refactor file uploading and add media picker errors

app/Exceptions/FileInvalidException.php

@@ -0,0 +1,37 @@
+<?php
+
+namespace App\Exceptions;
+
+use Exception;
+
+class FileInvalidException extends Exception
+{
+    /**
+     * The error code of the exception.
+     *
+     * @var int
+     */
+    protected $code;
+
+    /**
+     * The error message of the exception.
+     *
+     * @var string
+     */
+    protected $message;
+
+    /**
+     * Create a new exception instance.
+     *
+     * @param string $message
+     * @param int $code
+     * @return void
+     */
+    public function __construct(string $message, int $code = 0)
+    {
+        $this->message = $message;
+        $this->code = $code;
+
+        parent::__construct($message, $code);
+    }
+}