/*
 * Copyright (C) 2005 Alfresco, Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.

 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.

 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

 * As a special exception to the terms and conditions of version 2.0 of 
 * the GPL, you may redistribute this Program in connection with Free/Libre 
 * and Open Source Software ("FLOSS") applications as described in Alfresco's 
 * FLOSS exception.  You should have recieved a copy of the text describing 
 * the FLOSS exception, and it is also available here: 
 * http://www.alfresco.com/legal/licensing"
 */
package org.alfresco.repo.template;

import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.List;

import freemarker.template.TemplateMethodModelEx;
import freemarker.template.TemplateModelException;
import freemarker.template.TemplateScalarModel;

/**
 * @author David Caruana
 * 
 * Custom FreeMarker Template language method.
 * <p>
 * Encode URL for HTML.
 * <p>
 * Usage: urlencode(String url)
 */
public final class UrlEncodeMethod implements TemplateMethodModelEx
{
    /**
     * @see freemarker.template.TemplateMethodModel#exec(java.util.List)
     */
    public Object exec(List args) throws TemplateModelException
    {
        String result = "";
        
        if (args.size() == 1)
        {
            Object arg0 = args.get(0);
            if (arg0 instanceof TemplateScalarModel)
            {
                try
                {
                    // TODO: Support other encodings, although
                    //       http://java.sun.com/j2se/1.4.2/docs/api/java/net/URLEncoder.html
                    //       recommends UTF-8
                    result = URLEncoder.encode(((TemplateScalarModel)arg0).getAsString(), "UTF-8");
                }
                catch (UnsupportedEncodingException e)
                {
                    // fallback to original url
                    result = ((TemplateScalarModel)arg0).getAsString();
                }
            }
        }
        
        return result;
    }
}