"""Shared fixtures for the Optimiser test files: distinguishable Simulation
Overlays (so a stub scorer can attribute a true gain per measure kind), the
ScoredOption builder, the additive per-kind stub scorer, and the forced
ventilation Measure Dependency edge.

Fixture values stay domain-plausible: overlay heating codes are real SAP
Table 4a codes (104 = mains-gas combi boiler, heat pumps carry a PCDF index),
and tests price measures at realistic magnitudes (a CWI around £1,000, an
ASHP around £8,000)."""

from __future__ import annotations

from typing import Optional, Sequence

from datatypes.epc.domain.epc_property_data import (
    BuildingPartIdentifier,
    EpcPropertyData,
)
from domain.modelling.measure_type import MeasureType
from domain.modelling.optimisation.optimiser import MeasureDependency, ScoredOption
from domain.modelling.recommendation import Cost, MeasureOption
from domain.modelling.scoring.package_scorer import Score
from domain.modelling.simulation import (
    BuildingPartOverlay,
    EpcSimulation,
    GlazingOverlay,
    HeatingOverlay,
    VentilationOverlay,
)

WALL_OVERLAY = EpcSimulation(
    building_parts={
        BuildingPartIdentifier.MAIN: BuildingPartOverlay(wall_insulation_type=2)
    }
)
ROOF_OVERLAY = EpcSimulation(
    building_parts={
        BuildingPartIdentifier.MAIN: BuildingPartOverlay(roof_insulation_thickness=300)
    }
)
FLOOR_OVERLAY = EpcSimulation(
    building_parts={
        BuildingPartIdentifier.MAIN: BuildingPartOverlay(floor_insulation_thickness=100)
    }
)
GLAZING_OVERLAY = EpcSimulation(glazing=GlazingOverlay(glazing_type=2))
VENT_OVERLAY = EpcSimulation(
    ventilation=VentilationOverlay(mechanical_ventilation_kind="EXTRACT_OR_PIV_OUTSIDE")
)
# SAP Table 4a code 104: a mains-gas combi boiler.
BOILER_OVERLAY = EpcSimulation(heating=HeatingOverlay(sap_main_heating_code=104))
# Heat pumps are expressed as a PCDF product index, as the generator emits them.
ASHP_OVERLAY = EpcSimulation(heating=HeatingOverlay(main_heating_index_number=13000))

_WALL_TRIGGERS: frozenset[MeasureType] = frozenset(
    {MeasureType.CAVITY_WALL_INSULATION, MeasureType.EXTERNAL_WALL_INSULATION}
)


def scored_option(
    measure_type: str,
    *,
    gain: float,
    cost: float,
    overlay: Optional[EpcSimulation] = None,
) -> ScoredOption:
    """A one-Option fixture: ``gain`` is the role-1 warm-start signal, ``cost``
    the total install cost. Omit ``overlay`` where the test never re-scores."""
    return ScoredOption(
        option=MeasureOption(
            measure_type=MeasureType(measure_type),
            description=measure_type,
            overlay=overlay if overlay is not None else EpcSimulation(),
            cost=Cost(total=cost, contingency_rate=0.0),
        ),
        sap_gain=gain,
    )


class StubScorer:
    """A deterministic stand-in for PackageScorer: the package SAP is a base
    plus a fixed *true* gain per measure kind present (detected by overlay
    field), decoupled from the role-1 signal — so selection, repair and the
    two-phase split are exercised without the calculator. Kinds a test does
    not use default to 0."""

    def __init__(
        self,
        *,
        base: float,
        wall: float = 0.0,
        roof: float = 0.0,
        floor: float = 0.0,
        heating: float = 0.0,
        vent: float = 0.0,
    ) -> None:
        self._base = base
        self._wall = wall
        self._roof = roof
        self._floor = floor
        self._heating = heating
        self._vent = vent

    def score(
        self, baseline: EpcPropertyData, simulations: Sequence[EpcSimulation]
    ) -> Score:
        sap = self._base
        for sim in simulations:
            if sim.heating is not None:
                sap += self._heating
            if sim.ventilation is not None:
                sap += self._vent
            for part in sim.building_parts.values():
                if part.wall_insulation_type is not None:
                    sap += self._wall
                if part.roof_insulation_thickness is not None:
                    sap += self._roof
                if part.floor_insulation_thickness is not None:
                    sap += self._floor
        return Score(
            sap_continuous=sap, co2_kg_per_yr=0.0, primary_energy_kwh_per_yr=0.0
        )


def selected_types(selection: Sequence[ScoredOption]) -> set[str]:
    return {scored.option.measure_type for scored in selection}


def ventilation_dependency(
    *, cost: float, triggers: frozenset[MeasureType] = _WALL_TRIGGERS
) -> MeasureDependency:
    """A forced 'airtightness requires ventilation' edge for the tests."""
    return MeasureDependency(
        triggers=triggers,
        required=ScoredOption(
            option=MeasureOption(
                measure_type=MeasureType.MECHANICAL_VENTILATION,
                description="mechanical_ventilation",
                overlay=VENT_OVERLAY,
                cost=Cost(total=cost, contingency_rate=0.0),
            ),
            sap_gain=0.0,  # placeholder; optimise_package scores the real signal
        ),
    )