from datetime import date, timedelta
from decimal import Decimal

import pytest

from grid_trading.domain.models import Instrument, Trade, TradeGroup, TradeSide
from grid_trading.services.trading_service import TradingService


def test_service_creates_default_account_and_computes_summary(tmp_path):
    service = TradingService(tmp_path / "grid.db")
    service.ensure_defaults()
    account = service.get_active_account()
    assert account.name == "默认账户"

    account = service.save_account(account.__class__(id=account.id, name="主账户", initial_cash=Decimal("100000")))
    instrument = service.add_instrument(
        Instrument(id=None, code="510300", name="沪深300ETF", market="ETF", manual_price=Decimal("4.00"))
    )
    service.save_trade(
        Trade(
            id=None,
            account_id=account.id,
            instrument_id=instrument.id,
            trade_date=date(2026, 7, 7),
            side=TradeSide.BUY,
            price=Decimal("3.90"),
            quantity=1000,
            commission=Decimal("5"),
            trade_group=TradeGroup.GRID,
        )
    )
    service.save_trade(
        Trade(
            id=None,
            account_id=account.id,
            instrument_id=instrument.id,
            trade_date=date(2026, 7, 8),
            side=TradeSide.SELL,
            price=Decimal("4.10"),
            quantity=500,
            commission=Decimal("5"),
            stamp_tax=Decimal("1.03"),
            trade_group=TradeGroup.GRID,
        )
    )

    positions = service.get_position_summaries(as_of=date(2026, 7, 8))
    summary = service.get_account_summary(as_of=date(2026, 7, 8))

    assert len(positions) == 1
    assert positions[0].total_quantity == 500
    assert positions[0].grid_profit == Decimal("91.47")
    assert summary.cash == Decimal("98138.97")
    assert summary.market_value == Decimal("2000.00")
    assert summary.total_assets == Decimal("100138.97")


def test_service_validates_lot_size_and_available_sell_quantity(tmp_path):
    service = TradingService(tmp_path / "grid.db")
    service.ensure_defaults()
    account = service.get_active_account()
    instrument = service.add_instrument(Instrument(id=None, code="600000", name="浦发银行"))

    with pytest.raises(ValueError, match="100"):
        service.save_trade(
            Trade(
                id=None,
                account_id=account.id,
                instrument_id=instrument.id,
                trade_date=date(2026, 7, 8),
                side=TradeSide.BUY,
                price=Decimal("10"),
                quantity=50,
                trade_group=TradeGroup.BASE,
            )
        )

    service.save_trade(
        Trade(
            id=None,
            account_id=account.id,
            instrument_id=instrument.id,
            trade_date=date(2026, 7, 8),
            side=TradeSide.BUY,
            price=Decimal("10"),
            quantity=100,
            trade_group=TradeGroup.BASE,
        )
    )

    with pytest.raises(ValueError, match="T\\+1"):
        service.save_trade(
            Trade(
                id=None,
                account_id=account.id,
                instrument_id=instrument.id,
                trade_date=date(2026, 7, 8),
                side=TradeSide.SELL,
                price=Decimal("10.1"),
                quantity=100,
                trade_group=TradeGroup.BASE,
            )
        )

    service.save_trade(
        Trade(
            id=None,
            account_id=account.id,
            instrument_id=instrument.id,
            trade_date=date(2026, 7, 8) - timedelta(days=1),
            side=TradeSide.BUY,
            price=Decimal("9.9"),
            quantity=100,
            trade_group=TradeGroup.BASE,
        )
    )
    saved_sell = service.save_trade(
        Trade(
            id=None,
            account_id=account.id,
            instrument_id=instrument.id,
            trade_date=date(2026, 7, 8),
            side=TradeSide.SELL,
            price=Decimal("10.1"),
            quantity=100,
            trade_group=TradeGroup.BASE,
        )
    )

    assert saved_sell.id is not None