Woocommerce Advanced Shipping - Total Bottles

/**  Woocommerce Advanced Shipping (WAS)  **/

function custom_get_total_bottles_in_cart() {

    $total_bottles = 0;

    // Only run in the Cart or Checkout pages
    if ( is_cart() || is_checkout() ) {

        //loop through all cart products
        foreach ( WC()->cart->cart_contents as $product ) {

            // See https://docs.woothemes.com/wc-apidocs/source-class-WC_Product.html#1333
            $total_bottles += $product->get_attribute( 'bottles' );
        }
    }
    return $total_bottles;
}


/**
 * Add condition to conditions list.
 *
 * @param   array   $conditions List of existing conditions.
 * @return  aray            List of modified conditions.
 */
function was_conditions_add_bottles( $conditions ) {

    // 'General', 'User Details', 'Cart' are default groups, you can also use something custom
    $conditions['General']['bottlenum'] = __( 'Bottles', 'woocommerce-advanced-shipping' );
    return $conditions;
}
add_filter( 'was_conditions', 'was_conditions_add_bottles', 10, 1 );


/**
 * Add value field for 'bottles' condition
 *
 * @param   array   $values     List of value field arguments
 * @param   string  $condition  Name of the condition.
 * @return  array   $values     List of modified value field arguments.
 */
function was_values_add_bottles( $values, $condition ) {
    switch ( $condition ) {
        case 'bottlenum':
            $values['field'] = 'text';
            $values['placeholder']  = 'ie. 3';
        break;
    }
    return $values;
}
add_filter( 'was_values', 'was_values_add_bottles', 10, 2 );


/**
 * Must match quantity of bottles.
 *
 * @param  bool   $match    Current matching status. Default false.
 * @param  string $operator Store owner selected operator.
 * @param  mixed  $value    Store owner given value.
 * @param  array  $package  Shipping package.
 * @return bool             If the current user/environment matches this condition.
 */
function was_match_condition_bottles( $match, $operator, $value, $package ) {

    // Set total quantity of bottles in cart

    $total_bottles = custom_get_total_bottles_in_cart();

    // Check if value exists
    if ( $value ) :
        if ( $operator == '==' ) :
            $match = ( $total_bottles == $value );
        elseif ( $operator == '!=' ) :
            $match = ( $total_bottles != $value );
        elseif ( $operator == '>=' ) :
            $match = ( $total_bottles >= $value );
        elseif ( $operator == '<=' ) :
            $match = ( $total_bottles <= $value );
        endif;
    endif;
    return $match;
}
add_action( 'was_match_condition_bottlenum', 'was_match_condition_bottles', 10, 4 );