WordPress Post Navigation for Private Posts

single.php

<nav class="navigation post-navigation" role="navigation" aria-label="Posts">
  <h2 class="screen-reader-text">Post Navigation</h2>
  <div class="nav-links">
  <?php
  global $wpdb;
  $results = $wpdb->get_results(
    $wpdb->prepare(
      "
      SELECT *
      FROM $wpdb->posts
      WHERE ID < (
        SELECT ID
        FROM $wpdb->posts
        WHERE ID = %d
        AND post_type = %s
        AND post_status = %s
        ORDER BY ID DESC
      )
      AND post_type = %s
      AND post_status = %s
      ORDER BY ID DESC
      LIMIT 1
      ",
      get_the_ID(),
      'rotonews', // The post type.
      'private', // The post status.
      'rotonews',
      'private'
    )
  );

  // var_dump( $results );

  /**
   * Check to see if a previous post was found
   *
   * @param array $results the results of the query to determined if there are past posts.
   *
   * @return bool true if there is a previous post; otherwise, false
   */
  function has_previous_post( $results ) {
    return isset( $results[0] );
  }

  // If a previous post is found show the link.
  if ( has_previous_post( $results ) == 1 ) {
    ?>
    <div class="nav-previous">
      <a href="<?php echo esc_url( get_the_permalink( $results[0]->ID ) ); ?>" rel="prev">
        <span class="meta-nav" aria-hidden="true">Previous</span>
        <span class="screen-reader-text">Previous post:</span>
        <span class="post-title"><?php echo esc_attr( get_the_title( $results[0]->ID ) ); ?></span>
      </a>
    </div>
    <?php
  }

  global $wpdb;
  $results = $wpdb->get_results(
    $wpdb->prepare(
      "
      SELECT *
      FROM $wpdb->posts
      WHERE ID > (
        SELECT ID
        FROM $wpdb->posts
        WHERE ID = %d
        AND post_type = %s
        AND post_status = %s
        ORDER BY ID ASC
      )
      AND post_type = %s
      AND post_status = %s
      ORDER BY ID ASC
      LIMIT 1
      ",
      get_the_ID(),
      'rotonews', // The post type.
      'private', // The post status.
      'rotonews',
      'private'
    )
  );

  // var_dump( $results );

  /**
   * Check to see if a next post was found_posts
   *
   * @param array $results the results of the query to determined if there are future posts.
   *
   * @return bool true if there is a next post; otherwise, false
   */
  function has_next_post( $results ) {
    return isset( $results[0] );
  }
    
  // If a next post is found show the link.
  if ( has_next_post( $results ) == 1 ) {
  ?>
    <div class="nav-next">
      <a href="<?php echo esc_url( get_the_permalink( $results[0]->ID ) ); ?>" rel="next">
        <span class="meta-nav" aria-hidden="true">Next</span>
        <span class="screen-reader-text">Next post:</span>
        <span class="post-title"><?php echo esc_attr( get_the_title( $results[0]->ID ) ); ?></span>
      </a>
    </div>
  <?php
  }
  ?>
  </div><!-- .nav-links -->
</nav><!-- .post-navigation -->