import json
import sys

from django.core.management.base import BaseCommand, CommandError
from django.db import transaction

from events.models import Event
from games.services.planning import import_planning


class Command(BaseCommand):
    help = (
        "Import an event planning from the legacy PolyLAN planning JSON "
        "(slots missing from the file are deleted)"
    )

    def add_arguments(self, parser):
        parser.add_argument("event_path", help="Path of the event, e.g. polylan-43")
        parser.add_argument("json_file", help="Planning JSON file, '-' for stdin")

    def handle(self, *args, **options):
        try:
            event = Event.objects.get(path=options["event_path"])
        except Event.DoesNotExist:
            raise CommandError(f"No event with path {options['event_path']!r}")

        if options["json_file"] == "-":
            data = json.load(sys.stdin)
        else:
            with open(options["json_file"], encoding="utf-8") as f:
                data = json.load(f)

        entries = data["list"] if isinstance(data, dict) else data
        with transaction.atomic():
            created, updated, deleted = import_planning(event, entries)

        self.stdout.write(
            self.style.SUCCESS(
                f"Planning of {event}: {created} created, {updated} updated, {deleted} deleted"
            )
        )