# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
# SPDX-License-Identifier: MIT-0

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# INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
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import sys
import boto3
import json
import os
from botocore.exceptions import ClientError

'''
Tag all objects and move to the manual review S3 bucket if sensitive data 
found. Move files to the scanned data S3 bucket if no sensitive data found. 
Trigger a manual approval notification to SNS topic if sensitive data is 
found.

This proof of concept is used as part of a data pipeline workflow as part of
the data ingestion pipeline. 
'''

sns_client = boto3.client('sns')
s3_client = boto3.client('s3')
step_function_client = boto3.client('stepfunctions')

def lambda_handler(event, context):    
    api_allow_endpoint = os.environ['apiAllowEndpoint']
    api_deny_endpoint = os.environ['apiDenyEndpoint']
    sns_topic_arn = os.environ['snsTopicArn']
    target_bucket_name = os.environ['targetS3Bucket']
    src_bucket_name = os.environ['sourceS3Bucket']
    target_scanned_bucket_name = os.environ['targetScannedS3Bucket']

    prefix = event['Input']['id']
    s3_key_names = event['Input']['macieFindingsInfo']['Payload']
    check_key = ''

    try:
        for s3_key_name in s3_key_names:
            response = s3_client.put_object_tagging(
                Bucket = src_bucket_name,
                Key = s3_key_name,
                Tagging = {
                    'TagSet': [
                        {
                            'Key': 'SensitiveDataFound',
                            'Value': 'true'
                        },
                        {
                            'Key': 'WorkflowId',
                            'Value': prefix
                        }
                    ]
                }
            )
            response = s3_client.copy_object(
                Bucket = target_bucket_name,
                CopySource = {
                    'Bucket': src_bucket_name,
                    'Key': s3_key_name
                },
                Key = s3_key_name
            )
            response = s3_client.delete_object(
                Bucket=src_bucket_name,
                Key = s3_key_name
            )
    except Exception as e:
        print(f'Could not complete S3 object move')
        print(e)
        return

    try:
        paginator = s3_client.get_paginator('list_objects_v2')
        
        page_iterator = paginator.paginate(
            Bucket=src_bucket_name)
        for page in page_iterator:
            if ('Contents' in page):
                s3_keys_remaining = page['Contents']
            else:
                s3_keys_remaining = []
                
            for s3_key_info in s3_keys_remaining:
                object_tags = s3_client.get_object_tagging(
                    Bucket=src_bucket_name,
                    Key=s3_key_info['Key']
                )
                for tag_set in object_tags['TagSet']:
                    if tag_set['Key'] == 'WorkflowId':
                        check_key = tag_set['Value']

                if check_key == prefix:
                    response = s3_client.copy_object(
                        Bucket = target_scanned_bucket_name,
                        CopySource = {
                            'Bucket': src_bucket_name,
                            'Key': s3_key_info['Key']
                        },
                        Key = s3_key_info['Key']
                    )
                    response = s3_client.delete_object(
                        Bucket=src_bucket_name,
                        Key = s3_key_info['Key']
                    )
                    check_key = ''
                else:
                    print(f"Object tag not matching for {s3_key_info['Key']}")
    except Exception as e:
        print(f'Could not complete S3 object move')
        print(e)
        return

    try:
        response = sns_client.publish(
            TopicArn = sns_topic_arn,
            Subject = 'APPROVAL REQUIRED: Sensitive data identified in pipeline',
            Message = f'Sensitive data discovered in data pipeline run.\n\n'\
                f'Approve: {api_allow_endpoint}?token={event["token"]}\n\n'\
                f'Deny: {api_deny_endpoint}?token={event["token"]}\n\n'\
                f'Files: {s3_key_names}'
        )
    except Exception as e:
        print(f'Could not publish to SNS topic {sns_topic_arn}')
        print(e)
        return

    return