"""期期到期结算指数：虚值 Call fill=0 不得反推成行权价。"""

from __future__ import annotations

from app.api.trades import _infer_settle_index


def test_otm_call_zero_fill_does_not_become_strike() -> None:
    g = {
        "hedge_mode": "option_option",
        "option_side": "call",
        "option2_side": "put",
        "strike": 1920.0,
        "strike2": 1890.0,
        "settle_index_px": None,
    }
    fills = [
        {"leg": "option", "action": "close", "fill_px": 0.0, "slip": 0},
        {"leg": "option2", "action": "close", "fill_px": 0.0, "slip": 0},
    ]
    assert _infer_settle_index(g, fills) is None


def test_itm_put_fill_infers_settle_near_1875() -> None:
    g = {
        "hedge_mode": "option_option",
        "option_side": "call",
        "option2_side": "put",
        "strike": 1920.0,
        "strike2": 1920.0,
        "settle_index_px": None,
    }
    fills = [
        {"leg": "option", "action": "close", "fill_px": 0.0, "slip": 0},
        {"leg": "option2", "action": "close", "fill_px": 45.0, "slip": 0},
    ]
    # put intrinsic 45 → settle = 1920 - 45 = 1875
    assert _infer_settle_index(g, fills) == 1875.0


def test_stored_settle_wins() -> None:
    g = {
        "option_side": "call",
        "strike": 1920.0,
        "settle_index_px": 1875.2,
    }
    fills = [{"leg": "option", "action": "close", "fill_px": 0.0, "slip": 0}]
    assert _infer_settle_index(g, fills) == 1875.2