from datetime import timedelta

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, ttl
from layercake.dynamodb import DynamoDBPersistenceLayer

from boto3clients import dynamodb_client
from config import (
    ENROLLMENT_TABLE,
)

logger = Logger(__name__)
enrollment_layer = 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']
    enrollment_id = new_image['id']
    user = new_image['user']
    course = new_image['course']
    now_ = now()

    with enrollment_layer.transact_writer() as transact:
        transact.put(
            item={
                'id': enrollment_id,
                'sk': 'SCHEDULE#REMINDER_NO_ACCESS_AFTER_3_DAYS',
                'name': user.name,
                'email': user.email,
                'course': course.name,
                'created_at': now_,
                'ttl': ttl(days=3, start_dt=now_),
            },
        )
        # By default, the enrollment will expire when the access period ends
        # (scheduled below).
        # If the enrollment is completed earlier (e.g., certificate issued),
        # the expiration schedule is canceled and an archive schedule
        # (`SCHEDULE#SET_AS_ARCHIVED`) is created instead.
        transact.put(
            item={
                'id': enrollment_id,
                'sk': 'SCHEDULE#SET_AS_EXPIRED',
                'name': user.name,
                'email': user.email,
                'course': course.name,
                'created_at': now_,
                'ttl': ttl(start_dt=now_ + timedelta(days=course.access_period)),
            },
        )
        transact.put(
            item={
                'id': enrollment_id,
                'sk': 'REMINDER_ACCESS_PERIOD_BEFORE_15_DAYS',
                'name': user.name,
                'email': user.email,
                'course': course.name,
                'created_at': now_,
                'ttl': ttl(start_dt=now_ + timedelta(days=course.access_period - 15)),
            },
        )

    return True