"""F4 - a run that must be anchored can say so, and is refused before it costs anything.

**The measurement** (``docs/2026-09-07-syretest-s7-prepass-k2.md`` § 8, re-measured here against
the four artefacts the live run left). All three paid arms stamped
``cost_baseline_anchored: False``, so the validator's stage 0 - the ONE stage that tells a
fabricated cost line from a real one - was skipped, and every arm invented its codes:
``ENGRAVE_MARK``, ``RITB-HOURS``/``SYSINT-HOURS``, ``Material_Cost_Concrete``. Stages 2/4/5 judged
those numbers against each other and did their job; nothing tied a single line to K2.

**Option (c) is felled by measurement, not by preference.** The order offers "make
``--derive-cost-baseline`` reachable where it is not today". Measured against the base that ran:
``derive_cost_baseline`` refuses with *no concept file carries a markdown table whose header names
all three of code/quantity/unit_cost* - K2's delivered price schedule is a pandoc SIMPLE table with
ONE column header (``Prisskjema``) and every value collapsed into it. Reaching it would mean
inventing a rule for a form nobody has measured, which is precisely the honesty limit MAJOR-4
wrote down for itself.

**Option (b), and why not (a).** The visibility exists (``cost_baseline_notice``) and is honest;
what it cannot do is stop a machine-readable artefact that says ``validator_decision: validated``
over lines nothing anchored. So: an OPT-IN flag, never a default. Every bundle without a
``cost-baseline.json`` - every commons-owned golden - runs exactly as before, which is what (a)
was protecting; a caller who needs the guarantee asks for it by name.

The gate sits at the ONE place both branches have bound ``baseline`` and BEFORE the dry-run cut, so
it fires on the free trip too (arm (d)) and, on the paid one, before the first model call (arm (a)
asserts NULL calls, never merely the exception - at the exit code a refusal after the spend looks
identical to one before).

Arms: (a) refused, zero model calls * (b) control: without the flag the same base runs *
(c) an anchored base is untouched * (d) the dry run refuses too, with its own control *
(e) it composes with ``--derive-cost-baseline`` * (f)(g)(h) three CLI refusals BY NAME, each with
an rc-0 control on an argv that would otherwise be accepted * (i) the CLI wiring, measured on
calls * (j) the channel.
"""

from __future__ import annotations

import json
import shutil
from pathlib import Path
from typing import Any

import pytest

from portfolio_optimiser import run
from portfolio_optimiser.simulation import ScriptedChatClient

_FIXTURES = Path(__file__).parent / "fixtures"
_PRICED = str(_FIXTURES / "k2-prisskjema-SYNTETISK")
_EXAMPLES = Path(__file__).resolve().parents[1] / "shared" / "examples"
#: A base that SHIPS a hand-written ``cost-baseline.json`` - the anchored control.
_ANCHORED_SOURCE = _EXAMPLES / "tunnel-hauglia"

_IR_PROJECTION = {
    "project_id": "K2",
    "measure": "PLACEHOLDER - authored by this test to satisfy the bundle contract",
    "affected_items": [{"code": "21.1", "quantity": 1250, "unit_cost": 850.0}],
    "claimed_saving_nok": 1000.0,
}


def _runnable(source: str, tmp_path: Path, *, name: str = "runnable") -> str:
    root = tmp_path / name
    shutil.copytree(source, root)
    (root / "validator-input.json").write_text(json.dumps(_IR_PROJECTION), encoding="utf-8")
    return str(root)


def _scripted(sink: list[str] | None = None) -> Any:
    return lambda role: ScriptedChatClient(sink=sink, role=role, default_reply="ok")


# --- (a)/(b)/(c) the library seam -----------------------------------------------------------------


async def test_an_unanchored_run_is_refused_before_it_costs_anything(tmp_path: Path) -> None:
    """(a) The refusal, and the assert that makes it worth having: NULL model calls. Measured on
    calls rather than on the exception, because a refusal placed after the spend raises the same
    exception (session 57's rule, session 82's arm)."""
    bundle_dir = _runnable(_PRICED, tmp_path)
    sink: list[str] = []

    with pytest.raises(run.UnanchoredRunRefused):
        await run.run_project(
            "K2",
            "local",
            docs_dir=bundle_dir,
            bundle_dir=bundle_dir,
            require_cost_baseline=True,
            client_factory=_scripted(sink),
        )

    assert sink == [], f"the run reached the model before it was refused ({len(sink)} calls)"


async def test_control_without_the_flag_the_same_base_runs(tmp_path: Path) -> None:
    """(b) The default is byte-for-byte the path every existing caller takes - which is what
    option (a) of the order was protecting, kept rather than argued away."""
    bundle_dir = _runnable(_PRICED, tmp_path)

    report = await run.run_project(
        "K2", "local", docs_dir=bundle_dir, bundle_dir=bundle_dir, live_dry_run=True
    )

    assert isinstance(report, run.DryRunReport)
    assert report.cost_baseline_anchored is False


async def test_an_anchored_base_is_untouched_by_the_flag(tmp_path: Path) -> None:
    """(c) The gate reads the SAME ``baseline`` the validator is handed, so a base that ships the
    file passes it. Without this arm the flag could be a refusal that always fires."""
    bundle_dir = _runnable(str(_ANCHORED_SOURCE), tmp_path, name="anchored")

    report = await run.run_project(
        "K2",
        "local",
        docs_dir=bundle_dir,
        bundle_dir=bundle_dir,
        require_cost_baseline=True,
        live_dry_run=True,
    )

    assert isinstance(report, run.DryRunReport)
    assert report.cost_baseline_anchored is True


# --- (d) the free trip refuses too ----------------------------------------------------------------


async def test_the_dry_run_refuses_rather_than_reporting_an_unanchored_run(tmp_path: Path) -> None:
    """(d) The gate is ABOVE the dry-run cut on purpose: the dry run's whole job is to say what a
    real run would do, and it is the cheapest place to learn that this one may not run at all."""
    bundle_dir = _runnable(_PRICED, tmp_path)

    with pytest.raises(run.UnanchoredRunRefused):
        await run.run_project(
            "K2",
            "local",
            docs_dir=bundle_dir,
            bundle_dir=bundle_dir,
            require_cost_baseline=True,
            live_dry_run=True,
        )


# --- (e) it composes with the derivation ----------------------------------------------------------


async def test_it_composes_with_the_derivation(tmp_path: Path) -> None:
    """(e) ``--derive-cost-baseline`` is the OTHER half of the answer: derive, and the requirement
    is met. Two flags that could not be combined would leave the guarantee unreachable on exactly
    the bases MAJOR-4 was built for."""
    bundle_dir = _runnable(_PRICED, tmp_path)

    report = await run.run_project(
        "K2",
        "local",
        docs_dir=bundle_dir,
        bundle_dir=bundle_dir,
        derive_cost_baseline=True,
        require_cost_baseline=True,
        live_dry_run=True,
    )

    assert isinstance(report, run.DryRunReport)
    assert report.cost_baseline_anchored is True


# --- (f)/(g)/(h) three CLI refusals, each with an rc-0 control -------------------------------------


def test_cli_requires_bundle_dir(capsys: pytest.CaptureFixture[str]) -> None:
    """(f) The road path is anchored by construction, so on it the flag could never fire. A flag
    that cannot fire is a claim the surface makes about itself (the Fase-3 class)."""
    rc = run.main(["P1", "--docs-dir", "docs", "--require-cost-baseline"])

    assert rc == 1
    assert "--require-cost-baseline" in capsys.readouterr().err


def test_cli_is_refused_in_portfolio_mode(capsys: pytest.CaptureFixture[str]) -> None:
    """(g) BY NAME, never by falling through to the ``--bundle-dir`` requirement: that message
    would tell an operator who wrote ``--portfolio --require-cost-baseline`` to add the one flag
    this mode also refuses (the ``--derive-cost-baseline`` precedent, and session 57's)."""
    rc = run.main(["--portfolio", "--require-cost-baseline"])

    assert rc == 1
    err = capsys.readouterr().err
    assert "--portfolio" in err, "the refusal never names the mode that refused it"


def test_cli_is_refused_in_report_mode(tmp_path: Path, capsys: pytest.CaptureFixture[str]) -> None:
    """(h) Report mode returns ABOVE every run dispatch, so an omission from this allowlist is a
    SILENT DROP rather than a refusal - the gap F4 itself measured on ``--plan-review``."""
    ledger = tmp_path / "ledger.json"
    ledger.write_text("[]", encoding="utf-8")

    assert run.main(["--report", "--ledger", str(ledger)]) == 0, "the control argv must be ACCEPTED"
    capsys.readouterr()

    rc = run.main(["--report", "--ledger", str(ledger), "--require-cost-baseline"])

    assert rc == 1
    # The allowlist's own wording, not the flag name: this partition refuses generically, and the
    # discriminator is the rc-0 control above -- the same argv without the flag is ACCEPTED.
    assert "mode-exclusive" in capsys.readouterr().err


# --- (i) the CLI wiring ---------------------------------------------------------------------------


def test_cli_wiring_refuses_the_unanchored_run_without_paying(
    tmp_path: Path, monkeypatch: pytest.MonkeyPatch, capsys: pytest.CaptureFixture[str]
) -> None:
    """(i) The flag must REACH ``run_project``. rc 1 alone would also be a parse error, so the
    discriminator is that no model call happened - and the control proves the same argv without
    the flag is accepted and DOES call."""
    monkeypatch.delenv("PORTFOLIO_MODEL_MAP", raising=False)
    bundle_dir = _runnable(_PRICED, tmp_path)
    sink: list[str] = []
    monkeypatch.setattr("portfolio_optimiser.run._default_factory", lambda profile: _scripted(sink))

    argv = ["K2", "--docs-dir", bundle_dir, "--bundle-dir", bundle_dir]
    assert run.main([*argv, "--live-dry-run"]) == 0, "the control argv must be ACCEPTED"

    rc = run.main([*argv, "--require-cost-baseline"])

    assert rc == 1
    assert sink == [], f"the run was refused only after paying for it ({len(sink)} calls)"
    assert "run refused" in capsys.readouterr().err


# --- (j) the channel ------------------------------------------------------------------------------


def test_the_refusal_lands_on_the_refusal_tuple() -> None:
    """(j) A ``ValueError``, the ``BundleIdMismatch``/``CostBaselineDerivationError`` precedent: an
    argv that is wrong about what this base can offer belongs on the CLI's refusal tuple, never on
    the crash channel."""
    assert issubclass(run.UnanchoredRunRefused, ValueError)