"""Coolant loop control models."""

from __future__ import annotations

from dataclasses import dataclass
import logging

from . import constants
from .state import CoolantLoopState

LOGGER = logging.getLogger(__name__)


@dataclass
class Pump:
    nominal_flow: float
    efficiency: float = 0.9
    spool_time: float = constants.PUMP_SPOOL_TIME

    def flow_rate(self, demand: float) -> float:
        demand = max(0.0, min(1.0, demand))
        return self.nominal_flow * (0.2 + 0.8 * demand) * self.efficiency

    def step(self, loop: CoolantLoopState, demand: float) -> None:
        loop.mass_flow_rate = self.flow_rate(demand)
        loop.pressure = 12.0 * demand + 2.0
        LOGGER.debug(
            "Pump demand=%.2f -> %.0f kg/s, pressure=%.1f MPa", demand, loop.mass_flow_rate, loop.pressure
        )