import asyncio
import time
from functools import wraps
from typing import Callable, cast, Optional, Any

from telegram import Update
from telegram.ext import filters, CallbackContext

from utils.log import logger

_lock = asyncio.Lock()


def restricts(restricts_time: int = 9, restricts_time_of_groups: Optional[int] = None, return_data: Any = None,
              without_overlapping: bool = False):
    """用于装饰在指定函数预防洪水攻击的装饰器

    被修饰的函数生声明必须为

    async def command_func(update, context)
    或
    async def command_func(self, update, context

    如果修饰的函数属于
    ConversationHandler
    参数
    return_data
    必须传入
    ConversationHandler.END

    我真™是服了某些闲着没事干的群友了

    :param restricts_time: 基础限制时间
    :param restricts_time_of_groups: 对群限制的时间
    :param return_data: 返回的数据对于 ConversationHandler 需要传入 ConversationHandler.END
    :param without_overlapping: 两次命令时间不覆盖，在上一条一样的命令返回之前，忽略重复调用
    """

    def decorator(func: Callable):
        @wraps(func)
        async def restricts_func(*args, **kwargs):
            if len(args) == 3:
                # self update context
                _, update, context = args
            elif len(args) == 2:
                # update context
                update, context = args
            else:
                return await func(*args, **kwargs)
            update = cast(Update, update)
            context = cast(CallbackContext, context)
            message = update.effective_message
            user = update.effective_user

            _restricts_time = restricts_time
            if restricts_time_of_groups is not None:
                if filters.ChatType.GROUPS.filter(message):
                    _restricts_time = restricts_time_of_groups

            async with _lock:
                user_lock = context.user_data.get("lock")
                if user_lock is None:
                    user_lock = context.user_data["lock"] = asyncio.Lock()

            # 如果上一个命令还未完成，忽略后续重复调用
            if without_overlapping and user_lock.locked():
                logger.warning(f"用户 {user.full_name}[{user.id}] 触发 overlapping 该次命令已忽略")
                return return_data

            async with user_lock:
                command_time = context.user_data.get("command_time", 0)
                count = context.user_data.get("usage_count", 0)
                restrict_since = context.user_data.get("restrict_since", 0)

                # 洪水防御
                if restrict_since:
                    if (time.time() - restrict_since) >= 60 * 5:
                        del context.user_data["restrict_since"]
                        del context.user_data["usage_count"]
                    else:
                        return return_data
                else:
                    if count >= 6:
                        context.user_data["restrict_since"] = time.time()
                        await message.reply_text("你已经触发洪水防御，请等待5分钟")
                        logger.warning(f"用户 {user.full_name}[{user.id}] 触发洪水限制 已被限制5分钟")
                        return return_data
                # 单次使用限制
                if command_time:
                    if (time.time() - command_time) <= _restricts_time:
                        context.user_data["usage_count"] = count + 1
                    else:
                        if count >= 1:
                            context.user_data["usage_count"] = count - 1
                context.user_data["command_time"] = time.time()

                # 只需要给 without_overlapping 的代码加锁运行
                if without_overlapping:
                    return await func(*args, **kwargs)

            if count > 1:
                await asyncio.sleep(count)
            return await func(*args, **kwargs)

        return restricts_func

    return decorator