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.dynamodb import DynamoDBPersistenceLayer, SortKey, TransactKey

from boto3clients import dynamodb_client
from config import ENROLLMENT_TABLE
from enrollment import (
    Course,
    Enrollment,
    Kind,
    LinkedEntity,
    SubscriptionFrozenError,
    User,
    enroll,
)

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:
    new_image = event.detail['new_image']
    # Copy metadata from the failed enrollment for reuse in the new enrollment
    metadata = dyn.collection.get_items(
        TransactKey(new_image['id'])
        + SortKey(
            sk='METADATA#SUBSCRIPTION_COVERED',
            rename_key='subscription',
        )
        + SortKey(
            sk='METADATA#DEDUPLICATION_WINDOW',
            path_spec='offset_days',
            rename_key='dedup_window_offset_days',
        )
        + SortKey(
            sk='ORG',
            rename_key='org',
        ),
        flatten_top=False,
    )
    user = User.model_validate(new_image['user'])
    course = Course.model_validate(new_image['course'])
    subscription = metadata['subscription'] if 'subscription' in metadata else None
    offset_days = metadata.get('dedup_window_offset_days', None)
    enrollment = Enrollment(
        id=uuid4(),
        course=course,
        user=user,
    )

    try:
        enroll(
            enrollment,
            org=metadata.get('org', None),
            subscription=subscription,
            # Reuse the deduplication window if it exists
            deduplication_window={'offset_days': offset_days} if offset_days else None,
            # The enrollment must know its source
            linked_entities=frozenset(
                {
                    LinkedEntity(
                        id=new_image['id'],
                        kind=Kind.ENROLLMENT,
                    ),
                },
            ),
            persistence_layer=dyn,
        )
    except SubscriptionFrozenError:
        pass

    return True