from __future__ import annotations

import unittest

from app.simulation.components.amesim.boundary.sources import AmesimPnpl01
from app.simulation.core.medium import IdealGasMedium
from app.simulation.registry import COMPONENT_MODEL_REGISTRY


class AmesimPnpl01ComponentTests(unittest.TestCase):
    def setUp(self) -> None:
        self.medium = IdealGasMedium()

    def test_default_create_preserves_zero_flow_boundary_contract(self) -> None:
        source = COMPONENT_MODEL_REGISTRY["amesim_pnpl01"].create(
            "plug_1",
            self.medium,
            {},
        )

        self.assertIsInstance(source, AmesimPnpl01)
        self.assertEqual(set(source.ports), {"port_1"})
        self.assertEqual(source.parameter_values, {})

    def test_zero_flow_residual_uses_port_mass_flow(self) -> None:
        source = AmesimPnpl01("plug_1")
        source.port_1.m_flow = 0.125

        residuals = source.pressure_flow_equation_residuals()

        self.assertEqual(len(residuals), 1)
        self.assertEqual(residuals[0].id, "plug_1:zero_mass_flow")
        self.assertEqual(residuals[0].variables, ("plug_1.port_1.m_flow",))
        self.assertEqual(residuals[0].value, 0.125)

    def test_stream_outflow_tracks_connected_enthalpy_when_available(self) -> None:
        source = AmesimPnpl01("plug_1")

        source.update_stream_outflows({"port_1": 123.0})

        self.assertEqual(source.port_1.h_outflow, 123.0)


if __name__ == "__main__":
    unittest.main()