BPVA Calendar App - Changelog

Account Linking Implementation (October 2025)

✅ Completed Features

Manual Account Linking System

• Implemented AccountLinkingService for Firestore-based account linking
• Support for linking Apple and Google accounts with different email addresses
• Enabled “Hide My Email” compatibility for Apple Sign-In
• Created bidirectional lookup system:
  • users/{uid}/linkedAccounts/{provider} - User’s linked accounts
  • account_links/{appleUserId} - Reverse lookup for Apple user IDs

Authentication Flow

• Primary Account: First sign-in method (Google or Apple)
• Secondary Account: Can be linked later with different email
• Google Calendar Access: Maintained regardless of sign-in method
• App Store Compliance: Apple Sign-In fully functional

Firestore Security Rules

• User Documents: Users can read/write their own profile and linked accounts
• Account Links: Users can create/update links they own (verified by primaryFirebaseUid)
• Privacy: Each user can only access their own linking data

🗑️ Removed Features

Debug/Test Code (No Longer Needed)

• Removed “Test Apple Sign-In” button from admin profile
• Removed “Debug Apple Sign-In” diagnostics button
• Deleted testAppleSignIn() method from AuthService
• Deleted checkAppleSignInStatus() method from AuthService

Obsolete Documentation

• apple-key-confusion-explained.md - JWT debugging docs
• apple-signin-issue-summary.md - Firebase linking issue analysis
• firebase-config-diagnostic.md - Configuration troubleshooting
• ipad-testing-guide.md - Initial testing notes
• ipad-testing-session-summary.md - Session notes

📝 Updated Documentation

Kept & Updated

• apple-signin-setup.md - Apple Developer Console configuration
• firebase-apple-signin-setup.md - Firebase Console setup
• manual-account-linking.md - Architecture and implementation details
• QUICK_START_MANUAL_LINKING.md - Developer implementation guide
• README.md - Updated with authentication features section

🔧 Technical Changes

Code Modifications

1. auth_service.dart
   • Added AccountLinkingService import
   • Replaced Firebase linkWithCredential() with manual linking
   • Updated unlinkAccount() to use manual unlinking
   • Added Firestore data loading in loadUserProfile() and refreshUserProfile()
   • Removed test/debug methods
2. firestore.rules
   • Added account_links collection rules
   • Added users/{userId}/linkedAccounts subcollection support (not used, but safe)
   • Fixed field name from primaryUid to primaryFirebaseUid
3. admin_my_profile_screen.dart
   • Removed test/debug UI buttons
   • Removed test dialog methods
   • Kept only production linking functionality

🎯 Key Benefits

1. Reliability: Manual linking via Firestore avoids Firebase SDK bugs
2. Flexibility: Emails don’t need to match between Google and Apple accounts
3. Privacy: Supports Apple’s “Hide My Email” feature
4. Compliance: Meets App Store requirements for Apple Sign-In
5. Maintainability: Clean, well-documented implementation

📱 User Experience

• Users sign in with Google (for Calendar access)
• Users can link their Apple ID from Admin Profile
• After linking, users can sign in with either method
• Unlinking is supported and properly cleans up Firestore data
• Linked accounts persist across app restarts

🔐 Security

• All linking operations verify user ownership
• Firestore rules prevent unauthorized access
• Primary Firebase UID controls data access
• Account links are user-specific and private

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Status: Production-ready ✅
Tested: iPad (iOS 18.7), Manual linking works perfectly
Deployed: Firestore rules updated and deployed