-- 预约充电：允许配置多个预约时段。
-- 保留 reservation_start_time / reservation_end_time 并同步第一段，便于旧版本回滚兼容。
ALTER TABLE `t_site`
    ADD COLUMN `reservation_time_ranges` JSON NULL COMMENT '允许预约时段JSON数组' AFTER `reservation_end_time`;

UPDATE `t_site`
SET `reservation_time_ranges` = JSON_ARRAY(
        JSON_OBJECT(
            'startTime', `reservation_start_time`,
            'endTime', `reservation_end_time`
        )
    )
WHERE `reservation_time_ranges` IS NULL
  AND `reservation_start_time` IS NOT NULL
  AND `reservation_start_time` <> ''
  AND `reservation_end_time` IS NOT NULL
  AND `reservation_end_time` <> '';