from __future__ import annotations

from collections.abc import Callable
from dataclasses import dataclass
from typing import ClassVar

from app.simulation.core.medium import GasMedium, IdealGasMedium
from app.simulation.core.peng_robinson import HELIUM_PR, PengRobinsonFluid


@dataclass(frozen=True)
class AmesimIdealAirMedium(IdealGasMedium):
    """AMESim air properties evaluated with the ideal-gas method.

    Substance identity and property method are part of the concrete Python
    type.  A future air correlation or helium Peng-Robinson implementation can
    therefore coexist as a sibling type without turning ``gi`` into a fluid
    enumeration.
    """

    SUBSTANCE_ID: ClassVar[str] = "air"
    PROPERTY_METHOD_ID: ClassVar[str] = "ideal_gas"

    name: str = "AMESimAirIdealGas"
    R_gas: float = 287.0
    cp_ref: float = 1005.0
    T_ref: float = 300.0
    cp_slope: float = 0.0
    viscosity_ref: float = 1.82e-5
    viscosity_T_ref: float = 293.15
    sutherland_constant: float = 110.4


@dataclass(frozen=True)
class AmesimHeliumPengRobinsonMedium(IdealGasMedium):
    """AMESim helium with a Peng-Robinson mechanical equation of state.

    The pressure-density-temperature relation is evaluated by the shared
    ``HELIUM_PR`` fluid.  The first public AMESim port keeps the committed
    constant-heat-capacity caloric model so it can be consumed through the
    same :class:`GasMedium` contract as ideal-gas air.
    """

    SUBSTANCE_ID: ClassVar[str] = "helium"
    PROPERTY_METHOD_ID: ClassVar[str] = "peng_robinson"
    fluid: ClassVar[PengRobinsonFluid] = HELIUM_PR

    name: str = "AMESimHeliumPengRobinson"
    R_gas: float = HELIUM_PR.specific_gas_constant
    cp_ref: float = 5193.0
    T_ref: float = 293.15
    cp_slope: float = 0.0
    viscosity_ref: float = 1.96e-5
    viscosity_T_ref: float = 293.15
    sutherland_constant: float = 79.4

    @property
    def cv(self) -> float:
        return 3116.0

    def cv_at_temperature(self, T: float) -> float:
        del T
        return self.cv

    def density(self, p: float, T: float) -> float:
        return self.fluid.density(p, T)

    def pressure(self, m: float, T: float, V: float) -> float:
        if V <= 0.0:
            raise ValueError("Volume must stay positive.")
        return self.fluid.pressure_from_density(T, m / V)


@dataclass(frozen=True)
class AmesimGasPropertyModelSpec:
    """A selectable calculation method for one AMESim gas substance."""

    value: int
    label: str
    method_id: str
    factory: Callable[[], GasMedium]
    eos_type: int

    def build_medium(self) -> GasMedium:
        return self.factory()


AMESIM_AIR_IDEAL_GAS_PROPERTY_MODEL = 0
AMESIM_AIR_PROPERTY_MODELS = (
    AmesimGasPropertyModelSpec(
        value=AMESIM_AIR_IDEAL_GAS_PROPERTY_MODEL,
        label="理想气体",
        method_id=AmesimIdealAirMedium.PROPERTY_METHOD_ID,
        factory=AmesimIdealAirMedium,
        eos_type=1,
    ),
)


AMESIM_HELIUM_PENG_ROBINSON_PROPERTY_MODEL = 0
AMESIM_HELIUM_PROPERTY_MODELS = (
    AmesimGasPropertyModelSpec(
        value=AMESIM_HELIUM_PENG_ROBINSON_PROPERTY_MODEL,
        label="Peng–Robinson",
        method_id=AmesimHeliumPengRobinsonMedium.PROPERTY_METHOD_ID,
        factory=AmesimHeliumPengRobinsonMedium,
        eos_type=6,
    ),
)