<?php

/**

 * REST API: WP_REST_Posts_Controller class

 *

 * @package WordPress

 * @subpackage REST_API

 * @since 4.7.0

 */

/**

 * Core class to access posts via the REST API.

 *

 * @since 4.7.0

 *

 * @see WP_REST_Controller

 */

class WP_REST_Posts_Controller extends WP_REST_Controller {

	/**

	 * Post type.

	 *

	 * @since 4.7.0

	 * @var string

	 */

	protected $post_type;

	/**

	 * Instance of a post meta fields object.

	 *

	 * @since 4.7.0

	 * @var WP_REST_Post_Meta_Fields

	 */

	protected $meta;

	/**

	 * Constructor.

	 *

	 * @since 4.7.0

	 *

	 * @param string $post_type Post type.

	 */

	public function __construct( $post_type ) {

		$this->post_type = $post_type;

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

		$obj = get_post_type_object( $post_type );

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

		$this->meta = new WP_REST_Post_Meta_Fields( $this->post_type );

	}

	/**

	 * Registers the routes for the objects of the controller.

	 *

	 * @since 4.7.0

	 *

	 * @see register_rest_route()

	 */

	public function register_routes() {

		register_rest_route( $this->namespace, '/' . $this->rest_base, array(

			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->get_endpoint_args_for_item_schema( WP_REST_Server::CREATABLE ),

			),

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

		) );

		$schema = $this->get_item_schema();

		$get_item_args = array(

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

		);

		if ( isset( $schema['properties']['password'] ) ) {

			$get_item_args['password'] = array(

				'description' => __( 'The password for the post if it is password protected.' ),

				'type'        => 'string',

			);

		}

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

			'args' => array(

				'id' => array(

					'description' => __( 'Unique identifier for the object.' ),

					'type'        => 'integer',

				),

			),

			array(

				'methods'             => WP_REST_Server::READABLE,

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

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

				'args'                => $get_item_args,

			),

			array(

				'methods'             => WP_REST_Server::EDITABLE,

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

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

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

			),

			array(

				'methods'             => WP_REST_Server::DELETABLE,

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

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

				'args'                => array(

					'force' => array(

						'type'        => 'boolean',

						'default'     => false,

						'description' => __( 'Whether to bypass trash and force deletion.' ),

					),

				),

			),

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

		) );

	}

	/**

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

	 *

	 * @since 4.7.0

	 *

	 * @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 ) {

		$post_type = get_post_type_object( $this->post_type );

		if ( 'edit' === $request['context'] && ! current_user_can( $post_type->cap->edit_posts ) ) {

			return new WP_Error( 'rest_forbidden_context', __( 'Sorry, you are not allowed to edit posts in this post type.' ), array( 'status' => rest_authorization_required_code() ) );

		}

		return true;

	}

	/**

	 * Retrieves a collection of posts.

	 *

	 * @since 4.7.0

	 *

	 * @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 ) {

		// Ensure a search string is set in case the orderby is set to 'relevance'.

		if ( ! empty( $request['orderby'] ) && 'relevance' === $request['orderby'] && empty( $request['search'] ) ) {

			return new WP_Error( 'rest_no_search_term_defined', __( 'You need to define a search term to order by relevance.' ), array( 'status' => 400 ) );

		}

		// Ensure an include parameter is set in case the orderby is set to 'include'.

		if ( ! empty( $request['orderby'] ) && 'include' === $request['orderby'] && empty( $request['include'] ) ) {

			return new WP_Error( 'rest_orderby_include_missing_include', __( 'You need to define an include parameter to order by include.' ), array( 'status' => 400 ) );

		}

		// Retrieve the list of registered collection query parameters.

		$registered = $this->get_collection_params();

		$args = array();

		/*

		 * This array defines mappings between public API query parameters whose

		 * values are accepted as-passed, and their internal WP_Query parameter

		 * name equivalents (some are the same). Only values which are also

		 * present in $registered will be set.

		 */

		$parameter_mappings = array(

			'author'         => 'author__in',

			'author_exclude' => 'author__not_in',

			'exclude'        => 'post__not_in',

			'include'        => 'post__in',

			'menu_order'     => 'menu_order',

			'offset'         => 'offset',

			'order'          => 'order',

			'orderby'        => 'orderby',

			'page'           => 'paged',

			'parent'         => 'post_parent__in',

			'parent_exclude' => 'post_parent__not_in',

			'search'         => 's',

			'slug'           => 'post_name__in',

			'status'         => 'post_status',

		);

		/*

		 * For each known parameter which is both registered and present in the request,

		 * set the parameter's value on the query $args.

		 */

		foreach ( $parameter_mappings as $api_param => $wp_param ) {

			if ( isset( $registered[ $api_param ], $request[ $api_param ] ) ) {

				$args[ $wp_param ] = $request[ $api_param ];

			}

		}

		// Check for & assign any parameters which require special handling or setting.

		$args['date_query'] = array();

		// Set before into date query. Date query must be specified as an array of an array.

		if ( isset( $registered['before'], $request['before'] ) ) {

			$args['date_query'][0]['before'] = $request['before'];

		}

		// Set after into date query. Date query must be specified as an array of an array.

		if ( isset( $registered['after'], $request['after'] ) ) {

			$args['date_query'][0]['after'] = $request['after'];

		}

		// Ensure our per_page parameter overrides any provided posts_per_page filter.

		if ( isset( $registered['per_page'] ) ) {

			$args['posts_per_page'] = $request['per_page'];

		}

		if ( isset( $registered['sticky'], $request['sticky'] ) ) {

			$sticky_posts = get_option( 'sticky_posts', array() );

			if ( ! is_array( $sticky_posts ) ) {

				$sticky_posts = array();

			}

			if ( $request['sticky'] ) {

				/*

				 * As post__in will be used to only get sticky posts,

				 * we have to support the case where post__in was already

				 * specified.

				 */

				$args['post__in'] = $args['post__in'] ? array_intersect( $sticky_posts, $args['post__in'] ) : $sticky_posts;

				/*

				 * If we intersected, but there are no post ids in common,

				 * WP_Query won't return "no posts" for post__in = array()

				 * so we have to fake it a bit.

				 */

				if ( ! $args['post__in'] ) {

					$args['post__in'] = array( 0 );

				}

			} elseif ( $sticky_posts ) {

				/*

				 * As post___not_in will be used to only get posts that

				 * are not sticky, we have to support the case where post__not_in

				 * was already specified.

				 */

				$args['post__not_in'] = array_merge( $args['post__not_in'], $sticky_posts );

			}

		}

		// Force the post_type argument, since it's not a user input variable.

		$args['post_type'] = $this->post_type;

		/**

		 * Filters the query arguments for a request.

		 *

		 * Enables adding extra arguments or setting defaults for a post collection request.

		 *

		 * @since 4.7.0

		 *

		 * @link https://developer.wordpress.org/reference/classes/wp_query/

		 *

		 * @param array           $args    Key value array of query var to query value.

		 * @param WP_REST_Request $request The request used.

		 */

		$args = apply_filters( "rest_{$this->post_type}_query", $args, $request );

		$query_args = $this->prepare_items_query( $args, $request );

		$taxonomies = wp_list_filter( get_object_taxonomies( $this->post_type, 'objects' ), array( 'show_in_rest' => true ) );

		foreach ( $taxonomies as $taxonomy ) {

			$base = ! empty( $taxonomy->rest_base ) ? $taxonomy->rest_base : $taxonomy->name;

			$tax_exclude = $base . '_exclude';

			if ( ! empty( $request[ $base ] ) ) {

				$query_args['tax_query'][] = array(

					'taxonomy'         => $taxonomy->name,

					'field'            => 'term_id',

					'terms'            => $request[ $base ],

					'include_children' => false,

				);

			}

			if ( ! empty( $request[ $tax_exclude ] ) ) {

				$query_args['tax_query'][] = array(

					'taxonomy'         => $taxonomy->name,

					'field'            => 'term_id',

					'terms'            => $request[ $tax_exclude ],

					'include_children' => false,

					'operator'         => 'NOT IN',

				);

			}

		}

		$posts_query  = new WP_Query();

		$query_result = $posts_query->query( $query_args );

		// Allow access to all password protected posts if the context is edit.

		if ( 'edit' === $request['context'] ) {

			add_filter( 'post_password_required', '__return_false' );

		}

		$posts = array();

		foreach ( $query_result as $post ) {

			if ( ! $this->check_read_permission( $post ) ) {

				continue;

			}

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

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

		}

		// Reset filter.

		if ( 'edit' === $request['context'] ) {

			remove_filter( 'post_password_required', '__return_false' );

		}

		$page = (int) $query_args['paged'];

		$total_posts = $posts_query->found_posts;

		if ( $total_posts < 1 ) {

			// Out-of-bounds, run the query again without LIMIT for total count.

			unset( $query_args['paged'] );

			$count_query = new WP_Query();

			$count_query->query( $query_args );

			$total_posts = $count_query->found_posts;

		}

		$max_pages = ceil( $total_posts / (int) $posts_query->query_vars['posts_per_page'] );

		if ( $page > $max_pages && $total_posts > 0 ) {

			return new WP_Error( 'rest_post_invalid_page_number', __( 'The page number requested is larger than the number of pages available.' ), array( 'status' => 400 ) );

		}

		$response  = rest_ensure_response( $posts );

		$response->header( 'X-WP-Total', (int) $total_posts );

		$response->header( 'X-WP-TotalPages', (int) $max_pages );

		$request_params = $request->get_query_params();

		$base = add_query_arg( $request_params, rest_url( sprintf( '%s/%s', $this->namespace, $this->rest_base ) ) );

		if ( $page > 1 ) {

			$prev_page = $page - 1;

			if ( $prev_page > $max_pages ) {

				$prev_page = $max_pages;

			}

			$prev_link = add_query_arg( 'page', $prev_page, $base );

			$response->link_header( 'prev', $prev_link );

		}

		if ( $max_pages > $page ) {

			$next_page = $page + 1;

			$next_link = add_query_arg( 'page', $next_page, $base );

			$response->link_header( 'next', $next_link );

		}

		return $response;

	}

	/**

	 * Get the post, if the ID is valid.

	 *

	 * @since 4.7.2

	 *

	 * @param int $id Supplied ID.

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

	 */

	protected function get_post( $id ) {

		$error = new WP_Error( 'rest_post_invalid_id', __( 'Invalid post ID.' ), array( 'status' => 404 ) );

		if ( (int) $id <= 0 ) {

			return $error;

		}

		$post = get_post( (int) $id );

		if ( empty( $post ) || empty( $post->ID ) || $this->post_type !== $post->post_type ) {

			return $error;

		}

		return $post;

	}

	/**

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

	 *

	 * @since 4.7.0

	 *

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

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

	 */

	public function get_item_permissions_check( $request ) {

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

		if ( is_wp_error( $post ) ) {

			return $post;

		}

		if ( 'edit' === $request['context'] && $post && ! $this->check_update_permission( $post ) ) {

			return new WP_Error( 'rest_forbidden_context', __( 'Sorry, you are not allowed to edit this post.' ), array( 'status' => rest_authorization_required_code() ) );

		}

		if ( $post && ! empty( $request['password'] ) ) {

			// Check post password, and return error if invalid.

			if ( ! hash_equals( $post->post_password, $request['password'] ) ) {

				return new WP_Error( 'rest_post_incorrect_password', __( 'Incorrect post password.' ), array( 'status' => 403 ) );

			}

		}

		// Allow access to all password protected posts if the context is edit.

		if ( 'edit' === $request['context'] ) {

			add_filter( 'post_password_required', '__return_false' );

		}

		if ( $post ) {

			return $this->check_read_permission( $post );

		}

		return true;

	}