university-esports-mainz.de/public/util/mysql_connect.php

<?php

require_once __DIR__."/dotenv.php";

class MySQLConnection {

    private int $port;
    private string $host;
    private string $user;
    private string $pass;
    private string $dbName;
    private mysqli $mysqli;

    public function __construct() {
        $this->host = 'localhost';
        $this->port = intval($_ENV['MYSQL_PORT']);
        $this->user = $_ENV['MYSQL_USER'];
        $this->pass = $_ENV['MYSQL_PASSWORD'];
		$this->dbName = $_ENV['MYSQL_DATABASE'];
        $this->createConn();
    }

    private function createConn(): void {
        $this->mysqli = new mysqli($this->host . ":" . $this->port, $this->user, $this->pass, $this->dbName);
		$this->mysqli->set_charset("utf8");
    }

    public function query($sql): mysqli_result|bool {
        return $this->mysqli->query($sql);
    }

	public function prepare($sql): bool|mysqli_stmt {
		return $this->mysqli->prepare($sql);
	}

    public function changeDB($dbName): void {
        $this->dbName = $dbName;
        $this->mysqli->select_db($dbName);
    }

    public function escape(string $string): string{
        return $this->mysqli->real_escape_string($string);
    }

    public function __destruct() {
        $this->mysqli->close();
    }

}