import threading
import tomllib
from pathlib import Path
from tempfile import TemporaryDirectory
from unittest.mock import patch

from app.config import config
from app.models.llm_provider import LLM_PROVIDER_REGISTRY


class TestConfigPersistence:
    @staticmethod
    def _load_example_config():
        config_path = Path(__file__).resolve().parents[2] / "config.example.toml"
        return tomllib.loads(config_path.read_text(encoding="utf-8"))

    def test_example_config_documents_runtime_settings(self):
        """示例配置应展示用户需要手工维护的服务、素材和高级运行参数。"""
        example_config = self._load_example_config()
        app_config = example_config["app"]

        assert example_config["listen_host"] == "0.0.0.0"
        assert example_config["listen_port"] == 8080
        assert example_config["log_level"] == "DEBUG"
        assert app_config["video_source"] in {"pexels", "pixabay", "coverr", "local"}
        assert "match_materials_to_script" in app_config
        assert example_config["whisper"]["device"] == "cpu"

    def test_example_config_covers_llm_provider_registry(self):
        """Registry 中可配置的 Provider 字段必须能在示例文件中被发现。"""
        app_config = self._load_example_config()["app"]

        for provider in LLM_PROVIDER_REGISTRY:
            if provider.show_api_key:
                assert provider.config_key("api_key") in app_config
            if provider.show_base_url:
                assert provider.config_key("base_url") in app_config
            if provider.requires_model_name:
                assert provider.config_key("model_name") in app_config
            for field in provider.extra_fields:
                assert provider.config_key(field.config_suffix) in app_config

    def test_upload_post_settings_belong_to_app_section(self):
        """发布配置必须位于 app 节点，确保示例文件与运行时读取路径一致。"""
        example_config = self._load_example_config()
        upload_post_keys = {
            "upload_post_enabled",
            "upload_post_api_key",
            "upload_post_username",
            "upload_post_platforms",
            "upload_post_auto_upload",
            "upload_post_youtube_privacy_status",
        }

        assert upload_post_keys <= example_config["app"].keys()
        assert upload_post_keys.isdisjoint(example_config.get("ui", {}).keys())

    def test_save_config_uses_parseable_atomic_output(self):
        """
        配置保存先写临时文件再原子替换。测试同时确认输出仍是合法 TOML，
        且成功保存后不会在配置目录遗留临时文件。
        """
        original_cfg = dict(config._cfg)
        original_app = dict(config.app)
        try:
            with TemporaryDirectory() as temp_dir:
                config_path = Path(temp_dir) / "config.toml"
                config.app["atomic_save_test"] = "ok"
                with (
                    patch.object(config, "root_dir", temp_dir),
                    patch.object(config, "config_file", str(config_path)),
                ):
                    config.save_config()

                saved_config = tomllib.loads(config_path.read_text(encoding="utf-8"))
                assert saved_config["app"]["atomic_save_test"] == "ok"
                assert list(Path(temp_dir).glob(".config-*.toml.tmp")) == []
        finally:
            config.app.clear()
            config.app.update(original_app)
            config._cfg.clear()
            config._cfg.update(original_cfg)

    def test_runtime_config_lock_blocks_concurrent_config_writes(self):
        """长任务持有运行锁时，其它会话不能在任务中途改写全局配置。"""
        write_started = threading.Event()
        write_finished = threading.Event()

        def update_config():
            write_started.set()
            config.app["runtime_lock_test"] = "updated"
            write_finished.set()

        config.app.pop("runtime_lock_test", None)
        with config.runtime_config_lock():
            worker = threading.Thread(target=update_config)
            worker.start()
            assert write_started.wait(timeout=1)
            assert not write_finished.wait(timeout=0.05)

        worker.join(timeout=1)
        assert write_finished.is_set()
        config.app.pop("runtime_lock_test", None)