import os
from celery import Celery
from celery.schedules import crontab
from django.conf import settings

os.environ.setdefault("DJANGO_SETTINGS_MODULE", "config.settings.development")

app = Celery("hoopscout")
app.config_from_object("django.conf:settings", namespace="CELERY")
app.autodiscover_tasks()


def _parse_cron_expression(expression: str) -> dict[str, str]:
    parts = expression.split()
    if len(parts) != 5:
        raise ValueError(
            "INGESTION_SCHEDULE_CRON must have 5 fields: minute hour day_of_month month_of_year day_of_week."
        )
    return {
        "minute": parts[0],
        "hour": parts[1],
        "day_of_month": parts[2],
        "month_of_year": parts[3],
        "day_of_week": parts[4],
    }


def build_periodic_schedule() -> dict:
    if not settings.INGESTION_SCHEDULE_ENABLED:
        return {}

    schedule_kwargs = _parse_cron_expression(settings.INGESTION_SCHEDULE_CRON)
    return {
        "ingestion.scheduled_provider_sync": {
            "task": "apps.ingestion.tasks.scheduled_provider_sync",
            "schedule": crontab(**schedule_kwargs),
        }
    }


app.conf.beat_schedule = build_periodic_schedule()