old/application/controllers/admin/Files.php

<?php
defined('BASEPATH') OR exit('No direct script access allowed');

class Files extends MY_Controller
{

    public function __construct()
    {
        parent::__construct();
        $this->load->model('FileModel', '', TRUE);
    }

    public function index()
    {
        $this->neededPermission('file.view');

        if(isset($_FILES['fileUpload'])) {
            $fileName = $_FILES['fileUpload']['name'];
            $tmpName = $_FILES['fileUpload']['tmp_name'];
            $fileSize = $_FILES['fileUpload']['size'];
            $fileType = $_FILES['fileUpload']['type'];

            $this->FileModel->uploadFile($fileName, $tmpName, $fileSize, $fileType, false);

            unset($_FILES['fileUpload']);

            redirect(base_url('admin/files'));
        }


        $files = $this->FileModel->getFileList();

        $this->load->view('admin/sidebar', ['title' => 'Alle Dateien', 'additionalStyles' => ['lib/jquery.fileupload.css', 'lib/jquery.fileupload-ui.css']]);
        $this->load->view('admin/files', ['files' => $files]);
        $this->load->view('admin/footer', ['additionalScripts' => ['lib/jquery.ui.widget.js', 'lib/jquery.iframe-transport.js', 'lib/jquery.fileupload.js', 'lib/jquery.fileupload-process.js', 'lib/jquery.fileupload-image.js', 'lib/jquery.fileupload-audio.js', 'lib/jquery.fileupload-video.js', 'lib/jquery.fileupload-validate.js', 'lib/jquery.fileupload-ui.js']]);
    }

    public function delete() {
        $this->neededPermission('file.delete');

        $id = filter_input(INPUT_POST, "id");
        $this->FileModel->delete($id);
    }

    public function uploadImage()
    {
        header("Content-Type: application/json");
        if (!$this->hasPermission('file.uploadManual')) {
            echo json_encode([
                'success' => false,
                'message' => '<b>Fehler beim Upload!</b> Aufgrund von zu geringen Zugriffsrechten konnte das Bild leider nicht hochgeladen werden. Sollte es sich dabei um ein Irrtum handeln, kontaktiere bitte einen Admin über das Kontaktformular.'
            ]);
            exit;
        }

        if(!isset($_POST['image']) || !isset($_POST['name']) || !isset($_POST['type']) || !isset($_POST['size'])) {
            echo json_encode([
                'success' => false,
                'message' => '<b>Fehler beim Upload!</b> Das hochgeladene Bild enthält fehlerhafte Informationen.'
            ]);
            exit;
        }
        $image = str_replace(' ', '+', $_POST['image']);
        $image = substr($image, strpos($image, ',') + 1);
        $image = base64_decode($image);

        $fileUrl = $this->FileModel->uploadFileByContent($image, $_POST['name'], $_POST['type'], $_POST['size']);

        echo json_encode([
            'success' => true,
            'message' => '<b>Bild erfolgreich hochgeladen!</b>',
            'url' => $fileUrl
        ]);
    }
}