"""
Unit tests for HybridRAG degradation signaling (offline, all clients mocked).

Covers:
- Per-leg failure -> source_status reports 'failed', degraded=True
- Disabled legs -> 'disabled', do not trigger degraded
- Healthy legs -> 'ok', degraded=False
- Reranker model resolution from settings.ollama_llm_model
- Phase 0 keyword-extraction timeout falls back gracefully
"""

import asyncio
from unittest.mock import AsyncMock, MagicMock

import pytest

import src.services.hybrid_rag_service as hybrid_rag_module
from src.services.hybrid_rag_service import HybridRAGService
from src.models.hybrid_rag import HybridRAGConfig


@pytest.fixture
def settings():
    settings = MagicMock()
    settings.ollama_llm_model = "gemma4:e2b"
    settings.vector_similarity_threshold = 0.7
    return settings


@pytest.fixture
def vector_service():
    """Vector service returning a single wiki hit."""
    vector = MagicMock()
    hit = MagicMock()
    hit.page_id = 1
    hit.page_title = "Test Page"
    hit.content = "Test content"
    hit.page_path = "users/jp/test"
    hit.score = 0.9
    response = MagicMock()
    response.results = [hit]
    vector.search = AsyncMock(return_value=response)
    return vector


@pytest.fixture
def graph_service():
    graph = MagicMock()
    graph.search_documents = AsyncMock(return_value=[])
    graph.get_related_documents = AsyncMock(return_value=[])
    graph.neo4j.execute_query = AsyncMock(return_value=[{"id": "search-1"}])
    return graph


@pytest.fixture
def searxng_client():
    searxng = MagicMock()
    searxng.search_general = AsyncMock(return_value=[])
    return searxng


@pytest.fixture
def ollama_client():
    ollama = MagicMock()
    ollama.generate_text = AsyncMock(
        return_value='{"core_keywords": ["test"], "synonyms": {}}'
    )
    return ollama


@pytest.fixture
def content_extractor():
    extractor = MagicMock()
    extractor.extract_batch = AsyncMock(return_value=[])
    return extractor


@pytest.fixture
def service(settings, vector_service, graph_service, searxng_client, ollama_client, content_extractor):
    return HybridRAGService(
        vector_service=vector_service,
        graph_service=graph_service,
        searxng_client=searxng_client,
        ollama_client=ollama_client,
        content_extractor=content_extractor,
        settings=settings,
        volatile_service=None,
    )


def make_config(**overrides):
    """Config with documents disabled (leg needs a real Qdrant client) and fast phases."""
    defaults = {
        "enable_documents": False,
        "enable_volatile": False,
        "enable_reranking": False,
        "enable_enrichment": False,
    }
    defaults.update(overrides)
    return HybridRAGConfig(**defaults)


@pytest.mark.unit
class TestSourceStatus:
    """source_status must report every leg as ok/failed/disabled."""

    async def test_all_enabled_legs_ok(self, service):
        response = await service.search("test query", "jp", make_config())

        assert response.source_status == {
            "vector": "ok",
            "graph": "ok",
            "web": "ok",
            "volatile": "disabled",
            "documents": "disabled",
        }
        assert response.degraded is False

    async def test_failed_leg_reported_and_degraded(self, service, graph_service):
        graph_service.search_documents = AsyncMock(side_effect=RuntimeError("neo4j down"))

        response = await service.search("test query", "jp", make_config())

        assert response.source_status["graph"] == "failed"
        assert response.source_status["vector"] == "ok"
        assert response.degraded is True

    async def test_failed_leg_still_contributes_no_results(self, service, graph_service):
        """Existing behavior preserved: failure -> empty leg, other legs still work."""
        graph_service.search_documents = AsyncMock(side_effect=RuntimeError("neo4j down"))

        response = await service.search("test query", "jp", make_config())

        # The vector hit still comes through
        assert response.total_results == 1
        assert response.results[0].page_id == 1

    async def test_multiple_failures(self, service, graph_service, searxng_client):
        graph_service.search_documents = AsyncMock(side_effect=RuntimeError("neo4j down"))
        searxng_client.search_general = AsyncMock(side_effect=OSError("searxng unreachable"))

        response = await service.search("test query", "jp", make_config())

        assert response.source_status["graph"] == "failed"
        assert response.source_status["web"] == "failed"
        assert response.degraded is True

    async def test_disabled_legs_do_not_degrade(self, service):
        config = make_config(enable_graph=False, enable_web=False)

        response = await service.search("test query", "jp", config)

        assert response.source_status["graph"] == "disabled"
        assert response.source_status["web"] == "disabled"
        assert response.degraded is False

    async def test_volatile_without_service_is_disabled(self, service):
        """enable_volatile=True but no volatile service wired -> disabled, not failed."""
        response = await service.search("test query", "jp", make_config(enable_volatile=True))

        assert response.source_status["volatile"] == "disabled"
        assert response.degraded is False

    async def test_status_fields_serialized(self, service, graph_service):
        """Contract: fields present in the serialized response for tatlock to parse."""
        graph_service.search_documents = AsyncMock(side_effect=RuntimeError("boom"))

        response = await service.search("test query", "jp", make_config())
        payload = response.model_dump()

        assert set(payload["source_status"].keys()) == {"vector", "graph", "web", "volatile", "documents"}
        assert payload["degraded"] is True


@pytest.mark.unit
class TestModelResolution:
    """The reranker/keyword model must come from settings.ollama_llm_model."""

    def test_reranker_model_from_llm_setting(self, service):
        assert service.reranker_model == "gemma4:e2b"

    async def test_generation_calls_use_llm_model(self, service, ollama_client):
        await service.search("test query", "jp", make_config())

        # Phase 0 keyword extraction ran with the generation model
        assert ollama_client.generate_text.await_count >= 1
        for call in ollama_client.generate_text.await_args_list:
            assert call.kwargs["model"] == "gemma4:e2b"


@pytest.mark.unit
class TestLLMTimeout:
    """A hung LLM call must not gate retrieval: 12s wait_for with fallback."""

    async def test_keyword_extraction_timeout_falls_back(self, service, ollama_client, monkeypatch):
        monkeypatch.setattr(hybrid_rag_module, "LLM_CALL_TIMEOUT_SECONDS", 0.05)

        async def hang(*args, **kwargs):
            await asyncio.sleep(5)

        ollama_client.generate_text = AsyncMock(side_effect=hang)

        response = await service.search("test query", "jp", make_config())

        # Fallback: raw query words as keywords, retrieval still ran
        assert response.keywords.core_keywords == ["test", "query"]
        assert response.source_status["vector"] == "ok"

    async def test_rerank_timeout_keeps_rrf_order(self, service, ollama_client, monkeypatch, searxng_client, content_extractor):
        monkeypatch.setattr(hybrid_rag_module, "LLM_CALL_TIMEOUT_SECONDS", 0.05)

        # Two web results so re-ranking actually runs (needs > 1 result)
        searxng_client.search_general = AsyncMock(return_value=[
            {"url": "http://a.test", "title": "A", "content": "a"},
            {"url": "http://b.test", "title": "B", "content": "b"},
        ])

        keyword_json = '{"core_keywords": ["test"], "synonyms": {}}'

        async def generate(prompt, **kwargs):
            if "Rank these documents" in prompt:
                await asyncio.sleep(5)  # Hang only the re-rank call
            return keyword_json

        ollama_client.generate_text = AsyncMock(side_effect=generate)

        response = await service.search("test query", "jp", make_config(enable_reranking=True))

        # RRF order preserved despite the hung re-rank call
        assert response.total_results >= 2
        assert response.degraded is False