#!/usr/bin/env python
"""
ec2_spot_price_list.py - Display the price summary of AWS EC2's spot instances across all regions
and availability zones.

Basic usage:
$ pip install numpy click boto3
$ python ec2_spot_price_list.py --instance-type m5.xlarge --product-description "Linux/UNIX (Amazon VPC)"

Copyright (C) 2019, Ikuya Yamada
"""

import collections
import boto3
import click
import numpy as np


@click.command()
@click.option('-t', '--instance-type', default=['m5.xlarge'], multiple=True)
@click.option('-d', '--product-description', default=['Linux/UNIX (Amazon VPC)'], multiple=True)
def main(instance_type, product_description):
    client = boto3.client('ec2', 'us-east-1')
    regions = [o['RegionName'] for o in client.describe_regions()['Regions']]
    price_data = collections.defaultdict(list)
    for region in regions:
        client = boto3.client('ec2', region)
        data = client.describe_spot_price_history(InstanceTypes=instance_type,
                                                  ProductDescriptions=product_description)
        for item in data['SpotPriceHistory']:
            key = (item['AvailabilityZone'], item['InstanceType'], item['ProductDescription'])
            price_data[key].append(float(item['SpotPrice']))

    for (zone, ins, desc), price_list in sorted(price_data.items(), key=lambda o: o[1][0]):
        print(f'Availability zone    {zone}')
        print(f'Instance type        {ins}')
        print(f'Current price        {price_list[0]:.2f}')
        print(f'Average price        {np.mean(price_list):.2f}')
        print(f'Max price            {max(price_list):.2f}')
        print('---')


if __name__ == '__main__':
    main()