rfac: error handling in profile bloc

Author: aman-singh7

lib/domain/repositories/user_repository.dart

@@ -2,6 +2,7 @@ import 'dart:convert';
 import 'dart:io';
 
 import '../../data/config/config.dart';
+import '../../data/constants/strings.dart';
 import '../../data/services/local/storage_service.dart';
 import '../../data/services/remote/api_service.dart';
 import '../../utils/auth_token.dart' as auth_token_utils;
@@ -196,7 +197,8 @@ class UserRepository {
         response['data'].map((e) => Following.fromJson(e)),
       );
     }
-    return null;
+
+    throw Exception(AppStrings.genericError);
   }
 
   static Future<bool> verifyHandle(String site, String handle) async {
@@ -225,6 +227,7 @@ class UserRepository {
         _users.add(User.fromJson(user));
       }
     }
+
     return _users;
   }
 
@@ -261,7 +264,8 @@ class UserRepository {
     if (response['status_code'] == 200) {
       return SubmissionStatus.fromJson(response['data']);
     }
-    return null;
+
+    throw Exception(AppStrings.genericError);
   }
 
   static Future<List<ActivityDetails>?> getActivityDetails(String id) async {
@@ -279,7 +283,8 @@ class UserRepository {
         response['data'].map((e) => ActivityDetails.fromJson(e)),
       );
     }
-    return null;
+
+    throw Exception(AppStrings.genericError);
   }
 
   static Future<int> updatePassword(

lib/presentation/profile/bloc/profile_bloc.dart

@@ -9,6 +9,7 @@ import '../../../data/constants/strings.dart';
 import '../../../data/services/local/storage_service.dart';
 import '../../../domain/models/activity_details.dart';
 import '../../../domain/models/following.dart';
+import '../../../domain/models/status.dart';
 import '../../../domain/models/submission_status.dart';
 import '../../../domain/models/user.dart';
 import '../../../domain/repositories/user_repository.dart';
@@ -26,7 +27,9 @@ class ProfileBloc extends Bloc<ProfileEvent, ProfileState> {
   }
 
   void _onFetchDetails(FetchDetails event, Emitter<ProfileState> emit) async {
-    if (!state.isLoading) emit(state.copyWith(isLoading: true));
+    if (state.status is! Loading) {
+      emit(state.copyWith(status: const Status.loading()));
+    }
 
     // Fetch user details
     if (event.userId.isEmpty) {
@@ -35,12 +38,19 @@ class ProfileBloc extends Bloc<ProfileEvent, ProfileState> {
       _user = await UserRepository.fetchUserDetails(uid: event.userId);
     }
 
-    _followingList = await UserRepository.getFollowingList();
+    SubmissionStatus? _subStats;
+    List<ActivityDetails>? _activityDetails;
+    // TODO(aman-singh7): Throw specific Error
+    try {
+      _followingList = await UserRepository.getFollowingList();
 
-    final _subStats = await UserRepository.getSubmissionStatusData(_user!.id!);
+      _subStats = await UserRepository.getSubmissionStatusData(_user!.id!);
 
-    final _activityDetails =
-        await UserRepository.getActivityDetails(_user!.id!);
+      _activityDetails = await UserRepository.getActivityDetails(_user!.id!);
+    } on Exception catch (_) {
+      emit(state.copyWith(status: const Status.error(AppStrings.genericError)));
+      return;
+    }
 
     for (final activity in _activityDetails ?? <ActivityDetails>[]) {
       if (activity.createdAt == null) continue;
@@ -58,7 +68,7 @@ class ProfileBloc extends Bloc<ProfileEvent, ProfileState> {
     _isFollowing ??= false;
 
     emit(state.copyWith(
-      isLoading: false,
+      status: const Status(),
       user: _user,
       following: _followingList,
       submissionStatus: _subStats,

lib/presentation/profile/bloc/profile_state.dart

@@ -3,7 +3,7 @@ part of 'profile_bloc.dart';
 @freezed
 class ProfileState with _$ProfileState {
   const factory ProfileState({
-    @Default(true) bool isLoading,
+    @Default(Status.loading()) Status status,
     @Default(true) bool personalProfile,
     @Default(false) bool isFollowing,
     @Default(false) bool showFollowing,

lib/presentation/profile/profile_screen.dart

@@ -2,7 +2,10 @@ import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 
+import '../../data/constants/strings.dart';
 import '../../data/constants/styles.dart';
+import '../../domain/models/status.dart';
+import '../../utils/snackbar.dart';
 import 'bloc/profile_bloc.dart';
 import 'widgets/acceptance_graph.dart';
 import 'widgets/accuracy_display.dart';
@@ -19,13 +22,22 @@ class ProfileScreen extends StatelessWidget {
   Widget build(BuildContext context) {
     return BlocProvider(
       create: (context) => ProfileBloc()..add(const FetchDetails()),
-      child: BlocBuilder<ProfileBloc, ProfileState>(
+      child: BlocConsumer<ProfileBloc, ProfileState>(
+        listenWhen: (previous, current) =>
+            previous.status.hashCode != current.status.hashCode,
+        listener: (context, state) {
+          if (state.status is Error) {
+            showSnackBar(message: AppStrings.genericError);
+          }
+        },
         // When Loading state changes
         buildWhen: (previous, current) =>
-            previous.isLoading ^ current.isLoading ||
+            previous.status.hashCode != current.status.hashCode ||
             previous.showFollowing ^ current.showFollowing,
         builder: (context, state) {
-          if (state.isLoading) return const ProfileLoadingState();
+          if (state.status is Loading || state.status is Error) {
+            return const ProfileLoadingState();
+          }
 
           if (state.showFollowing) return const FollowingView();