ImportRowModifier: provide target_property...

...also adjust the related form

refs #11949

application/forms/ImportRowModifierForm.php

@@ -25,6 +25,16 @@ class ImportRowModifierForm extends DirectorObjectForm
             'required'     => true,
         ));
 
+        $this->addElement('text', 'target_property', array(
+            'label'        => $this->translate('Target property'),
+            'description'  => $this->translate(
+                'You might want to write the modified value to another (new) property.' 
+                . ' This property name can be defined here, the original property would'
+                . ' remain unmodified. Please leave this blank in case you just want to'
+                . ' modify the value of a specific property'
+            ),
+        ));
+
         $error = false;
         try {
             $mods = $this->enumModifiers();

library/Director/Hook/PropertyModifierHook.php

@@ -9,6 +9,8 @@ abstract class PropertyModifierHook
 {
     protected $settings = array();
 
+    private $targetProperty;
+
     private $db;
 
     public function getName()
@@ -26,9 +28,20 @@ abstract class PropertyModifierHook
         return $class;
     }
 
+    public function setTargetProperty($property)
+    {
+        $this->targetProperty = $property;
+        return $this;
+    }
+
+    public function hasTargetProperty()
+    {
+        return $this->targetProperty !== null;
+    }
+
     public function getTargetProperty()
     {
-        return null;
+        return $this->targetProperty;
     }
 
     public function setDb(Db $db)

library/Director/Objects/ImportRowModifier.php

@@ -17,6 +17,7 @@ class ImportRowModifier extends DbObjectWithSettings
         'source_id'       => null,
         'property_name'   => null,
         'provider_class'  => null,
+        'target_property' => null,
         'priority'        => null,
     );
 
@@ -31,6 +32,7 @@ class ImportRowModifier extends DbObjectWithSettings
         if ($this->hookInstance === null) {
             $obj = new $this->provider_class;
             $obj->setSettings($this->getSettings());
+            $obj->setTargetProperty($this->target_property);
             $obj->setDb($this->connection);
             $this->hookInstance = $obj;
         }