public static function uploadImage($nameOfImageInput)
 {
     $message = "";
     $target_dir = DIR_IMAGE_FOLDER;
     $imageId = Image::count() + 1;
     $imageExt = substr($_FILES[$nameOfImageInput]["name"], -4);
     $target_file = $target_dir . basename($imageId . $imageExt);
     $uploadOk = 1;
     $imageFileType = pathinfo($target_file, PATHINFO_EXTENSION);
     // Check if image file is a actual image or fake image
     if (isset($_POST["submit"])) {
         $check = getimagesize($_FILES[$nameOfImageInput]["tmp_name"]);
         if ($check !== false) {
             $uploadOk = 1;
         } else {
             $uploadOk = 0;
         }
     }
     // Check file size
     if ($_FILES[$nameOfImageInput]["size"] > 500000) {
         $message = "Sorry, your file is too large.";
         $uploadOk = 0;
         echo "loi";
         die;
     }
     // Allow certain file formats
     if ($imageFileType != "jpg" && $imageFileType != "png" && $imageFileType != "jpeg" && $imageFileType != "gif") {
         $uploadOk = 0;
         $message = $message . "Not Image file type!";
     }
     // Check if $uploadOk is set to 0 by an error
     if ($uploadOk == 0) {
         Session::put("imageMessage", $message);
         return "";
         // if everything is ok, try to upload file
     } else {
         if (move_uploaded_file($_FILES[$nameOfImageInput]["tmp_name"], $target_file)) {
             Image::create(['id' => $imageId, 'path' => $target_file]);
             echo "";
             return $target_file;
         } else {
             $message = $message . "Cannot upload!";
             Session::put("imageMessage", $message);
             return "";
         }
     }
 }