"""Step 2 tests — the promoted blocking validator + IR (B1). Crafted IR, deterministic.

Determinism is asserted over FIXED inputs (seed 20260624), never through an LLM. The
out-of-range path returns a ``Rejection`` that carries no percentiles, so it can never be
consumed as validated. Pattern: tests/spikes/test_c_validator.py.
"""

import pytest
from pydantic import ValidationError

from portfolio_optimiser.ir import SavingsProposal
from portfolio_optimiser.reference_domain import load_reference_projects
from portfolio_optimiser.validator import (
    Rejection,
    ValidatedProposal,
    proposal_for,
    validate_proposal,
)

_ASSUMPTIONS = {"05.2": (200.0, 230.0), "03.1": (290.0, 330.0)}


@pytest.fixture(scope="module")
def project():
    return load_reference_projects()[0]  # FV42-GSV-E1


def _valid(project) -> SavingsProposal:
    # Affected total ~1.48M NOK; 30% feasible cap ~0.44M. Claim 200k is comfortably feasible.
    return proposal_for(
        project, ["05.2", "03.1"], claimed_saving_nok=200_000, assumptions=_ASSUMPTIONS
    )


def _out_of_range(project) -> SavingsProposal:
    # Constructs fine (800k <= 1.48M total) but far exceeds the ~0.44M feasible cap.
    return proposal_for(
        project, ["05.2", "03.1"], claimed_saving_nok=800_000, assumptions=_ASSUMPTIONS
    )


def test_valid_proposal_yields_ordered_percentiles(project) -> None:
    result = validate_proposal(_valid(project))
    assert isinstance(result, ValidatedProposal)
    assert result.p10 <= result.p50 <= result.p90  # P10 <= P50 <= P90
    assert result.nominal_feasible > 0  # the CBC solve produced a feasible bound


def test_out_of_range_is_structurally_blocked(project) -> None:
    result = validate_proposal(_out_of_range(project))
    assert isinstance(result, Rejection)
    assert result.reason  # carries a human-readable reason
    # A Rejection carries no percentiles -> it can never be consumed as validated.
    with pytest.raises(AttributeError):
        _ = result.p50  # type: ignore[attr-defined]


def test_monte_carlo_is_reproducible(project) -> None:
    a = validate_proposal(_valid(project))
    b = validate_proposal(_valid(project))
    assert isinstance(a, ValidatedProposal) and isinstance(b, ValidatedProposal)
    assert (a.p10, a.p50, a.p90) == (b.p10, b.p50, b.p90)


def test_pydantic_blocks_negative_quantity() -> None:
    with pytest.raises(ValidationError):
        SavingsProposal(
            project_id="X",
            measure="bad",
            affected_items=[{"code": "A", "quantity": -1, "unit_cost": 10}],
            claimed_saving_nok=1,
        )


def test_pydantic_blocks_claim_above_affected_total(project) -> None:
    with pytest.raises(ValidationError):
        proposal_for(project, ["05.2"], claimed_saving_nok=99_000_000)