import 'package:equatable/equatable.dart';

import '../data/export_import/seed_label_codec.dart';
import '../data/species_repository.dart';
import '../data/variety_repository.dart';

/// What scanning a QR yielded: not a seed label at all, a variety already in
/// the collection ([varietyId] set), or a seed not held yet ([data] set — the
/// UI asks before adding anything).
class SeedScanResult extends Equatable {
  const SeedScanResult.notALabel() : varietyId = null, data = null;
  const SeedScanResult.match(String this.varietyId) : data = null;
  const SeedScanResult.unknown(SeedLabelData this.data) : varietyId = null;

  final String? varietyId;
  final SeedLabelData? data;

  @override
  List<Object?> get props => [varietyId, data];
}

/// Resolves a scanned QR payload against the collection: decodes the
/// `tane://seed` label and looks the variety up by its label (the identity a
/// keeper printed on the envelope). This is how a physical packet finds its
/// way back to its record — even a re-saved one whose digital thread broke.
Future<SeedScanResult> resolveScannedLabel(
  VarietyRepository repository,
  String raw,
) async {
  final data = SeedLabelCodec.decode(raw);
  if (data == null) return const SeedScanResult.notALabel();
  final varietyId = await repository.findVarietyIdByLabel(data.varietyLabel);
  return varietyId == null
      ? SeedScanResult.unknown(data)
      : SeedScanResult.match(varietyId);
}

/// Adds the scanned seed to the collection — a variety named as the label
/// says, linked to the bundled species when the scientific name matches
/// exactly, with one lot carrying the label's harvest year and origin.
/// Called only after the person confirmed the add prompt.
Future<String> importScannedLabel({
  required VarietyRepository repository,
  required SpeciesRepository species,
  required SeedLabelData data,
}) async {
  final varietyId = await repository.addQuickVariety(label: data.varietyLabel);

  final scientific = data.scientificName?.trim();
  if (scientific != null && scientific.isNotEmpty) {
    final matches = await species.search(scientific, limit: 4);
    for (final m in matches) {
      if (m.scientificName.toLowerCase() == scientific.toLowerCase()) {
        await repository.linkSpecies(varietyId, m.id);
        break;
      }
    }
  }

  await repository.addLot(
    varietyId: varietyId,
    harvestYear: data.year,
    originName: data.origin,
  );
  return varietyId;
}