from __future__ import annotations

from django.core.management.base import BaseCommand, CommandError
from django.utils.dateparse import parse_date

from apps.ingestion.extractors import ExtractorError, available_extractors, create_extractor


class Command(BaseCommand):
    help = "Run a snapshot extractor and emit importable JSON snapshots."

    def add_arguments(self, parser):
        parser.add_argument("extractor_name", choices=available_extractors())
        parser.add_argument(
            "--output-path",
            dest="output_path",
            default=None,
            help="Directory or .json file path where snapshot should be written. Defaults to incoming dir.",
        )
        parser.add_argument(
            "--snapshot-date",
            dest="snapshot_date",
            default=None,
            help="Override snapshot date in YYYY-MM-DD format.",
        )
        parser.add_argument(
            "--dry-run",
            action="store_true",
            help="Validate extraction/normalization without writing snapshot file.",
        )
        parser.add_argument(
            "--indent",
            type=int,
            default=2,
            help="JSON indent level for emitted snapshots.",
        )

    def handle(self, *args, **options):
        snapshot_date = None
        if options["snapshot_date"]:
            snapshot_date = parse_date(options["snapshot_date"])
            if snapshot_date is None:
                raise CommandError("--snapshot-date must be YYYY-MM-DD.")

        try:
            extractor = create_extractor(options["extractor_name"])
            result = extractor.run(
                output_path=options["output_path"],
                snapshot_date=snapshot_date,
                write_output=not options["dry_run"],
                indent=options["indent"],
            )
        except ExtractorError as exc:
            raise CommandError(str(exc)) from exc

        output_path = str(result.output_path) if result.output_path else "<dry-run>"
        self.stdout.write(
            self.style.SUCCESS(
                f"Extractor {result.extractor_name} completed: "
                f"source={result.source_name} date={result.snapshot_date} "
                f"records={result.records_count} output={output_path}"
            )
        )