FacetWP - create a dropdown to filter by "min_beds" (minimum range)

functions.php

<?php

/*
 * Facet name: beds
 * Facet type: dropdown
 * Data source: "min_beds"
 *
 * This hook will index all values between min_beds and max_beds. If min_beds = 2 and max_beds = 5,
 * then the values "2", "3", "4" and "5" will get indexed for this post.
 */
add_filter( 'facetwp_indexer_row_data', function( $rows, $params ) {
    if ( 'beds' == $params['facet']['name'] ) {
        $post_id = (int) $params['defaults']['post_id'];
        $min_beds = (int) get_field( 'min_beds', $post_id );
        $max_beds = (int) get_field( 'max_beds', $post_id );

        $rows = [];
        for ( $i = $min_beds; $i <= $max_beds; $i++ ) {
            $new_row = $params['defaults'];
            $new_row['facet_value'] = $i;
            $new_row['facet_display_value'] = $i;
            $rows[] = $new_row;
        }
    }
    return $rows;
}, 10, 2 );