from django.contrib.auth import get_user_model
from django.core.management.base import BaseCommand, CommandError
from django.db.models import Q

from apps.library import e621, matching
from apps.library.models import MatchTask, MediaItem


class Command(BaseCommand):
    help = (
        "Match library items against e621 by MD5 and refresh matched metadata "
        "(also detects deleted posts). Uses a user's stored e621 credentials."
    )

    def add_arguments(self, parser):
        parser.add_argument(
            "--user",
            help="Username whose e621 credentials to use "
            "(defaults to the first staff account with credentials).",
        )
        parser.add_argument(
            "--scope",
            choices=[MatchTask.SCOPE_MISSING, MatchTask.SCOPE_ALL],
            default=MatchTask.SCOPE_MISSING,
            help="'missing' checks unchecked items only; 'all' also refreshes "
            "already matched items (default: missing).",
        )

    def handle(self, *args, **options):
        User = get_user_model()
        username = options.get("user")
        if username:
            user = User.objects.filter(username=username).first()
            if user is None:
                raise CommandError(f"No such user: {username}")
        else:
            user = (
                User.objects.filter(
                    Q(is_superuser=True)
                    | Q(is_staff=True)
                    | Q(role=User.ROLE_STAFF),
                    e621_api_key__gt="",
                    e621_username__gt="",
                )
                .order_by("id")
                .first()
            )
        if not e621.credentials_configured(user):
            raise CommandError(
                "No e621 credentials found. Pass --user or configure them in Account."
            )

        queryset = matching.scope_queryset(options["scope"])
        total = queryset.count()
        counters = {"matched": 0, "not_found": 0, "deleted": 0}
        for index, item_id in enumerate(queryset.values_list("id", flat=True), start=1):
            item = MediaItem.objects.filter(id=item_id).first()
            if item is None:
                continue
            try:
                status = matching.check_item(item, user)
            except e621.E621Error as exc:
                raise CommandError(f"Aborted after {index - 1}/{total}: {exc}")
            counters[status] = counters.get(status, 0) + 1
            self.stdout.write(
                f"[{index}/{total}] J-{item_id}: {status}", ending="\r"
            )

        self.stdout.write(
            self.style.SUCCESS(
                "\nDone: "
                f"{counters['matched']} matched, {counters['not_found']} not found, "
                f"{counters['deleted']} deleted (scope: {options['scope']})."
            )
        )