<?php
/**
* Sitemaps: Public functions
*
* This file contains a variety of public functions developers can use to interact with
* the XML Sitemaps API.
*
* @package WordPress
* @subpackage Sitemaps
* @since 5.5.0
*/

/**
* Retrieves the current Sitemaps server instance.
*
* @since 5.5.0
*
* @global WP_Sitemaps $wp_sitemaps Global Core Sitemaps instance.
*
* @return WP_Sitemaps Sitemaps instance.
*/
function wp_sitemaps_get_server() {
global $wp_sitemaps;

// If there isn't a global instance, set and bootstrap the sitemaps system.
if ( empty( $wp_sitemaps ) ) {
$wp_sitemaps = new WP_Sitemaps();
$wp_sitemaps->init();

/**
* Fires when initializing the Sitemaps object.
*
* Additional sitemaps should be registered on this hook.
*
* @since 5.5.0
*
* @param WP_Sitemaps $wp_sitemaps Sitemaps object.
*/
do_action( 'wp_sitemaps_init', $wp_sitemaps );
}

return $wp_sitemaps;
}

/**
* Gets an array of sitemap providers.
*
* @since 5.5.0
*
* @return WP_Sitemaps_Provider[] Array of sitemap providers.
*/
function wp_get_sitemap_providers() {
$sitemaps = wp_sitemaps_get_server();

return $sitemaps->registry->get_providers();
}

/**
* Registers a new sitemap provider.
*
* @since 5.5.0
*
* @param string $name Unique name for the sitemap provider.
* @param WP_Sitemaps_Provider $provider The `Sitemaps_Provider` instance implementing the sitemap.
* @return bool Whether the sitemap was added.
*/
function wp_register_sitemap_provider( $name, WP_Sitemaps_Provider $provider ) {
$sitemaps = wp_sitemaps_get_server();

return $sitemaps->registry->add_provider( $name, $provider );
}

/**
* Gets the maximum number of URLs for a sitemap.
*
* @since 5.5.0
*
* @param string $object_type Object type for sitemap to be filtered (e.g. 'post', 'term', 'user').
* @return int The maximum number of URLs.
*/
function wp_sitemaps_get_max_urls( $object_type ) {
/**
* Filters the maximum number of URLs displayed on a sitemap.
*
* @since 5.5.0
*
* @param int $max_urls The maximum number of URLs included in a sitemap. Default 2000.
* @param string $object_type Object type for sitemap to be filtered (e.g. 'post', 'term', 'user').
*/
return apply_filters( 'wp_sitemaps_max_urls', 2000, $object_type );
}

/**
* Retrieves the full URL for a sitemap.
*
* @since 5.5.1
*
* @param string $name The sitemap name.
* @param string $subtype_name The sitemap subtype name. Default empty string.
* @param int $page The page of the sitemap. Default 1.
* @return string|false The sitemap URL or false if the sitemap doesn't exist.
*/
function get_sitemap_url( $name, $subtype_name = '', $page = 1 ) {
$sitemaps = wp_sitemaps_get_server();

if ( ! $sitemaps ) {
return false;
}

if ( 'index' === $name ) {
return $sitemaps->index->get_index_url();
}

$provider = $sitemaps->registry->get_provider( $name );
if ( ! $provider ) {
return false;
}

if ( $subtype_name && ! in_array( $subtype_name, array_keys( $provider->get_object_subtypes() ), true ) ) {
return false;
}

$page = absint( $page );
if ( 0 >= $page ) {
$page = 1;
}

return $provider->get_sitemap_url( $subtype_name, $page );
}