"""Lambda update-subaccount-mapping function module."""
import csv

import config
from lambdacommon.aws import s3
from lambdacommon.common_config import logger
from src.constants import constants as const
from src.update_subaccount_mapping_in_art_relations import update_mapping_in_art_relations, validate_vendor
from src.update_subaccount_mapping_in_neo4j import update_mapping_in_neo4j


def get_s3_data(bucket, filename):
    """Get file from s3."""
    obj = s3.get_object(bucket, filename)
    data = obj['Body'].read().decode('utf-8').splitlines()
    return data


def handler(event, context):
    """Lambda entry point."""
    logger.info(event)
    if not event.get('filename'):
        logger.error(const.EVENT_ERROR_MESSAGE)
        return {'status': 'Fail'}
    try:
        filename = event.get('filename')

        data = get_s3_data(config.BUCKET, filename)
        reader = csv.DictReader(data)

        subaccount_ids = {}
        if not (const.SUBACCOUNT_ID in
                reader.fieldnames and const.PROJECT_ID in
                reader.fieldnames and const.VENDOR_ID in reader.fieldnames):
            logger.info('Required headers are missing from csv file')
            return {'status': 'Fail'}

        for row in reader:
            if not (row.get(const.SUBACCOUNT_ID) and row.get(const.PROJECT_ID) and row.get(const.VENDOR_ID)):
                subaccount_ids = {}
                logger.info('Data is missing in file')
                break

            subaccount_id = row[const.SUBACCOUNT_ID]
            project_id = int(row[const.PROJECT_ID])
            vendor_id = row[const.VENDOR_ID]

            if not subaccount_ids.get(subaccount_id):
                subaccount_ids[subaccount_id] = [project_id]
            else:
                if project_id not in subaccount_ids.get(subaccount_id):
                    subaccount_ids[subaccount_id].append(project_id)

        if not subaccount_ids:
            return {'status': 'Fail'}

        result = validate_vendor(subaccount_ids, vendor_id, logger)

        if not result:
            return {'status': 'Fail'}

        update_mapping_in_art_relations(subaccount_ids, logger)

        update_mapping_in_neo4j(vendor_id, logger)

        return {'status': 'OK'}

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