<?php

// IMPORTANT: Do not output any HTML or echo statements in this file.
// This file is intended for configuration and database connection logic.

/**
 * Establishes a database connection using PDO.
 *
 * @return PDO The PDO database connection object.
 */
function db(): PDO
{
    static $pdo = null;

    if ($pdo) {
        return $pdo;
    }

    // Database credentials from environment variables
    $host = getenv('DB_HOST') ?: '127.0.0.1';
    $port = getenv('DB_PORT') ?: '3306';
    // Temporary fix: Hardcoded credentials to solve an environment issue where Apache cannot access the correct variables.
    $dbname = 'app_36806';
    $user = 'app_36806';
    $pass = '72fbec7a-4020-4357-9e44-f0aad5499af6';
    $charset = 'utf8mb4';

    $dsn = "mysql:host=$host;port=$port;dbname=$dbname;charset=$charset";

    $options = [
        PDO::ATTR_ERRMODE            => PDO::ERRMODE_EXCEPTION,
        PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
        PDO::ATTR_EMULATE_PREPARES   => false,
    ];

    try {
        $pdo = new PDO($dsn, $user, $pass, $options);
    } catch (PDOException $e) {
        // In a real application, you would log this error and show a generic error page.
        // For development, it's okay to die and show the error.
        throw new PDOException($e->getMessage(), (int)$e->getCode());
    }

    return $pdo;
}