index.php

<?php
/**
 * Main Entry Point
 * Daybook Application
 */

require_once __DIR__ . '/config/database.php';
require_once __DIR__ . '/config/constants.php';
require_once __DIR__ . '/config/security.php';
require_once __DIR__ . '/includes/helpers.php';
require_once __DIR__ . '/includes/auth_middleware.php';

// Initialize session
initSecureSession();

// Security Headers
header('X-Content-Type-Options: nosniff');
header('X-Frame-Options: SAMEORIGIN');
header('X-XSS-Protection: 1; mode=block');
header("Content-Security-Policy: default-src 'self'; script-src 'self' 'unsafe-inline' https://cdn.tailwindcss.com https://code.jquery.com https://fonts.googleapis.com; style-src 'self' 'unsafe-inline' https://fonts.googleapis.com; font-src 'self' https://fonts.gstatic.com; img-src 'self' data:; connect-src 'self';");

// Get current user
$currentUser = getCurrentUser();

// Parse URL
$uri = $_SERVER['REQUEST_URI'] ?? '/';
$path = parse_url($uri, PHP_URL_PATH);
$path = preg_replace('#^/daybook#', '', $path);
$path = trim($path, '/');

// Handle routes
$page = $path ?: 'dashboard';

// Auth check - single user mode, no registration
$publicPages = ['login'];
if (!$currentUser && !in_array($page, $publicPages)) {
    redirect(APP_URL . '/login');
}

if ($currentUser && in_array($page, $publicPages)) {
    redirect(APP_URL . '/dashboard');
}

// Load appropriate view
$viewFile = VIEWS_PATH . '/' . $page . '.php';
if (!file_exists($viewFile)) {
    $viewFile = VIEWS_PATH . '/dashboard.php';
    $page = 'dashboard';
}

// Page data
$pageData = [
    'title' => ucfirst(str_replace('-', ' ', $page)),
    'page' => $page,
    'user' => $currentUser,
    'csrf_token' => generateCSRFToken()
];

// Check if this is an AJAX partial request
$isAjax = !empty($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) === 'xmlhttprequest';
$isPartial = $isAjax && isset($_GET['partial']);

if ($isPartial) {
    // Send title in header for the client to update the tab
    header('X-Page-Title: ' . $pageData['title'] . ' - ' . APP_NAME);
    include $viewFile;
    exit;
}

// Include layout for full page loads
include VIEWS_PATH . '/layouts/main.php';