Integrate Activity Form and Submission Flow in Proxy Screen
epic-proxy-activity-registration-ui-task-014 — Embed ProxyActivityForm into ProxyRegistrationScreen and wire the submit button to dispatch a SubmitProxyActivity event to the BLoC. Handle loading (disable button, show progress), conflict (open DuplicateWarningDialog), success (navigate away + show snackbar), and error (show inline error banner) states from the BLoC.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 16 - 2 tasks
Can start after Tier 15 completes
Implementation Notes
Use BlocConsumer with separate listenWhen and buildWhen predicates to cleanly separate side effects (navigation, snackbar, dialog) from UI rebuilds. The DuplicateWarningDialog should be shown via showDialog — do not use a conditional widget in the tree for dialogs as it complicates state management. The SnackBar must be shown on the previous screen after pop, not on the current screen before pop; achieve this by passing a callback or using GoRouter's extra parameter to signal the parent screen to show the snackbar. Form validation (FormKey.currentState!.validate()) must be called before dispatching SubmitProxyActivity — do not let the BLoC perform form validation, as that is the form's concern.
Coordinate with the DuplicateWarningDialog from task-006 to ensure the dialog interface matches what is expected here.
Testing Requirements
Widget tests (flutter_test): stub BLoC in submitting state and verify button shows progress + is disabled; stub conflict state and verify DuplicateWarningDialog appears, tap 'Save Anyway' and verify ConfirmDuplicateSubmit event emitted, tap 'Cancel' and verify CancelSubmit event emitted; stub success state and verify navigation pop is called (use MockGoRouter); stub error state and verify inline error banner appears with error text. Unit tests: BLoC event handling for SubmitProxyActivity (success path, duplicate path, error path). Integration test: full flow — fill form, select mentor, submit, verify Supabase insert called with correct payload (use Supabase mock). Accessibility test: error banner announced as live region.
The bulk registration screen combines pre-filled defaults, a dynamic multi-select participant list, per-participant conflict badges, and a batch submission confirmation — making it one of the most complex screens in the application. Scope creep or underestimated interaction complexity could cause the epic to exceed its estimate significantly.
Mitigation & Contingency
Mitigation: Implement the bulk screen in two vertical slices: (1) participant selection and form submission without conflict handling, (2) conflict badge rendering and override flow. Validate slice 1 with coordinators before building slice 2.
Contingency: If the full conflict review UI cannot be completed within the epic, ship the bulk screen with a simplified 'skip all duplicates' fallback mode and defer per-participant override toggles to a follow-up sprint.
The proxy-registration-bloc must manage state across two distinct flows (single proxy and bulk) with branching conflict paths, intermediate buffering of bulk participant selections, and reliable state reset. Incorrect state transitions could leave the UI in a loading or stale-conflict state after submission.
Mitigation & Contingency
Mitigation: Model the BLoC state as a sealed class hierarchy with exhaustive pattern matching in the UI. Write state-machine unit tests that exercise every valid transition and assert that invalid transitions are no-ops. Use flutter_bloc's BlocObserver in debug builds to log all transitions.
Contingency: If BLoC state bugs surface in QA, introduce an explicit ResetToIdle event triggered on screen disposal to guarantee clean state, and add a 'Start over' affordance visible to the coordinator at any conflict step.
The typeahead peer mentor selector with multi-select mode may be difficult to operate with VoiceOver/TalkBack, particularly the dynamic search results list and the selected-chip removal controls, risking WCAG 2.2 AA non-compliance for screen reader users.
Mitigation & Contingency
Mitigation: Wrap all search result items and selected chips with explicit Semantics widgets providing role, label, and selected-state announcements. Test the selector with VoiceOver on iOS and TalkBack on Android during development, not only at QA time.
Contingency: If the multi-select typeahead cannot be made fully accessible within the sprint, provide an alternative flat scrollable list with checkboxes as a fallback mode, toggled by an accessibility-settings flag.
The peer mentor selector must apply RLS chapter-scope filtering to show only mentors the coordinator is responsible for. If the Supabase query for the selector does not correctly join against the coordinator's chapter assignments, coordinators may see mentors from other chapters, violating data isolation.
Mitigation & Contingency
Mitigation: Implement the selector's data query using the same RLS-aware Supabase client used by the contact list feature, which already handles chapter-scope filtering. Write an integration test with a multi-chapter coordinator fixture asserting cross-chapter mentors are not returned.
Contingency: If a data isolation breach is discovered, immediately add a client-side chapter_id filter as a defence-in-depth measure and audit selector query logs for any unauthorised cross-chapter results.