"""HistoricConditioning resolves an expired Historic EPC's stable attributes
into the cohort's code spaces (ADR-0054).

Only stable attributes are resolved — volatile ones (heating system, glazing,
PV, insulation states) never condition prediction. Every resolver degrades to
None on an unresolvable value, which leaves its cohort filter inactive.
"""

from __future__ import annotations

import dataclasses

from datatypes.epc.domain.historic_epc import HistoricEpc
from domain.epc_prediction.historic_conditioning import (
    HistoricConditioning,
    conditioning_from_historic,
)


def _hist(**overrides: str) -> HistoricEpc:
    fields = {f.name: "" for f in dataclasses.fields(HistoricEpc)}
    fields.update(overrides)
    return HistoricEpc(**fields)


def test_resolves_stable_attributes_into_cohort_code_spaces():
    # Arrange — display-text values exactly as the old register lodged them.
    record = _hist(
        property_type="House",
        built_form="Semi-Detached",
        walls_description="Cavity wall, as built, no insulation (assumed)",
        roof_description="Pitched, 100 mm loft insulation",
        construction_age_band="England and Wales: 1930-1949",
        main_fuel="mains gas (not community)",
        total_floor_area="84",
    )

    # Act
    conditioning = conditioning_from_historic(record)

    # Assert — each attribute lands in the code space its cohort filter compares.
    assert isinstance(conditioning, HistoricConditioning)
    assert conditioning.property_type == "0"
    assert conditioning.built_form == "2"
    assert conditioning.wall_construction == 4
    assert conditioning.roof_form == "pitched"
    assert conditioning.construction_age_band == "C"
    assert conditioning.main_fuel == 26
    assert conditioning.total_floor_area_m2 == 84.0


def test_roof_descriptions_resolve_to_form_families():
    # Arrange / Act / Assert — the FORM half of the description (before the
    # comma) maps to a family, because the API's roof_construction codes group
    # that way (7,974-cert co-occurrence sweep: 1=Flat 98%, 4/5/8=Pitched
    # 88-99%, 3=another dwelling above 100%; 7/9=another premises above per
    # the #1452 suppression fix). Insulation state is volatile and ignored.
    cases = {
        "Pitched, 250 mm loft insulation": "pitched",
        "Pitched, no insulation (assumed)": "pitched",
        "Flat, insulated (assumed)": "flat",
        "(another dwelling above)": "dwelling_above",
        "(another premises above)": "premises_above",
    }
    for text, family in cases.items():
        record = _hist(roof_description=text)
        assert conditioning_from_historic(record).roof_form == family, text
    # Unpinned forms (roof rooms, thatched) must not guess.
    assert conditioning_from_historic(
        _hist(roof_description="Roof room(s), insulated")
    ).roof_form is None
    assert conditioning_from_historic(
        _hist(roof_description="Thatched, with additional insulation")
    ).roof_form is None


def test_legacy_register_fuel_descriptions_resolve():
    # Arrange / Act / Assert — the old register lodged pre-RdSAP-17 fuels with
    # a "backwards compatibility" rider or a SAP-style prefix; they name the
    # same physical fuels (dominant in the pre-2012 dump: a 65-shard scan found
    # 636/663 unresolved values were these variants).
    cases = {
        "mains gas - this is for backwards compatibility only and should not be used": 26,
        "electricity - this is for backwards compatibility only and should not be used": 29,
        "LPG - this is for backwards compatibility only and should not be used": 27,
        "oil - this is for backwards compatibility only and should not be used": 28,
        "Gas: mains gas": 26,
        "Electricity: electricity, unspecified tariff": 29,
        "dual fuel - mineral + wood": 10,
    }
    for text, code in cases.items():
        record = _hist(main_fuel=text)
        assert conditioning_from_historic(record).main_fuel == code, text


def test_unresolvable_values_degrade_to_none():
    # Arrange — junk and blanks must never guess a code.
    record = _hist(
        property_type="Castle",
        built_form="Not Recorded",
        walls_description="Average thermal transmittance 0.3 W/m²K",
        construction_age_band="INVALID!",
        main_fuel="To be used only when there is no heating system",
        total_floor_area="",
    )

    # Act
    conditioning = conditioning_from_historic(record)

    # Assert
    assert conditioning.property_type is None
    assert conditioning.built_form is None
    assert conditioning.wall_construction is None
    assert conditioning.roof_form is None
    assert conditioning.construction_age_band is None
    assert conditioning.main_fuel is None
    assert conditioning.total_floor_area_m2 is None