Pimcore Multi-class inheritance

Concrete.php

<?php

namespace Website\Model\Object;

use Pimcore\Model\Object;
use Pimcore\Model\Object\AbstractObject;

class Concrete extends \Pimcore\Model\Object\Concrete
{

    /**
     * @var
     */
    private $adminEventHook;


    public $inheritableClasses = [];

    /**
     * An array of fields that were inherited from a parent
     * Customise this per extending class
     * @var array
     */
    protected $inheritableFields = [];

    /**
     * Fields that have been inherited from parents
     * @var array
     */
    private $inheritedFields = [];

    public function isAllowedInheritanceClass($parentClassId)
    {
        return $parentClassId == $this->getClassId() || in_array($parentClassId, $this->inheritableClasses);
    }

    public function preGetValue($key)
    {
        if (in_array($key, $this->getInheritableFields())) {
            return $this->getObjectValueWithInheritanceCheck($key);
        }

        return null;
    }


    /**
     * Based on getNextParentforInheritance but tweaked for preGetters
     * @return null|static
     */
    public function getInheritedValue($key)
    {
        if ($this->getParent() instanceof AbstractObject) {
            $parent = $this->getParent();
            while ($parent && $parent->getType() == "folder") {
                $parent = $parent->getParent();
            }
            if ($parent && ($parent->getType() == "object" || $parent->getType() == "variant")) {
                if ($this->isAllowedInheritanceClass($parent->getClassId())) {
                    $getter = 'get' . ucfirst($key);
                    if (method_exists($parent, $getter)) {
                        //set inherited fields to override in the admin panel
                        //as the preget value is overwritten in the concrete class for each
                        //object value
                        if (\Pimcore::inAdmin()) {
                            $this->initAdminEventHook();
                            $fieldDefinition = $this->getClass()->getFieldDefinition($key);
                            $this->inheritedFields[$key] = $this->getEditmodeDataForField($parent, $key, $fieldDefinition);
                        }

                        return $parent->$getter();
                    }
                }
            }
        }

        return null;
    }

    /**
     * Returns the list of fields for this object that can be inherited
     * @return array
     */
    public function getInheritableFields()
    {
        return $this->inheritableFields;
    }

    /**
     * Returns the list of fields for this object that were inherited
     * @return array
     */
    public function getInheritedFields()
    {
        return $this->inheritedFields;
    }

    public function getObjectValueWithInheritanceCheck($key)
    {
        if (in_array($key, $this->lazyLoadedFields)) {
            $data = $this->getClass()->getFieldDefinition($key)->preGetData($this);
        } else {
            $data = $this->$key;
        }

        if (is_null($data) || empty($data)) {
            return $this->getInheritedValue($key);
        }

        return $data;
    }

    /**
     * Provides an admin panel hook that is automatically applied if inheritance is deteected
     */
    private function initAdminEventHook()
    {
        if (!$this->adminEventHook) {
            $this->adminEventHook = \Pimcore::getEventManager()
                ->attach("admin.object.get.preSendData", function (\Zend_EventManager_Event $e) {
                    $object = $e->getParam('object');

                    $returnValueContainer = $e->getParam('returnValueContainer');
                    $data = $returnValueContainer->getData();

                    if ($object instanceof Concrete) {

                        $inheritedFields = $object->getInheritedFields();

                        foreach($inheritedFields as $fieldName=>$editmodeData) {
                            if (isset($data['metaData'][$fieldName])) {
                                $data['metaData'][$fieldName] = $editmodeData['metaData'];
                            }

                            //add the value
                            $data['data'][$fieldName] = $editmodeData['data'];
                        }

                    }

                    $returnValueContainer->setData($data);
                });
        }
    }

    protected function getEditmodeDataForField($object, $key, $fieldDefinition)
    {
        $getter = "get" . ucfirst($key);

        $editmodeData = [
            'data' => null,
            'metaData' => [
                'objectid' => $object->getId()
            ]
        ];

        if ((
            $fieldDefinition instanceof Object\ClassDefinition\Data\Relations\AbstractRelations
            && $fieldDefinition->getLazyLoading()
            && !$fieldDefinition instanceof Object\ClassDefinition\Data\ObjectsMetadata
            && !$fieldDefinition instanceof Object\ClassDefinition\Data\MultihrefMetadata
        )
        || $fieldDefinition instanceof Object\ClassDefinition\Data\Nonownerobjects
        ) {

            $refId = null;

            if ($fieldDefinition->isRemoteOwner()) {
                $refKey = $fieldDefinition->getOwnerFieldName();
                $refClass = Object\ClassDefinition::getByName($fieldDefinition->getOwnerClassName());
                if ($refClass) {
                    $refId = $refClass->getId();
                }
            } else {
                $refKey = $key;
            }

            $relations = $object->getRelationData($refKey, !$fieldDefinition->isRemoteOwner(), $refId);

            if (!empty($relations)) {
                $data = [];
                if ($fieldDefinition instanceof Object\ClassDefinition\Data\Href) {
                    $data = $relations[0];
                } else {
                    foreach ($relations as $rel) {
                        if ($fieldDefinition instanceof Object\ClassDefinition\Data\Objects) {
                            $data[] = [$rel["id"], $rel["path"], $rel["subtype"]];
                        } else {
                            $data[] = [$rel["id"], $rel["path"], $rel["type"], $rel["subtype"]];
                        }
                    }
                }
                $editmodeData['data'] = $data;
                $editmodeData['metaData']['objectid'] = $object->getId();
                $editmodeData['metaData']['inherited'] = true;
            }

        } else {

            $fieldData = $object->$getter();

            if ($fieldDefinition instanceof Object\ClassDefinition\Data\CalculatedValue) {
                $fieldData = new Object\Data\CalculatedValue($fieldDefinition->getName());
                $fieldData->setContextualData("object", null, null, null);
                $value = $fieldDefinition->getDataForEditmode($fieldData, $object, true);
            } else {
                $value = $fieldDefinition->getDataForEditmode($fieldData, $object, true);
            }

            if (!$fieldDefinition->isEmpty($fieldData)) {
                $editmodeData['metaData']['objectid'] = $object->getId();
                $editmodeData['metaData']['inherited'] = true;
                $editmodeData['data'] = $value;
            }



        }

        return $editmodeData;
    }

}