<?php

/**

* Copyright 2016 Open Infrastructure Foundation

* Licensed under the Apache License, Version 2.0 (the "License");

* you may not use this file except in compliance with the License.

* You may obtain a copy of the License at

* http://www.apache.org/licenses/LICENSE-2.0

* Unless required by applicable law or agreed to in writing, software

* distributed under the License is distributed on an "AS IS" BASIS,

* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

* See the License for the specific language governing permissions and

* limitations under the License.

**/

class NullAbleForeignKey extends ForeignKey

{

public function __construct($name, $object = null) {

parent::__construct($name, $object);

$this->defaultVal = !is_null($this->object) && $this->object instanceof Page && $this->name == 'ParentID' ? 0 : null ;

}

public function nullValue() {

return !is_null($this->object) && $this->object instanceof Page && $this->name == 'ParentID' ? 0 : null ;

}

public function requireField() {

$parts =

[

'datatype' => 'int',

'precision' => 11,

'null' => 'null',

'default' => $this->defaultVal,

'arrayValue' => $this->arrayValue

];

$values= ['type'=>'int', 'parts' => $parts];

DB::requireField($this->tableName, $this->name, $values);

}

public function scaffoldFormField($title = null, $params = null) {

$relationName = substr($this->name,0,-2);

$hasOneClass = $this->object->hasOneComponent($relationName);

if($hasOneClass && singleton($hasOneClass) instanceof Image) {

$field = UploadField::create($relationName, $title);

$field->getValidator()->setAllowedExtensions(array('jpg', 'jpeg', 'png', 'gif'));

} elseif($hasOneClass && singleton($hasOneClass) instanceof File) {

$field = UploadField::create($relationName, $title);

} else {

$titleField = (singleton($hasOneClass)->hasField('Title')) ? "Title" : "Name";

$list = DataList::create($hasOneClass);

// Don't scaffold a dropdown for large tables, as making the list concrete

// might exceed the available PHP memory in creating too many DataObject instances

if($list->count() < 100) {

$field = DropdownField::create($this->name, $title, $list->map('ID', $titleField));

$field->setEmptyString(' ');

} else {

$field = NumericField::create($this->name, $title);

}

}

return $field;

}

}