001/* 
002    Licensed to the Apache Software Foundation (ASF) under one
003    or more contributor license agreements.  See the NOTICE file
004    distributed with this work for additional information
005    regarding copyright ownership.  The ASF licenses this file
006    to you under the Apache License, Version 2.0 (the
007    "License"); you may not use this file except in compliance
008    with the License.  You may obtain a copy of the License at
009
010       http://www.apache.org/licenses/LICENSE-2.0
011
012    Unless required by applicable law or agreed to in writing,
013    software distributed under the License is distributed on an
014    "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015    KIND, either express or implied.  See the License for the
016    specific language governing permissions and limitations
017    under the License.  
018 */
019package org.apache.wiki.tags;
020
021import org.apache.logging.log4j.LogManager;
022import org.apache.logging.log4j.Logger;
023import org.apache.wiki.api.core.Attachment;
024import org.apache.wiki.api.core.Context;
025import org.apache.wiki.api.core.Engine;
026import org.apache.wiki.api.core.Page;
027import org.apache.wiki.api.exceptions.ProviderException;
028import org.apache.wiki.attachment.AttachmentManager;
029import org.apache.wiki.pages.PageManager;
030
031import javax.servlet.jsp.JspWriter;
032import javax.servlet.jsp.PageContext;
033import java.io.IOException;
034import java.util.List;
035
036
037/**
038 *  Iterates through the list of attachments one has.
039 *
040 *  <P><B>Attributes</B></P>
041 *  <UL>
042 *    <LI>page - Page name to refer to.  Default is the current page.
043 *  </UL>
044 *
045 *  @since 2.0
046 */
047// FIXME: Too much in common with IteratorTag - REFACTOR
048public class AttachmentsIteratorTag extends IteratorTag {
049    private static final long serialVersionUID = 0L;
050    
051    private static final Logger log = LogManager.getLogger( AttachmentsIteratorTag.class );
052
053    /**
054     *  {@inheritDoc}
055     */
056    @Override
057    public final int doStartTag()  {
058        m_wikiContext = (Context) pageContext.getAttribute( Context.ATTR_CONTEXT, PageContext.REQUEST_SCOPE );
059        final Engine engine = m_wikiContext.getEngine();
060        final AttachmentManager mgr = engine.getManager( AttachmentManager.class );
061        final Page page;
062
063        page = m_wikiContext.getPage();
064
065        if( !mgr.attachmentsEnabled() )
066        {
067            return SKIP_BODY;
068        }
069
070        try {
071            if( page != null && engine.getManager( PageManager.class ).wikiPageExists(page) ) {
072                final List< Attachment > atts = mgr.listAttachments( page );
073
074                if( atts == null ) {
075                    log.debug("No attachments to display.");
076                    // There are no attachments included
077                    return SKIP_BODY;
078                }
079
080                m_iterator = atts.iterator();
081
082                if( m_iterator.hasNext() ) {
083                    final Attachment  att = (Attachment) m_iterator.next();
084                    final Context context = m_wikiContext.clone();
085                    context.setPage( att );
086                    pageContext.setAttribute( Context.ATTR_CONTEXT, context, PageContext.REQUEST_SCOPE );
087                    pageContext.setAttribute( getId(), att );
088                } else {
089                    return SKIP_BODY;
090                }
091            } else {
092                return SKIP_BODY;
093            }
094
095            return EVAL_BODY_BUFFERED;
096        } catch( final ProviderException e ) {
097            log.fatal("Provider failed while trying to iterator through history",e);
098            // FIXME: THrow something.
099        }
100
101        return SKIP_BODY;
102    }
103
104    /**
105     *  {@inheritDoc}
106     */
107    @Override
108    public final int doAfterBody() {
109        if( bodyContent != null ) {
110            try {
111                final JspWriter out = getPreviousOut();
112                out.print(bodyContent.getString());
113                bodyContent.clearBody();
114            } catch( final IOException e ) {
115                log.error("Unable to get inner tag text", e);
116                // FIXME: throw something?
117            }
118        }
119
120        if( m_iterator != null && m_iterator.hasNext() ) {
121            final Attachment att = ( Attachment )m_iterator.next();
122            final Context context = m_wikiContext.clone();
123            context.setPage( att );
124            pageContext.setAttribute( Context.ATTR_CONTEXT,  context, PageContext.REQUEST_SCOPE );
125            pageContext.setAttribute( getId(), att );
126
127            return EVAL_BODY_BUFFERED;
128        }
129
130        return SKIP_BODY;
131    }
132
133}