# Redirect Loop Fix - NuxSaas Installation

## Problem
The system was experiencing `ERR_TOO_MANY_REDIRECTS` because of circular redirects between installation checks and route handling.

## Root Cause
1. `header.php` was checking installation status on every page load
2. Installation pages were redirecting back to themselves
3. No proper separation between installation routes and protected routes

## Solution

### 1. Enhanced Route Handling (`index.php`)
- Added smart route detection for installation vs protected routes
- Added installation status checks before redirecting
- Proper fallback to appropriate default pages

### 2. Safe Database Connection (`app/include/db_safe.php`)
- Created utility functions for safe database connections
- Functions: `getSafeDbConnection()`, `isInstalled()`, `hasSubscriptionTables()`, `configExists()`
- No redirects, just returns true/false status

### 3. Updated Header Files

#### `app/include/header.php`
- Added route-aware redirect logic
- Only checks installation if not already on installation routes
- Proper separation of concerns

#### `app/include/auth_header.php`
- Safe header for login/auth pages
- Only redirects when appropriate

#### `app/include/install_header.php` (New)
- Safe header specifically for installation pages
- No installation checks or redirects

#### `app/include/install_footer.php` (New)
- Proper closing for installation pages

### 4. Updated Installation Pages
- `install.php`: Now uses `install_header.php`
- `register.php`: Now uses `install_header.php`
- `index.php` (login): Removed redundant checks

### 5. Enhanced Installation Check (`check_installation.php`)
- Route-aware checking
- Only performs checks when not on installation routes
- Better error handling

## Flow Prevention
1. **Onboarding** → **Install** → **Login** → **Dashboard**
2. No circular redirects between routes
3. Each page type uses appropriate headers
4. Installation status properly tracked

## Benefits
- ✅ No more redirect loops
- ✅ Proper installation flow
- ✅ Safe database connections
- ✅ Better separation of concerns
- ✅ Maintains security checks

## Usage
The system now properly handles:
- First-time installation
- Partial installations
- Database connection issues
- User authentication
- Route protection

All while preventing redirect loops!
