from typing import Dict, List, Optional
from dataclasses import dataclass
from enum import Enum
import json
import os
from utils.logger import logger


@dataclass
class Permission:
    """权限类"""
    key: str
    name: str
    description: str
    value: int
    plugin_id: Optional[str] = None


class PermissionStatus(Enum):
    """权限状态枚举"""
    ENABLED = 1
    DISABLED = 0


class PermissionManager:
    """权限管理器（单例模式）"""
    _instance = None
    _initialized = False

    def __new__(cls):
        if cls._instance is None:
            cls._instance = super().__new__(cls)
        return cls._instance

    def __init__(self):
        if not self._initialized:
            self._permissions: Dict[str, Permission] = {}
            self._config_file = "config/permissions.json"
            self._load_permissions()
            self._initialized = True

    def _load_permissions(self):
        """从配置文件加载权限"""
        try:
            if os.path.exists(self._config_file):
                with open(self._config_file, 'r', encoding='utf-8') as f:
                    data = json.load(f)
                    for key, perm_data in data.items():
                        self._permissions[key] = Permission(**perm_data)
        except Exception as e:
            logger.error(f"加载权限配置失败: {e}")

    def _save_permissions(self):
        """保存权限到配置文件"""
        try:
            os.makedirs(os.path.dirname(self._config_file), exist_ok=True)
            with open(self._config_file, 'w', encoding='utf-8') as f:
                json.dump(
                    {k: v.__dict__ for k, v in self._permissions.items()},
                    f,
                    ensure_ascii=False,
                    indent=2
                )
        except Exception as e:
            logger.error(f"保存权限配置失败: {e}")

    def register_permission(
        self,
        key: str,
        name: str,
        description: str,
        plugin_id: Optional[str] = None
    ) -> Permission:
        """注册新权限"""
        if key in self._permissions:
            return self._permissions[key]

        value = len(self._permissions) + 1
        permission = Permission(
            key=key,
            name=name,
            description=description,
            value=value,
            plugin_id=plugin_id
        )
        self._permissions[key] = permission
        self._save_permissions()
        return permission

    def get_permission(self, key: str) -> Optional[Permission]:
        """获取权限"""
        return self._permissions.get(key)

    def get_permission_by_value(self, value: int) -> Optional[Permission]:
        """通过值获取权限"""
        for perm in self._permissions.values():
            if perm.value == value:
                return perm
        return None

    def get_all_permissions(self) -> List[Permission]:
        """获取所有权限"""
        return list(self._permissions.values())

    def get_plugin_permissions(self, plugin_id: str) -> List[Permission]:
        """获取插件的所有权限"""
        return [
            perm for perm in self._permissions.values()
            if perm.plugin_id == plugin_id
        ]

    def remove_permission(self, key: str) -> bool:
        """移除权限"""
        if key in self._permissions:
            del self._permissions[key]
            self._save_permissions()
            return True
        return False