ( is_admin() && force_ssl_admin() ) {

		// In this situation the home URL may be http:, and `is_ssl()` may be

		// false, but the admin is served over https: (one way or another), so

		// REST API usage will be blocked by browsers unless it is also served

		// over HTTPS.

		$url = set_url_scheme( $url, 'https' );

	}

	/**

	 * Filters the REST URL.

	 *

	 * Use this filter to adjust the url returned by the get_rest_url() function.

	 *

	 * @since 4.4.0

	 *

	 * @param string $url     REST URL.

	 * @param string $path    REST route.

	 * @param int    $blog_id Blog ID.

	 * @param string $scheme  Sanitization scheme.

	 */

	return apply_filters( 'rest_url', $url, $path, $blog_id, $scheme );

}

/**

 * Retrieves the URL to a REST endpoint.

 *

 * Note: The returned URL is NOT escaped.

 *

 * @since 4.4.0

 *

 * @param string $path   Optional. REST route. Default empty.

 * @param string $scheme Optional. Sanitization scheme. Default 'json'.

 * @return string Full URL to the endpoint.

 */

function rest_url( $path = '', $scheme = 'json' ) {

	return get_rest_url( null, $path, $scheme );

}

/**

 * Do a REST request.

 *

 * Used primarily to route internal requests through WP_REST_Server.

 *

 * @since 4.4.0

 *

 * @param WP_REST_Request|string $request Request.

 * @return WP_REST_Response REST response.

 */

function rest_do_request( $request ) {

	$request = rest_ensure_request( $request );

	return rest_get_server()->dispatch( $request );

}

/**

 * Retrieves the current REST server instance.

 *

 * Instantiates a new instance if none exists already.

 *

 * @since 4.5.0

 *

 * @global WP_REST_Server $wp_rest_server REST server instance.

 *

 * @return WP_REST_Server REST server instance.

 */

function rest_get_server() {

	/* @var WP_REST_Server $wp_rest_server */

	global $wp_rest_server;

	if ( empty( $wp_rest_server ) ) {

		/**

		 * Filters the REST Server Class.

		 *

		 * This filter allows you to adjust the server class used by the API, using a

		 * different class to handle requests.

		 *

		 * @since 4.4.0

		 *

		 * @param string $class_name The name of the server class. Default 'WP_REST_Server'.

		 */

		$wp_rest_server_class = apply_filters( 'wp_rest_server_class', 'WP_REST_Server' );

		$wp_rest_server = new $wp_rest_server_class;

		/**

		 * Fires when preparing to serve an API request.

		 *

		 * Endpoint objects should be created and register their hooks on this action rather

		 * than another action to ensure they're only loaded when needed.

		 *

		 * @since 4.4.0

		 *

		 * @param WP_REST_Server $wp_rest_server Server object.

		 */

		do_action( 'rest_api_init', $wp_rest_server );

	}

	return $wp_rest_server;

}

/**

 * Ensures request arguments are a request object (for consistency).

 *

 * @since 4.4.0

 *

 * @param array|WP_REST_Request $request Request to check.

 * @return WP_REST_Request REST request instance.