import boto3
import argparse
import sys
import json
import time
import datetime
from threading import Thread
from Queue import Queue
import base64

from utils import utils

class InstanceResource:
    ON_DEMAND = 1
    SPOT_INSTANCE = 2
    SPOT_FLEET = 3

with open("user-data.sh", "r") as userdata_file:
    USER_DATA = userdata_file.read()

IAM_INSTANCE_PROFILE = 'BenchMarkCodeDeployInstanceProfile'
time_stamp = time.time()
CURRENT_SESSION = datetime.datetime.fromtimestamp(
    time_stamp).strftime('%H-%M-%S-%Y-%m-%d')
NODE_NAME_SUFFIX = "NODE-" + CURRENT_SESSION

def run_one_region_instances(config, region_number, number_of_instances, instance_resource=InstanceResource.ON_DEMAND):
    region_name = config[region_number][utils.REGION_NAME]
    # Create session.
    session = boto3.Session(region_name=region_name)
    # Create a client.
    ec2_client = session.client('ec2')

    if instance_resource == InstanceResource.ON_DEMAND:
        node_name_tag = create_instances(
            config, ec2_client, region_number, int(number_of_instances))
        print("Created %s in region %s" % (node_name_tag, region_number))
        return node_name_tag
    else:
        return None


def create_instances(config, ec2_client, region_number, number_of_instances):
    node_name_tag = region_number + "-" + NODE_NAME_SUFFIX
    print("Creating node_name_tag: %s" % node_name_tag)
    available_zone = utils.get_one_availability_zone(ec2_client)
    print("Looking at zone %s to create instances." % available_zone)

    ec2_client.run_instances(
        MinCount=number_of_instances,
        MaxCount=number_of_instances,
        ImageId=config[region_number][utils.REGION_AMI],
        Placement={
            'AvailabilityZone': available_zone,
        },
        SecurityGroups=[config[region_number][utils.REGION_SECURITY_GROUP]],
        IamInstanceProfile={
            'Name': IAM_INSTANCE_PROFILE
        },
        KeyName=config[region_number][utils.REGION_KEY],
        UserData=USER_DATA,
        InstanceType=utils.INSTANCE_TYPE,
        TagSpecifications=[
            {
                'ResourceType': 'instance',
                'Tags': [
                    {
                        'Key': 'Name',
                        'Value': node_name_tag
                    },
                ]
            },
        ],
    )

    count = 0
    while count < 40:
        time.sleep(5)
        print("Waiting ...")
        ip_list = utils.collect_public_ips_from_ec2_client(ec2_client, node_name_tag)
        if len(ip_list) == number_of_instances:
            print("Created %d instances" % number_of_instances)
            return node_name_tag
        count = count + 1
    print("Can not create %d instances" % number_of_instances)
    return None

if __name__ == "__main__":
    parser = argparse.ArgumentParser(
        description='This script helps you start instances across multiple regions')
    parser.add_argument('--regions', type=str, dest='regions',
                        default='3', help="Supply a csv list of all regions")
    parser.add_argument('--instances', type=str, dest='numInstances',
                        default='1', help='number of instances')
    parser.add_argument('--configuration', type=str,
                        dest='config', default='configuration.txt')
    parser.add_argument('--instance_output', type=str, dest='instance_output',
                        default='instance_output.txt', help='the file to append or write')
    parser.add_argument('--append', dest='append', type=bool, default=False,
                        help='append to the current instance_output')
    args = parser.parse_args()
    config = utils.read_region_config(args.config)
    region_list = args.regions.split(',')
    instances_list = args.numInstances.split(',')
    assert len(region_list) == len(instances_list), "number of regions: %d != number of instances per region: %d" % (len(region_list), len(instances_list))

    with open(args.instance_output, "a" if args.append else "w") as fout:
        for i in range(len(region_list)):
            region_number = region_list[i]
            number_of_instances = instances_list[i]
            node_name_tag = run_one_region_instances(config, region_number, number_of_instances, InstanceResource.ON_DEMAND)
            if node_name_tag:
                print("Managed to create instances for region %s" % region_number )
                fout.write("%s %s\n" % (node_name_tag, region_number))
            else:
                print("Failed to create instances for region %s" % region_number )