"""Engine-Kern: atomarer Claim, Zombie-Reset, Idempotenz, Kanten-Validierung."""
import pytest

from backend import db, engine, graph
from .conftest import topic_anlegen


def test_claim_atomar():
    topic = topic_anlegen()
    run_id = db.insert("runs", topic=topic, status="running")
    tid = db.insert("tasks", run_id=run_id, topic=topic, knoten="suche", item="x")
    assert db.execute("UPDATE tasks SET status='laufend' WHERE id=? AND "
                      "status='offen'", tid) == 1
    # zweiter Claim verliert
    assert db.execute("UPDATE tasks SET status='laufend' WHERE id=? AND "
                      "status='offen'", tid) == 0


def test_task_unique_idempotent():
    topic = topic_anlegen()
    run_id = db.insert("runs", topic=topic, status="running")
    a = db.insert("tasks", ignore=True, run_id=run_id, topic=topic,
                  knoten="suche", item="r1:q:abc")
    b = db.insert("tasks", ignore=True, run_id=run_id, topic=topic,
                  knoten="suche", item="r1:q:abc")
    assert a is not None and b is None
    # Runde im Item-Schlüssel: 2. Runde blockiert nicht
    c = db.insert("tasks", ignore=True, run_id=run_id, topic=topic,
                  knoten="suche", item="r2:q:abc")
    assert c is not None


async def test_zombie_reset_beim_start():
    import asyncio
    topic = topic_anlegen()
    run_id = db.insert("runs", topic=topic, status="stopped")
    db.insert("tasks", run_id=run_id, topic=topic, knoten="montage",
              item="montage", status="laufend")
    run_id2 = engine.lauf_starten(topic)
    await asyncio.sleep(0.1)
    t = db.one("SELECT status, fehler FROM tasks WHERE topic=? AND item='montage'",
               topic)
    assert t["status"] != "laufend" or t["fehler"] != ""  # Zombie zurückgesetzt
    engine.lauf_stoppen(topic)
    with __import__("contextlib").suppress(asyncio.CancelledError):
        await engine._laeufe[topic]
    assert run_id2 != run_id


def test_kanten_validierung():
    g = graph.get()
    kn = g.knoten["suche"]
    t = {"id": 1, "run_id": 1, "topic": "x", "knoten": "suche", "item": "i",
         "runde": 1}
    erg = engine.Ergebnis(neue_tasks=[{"knoten": "montage", "item": "m"}])
    with pytest.raises(graph.GraphFehler):
        engine._abschluss_schreiben(g, t, kn, erg)


async def test_infra_zaehlt_nicht_gegen_versuch():
    """LaufPause aus einem Worker setzt den Task zurück auf offen (kein versuch+1)
    und pausiert den Run."""
    import asyncio

    async def kaputt(task):
        from backend.llm import LaufPause
        raise LaufPause("test")

    topic = topic_anlegen()
    run_id = db.insert("runs", topic=topic, status="running")
    tid = db.insert("tasks", run_id=run_id, topic=topic, knoten="suche",
                    item="x", status="laufend", versuch=0)
    g = graph.get()
    alt = engine.WORKER["suche.suchen"]
    engine.WORKER["suche.suchen"] = kaputt
    try:
        t = dict(db.one("SELECT * FROM tasks WHERE id=?", tid))
        await engine._ausfuehren(g, t, g.knoten["suche"], asyncio.Semaphore(1),
                                 asyncio.Semaphore(1), asyncio.Event())
    finally:
        engine.WORKER["suche.suchen"] = alt
    task = db.one("SELECT * FROM tasks WHERE id=?", tid)
    assert task["status"] == "offen"
    assert task["versuch"] == 0  # Infra zählt nicht als Inhalts-Versuch
    assert db.one("SELECT status FROM runs WHERE id=?", run_id)["status"] == "paused"