import '../entities/customer.dart';
import '../entities/transaction.dart';

abstract class TransactionRepository {
  /// Persists a completed sale as one atomic unit.
  ///
  /// The bill, the stock it consumed and the shopper's loyalty movement either
  /// all land or none do, so a failure part-way through can never leave a
  /// persisted bill that the cashier believes failed.
  Future<void> commitSale({
    required SaleTransaction transaction,
    required Map<String, double> stockMovements,
    Customer? updatedCustomer,
  });

  /// Reverses a sale still inside its cancellation window: deletes the order,
  /// restores the stock it consumed, and puts an attached shopper's loyalty
  /// balance back to what it was immediately before the sale.
  ///
  /// Only valid before the bill has been offered to the back office — this
  /// does not send a cancellation anywhere, it erases the sale as if it had
  /// never happened locally.
  Future<void> voidSale({
    required SaleTransaction transaction,
    required Map<String, double> stockMovements,
  });

  Future<List<SaleTransaction>> history({int limit = 50});

  Future<SaleTransaction?> findByInvoice(String invoiceNumber);

  /// Next invoice sequence for the current month.
  Future<int> nextInvoiceSequence();

  Future<void> park(ParkedBill bill);

  Future<List<ParkedBill>> parkedBills();

  Future<void> removeParked(String id);

  Future<double> salesTotalForDay(DateTime day);
}