"""Behaviour of ``_predict_epc``'s failure modes: an EPC-less Property that
cannot be predicted must fail loudly with a *specific*, debuggable exception
(carrying the Property's identity + the cause), not a single generic
"not predictable" string. The per-property handler records ``str(exc)`` in the
SubTask output, so these messages are the operator's only debugging signal.
"""

from typing import Callable, Optional, cast
from unittest.mock import MagicMock

import pytest

from applications.modelling_e2e.errors import (
    DegeneratePredictionError,
    NoSameTypeComparablesError,
    UnresolvedPropertyTypeError,
)
from applications.modelling_e2e.handler import (
    _predict_epc,  # pyright: ignore[reportPrivateUsage]
)
from datatypes.epc.domain.epc_property_data import (
    BuildingPartIdentifier,
    EpcPropertyData,
    SapBuildingPart,
)
from domain.epc_prediction.comparable_properties import ComparableProperty
from domain.epc_prediction.epc_prediction import EpcPrediction
from domain.epc_prediction.prediction_target import (
    PredictionTarget,
    PredictionTargetAttributes,
)
from repositories.property.override_backed_prediction_attributes_reader import (
    OverrideBackedPredictionAttributesReader,
)


class _FixedAttributesReader:
    """An attributes reader that returns one fixed PredictionTargetAttributes."""

    def __init__(self, attributes: PredictionTargetAttributes) -> None:
        self._attributes = attributes

    def attributes_for(self, property_id: int) -> PredictionTargetAttributes:
        return self._attributes


def _reader(
    attributes: PredictionTargetAttributes,
) -> OverrideBackedPredictionAttributesReader:
    return cast(
        OverrideBackedPredictionAttributesReader, _FixedAttributesReader(attributes)
    )


def _no_cohort() -> Callable[[str], list[ComparableProperty]]:
    return lambda _postcode: []


def _no_broaden() -> Callable[[PredictionTarget], list[ComparableProperty]]:
    return lambda _target: []


def _epc(property_type: Optional[str]) -> EpcPropertyData:
    epc: EpcPropertyData = object.__new__(EpcPropertyData)
    epc.property_type = property_type
    return epc


def test_unresolved_property_type_raises_with_property_identity() -> None:
    # Arrange — no resolvable property_type (the contradictory/missing-override
    # case): build_prediction_target gates the Property out before any cohort.
    reader = _reader(PredictionTargetAttributes(property_type=None))

    # Act / Assert
    with pytest.raises(UnresolvedPropertyTypeError) as excinfo:
        _predict_epc(
            property_id=733290,
            uprn=100021987320,
            postcode="SE4 1DX",
            portfolio_id=796,
            attributes_reader=reader,
            coordinates=None,
            cohort_for=_no_cohort(),
            broaden=_no_broaden(),
            predictor=EpcPrediction(),
        )

    message = str(excinfo.value)
    assert "733290" in message
    assert "100021987320" in message
    assert "SE4 1DX" in message
    assert "796" in message


def test_resolved_type_but_empty_cohort_raises_no_same_type_comparables() -> None:
    # Arrange — property_type resolves, but neither the own postcode nor the
    # broadened cohort yields a same-type comparable.
    reader = _reader(PredictionTargetAttributes(property_type="2"))

    # Act / Assert
    with pytest.raises(NoSameTypeComparablesError) as excinfo:
        _predict_epc(
            property_id=723681,
            uprn=100021935228,
            postcode="SE13 5RT",
            portfolio_id=796,
            attributes_reader=reader,
            coordinates=None,
            cohort_for=_no_cohort(),
            broaden=_no_broaden(),
            predictor=EpcPrediction(),
        )

    assert excinfo.value.property_type == "2"
    assert excinfo.value.broadened is True
    assert "SE13 5RT" in str(excinfo.value)


def test_cohort_found_but_prediction_has_no_main_part_raises_degenerate() -> None:
    # Arrange — a same-type cohort exists, but the synthesised EPC carries no
    # MAIN building part (the template was lodged with a null part identifier).
    reader = _reader(PredictionTargetAttributes(property_type="2"))
    cohort = [ComparableProperty(epc=_epc("2"), certificate_number="c1")]

    no_main: EpcPropertyData = object.__new__(EpcPropertyData)
    part: SapBuildingPart = object.__new__(SapBuildingPart)
    part.identifier = BuildingPartIdentifier.OTHER
    no_main.sap_building_parts = [part]
    predictor = MagicMock()
    predictor.predict.return_value = no_main

    # Act / Assert
    with pytest.raises(DegeneratePredictionError) as excinfo:
        _predict_epc(
            property_id=712977,
            uprn=100061743824,
            postcode="LS6 1AA",
            portfolio_id=796,
            attributes_reader=reader,
            coordinates=None,
            cohort_for=lambda _postcode: cohort,
            broaden=_no_broaden(),
            predictor=cast(EpcPrediction, predictor),
        )

    assert excinfo.value.cohort_size == 1
    assert "100061743824" in str(excinfo.value)