// Copyright 2013 Thiago H. de Paula Figueiredo
//
// 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.
// Copyright 2013 Thiago H. de Paula Figueiredo
//
// 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 br.com.arsmachina.tapestry_rss.mixins;
import java.util.List;
import org.apache.tapestry5.MarkupWriter;
import org.apache.tapestry5.annotations.Parameter;
import org.apache.tapestry5.dom.Element;
import org.apache.tapestry5.ioc.annotations.Inject;
import org.apache.tapestry5.services.PageRenderLinkSource;
import br.com.arsmachina.tapestry_rss.Channel;
import br.com.arsmachina.tapestry_rss.pages.Rss;
import br.com.arsmachina.tapestry_rss.services.ChannelProvider;
/**
* Mixin that that adds a <code><link href="xxx" rel="alternate" type="application/rss+xml" title="yyy"/></code>
* element to the <code><head></code> of a page. The value passed to the <code>context</code>
* parameter should be handled by a {@link ChannelProvider} in order for the link to work.
*
* @author Thiago H. de Paula Figueiredo (http://machina.com.br/thiago)
* @see ChannelProvider
* @see Channel
* @tapestrydoc
*/
public class AddRssLink {
/**
* Page activation context that will be passed to the {@link Rss} page.
*/
@Parameter(required = true, allowNull = false)
private List<?> context;
/**
* <code>title</code> attribute to be used in the generated link.
*/
@Parameter
private String title;
@Inject
private PageRenderLinkSource pageRenderLinkSource;
/**
* Creates the RSS file URL and
* @param writer
*/
void afterRender(MarkupWriter writer) {
final Element head = writer.getDocument().getRootElement().find("head");
head.element("link", "rel", "alternate", "type", "application/rss+xml", "title", title,
"href", pageRenderLinkSource.createPageRenderLinkWithContext(Rss.class, context.toArray()).toAbsoluteURI());
}
}