-- ============================================================
-- 存量数据回填脚本
-- 1. notice.sch_id：按发布人所属学校回填（从 sys_user_role_rel 取 main=1 的 sch_id）
-- 2. notice_receiver：从 notice.receive_list JSON 字符串展开为关联表行
--
-- 幂等设计：可重复执行，已存在的数据不会重复插入
-- 执行方式：由 DBA 手动在对应环境执行，AI 不代跑
-- MySQL 5.7+ 兼容
-- ============================================================

-- ============================================================
-- Part 1：回填 notice.sch_id
-- ============================================================

-- 方式一：如果 base_user / sys_user 表有 sch_id 字段，直接关联回填
-- 注意：需根据实际平台库表结构调整关联条件
UPDATE `notice` n
    INNER JOIN (
        SELECT DISTINCT u.login_name, u.sch_id
        FROM base_user u
        WHERE u.sch_id IS NOT NULL
    ) t ON n.publisher_account = t.login_name
SET n.sch_id = t.sch_id
WHERE n.sch_id IS NULL
  AND n.publisher_account IS NOT NULL
  AND n.publisher_account != '';

-- 方式二（备用）：如果用户学校关系在 sys_user_role_rel 表
-- 取每个用户的主身份学校（is_main=1），回填 sch_id
-- 取消注释后执行（视实际库表结构选用）
--
-- UPDATE `notice` n
--     INNER JOIN (
--         SELECT r.account, r.sch_id
--         FROM sys_user_role_rel r
--         WHERE r.is_main = 1
--           AND r.sch_id IS NOT NULL
--     ) t ON n.publisher_account = t.account
-- SET n.sch_id = t.sch_id
-- WHERE n.sch_id IS NULL
--   AND n.publisher_account IS NOT NULL
--   AND n.publisher_account != '';


-- ============================================================
-- Part 2：从 notice.receive_list 展开到 notice_receiver 关联表
-- ============================================================

-- 说明：
-- - notice.receive_list 存储格式有两种：
--   1) "ALL"（全员通知）—— 不写明细行，跳过
--   2) JSON 数组 ["account1","account2",...] 或逗号分隔串
-- - 本脚本使用 MySQL JSON 函数解析（MySQL 5.7+ 支持 JSON_EXTRACT）
-- - 对于非标准 JSON 格式（逗号分隔串），使用循环逐条插入
-- - 幂等：每次插入前先删除该通知的旧接收人记录

-- 注意：MySQL 5.7 的 JSON_TABLE 不可用，这里用存储过程逐条解析
-- 如果 receive_list 是标准 JSON 数组格式，可以直接用 JSON_EXTRACT

DELIMITER $$

-- 存储过程：展开单个通知的接收人列表
DROP PROCEDURE IF EXISTS `expand_notice_receivers`$$
CREATE PROCEDURE `expand_notice_receivers`()
BEGIN
    DECLARE v_done INT DEFAULT 0;
    DECLARE v_notice_id INT;
    DECLARE v_receive_list TEXT;
    DECLARE cur CURSOR FOR
        SELECT id, receive_list
        FROM notice
        WHERE receive_list IS NOT NULL
          AND TRIM(receive_list) != ''
          AND UPPER(TRIM(receive_list)) != 'ALL'
          AND NOT EXISTS (
              SELECT 1 FROM notice_receiver WHERE notice_id = notice.id LIMIT 1
          );
    DECLARE CONTINUE HANDLER FOR NOT FOUND SET v_done = 1;

    OPEN cur;
    read_loop: LOOP
        FETCH cur INTO v_notice_id, v_receive_list;
        IF v_done = 1 THEN
            LEAVE read_loop;
        END IF;

        -- 清理旧数据（幂等）
        DELETE FROM notice_receiver WHERE notice_id = v_notice_id;

        -- 尝试 JSON 数组解析
        -- receive_list 格式: ["account1","account2"] 或 account1,account2
        SET v_receive_list = TRIM(v_receive_list);

        -- 去除首尾方括号（如有）
        IF LEFT(v_receive_list, 1) = '[' AND RIGHT(v_receive_list, 1) = ']' THEN
            SET v_receive_list = SUBSTRING(v_receive_list, 2, CHAR_LENGTH(v_receive_list) - 2);
        END IF;

        -- 替换引号为空，按逗号分隔
        SET v_receive_list = REPLACE(REPLACE(v_receive_list, '"', ''), '''', '');

        -- 逐条插入
        -- 简单实现：用 FIND_IN_SET 不适用于变量，改用临时表
        BEGIN
            DECLARE v_pos INT DEFAULT 1;
            DECLARE v_account VARCHAR(64);
            DECLARE v_remaining TEXT;
            SET v_remaining = v_receive_list;

            WHILE v_remaining IS NOT NULL AND TRIM(v_remaining) != '' DO
                IF LOCATE(',', v_remaining) > 0 THEN
                    SET v_account = TRIM(SUBSTRING_INDEX(v_remaining, ',', 1));
                    SET v_remaining = SUBSTRING(v_remaining, LOCATE(',', v_remaining) + 1);
                ELSE
                    SET v_account = TRIM(v_remaining);
                    SET v_remaining = NULL;
                END IF;

                IF v_account != '' AND v_account IS NOT NULL THEN
                    INSERT INTO notice_receiver (notice_id, account, receive_type, create_time)
                    VALUES (v_notice_id, v_account, 1, NOW());
                END IF;
            END WHILE;
        END;
    END LOOP;

    CLOSE cur;
END$$

DELIMITER ;

-- 执行存储过程
CALL expand_notice_receivers();

-- 清理临时存储过程
DROP PROCEDURE IF EXISTS `expand_notice_receivers`;

-- ============================================================
-- 回填结果验证查询（执行后手动检查）
-- ============================================================

-- 检查1：sch_id 回填覆盖率
-- SELECT
--     COUNT(*) AS total,
--     SUM(CASE WHEN sch_id IS NOT NULL THEN 1 ELSE 0 END) AS sch_id_filled,
--     SUM(CASE WHEN sch_id IS NULL THEN 1 ELSE 0 END) AS sch_id_null
-- FROM notice;

-- 检查2：notice_receiver 展开行数
-- SELECT COUNT(*) FROM notice_receiver;

-- 检查3：未展开的通知（receive_list 非空非 ALL 但 receiver 表无记录）
-- SELECT n.id, n.receive_list
-- FROM notice n
-- LEFT JOIN notice_receiver r ON r.notice_id = n.id
-- WHERE n.receive_list IS NOT NULL
--   AND TRIM(n.receive_list) != ''
--   AND UPPER(TRIM(n.receive_list)) != 'ALL'
--   AND r.id IS NULL;