presentation.md

Presentation Layer

Purpose

The presentation layer contains everything the user sees and interacts with: Flutter widgets, routing, and Bloc-based state management.

It depends on:

• The application layer — to invoke use cases.
• The domain layer — to read entities and handle domain errors.

It must not depend on the infrastructure layer directly.

Rules

• Blocs may only depend on use cases (not repository interfaces).
• No raw HTTP calls, JSON parsing, or direct data source access.
• All state changes go through Bloc events.
• Widget trees reflect state — they never drive logic.

Components

Component	Description
Page	StatelessWidget that provides Blocs to the tree. Entry point for a feature.
View	StatelessWidget that reads from Blocs and delegates to the Body.
Body	StatelessWidget (or StatefulWidget) that renders the actual UI.
Bloc	State management; receives events, emits states.
Events	Immutable actions that trigger Bloc state transitions.
States	Immutable snapshots of the Bloc's current state.

Feature Organization

Each feature (screen or flow) is self-contained in its own folder under presentation/:

presentation/
└── login/
    ├── bloc/
    │   ├── login_bloc.dart
    │   ├── login_event.dart
    │   ├── login_state.dart
    │   └── bloc.dart           # barrel
    ├── view/
    │   └── login_page.dart     # Page + View in the same file
    └── widgets/
        ├── login_body.dart
        ├── email_input.dart
        └── widgets.dart        # barrel

Detailed Docs

• Features — feature structure and naming
• Pages — the Page widget
• Views — the View widget
• Bodies — the Body widget
• Blocs — Bloc class rules
• Events — Event class rules
• States — State class rules