import json
import os
import threading
from pathlib import Path
from typing import Any, Optional

from oss.config import get_config
from oss.logger.logger import Log


class DataStore:
    """数据存储抽象接口

    默认实现使用 JSON 文件存储到 ~/.nebula/data/
    后续可由 data-store 插件替换为更完善的实现
    """

    def __init__(self):
        config = get_config()
        data_dir_env = os.environ.get("NEBULA_DATA_DIR", "")
        default_dir = Path(data_dir_env) if data_dir_env else Path.home() / ".nebula" / "data"
        self._base_dir = Path(config.get("DATA_DIR", str(default_dir)))
        self._base_dir.mkdir(parents=True, exist_ok=True)
        self._lock = threading.Lock()

    def _plugin_dir(self, plugin_name: str) -> Path:
        """获取插件专属数据目录"""
        pd = self._base_dir / plugin_name
        pd.mkdir(parents=True, exist_ok=True)
        return pd

    def save(self, plugin_name: str, key: str, data: Any) -> bool:
        """保存数据"""
        with self._lock:
            try:
                file_path = self._plugin_dir(plugin_name) / f"{key}.json"
                file_path.write_text(json.dumps(data, indent=2, ensure_ascii=False), encoding="utf-8")
                return True
            except Exception as e:
                Log.error("Core", f"数据存储保存失败 [{plugin_name}/{key}]: {e}")
                return False

    def load(self, plugin_name: str, key: str, default: Any = None) -> Any:
        """加载数据"""
        with self._lock:
            try:
                file_path = self._plugin_dir(plugin_name) / f"{key}.json"
                if file_path.exists():
                    return json.loads(file_path.read_text(encoding="utf-8"))
                return default
            except Exception as e:
                Log.error("Core", f"数据存储加载失败 [{plugin_name}/{key}]: {e}")
                return default

    def delete(self, plugin_name: str, key: str) -> bool:
        """删除数据"""
        with self._lock:
            try:
                file_path = self._plugin_dir(plugin_name) / f"{key}.json"
                if file_path.exists():
                    file_path.unlink()
                return True
            except Exception as e:
                Log.error("Core", f"数据存储删除失败 [{plugin_name}/{key}]: {e}")
                return False

    def list_keys(self, plugin_name: str) -> list[str]:
        """列出插件所有数据键"""
        pd = self._plugin_dir(plugin_name)
        if not pd.exists():
            return []
        return [f.stem for f in pd.glob("*.json")]

    def set_custom_path(self, plugin_name: str, custom_path: str) -> bool:
        """插件自定义存储路径（不能修改到项目目录内）"""
        path = Path(custom_path).expanduser().resolve()
        project_dir = Path.cwd().resolve()
        if str(path).startswith(str(project_dir)):
            Log.error("Core", f"插件 '{plugin_name}' 试图将数据存储到项目目录: {custom_path}")
            return False
        path.mkdir(parents=True, exist_ok=True)
        with self._lock:
            mapping_file = self._base_dir / "_custom_paths.json"
            mappings = {}
            if mapping_file.exists():
                try:
                    mappings = json.loads(mapping_file.read_text())
                except (json.JSONDecodeError, OSError):
                    pass  # 映射文件不存在或损坏是正常情况
            mappings[plugin_name] = str(path)
            mapping_file.write_text(json.dumps(mappings, indent=2))
        return True