import json
import os
import unittest
from unittest.mock import MagicMock, patch

from services.llm_service import LlmServiceError, llm_service


class _FakeResponse:
    def __init__(self, payload: dict):
        self._payload = json.dumps(payload).encode("utf-8")

    def read(self):
        return self._payload

    def __enter__(self):
        return self

    def __exit__(self, exc_type, exc, tb):
        return False


class LlmServiceTest(unittest.TestCase):
    def tearDown(self):
        get_settings = __import__("config", fromlist=["get_settings"]).get_settings
        get_settings.cache_clear()

    def test_not_configured_without_api_key(self):
        with patch.dict(os.environ, {"DEEPSEEK_API_KEY": ""}, clear=False):
            __import__("config", fromlist=["get_settings"]).get_settings.cache_clear()
            self.assertFalse(llm_service.is_configured())

    @patch("services.llm_service.urllib.request.urlopen")
    def test_enhance_wiki_page_returns_model_content(self, urlopen_mock: MagicMock):
        with patch.dict(os.environ, {"DEEPSEEK_API_KEY": "test-key"}, clear=False):
            __import__("config", fromlist=["get_settings"]).get_settings.cache_clear()
            urlopen_mock.return_value = _FakeResponse(
                {
                    "choices": [
                        {"message": {"content": "# demo\n\n整理后的知识页。"}},
                    ]
                }
            )
            content = llm_service.enhance_wiki_page(title="demo", draft_markdown="# draft")
            self.assertIn("整理后的知识页", content)

    def test_missing_api_key_raises(self):
        with patch.dict(os.environ, {"DEEPSEEK_API_KEY": ""}, clear=False):
            __import__("config", fromlist=["get_settings"]).get_settings.cache_clear()
            with self.assertRaises(LlmServiceError):
                llm_service.enhance_wiki_page(title="demo", draft_markdown="# draft")

    @patch("services.llm_service.urllib.request.urlopen")
    def test_parse_word_pairs_from_text(self, urlopen_mock: MagicMock):
        with patch.dict(os.environ, {"DEEPSEEK_API_KEY": "test-key"}, clear=False):
            __import__("config", fromlist=["get_settings"]).get_settings.cache_clear()
            urlopen_mock.return_value = _FakeResponse(
                {
                    "choices": [
                        {
                            "message": {
                                "content": (
                                    '{"items":[{"en":"apple","zh":"苹果"},'
                                    '{"en":"banana","zh":"香蕉"}]}'
                                )
                            }
                        },
                    ]
                }
            )
            pairs = llm_service.parse_word_pairs_from_text("apple 苹果\nbanana 香蕉")
            self.assertEqual(len(pairs), 2)
            self.assertEqual(pairs[0]["en"], "apple")
            self.assertEqual(pairs[0]["zh"], "苹果")


if __name__ == "__main__":
    unittest.main()