import 'package:bloc/bloc.dart';
import 'package:dartz/dartz.dart';
import 'package:freezed_annotation/freezed_annotation.dart';
import 'package:injectable/injectable.dart';

import '../../../domain/wallet/wallet.dart';

part 'voucher_loader_event.dart';
part 'voucher_loader_state.dart';
part 'voucher_loader_bloc.freezed.dart';

/// Katalog voucher yang bisa ditukar (§9.1).
@injectable
class VoucherLoaderBloc extends Bloc<VoucherLoaderEvent, VoucherLoaderState> {
  final IVoucherRepository _repository;

  VoucherLoaderBloc(this._repository) : super(VoucherLoaderState.initial()) {
    on<VoucherLoaderEvent>(_onVoucherLoaderEvent);
  }

  Future<void> _onVoucherLoaderEvent(
    VoucherLoaderEvent event,
    Emitter<VoucherLoaderState> emit,
  ) {
    return event.map(
      fetched: (e) async {
        emit(state.copyWith(isFetching: true, failureOption: none()));

        final result = await _repository.getVouchers();

        final data = result.fold(
          (f) => state.copyWith(failureOption: optionOf(f)),
          (vouchers) => state.copyWith(vouchers: vouchers, hasLoaded: true),
        );

        emit(data.copyWith(isFetching: false));
      },
    );
  }
}