import sys
import time
import alb_utils
import gateway_config
import logging

logging.basicConfig(level=logging.INFO,
                    format='%(asctime)s %(filename)s[line:%(lineno)d] %(levelname)s %(message)s',
                    datefmt='%a, %d %b %Y %H:%M:%S')


def remove_instances(ecs_client, alb_client, instance_ids, port):
    """
    停止并释放机器
    :param ecs_client: 创建客户端
    :param alb_client: ALB 客户端
    :param instance_ids: instanceId 类型列表
    :param port: 后端服务器使用的端口
    :return: None
    """
    # 1. 摘除流量
    weight_list = [(0, 20)]  # 设置权重为0，等待20秒
    try:
        alb_utils.update_server_group_servers_attribute(alb_client,
                                                    gateway_config.server_group_id_list,
                                                    instance_id_list=instance_ids,
                                                    weight_list=weight_list,
                                                    port=port)
    except Exception as e:
        logging.error(f"Failed to set instance weight: {e}")
        sys.exit()

    # 等待 ALB 更新权重
    time.sleep(20)

    # 2. 从 ALB 服务器组中移除实例
    # for server_group_id in gateway_config.server_group_id_list:
    try:
        alb_utils.remove_servers_from_server_group(alb_client=alb_client,
                                               server_group_id_list=gateway_config.server_group_id_list,
                                               instance_ids=instance_ids, port=port)
        logging.info(
            f"Successfully removed count:{len(instance_ids)} instance_ids:  {instance_ids} from server group {gateway_config.server_group_id_list}.")
    except Exception as e:
        logging.error(
            f"Failed to remove count:{len(instance_ids)} instance_ids: {instance_ids} from server group {gateway_config.server_group_id_list}: {e}")

    logging.info(f"Remove from ALB finished, count:{len(instance_ids)} instances: {instance_ids}")

    # 3. 停止机器
    alb_utils.stop_instances(ecs_client=ecs_client, instance_ids=instance_ids)
    # stop_response = alb_utils.stop_instances(ecs_client=ecs_client, instance_ids=instance_ids)
    # if stop_response.get('Code') is None:
    #     logging.info(f"Instances stop finished, instances: {instance_ids}")
    # else:
    #     logging.error(f"Failed to stop instances: {stop_response}")
    #     sys.exit()

    # 4. 判断机器运行状态是否为 Stopped
    stopped_instances = alb_utils.get_instances_status(ecs_client=ecs_client, instance_ids=instance_ids)
    # while True:
    #     response = alb_utils.get_instances_status(ecs_client=ecs_client, instance_ids=instance_ids)
    #     if response.get('Code') is None:
    #         instances_list = response.get('InstanceStatuses').get('InstanceStatus')
    #         stopped_instances = [instance.get('InstanceId') for instance in instances_list if
    #                              instance.get('Status') == 'Stopped']
    #         if len(stopped_instances) == len(instance_ids):
    #             logging.info(f"Instances stopped status set success, instances: {stopped_instances}")
    #             break
    #         else:
    #             logging.info(f"Stopped instances count = {len(stopped_instances)}, instances: {stopped_instances}")
    #             time.sleep(5)
    #     else:
    #         logging.error(response)
    #         sys.exit()

    # 5. 释放机器
    alb_utils.release_instances(ecs_client=ecs_client, instance_ids=stopped_instances)
    # release_response = alb_utils.release_instances(ecs_client=ecs_client, instance_ids=stopped_instances)
    # if release_response.get('Code') is None:
    #     logging.info(f"Release instances finished, instances: {stopped_instances}")
    # else:
    #     logging.error(f"Release instances fail!!!")
    #     sys.exit()


def main():
    try:
        alb_client = alb_utils.connect_alb_client(
            access_key_id=gateway_config.alb_client_params['access_key_id'],
            access_key_secret=gateway_config.alb_client_params['access_key_secret'],
            endpoint=gateway_config.alb_client_params['endpoint']
        )

        ecs_client = alb_utils.connect_client(
            access_key_id=gateway_config.ecs_client_params['access_key_id'],
            access_key_secret=gateway_config.ecs_client_params['access_key_secret'],
            region_id=gateway_config.ecs_client_params['region_id']
        )

        # 获取指定释放的机器数量
        reduce_count = int(sys.argv[1])
        logging.info(f"reduce_count: {reduce_count}")

        # 获取 ALB 下所有机器
        online_instance_ids = alb_utils.list_server_group_servers(alb_client=alb_client,
                                                              server_group_id=gateway_config.server_group_id_list[
                                                                  0])
        online_instance_count = len(online_instance_ids)
        logging.info(f"online instance count: {online_instance_count} instance_ids: {online_instance_ids}")

        if online_instance_count - reduce_count < 10:
            logging.error("缩容后服务器数量不能小于10台")
            sys.exit()

        # 获取前 count 台机器进行释放
        reduce_instance_ids = online_instance_ids[:reduce_count]
        logging.info(f"reduce instances count = {len(reduce_instance_ids)} instances: {reduce_instance_ids}")

        # 停止并释放机器
        remove_instances(ecs_client=ecs_client, alb_client=alb_client, instance_ids=reduce_instance_ids,
                         port=gateway_config.port)
        logging.info(f"stop & release instances end!")
    except Exception as e:
        logging.error(e)
        sys.exit()


if __name__ == '__main__':
    main()