from http import HTTPStatus
from typing import Annotated

from aws_lambda_powertools import Logger
from aws_lambda_powertools.event_handler.api_gateway import Router
from aws_lambda_powertools.event_handler.exceptions import NotFoundError
from aws_lambda_powertools.event_handler.openapi.params import Body, Query
from layercake.dynamodb import DynamoDBPersistenceLayer, KeyPair, PartitionKey
from pydantic import FutureDatetime

from api_gateway import JSONResponse
from boto3clients import dynamodb_client
from config import ENROLLMENT_TABLE

from ...enrollments.enroll import Enrollment, Org, Subscription, enroll_now

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


class ScheduledNotFoundError(NotFoundError): ...


@router.get('/<org_id>/enrollments/scheduled')
def scheduled(
    org_id: str,
    start_key: Annotated[str | None, Query] = None,
):
    return dyn.collection.query(
        key=PartitionKey(f'SCHEDULED#ORG#{org_id}'),
        start_key=start_key,
        limit=150,
    )


@router.delete('/<org_id>/enrollments/scheduled')
def cancel(
    org_id: str,
    scheduled_for: Annotated[FutureDatetime, Body(embed=True)],
    lock_hash: Annotated[str, Body(embed=True)],
):
    with dyn.transact_writer() as transact:
        transact.delete(
            key=KeyPair(
                pk=f'SCHEDULED#ORG#{org_id}',
                sk=f'{scheduled_for.isoformat()}#{lock_hash}',
            ),
            cond_expr='attribute_exists(sk)',
            exc_cls=ScheduledNotFoundError,
        )
        transact.delete(
            key=KeyPair(
                pk='LOCK#SCHEDULED',
                sk=lock_hash,
            ),
        )

    return JSONResponse(status_code=HTTPStatus.NO_CONTENT)


@router.post('/<org_id>/enrollments/scheduled/proceed')
def proceed(
    org_id: str,
    scheduled_for: Annotated[FutureDatetime, Body(embed=True)],
    lock_hash: Annotated[str, Body(embed=True)],
):
    pk = f'SCHEDULED#ORG#{org_id}'
    sk = f'{scheduled_for.isoformat()}#{lock_hash}'

    scheduled = dyn.collection.get_item(
        KeyPair(pk, sk),
        exc_cls=ScheduledNotFoundError,
    )
    org = Org(
        id=org_id,
        name=scheduled['org_name'],
    )
    subscription = Subscription(
        billing_day=scheduled['subscription_billing_day'],
    )

    try:
        enrollment = enroll_now(
            Enrollment(
                user=scheduled['user'],
                course=scheduled['course'],
            ),
            {
                'org': org,
                'subscription': subscription,
                'created_by': router.context['user'],
            },
        )

        with dyn.transact_writer() as transact:
            transact.delete(key=KeyPair(pk, sk))
            transact.delete(key=KeyPair('LOCK#SCHEDULED', lock_hash))
    except Exception:
        raise
    else:
        return JSONResponse(
            status_code=HTTPStatus.CREATED,
            body=enrollment,
        )