"""一次性回填:RIIN Goods.status 为 NULL 的历史行(终态"已发货"订单)。

背景:RIIN 商品级 goods_status 复用平台状态枚举,COMPLETE/PAUSE 此前无映射,
约 1/3 商品行 status 被写为 NULL(mappers.py 已补映射)。本脚本按订单终态
将近似值回填;"已关闭"与非终态订单不在此列,走 riin-by-orders 重拉取真值。
幂等:只更新 status IS NULL 的行。分批提交,避免长事务。

运行:uv run python scripts/backfill_riin_goods_status.py [--dry-run] [--batch N]
"""

from __future__ import annotations

import argparse
import os

import psycopg2
from dotenv import load_dotenv

load_dotenv(os.path.join(os.path.dirname(__file__), "..", ".env"))

DEFAULT_BATCH = 50_000

SQL_COUNT = """
SELECT count(*) FROM "Goods" g
JOIN "Orders" o ON o."orderNo" = g."orderNo" AND o."createdAt" = g."createdAt"
WHERE o."systemName" = 'RIIN' AND o."systemStatus" = '已发货' AND g."status" IS NULL
"""

# ctid 分批:PostgreSQL 的 UPDATE 不支持 LIMIT,用子查询圈定每批行
SQL_BACKFILL_BATCH = """
UPDATE "Goods" g SET "status" = '已发货'
WHERE g.ctid IN (
    SELECT g2.ctid FROM "Goods" g2
    JOIN "Orders" o ON o."orderNo" = g2."orderNo" AND o."createdAt" = g2."createdAt"
    WHERE o."systemName" = 'RIIN' AND o."systemStatus" = '已发货' AND g2."status" IS NULL
    LIMIT %s
)
"""


def main() -> None:
    parser = argparse.ArgumentParser(description="回填 RIIN Goods.status NULL(已发货订单)")
    parser.add_argument("--dry-run", action="store_true", help="只统计待回填行数,不写入")
    parser.add_argument("--batch", type=int, default=DEFAULT_BATCH, help="每事务回填行数")
    args = parser.parse_args()

    conn = psycopg2.connect(os.environ["DB_DSN"])
    try:
        with conn.cursor() as cur:
            cur.execute(SQL_COUNT)
            (pending,) = cur.fetchone()
        print(f"[backfill] 待回填(status IS NULL 且订单已发货): {pending} 行")
        if args.dry_run or pending == 0:
            return

        total = 0
        while True:
            with conn.cursor() as cur:
                cur.execute(SQL_BACKFILL_BATCH, (args.batch,))
                updated = cur.rowcount
            conn.commit()
            total += updated
            print(f"[backfill] 本批 {updated} 行,累计 {total}")
            if updated < args.batch:
                break
        print(f"[backfill] 完成,共回填 {total} 行")
    finally:
        conn.close()


if __name__ == "__main__":
    main()