Implement Claim Status Audit Timeline Widget
epic-expense-approval-workflow-coordinator-ui-task-010 — Create the ClaimStatusAuditTimeline Flutter widget that renders a chronological timeline of claim events fetched from ClaimEventsRepository. Display event type, timestamp, actor name, and optional notes for each event. Support expandable detail view and ensure accessibility with proper semantic ordering.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 1 - 540 tasks
Can start after Tier 0 completes
Implementation Notes
Separate the widget into ClaimStatusAuditTimeline (stateful, manages a Set
For timestamp formatting, use the intl package's DateFormat.yMMMd().add_jm() pattern with the device locale. Map event_type enum values to human-readable strings via a const Map
Testing Requirements
Widget tests: render with an empty list and assert 'No history yet' message. Render with 3 events and assert all rows appear in correct order. Tap the expand toggle on a row with notes and assert notes card becomes visible; tap again and assert it collapses. Assert Semantics labels are present on each row.
Golden tests: snapshot collapsed and expanded states. Unit tests: verify timestamp formatting logic for different locales. Test that events with null actor_id display 'System'. Target 90% line coverage for widget files.
Maintaining multi-select state across paginated list pages is architecturally complex in Flutter with Riverpod/BLoC. If the selection state is stored in the widget tree rather than the state layer, page transitions and list redraws can silently clear selections, causing coordinators to lose their multi-select and re-enter it.
Mitigation & Contingency
Mitigation: Store the selected claim ID set in a dedicated Riverpod StateNotifier outside the paginated list widget tree. The paginated list reads selection state from this provider and does not own it. Selection persists independently of list scroll position or page loads.
Contingency: If cross-page selection proves prohibitively complex, limit bulk selection to the currently visible page (add a clear warning in the UI) and prioritise single-page bulk approval for the initial release.
If a coordinator has the queue open while another coordinator approves claims from the same queue (possible in large organisations with shared chapter coverage), the Realtime update may arrive out of order or be missed during a reconnect, leaving the first coordinator's view stale and allowing them to attempt to approve an already-actioned claim.
Mitigation & Contingency
Mitigation: The ApprovalWorkflowService's optimistic locking (from the foundation epic) will catch the concurrent edit at the database level. The CoordinatorReviewQueueScreen should handle the resulting ConcurrencyException by removing the claim from the local list and showing a brief snackbar: 'This claim was already actioned by another coordinator.'
Contingency: Add a queue staleness indicator (a subtle 'last updated X seconds ago' label) and a manual refresh button as a fallback for coordinators who notice inconsistencies.
The end-to-end test requirement that a peer mentor receives a push notification within 30 seconds of coordinator approval depends on FCM delivery latency, which is outside the application's control and can vary significantly in CI/CD environments.
Mitigation & Contingency
Mitigation: Structure end-to-end tests to verify notification intent (correct FCM payload dispatched, correct Realtime event emitted) rather than actual device delivery timing. Use test doubles for FCM delivery in automated tests and reserve real-device delivery tests for manual pre-release validation.
Contingency: If notification timing requirements must be validated in automation, instrument the ApprovalNotificationService with a test hook that records dispatch timestamps and assert against those rather than actual FCM callbacks.