"""知识库访问权限校验的单元测试。"""

from __future__ import annotations

import asyncio
from unittest.mock import AsyncMock, patch

import httpx
import pytest

from app.module.kg_graphrag.kb_access import KnowledgeBaseAccessValidator


@pytest.fixture
def validator() -> KnowledgeBaseAccessValidator:
    return KnowledgeBaseAccessValidator(
        base_url="http://test-backend:8080/api",
        timeout=5.0,
    )


def _run(coro):
    return asyncio.run(coro)


_FAKE_REQUEST = httpx.Request("GET", "http://test")


def _resp(status_code: int, *, json=None, text=None) -> httpx.Response:
    """创建带 request 的 httpx.Response。"""
    if json is not None:
        return httpx.Response(status_code, json=json, request=_FAKE_REQUEST)
    return httpx.Response(status_code, text=text or "", request=_FAKE_REQUEST)


# ---------------------------------------------------------------------------
# check_access 测试
# ---------------------------------------------------------------------------


class TestCheckAccess:
    """check_access 方法的测试。"""

    def test_access_granted(self, validator: KnowledgeBaseAccessValidator):
        """Java 返回 200 + code=200: 用户有权访问。"""
        mock_resp = _resp(200, json={"code": 200, "data": {"id": "kb-1", "name": "test-kb"}})
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            result = _run(validator.check_access("kb-1", "user-1"))

        assert result is True

    def test_access_granted_with_matching_collection(self, validator: KnowledgeBaseAccessValidator):
        """权限通过且 collection_name 与 KB name 一致：允许访问。"""
        mock_resp = _resp(200, json={"code": 200, "data": {"id": "kb-1", "name": "my-collection"}})
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            result = _run(validator.check_access(
                "kb-1", "user-1", collection_name="my-collection",
            ))

        assert result is True

    def test_access_denied_by_biz_code(self, validator: KnowledgeBaseAccessValidator):
        """Java 返回 HTTP 200 但 code != 200（权限不足 sys.0005）。"""
        mock_resp = _resp(200, json={"code": "sys.0005", "message": "权限不足"})
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            result = _run(validator.check_access("kb-1", "other-user"))

        assert result is False

    def test_access_denied_http_403(self, validator: KnowledgeBaseAccessValidator):
        """Java 返回 HTTP 403。"""
        mock_resp = _resp(403, text="Forbidden")
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            result = _run(validator.check_access("kb-1", "user-1"))

        assert result is False

    def test_kb_not_found_http_404(self, validator: KnowledgeBaseAccessValidator):
        """知识库不存在，Java 返回 404。"""
        mock_resp = _resp(404, text="Not Found")
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            result = _run(validator.check_access("nonexistent-kb", "user-1"))

        assert result is False

    def test_server_error_http_500(self, validator: KnowledgeBaseAccessValidator):
        """Java 后端返回 500。"""
        mock_resp = _resp(500, text="Internal Server Error")
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            result = _run(validator.check_access("kb-1", "user-1"))

        assert result is False

    def test_fail_close_on_connection_error(self, validator: KnowledgeBaseAccessValidator):
        """网络异常时 fail-close（拒绝访问），防止绕过权限校验。"""
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(side_effect=httpx.ConnectError("connection refused"))
            mock_get.return_value = mock_http

            result = _run(validator.check_access("kb-1", "user-1"))

        assert result is False

    def test_fail_close_on_timeout(self, validator: KnowledgeBaseAccessValidator):
        """超时时 fail-close（拒绝访问）。"""
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(side_effect=httpx.ReadTimeout("timeout"))
            mock_get.return_value = mock_http

            result = _run(validator.check_access("kb-1", "user-1"))

        assert result is False

    def test_request_headers(self, validator: KnowledgeBaseAccessValidator):
        """验证请求中携带正确的 X-User-Id header。"""
        mock_resp = _resp(200, json={"code": 200, "data": {}})
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            _run(validator.check_access("kb-123", "user-456"))

        call_kwargs = mock_http.get.call_args
        assert "/api/knowledge-base/kb-123" in call_kwargs.args[0]
        assert call_kwargs.kwargs["headers"]["X-User-Id"] == "user-456"

    def test_cross_user_access_denied(self, validator: KnowledgeBaseAccessValidator):
        """跨用户访问：用户 B 试图访问用户 A 的知识库，应被拒绝。

        模拟 Java 后端返回权限不足的业务错误。
        """
        # 用户 A 创建的 KB，用户 B 请求访问
        mock_resp = _resp(200, json={
            "code": "sys.0005",
            "message": "权限不足",
            "data": None,
        })
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            result = _run(validator.check_access("kb-user-a", "user-b"))

        assert result is False

        # 确认请求携带的是用户 B 的 ID
        call_kwargs = mock_http.get.call_args
        assert call_kwargs.kwargs["headers"]["X-User-Id"] == "user-b"

    def test_admin_access_granted(self, validator: KnowledgeBaseAccessValidator):
        """管理员访问其他用户的知识库：Java 侧管理员跳过 owner 校验。"""
        mock_resp = _resp(200, json={
            "code": 200,
            "data": {"id": "kb-user-a", "name": "用户A的知识库", "createdBy": "user-a"},
        })
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            result = _run(validator.check_access("kb-user-a", "admin-user"))

        # Java 侧管理员校验通过，返回 200 + code=200
        assert result is True


# ---------------------------------------------------------------------------
# collection_name 绑定校验测试
# ---------------------------------------------------------------------------


class TestCollectionNameBinding:
    """collection_name 与 knowledge_base_id 的绑定校验测试。

    防止用户提交合法的 KB ID 但篡改 collection_name 来读取其他
    知识库的 Milvus 数据。
    """

    def test_collection_name_mismatch_denied(self, validator: KnowledgeBaseAccessValidator):
        """KB-A 的 name='collection-a'，但请求传了 collection_name='collection-b'：拒绝。"""
        mock_resp = _resp(200, json={
            "code": 200,
            "data": {"id": "kb-a", "name": "collection-a"},
        })
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            result = _run(validator.check_access(
                "kb-a", "user-1", collection_name="collection-b",
            ))

        assert result is False

    def test_collection_name_none_skips_check(self, validator: KnowledgeBaseAccessValidator):
        """collection_name=None 时不做绑定校验（向后兼容）。"""
        mock_resp = _resp(200, json={
            "code": 200,
            "data": {"id": "kb-1", "name": "some-name"},
        })
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            # 不传 collection_name → 仅校验权限，不校验绑定
            result = _run(validator.check_access("kb-1", "user-1"))

        assert result is True

    def test_response_data_missing_name_denied(self, validator: KnowledgeBaseAccessValidator):
        """Java 响应 data 中没有 name 字段：fail-close 拒绝。"""
        mock_resp = _resp(200, json={
            "code": 200,
            "data": {"id": "kb-1"},
        })
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            result = _run(validator.check_access(
                "kb-1", "user-1", collection_name="any-collection",
            ))

        # data.name is None, doesn't match "any-collection" → denied
        assert result is False

    def test_response_data_null_denied(self, validator: KnowledgeBaseAccessValidator):
        """Java 响应 data 为 null：fail-close 拒绝。"""
        mock_resp = _resp(200, json={
            "code": 200,
            "data": None,
        })
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            result = _run(validator.check_access(
                "kb-1", "user-1", collection_name="any-collection",
            ))

        assert result is False

    def test_response_data_empty_dict_denied(self, validator: KnowledgeBaseAccessValidator):
        """Java 响应 data 为空 dict {}：fail-close 拒绝。"""
        mock_resp = _resp(200, json={
            "code": 200,
            "data": {},
        })
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            result = _run(validator.check_access(
                "kb-1", "user-1", collection_name="any-collection",
            ))

        assert result is False

    def test_cross_kb_collection_swap_denied(self, validator: KnowledgeBaseAccessValidator):
        """用户有权访问 KB-A（name='kb-a-data'），试图用 KB-A 的 ID 搭配 KB-B 的
        collection_name='kb-b-data'：应被拒绝。

        这是核心越权场景的完整模拟。
        """
        # 用户有权访问 KB-A
        mock_resp = _resp(200, json={
            "code": 200,
            "data": {"id": "kb-a", "name": "kb-a-data", "createdBy": "user-1"},
        })
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            # 但 collection_name 指向 KB-B 的数据
            result = _run(validator.check_access(
                "kb-a", "user-1", collection_name="kb-b-data",
            ))

        assert result is False

    def test_chinese_collection_name_match(self, validator: KnowledgeBaseAccessValidator):
        """中文 collection_name 精确匹配。"""
        mock_resp = _resp(200, json={
            "code": 200,
            "data": {"id": "kb-1", "name": "用户行为数据"},
        })
        with patch.object(validator, "_get_client") as mock_get:
            mock_http = AsyncMock()
            mock_http.get = AsyncMock(return_value=mock_resp)
            mock_get.return_value = mock_http

            result = _run(validator.check_access(
                "kb-1", "user-1", collection_name="用户行为数据",
            ))

        assert result is True