"""Entry point: INV-5, offline before torch/transformers load. Contract: intern-decision-serve.contract.md."""
import os

from fake_engine import FakeEngine


def test_app_from_env_goes_offline_before_the_engine_loads(monkeypatch):
    from intern_decision_serve import engine as engine_module
    from intern_decision_serve import main
    seen = {}

    def fake_load(settings, **_kw):
        seen["offline"] = (os.environ.get("HF_HUB_OFFLINE"), os.environ.get("TRANSFORMERS_OFFLINE"))
        seen["token"] = settings.api_token
        return FakeEngine()

    monkeypatch.delenv("HF_HUB_OFFLINE", raising=False)
    monkeypatch.delenv("TRANSFORMERS_OFFLINE", raising=False)
    monkeypatch.setenv("INTERN_DECISION_API_TOKEN", "k" * 40)
    monkeypatch.setattr(engine_module.TorchEngine, "load", staticmethod(fake_load))
    app = main.app_from_env()
    assert seen == {"offline": ("1", "1"), "token": "k" * 40}
    assert app.title == "intern-decision-serve"


def test_the_engine_loads_on_the_same_thread_every_call_later_runs_on(monkeypatch):
    import threading
    from intern_decision_serve import engine as engine_module
    from intern_decision_serve import main
    from fastapi.testclient import TestClient
    seen = {}

    class Recording(FakeEngine):
        def predict(self, request):
            seen.setdefault("calls", set()).add(threading.get_ident())
            return super().predict(request)

    def fake_load(settings, **_kw):
        seen["load"] = threading.get_ident()
        return Recording()

    monkeypatch.setenv("INTERN_DECISION_API_TOKEN", "k" * 40)
    monkeypatch.setattr(engine_module.TorchEngine, "load", staticmethod(fake_load))
    client = TestClient(main.app_from_env())
    body = {"id": "r", "state": "s", "question": "q?", "options": [{"id": "a", "description": "A"},
                                                                  {"id": "b", "description": "B"}]}
    assert client.post("/decide", json=body, headers={"Authorization": "Bearer " + "k" * 40}).status_code == 200
    assert seen["calls"] == {seen["load"]} and seen["load"] != threading.get_ident()