Core authentication functionality providing login, registration, password reset, and cross-site authentication for the Extra Chill Platform.

Login System

User Login Process

// Handle login request
if (isset($_POST['extrachill_login'])) {
    $email = sanitize_email(wp_unslash($_POST['email']));
    $password = $_POST['password'];
    
    $user = wp_authenticate($email, $password);
    if (!is_wp_error($user)) {
        wp_set_auth_cookie($user->ID);
        wp_set_current_user($user->ID);
    }
}

Login Block Rendering

Gutenberg block provides unified login interface with:

• Email-based authentication
• Password validation
• Error handling
• Redirect management

Registration System

User Registration Flow

// Handle user registration
if (isset($_POST['extrachill_register'])) {
    $email = sanitize_email(wp_unslash($_POST['email']));
    $password = $_POST['password'];
    $display_name = sanitize_text_field(wp_unslash($_POST['display_name']));
    
    $user_id = wp_create_user($email, $password, $email);
    if (!is_wp_error($user_id)) {
        wp_update_user([
            'ID' => $user_id,
            'display_name' => $display_name
        ]);
    }
}

Registration Features

• Email validation
• Password strength requirements
• Display name customization
• Welcome email sending
• Cross-site user creation

Password Reset System

Reset Request Handler

// Process password reset request
if (isset($_POST['extrachill_reset_password'])) {
    $email = sanitize_email(wp_unslash($_POST['email']));
    $user = get_user_by('email', $email);
    
    if ($user) {
        $reset_key = get_password_reset_key($user);
        wp_mail($email, 'Password Reset', $reset_url);
    }
}

Reset Validation

• Secure token generation
• Time-limited reset links
• Email verification
• Cross-domain reset support

Browser Handoff Authentication

Handoff Token Generation

// Generate browser handoff token
function extrachill_generate_handoff_token($user_id) {
    $payload = [
        'user_id' => $user_id,
        'exp' => time() + (5 * 60), // 5 minutes
        'domain' => $_SERVER['HTTP_HOST']
    ];
    
    return jwt_encode($payload, get_option('extrachill_handoff_secret'));
}

Handoff Process

• JWT-based token exchange
• Cross-domain authentication
• Secure token validation
• Automatic user session creation

Security Features

Input Validation

• Email sanitization
• Password strength validation
• Nonce verification
• CSRF protection

Authentication Security

• Brute force protection
• Rate limiting
• Secure session handling
• Password hashing

API Endpoints

Authentication Endpoints

• POST /extrachill/v1/auth/login – User login
• POST /extrachill/v1/auth/register – User registration
• POST /extrachill/v1/auth/logout – User logout
• POST /extrachill/v1/auth/reset-password – Password reset

Token Management

• POST /extrachill/v1/auth/refresh – Refresh authentication token
• POST /extrachill/v1/auth/validate – Validate token
• POST /extrachill/v1/auth/handoff – Browser handoff

Integration Points

Multisite Integration

• Cross-site user authentication
• Network-wide session management
• Shared authentication state

Google OAuth Integration

• Social authentication
• Profile data import
• Account linking

Theme Integration

• Login form templates
• Registration form templates
• Password reset templates

Error Handling

Login Errors

• Invalid credentials
• Account locked
• Email not verified
• Network issues

Registration Errors

• Email already exists
• Weak password
• Invalid display name
• Rate limiting

Reset Errors

• Email not found
• Invalid token
• Token expired
• Rate limiting