Customize Related Posts

function jetpackme_more_related_posts( $options ) {
    $options['size'] = 6;
    return $options;
}
add_filter( 'jetpack_relatedposts_filter_options', 'jetpackme_more_related_posts' );

/**
 * Display the post author after the Related Posts context.
 *
 * @param string $context Context displayed below each related post.
 * @param string $post_id Post ID of the post for which we are retrieving Related Posts.
 *
 * @return string $context Context, including information about the post author.
 */
function jetpackme_related_authors( $context, $post_id ) {
	// Get the author ID.
	$post_author = get_post_field( 'post_author', $post_id );

	// Get the author's display name.
	$author_display_name = get_the_author_meta( 'display_name', $post_author );

	// Add the author name after the existing context.
	if ( isset( $author_display_name ) && ! empty( $author_display_name ) ) {
		return sprintf(
			__( '%1$s<span class="jp-relatedposts-post-author">By %2$s</span>', 'my-plugin-slug' ),
			$context,
			esc_html( $author_display_name )
		);
	}

	// Final fallback.
	return $context;
}
add_filter( 'jetpack_relatedposts_filter_post_context', 'jetpackme_related_authors', 10, 2 );

function jetpackme_remove_rp() {
	if ( class_exists( 'Jetpack_RelatedPosts' ) ) {
		$jprp = Jetpack_RelatedPosts::init();
		$callback = array( $jprp, 'filter_add_target_to_dom' );

		remove_filter( 'the_content', $callback, 40 );
	}
}
add_action( 'wp', 'jetpackme_remove_rp', 20 );

if ( class_exists( 'Jetpack_RelatedPosts' ) ) {
	echo do_shortcode( '[jetpack-related-posts]' );
}

function jetpackme_related_posts_headline( $headline ) {
	$headline = sprintf(
		'<p>
			<h3><em>%s</em></h3>
		</p>',
		esc_html( 'Check These Out!' )
	);

	return $headline;
}
add_filter( 'jetpack_relatedposts_filter_headline', 'jetpackme_related_posts_headline' );

function jetpackme_append_related_post( $hits, $post_id ) {
	// $post_id is the post we are currently getting related posts for.
	if ( 2194 === $post_id ) {
		// Add 1036 to the front of the hits array.
		array_unshift( $hits, array( 'id' => 1036 ) );

		// Remove the last element of the array.
		array_pop( $hits );
	}
	return $hits;
}
add_filter( 'jetpack_relatedposts_filter_hits', 'jetpackme_append_related_post', 20, 2 );

function jetpackme_exclude_related_post( $exclude_post_ids, $post_id ) {
	// $post_id is the post we are currently getting related posts for

	$exclude_post_ids[] = 1037; // Exclude post_id 1037.
	$exclude_post_ids[] = 1038;// Also exclude post_id 1038.

	return $exclude_post_ids;
}
add_filter( 'jetpack_relatedposts_filter_exclude_post_ids', 'jetpackme_exclude_related_post', 20, 2 );

function jetpackme_exclude_sticky( $exclude_post_ids, $post_id ) {
	$sticky = get_option( 'sticky_posts' );

	if ( ! is_array( $exclude_post_ids ) ) {
		$exclude_post_ids = array();
	}

	if ( is_array( $sticky ) ) {
		$exclude_post_ids = array_merge( $sticky, $exclude_post_ids );
	}

	return $exclude_post_ids;
}
add_filter( 'jetpack_relatedposts_filter_exclude_post_ids', 'jetpackme_exclude_sticky', 20, 2 );

function jetpackme_filter_exclude_category( $filters ) {
	$filters[] = array(
		'not' => array(
			'term' => array(
				'category.slug' => 'dogs',
			),
		),
	);

	return $filters;
}
add_filter( 'jetpack_relatedposts_filter_filters', 'jetpackme_filter_exclude_category' );

function jetpackme_filter_exclude_uncategorized( $filters ) {
	$filters[] = array(
		'exists' => array(
			'field' => 'category.slug',
		),
	);

	$filters[] = array(
		'not' => array(
			'term' => 'uncategorized',
		),
	);

	return $filters;
}
add_filter( 'jetpack_relatedposts_filter_filters', 'jetpackme_filter_exclude_uncategorized' );

function jetpackme_no_related_posts( $options ) {
	if (
		is_single(
			array( 17, 19, 1, 11 )
		)
	) {
		$options['enabled'] = false;
	}

	return $options;
}
add_filter( 'jetpack_relatedposts_filter_options', 'jetpackme_no_related_posts' );

function jetpackme_allow_pages_for_relatedposts( $enabled ) {
	if ( is_page() ) {
		$enabled = true;
	}

	return $enabled;
}
add_filter( 'jetpack_relatedposts_filter_enabled_for_request', 'jetpackme_allow_pages_for_relatedposts' );

function jetpackme_add_pages_to_related( $post_type, $post_id ) {
	if ( is_array( $post_type ) ) {
		$search_types = $post_type;
	} else {
		$search_types = array( $post_type );
	}

	// Add pages.
	$search_types[] = 'page';

	return $search_types;
}
add_filter( 'jetpack_relatedposts_filter_post_type', 'jetpackme_add_pages_to_related', 10, 2 );

function jetpackme_no_related_posts_onpages( $options ) {
    if ( is_page( 11 ) ) {
        $options['enabled'] = false;
    }
    return $options;
}
add_filter( 'jetpack_relatedposts_filter_options', 'jetpackme_no_related_posts_onpages' );

function jetpackme_allow_my_post_types( $allowed_post_types ) {
	$allowed_post_types[] = 'your-post-type';

	return $allowed_post_types;
}
add_filter( 'rest_api_allowed_post_types', 'jetpackme_allow_my_post_types' );

/**
 * Create a [jprel] shortcode.
 *
 * @param array $atts Shortcode attributes.
 */
function jetpackme_custom_related( $atts ) {
	$posts_titles = array();

	if (
		class_exists( 'Jetpack_RelatedPosts' )
		&& method_exists( 'Jetpack_RelatedPosts', 'init_raw' )
	) {
		$related = Jetpack_RelatedPosts::init_raw()
			->set_query_name( 'jetpackme-shortcode' ) // Optional, name can be anything.
			->get_for_post_id(
				get_the_ID(),
				array( 'size' => 3 )
			);

		if ( $related ) {
			foreach ( $related as $result ) {
				// Get the related post IDs.
				$related_post = get_post( $result['id'] );

				// From there you can do just about anything. Here we get the post titles.
				$posts_titles[] = $related_post->post_title;
			}
		}
	}

	// Return a list of post titles separated by commas.
	return implode( ', ', $posts_titles );
}
add_shortcode( 'jprel', 'jetpackme_custom_related' );

function jetpackme_exclude_jetpack_related_from_products( $options ) {
	if ( is_product() ) {
		$options['enabled'] = false;
	}

	return $options;
}
add_filter( 'jetpack_relatedposts_filter_options', 'jetpackme_exclude_jetpack_related_from_products' );

function jetpackme_related_posts_past_halfyear_only( $date_range ) {
	$date_range = array(
		'from' => strtotime( '-6 months' ),
		'to'   => time(),
	);

	return $date_range;
}
add_filter( 'jetpack_relatedposts_filter_date_range', 'jetpackme_related_posts_past_halfyear_only' );