import pytest

from app.core.contracts import RequestContext
from app.core.errors import RecoverableAgentError
from app.core.knowledge_contracts import KnowledgeHit, KnowledgeQuery
from app.service.knowledge_config import KnowledgeRuntimeConfig
from app.service.knowledge_retrieval_service import KnowledgeRetrievalService

# ruff: noqa: E501


class FakeEmbedder:
    async def embed(self, text: str) -> list[float]:
        assert text == "开户"
        return [0.1] * 1024


class FakeVectorStore:
    def __init__(self) -> None:
        self.calls: list[tuple[str, int]] = []

    async def search(self, collection: str, vector: list[float], top_k: int) -> list[dict[str, object]]:
        assert len(vector) == 1024
        self.calls.append((collection, top_k))
        return []


class FakeAuthority:
    async def filter_published(self, hits: tuple[object, ...]) -> list[object]:
        return []

    async def search_keyword(self, query: object, collections: tuple[str, ...], top_k: int) -> list[object]:
        return []


class BrokenVectorStore:
    async def search(self, collection: str, vector: list[float], top_k: int) -> list[dict[str, object]]:
        raise RecoverableAgentError("知识检索不可用")


class FallbackAuthority:
    def __init__(self) -> None:
        self.calls: list[tuple[tuple[str, ...], int]] = []

    async def filter_published(self, hits: tuple[object, ...]) -> list[object]:
        return []

    async def search_keyword(self, query: KnowledgeQuery, collections: tuple[str, ...], top_k: int) -> list[KnowledgeHit]:
        self.calls.append((collections, top_k))
        return [KnowledgeHit(
            knowledge_id="101", collection="fin_policy_collection", snippet="确认规则",
            answer="工作日确认", score=1.0,
        )]


@pytest.mark.asyncio
async def test_search_uses_faq_collection_for_faq_only() -> None:
    vector_store = FakeVectorStore()
    service = KnowledgeRetrievalService(
        FakeEmbedder(), vector_store, KnowledgeRuntimeConfig(), FakeAuthority()
    )

    result = await service.search(
        KnowledgeQuery(query="开户", intents=("faq",)),
        RequestContext(user_id="visitor-1", trace_id="trace", roles=("visitor",), data_scope="public"),
    )

    assert vector_store.calls == [("fin_faq_collection", 3)]
    assert result.searched_collections == ("fin_faq_collection",)


@pytest.mark.asyncio
async def test_milvus_failure_falls_back_to_published_active_unexpired_knowledge() -> None:
    authority = FallbackAuthority()
    service = KnowledgeRetrievalService(
        FakeEmbedder(), BrokenVectorStore(), KnowledgeRuntimeConfig(), authority
    )

    result = await service.search(
        KnowledgeQuery(query="开户", intents=("policy_explain",)),
        RequestContext(user_id="visitor-1", trace_id="trace", roles=("visitor",), data_scope="public"),
    )

    assert authority.calls == [(("fin_policy_collection",), 5)]
    assert result.degraded is True
    assert result.degradation_reason == "milvus_unavailable"
    assert result.hits[0].answer == "工作日确认"