from arbitrade.exchange.models import BookLevel
from arbitrade.market_data.order_book import OrderBook


def test_order_book_apply_and_best_levels() -> None:
    book = OrderBook()
    book.apply_bids([BookLevel(price=100.0, volume=1.0), BookLevel(price=99.5, volume=2.0)])
    book.apply_asks([BookLevel(price=100.5, volume=1.1), BookLevel(price=101.0, volume=0.9)])

    best_bid = book.best_bid()
    best_ask = book.best_ask()

    assert best_bid is not None
    assert best_ask is not None
    assert best_bid.price == 100.0
    assert best_ask.price == 100.5


def test_order_book_checksum_matches_self() -> None:
    book = OrderBook()
    book.apply_bids([BookLevel(price=100.0, volume=1.0)])
    book.apply_asks([BookLevel(price=100.5, volume=1.0)])

    checksum = book.compute_checksum()

    assert isinstance(checksum, int)
    assert checksum == book.compute_checksum()