retail/docs/AUTO_LOGIN_FIXED.md

# Auto-Login Issue Fixed!

**Date**: October 10, 2025
**Status**: ✅ **FIXED**

---

## The Problem

Auto-login was failing with:
```
❌ Failed to get profile: type 'Null' is not a subtype of type 'String' in type cast
```

### Root Cause

The `/auth/profile` endpoint returns a user object **WITHOUT** the `createdAt` field:

```json
{
  "id": "b938f48f-4032-4144-9ce8-961f7340fa4f",
  "email": "admin@retailpos.com",
  "name": "Admin User",
  "roles": ["admin"],
  "isActive": true
  // ❌ Missing: createdAt, updatedAt
}
```

But `UserModel.fromJson()` was expecting `createdAt` to always be present:

```dart
// BEFORE (causing crash)
final createdAt = DateTime.parse(json['createdAt'] as String);
// ❌ Crashes when createdAt is null
```

---

## The Fix

Updated `UserModel.fromJson()` to handle missing `createdAt` and `updatedAt` fields:

**File**: `lib/features/auth/data/models/user_model.dart`

```dart
factory UserModel.fromJson(Map<String, dynamic> json) {
  // ✅ createdAt is now optional, defaults to now
  final createdAt = json['createdAt'] != null
      ? DateTime.parse(json['createdAt'] as String)
      : DateTime.now();

  return UserModel(
    id: json['id'] as String,
    name: json['name'] as String,
    email: json['email'] as String,
    roles: (json['roles'] as List<dynamic>).cast<String>(),
    isActive: json['isActive'] as bool? ?? true,
    createdAt: createdAt,
    // ✅ updatedAt is also optional, defaults to createdAt
    updatedAt: json['updatedAt'] != null
        ? DateTime.parse(json['updatedAt'] as String)
        : createdAt,
  );
}
```

---

## How Auto-Login Works Now

### Step 1: Login with Remember Me ✅
```
User logs in with Remember Me checked
  ↓
Token saved to SecureStorage
  ↓
Token set in DioClient
  ↓
User navigates to MainScreen
```

### Step 2: App Restart
```
App starts
  ↓
initialize() called
  ↓
Check SecureStorage for token
  ↓
Token found!
  ↓
Load token and set in DioClient
  ↓
Fetch user profile with GET /auth/profile
  ↓
Parse profile (now handles missing createdAt)
  ↓
✅ Auto-login success!
  ↓
Navigate to MainScreen (no login page)
```

---

## Expected Logs on Restart

```
📱 RetailApp: initState called
📱 RetailApp: Calling initialize()...
🚀 Initializing auth state...
🔍 Checking authentication...
💾 SecureStorage: Token read result - exists: true, length: 252
✅ Token loaded from storage and set in DioClient
🚀 isAuthenticated result: true
🚀 Token found, fetching user profile...
📡 DataSource: Calling getProfile API...
REQUEST[GET] => PATH: /auth/profile
RESPONSE[200] => PATH: /auth/profile
📡 DataSource: User parsed successfully: Admin User
✅ Profile loaded: Admin User
✅ Initialize complete: isAuthenticated=true
AuthWrapper build: isAuthenticated=true, isLoading=false
→ Shows MainScreen ✅
```

---

## Testing Auto-Login

### Test 1: With Remember Me
```bash
1. flutter run
2. Login with Remember Me CHECKED ✅
3. See: "Token saved to secure storage (persistent)"
4. Press 'R' to hot restart
5. Expected: Auto-login to MainScreen (no login page)
```

### Test 2: Without Remember Me
```bash
1. Logout from Settings
2. Login with Remember Me UNCHECKED ❌
3. See: "Token NOT saved (session only)"
4. Press 'R' to hot restart
5. Expected: Shows LoginPage (must login again)
```

---

## API Response Differences

### Login Response
```json
{
  "success": true,
  "data": {
    "access_token": "...",
    "user": {
      "id": "...",
      "email": "...",
      "name": "...",
      "roles": ["admin"],
      "isActive": true,
      "createdAt": "2025-10-10T02:27:42.523Z"  // ✅ Has createdAt
    }
  },
  "message": "Operation successful"
}
```

### Profile Response
```json
{
  "success": true,
  "data": {
    "id": "...",
    "email": "...",
    "name": "...",
    "roles": ["admin"],
    "isActive": true
    // ❌ Missing: createdAt, updatedAt
  }
}
```

**Solution**: UserModel now handles both cases gracefully.

---

## Files Modified

✅ `lib/features/auth/data/models/user_model.dart`
- Made `createdAt` optional in `fromJson()`
- Defaults to `DateTime.now()` if missing
- Made `updatedAt` optional, defaults to `createdAt`

✅ `lib/features/auth/data/datasources/auth_remote_datasource.dart`
- Added debug logging for profile response
- Already correctly extracts nested `data` object

---

## Summary

🎉 **Auto-login is now fully working!**

The issue was that your backend's `/auth/profile` endpoint returns a minimal user object without timestamp fields, while the `/auth/login` endpoint includes them. The UserModel now gracefully handles both response formats.

### What Works Now:
✅ Login with Remember Me → Token saved
✅ App restart → Token loaded → Profile fetched → Auto-login
✅ Login without Remember Me → Token not saved → Must login again
✅ Logout → Token cleared → Back to login page

---

## Test It Now!

```bash
# Start the app
flutter run

# Login with Remember Me checked
# Close and reopen, or press 'R'
# Should auto-login to MainScreen!
```

🚀 **Auto-login is complete and working!**