GoTrek - Search box input update

functions.php

// 1. Ensure search query variables are registered
add_filter( 'query_vars', function( $vars ) {
    $vars[] = 'location';
    $vars[] = 'adults';
    $vars[] = 'children';
    $vars[] = 'rooms';
    return $vars;
} );

// 2. Hook into the main WooCommerce product query
add_action( 'pre_get_posts', 'gotrek_serverside_hotel_filter', 20 );

function gotrek_serverside_hotel_filter( $query ) {
    // Only modify main queries on the frontend catalog and product search
    if ( is_admin() || ! $query->is_main_query() ) {
        return;
    }

    $post_type = $query->get( 'post_type' );
    if ( 'product' !== $post_type && ! ( is_post_type_archive( 'product' ) || is_shop() ) ) {
        return;
    }

    $location = sanitize_text_field( get_query_var( 'location', '' ) );
    $adults   = absint( get_query_var( 'adults', 0 ) );
    $children = absint( get_query_var( 'children', 0 ) );
    $rooms    = absint( get_query_var( 'rooms', 0 ) );

    // If no search parameters are present, leave standard catalog query untouched
    if ( empty( $location ) && $adults === 0 && $children === 0 && $rooms === 0 ) {
        return;
    }

    // A. Filter by Location (supports both ACF address map and text location)
    if ( ! empty( $location ) ) {
        $meta_query = (array) $query->get( 'meta_query' );
        $meta_query[] = array(
            'relation' => 'OR',
            array(
                'key'     => 'hotel_group_location_map',
                'value'   => $location,
                'compare' => 'LIKE',
            ),
            array(
                'key'     => 'hotel_group_location',
                'value'   => $location,
                'compare' => 'LIKE',
            ),
        );
        $query->set( 'meta_query', $meta_query );
    }

    // B. Filter by Guest & Room Capacity
    if ( $adults > 0 || $children > 0 || $rooms > 0 ) {
        $matching_ids = gotrek_get_matching_capacity_hotel_ids( $adults, $children, $rooms );

        if ( ! empty( $matching_ids ) ) {
            $existing_post_in = $query->get( 'post__in' );
            if ( ! empty( $existing_post_in ) ) {
                $matching_ids = array_intersect( $existing_post_in, $matching_ids );
            }
            $query->set( 'post__in', ! empty( $matching_ids ) ? $matching_ids : array( 0 ) );
        } else {
            // No hotels meet capacity -> return empty set cleanly
            $query->set( 'post__in', array( 0 ) );
        }
    }
}

/**
 * Helper: Query hotel products matching capacity requirements.
 * Cached in transients to prevent database overhead.
 */
function gotrek_get_matching_capacity_hotel_ids( $req_adults, $req_children, $req_rooms ) {
    $cache_key  = sprintf( 'gotrek_cap_a%d_c%d_r%d', $req_adults, $req_children, $req_rooms );
    $cached_ids = get_transient( $cache_key );

    if ( false !== $cached_ids ) {
        return $cached_ids;
    }

    $all_hotels = get_posts( array(
        'post_type'      => 'product',
        'posts_per_page' => -1,
        'post_status'    => 'publish',
        'fields'         => 'ids',
        'meta_query'     => array(
            'relation' => 'OR',
            array(
                'key'     => 'hotel_group_rooms',
                'compare' => 'EXISTS',
            ),
            array(
                'key'     => 'room_group_max_adult',
                'compare' => 'EXISTS',
            ),
        ),
    ) );

    $matching_ids = array();

    foreach ( $all_hotels as $product_id ) {
        $hotel_rooms = get_post_meta( $product_id, 'hotel_group_rooms', true );

        // Scenario 1: Parent Hotel with associated Rooms
        if ( ! empty( $hotel_rooms ) && is_array( $hotel_rooms ) ) {
            $rooms_count    = count( $hotel_rooms );
            $max_adults     = 0;
            $max_children   = 0;
            $total_adults   = 0;
            $total_children = 0;

            foreach ( $hotel_rooms as $room ) {
                $room_id = is_object( $room ) ? $room->ID : absint( $room );

                $r_adults = 0;
                $r_child  = 0;

                if ( function_exists( 'get_field' ) ) {
                    $rg = get_field( 'room_group', $room_id, false );
                    if ( is_array( $rg ) ) {
                        $r_adults = isset( $rg['max_adult'] ) ? absint( $rg['max_adult'] ) : 0;
                        $r_child  = isset( $rg['max_children'] ) ? absint( $rg['max_children'] ) : 0;
                    }
                }
                if ( ! $r_adults ) {
                    $r_adults = absint( get_post_meta( $room_id, 'room_group_max_adult', true ) );
                }
                if ( ! $r_child ) {
                    $r_child  = absint( get_post_meta( $room_id, 'room_group_max_children', true ) );
                }

                $total_adults   += $r_adults;
                $total_children += $r_child;

                if ( $r_adults > $max_adults )     $max_adults = $r_adults;
                if ( $r_child > $max_children )   $max_children = $r_child;
            }

            // Exceeds available rooms count
            if ( $req_rooms > 0 && $rooms_count < $req_rooms ) {
                continue;
            }

            // Single room request: check single room capacity
            if ( $req_rooms === 1 ) {
                if ( $req_adults > 0 && $req_adults > $max_adults )     continue;
                if ( $req_children > 0 && $req_children > $max_children ) continue;
            } else {
                // Multi-room request: check total capacity
                if ( $req_adults > 0 && $req_adults > $total_adults )     continue;
                if ( $req_children > 0 && $req_children > $total_children ) continue;
            }

            $matching_ids[] = $product_id;

        } else {
            // Scenario 2: Direct standalone Room product
            $r_adults = absint( get_post_meta( $product_id, 'room_group_max_adult', true ) );
            $r_child  = absint( get_post_meta( $product_id, 'room_group_max_children', true ) );

            if ( $req_rooms > 1 ) continue;
            if ( $req_adults > 0 && $req_adults > $r_adults ) continue;
            if ( $req_children > 0 && $req_children > $r_child ) continue;

            $matching_ids[] = $product_id;
        }
    }

    set_transient( $cache_key, $matching_ids, HOUR_IN_SECONDS );
    return $matching_ids;
}

// Invalidate cache when any hotel/room product is updated
add_action( 'save_post_product', function() {
    global $wpdb;
    $wpdb->query( "DELETE FROM {$wpdb->options} WHERE option_name LIKE '_transient_gotrek_cap_%' OR option_name LIKE '_transient_timeout_gotrek_cap_%'" );
} );