<?php

namespace PluginNamespace\Front;

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

class Rewrites {

	/**
	 * Class constructor.
	 *
	 * @package PluginNamespace\Front\Rewrites
	 * @since 1.0.0
	 *
	 * @return void
	 */
	public function __construct() {
		add_action( 'init', array( $this, 'add_rewrite_rules' ), 5 );

		add_filter( 'query_vars', array( $this, 'custom_query_vars' ) );
		add_filter( 'nmsp_plugin_name_rewrite_urls', array( $this, 'build_rewrite_urls' ) );
	}

	/**
	 * Generate new rewrite rules and flush the cached values.
	 *
	 * @package PluginNamespace\Front\Rewrites
	 * @since 1.0.0
	 *
	 * @return void
	 */
	public function add_rewrite_rules(): void {
		$filters = apply_filters( 'nmsp_plugin_name_rewrite_urls', array() );

		add_rewrite_tag( 'foo', '([0-9]+)' );

		if ( is_iterable( $filters ) && count( $filters ) > 0 ) {
			foreach ( $filters as $item ) {
				if ( $item['slug'] ) {
					$slug = str_replace( home_url() . '/', '', get_permalink( $item['id'] ) );
					add_rewrite_rule( '^' . $slug . '([^/]*' . $item['var'] . ')/([^/]*)/?', 'index.php?page_id=' . $item['id'] . '&$matches[1]=$matches[2]', 'top' );
				}
			}

			flush_rewrite_rules();
		}
	}

	/**
	 * Build the array of post IDs that have a slug for the URL
	 * along with what custom query variable to use.
	 *
	 * @package PluginNamespace\Front\Rewrites
	 * @since 1.0.0
	 *
	 * @return array<int, array<string, string>>
	 */
	public function build_rewrite_urls(): array {
		$pages = array();

		$page_list = array(
			'NMSP_PLUGIN_SLUG_PAGE_NAME' => array( 'foo' ),
		);

		foreach ( $page_list as $key => $params ) {
			$page_id = get_option( constant( $key ) );
			$page = ( $page_id ) ? get_post( $page_id ) : false;
			if ( ! empty( $page ) ) {
				foreach ( $params as $param ) {
					$pages[] = array(
						'id'   => $page_id,
						'slug' => $page->post_name,
						'var'  => $param,
					);
				}
			}
		}

		return $pages;
	}

	/**
	 * Append custom query variables to the list WordPress maintinas
	 * with each request.
	 *
	 * @package PluginNamespace\Front\Rewrites
	 * @since 1.0.0
	 *
	 * @param array<int, string> $vars
	 *
	 * @return array<int, string>
	 */
	public function custom_query_vars( array $vars ): array {
		$vars[] = 'foo';
		return $vars;
	}
}

new Rewrites();