"""Golden tests for EXECUTION_CAPACITY_LADDER_V1 (governance/todo/v8_9_p1_adoption_plan.yaml P1-B.4).

Maps to v8.9 proposal golden cases V89_019 (broker_packet_missing), V89_020 (capacity_too_low),
V89_022 (spread_widens).
"""
from __future__ import annotations

import importlib.util
from pathlib import Path

ROOT = Path(__file__).resolve().parents[3]
MODULE_PATH = ROOT / "tools" / "build_execution_capacity_ladder_v1.py"


def _load_module():
    spec = importlib.util.spec_from_file_location("build_execution_capacity_ladder_v1", MODULE_PATH)
    module = importlib.util.module_from_spec(spec)
    assert spec.loader is not None
    spec.loader.exec_module(module)
    return module


def test_v89_019_missing_broker_packet_blocks_not_zero_capacity() -> None:
    mod = _load_module()
    order = {
        "planned_order_amount_krw": 50000000,
        "avg_trade_value_20d_krw": None,
        "intraday_trade_value_krw": 500000000,
        "orderbook_top3_depth_krw": 100000000,
        "spread_bps": 5,
    }
    result = mod.evaluate_order_capacity(order)
    assert result["gate"] == "EXECUTION_PLAN_BLOCKED"
    assert result["order_capacity_krw"] is None


def test_v89_020_planned_amount_exceeding_capacity_gets_capped() -> None:
    mod = _load_module()
    order = {
        "planned_order_amount_krw": 50000000,
        "avg_trade_value_20d_krw": 1000000000,
        "intraday_trade_value_krw": 500000000,
        "orderbook_top3_depth_krw": 100000000,
        "spread_bps": 5,
    }
    result = mod.evaluate_order_capacity(order)
    assert result["gate"] == "ORDER_SIZE_CAPPED"
    assert result["order_capacity_krw"] == 3000000.0


def test_v89_022_spread_widening_beyond_1_5x_triggers_cancel() -> None:
    mod = _load_module()
    assert mod.should_cancel_remaining_slices(16, 10) is True
    assert mod.should_cancel_remaining_slices(14, 10) is False


def test_trading_halt_blocks_regardless_of_other_fields() -> None:
    mod = _load_module()
    result = mod.evaluate_order_capacity({"planned_order_amount_krw": 50000000, "halt_status": True})
    assert result["gate"] == "EXECUTION_PLAN_BLOCKED"
    assert result["reason_code"] == "trading_halt"