CREATE TABLE `approval_flows` (
  `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(255) NOT NULL COMMENT '流程名称',
  `type` varchar(100) NOT NULL COMMENT '业务类型标识，如 leave, reimbursement',
  `steps` json NOT NULL COMMENT '审批步骤配置',
  `is_active` tinyint(1) NOT NULL DEFAULT '1' COMMENT '是否启用',
  `timeout_hours` int(11) NOT NULL DEFAULT '0' COMMENT '实例级超时时间（小时），0为不超时',
  `timeout_action` varchar(20) NOT NULL DEFAULT 'auto_reject' COMMENT 'auto_approve | auto_reject',
  `created_at` timestamp NULL DEFAULT NULL,
  `updated_at` timestamp NULL DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `uk_flow_type` (`type`)
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8mb4 COMMENT='审批流程定义';

CREATE TABLE `approval_instances` (
  `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `flow_type` varchar(100) NOT NULL COMMENT '关联 approval_flows.type',
  `biz_id` varchar(255) NOT NULL COMMENT '业务ID',
  `biz_type` varchar(100) NOT NULL COMMENT '业务标识/表名',
  `form_data` json NOT NULL COMMENT '提交表单快照',
  `initiator_id` bigint(20) unsigned NOT NULL COMMENT '发起人',
  `status` varchar(20) NOT NULL DEFAULT 'processing' COMMENT 'processing|approved|rejected|revoked|timed_out',
  `current_step` int(11) NOT NULL DEFAULT '0' COMMENT '当前步骤索引',
  `round` int(11) NOT NULL DEFAULT '1' COMMENT '当前轮次：1=首次，重提+1',
  `finished_at` timestamp NULL DEFAULT NULL,
  `deadline_at` timestamp NULL DEFAULT NULL,
  `created_at` timestamp NULL DEFAULT NULL,
  `updated_at` timestamp NULL DEFAULT NULL,
  PRIMARY KEY (`id`),
  KEY `idx_flow_type` (`flow_type`),
  KEY `idx_biz` (`biz_type`,`biz_id`),
  KEY `idx_initiator` (`initiator_id`),
  KEY `idx_status_updated` (`status`,`updated_at`)
) ENGINE=InnoDB AUTO_INCREMENT=68 DEFAULT CHARSET=utf8mb4 COMMENT='审批实例';

CREATE TABLE `approval_records` (
  `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `instance_id` bigint(20) unsigned NOT NULL COMMENT 'approval_instances.id',
  `approver_id` bigint(20) unsigned NOT NULL COMMENT '审批人',
  `step_index` int(11) NOT NULL COMMENT '步骤索引',
  `round` int(11) NOT NULL DEFAULT '1' COMMENT '所属轮次',
  `action` varchar(20) DEFAULT NULL COMMENT 'approve|reject，待办时为NULL',
  `status` varchar(20) NOT NULL DEFAULT 'pending' COMMENT 'pending|approved|rejected|skipped|timeout',
  `comment` text COMMENT '审批意见',
  `approved_at` timestamp NULL DEFAULT NULL COMMENT '审批时间/关闭时间',
  `created_at` timestamp NULL DEFAULT NULL,
  `updated_at` timestamp NULL DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `uk_instance_step_approver` (`instance_id`,`step_index`,`approver_id`),
  KEY `idx_instance_step_status` (`instance_id`,`step_index`,`status`),
  KEY `idx_approver` (`approver_id`),
  KEY `idx_instance_step_round` (`instance_id`,`step_index`,`round`)
) ENGINE=InnoDB AUTO_INCREMENT=105 DEFAULT CHARSET=utf8mb4 COMMENT='审批记录';

CREATE TABLE `approval_transfers` (
  `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `instance_id` bigint(20) unsigned NOT NULL,
  `step_index` int(11) NOT NULL,
  `record_id` bigint(20) unsigned NOT NULL COMMENT '转交后仍然有效的记录ID（若合并则为目标记录ID）',
  `from_user_id` bigint(20) unsigned NOT NULL,
  `to_user_id` bigint(20) unsigned NOT NULL,
  `reason` text,
  `created_at` timestamp NULL DEFAULT CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`),
  KEY `idx_record` (`record_id`),
  KEY `idx_instance_step` (`instance_id`,`step_index`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='审批转交日志';

CREATE TABLE `approval_ccs` (
  `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `instance_id` bigint(20) unsigned NOT NULL,
  `user_id` bigint(20) unsigned NOT NULL,
  `notified_at` timestamp NULL DEFAULT NULL,
  `read_at` timestamp NULL DEFAULT NULL,
  `created_at` timestamp NULL DEFAULT NULL,
  `updated_at` timestamp NULL DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `uk_instance_user` (`instance_id`,`user_id`),
  KEY `idx_user` (`user_id`),
  KEY `idx_instance` (`instance_id`)
) ENGINE=InnoDB AUTO_INCREMENT=9 DEFAULT CHARSET=utf8mb4 COMMENT='审批抄送';

CREATE TABLE `approval_discussions` (
  `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `instance_id` bigint(20) unsigned NOT NULL,
  `user_id` bigint(20) unsigned NOT NULL,
  `is_internal` tinyint(1) NOT NULL DEFAULT '0' COMMENT '0=公开,1=仅审批人可见',
  `content` text NOT NULL,
  `attachments` json DEFAULT NULL,
  `created_at` timestamp NULL DEFAULT CURRENT_TIMESTAMP,
  `updated_at` timestamp NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`),
  KEY `idx_instance_id` (`instance_id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8mb4 COMMENT='审批讨论';