/*

  * Licensed to the Apache Software Foundation (ASF) under one

  * or more contributor license agreements.  See the NOTICE file

  * distributed with this work for additional information

  * regarding copyright ownership.  The ASF licenses this file

  * to you 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 org.apache.myfaces.resource;

 import java.io.InputStream;

 import java.net.MalformedURLException;

 import java.net.URL;

 import java.util.Set;

 import javax.faces.context.FacesContext;

 import org.apache.myfaces.shared.resource.ResourceLoader;

 import org.apache.myfaces.shared.resource.ResourceMeta;

 import org.apache.myfaces.shared.resource.ResourceMetaImpl;

 /**

  * A resource loader implementation which loads resources from the webapp root.

  * It uses the methods on ExternalContext for handle resources.

  * 

  */

 public class RootExternalContextResourceLoader extends ResourceLoader

 {

     public RootExternalContextResourceLoader()

     {

         super("");

     }

     protected Set<String> getResourcePaths(String path)

     {

         if (path.startsWith("/"))

         {

             return FacesContext.getCurrentInstance().getExternalContext().getResourcePaths(path);

         }

         else

         {

             return FacesContext.getCurrentInstance().getExternalContext().getResourcePaths('/' + path);

         }

     }

     @Override

     public String getResourceVersion(String path)

     {

         return null;

     }

     @Override

     public String getLibraryVersion(String path)

     {

         return null;

     }

     //@Override

     public URL getResourceURL(String resourceId)

     {

         try

         {

             if (resourceId.startsWith("/"))

             {

                 return FacesContext.getCurrentInstance().getExternalContext().getResource(

                     resourceId);

             }

             else

             {

                 return FacesContext.getCurrentInstance().getExternalContext().getResource(

                     '/' + resourceId);

             }

         }

         catch (MalformedURLException e)

         {

             return null;

         }

     }

     @Override

     public URL getResourceURL(ResourceMeta resourceMeta)

     {

         if (resourceMeta.getLocalePrefix() != null)

         {

             // the webapp root folder cannot be localized, 

             // but if the resource lives in /contracts/[contract-name] it can be.

             return null;

         }

         return getResourceURL(resourceMeta.getResourceIdentifier());

     }

     @Override

     public InputStream getResourceInputStream(ResourceMeta resourceMeta)

     {

         return FacesContext.getCurrentInstance().getExternalContext().getResourceAsStream(

             '/' + resourceMeta.getResourceIdentifier());

     }

     @Override

     public ResourceMeta createResourceMeta(String prefix, String libraryName, String libraryVersion,

                                            String resourceName, String resourceVersion)

     {

         return new ResourceMetaImpl(prefix, libraryName, libraryVersion, resourceName, resourceVersion);

     }

     @Override

     public boolean libraryExists(String libraryName)

     {

         //No library can be created in root resolver

         return false;

     }

 }