"""
Unit tests for TradingPortfolio.
"""
from decimal import Decimal
from datetime import date

from app.services.backtest.trading_portfolio import TradingPortfolio


def test_initial_state():
    tp = TradingPortfolio(Decimal("10000000"))
    assert tp.cash == Decimal("10000000")
    assert tp.investable_capital == Decimal("7000000")
    assert len(tp.positions) == 0


def test_enter_position():
    tp = TradingPortfolio(Decimal("10000000"))
    txn = tp.enter_position(
        ticker="005930",
        price=Decimal("70000"),
        date=date(2024, 1, 2),
        commission_rate=Decimal("0.00015"),
        slippage_rate=Decimal("0.001"),
    )
    assert txn is not None
    assert txn.action == "buy"
    assert "005930" in tp.positions
    pos = tp.positions["005930"]
    assert pos.entry_price == Decimal("70000")
    assert pos.stop_loss == Decimal("67900")  # -3%
    assert pos.target1 == Decimal("73500")  # +5%
    assert pos.target2 == Decimal("77000")  # +10%


def test_max_positions():
    tp = TradingPortfolio(Decimal("10000000"), max_positions=2)
    tp.enter_position("A", Decimal("1000"), date(2024, 1, 2), Decimal("0"), Decimal("0"))
    tp.enter_position("B", Decimal("1000"), date(2024, 1, 2), Decimal("0"), Decimal("0"))
    txn = tp.enter_position("C", Decimal("1000"), date(2024, 1, 2), Decimal("0"), Decimal("0"))
    assert txn is None
    assert len(tp.positions) == 2


def test_stop_loss_exit():
    tp = TradingPortfolio(Decimal("10000000"))
    tp.enter_position("005930", Decimal("70000"), date(2024, 1, 2), Decimal("0"), Decimal("0"))
    exits = tp.check_exits(
        date=date(2024, 1, 3),
        prices={"005930": Decimal("67000")},
        commission_rate=Decimal("0"),
        slippage_rate=Decimal("0"),
    )
    assert len(exits) == 1
    assert exits[0].action == "sell"
    assert "005930" not in tp.positions


def test_partial_take_profit():
    tp = TradingPortfolio(Decimal("10000000"))
    tp.enter_position("005930", Decimal("70000"), date(2024, 1, 2), Decimal("0"), Decimal("0"))
    pos = tp.positions["005930"]
    initial_shares = pos.shares

    exits = tp.check_exits(
        date=date(2024, 1, 10),
        prices={"005930": Decimal("73500")},
        commission_rate=Decimal("0"),
        slippage_rate=Decimal("0"),
    )
    assert len(exits) == 1
    assert exits[0].action == "partial_sell"
    assert exits[0].shares == initial_shares // 2
    assert "005930" in tp.positions
    assert tp.positions["005930"].stop_loss == Decimal("70000")


def test_full_take_profit():
    tp = TradingPortfolio(Decimal("10000000"))
    tp.enter_position("005930", Decimal("70000"), date(2024, 1, 2), Decimal("0"), Decimal("0"))
    tp.check_exits(
        date=date(2024, 1, 10),
        prices={"005930": Decimal("73500")},
        commission_rate=Decimal("0"),
        slippage_rate=Decimal("0"),
    )
    exits = tp.check_exits(
        date=date(2024, 1, 15),
        prices={"005930": Decimal("77000")},
        commission_rate=Decimal("0"),
        slippage_rate=Decimal("0"),
    )
    assert len(exits) == 1
    assert exits[0].action == "sell"
    assert "005930" not in tp.positions


def test_trailing_stop_after_partial():
    tp = TradingPortfolio(Decimal("10000000"))
    tp.enter_position("005930", Decimal("70000"), date(2024, 1, 2), Decimal("0"), Decimal("0"))
    tp.check_exits(
        date=date(2024, 1, 10),
        prices={"005930": Decimal("73500")},
        commission_rate=Decimal("0"),
        slippage_rate=Decimal("0"),
    )
    # After partial sell, stop should be at entry (70000)
    assert tp.positions["005930"].stop_loss == Decimal("70000")
    # Price rises to +8%, stop stays at entry
    tp.check_exits(
        date=date(2024, 1, 12),
        prices={"005930": Decimal("75600")},
        commission_rate=Decimal("0"),
        slippage_rate=Decimal("0"),
    )
    assert tp.positions["005930"].stop_loss == Decimal("70000")


def test_cash_reserve():
    tp = TradingPortfolio(Decimal("10000000"), cash_reserve_ratio=Decimal("0.3"))
    assert tp.investable_capital == Decimal("7000000")


def test_get_portfolio_value():
    tp = TradingPortfolio(Decimal("10000000"))
    tp.enter_position("005930", Decimal("70000"), date(2024, 1, 2), Decimal("0"), Decimal("0"))
    value = tp.get_value({"005930": Decimal("75000")})
    assert value > Decimal("10000000")


def test_duplicate_entry_rejected():
    tp = TradingPortfolio(Decimal("10000000"))
    tp.enter_position("005930", Decimal("70000"), date(2024, 1, 2), Decimal("0"), Decimal("0"))
    txn = tp.enter_position("005930", Decimal("70000"), date(2024, 1, 3), Decimal("0"), Decimal("0"))
    assert txn is None