/*

  * Copyright 2007 Robin Helgelin

  *

  * Licensed under the Apache License, Version 2.0 (the "License");

  * you may not use this file except in compliance with the License.

  * You may obtain a copy of the License at

  *

  *     http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing, software

  * distributed under the License is distributed on an "AS IS" BASIS,

  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

  * See the License for the specific language governing permissions and

  * limitations under the License.

  */

 package nu.localhost.tapestry.acegi.components;

 import java.security.Principal;

 import org.apache.tapestry.Block;

 import org.apache.tapestry.annotations.Parameter;

 import org.apache.tapestry.ioc.annotations.Inject;

 import org.apache.tapestry.services.RequestGlobals;

 /**

  * Render it's body depending whether the user is logged in or not.

  * 

  * @author Robin Helgelin

  * @author Tapestry Project (doc comments)

  */

 public class IfLoggedIn {

     /**

      * Optional parameter to invert the test. If true, then the body is rendered when the test

      * parameter is false (not true).

      */

     @Parameter

     private boolean negate;

     /**

      * An alternate {@link Block} to render if the test parameter is false. The default, null, means

      * render nothing in that situation.

      */

     @Parameter(name = "else")

     private Block elseBlock;

     @Inject

     private RequestGlobals requestGlobals;

     private boolean test() {

         Principal principal = requestGlobals.getHTTPServletRequest().getUserPrincipal();

         return principal != null && principal.getName() != "";

     }

     /**

      * Returns null if the test method returns true, which allows normal rendering (of the body). If

      * the test parameter is false, returns the else parameter (this may also be null).

      */

     Object beginRender() {

         if (test() != negate) {

             return null;

         } else {

             return elseBlock;

         }

     }

     /**

      * If the test method returns true, then the body is rendered, otherwise not. The component does

      * not have a template or do any other rendering besides its body.

      */

     boolean beforeRenderBody() {

         return test() != negate;

     }

     void setup(String role, boolean negate, Block elseBlock) {

         this.negate = negate;

         this.elseBlock = elseBlock;

     }

 }