# ============================================================
# 混合嵌入降级黄金测试
# ============================================================
from __future__ import annotations

from server.knowledge.embedding import EmbeddingProvider, EmbeddingStore, _cosine
from server.knowledge.retrieval import hybrid_search


def test_embedding_provider_falls_back_to_none(monkeypatch):
    monkeypatch.setenv("EMBEDDING_PROVIDER", "off")
    monkeypatch.delenv("EMBEDDING_API_KEY", raising=False)
    monkeypatch.delenv("LLM_API_KEY", raising=False)
    p = EmbeddingProvider()
    assert p.backend == "none"
    assert p.enabled is False
    assert p.embed(["hello"]) is None


def test_cosine_and_store_search(tmp_path):
    store = EmbeddingStore(path=str(tmp_path / "emb.json"))
    store.upsert_many({
        "a:1": [1.0, 0.0, 0.0],
        "b:1": [0.0, 1.0, 0.0],
        "c:1": [0.9, 0.1, 0.0],
    })
    hits = store.search([1.0, 0.0, 0.0], top_k=2)
    assert hits[0][0] == "a:1"
    assert hits[0][1] == 1.0
    assert _cosine([1, 0], [0, 1]) == 0.0


def test_hybrid_search_works_without_vectors():
    units = [{
        "assetId": "x1", "title": "换线标准SOP", "kind": "sop", "version": "v1",
        "tags": ["换线"], "content": "产线换型必须遵守夜班不换线规定。",
        "chunkId": "c1", "heading": None, "page": None,
    }]
    hits = hybrid_search(units, "换线夜班", top_k=3)
    assert hits
    assert hits[0]["assetId"] == "x1"
    assert hits[0]["version"] == "v1"
    miss = hybrid_search(units, "quantum blockchain xyzzy", top_k=3)
    assert miss == []