<?php
// db/config.php
// Database configuration with fallback for XAMPP/Localhost

// 1. Try environment variables (for Cloud/VM environments)
$db_host = getenv('DB_HOST');
$db_name = getenv('DB_NAME');
$db_user = getenv('DB_USER');
$db_pass = getenv('DB_PASS');

// 2. Fallback to XAMPP defaults if not set
if ($db_host === false) $db_host = 'localhost';
if ($db_name === false) $db_name = 'car_dealership';
if ($db_user === false) $db_user = 'root';
if ($db_pass === false) $db_pass = ''; // Default XAMPP password is empty

// Define constants if not already defined
if (!defined('DB_HOST')) define('DB_HOST', $db_host);
if (!defined('DB_NAME')) define('DB_NAME', $db_name);
if (!defined('DB_USER')) define('DB_USER', $db_user);
if (!defined('DB_PASS')) define('DB_PASS', $db_pass);

function db() {
    static $pdo;
    if (!$pdo) {
        try {
            $dsn = 'mysql:host='.DB_HOST.';dbname='.DB_NAME.';charset=utf8mb4';
            $pdo = new PDO($dsn, DB_USER, DB_PASS, [
                PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
                PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
            ]);
        } catch (PDOException $e) {
            // Special handling: If database not found, try connecting without DB name
            // This is useful for the installer script to create the DB
            if ($e->getCode() == 1049) { // Unknown database
                $dsn_no_db = 'mysql:host='.DB_HOST.';charset=utf8mb4';
                try {
                    $pdo = new PDO($dsn_no_db, DB_USER, DB_PASS, [
                        PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
                        PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
                    ]);
                } catch (PDOException $ex) {
                    die("Database connection failed: " . $ex->getMessage());
                }
            } else {
                die("Database connection failed: " . $e->getMessage());
            }
        }
    }
    return $pdo;
}