# coding:utf-8
import etcd3
import random
import functools
import time
from concurrent.futures import ThreadPoolExecutor
from loguru import logger


class EtcdClient(object):
    def __init__(self, **kwargs):
        etcd_server = kwargs.get("etcd_server")
        self._etcd_client = etcd3.client(**etcd_server)
        self._service_prefix = kwargs.get("service_prefix", "")
        if not self._service_prefix:
            assert ValueError("服务名称不能为空")
        self._retries = kwargs.get("retries", 5)
        self._refresh_time = kwargs.get("refresh_time", 1)
        self._timeout = kwargs.get("timeout", self._retries * self._refresh_time + 1)

    def acquire_addr(self, number):
        """
        随机获取服务地址
        :param number: addr数量
        :return:
        """
        services = self._etcd_client.get_prefix(self._service_prefix)
        services = list(services) if services else []
        if not services:
            logger.warning("服务不存在")
            return []
        services = [service[0].decode("utf-8") for service in services if service]
        choices = random.choices(services, k=number)
        return choices

    def start(self, func):
        """
        单个执行
        :param func:
        :return:
        """

        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            param = kwargs.get("param")
            hosts = []
            start_time = time.time()
            for count in range(self._retries):
                hosts = self.acquire_addr(1)
                if hosts or time.time() - start_time > self._timeout:
                    break
                else:
                    time.sleep(self._refresh_time)
            hosts = hosts if hosts else "400"
            return func(param, hosts[0], *args, **kwargs)

        return wrapper

    def start_patch(self, thread_number=3):
        """
        # 并行执行任务
        :param thread_number:线程数
        :return:
        """

        def execute(func):
            @functools.wraps(func)
            def wrapper(*args, **kwargs):
                params = kwargs.get("params")
                if not params:
                    params = [None]
                host_count = len(params)
                hosts = []
                start_time = time.time()
                for count in range(self._retries):
                    hosts = self.acquire_addr(host_count)
                    if hosts or time.time() - start_time > self._timeout:
                        break
                    else:
                        time.sleep(self._refresh_time)
                if not hosts:
                    hosts = ["400"] * len(params)
                with ThreadPoolExecutor(max_workers=thread_number) as pool:
                    result = pool.map(func, params, hosts)
                return list(result)

            return wrapper

        return execute