Org Hierarchy Navigator: Search and Breadcrumb Display
epic-admin-portal-core-services-task-014 — Extend OrgHierarchyNavigator with an inline search field that filters visible nodes in real time using OrgHierarchyService.searchNodes(). Add a breadcrumb bar below the tree that shows the path from root to the currently selected node. Both features must meet WCAG 2.2 AA semantics.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 4 - 323 tasks
Can start after Tier 3 completes
Implementation Notes
Store search state (query string, filtered results) as a separate SearchState data class in the widget's local state alongside expansionState. When query is non-empty, replace the main tree ListView with a flat SearchResultsList; when cleared, reinstate the tree. This avoids complex diffing of the recursive tree widget. For breadcrumbs, call OrgHierarchyService.getAncestors(nodeId) once on node selection; if ancestors are already embedded in the OrgNode model (parentId chain), traverse the cached tree in-memory without an extra service call.
Make BreadcrumbBar a horizontally scrollable SingleChildScrollView to handle deep hierarchies without overflow. Use design tokens for breadcrumb separator (e.g., '›' character, text-secondary color) to stay consistent with the wider admin portal theme.
Testing Requirements
Widget tests (flutter_test): (1) typing a query triggers searchNodes after debounce and re-renders filtered list; (2) clearing query restores pre-search expansion state; (3) selecting a node populates breadcrumb with correct ancestor path; (4) tapping a breadcrumb segment fires onNodeSelected with that ancestor's node; (5) empty-results state renders a 'No results' message. Accessibility test: use SemanticsController to assert that search field and each breadcrumb segment have correct semantic labels. Contrast compliance verified via Flutter's debugCheckHasMediaQuery color-scheme assertions and manual design-token audit.
OrgHierarchyNavigator rendering NHF's full 1,400-chapter tree in a single widget may cause Flutter frame-rate drops below 60 fps on mid-range devices, making the navigator unusable for NHF national admins.
Mitigation & Contingency
Mitigation: Implement lazy expansion: only load immediate children on node expand rather than the full tree upfront. Use virtual scrolling for long sibling lists. Test with a synthetic 1,400-node dataset on a low-end Android device during development.
Contingency: If lazy expansion is insufficient, replace the tree widget with a paginated drill-down navigator (select level → select child) that avoids rendering more than 50 nodes at a time.
Bufdir may update their required export column structure or file format during or after development. If the AdminExportService hardcodes the current Bufdir schema, any format change requires a code release rather than a config update.
Mitigation & Contingency
Mitigation: Drive the Bufdir column mapping from a configuration repository rather than hardcoded constants. Abstract column definitions into a named schema config so that format changes require only a config update and re-deployment without service logic changes.
Contingency: If Bufdir format changes post-launch, release a config update within one sprint. If the change is structural (new required sections), scope a targeted service update and communicate timeline to partner organisations.
Role transition side-effects in UserManagementService (e.g., certification expiry removing mentor from chapter listing, pause triggering coordinator notification) may interact with external services like HLF's website sync. Incomplete side-effect handling could leave the system in an inconsistent state.
Mitigation & Contingency
Mitigation: Model side-effects as explicit domain events published after the primary state change is persisted. Implement event handlers as idempotent operations so re-processing is safe. Write integration tests that assert all side-effects fire correctly for each role transition type.
Contingency: If a side-effect fails after the primary change is persisted, log the failure with full context and trigger a manual reconciliation alert to the on-call team. Provide an admin-accessible re-trigger action for failed side-effects.
If AdminStatisticsService cache TTL is set too long, org_admin may see significantly stale KPI values (e.g., a mentor newly paused an hour ago still appears as active), undermining trust in the dashboard.
Mitigation & Contingency
Mitigation: Default cache TTL to 5 minutes with a manual refresh action on the dashboard. Implement cache invalidation triggered by UserManagementService write operations that affect counted entities.
Contingency: If staleness causes org admin complaints post-launch, reduce TTL to 60 seconds and introduce a real-time Supabase subscription for high-impact counters (paused mentors, expiring certifications).