from uuid import uuid4

from aws_lambda_powertools import Logger
from aws_lambda_powertools.utilities.data_classes import (
    EventBridgeEvent,
    event_source,
)
from aws_lambda_powertools.utilities.typing import LambdaContext
from layercake.dateutils import now
from layercake.dynamodb import DynamoDBPersistenceLayer, KeyPair

from boto3clients import dynamodb_client
from config import ENROLLMENT_TABLE, ORDER_TABLE

logger = Logger(__name__)
dyn = DynamoDBPersistenceLayer(ENROLLMENT_TABLE, dynamodb_client)


@event_source(data_class=EventBridgeEvent)
@logger.inject_lambda_context
def lambda_handler(event: EventBridgeEvent, context: LambdaContext) -> bool:
    old_image = event.detail['old_image']
    order_id = old_image['seat']['order_id']
    enrollment_id = old_image['enrollment_id']
    *_, org_id = old_image['id'].split('#')
    now_ = now()

    with dyn.transact_writer() as transact:
        transact.update(
            key=KeyPair(
                pk=order_id,
                sk=f'ENROLLMENT#{enrollment_id}',
                table_name=ORDER_TABLE,
            ),
            cond_expr='attribute_exists(sk) AND #status = :scheduled',
            update_expr='SET #status = :rollback, \
                             rollback_at = :now, \
                             reason = :reason',
            expr_attr_names={
                '#status': 'status',
            },
            expr_attr_values={
                ':rollback': 'ROLLBACK',
                ':scheduled': 'SCHEDULED',
                ':reason': 'CANCELLATION',
                ':now': now_,
            },
            table_name=ORDER_TABLE,
        )
        transact.put(
            item={
                'id': f'SEAT#ORG#{org_id}',
                'sk': f'ORDER#{order_id}#ENROLLMENT#{uuid4()}',
                'course': old_image['course'],
                'created_at': now_,
            }
        )

    return True