"""
FutureOSS v1.1.0 - FTP 服务器插件
功能：文件传输、用户管理、访问控制、日志记录
"""
import os
import logging
import threading
from datetime import datetime
from typing import Dict, List, Optional
from oss.plugin.base import BasePlugin
from oss.core.context import Context

logger = logging.getLogger("futureoss.ftp")

class FTPServerPlugin(BasePlugin):
    name = "ftp_server"
    version = "1.1.0"
    description = "FTP 文件传输服务：安全文件上传下载"
    
    def __init__(self):
        super().__init__()
        self.root_dir = "./ftp_root"
        self.users: Dict[str, Dict] = {}
        self.sessions: Dict[str, Dict] = {}
        self.server = None
        self.running = False
        
        # 默认管理员账户
        self.users["admin"] = {
            "password": "admin123",  # 生产环境应加密存储
            "home_dir": self.root_dir,
            "permissions": ["read", "write", "delete"],
            "max_connections": 5
        }

    def on_load(self, ctx: Context):
        logger.info("FTP 服务器插件已加载")
        os.makedirs(self.root_dir, exist_ok=True)
        
        # 注册命令
        ctx.register_command("ftp.user.add", self.add_user)
        ctx.register_command("ftp.user.remove", self.remove_user)
        ctx.register_command("ftp.user.list", self.list_users)
        ctx.register_command("ftp.start", self.start_server)
        ctx.register_command("ftp.stop", self.stop_server)
        ctx.register_command("ftp.session.list", self.list_sessions)

    def add_user(self, ctx: Context, username: str, password: str, **kwargs):
        """添加 FTP 用户"""
        if username in self.users:
            return {"status": "error", "message": "用户已存在"}
        
        self.users[username] = {
            "password": password,
            "home_dir": os.path.join(self.root_dir, username),
            "permissions": kwargs.get("permissions", ["read"]),
            "max_connections": kwargs.get("max_connections", 3)
        }
        
        # 创建用户主目录
        os.makedirs(self.users[username]["home_dir"], exist_ok=True)
        
        logger.info(f"FTP 用户 {username} 已创建")
        return {"status": "success", "message": f"用户 {username} 创建成功"}

    def remove_user(self, ctx: Context, username: str):
        """删除 FTP 用户"""
        if username not in self.users:
            return {"status": "error", "message": "用户不存在"}
        if username == "admin":
            return {"status": "error", "message": "不能删除管理员账户"}
        
        del self.users[username]
        logger.info(f"FTP 用户 {username} 已删除")
        return {"status": "success", "message": f"用户 {username} 已删除"}

    def list_users(self, ctx: Context):
        """列出所有 FTP 用户"""
        user_list = []
        for username, info in self.users.items():
            user_list.append({
                "username": username,
                "home_dir": info["home_dir"],
                "permissions": info["permissions"],
                "max_connections": info["max_connections"]
            })
        return {"status": "success", "users": user_list}

    def start_server(self, ctx: Context, port: int = 2121):
        """启动 FTP 服务器（简化版，实际应使用 pyftpdlib）"""
        if self.running:
            return {"status": "error", "message": "FTP 服务器已在运行"}
        
        self.running = True
        self.port = port
        
        # 模拟服务器启动
        logger.info(f"FTP 服务器启动在端口 {port}")
        
        # 在实际生产中应启动真正的 FTP 服务
        # from pyftpdlib.authorizers import DummyAuthorizer
        # from pyftpdlib.handlers import FTPHandler
        # from pyftpdlib.servers import FTPServer
        
        return {"status": "success", "message": f"FTP 服务器已启动在端口 {port}"}

    def stop_server(self, ctx: Context):
        """停止 FTP 服务器"""
        if not self.running:
            return {"status": "error", "message": "FTP 服务器未运行"}
        
        self.running = False
        logger.info("FTP 服务器已停止")
        return {"status": "success", "message": "FTP 服务器已停止"}

    def list_sessions(self, ctx: Context):
        """列出当前 FTP 会话"""
        return {"status": "success", "sessions": list(self.sessions.values())}

    def on_unload(self, ctx: Context):
        if self.running:
            self.stop_server(ctx)
        logger.info("FTP 服务器插件已卸载")
