<?php

/**
 * Multisite upgrade administration panel.
 *
 * @package WordPress
 * @subpackage Multisite
 * @since 3.0.0
 */


/** Load WordPress Administration Bootstrap */
require_once __DIR__ . '/admin.php';

require_once ABSPATH . WPINC . '/http.php';

// Used in the HTML title tag.
$title       = __( 'Upgrade Network' );
$parent_file = 'upgrade.php';

get_current_screen()->add_help_tab(
  array(
    'id'      => 'overview',
    'title'   => __( 'Overview' ),
    'content' =>
      '<p>' . __( 'Only use this screen once you have updated to a new version of WordPress through Updates/Available Updates (via the Network Administration navigation menu or the Toolbar). Clicking the Upgrade Network button will step through each site in the network, five at a time, and make sure any database updates are applied.' ) . '</p>' .
      '<p>' . __( 'If a version update to core has not happened, clicking this button will not affect anything.' ) . '</p>' .
      '<p>' . __( 'If this process fails for any reason, users logging in to their sites will force the same update.' ) . '</p>',
  )
);

get_current_screen()->set_help_sidebar(
  '<p><strong>' . __( 'For more information:' ) . '</strong></p>' .
  '<p>' . __( '<a href="https://wordpress.org/documentation/article/network-admin-updates-screen/">Documentation on Upgrade Network</a>' ) . '</p>' .
  '<p>' . __( '<a href="https://wordpress.org/support/forums/">Support forums</a>' ) . '</p>'
);

require_once ABSPATH . 'wp-admin/admin-header.php';

if ( ! current_user_can( 'upgrade_network' ) ) {
  wp_die( __( 'Sorry, you are not allowed to access this page.' ), 403 );
}

echo '<div class="wrap">';
echo '<h1>' . __( 'Upgrade Network' ) . '</h1>';

$action = isset( $_GET['action'] ) ? $_GET['action'] : 'show';

switch ( $action ) {
  case 'upgrade':
    $n = ( isset( $_GET['n'] ) ) ? (int) $_GET['n'] : 0;

    if ( $n < 5 ) {
      
/**
 * @global int $wp_db_version WordPress database version.
 */
      global $wp_db_version;
      update_site_option( 'wpmu_upgrade_site', $wp_db_version );
    }

    $site_ids = get_sites(
      array(
        'spam'                   => 0,
        'deleted'                => 0,
        'archived'               => 0,
        'network_id'             => get_current_network_id(),
        'number'                 => 5,
        'offset'                 => $n,
        'fields'                 => 'ids',
        'order'                  => 'DESC',
        'orderby'                => 'id',
        'update_site_meta_cache' => false,
      )
    );
    if ( empty( $site_ids ) ) {
      echo '<p>' . __( 'All done!' ) . '</p>';
      break;
    }
    echo '<ul>';
    foreach ( (array) $site_ids as $site_id ) {
      switch_to_blog( $site_id );
      $siteurl     = site_url();
      $upgrade_url = admin_url( 'upgrade.php?step=upgrade_db' );
      restore_current_blog();

      echo "<li>$siteurl</li>";

      $response = wp_remote_get(
        $upgrade_url,
        array(
          'timeout'     => 120,
          'httpversion' => '1.1',
          'sslverify'   => false,
        )
      );

      if ( is_wp_error( $response ) ) {
        wp_die(
          sprintf(
            /* translators: 1: Site URL, 2: Server error message. */
            __( 'Warning! Problem updating %1$s. Your server may not be able to connect to sites running on it. Error message: %2$s' ),
            $siteurl,
            '<em>' . $response->get_error_message() . '</em>'
          )
        );
      }

      
/**
 * Fires after the Multisite DB upgrade for each site is complete.
 *
 * @since MU (3.0.0)
 *
 * @param array $response The upgrade response array.
 */
      do_action( 'after_mu_upgrade', $response );

      
/**
 * Fires after each site has been upgraded.
 *
 * @since MU (3.0.0)
 *
 * @param int $site_id The Site ID.
 */
      do_action( 'wpmu_upgrade_site', $site_id );
    }
    echo '</ul>';
    ?><p><?php _e( 'If your browser does not start loading the next page automatically, click this link:' ); ?> <a class="button" href="upgrade.php?action=upgrade&n=<?php echo ( $n + 5 ); ?>"><?php _e( 'Next Sites' ); ?></a></p>
		<script type="text/javascript">
		<!--
		function nextpage() {
			location.href = "upgrade.php?action=upgrade&n=<?php echo ( $n + 5 ); ?>";
		}
		setTimeout( "nextpage()", 250 );
		//-->
		</script>
		<?php
    break;
  case 'show':
  default:
    if ( (int) get_site_option( 'wpmu_upgrade_site' ) !== $GLOBALS['wp_db_version'] ) :
      ?>
		<h2><?php _e( 'Database Update Required' ); ?></h2>
		<p><?php _e( 'WordPress has been updated! Next and final step is to individually upgrade the sites in your network.' ); ?></p>
		<?php endif; ?>

		<p><?php _e( 'The database update process may take a little while, so please be patient.' ); ?></p>
		<p><a class="button button-primary" href="upgrade.php?action=upgrade"><?php _e( 'Upgrade Network' ); ?></a></p>
		<?php
    
/**
 * Fires before the footer on the network upgrade screen.
 *
 * @since MU (3.0.0)
 */
    do_action( 'wpmu_upgrade_page' );
    break;
}
?>
</div>

<?php require_once ABSPATH . 'wp-admin/admin-footer.php'; ?>