import 'package:flutter/foundation.dart';

import 'models.dart';
import 'service.dart';

class DestinationSelectionProvider extends ChangeNotifier {
  DestinationSelectionProvider(this.service, this.context);
  final DestinationService service;
  final PayoutContext context;
  final assessments = <String, PayoutEligibility>{};
  bool busy = false, _disposed = false;
  DestinationIssue? error;
  Future<void> assess(List<SavedDestination> methods) async {
    for (final d in methods) {
      try {
        final assessment = await service.assess(d.input, context);
        if (_disposed) return;
        assessments[d.id] = assessment;
      } on DestinationException catch (e) {
        if (_disposed) return;
        assessments[d.id] = PayoutEligibility(
          EligibilityState.requiresAction,
          reason: e.issue,
        );
      } catch (_) {
        if (_disposed) return;
        assessments[d.id] = const PayoutEligibility(
          EligibilityState.temporarilyUnavailable,
          reason: DestinationIssue.unavailable,
        );
      }
    }
    if (!_disposed) notifyListeners();
  }

  Future<SavedReference?> select(SavedDestination d) async {
    if (busy) return null;
    busy = true;
    error = null;
    notifyListeners();
    SavedReference? result;
    try {
      final current = await service.get(d.id);
      final a = await service.assess(current.input, context);
      if (_disposed) return null;
      assessments[d.id] = a;
      if (a.eligible) result = current.input;
    } on DestinationException catch (e) {
      error = e.issue;
    } catch (_) {
      error = DestinationIssue.unavailable;
    }
    if (_disposed) return null;
    busy = false;
    notifyListeners();
    return result;
  }

  @override
  void dispose() {
    _disposed = true;
    super.dispose();
  }
}