import 'package:drift/drift.dart';

import '../models/remote_command.dart';
import 'app_database.dart';

/// The product catalog as the website manages it.
extension CatalogQueries on AppDatabase {
  /// Makes the local products match [catalog]: new products are added,
  /// changed ones updated, archived ones and products the server doesn't
  /// know (such as the default products of a new tablet) are hidden. Hidden,
  /// not deleted: open tabs and the history refer to them.
  ///
  /// The stock is not touched here: the stock rebase that follows sets it, a
  /// new product starts as untracked until then. Local images are kept.
  Future<void> applyServerCatalog(List<ServerProduct> catalog) {
    return transaction(() async {
      final local = {
        for (final row in await select(products).get()) row.id: row,
      };

      for (final product in catalog) {
        final category = product.category ?? '';
        final lowStockThreshold = product.lowStockThreshold ?? 0;
        final existing = local.remove(product.id);

        if (existing == null) {
          await into(products).insert(
            ProductsCompanion.insert(
              id: product.id,
              name: product.name,
              category: category,
              stockQuantity: 0,
              lowStockThreshold: lowStockThreshold,
              infiniteStock: const Value(true),
              priceInCents: product.priceInCents,
              active: Value(!product.archived),
            ),
          );
          continue;
        }

        if (existing.name == product.name &&
            existing.category == category &&
            existing.priceInCents == product.priceInCents &&
            existing.lowStockThreshold == lowStockThreshold &&
            existing.active == !product.archived) {
          continue;
        }
        await (update(
          products,
        )..where((row) => row.id.equals(product.id))).write(
          ProductsCompanion(
            name: Value(product.name),
            category: Value(category),
            priceInCents: Value(product.priceInCents),
            lowStockThreshold: Value(lowStockThreshold),
            active: Value(!product.archived),
          ),
        );
      }

      final unknown = [
        for (final row in local.values)
          if (row.active) row.id,
      ];
      if (unknown.isNotEmpty) {
        await (update(products)..where((row) => row.id.isIn(unknown))).write(
          const ProductsCompanion(active: Value(false)),
        );
      }
    });
  }
}