1 files changed, 77 insertions, 0 deletions
diff --git a/Core/Role/RoleHierarchy.php b/Core/Role/RoleHierarchy.php
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+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Security\Core\Role;
+
+/**
+ * RoleHierarchy defines a role hierarchy.
+ *
+ * @author Fabien Potencier <fabien.potencier@symfony-project.com>
+ */
+class RoleHierarchy implements RoleHierarchyInterface
+{
+    protected $hierarchy;
+    protected $map;
+
+    /**
+     * Constructor.
+     *
+     * @param array $hierarchy An array defining the hierarchy
+     */
+    public function __construct(array $hierarchy)
+    {
+        $this->hierarchy = $hierarchy;
+
+        $this->buildRoleMap();
+    }
+
+    /**
+     * Returns an array of all roles reachable by the given ones.
+     *
+     * @param RoleInterface[] $roles An array of RoleInterface instances
+     *
+     * @return RoleInterface[] An array of RoleInterface instances
+     */
+    public function getReachableRoles(array $roles)
+    {
+        $reachableRoles = $roles;
+        foreach ($roles as $role) {
+            if (!isset($this->map[$role->getRole()])) {
+                continue;
+            }
+
+            foreach ($this->map[$role->getRole()] as $r) {
+                $reachableRoles[] = new Role($r);
+            }
+        }
+
+        return $reachableRoles;
+    }
+
+    protected function buildRoleMap()
+    {
+        $this->map = array();
+        foreach ($this->hierarchy as $main => $roles) {
+            $this->map[$main] = $roles;
+            $visited = array();
+            $additionalRoles = $roles;
+            while ($role = array_shift($additionalRoles)) {
+                if (!isset($this->hierarchy[$role])) {
+                    continue;
+                }
+
+                $visited[] = $role;
+                $this->map[$main] = array_unique(array_merge($this->map[$main], $this->hierarchy[$role]));
+                $additionalRoles = array_merge($additionalRoles, array_diff($this->hierarchy[$role], $visited));
+            }
+        }
+    }
+}