gistfile1.php

<?php
public function findPolicy($context = '') {
    $policy = array();
    $enabled = true;
    $context = !empty($context) ? $context : $this->xpdo->context->get('key');
    if ($context === $this->xpdo->context->get('key')) {
        $enabled = (boolean) $this->xpdo->getOption('access_resource_group_enabled', null, true);
    } elseif ($this->xpdo->getContext($context)) {
        $enabled = (boolean) $this->xpdo->contexts[$context]->getOption('access_resource_group_enabled', true);
    }
    if ($enabled) {
        if (empty($this->_policies) || !isset($this->_policies[$context])) {
            $accessTable = $this->xpdo->getTableName('modAccessResourceGroup');
            $policyTable = $this->xpdo->getTableName('modAccessPolicy');
            $resourceGroupTable = $this->xpdo->getTableName('modResourceGroupResource');
            $sql = "SELECT Acl.target, Acl.principal, Acl.authority, Acl.policy, Policy.data FROM {$accessTable} Acl " .
                    "LEFT JOIN {$policyTable} Policy ON Policy.id = Acl.policy " .
                    "JOIN {$resourceGroupTable} ResourceGroup ON Acl.principal_class = 'modUserGroup' " .
                    "AND (Acl.context_key = :context OR Acl.context_key IS NULL OR Acl.context_key = '') " .
                    "AND ResourceGroup.document = :resource " .
                    "AND ResourceGroup.document_group = Acl.target " .
                    "GROUP BY Acl.target, Acl.principal, Acl.authority, Acl.policy";
            $bindings = array(
                ':resource' => $this->get('id'),
                ':context' => $context
            );
            $query = new xPDOCriteria($this->xpdo, $sql, $bindings);
            if ($query->stmt && $query->stmt->execute()) {
                while ($row = $query->stmt->fetch(PDO::FETCH_ASSOC)) {
                    $policy['modAccessResourceGroup'][$row['target']][] = array(
                        'principal' => $row['principal'],
                        'authority' => $row['authority'],
                        'policy' => $row['data'] ? $this->xpdo->fromJSON($row['data'], true) : array(),
                    );
                }
            }
            $this->_policies[$context] = $policy;
        } else {
            $policy = $this->_policies[$context];
        }
    }
    return $policy;
}