<?php
/**
 * Keeps the plugin's own pages out of menus, search results and sitemaps.
 *
 * The Payment Pending, Payment Receipt and Payment Request pages only make sense when a customer
 * arrives with a private link, so they should never appear in a site's navigation, be listed by a
 * search engine, or show up in a sitemap.
 *
 * @package AfriDirect_Payment
 */

// Exit if accessed directly.
if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Page visibility class.
 */
class AfriDirect_Payment_Page_Visibility {

	/**
	 * Plugin instance.
	 *
	 * @var AfriDirect_Payment_Page_Visibility
	 */
	private static $instance = null;

	/**
	 * Get plugin instance.
	 *
	 * @return AfriDirect_Payment_Page_Visibility
	 */
	public static function instance() {
		if ( is_null( self::$instance ) ) {
			self::$instance = new self();
		}
		return self::$instance;
	}

	/**
	 * Constructor.
	 */
	private function __construct() {
		// Page lists: wp_list_pages(), the fallback menu and the Page List block.
		add_filter( 'get_pages', array( $this, 'exclude_from_page_lists' ) );
		// Menus built under Appearance > Menus, including ones that add new pages automatically.
		add_filter( 'wp_get_nav_menu_items', array( $this, 'exclude_from_menus' ) );
		// Links inside a block theme's Navigation block.
		add_filter( 'render_block_core/navigation-link', array( $this, 'exclude_navigation_link' ), 10, 2 );
		// Search engines.
		add_filter( 'wp_robots', array( $this, 'noindex' ) );
		add_filter( 'wp_sitemaps_posts_query_args', array( $this, 'exclude_from_sitemap' ), 10, 2 );
	}

	/**
	 * IDs of the pages the plugin creates for itself.
	 *
	 * @return int[]
	 */
	public static function page_ids() {
		return array_values(
			array_filter(
				array(
					(int) get_option( 'afridirect_pending_page_id', 0 ),
					(int) get_option( 'afridirect_receipt_page_id', 0 ),
					(int) get_option( 'afridirect_request_page_id', 0 ),
				)
			)
		);
	}

	/**
	 * Remove the plugin's pages from automatic page lists on the public site.
	 *
	 * @param WP_Post[] $pages Pages.
	 * @return WP_Post[]
	 */
	public function exclude_from_page_lists( $pages ) {
		if ( is_admin() || ! is_array( $pages ) ) {
			return $pages;
		}

		$hidden = self::page_ids();
		if ( empty( $hidden ) ) {
			return $pages;
		}

		return array_values(
			array_filter(
				$pages,
				static function ( $page ) use ( $hidden ) {
					return ! ( $page instanceof WP_Post ) || ! in_array( (int) $page->ID, $hidden, true );
				}
			)
		);
	}

	/**
	 * Remove the plugin's pages from menus on the public site.
	 *
	 * @param array $items Menu items.
	 * @return array
	 */
	public function exclude_from_menus( $items ) {
		if ( is_admin() || ! is_array( $items ) ) {
			return $items;
		}

		$hidden = self::page_ids();
		if ( empty( $hidden ) ) {
			return $items;
		}

		return array_values(
			array_filter(
				$items,
				static function ( $item ) use ( $hidden ) {
					return ! ( isset( $item->object, $item->object_id ) && 'page' === $item->object && in_array( (int) $item->object_id, $hidden, true ) );
				}
			)
		);
	}

	/**
	 * Hide a Navigation block link that points at one of the plugin's pages.
	 *
	 * @param string $content Rendered block.
	 * @param array  $block   Parsed block.
	 * @return string
	 */
	public function exclude_navigation_link( $content, $block ) {
		$attrs = isset( $block['attrs'] ) ? $block['attrs'] : array();

		if ( isset( $attrs['id'], $attrs['type'] ) && 'page' === $attrs['type'] && in_array( (int) $attrs['id'], self::page_ids(), true ) ) {
			return '';
		}

		return $content;
	}

	/**
	 * Ask search engines not to list the plugin's pages.
	 *
	 * @param array $robots Robots directives.
	 * @return array
	 */
	public function noindex( $robots ) {
		$hidden = self::page_ids();

		if ( ! empty( $hidden ) && is_page( $hidden ) ) {
			return wp_robots_no_robots( $robots );
		}

		return $robots;
	}

	/**
	 * Keep the plugin's pages out of the WordPress sitemap.
	 *
	 * @param array  $args      Query arguments.
	 * @param string $post_type Post type.
	 * @return array
	 */
	public function exclude_from_sitemap( $args, $post_type ) {
		if ( 'page' === $post_type ) {
			$existing = isset( $args['post__not_in'] ) ? (array) $args['post__not_in'] : array();
			// Only the plugin's three pages are excluded, so this exclusion costs nothing.
			// phpcs:ignore WordPressVIPMinimum.Performance.WPQueryParams.PostNotIn_post__not_in
			$args['post__not_in'] = array_merge( $existing, self::page_ids() );
		}

		return $args;
	}
}