Introduce `User::can()' for checking whether a user has a given permission

The authentication manager already has the `hasPermission()' method but it lacks wildcard support
and uses stupid looping. Implementing this method on the user further saves a call to `User::getPermissions()'.

library/Icinga/User.php

@@ -187,7 +187,7 @@ class User
     }
 
     /**
-     * Return permission information for this user
+     * Get the user's permissions
      *
      * @return array
      */
@@ -197,13 +197,17 @@ class User
     }
 
     /**
-     * Setter for permissions
+     * Set the user's permissions
      *
      * @param   array $permissions
+     *
+     * @return  $this
      */
     public function setPermissions(array $permissions)
     {
-        $this->permissions = $permissions;
+        natcasesort($permissions);
+        $this->permissions = array_combine($permissions, $permissions);
+        return $this;
     }
 
     /**
@@ -444,4 +448,31 @@ class User
     {
         return (count($this->remoteUserInformation)) ? true : false;
     }
+
+    /**
+     * Whether the user has a given permission
+     *
+     * @param   string $permission
+     *
+     * @return  bool
+     */
+    public function can($permission)
+    {
+        if (isset($this->permissions['*']) || isset($this->permissions[$permission])) {
+            return true;
+        }
+        foreach ($this->permissions as $permitted) {
+            $wildcard = strpos($permitted, '*');
+            if ($wildcard !== false) {
+                if (substr($permission, 0, $wildcard) === substr($permitted, 0, $wildcard)) {
+                    return true;
+                } else {
+                    if ($permission === $permitted) {
+                        return true;
+                    }
+                }
+            }
+        }
+        return false;
+    }
 }

test/php/library/Icinga/UserTest.php

@@ -60,4 +60,19 @@ class UserTest extends BaseTestCase
         $user = new User('unittest');
         $user->setEmail('mySampleEmail at someDomain dot org');
     }
+
+    public function testPermissions()
+    {
+        $user = new User('test');
+        $user->setPermissions(array(
+            'test',
+            'test/some/specific',
+            'test/more/*'
+        ));
+        $this->assertTrue($user->can('test'));
+        $this->assertTrue($user->can('test/some/specific'));
+        $this->assertTrue($user->can('test/more/everything'));
+        $this->assertFalse($user->can('not/test'));
+        $this->assertFalse($user->can('test/some/not/so/specific'));
+    }
 }