"""Lambda smart_downloader function module."""
import logging

import boto3
import config
import sentry_sdk
from src import dynamodb_utils
from src import logic
from sentry_sdk.integrations.aws_lambda import AwsLambdaIntegration

# set logger level to INFO in order to see logs in CloudWatch
logging.getLogger().setLevel(logging.INFO)

logger = logging.getLogger(__name__)

if config.SENTRY_DSN:
    sentry_sdk.init(
        dsn=config.SENTRY_DSN,
        integrations=[
            AwsLambdaIntegration(),
        ],
    )
else:
    logger.warning('Initializing without sentry')


def handler(event, context):
    """Lambda entry point."""
    dynamodb_client = boto3.client('dynamodb',
                                   region_name=config.AWS_REGION)
    try:
        if 'Records' in event:
            # DynamoDB event https://docs.aws.amazon.com/lambda/latest/dg/with-ddb-example.html  # noqa:E501
            logger.info('DynamoDB event detected')
            for record in event['Records']:
                assert record['eventSource'] == 'aws:dynamodb'
                event_name = record['eventName']
                table_name = dynamodb_utils.get_table_name_from_arn(
                    record['eventSourceARN'])
                if not event_name == 'INSERT':
                    logger.info(f'Skipping eventName {event_name}')
                    continue
                dynamodb_record = record['dynamodb']
                download_request, key = dynamodb_utils.extract_download_request_from_dynamodb_item(  # noqa:E501
                    dynamodb_record)
                to_update = {'status': 'PROCESSING'}
                update_kwargs = dynamodb_utils.build_update_item_expression_kwargs(  # noqa:E501
                    to_update)
                dynamodb_client.update_item(
                    TableName=table_name,
                    Key=key,
                    **update_kwargs
                )

                to_update = {}
                try:
                    download_response = logic.parallel_download_curl_to_s3(
                        tasks=download_request.tasks,
                        n_threads=download_request.n_threads
                    )
                    return_code = download_response['return_code']
                    if return_code != 0:
                        to_update['error_message'] = (
                            f'Return code {return_code} is not 0'
                        )
                        to_update['status'] = 'ERROR'
                    else:
                        to_update['status'] = 'DONE'
                    to_update.update(download_response)
                except Exception as e:
                    to_update['status'] = 'ERROR'
                    to_update['error_message'] = str(e)

                update_kwargs = dynamodb_utils.build_update_item_expression_kwargs(  # noqa:E501
                    to_update)
                dynamodb_client.update_item(
                    TableName=table_name,
                    Key=key,
                    **update_kwargs
                )
        else:
            logger.info('Single invoke event detected')
            if 'tasks' not in event:
                logger.warning('tasks key not found in event')
                logger.warning(event)

            # single event come from trigger request
            download_response = logic.parallel_download_curl_to_s3(
                tasks=event['tasks'])
            return download_response

    except Exception as e:
        logger.exception(str(e))
        raise e