Gallery with photos stored in folder determined by Address

GalleryPhoto.php

<?php

class GalleryPhoto extends DataObject {
    private static $db = array (
	'Caption' => 'Varchar'
    );

    private static $has_one = array (
	'Photo' => 'Image',
	'ProjectPage' => 'ProjectPage'
    );

    private static $summary_fields = array (
	'GridThumbnail' => 'Photo Thumbnail',
	'Caption' => 'Photo Caption',
	'Photo.Filename' => 'Photo Filename'
    );

    public function getGridThumbnail() {
	if($this->Photo()->exists()) {
	    return $this->Photo()->CroppedImage(50,50);
	}
	return '(no photo)';
    }

    public function getCMSFields() {
	$fields = FieldList::create(
	    TextField::create('Caption'),
	    $photo = UploadField::create('Photo')
	);
	$photo->setFolderName($this->ProjectPage()->getField('Address'));
	$photo->getValidator()->setAllowedExtensions(array('png','jpg','jpeg','gif'));

	return $fields;
    }

}

?>

ProjectPage.php

<?php

class ProjectPage extends Page {

    private static $db = array(
	'Start' => 'Date',
	'End' => 'Date',
	'Address' => 'Varchar(100)',
	'Description' => 'Text',
	'Status' => "Enum('Future, Current, Recent, Past','Future')"
    );

    private static $has_one = array (
	'Photo' => 'Image'
    );

    private static $has_many = array (
	'Gallery' => 'GalleryPhoto'
    );

    private static $can_be_root = false;

    public function getCMSFields() {
	$fields = parent::getCMSFields();
	$fields->removeFieldFromTab('Root.Main','Content');
	$fields->removeFieldFromTab('Root.Main','MenuTitle');
	$fields->removeFieldFromTab('Root.Main','Metadata');
	$fields->addFieldToTab('Root.Main', TextField::create('Title','Project Title'),'URLSegment'); 
	$fields->addFieldToTab('Root.Main', DateField::create('Start','Project Start Date')->setConfig('showcalendar',true),'');
	$fields->addFieldToTab('Root.Main', DateField::create('End','Project End Date')->setConfig('showcalendar',true),'');
	$fields->addFieldToTab('Root.Main', TextField::create('Address','Project Address'),'');
	$fields->addFieldToTab('Root.Main', TextareaField::create('Description','Project Description'),'');
	$fields->addFieldToTab('Root.Main', DropdownField::create('Status','Project Status', singleton('ProjectPage')->dbObject('Status')->enumValues()),'');
	$fields->addFieldToTab('Root.Main', $photo = UploadField::create('Photo','Project Photo'),'');
	$photo->getValidator()->setAllowedExtensions(array('png','jpg','jpeg','gif'));
	$photo->setFolderName($this->getField('Address'));
	$fields->addFieldToTab('Root.Main', GridField::create(
	    'Gallery',
	    'Project Gallery',
	    $this->Gallery(),
	    GridFieldConfig_RecordEditor::create() 
	));

	return $fields;
    }
}

class ProjectPage_Controller extends Page_Controller {

}

?>