#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""backup_db.py — VPS 本地全库备份(回滚保险)。

sqlite3 .backup 在线一致 + WAL checkpoint(TRUNCATE) + integrity_check。
所有迁移单元的前置。BAK 同机存放,可立即恢复(满足"备份能回滚搞不坏")。

注:VPS(公网)↔ NAS(内网)不直连,异地冗余需 Mac 中转(28GB 大,可选)。
此处只做 VPS 本地 .bak(核心回滚保障)。
"""
import sqlite3
import datetime
from pathlib import Path

DB = Path(r"C:\sanguo_vnpy_v2\data\quant_trading.db")
ts = datetime.date.today().strftime("%Y%m%d")
BAK = DB.parent / f"quant_trading.db.bak_{ts}"

print(f"DB : {DB}  ({DB.stat().st_size / 1024**3:.1f} GB)")
print(f"BAK: {BAK}")

src = sqlite3.connect(str(DB), timeout=120)
src.execute("PRAGMA busy_timeout = 120000")
print("WAL checkpoint(TRUNCATE)...")
print(" ", src.execute("PRAGMA wal_checkpoint(TRUNCATE)").fetchone())

if BAK.exists():
    print(f"BAK 已存在, 覆盖: {BAK}")

print("sqlite3 .backup (在线一致, 可能需几分钟)...")
with sqlite3.connect(str(BAK)) as dst:
    src.backup(dst)
src.close()

print(f"BAK 写入: {BAK.stat().st_size / 1024**3:.1f} GB")

# integrity_check on backup
chk = sqlite3.connect(str(BAK))
result = chk.execute("PRAGMA integrity_check").fetchone()[0]
chk.close()
print(f"integrity_check: {result}")
print("BACKUP DONE" if result == "ok" else "BACKUP WARNING: integrity_check 非 ok")