Implement iOS photo library permission handling
epic-annual-impact-summary-core-services-task-011 — Add iOS-specific photo library permission flow to SummaryShareService. Request NSPhotoLibraryAddUsageDescription permission before saving to gallery. Handle all permission states: granted, denied, restricted, and limited (iOS 14+). When denied, display a settings-redirect dialog with plain-language explanation. Implement the save-to-gallery path using image_gallery_saver package with proper error handling and user feedback.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 3 - 413 tasks
Can start after Tier 2 completes
Implementation Notes
Add permission_handler and image_gallery_saver to pubspec.yaml. In Info.plist add NSPhotoLibraryAddUsageDescription (NOT NSPhotoLibraryUsageDescription — add-only permission is sufficient and less invasive). Use Permission.photos.request() for iOS < 14 and Permission.photosAddOnly for iOS 14+ (check Platform.version or use the permission_handler's built-in limited status). Wrap the entire flow in a SaveToGalleryUseCase class that accepts a PermissionHandler interface and a GallerySaver interface — this allows full mock-based unit testing without a real device.
For the settings dialog, use flutter_platform_aware dialogs only if the project already uses cupertino_alert_dialog; otherwise use Material AlertDialog for consistency. Ensure the 'Open Settings' button calls openAppSettings() from permission_handler, not a hardcoded URL scheme.
Testing Requirements
Widget tests using flutter_test with permission_handler mocked via a FakePermissionHandler: (1) mock granted → assert saveImage called and success snackbar shown; (2) mock denied → assert dialog shown with 'Open Settings' button; (3) mock restricted → assert informational dialog shown without settings button; (4) mock limited → assert save proceeds and limited-access snackbar shown; (5) simulate saveImage failure → assert error snackbar shown. Manual QA on physical iPhone with iOS 14+ for limited permission flow; verify Info.plist string appears in system permission alert.
Activity records may contain duplicate entries (as evidenced by the duplicate-detection feature dependency) or proxy-registered activities that should be attributed differently. Including duplicates or mis-attributed records would produce inflated stats, undermining trust in the summary.
Mitigation & Contingency
Mitigation: Implement the aggregation query to join against the deduplication-reviewed-flag on activity records and filter out unresolved duplicates. Coordinate with the duplicate-detection feature team to confirm the authoritative flag field before implementing the RPC. Include a data-quality warning in the summary when unresolved duplicates are detected.
Contingency: If deduplication state is unreliable at release time, add a prominent disclaimer in the summary UI noting that figures reflect all registered activities and may include duplicates pending review. Track a follow-up task to re-aggregate after deduplication runs.
Each organisation wants to define their own milestone thresholds (e.g., NHF's counting model differs from HLF's certification model). Implementing configurable thresholds may expand scope significantly if the configuration UI is expected in this epic.
Mitigation & Contingency
Mitigation: Scope this epic strictly to the evaluation engine and a hardcoded default threshold set. Define the MilestoneDefinition interface with an organisation_id discriminator so per-org configs can be loaded from the database in a later sprint. Build the admin configuration UI as a separate follow-on task outside this epic.
Contingency: If stakeholders require per-org milestone configuration before launch, deliver a JSON-based configuration file per org as an interim solution, loaded from Supabase storage, until a full admin UI is built.
Android 13+ restricts access to media collections and requires READ_MEDIA_IMAGES permission for gallery saves, while older Android versions use WRITE_EXTERNAL_STORAGE. Handling both permission models correctly across the device matrix is error-prone.
Mitigation & Contingency
Mitigation: Use the permission_handler Flutter package with version-aware permission requests abstracted behind the summary-share-service interface. Write platform-specific unit tests for both Android API levels in the test harness. Test on a minimum of three Android versions (API 29, 32, 34) in CI.
Contingency: If gallery save is broken on specific Android versions at launch, disable the 'Save to gallery' option on affected API levels and surface only clipboard and system share sheet, which require no media permissions.