-- 在 meeting_im 共库执行。用于并发安全地生成每个租户的 im_users.account_no。
CREATE TABLE IF NOT EXISTS im_user_account_sequences (
    tenant_id BIGINT NOT NULL,
    id TINYINT UNSIGNED NOT NULL,
    next_value INT UNSIGNED NOT NULL,
    updated_at DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3)
        ON UPDATE CURRENT_TIMESTAMP(3),
    PRIMARY KEY (tenant_id, id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

-- 如果历史脚本已经创建过单库版 PRIMARY KEY(id)，需要先改成共库主键。
ALTER TABLE im_user_account_sequences
    DROP PRIMARY KEY,
    ADD PRIMARY KEY (tenant_id, id);

-- 兼容已有用户数据，从每个租户当前最大账号编号继续递增，账号编号最小为 1000。
INSERT INTO im_user_account_sequences (tenant_id, id, next_value)
SELECT tenant_id, 1, GREATEST(COALESCE(MAX(account_no), 999), 999)
FROM im_users
WHERE tenant_id > 0
GROUP BY tenant_id
ON DUPLICATE KEY UPDATE
    next_value = GREATEST(next_value, VALUES(next_value));

-- 如果当前租户暂时还没有用户，也要先塞一行，否则新注册无法生成账号编号。
INSERT IGNORE INTO im_user_account_sequences (tenant_id, id, next_value)
SELECT id, 1, 999
FROM hotgo.im_tenant
WHERE state = 1;