Mobile App

The mobile application is built with Flutter and targets iOS, Android, and Web. It is the primary interface for alumni to browse events, manage their profiles, and interact with the platform.

Tech Stack

Category	Technology	Version
Language	Dart	^3.8+
Framework	Flutter	^3.32+
State Management	flutter_bloc (Cubit)	^9.0+
Navigation	AutoRoute	^9.3+
HTTP Client	Dio	^5.8+
Serialization	Freezed + json_serializable	^2.5, ^6.9
Error Handling	fpdart (functional)	^1.1+
Secure Storage	flutter_secure_storage	^9.2+
Local Database	sqflite (mobile)	^2.4+
Maps	flutter_map	latest
SVG Support	flutter_svg	latest
Analytics	AppMetrica	native
Code Generation	build_runner + freezed_runner	latest
Logging	logger	^2.5+

3-Layer Architecture

Project Structure

lib/
├── main.dart                     # Entry point, system UI config
├── app.dart                      # MultiBlocProvider DI, MaterialApp, AutoRoute
├── data/
│   ├── gateways/                 # HTTP interfaces + Dio implementations
│   │   ├── auth_gateway.dart / _impl.dart
│   │   ├── events_gateway.dart / _impl.dart
│   │   ├── profile_gateway.dart / _impl.dart
│   │   ├── users_gateway.dart / _impl.dart
│   │   └── locations_gateway.dart / _impl.dart
│   ├── models/                   # JSON-mapped Freezed data models
│   ├── token/                    # TokenManager + secure storage persistence
│   ├── config/                   # API base URL config (web vs mobile)
│   ├── paths.dart                # API endpoint string constants
│   ├── secrets/                  # AppMetrica key loader
│   └── db/                      # sqflite DB manager
├── application/
│   ├── repositories/             # Business logic interfaces + implementations
│   │   ├── auth/
│   │   ├── events/               # With in-memory caching
│   │   ├── users/
│   │   ├── locations/
│   │   └── reporter/             # AppMetrica / Mock analytics
│   ├── models/                   # Domain models (Freezed)
│   │   ├── profile.dart
│   │   ├── event.dart
│   │   ├── cost.dart
│   │   └── ...
│   └── mappers/                  # DataModel → DomainModel converters
├── presentation/
│   ├── router/                   # AutoRoute config + generated routes
│   ├── blocs/                    # Cubits (one per feature)
│   ├── pages/                    # Screen widgets
│   ├── managers/                 # app_loading_manager.dart (startup orchestration)
│   └── common/
│       ├── constants/            # AppColors, AppTextStyles
│       └── widgets/              # Shared reusable widgets
└── util/
    └── logger.dart

State Management: Cubit Pattern

Cubits are the lighter variant of BLoC — they emit states directly via functions instead of processing events.

Generic LoadedState

All Cubits use a sealed LoadedState<T> class:

LoadedState<T>
├── LoadedStateInit()        — initial/idle
├── LoadedStateLoading()     — async operation in progress
├── LoadedStateData(T data)  — success with typed payload
└── LoadedStateError(String) — failure with message

Cubit Inventory

Cubit	Scope	Responsibility
AuthCubit	Auth pages	Email/password login, validation
RegistrationCubit	Registration page	Registration form + API call
EventsListCubit	Global (root)	Load + cache event list
ProfileCubit	Global (root)	Load current user profile + participation
ProfileEditingCubit	Edit profile page	Update bio, photo, social links
OneEventCubit	Event detail page	Fetch event, join/leave
RootPageCubit	Root page	Bottom navigation tab index
PinLocationsCubit	Map page	Load event pins for map
PasswordReset*Cubits	Password reset pages	Request + confirm reset flow

Navigation (AutoRoute)

Dependency Injection

Dependencies are wired at app startup in app.dart using Flutter's MultiBlocProvider:

Services are accessed via context.read<T>() throughout the widget tree.

Data Flow: Load Events

Error Handling Strategy

The app uses fpdart Either<L, R> types in the repository layer:

• Right<EventModel> — success path
• Left<AppError> — typed error (network failure, auth error, not found, etc.)

Cubits pattern-match on Either to emit LoadedStateData or LoadedStateError.

Analytics

The analytics reporter is abstracted behind an interface:

Implementation	When Used
ReporterAppMetrica	Production builds (uses AppMetrica SDK)
ReporterMock	Testing / development (no-op)

Platform Notes

Platform	Config Source	Token Storage
Android / iOS	App environment	flutter_secure_storage (Keychain/Keystore)
Web	window.apiBaseUrl injected at build time	Browser secure storage