FileElement: Add getValue(), hasValue() and related code

src/FormElement/FileElement.php

@@ -2,10 +2,15 @@
 
 namespace ipl\Html\FormElement;
 
+use ipl\Html\Form;
+
 class FileElement extends InputElement
 {
     protected $type = 'file';
 
+    /** @var array of \GuzzleHttp\Psr7\UploadedFile objects */
+    protected $value = [];
+
     public function setValue($value)
     {
         return $this;
@@ -19,4 +24,33 @@ public function getNameAttribute()
 
         return parent::getNameAttribute();
     }
+
+    public function getValueAttribute()
+    {
+        return $this->getName();
+    }
+
+    public function onRegistered(Form $form)
+    {
+        $this->value = $form->getRequest()->getUploadedFiles();
+    }
+
+    public function hasValue()
+    {
+        if (empty($this->value)) {
+            return false;
+        }
+
+        $file = $this->value[$this->getName()];
+        if ($this->getAttributes()->has('multiple')) {
+            return $file[0]->getError() !== UPLOAD_ERR_NO_FILE;
+        }
+
+        return $file->getError() !== UPLOAD_ERR_NO_FILE;
+    }
+
+    public function getValue()
+    {
+        return $this->hasValue() ? $this->value[$this->getName()] : null;
+    }
 }