import signal
import socket
import asyncio
import functools
from multiprocessing import Manager

import tqdm
import aiomultiprocess as aiomp
from dns.resolver import Resolver

import config
from config import logger
from common.database import Database


def dns_resolver():
    """
    dns解析器
    """
    resolver = Resolver()
    resolver.nameservers = config.resolver_nameservers
    resolver.timeout = config.resolver_timeout
    resolver.lifetime = config.resolver_lifetime
    return resolver


async def aiodns_query_a(hostname):
    """
    异步查询A记录

    :param str hostname: 主机名
    :return: 查询结果
    """
    try:
        loop = asyncio.get_event_loop()
        socket.setdefaulttimeout(20)
        # answer = await loop.getaddrinfo(hostname, 80)
        answer = await loop.run_in_executor(None,
                                            socket.gethostbyname_ex,
                                            hostname)
    except BaseException as e:
        logger.log('TRACE', e.args)
        answer = e
    return hostname, answer


def convert_results(result_list):
    """
    将结果列表类型转换为结果字典类型

    :param result_list: 待转换的结果列表
    :return: 转换后的结果字典
    """
    result_dict = {}
    for result in result_list:
        hostname, answer = result
        value_dict = {'ips': None, 'reason': None, 'valid': None}
        if isinstance(answer, tuple):
            value_dict['ips'] = str(answer[2])[1:-1]
            result_dict[hostname] = value_dict
        elif isinstance(answer, Exception):
            value_dict['reason'] = str(answer.args)
            value_dict['valid'] = 0
            result_dict[hostname] = value_dict
        else:
            value_dict['valid'] = 0
            result_dict[hostname] = value_dict
    return result_dict


def filter_subdomain(data_list):
    """
    过滤出无IPS值的子域到新的子域列表

    :param list data_list: 待过滤的数据列表
    :return: 符合条件的子域列表
    """
    subdomains = []
    for data in data_list:
        if not data.get('ips'):
            subdomain = data.get('subdomain')
            subdomains.append(subdomain)
    return subdomains


def update_data(data_list, results_dict):
    """
    更新解析结果

    :param list data_list: 待更新的数据列表
    :param dict results_dict: 解析结果字典
    :return: 更新后的数据列表
    """
    for index, data in enumerate(data_list):
        if not data.get('ips'):
            subdomain = data.get('subdomain')
            value_dict = results_dict.get(subdomain)
            data.update(value_dict)
            data_list[index] = data
    return data_list


def save_data(name, data):
    """
    保存解析结果到数据库

    :param str name: 保存表名
    :param list data: 待保存的数据
    """
    db = Database()
    db.drop_table(name)
    db.create_table(name)
    db.save_db(name, data, 'resolve')
    db.close()


def resolve_progress(pr_queue, total):
    """
    解析进度

    :param pr_queue: 进度队列
    :param int total: 待解析的子域个数
    """
    bar = tqdm.tqdm()
    bar.total = total
    bar.desc = 'Resolve Progress'
    bar.ncols = 80
    bar.smoothing = 0
    while True:
        done = pr_queue.qsize()
        bar.n = done
        bar.update()
        if done == total:
            break
    bar.close()


async def aio_query(pr_queue, hostname):
    """
    异步查询主机名的A记录

    :param pr_queue: 进度队列
    :param str hostname: 主机名
    :return: 查询结果
    """
    results = await aiodns_query_a(hostname)
    pr_queue.put(1)
    return results


async def aio_resolve(subdomain_list, process_num, coroutine_num):
    """
    异步解析子域A记录

    :param list subdomain_list: 待解析的子域列表
    :param int process_num: 解析进程数
    :param int coroutine_num: 每个解析进程下的协程数
    :return: 解析结果
    """
    m = Manager()
    pr_queue = m.Queue()
    loop = asyncio.get_event_loop()
    loop.run_in_executor(None, resolve_progress, pr_queue, len(subdomain_list))
    wrapped_query = functools.partial(aio_query, pr_queue)
    async with aiomp.Pool(processes=process_num,
                          childconcurrency=coroutine_num) as pool:
        results = await pool.map(wrapped_query, subdomain_list)
        return results


async def bulk_resolve(data_list):
    """
    批量解析A记录并返回解析结果

    :param list data_list: 待解析的数据列表
    :return: 解析得到的结果列表
    """
    logger.log('INFOR', '正在异步查询子域的A记录')
    # semaphore = asyncio.Semaphore(config.limit_resolve_conn)
    query_subdomains = filter_subdomain(data_list)
    process_num = config.brute_process_num
    coroutine_num = config.brute_coroutine_num
    results = await aio_resolve(query_subdomains, process_num, coroutine_num)
    results_dict = convert_results(results)
    data_list = update_data(data_list, results_dict)
    logger.log('INFOR', '完成异步查询子域的A记录')
    return data_list


def run_resolve(data):
    """
    调用子域解析入口函数

    :param list data: 待解析的子域数据列表
    :return: 解析得到的结果列表
    :rtype: list
    """
    loop = asyncio.get_event_loop()
    asyncio.set_event_loop(loop)
    resolve_coroutine = bulk_resolve(data)
    # 在关闭事件循环前加入一小段延迟让底层连接得到关闭的缓冲时间
    loop.run_until_complete(asyncio.sleep(0.25))
    return loop.run_until_complete(resolve_coroutine)