"""NAS 端：全量替换单张小表（DROP + CREATE + INSERT），幂等可重跑。

用于 constituent_unified / bs_adjust_factor 等小表。
- 纯 sqlite3 标准库，零第三方依赖（NAS 宿主 Python 3.8 也能跑）。
- DROP IF EXISTS + 权威 schema 重建 + INSERT：每次全量替换，重跑安全。
- 权威 schema（含主键/约束）硬编码在此，NAS 副本对齐 VPS。

用法:
    python merge_table.py --db /volume1/.../quant_trading.db --inc /tmp/t.db --table constituent_unified
"""
import argparse
import sqlite3

# 权威 schema（对齐 VPS quant_trading.db）。新增表在此登记。
SCHEMAS = {
    "constituent_unified": (
        "CREATE TABLE constituent_unified("
        "index_code TEXT, code TEXT, code_name TEXT, source TEXT,"
        "in_current INT, was_removed INT)"
    ),
    "bs_adjust_factor": (
        "CREATE TABLE bs_adjust_factor("
        "code TEXT NOT NULL, dividOperateDate TEXT NOT NULL,"
        "foreAdjustFactor REAL, backAdjustFactor REAL, adjustFactor REAL,"
        "PRIMARY KEY (code, dividOperateDate))"
    ),
}
# 列名（与源表对齐，用于 INSERT 列顺序）。
COLUMNS = {
    "constituent_unified":
        "index_code,code,code_name,source,in_current,was_removed",
    "bs_adjust_factor":
        "code,dividOperateDate,foreAdjustFactor,backAdjustFactor,adjustFactor",
}
# 额外索引（主键自带的不列）。
INDEXES = {
    "constituent_unified": [
        "CREATE INDEX IF NOT EXISTS idx_cu_index ON constituent_unified(index_code)",
        "CREATE INDEX IF NOT EXISTS idx_cu_code ON constituent_unified(code)",
    ],
    "bs_adjust_factor": [],
}


def main():
    ap = argparse.ArgumentParser(description="全量替换单张小表进 NAS 副本")
    ap.add_argument("--db", required=True, help="NAS quant_trading.db 路径")
    ap.add_argument("--inc", required=True, help="增量 sqlite 路径")
    ap.add_argument("--table", required=True, help="表名")
    args = ap.parse_args()
    tbl = args.table
    if tbl not in SCHEMAS:
        raise SystemExit("unknown table %s; add schema/columns first" % tbl)
    cols = COLUMNS[tbl]

    conn = sqlite3.connect(args.db)
    cur = conn.cursor()
    for p in ("PRAGMA journal_mode=WAL", "PRAGMA synchronous=NORMAL"):
        cur.execute(p)
    cur.execute("ATTACH DATABASE ? AS inc", (args.inc,))

    inc_count = cur.execute(
        "SELECT COUNT(*) FROM inc.[%s]" % tbl).fetchone()[0]
    cur.execute("DROP TABLE IF EXISTS main.[%s]" % tbl)
    cur.execute(SCHEMAS[tbl])
    for idx in INDEXES.get(tbl, []):
        cur.execute(idx)
    cur.execute(
        "INSERT INTO main.[%s](%s) SELECT %s FROM inc.[%s]" % (tbl, cols, cols, tbl)
    )
    conn.commit()
    after = cur.execute(
        "SELECT COUNT(*) FROM main.[%s]" % tbl).fetchone()[0]
    conn.close()
    print("REPLACED table=%s inc=%d after=%d" % (tbl, inc_count, after))


if __name__ == "__main__":
    main()