portfolio-optimiser/tests/test_ledger_loadbearing.py

"""Load-bearing seams for the savings ledger (Fase 1 — SC4/SC5/SC6/SC8).

Step 5 (SC4) — the dimension-free dedup gate: the same underlying candidate (same codes+measure+
amount) realized under two dimensions counts ONCE in the portfolio sum — double-counting across
dimensions is the exact error SC4 warns against — while the overlap is FLAGGED (never silently
merged). RED if the dimension-free sum-key dedup is detached (the sum doubles). Inverse control:
two DISTINCT realizations with the same codes+measure but a different amount stay SEPARATE (a
magnitude-free identity would collide them).

(Step 6 extends this file with the fail-closed ``realize`` gate + øre-boundary tests; Step 8 adds
the goal-stop detach.)

Pattern: ``tests/test_step8_promotion_loadbearing.py:77`` (fail-closed gate trio).
"""

from __future__ import annotations

import pytest

from portfolio_optimiser.ledger import (
    LedgerEntry,
    RealizationRefused,
    SavingsLedger,
    _candidate_identity,
    realize,
    stamp,
)
from portfolio_optimiser.verdicts import ProposalFeatures, Verdict

_TS = "2026-07-06T00:00:00Z"
_CODES = frozenset({"ENERGI-TOTAL-EL"})
_MEASURE = "energy_efficiency"


def _identity(amount_ore: int) -> str:
    return _candidate_identity(affected_codes=_CODES, measure_type=_MEASURE, amount_ore=amount_ore)


def _entry(dimension: str, *, amount_ore: int) -> LedgerEntry:
    return LedgerEntry(
        project_id="P1",
        dimension=dimension,
        candidate_identity=_identity(amount_ore),
        amount_ore=amount_ore,
        verdict_id="v1",
        provenance=stamp(approver="ekspert", experiment="sim", timestamp=_TS),
    )


def test_same_candidate_two_dimensions_counts_once_and_flags_overlap() -> None:
    """LOAD-BEARING (SC4): the same underlying candidate realized under two dimensions contributes
    ONCE to the portfolio sum, and the overlap is flagged. RED if the dimension-free sum-key dedup
    is detached in ``_dedup_amount`` (the sum then doubles to 10000)."""
    ledger = SavingsLedger()
    assert ledger.add_realized(_entry("energi", amount_ore=5000)) is True
    # Same candidate identity (same codes+measure+amount), a DIFFERENT dimension -> distinct full
    # key -> stored, so the overlap is visible; the sum must still count it once.
    assert ledger.add_realized(_entry("asfalt", amount_ore=5000)) is True

    assert ledger.portfolio_total() == 5000, (
        "double-counted the same candidate across dimensions (SC4)"
    )
    assert ledger.per_project_total("P1") == 5000
    assert ledger.overlaps() == [("P1", _identity(5000))]


def test_distinct_amounts_same_codes_measure_are_not_collided() -> None:
    """INVERSE CONTROL (fixes the magnitude-free collision): two DISTINCT realizations with the same
    codes+measure but a different amount are separate candidates -> both counted, no overlap."""
    ledger = SavingsLedger()
    assert ledger.add_realized(_entry("energi", amount_ore=5000)) is True
    assert ledger.add_realized(_entry("energi", amount_ore=7000)) is True  # distinct identity

    assert ledger.portfolio_total() == 12000  # both counted (no collision)
    assert ledger.overlaps() == []  # single dimension -> no cross-dimension overlap


def test_exact_full_key_duplicate_is_not_stored_twice() -> None:
    """An exact (project, dimension, candidate) re-add is a no-op — storage keys on the full key."""
    ledger = SavingsLedger()
    assert ledger.add_realized(_entry("energi", amount_ore=5000)) is True
    assert ledger.add_realized(_entry("energi", amount_ore=5000)) is False  # exact duplicate
    assert ledger.portfolio_total() == 5000


# --- Step 6: fail-closed realize gate + deterministic øre conversion (SC5/SC8) --------------------


def _features(nok: float = 5000.0) -> ProposalFeatures:
    return ProposalFeatures(affected_codes=_CODES, measure_type=_MEASURE, claimed_saving_nok=nok)


def _verdict(decision: str) -> Verdict:
    return Verdict(
        id="v-abc", proposal_features=_features(), decision=decision, rationale="expert prose"
    )


def test_realize_fail_closed_refuses_non_approved() -> None:
    """LOAD-BEARING (SC5): a non-approved verdict — OTHERWISE fully valid (correct amount, valid
    provenance, so detaching the gate WOULD add it) — raises ``RealizationRefused`` and the ledger is
    unchanged. RED the moment the ``raise`` detaches: the raw entry then appears (self-contamination)."""
    ledger = SavingsLedger()
    with pytest.raises(RealizationRefused):
        realize(
            ledger,
            _features(),
            _verdict("rejected"),
            project_id="P1",
            dimension="energi",
            approver="ekspert",
            experiment="sim",
            timestamp=_TS,
        )
    assert ledger.entries == []  # nothing written
    assert ledger.portfolio_total() == 0


def test_realize_approved_reaches_ledger() -> None:
    """CAUSALITY: a HITL-approved verdict reaches the ledger (5000 NOK -> 500000 øre)."""
    ledger = SavingsLedger()
    entry = realize(
        ledger,
        _features(),
        _verdict("approved"),
        project_id="P1",
        dimension="energi",
        approver="ekspert",
        experiment="sim",
        timestamp=_TS,
    )
    assert entry in ledger.entries
    assert entry.verdict_id == "v-abc"
    assert ledger.portfolio_total() == 500000


def test_realize_accepts_approved_with_adjustment() -> None:
    """The gate uses the PROMOTION set: ``approved_with_adjustment`` is admitted (not the binary
    run-path FeedbackContract — H6)."""
    ledger = SavingsLedger()
    realize(
        ledger,
        _features(),
        _verdict("approved_with_adjustment"),
        project_id="P1",
        dimension="energi",
        approver="ekspert",
        experiment="sim",
        timestamp=_TS,
    )
    assert ledger.portfolio_total() == 500000


def test_realize_requires_timestamp_keyword() -> None:
    """SC8: ``timestamp`` is a required keyword — no wall-clock default. Omitting it raises TypeError."""
    ledger = SavingsLedger()
    with pytest.raises(TypeError):
        realize(
            ledger,
            _features(),
            _verdict("approved"),
            project_id="P1",
            dimension="energi",
            approver="ekspert",
            experiment="sim",
        )  # no timestamp


def test_realize_ore_conversion_is_exact() -> None:
    """øre boundary: 12345.67 NOK -> 1234567 øre exactly, no binary-float ...66.9999 drift."""
    ledger = SavingsLedger()
    entry = realize(
        ledger,
        _features(12345.67),
        _verdict("approved"),
        project_id="P1",
        dimension="energi",
        approver="ekspert",
        experiment="sim",
        timestamp=_TS,
    )
    assert entry.amount_ore == 1234567