<?php
/**
 * Geofeed Manager Configuration
 */

// Error reporting (disable in production)
error_reporting(E_ALL);
ini_set('display_errors', '0');

// Database configuration
define('DB_HOST', getenv('DB_HOST') ?: 'localhost');
define('DB_NAME', getenv('DB_NAME') ?: 'geofeed_manager');
define('DB_USER', getenv('DB_USER') ?: 'root');
define('DB_PASS', getenv('DB_PASS') ?: '');

// Application settings
define('APP_NAME', 'Geofeed Manager');
define('APP_VERSION', '1.0.0');
define('ITEMS_PER_PAGE', 25);

// Session configuration
session_start();

// Database connection
function getDB() {
    static $pdo = null;
    
    if ($pdo === null) {
        try {
            $pdo = new PDO(
                "mysql:host=" . DB_HOST . ";dbname=" . DB_NAME . ";charset=utf8mb4",
                DB_USER,
                DB_PASS,
                [
                    PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
                    PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
                    PDO::ATTR_EMULATE_PREPARES => false
                ]
            );
        } catch (PDOException $e) {
            die(json_encode(['error' => 'Database connection failed']));
        }
    }
    
    return $pdo;
}

// CSRF Protection
function generateCSRFToken() {
    if (empty($_SESSION['csrf_token'])) {
        $_SESSION['csrf_token'] = bin2hex(random_bytes(32));
    }
    return $_SESSION['csrf_token'];
}

function validateCSRFToken($token) {
    return isset($_SESSION['csrf_token']) && hash_equals($_SESSION['csrf_token'], $token);
}

// JSON Response helper
function jsonResponse($data, $statusCode = 200) {
    http_response_code($statusCode);
    header('Content-Type: application/json');
    echo json_encode($data);
    exit;
}

// Input sanitization
function sanitizeInput($input) {
    if (is_array($input)) {
        return array_map('sanitizeInput', $input);
    }
    return htmlspecialchars(trim($input), ENT_QUOTES, 'UTF-8');
}

// IP prefix validation
function isValidIpPrefix($prefix) {
    if (strpos($prefix, '/') !== false) {
        list($ip, $cidr) = explode('/', $prefix);
        
        if (!is_numeric($cidr)) {
            return false;
        }
        
        if (filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4)) {
            return $cidr >= 0 && $cidr <= 32;
        }
        
        if (filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV6)) {
            return $cidr >= 0 && $cidr <= 128;
        }
        
        return false;
    }
    
    return filter_var($prefix, FILTER_VALIDATE_IP) !== false;
}

// Country code validation
function isValidCountryCode($code) {
    if (empty($code)) return true;
    return preg_match('/^[A-Z]{2}$/i', $code);
}

// Region code validation (ISO 3166-2)
function isValidRegionCode($code) {
    if (empty($code)) return true;
    return preg_match('/^[A-Z]{2}-[A-Z0-9]{1,3}$/i', $code);
}