from engine.scenarios import DEFAULT_SCENARIOS, ScenarioService


class TestScenarioService:
    def test_baseline(self, sample_model):
        service = ScenarioService(sample_model)
        result = service.apply(DEFAULT_SCENARIOS["baseline"], months=6)
        assert result["scenario"] == "baseline"
        assert result["total_balance"] is not None

    def test_compare_returns_three(self, sample_model):
        service = ScenarioService(sample_model)
        results = service.compare(months=6)
        assert "baseline" in results
        assert "optimistic" in results
        assert "pessimistic" in results

    def test_what_if(self, sample_model):
        service = ScenarioService(sample_model)
        result = service.what_if(income_mult=1.2, expense_mult=0.9, months=6)
        assert result["scenario"] == "what-if"