Implement Way Forward Task Service
epic-structured-post-session-report-form-engine-task-007 — Create the service layer for way-forward item lifecycle management: create, update, delete, and list items linked to a report. Implement business rules for coordinator assignment, status transitions (pending → in_progress → completed), and duplicate detection. Coordinate with WayForwardItemRepository for persistence and emit events for coordinator notification triggers.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 1 - 540 tasks
Can start after Tier 0 completes
Implementation Notes
Use the service layer pattern: WayForwardTaskService is a plain Dart class injected with IWayForwardItemRepository and IUserRoleValidator. Register as a Riverpod Provider so it can be overridden in tests. Event emission: use a StreamController
Duplicate detection query: `repository.findByReportIdAndTitle(reportId, title.trim().toLowerCase())` — the repository is responsible for case-insensitive matching. For the coordinator validation, keep the IUserRoleValidator call as a Future so the service can be tested with both sync and async fakes. The WayForwardItem domain object should be immutable (freezed or const constructor with copyWith). Do not couple the notification trigger logic directly in the service — only emit the event; a separate coordinator notification service listens to the stream.
Testing Requirements
Unit tests with mocked IWayForwardItemRepository and IUserRoleValidator: (1) createItem() happy path — verify repository.save() called and event emitted, (2) createItem() duplicate title → DuplicateWayForwardItemException, no repository call, (3) createItem() invalid coordinator → InvalidCoordinatorException, (4) updateItem() valid pending→in_progress transition emits event, (5) updateItem() invalid completed→pending transition → InvalidStatusTransitionException, (6) deleteItem() on pending item succeeds, (7) deleteItem() on completed item → CannotDeleteCompletedItemException, (8) repository throws StorageException → service propagates as WayForwardServiceException wrapping original, (9) listItems() returns items sorted by createdAt. Test event stream: subscribe before operation, assert event received with correct payload. Minimum 90% branch coverage.
Dynamically rendered form fields built from runtime JSON schema are significantly harder to make accessible than statically declared widgets — Flutter's Semantics tree must be correct for every possible field type and every validation state. Failures here block the entire feature for Blindeforbundet's visually impaired peer mentors.
Mitigation & Contingency
Mitigation: Define WCAG 2.2 AA semantics requirements for each field type before implementation and write widget tests using Flutter's SemanticsController for every type. Include a real-device VoiceOver test session in the acceptance gate for this epic before marking it done.
Contingency: If dynamic semantics prove too difficult to get right generically, implement field-type-specific Semantics wrappers (one per supported field type) instead of a single generic renderer, accepting slightly more code duplication in exchange for reliable accessibility.
The report-form-orchestrator must manage a complex state machine — schema loading, draft persistence, per-field validation, submission retries, and error recovery — across multiple async operations. Incorrect state transitions could result in lost user data, double submissions, or UI freezes.
Mitigation & Contingency
Mitigation: Define all Bloc states and events explicitly as sealed classes before writing any logic. Use a state machine diagram reviewed by the team before implementation. Write exhaustive Bloc unit tests covering every state transition, including concurrent events and network interruption mid-submission.
Contingency: If Bloc complexity becomes unmanageable, extract draft persistence into a separate DraftManagerCubit and keep report-form-orchestrator focused solely on the submit workflow. The additional granularity makes each component independently testable.
Organisations may require field types beyond the five currently specified (text, multiline, checkbox group, radio, date). If a new type is discovered during pilot testing, the dynamic-field-renderer must be extended, potentially requiring changes across multiple layers.
Mitigation & Contingency
Mitigation: Design dynamic-field-renderer as a registry of field-type renderers with a clear extension point. Document the pattern for adding a new field type so that it can be done in one file without touching existing renderers.
Contingency: If an unhandled field type is encountered at runtime, dynamic-field-renderer renders a labelled plain-text fallback widget and logs a warning so the missing type is surfaced in monitoring, preventing a crash while making the gap visible.