"""PositionLedger 单标的持仓对象测试（raw 计均价、T+1 冻结）。"""
import pytest

from sanguo_trader.position_ledger import PositionLedger


def test_new_position_empty():
    p = PositionLedger(symbol="600000")
    assert p.volume == 0
    assert p.frozen == 0
    assert p.avg_price == 0.0
    assert p.available == 0


def test_buy_sets_avg_price_and_freezes():
    p = PositionLedger(symbol="600000")
    p.apply_buy(price=10.0, volume=100)
    assert p.volume == 100
    assert p.frozen == 100          # T+1：买入当日冻结
    assert p.available == 0         # 当日不可卖
    assert p.avg_price == 10.0


def test_avg_price_weighted_on_add():
    p = PositionLedger(symbol="600000")
    p.apply_buy(10.0, 100)
    p.unfreeze()                    # 次日解冻
    p.apply_buy(12.0, 100)
    assert p.avg_price == 11.0      # (10*100 + 12*100)/200
    assert p.volume == 200
    # 新买的 100 又被冻结（T+1）
    assert p.frozen == 100
    assert p.available == 100


def test_cannot_sell_frozen():
    p = PositionLedger(symbol="600000")
    p.apply_buy(10.0, 100)
    assert p.frozen == 100
    assert p.available == 0         # 当日不可卖


def test_unfreeze_makes_available():
    p = PositionLedger(symbol="600000")
    p.apply_buy(10.0, 100)
    p.unfreeze()
    assert p.frozen == 0
    assert p.available == 100


def test_sell_reduces_volume():
    p = PositionLedger(symbol="600000")
    p.apply_buy(10.0, 200)
    p.unfreeze()
    p.apply_sell(11.0, 100)
    assert p.volume == 100
    assert p.available == 100


def test_sell_odd_lot_allowed():
    """A 股卖出允许零股（退出持仓的基本操作）。"""
    p = PositionLedger(symbol="600000")
    p.apply_buy(10.0, 200)
    p.unfreeze()
    p.apply_sell(11.0, 50)          # 50 股零股
    assert p.volume == 150


def test_sell_over_available_raises():
    p = PositionLedger(symbol="600000")
    p.apply_buy(10.0, 100)
    p.unfreeze()
    with pytest.raises(ValueError, match="available"):
        p.apply_sell(11.0, 200)


def test_sell_frozen_raises():
    """T+1：当日买入冻结，卖出冻结量必报错。"""
    p = PositionLedger(symbol="600000")
    p.apply_buy(10.0, 100)
    with pytest.raises(ValueError):
        p.apply_sell(11.0, 50)


def test_clear_position_avg_price_resets():
    p = PositionLedger(symbol="600000")
    p.apply_buy(10.0, 100)
    p.unfreeze()
    p.apply_sell(11.0, 100)
    assert p.volume == 0
    assert p.avg_price == 0.0