from argparse import ArgumentParser
from typing import Any

from django.conf import settings
from django.core.management.base import CommandError
from typing_extensions import override

from zerver.actions.realm_settings import do_delete_all_realm_attachments
from zerver.lib.management import ZulipBaseCommand
from zerver.models import Message, UserProfile


class Command(ZulipBaseCommand):
    help = """Script to permanently delete a realm. Recommended only for removing
realms used for testing; consider using deactivate_realm instead."""

    @override
    def add_arguments(self, parser: ArgumentParser) -> None:
        self.add_realm_args(parser, required=True)

    @override
    def handle(self, *args: Any, **options: str) -> None:
        realm = self.get_realm(options)
        assert realm is not None  # Should be ensured by parser

        user_count = UserProfile.objects.filter(
            realm_id=realm.id,
            is_active=True,
            is_bot=False,
        ).count()

        message_count = Message.objects.filter(realm=realm).count()

        print(f"This realm has {user_count} users and {message_count} messages.\n")

        if settings.BILLING_ENABLED:
            # Deleting a Realm object also deletes associating billing
            # metadata in an invariant-violating way, so we should
            # never use this tool for a realm with billing set up.
            from corporate.models import CustomerPlan, get_customer_by_realm

            customer = get_customer_by_realm(realm)
            if customer and (
                customer.stripe_customer_id
                or CustomerPlan.objects.filter(customer=customer).exists()
            ):
                raise CommandError("This realm has had a billing relationship associated with it!")

        print(
            "This command will \033[91mPERMANENTLY DELETE\033[0m all data for this realm.  "
            "Most use cases will be better served by scrub_realm and/or deactivate_realm."
        )

        confirmation = input("Type the name of the realm to confirm: ")
        if confirmation != realm.string_id:
            raise CommandError("Aborting!")

        # Explicitly remove the attachments and their files in backend
        # storage; failing to do this leaves dangling files
        do_delete_all_realm_attachments(realm)

        # TODO: This approach leaks Recipient and Huddle objects,
        # because those don't have a foreign key to the Realm or any
        # other model it cascades to (Realm/Stream/UserProfile/etc.).
        realm.delete()

        print("Realm has been successfully permanently deleted.")