"""知识统计 API 测试（GET /api/v1/knowledge/stats）

两层覆盖：
1. TestClient + monkeypatch 注入假 Qdrant 服务：响应结构与异常路径
2. 真实内存 Qdrant（location=":memory:"）集成：stats 数值与实际写入一致
"""

from collections.abc import Iterator
from typing import Any

import pytest
from fastapi.testclient import TestClient
from qdrant_client import AsyncQdrantClient

from app.api.v1 import knowledge as knowledge_module
from app.config import settings
from app.main import app
from app.services.qdrant import (
    COLLECTION_CHUNKS,
    COLLECTION_L1,
    COLLECTION_L2,
    COLLECTION_L3,
    QdrantService,
)

DIM = settings.embedding_dimension


def _dense(seed: float) -> list[float]:
    """构造确定性 dense 向量"""
    vec = [0.0] * DIM
    vec[0] = seed
    vec[1] = 1.0 - seed
    vec[2] = seed * 0.5
    vec[3] = 0.1
    return vec


@pytest.fixture
def client(monkeypatch: pytest.MonkeyPatch) -> Iterator[TestClient]:
    """TestClient，lifespan 中的 Qdrant 集合初始化替换为空操作"""

    async def _noop_ensure_collections(self: QdrantService) -> None:
        return None

    monkeypatch.setattr(QdrantService, "ensure_collections", _noop_ensure_collections)
    with TestClient(app) as test_client:
        yield test_client


class _FakeQdrantService:
    """假 Qdrant 服务：固定集合计数，scroll_l1 分 2 页返回类目"""

    COUNTS = {COLLECTION_L1: 3, COLLECTION_L2: 6, COLLECTION_L3: 4, COLLECTION_CHUNKS: 9}
    PAGES = [
        ([{"category": "技术文档"}, {"category": "技术文档"}], "cursor-1"),
        ([{"category": "uncategorized"}], None),
    ]

    async def count(self, collection: str) -> int:
        return self.COUNTS[collection]

    async def scroll_l1(
        self, limit: int = 100, offset: str | None = None
    ) -> tuple[list[dict[str, Any]], str | None]:
        assert limit == 100
        return self.PAGES[0] if offset is None else self.PAGES[1]


class _FailingQdrantService:
    """count 即抛异常的假服务，用于验证错误包装"""

    async def count(self, collection: str) -> int:
        raise RuntimeError("qdrant 连接失败")

    async def scroll_l1(
        self, limit: int = 100, offset: str | None = None
    ) -> tuple[list[dict[str, Any]], str | None]:
        raise RuntimeError("qdrant 连接失败")


def test_stats_ok(client: TestClient, monkeypatch: pytest.MonkeyPatch) -> None:
    """正常返回：四字段结构完整，数值来自假服务，类目跨页聚合"""
    monkeypatch.setattr(knowledge_module, "_get_qdrant", lambda: _FakeQdrantService())

    resp = client.get("/api/v1/knowledge/stats")

    assert resp.status_code == 200
    body = resp.json()
    assert body["code"] == 0
    data = body["data"]
    assert set(data.keys()) == {"collections", "categories", "uncategorized_count", "documents_total"}
    assert data["collections"] == {"doc_l1": 3, "doc_l2": 6, "doc_l3": 4, "chunks": 9}
    assert data["categories"] == {"技术文档": 2, "uncategorized": 1}
    assert data["uncategorized_count"] == 1
    assert data["documents_total"] == 3


def test_stats_qdrant_error(client: TestClient, monkeypatch: pytest.MonkeyPatch) -> None:
    """Qdrant 异常 → code 2000 统一错误响应"""
    monkeypatch.setattr(knowledge_module, "_get_qdrant", lambda: _FailingQdrantService())

    resp = client.get("/api/v1/knowledge/stats")

    assert resp.status_code == 200
    body = resp.json()
    assert body["code"] == 2000
    assert body["data"] is None
    assert "获取知识库统计失败" in body["message"]


@pytest.fixture
async def memory_service() -> QdrantService:
    """真实内存 Qdrant 服务，集合并写入 3 篇文档与若干 chunk"""
    service = QdrantService(client=AsyncQdrantClient(location=":memory:"))
    await service.ensure_collections()

    # 3 篇 L1：2 篇同类目 + 1 篇 uncategorized
    await service.upsert_l1(
        doc_id="doc-a",
        title="标题A",
        summary="总结A",
        category="技术文档",
        tags=["api"],
        dense_vector=_dense(0.9),
    )
    await service.upsert_l1(
        doc_id="doc-b",
        title="标题B",
        summary="总结B",
        category="技术文档",
        tags=["sdk"],
        dense_vector=_dense(0.8),
    )
    await service.upsert_l1(
        doc_id="doc-c",
        title="标题C",
        summary="总结C",
        category="uncategorized",
        tags=[],
        dense_vector=_dense(0.7),
    )
    # 5 个 chunk（doc-a 3 个、doc-c 2 个）
    chunks = [
        {
            "doc_id": doc_id,
            "chunk_index": i,
            "text": f"chunk{i}-{doc_id}",
            "section_path": "1",
            "title": f"标题-{doc_id}",
            "category": category,
            "tags": [],
            "dense_vector": _dense(0.5 + i * 0.1),
        }
        for doc_id, category, n in (("doc-a", "技术文档", 3), ("doc-c", "uncategorized", 2))
        for i in range(n)
    ]
    await service.upsert_chunks(chunks)
    return service


async def test_stats_with_real_memory_qdrant(
    memory_service: QdrantService, monkeypatch: pytest.MonkeyPatch
) -> None:
    """stats 数值与真实内存 Qdrant 写入一致（直接调路由处理函数）"""
    monkeypatch.setattr(knowledge_module, "_get_qdrant", lambda: memory_service)

    body = await knowledge_module.knowledge_stats()

    assert body["code"] == 0
    data = body["data"]
    assert data["collections"] == {"doc_l1": 3, "doc_l2": 0, "doc_l3": 0, "chunks": 5}
    assert data["documents_total"] == 3
    assert data["categories"] == {"技术文档": 2, "uncategorized": 1}
    assert data["uncategorized_count"] == 1