"""SDK build in the provenance stamp — LOAD-BEARING (§1, §9, §11).

The seam this file keeps alive: a run's provenance records **which SDK build
produced it**, and it takes that from the PRODUCING CLIENT, never from the
environment. That distinction is the whole point. The SDK's reported
``total_cost_usd`` is a client-side estimate computed against a price table
frozen when the SDK was built, so a cost figure is only traceable if the run
says which build produced it. But a run driven by the scripted stand-in used no
SDK at all — stamping the installed version there would attribute a build to a
run that never touched it, which is exactly the fabrication §1 forbids.

Detach proof: make the stamp read ``importlib.metadata`` instead of the client
→ a scripted run claims an SDK build it never used → red.

Second guard: the S10 fasit predates this field and is a historical record of a
run executed 2026-07-03. Retro-stamping it would invent provenance for a run
whose SDK build we would be guessing. The fasit stays byte-frozen — red the
moment someone back-fills it.
"""

from __future__ import annotations

import importlib.metadata
import json
from pathlib import Path
from typing import Callable

import pytest
from pydantic import ValidationError

from _scripted import ScriptedClient, reply

from portfolio_optimiser_claude.contracts import Contracts, ModelMapContract
from portfolio_optimiser_claude.ir import load_validator_input
from portfolio_optimiser_claude.loop import ModelClient
from portfolio_optimiser_claude.provenance import Citation, Provenance
from portfolio_optimiser_claude.run import main
from portfolio_optimiser_claude.sdk_client import SdkModelClient

REPO_ROOT = Path(__file__).resolve().parents[1]
BUNDLE = REPO_ROOT / "shared" / "examples" / "bygg-energi-mikro"
S10_PROVENANCE = REPO_ROOT / "runs" / "s10" / "provenance.json"

ClientFactory = Callable[[Contracts, float], ModelClient]

# A build id no installed package could ever report, so a test that sees it
# knows the value came from the CLIENT and from nowhere else.
FIXTURE_BUILD = "0.2.120-fixture-not-installed"


def _scripted_factory(*, sdk_version: str | None) -> tuple[ClientFactory, list[ScriptedClient]]:
    created: list[ScriptedClient] = []

    def factory(contracts: Contracts, max_budget_usd_per_call: float) -> ModelClient:
        client = ScriptedClient(
            replies=[
                reply("debate reasoning"),
                reply("VERDICT: APPROVE"),
                reply(json.dumps(load_validator_input(BUNDLE).model_dump())),
            ]
        )
        if sdk_version is not None:
            # Only a client that genuinely carries the attribute reports one.
            client.sdk_version = sdk_version  # type: ignore[attr-defined]
        created.append(client)
        return client

    return factory, created


def _run_and_read_provenance(tmp_path: Path, *, sdk_version: str | None) -> dict[str, object]:
    out = tmp_path / "out"
    factory, _ = _scripted_factory(sdk_version=sdk_version)
    code = main(["--bundle", str(BUNDLE), "--out", str(out)], client_factory=factory)
    assert code == 0
    payload: dict[str, object] = json.loads((out / "provenance.json").read_text(encoding="utf-8"))
    return payload


class TestTheStampComesFromTheClient:
    """LOAD-BEARING (§11): the producing client reports the build, or nobody does."""

    def test_a_run_not_produced_by_the_sdk_stamps_no_build(self, tmp_path: Path) -> None:
        # Detach point: read importlib.metadata instead of the client → this
        # scripted run claims the installed build it never used → RED.
        payload = _run_and_read_provenance(tmp_path, sdk_version=None)
        assert payload["sdk_version"] is None
        assert payload["sdk_version"] != importlib.metadata.version("claude-agent-sdk")

    def test_a_producing_client_has_its_build_stamped_verbatim(self, tmp_path: Path) -> None:
        payload = _run_and_read_provenance(tmp_path, sdk_version=FIXTURE_BUILD)
        assert payload["sdk_version"] == FIXTURE_BUILD

    def test_the_sdk_client_reports_the_installed_build_offline(self) -> None:
        # Constructing the real client needs no key and touches no network
        # (the same premise test_sdk_isolation.py relies on), so the build id
        # it exposes is readable in the offline suite.
        client = SdkModelClient(
            ModelMapContract(profiles={"anthropic": {"default": "claude-haiku-4-5-20251001"}})
        )
        assert client.sdk_version == importlib.metadata.version("claude-agent-sdk")


class TestTheStampStaysOptional:
    """The field is additive: every existing caller keeps validating unchanged."""

    def test_provenance_validates_without_a_build(self) -> None:
        stamp = Provenance(
            citations=[Citation(file="index.md", span="chars 0-1", snippet="x")],
            model="claude-haiku-4-5-20251001",
            role="proposer",
            validator_decision="validated",
            tokens_used=10,
        )
        assert stamp.sdk_version is None

    def test_a_blank_build_is_refused_rather_than_stored(self) -> None:
        # An empty string would read as "no SDK" while occupying the field —
        # null is the one way to say "not produced by the SDK" (§1).
        with pytest.raises(ValidationError):
            Provenance(
                citations=[Citation(file="index.md", span="chars 0-1", snippet="x")],
                model="m",
                role="proposer",
                validator_decision="validated",
                tokens_used=10,
                sdk_version="",
            )


class TestTheFasitIsNotRetroStamped:
    """LOAD-BEARING (§1): the historical record is never back-filled."""

    def test_the_s10_provenance_carries_no_sdk_build(self) -> None:
        # runs/s10/ is the byte-frozen record of the ONE live run (2026-07-03),
        # executed before this field existed. Adding a build id to it now would
        # be a guess presented as provenance. RED if someone back-fills it.
        payload = json.loads(S10_PROVENANCE.read_text(encoding="utf-8"))
        assert "sdk_version" not in payload
        assert payload["model"] == "claude-haiku-4-5-20251001"