import json
import pathlib

import boto3

client = boto3.client('iam')

account_id = boto3.client('sts').get_caller_identity().get('Account')
pathlib.Path(f'backups/{account_id}').mkdir(parents=True, exist_ok=True)

with open('policies_to_delete.txt') as f:
    for line in f.readlines():
        policy_arn = line.strip()
        print(f'Backing up policy {policy_arn}')
        policy = client.get_policy(PolicyArn=policy_arn)
        policy_name = policy['Policy']['PolicyName']
        default_version_id = policy['Policy']['DefaultVersionId']

        policy_version = client.get_policy_version(
            PolicyArn=policy_arn,
            VersionId=default_version_id
        )

        policy_document = policy_version['PolicyVersion']['Document']
        with open(f'backups/{account_id}/{policy_name}.json', 'w') as doc:
            doc.write(json.dumps(policy_document))

        print(f'Deleting policy {policy_name}')
        for policy_version_page in client.get_paginator('list_policy_versions').paginate(PolicyArn=policy_arn):
            for version in policy_version_page['Versions']:
                if not version['IsDefaultVersion']:
                    client.delete_policy_version(
                        PolicyArn=policy_arn,
                        VersionId=version['VersionId']
                    )
        client.delete_policy(PolicyArn=policy_arn)