# Username Login Implementation - Summary

## Changes Made

### 1. Database Schema
**New Field Added:**
- `username` VARCHAR(100) - Used for login authentication
- Unique index on username field for performance and data integrity

**Existing Field Preserved:**
- `uname` - Continues to store account numbers for reference and display

### 2. Code Files Modified

#### user_access.php (Main Login Page)
**Changes:**
- Form input field name changed from `uname` to `username`
- Login query updated to search by username instead of account number
- Error message changed from "Invalid Account No" to "Invalid Username"
- Label changed from "ACCOUNT NUMBER" to "USERNAME"
- Label changed from "ACCOUNT PASSWORD" to "PASSWORD"
- Added logic to retrieve account number (uname) after username authentication

**Key Logic:**
```php
// Old: $uname = $_POST['uname'];
// New: $username = $_POST['username'];

// Old: WHERE uname='$uname'
// New: WHERE username='$username'

// After authentication, retrieve account number:
$uname = $row['uname']; // Get account number for session
```

#### include/class.user.php (User Class)
**Changes:**
- `login()` method parameter changed from `$uname` to `$username`
- SQL query updated to authenticate using username field
- Session still stores account number (uname) for backward compatibility

**Method Signature:**
```php
// Old: public function login($uname, $upass)
// New: public function login($username, $upass)
```

### 3. Migration Files Created

#### database_migration_add_username.sql
- SQL script to add username column to account table
- Creates unique index on username
- Includes commented options for populating initial data

#### MIGRATION_INSTRUCTIONS.md
- Step-by-step migration guide
- Testing checklist
- Rollback procedures
- Security recommendations

## Session Management

**Important:** The session variable `$_SESSION['uname']` still stores the account number, NOT the username. This ensures backward compatibility with all dashboard pages that reference the account number.

```php
// Session stores account number for compatibility
$_SESSION['uname'] = $uname; // This is the account number
```

## What Stays the Same

1. **Account Numbers (uname):** Still used throughout the system for:
   - Display purposes
   - Transaction references
   - Database relationships
   - Session identification

2. **Dashboard Pages:** No changes needed - they continue to use `$_SESSION['uname']` which contains the account number

3. **Admin Login:** Uses email authentication, no changes required

4. **OTP & PIN Authentication:** Continue to work with account numbers

## Migration Steps Required

### Before Going Live:

1. **Backup Database**
   ```bash
   mysqldump -u username -p database_name > backup_before_username_migration.sql
   ```

2. **Run SQL Migration**
   ```bash
   mysql -u username -p database_name < database_migration_add_username.sql
   ```

3. **Populate Usernames**
   Choose one approach:
   
   **Option A:** Use account numbers as usernames (simplest)
   ```sql
   UPDATE account SET username = uname WHERE username IS NULL;
   ```
   
   **Option B:** Generate from names
   ```sql
   UPDATE account SET username = LOWER(CONCAT(fname, '.', lname)) WHERE username IS NULL;
   ```
   
   **Option C:** Manual assignment through admin interface

4. **Make Username Required**
   ```sql
   ALTER TABLE account MODIFY COLUMN username VARCHAR(100) NOT NULL;
   ```

5. **Test Thoroughly**
   - Test login with new username
   - Verify OTP delivery
   - Check PIN authentication
   - Confirm dashboard access
   - Test transactions

## Security Improvements to Consider

1. **Password Hashing:** Currently passwords are stored in plain text. Consider:
   ```php
   // When creating account:
   $hashed_password = password_hash($password, PASSWORD_DEFAULT);
   
   // When verifying:
   if (password_verify($input_password, $stored_hash)) {
       // Login successful
   }
   ```

2. **SQL Injection Prevention:** Use prepared statements consistently (mostly done)

3. **Session Security:**
   ```php
   session_regenerate_id(true); // After successful login
   ```

4. **Username Validation:** Add rules for acceptable username formats

## Testing Checklist

- [ ] Database migration completed
- [ ] All accounts have usernames
- [ ] Login with username works
- [ ] Login with wrong username shows error
- [ ] Login with wrong password shows error
- [ ] OTP email sent correctly
- [ ] PIN authentication works
- [ ] Dashboard loads correctly
- [ ] Account number displays correctly
- [ ] Transactions work normally
- [ ] Session timeout works
- [ ] Logout works

## Rollback Procedure

If issues occur:

1. **Restore Database Backup**
   ```bash
   mysql -u username -p database_name < backup_before_username_migration.sql
   ```

2. **Revert Code Changes**
   - Restore original user_access.php
   - Restore original include/class.user.php

## Support Notes

- Admin login unchanged (uses email)
- All dashboard pages unchanged (use account number from session)
- Account numbers remain the primary identifier in the system
- Username is only used for login authentication
- Existing functionality preserved

## Future Enhancements

1. Add "Forgot Username" feature
2. Add username availability check during registration
3. Allow users to change their username
4. Add username format validation
5. Implement password strength requirements
6. Add login attempt limiting
7. Add two-factor authentication options
