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<?php
/*
    Inherit resource group of last sibling added 
    or if no sibling is present of the current parent
*/
$debug = false;
$msg = array();

switch ($modx->event->name) {
 
    case 'OnDocFormSave':

        if ($mode == 'new') {// resource created
        
            $msg['mode'] = $mode;
            
            $msg['id'] = $resource->get('id');

            if($resource->get('parent')){
                
                // Parent
                $parentId = $resource->get('parent');
                
                $msg['parent'] = $parentId;
                
                // Siblings
                $c = $modx->newQuery('modResource', array('parent'=> $parentId  ));
                $c->sortby('menuindex', 'desc');
                
                $siblings = $modx->getCollection('modResource', $c);
                if (count($siblings)>0) {
                    
                    end($siblings);
                    prev($siblings);
                    
                    $sibling = prev($siblings);
                    $inheritId = $sibling->get('id');
                }

                
                // No siblings, use parent
                else {
                    $inheritId = $parentId;
                }

                $msg['inheritId'] = $inheritId;
    
                if($inheritId !== false) {

                    $childId = $resource->get('id');
                    $childResourceGroupCollection = $modx->getCollection('modResourceGroupResource', array('document' => $childId));
                    // Build an array of resource group IDs for this resource
                    $childResourceGroups = array();
                    foreach($childResourceGroupCollection as $group) {
                        $childResourceGroups[] = $group->get('document_group');
                    }
                    
                    $msg['childResourceGroups'] = $childResourcceGroups;
                    
                    $resourceGroups = $modx->getCollection('modResourceGroupResource',array('document' => $inheritId));
                   
                    $msg['resourceGroups'] = $resourceGroups; 
                   
                    if ($resourceGroups) {
                    // For each of the inherited resource groups, get the group ID and join the 
                    // new resource to that group.
                        foreach($resourceGroups as $group) {
                            $groupId = $group->get('document_group');
                            // If the resource is not already in the RG, join the group.
                            if ( ! in_array($groupId, $childResourceGroups)) {
                                $resource->joinGroup($groupId);
                            }
                        }
                    }
                    
                    
                }
            }
        }
        else {
           // existing resource was updated mod=='upd'
        }
        
    break;
}
if($debug){
    $modx->log(modX::LOG_LEVEL_ERROR, '[inheritResourceGroup]' . print_r($msg,true));
}