import 'dart:async';

import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:url_launcher/url_launcher.dart';

import '../../core/result.dart';
import '../../domain/entities/payment_card.dart';
import '../../domain/usecase/add_payment_card_usecase.dart';
import '../../domain/usecase/get_payment_cards_usecase.dart';
import '../../domain/usecase/get_profile_usecase.dart';
import '../../domain/usecase/set_main_payment_card_usecase.dart';
import '../event/payment_method_sheet_event.dart';
import '../state/payment_method_sheet_state.dart';

class PaymentMethodSheetBloc
    extends Bloc<PaymentMethodSheetEvent, PaymentMethodSheetState> {
  final GetPaymentCardsUsecase _getPaymentCardsUsecase;
  final GetProfileUseCase _getProfileUseCase;
  final SetMainPaymentCardUsecase _setMainPaymentCardUsecase;
  final AddPaymentCardUsecase _addPaymentCardUsecase;


  PaymentMethodSheetBloc(this._getPaymentCardsUsecase,
      this._setMainPaymentCardUsecase, this._getProfileUseCase,
      this._addPaymentCardUsecase)
      : super(
      PaymentMethodSheetState(status: PaymentMethodSheetStatus.initial)) {
    on<PaymentMethodSheetStarted>(_onStarted);
    on<AddCardButtonPressed>(_onAddCardButtonPressed);
  }

  Future<void> _onStarted(PaymentMethodSheetStarted event,
      Emitter<PaymentMethodSheetState> emit,) async {
    emit(state.copyWith(status: PaymentMethodSheetStatus.loading));

    try {
      final result = await _getPaymentCardsUsecase();
      final profile = await _getProfileUseCase();


      if (result is Success<List<PaymentCard>>) {
        emit(state.copyWith(
          status: PaymentMethodSheetStatus.success,
          balance: profile.balance,
          cards: result.data ?? [],
        ));
      } else {
        emit(state.copyWith(
          status: PaymentMethodSheetStatus.failure,
          errorMessage: 'Failed to load payment cards',
        ));
      }
    } catch (e) {
      emit(state.copyWith(
        status: PaymentMethodSheetStatus.failure,
        errorMessage: e.toString(),
      ));
    }
  }

  Future<void> _onSelectCard(SelectPaymentCardRequested event,
      Emitter<PaymentMethodSheetState> emit,) async {
    // Включаем локальный лоадер на шторке, либо просто ждем ответа
    emit(state.copyWith(status: PaymentMethodSheetStatus.loading));

    final result = await _setMainPaymentCardUsecase(event.card.id);

    if (result is Success<void>) {
      final cardsResult = await _getPaymentCardsUsecase();
      if (cardsResult is Success<List<PaymentCard>>) {
        emit(state.copyWith(
          status: PaymentMethodSheetStatus.success,
          cards: cardsResult.data ?? [],
        ));
      } else {
        emit(state.copyWith(status: PaymentMethodSheetStatus.failure,
            errorMessage: 'Ошибка обновления списка карт'));
      }
    } else {
      emit(state.copyWith(
        status: PaymentMethodSheetStatus.failure,
        errorMessage: 'Не удалось установить карту основной',
      ));
    }
  }

  // Выносим загрузку в отдельный метод для переиспользования
  Future<void> _loadCards(Emitter<PaymentMethodSheetState> emit) async {
    try {
      final result = await _getPaymentCardsUsecase();
      if (result is Success<List<PaymentCard>>) {
        emit(state.copyWith(
          status: PaymentMethodSheetStatus.success,
          cards: result.data ?? [],
        ));
      } else {
        emit(state.copyWith(
          status: PaymentMethodSheetStatus.failure,
          errorMessage: 'Failed to load payment cards',
        ));
      }
    } catch (e) {
      emit(state.copyWith(
        status: PaymentMethodSheetStatus.failure,
        errorMessage: e.toString(),
      ));
    }
  }

  FutureOr<void> _onAddCardButtonPressed(AddCardButtonPressed event,
      Emitter<PaymentMethodSheetState> emit) async {
    try {
      final result = await _addPaymentCardUsecase();

      if (result is Success<Map<String, dynamic>>) {
        final formUrlString = result.data?['formUrl'] as String?;

        if (formUrlString != null && formUrlString.isNotEmpty) {
          final url = Uri.parse(formUrlString);

          if (await canLaunchUrl(url)
          ) {
            launchUrl(
              url,
              mode: LaunchMode.externalApplication,
            );
            emit(state.copyWith(status: PaymentMethodSheetStatus.success));
          } else {
            emit(state.copyWith(
              status: PaymentMethodSheetStatus.failure,
              errorMessage: 'Не удалось открыть ссылку для оплаты',
            ));
          }
        } else {
          emit(state.copyWith(
            status: PaymentMethodSheetStatus.failure,
            errorMessage: 'Ссылка для привязки карты не получена от сервера',
          ));
        }
      } else if (result is Failure) {
        String errorMessage = 'Ошибка при добавлении карты';

        emit(state.copyWith(
          status: PaymentMethodSheetStatus.failure,
          errorMessage: errorMessage,
        ));
      }
    } catch (e) {
      emit(state.copyWith(
        status: PaymentMethodSheetStatus.failure,
        errorMessage: e.toString(),
      ));
    }
  }
}