Uploader de Arquivos em PHP

FileUploader.php

<?php
session_start();

class FileUploader {

    private $file;

    private $mimesAllowed = [];
    
    public function upload($file, string $directory = '') {
        $this->setFile($file);

        if (!$this->validateMimeType()) {
            throw new Exception('irmão para');
        }

        $filename = $directory . $this->generateFileName();

        return move_uploaded_file($this->file['tmp_name'], $filename);
    }

    private function validateMimeType() {
        $mime = $this->getMimeType();

        return in_array($mime, $this->mimesAllowed);
    }

    private function getMimeType() {
        $mimes = explode('.', $this->file['name']);
        
        if (!$mimes) {
            throw new Exception('namoral coloca um arquivo q tenha uma extensão valida.');
        }
        return array_pop($mimes);
    }

    public function setMimesAllowed(array $mimeTypes) {
        $this->mimesAllowed = $mimeTypes;
    }

    private function setFile($file) {
        $this->file = $file;
    }

    private function generateFileName() {
        return md5(time()) . '.' . $this->getMimeType();
    }
}

$uploader = new FileUploader($_FILES['image']);

$uploader->setMimesAllowed(['png', 'jpg', 'gif']);

try {
    if ($uploader->upload($_FILES['image'])) {
        echo "foi";
    } else {
        echo "deu ruim no server";
    }
    
} catch(Exception $e) {
    var_dump($e->getMessage());
    if(isset($_SESSION['errors'])) {
        $_SESSION['errors'] += 1;
    } else {
        $_SESSION['errors'] = 1;
    }

    if($_SESSION['errors'] >= 3) {
        header("Location: https://www.youtube.com/watch?v=dQw4w9WgXcQ");
    }  
}

var_dump($_SESSION);