Define ActivityRegistrationCubit states and events
epic-quick-activity-registration-business-logic-task-007 — Define the sealed class hierarchy for ActivityRegistrationCubit states: ActivityRegistrationInitial, ActivityRegistrationStep (with currentStep enum and per-field value slices), ActivityRegistrationSubmitting, ActivityRegistrationSuccess (containing the optimistic ActivityRecord), and ActivityRegistrationFailure (with user-friendly error message). Use freezed or manual sealed classes consistent with the rest of the codebase.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 1 - 540 tasks
Can start after Tier 0 completes
Implementation Notes
Check the existing BLoC files in the codebase to determine whether the project uses freezed or manual sealed classes — match that pattern exactly. If freezed is used, annotate the union with @freezed and run build_runner. If manual sealed classes are used (Dart 3 sealed keyword), write each subclass as a final class extending the sealed base. The RegistrationStep enum's next()/previous() methods can be implemented as extension methods on the enum rather than methods on the enum itself if that is the codebase convention.
Keep all state definitions in lib/features/activity_registration/presentation/cubit/activity_registration_state.dart. Do not put business logic in state classes — states are pure data containers.
Testing Requirements
Unit tests with flutter_test. Test: (1) each state class can be instantiated with required fields, (2) ActivityRegistrationStep.copyWith correctly updates individual fields while preserving others, (3) equality — two ActivityRegistrationStep instances with identical fields are equal, (4) RegistrationStep.next() returns correct next step and null at last step, (5) RegistrationStep.previous() returns correct previous step and null at first step, (6) ActivityRegistrationFailure.userFacingMessage is set correctly from constructor. No widget tests required for this task.
The wizard Cubit manages multiple concurrent state slices (current step, each field value, submission status, error state). As the number of wizard steps grows, the state class can become unwieldy, making it difficult to reason about transitions, leading to subtle bugs where advancing a step resets a previously filled field.
Mitigation & Contingency
Mitigation: Use an immutable state model (copyWith pattern) with a separate sealed class per wizard step state. Keep the Cubit's emit calls minimal and always derive the next state from the current state to prevent accidental field resets. Document the state machine transitions explicitly in code comments.
Contingency: If state complexity becomes unmanageable, split into a parent WizardCubit (owns step navigation and submission) and per-step child Cubits (own individual field state), coordinating via a shared repository layer.
Organisation-specific compensation eligibility rules (e.g., activity type + duration thresholds) are business logic that may change independently of the app release cycle. Hardcoding these rules in ActivityRegistrationService means rule changes require a new app deployment, causing delays and potential financial errors if the deployed version uses outdated rules.
Mitigation & Contingency
Mitigation: Model compensation rules as configuration fetched from Supabase (stored per organisation), cached locally. ActivityRegistrationService reads from cache with a fallback to hardcoded defaults for offline scenarios. Design the rule schema to be extensible without code changes.
Contingency: If dynamic rules are not ready for initial release, ship with hardcoded rules and a feature flag that enables the remote-config path. Document the rule structure clearly so coordinators can trigger a rule update via a Supabase dashboard entry rather than a code deployment.
The last-used activity type stored in RegistrationPreferencesStore may become invalid if the organisation administrator deactivates that activity type between sessions. The Cubit would pre-populate a deleted type, and either the UI would show a missing item or submission would fail with a foreign-key constraint error.
Mitigation & Contingency
Mitigation: In RegistrationDefaultsManager, validate the retrieved last-used activity type ID against the current list of active types fetched from the activity type repository. If the stored ID is not in the active list, fall back to the first active type alphabetically.
Contingency: If validation cannot be performed offline, surface a non-blocking warning in the activity type step ('Your previously used activity type is no longer available') and require the user to make a new selection before advancing.