---
phase: 01-authentication
plan: 02
subsystem: auth
tags: [dart, flutter, authentication, clean-architecture, repository-pattern, error-handling]

# Dependency graph
requires:
  - phase: 01-authentication
    plan: 01
    provides: Flutter project with Supabase integration
provides:
  - AuthUser data model for user representation
  - Custom exception hierarchy for authentication errors
  - AuthRepository interface for auth operations abstraction
affects: [01-03, 02-01, 03-01]

# Tech tracking
tech-stack:
  added: []
  patterns: [clean-architecture, repository-pattern, factory-constructors, exception-hierarchy]

key-files:
  created:
    - lib/features/authentication/data/models/auth_user.dart
    - lib/core/errors/auth_exceptions.dart
    - lib/features/authentication/domain/repositories/auth_repository.dart
  modified: []

key-decisions:
  - "AuthUser extends Supabase User with fromSupabase() factory for clean conversion"
  - "Comprehensive exception hierarchy with specific types for each auth error scenario"
  - "AuthRepository interface provides full auth API including OAuth and profile management"
  - "AuthExceptionFactory maps Supabase errors to custom exceptions with user-friendly messages"

patterns-established:
  - "Pattern 1: Factory constructors for data model conversion from external sources"
  - "Pattern 2: Exception factory pattern for mapping external errors to internal types"
  - "Pattern 3: Abstract repository interface following clean architecture principles"

# Metrics
duration: 30 min
completed: 2026-01-28
---

# Phase 1 Plan 2: Authentication Models and Interfaces Summary

**AuthUser model with Supabase integration, comprehensive exception hierarchy, and clean repository interface for authentication operations**

## Performance

- **Duration:** 30 min
- **Started:** 2026-01-28T14:06:15Z
- **Completed:** 2026-01-28T14:37:00Z
- **Tasks:** 3
- **Files modified:** 4

## Accomplishments
- Created AuthUser data model with proper null safety and Supabase integration
- Implemented comprehensive custom exception hierarchy for all authentication scenarios
- Defined complete AuthRepository interface with full authentication capabilities
- Established clean architecture patterns for data and domain layers

## Task Commits

Each task was committed atomically:

1. **Task 1: Create AuthUser model** - `c45bb22` (feat)
2. **Task 2: Create custom auth exceptions** - `b46cabe` (feat)
3. **Task 3: Create AuthRepository interface** - `06e3ea4` (feat)
4. **Task 4: Fix compilation errors** - `58f2b5b` (fix)

**Plan metadata:** (will be committed with planning docs)

## Files Created/Modified

- `lib/features/authentication/data/models/auth_user.dart` - AuthUser data model with Supabase conversion factory
- `lib/core/errors/auth_exceptions.dart` - Custom exception hierarchy with factory for error mapping
- `lib/features/authentication/domain/repositories/auth_repository.dart` - Abstract repository interface for auth operations

## Decisions Made

- AuthUser wraps Supabase User to maintain clean separation between data sources and domain models
- Exception hierarchy provides specific types for each authentication failure scenario
- AuthRepository interface includes comprehensive methods including OAuth, profile management, and session handling
- AuthExceptionFactory converts Supabase errors to user-friendly messages with proper error codes
- Used factory constructors for consistent data model conversion patterns

## Deviations from Plan

### Auto-fixed Issues

**1. [Rule 1 - Bug] Fixed DateTime parsing in AuthUser.fromSupabase()**

- **Found during:** Task 3 (AuthRepository interface creation)
- **Issue:** Supabase User timestamp fields couldn't be directly assigned to DateTime type
- **Fix:** Used DateTime.tryParse() with null safety handling for createdAt and lastSignInAt fields
- **Files modified:** lib/features/authentication/data/models/auth_user.dart
- **Verification:** Flutter analysis passes, no type assignment errors
- **Committed in:** 58f2b5b (Task 4 commit)

**2. [Rule 3 - Blocking] Fixed import path in AuthRepository**

- **Found during:** Task 3 (AuthRepository interface creation)
- **Issue:** Relative import path to auth_exceptions.dart was incorrect
- **Fix:** Updated import path to reach core/errors directory correctly
- **Files modified:** lib/features/authentication/domain/repositories/auth_repository.dart
- **Verification:** Import resolves correctly, compilation succeeds
- **Committed in:** 58f2b5b (Task 4 commit)

**3. [Rule 2 - Missing Critical] Added UnknownAuthException for error factory**

- **Found during:** Task 2 (Custom auth exceptions creation)
- **Issue:** AuthExceptionFactory tried to instantiate abstract AuthException class for unknown errors
- **Fix:** Added UnknownAuthException class extending AuthException for fallback error cases
- **Files modified:** lib/core/errors/auth_exceptions.dart
- **Verification:** AuthExceptionFactory now compiles without instantiation errors
- **Committed in:** 58f2b5b (Task 4 commit)

---

**Total deviations:** 3 auto-fixed (1 bug, 1 missing critical, 1 blocking)
**Impact on plan:** All fixes were necessary for correct compilation and functionality. No scope creep.

## Issues Encountered

- Flutter/Dart not in system PATH required adding Flutter bin directory to PATH for analysis
- DateTime type conversion from Supabase User fields required safe parsing with null checks
- Abstract AuthException class couldn't be instantiated, requiring concrete fallback class

## User Setup Required

None - no external service configuration required.

## Next Phase Readiness

Authentication domain foundation is established with:
- Clean AuthUser model ready for Supabase integration
- Comprehensive error handling system for all auth scenarios
- Complete repository interface ready for implementation

Ready for Phase 1 Plan 3: Supabase Authentication Implementation.

---
*Phase: 01-authentication*
*Completed: 2026-01-28*