import json
import logging
import os
from dataclasses import dataclass

import boto3
from aws_lambda_powertools import Tracer

from common.response import no_content
from libs.utils import response_error

tracer = Tracer()
logger = logging.getLogger(__name__)
logger.setLevel(os.environ.get('LOG_LEVEL') or logging.ERROR)

dynamodb = boto3.resource('dynamodb')
dataset_info_table = dynamodb.Table(os.environ.get('DATASET_INFO_TABLE'))
dataset_item_table = dynamodb.Table(os.environ.get('DATASET_ITEM_TABLE'))

s3_bucket_name = os.environ.get('S3_BUCKET_NAME')
s3 = boto3.resource('s3')
bucket = s3.Bucket(s3_bucket_name)


@dataclass
class DeleteDatasetsEvent:
    dataset_name_list: [str]


@tracer.capture_lambda_handler
def handler(event, ctx):
    try:
        logger.info(json.dumps(event))
        body = DeleteDatasetsEvent(**json.loads(event['body']))

        # todo will be removed
        # permissions_check(event, [PERMISSION_TRAIN_ALL])

        # unique list for preventing duplicate delete
        dataset_name_list = list(set(body.dataset_name_list))

        for dataset_name in dataset_name_list:

            # get dataset items
            files = dataset_item_table.query(
                KeyConditionExpression='dataset_name = :dataset_name',
                ExpressionAttributeValues={
                    ':dataset_name': dataset_name
                }
            )

            if 'Items' in files:
                logger.info(f"files: {files['Items']}")
                for file in files['Items']:
                    dataset_item_table.delete_item(
                        Key={
                            'dataset_name': dataset_name,
                            'sort_key': file['sort_key']
                        }
                    )

            prefix = f"dataset/{dataset_name}/"
            logger.info(f'delete prefix: {prefix}')

            response = bucket.objects.filter(Prefix=prefix).delete()
            logger.info(f'delete response: {response}')

            dataset_info_table.delete_item(Key={'dataset_name': dataset_name})

        return no_content(message='datasets deleted')
    except Exception as e:
        return response_error(e)