"""S8-T01: Sweep engine tests."""

import pytest

from remodel_engine.scenarios.sweep import (
    SweepParam,
    TornadoEntry,
    run_sweep,
    run_tornado,
)
from remodel_engine.schemas.scenario import ScenarioInput


def _base_inputs() -> ScenarioInput:
    return ScenarioInput()


def test_empty_sweep_returns_base() -> None:
    inp = _base_inputs()
    results = run_sweep(inp, [])
    assert len(results) == 1
    assert results[0].status == "success"


def test_single_axis_sweep() -> None:
    inp = _base_inputs()
    param = SweepParam("commercial.tariff_inr_per_kwh", [3.5, 4.0, 4.5])
    results = run_sweep(inp, [param], max_workers=1)
    assert len(results) == 3
    tariffs = [r.param_values["commercial.tariff_inr_per_kwh"] for r in results]
    assert sorted(tariffs) == [3.5, 4.0, 4.5]


def test_cartesian_sweep_two_axes() -> None:
    inp = _base_inputs()
    params = [
        SweepParam("commercial.tariff_inr_per_kwh", [3.5, 4.5]),
        SweepParam("debt.interest_rate_annual", [0.09, 0.11]),
    ]
    results = run_sweep(inp, params, max_workers=2)
    assert len(results) == 4  # 2 * 2
    assert all(r.status == "success" for r in results)


def test_sweep_result_has_kpis() -> None:
    inp = _base_inputs()
    param = SweepParam("commercial.tariff_inr_per_kwh", [4.0])
    results = run_sweep(inp, [param], max_workers=1)
    assert results[0].kpis is not None


def test_sweep_invalid_path_marks_failed() -> None:
    inp = _base_inputs()
    param = SweepParam("nonexistent.field", [1.0])
    results = run_sweep(inp, [param], max_workers=1)
    assert results[0].status == "failed"
    assert results[0].error is not None


def test_tornado_returns_sorted_entries() -> None:
    inp = _base_inputs()
    entries = run_tornado(inp, kpi_key="lcoe_inr_per_kwh", max_workers=2)
    assert len(entries) > 0
    swings = [e.swing for e in entries]
    assert swings == sorted(swings, reverse=True)


def test_tornado_entry_swing_correct() -> None:
    entry = TornadoEntry(
        param_name="Test",
        low_value=0.09,
        high_value=0.12,
        base_kpi=0.18,
        low_kpi=0.20,
        high_kpi=0.15,
    )
    assert entry.swing == pytest.approx(0.05, abs=1e-6)