Relevanssi category sorting

rlv_category_sort.php

<?php

// Add this to theme functions.php

add_filter( 'relevanssi_hits_filter', 'rlv_category_sort' );
function rlv_category_sort( $hits ) {
	$gold   = array();
	$silver = array();
	$bronze = array();
	$everything_else = array();
	foreach ( $hits[0] as $hit ) {
		$sorted = false;
		foreach ( get_the_category( $hit->ID ) as $cat ) {
			if ( 'gold' === strtolower( $cat->name ) ) {
				array_push( $gold, $hit );
				$sorted = true;
				break;
			}
			if ( 'silver' === strtolower( $cat->name ) ) {
				array_push( $silver, $hit );
				$sorted = true;
				break;
			}
			if ( 'bronze' === strtolower( $cat->name ) ) {
				array_push( $bronze, $hit );
				$sorted = true;
				break;
			}
		}
		if ( ! $sorted ) {
			array_push( $everything_else, $hit );
		}
	}
 
	$hits[0] = array_merge( $gold, $silver, $bronze, $everything_else );
	return $hits;
}