import importlib.util
import sqlite3
from pathlib import Path


def test_backup_and_restore_snapshot(tmp_path):
    source = Path(__file__).resolve().parents[1] / 'tools' / 'backup_db.py'
    spec = importlib.util.spec_from_file_location('backup_tool', source)
    module = importlib.util.module_from_spec(spec)
    spec.loader.exec_module(module)
    instance = tmp_path / 'instance'
    instance.mkdir()
    path = instance / 'po.db'
    with sqlite3.connect(path) as db:
        db.execute('CREATE TABLE orders(id INTEGER PRIMARY KEY, amount INTEGER)')
        db.execute('INSERT INTO orders(amount) VALUES(66)')
    snapshot = module.backup_database(tmp_path)
    with sqlite3.connect(path) as db:
        db.execute('UPDATE orders SET amount=100')
    with sqlite3.connect(snapshot) as db:
        assert db.execute('PRAGMA integrity_check').fetchone()[0] == 'ok'
        assert db.execute('SELECT amount FROM orders').fetchone()[0] == 66
        with sqlite3.connect(tmp_path / 'restored.db') as restored:
            db.backup(restored)
            assert restored.execute('SELECT amount FROM orders').fetchone()[0] == 66