import pytest
from engine.portfolio import PortfolioManager

@pytest.fixture
def pm():
    return PortfolioManager(initial_capital=200.0)

def test_initial_state(pm):
    assert pm.cash == 200.0
    assert pm.positions == {}
    assert pm.trades == []

def test_buy(pm):
    pm.buy("BTCUSDT", price=40000.0, score=85)
    assert "BTCUSDT" in pm.positions
    assert pm.cash < 200.0
    assert len(pm.trades) == 1
    assert pm.trades[0]["side"] == "BUY"

def test_buy_size_by_score(pm):
    pm.buy("SOLUSDT", price=140.0, score=75)
    assert abs(pm.trades[0]["amount_usd"] - 30.0) < 0.01

def test_buy_respects_max_positions(pm):
    for i, coin in enumerate(["A", "B", "C", "D", "E"]):
        pm.buy(f"{coin}USDT", price=10.0, score=80)
    pm.buy("FUSDT", price=10.0, score=80)
    assert len(pm.positions) == 5

def test_buy_respects_min_position(pm):
    pm.cash = 10.0
    pm.buy("BTCUSDT", price=40000.0, score=85)
    assert "BTCUSDT" not in pm.positions

def test_sell_full(pm):
    pm.buy("ETHUSDT", price=3500.0, score=80)
    invested = pm.positions["ETHUSDT"]["invested_usd"]
    pm.sell("ETHUSDT", price=3800.0, reason="signal")
    assert "ETHUSDT" not in pm.positions
    assert pm.cash > 200.0 - invested

def test_stop_loss(pm):
    pm.buy("DOGEUSDT", price=0.10, score=80)
    pm.check_exit("DOGEUSDT", current_price=0.091)
    assert "DOGEUSDT" not in pm.positions

def test_take_profit_partial(pm):
    pm.buy("SOLUSDT", price=100.0, score=80)
    qty_before = pm.positions["SOLUSDT"]["quantity"]
    pm.check_exit("SOLUSDT", current_price=116.0)
    assert pm.positions["SOLUSDT"]["quantity"] < qty_before

def test_take_profit_full(pm):
    pm.buy("SOLUSDT", price=100.0, score=80)
    pm.check_exit("SOLUSDT", current_price=126.0)
    assert "SOLUSDT" not in pm.positions

def test_pnl_calculation(pm):
    pm.buy("ETHUSDT", price=3500.0, score=80)
    pnl = pm.get_portfolio_value({"ETHUSDT": 3800.0})
    assert pnl["total_pnl"] > 0
    assert pnl["total_value"] > 200.0