"""
运行时权限管理模块
管理员可通过 Bot 命令动态添加/删除用户和设置权限。
持久化存储在 permissions.json 中。
"""

import json
import threading
from pathlib import Path

_PROJECT_ROOT = Path(__file__).parent.parent
_PERM_FILE = _PROJECT_ROOT / "permissions.json"
_lock = threading.Lock()

# 所有可用命令列表（用于验证输入）
ALL_COMMANDS = {
    "start", "help", "register", "stop", "check",
    "accounts", "delete", "verify", "stats", "status",
    "mailstatus", "proxy", "proxytest", "proxystatus",
    "document",  # 文件上传
    "adduser", "removeuser", "setperm", "users",  # 管理命令
}


def _load() -> dict:
    """加载权限数据"""
    try:
        with open(_PERM_FILE, "r", encoding="utf-8") as f:
            return json.load(f)
    except (FileNotFoundError, json.JSONDecodeError):
        return {"users": {}}


def _save(data: dict):
    """保存权限数据"""
    with open(_PERM_FILE, "w", encoding="utf-8") as f:
        json.dump(data, f, ensure_ascii=False, indent=2)


def add_user(user_id: int, commands: list[str]) -> None:
    """添加用户或更新已有用户权限"""
    with _lock:
        data = _load()
        data["users"][str(user_id)] = {
            "commands": commands,
        }
        _save(data)


def remove_user(user_id: int) -> bool:
    """删除用户，返回是否成功"""
    with _lock:
        data = _load()
        key = str(user_id)
        if key in data["users"]:
            del data["users"][key]
            _save(data)
            return True
        return False


def set_commands(user_id: int, commands: list[str]) -> bool:
    """设置用户权限，返回是否成功（用户必须存在）"""
    with _lock:
        data = _load()
        key = str(user_id)
        if key not in data["users"]:
            return False
        data["users"][key]["commands"] = commands
        _save(data)
        return True


def get_user(user_id: int) -> dict | None:
    """获取单个用户信息"""
    with _lock:
        data = _load()
        return data["users"].get(str(user_id))


def list_users() -> dict[int, dict]:
    """列出所有运行时用户"""
    with _lock:
        data = _load()
        return {int(k): v for k, v in data["users"].items()}


def get_permissions_map() -> dict[int, set[str]]:
    """
    返回运行时权限映射：user_id → set[command_name]
    用于与 config.toml 的静态权限合并
    """
    with _lock:
        data = _load()
        result = {}
        for uid_str, info in data["users"].items():
            result[int(uid_str)] = set(info.get("commands", []))
        return result