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+---
+phase: 16
+title: Report Consolidation Toggle
+status: ready-for-planning
+created: 2026-04-09
+---
+
+# Phase 16 Context: Report Consolidation Toggle
+
+## Decided Areas (from Phase 15 CONTEXT.md — locked)
+
+These are locked — do not re-litigate during planning or execution.
+
+| Decision | Value |
+|---|---|
+| Consolidation scope | User access audit report only — site-centric permission report is unchanged |
+| Consolidation key | `UserLogin + PermissionLevel + AccessType + GrantedThrough` (4-field match) |
+| Source model | `UserAccessEntry` (already normalized, one user per row) |
+| Consolidation defaults OFF | Toggle must default to unchecked |
+| No API calls | Pure data transformation via `PermissionConsolidator.Consolidate()` |
+| Existing exports unchanged when OFF | Output must be identical to pre-v2.3 when toggle is OFF |
+
+## Discussed Areas
+
+### 1. Toggle Placement & UX
+
+**Decision:** New "Export Options" GroupBox in the left panel of both audit tabs, always visible.
+
+- Add a new `GroupBox` labeled "Export Options" below the existing "Scan Options" GroupBox
+- Contains a single `CheckBox` labeled **"Merge duplicate permissions"**
+- GroupBox is always visible (not hidden when results are empty)
+- The same GroupBox appears in both the User Access Audit tab and the site-centric Permissions tab
+- No pre-export dialog — the toggle is always accessible in the panel
+- Toggle applies to **both HTML and CSV exports** (user override of REQUIREMENTS.md CSV exclusion)
+
+### 2. Consolidated HTML Rendering
+
+**Decision:** Expandable sub-list for merged locations, with inline fallback for single-site rows.
+
+- When consolidation is ON, the by-user view shows consolidated rows
+- Each consolidated row has a "Sites" column:
+  - **1 location:** site title displayed inline (no badge/expand)
+  - **2+ locations:** clickable `[N sites]` badge that expands an inline sub-list of site URLs/titles below the row
+- Expandable sub-list uses the existing `toggleGroup()` JS pattern already in the HTML export
+- **By-site view is disabled** when consolidation is ON — only the by-user view is available (the view toggle is hidden or grayed out)
+- No "Consolidated view" indicator in the report header — report stands on its own
+
+### 3. Session Persistence Scope
+
+**Decision:** Session-scoped global setting, UI in both tabs.
+
+- Toggle state lives as a **session-scoped property** (ViewModel or shared service) — resets to OFF on app restart
+- The setting is **global** — one toggle state shared across all export types and tabs
+- UI presence: Export Options GroupBox in **both** User Access Audit tab and site-centric Permissions tab, reading/writing the same property
+- **Site-centric tab: toggle is present but no-op** — the checkbox is shown and functional (stores the value) but the site-centric export does not apply consolidation logic yet. This is intentional placeholder wiring for future phases.
+- User Access Audit exports (HTML and CSV) are the only ones that apply the consolidation when the toggle is ON
+
+## Deferred Ideas (out of scope for Phase 16)
+
+- Site-centric consolidation logic (toggle present in UI but no-op for site-centric exports)
+- Group expansion within consolidated rows (Phase 17)
+- Persistent consolidation preference across app restarts (decided: session-only for now)
+- "Consolidated view" report header indicator (decided: not needed)
+
+## code_context
+
+| Asset | Path | Reuse |
+|---|---|---|
+| PermissionConsolidator | `SharepointToolbox/Core/Helpers/PermissionConsolidator.cs` | Call `Consolidate()` to transform flat entries into consolidated list |
+| ConsolidatedPermissionEntry | `SharepointToolbox/Core/Models/ConsolidatedPermissionEntry.cs` | Output model from consolidator — has `Locations` list and `LocationCount` |
+| LocationInfo | `SharepointToolbox/Core/Models/LocationInfo.cs` | Location record within consolidated entry |
+| UserAccessEntry | `SharepointToolbox/Core/Models/UserAccessEntry.cs` | Input model — flat permission row |
+| UserAccessHtmlExportService | `SharepointToolbox/Services/Export/UserAccessHtmlExportService.cs` | Update to accept consolidation flag; render consolidated rows when ON |
+| UserAccessCsvExportService | `SharepointToolbox/Services/Export/UserAccessCsvExportService.cs` | Update to apply consolidation when toggle is ON |
+| UserAccessAuditViewModel | `SharepointToolbox/ViewModels/Tabs/UserAccessAuditViewModel.cs` | Add `MergePermissions` property; pass to export services |
+| UserAccessAuditView.xaml | `SharepointToolbox/Views/Tabs/UserAccessAuditView.xaml` | Add Export Options GroupBox with checkbox |
+| Scan Options GroupBox pattern | `SharepointToolbox/Views/Tabs/UserAccessAuditView.xaml` (lines 199-210) | Follow same GroupBox + CheckBox binding pattern |
+| toggleGroup() JS | `UserAccessHtmlExportService.cs` (inline JS) | Reuse for expandable location sub-lists |
+| PermissionConsolidatorTests | `SharepointToolbox.Tests/Helpers/PermissionConsolidatorTests.cs` | Reference for test patterns; add integration tests for export flow |
+
+---
+
+*Phase: 16-report-consolidation-toggle*
+*Context gathered: 2026-04-09 via discuss-phase*