import numpy as np
import pytest

from market_agents.exchange.accounts import Account
from market_agents.exchange.engine import AssetSpec, Exchange, ExchangeConfig


@pytest.fixture
def exchange():
    ex = Exchange([AssetSpec(asset=0, name="A0")], ExchangeConfig(taker_fee_bps=2.0, maker_fee_bps=0.0, min_latency=0.05),
                  np.random.default_rng(0), {0: 20000})
    for i in range(4):
        ex.register(Account(agent_id=i, cash=1_000_000, positions={0: 100}), latency=0.1 * (i + 1))
    return ex