#!/usr/bin/env python3

import boto3
from typing import List
import csv


def get_regions():
    client = boto3.client('ec2')
    return [item['RegionName'] for item in client.describe_regions()['Regions']]


def get_vpc_endpoints(client) -> List:
    paginator = client.get_paginator('describe_vpc_endpoints')
    page_iterator = paginator.paginate()
    return [item for sublist in page_iterator for item in sublist['VpcEndpoints']]


def get_interface_vpc_endpoints(vpc_endpoints) -> List:
    return [
        item for sublist in vpc_endpoints
        for item in sublist if item['VpcEndpointType'] == 'Interface'
    ]


def get_rows(vpc_endpoints_interface) -> List:
    rows: List = []
    for item in vpc_endpoints_interface:
        name_tag = [tag for tag in item['Tags'] if tag['Key'] == 'Name'][0]
        for entry in item['DnsEntries']:
            rows.append([
                name_tag['Value'],
                item['VpcEndpointId'],
                item['VpcId'],
                item['ServiceName'],
                entry['DnsName'],
                entry['HostedZoneId'],
            ])
    return rows


def get_profiles() -> List:
    return [
        'gdb-artistapp-dev',
        'gdb-artistapp-prod',
        'gdb-apollo-dev',
        'gdb-apollo-prod',
        'gdb-delphi-dev',
        'gdb-delphi-prod',
        'gdb-databricks-dev',
        'gdb-databricks-prod',
        'gdb-datasci-dev',
        'gdb-mct-dev',
        'gdb-mct-prod',
        'gdb-infra-dev',
        'gdb-infra-prod',
    ]


def main():
    profiles = get_profiles()
    regions = get_regions()
    sessions = []
    for profile in profiles:
        for region in regions:
            sessions.append(boto3.session.Session(
                profile_name=profile,
                region_name=region
            ))

    clients = []
    for session in sessions:
        clients.append(session.client('ec2'))

    vpc_endpoints = []
    for client in clients:
        vpc_endpoints.append(get_vpc_endpoints(client))

    vpc_endpoints_interface = get_interface_vpc_endpoints(vpc_endpoints)

    with open('vpc-endpoints.csv', 'w', newline='') as csvfile:
        writter = csv.writer(csvfile, delimiter=',',
                                quotechar='"', quoting=csv.QUOTE_MINIMAL)
        writter.writerow(['Name', 'VpcEndpointId', 'VpcId', 'ServiceName', 'DnsName', 'HostedZoneId'])
        for row in get_rows(vpc_endpoints_interface):
            writter.writerow(row)


if __name__ == '__main__':
    main()