#!/usr/bin/python3

import boto3


def recurseChildren(ouid: str, level: int) -> None:
    """
    Recurse down the AWS organization tree and invoke printChildAccounts once
    the bottom has been reached

    :param ouid: Parent OUID
    :param level: Used internally for printing dots
    :return: None
    """
    global client
    children = client.list_organizational_units_for_parent(ParentId=ouid).get('OrganizationalUnits')
    if len(children) == 0:
        printChildAccounts(ouid, level)
        return
    else:
        if ouid.startswith('r'):
            printChildAccounts(ouid, level)
        for ou in children:
            print('.' * 2 * level, ou.get('Name'), ou.get('Id'))
            if ouid.startswith('ou'):
                printChildAccounts(ouid, level)
            recurseChildren(ou.get('Id'), level + 1)


def printChildAccounts(ouid: str, level: int) -> None:
    """
    Print child account details

    :param ouid: Parent OUID
    :param level: Used internally for printing dots
    :return: None
    """
    global client
    childAccounts = client.list_accounts_for_parent(ParentId=ouid).get('Accounts')
    for account in childAccounts:
        print('.' * 2 * level, account.get('Name'), account.get('Id'))
    return


if __name__ == '__main__':
    client = boto3.client('organizations')
    response = client.list_roots()
    rootId = response['Roots'][0]['Id']
    print('Root', rootId, sep=": ")
    recurseChildren(rootId, 1)