"""Fault-tolerance coverage for Deep Research progress events."""

import pytest

from deerflow.agents.deep_research.adapters.event_sink import PersistingEventSink


class _UnavailableEventRepository:
    async def append(self, **kwargs):  # noqa: ANN003
        raise RuntimeError("database temporarily unavailable")


@pytest.mark.asyncio
async def test_event_persistence_failure_keeps_job_live_and_emits_unique_fallback_event():
    published: list[dict] = []

    async def publish(event: dict) -> None:
        published.append(event)

    sink = PersistingEventSink(
        _UnavailableEventRepository(),
        session_id="drs_1",
        job_id="drj_1",
        on_event=publish,
    )

    first = await sink.emit("phase_changed", phase="planning", payload={"to": "planning"})
    second = await sink.emit("queries_planned", phase="collecting", payload={"queries": ["AI"]})

    assert (first.seq, second.seq) == (-1, -2)
    assert first.payload["eventPersistenceDegraded"] is True
    assert published[0]["liveId"] == "event-persistence-fallback:drj_1:1"
    assert published[1]["liveId"] == "event-persistence-fallback:drj_1:2"


@pytest.mark.asyncio
async def test_live_publish_failure_does_not_fail_event_delivery():
    class _EventRepository:
        async def append(self, **kwargs):  # noqa: ANN003
            return {
                "seq": 1,
                "event_type": kwargs["event_type"],
                "phase": kwargs["phase"],
                "payload": kwargs["payload"],
            }

    async def broken_publisher(event: dict) -> None:  # noqa: ARG001
        raise RuntimeError("browser disconnected")

    sink = PersistingEventSink(
        _EventRepository(),
        session_id="drs_1",
        job_id="drj_1",
        on_event=broken_publisher,
    )

    event = await sink.emit("phase_changed", phase="planning")

    assert event.seq == 1


@pytest.mark.asyncio
async def test_document_rewrite_milestone_is_a_supported_durable_event():
    """Guard the artifact-rewrite job path against EventType regressions."""

    class _EventRepository:
        async def append(self, **kwargs):  # noqa: ANN003
            return {
                "seq": 1,
                "event_type": kwargs["event_type"],
                "phase": kwargs["phase"],
                "payload": kwargs["payload"],
            }

    sink = PersistingEventSink(_EventRepository(), session_id="drs_1", job_id="drj_1")

    event = await sink.emit(
        "document_rewrite",
        phase="planning",
        payload={"type": "requirements_started"},
    )

    assert event.type == "document_rewrite"