/*
 * The Apache Software License, Version 1.1
 *
 *
 * Copyright (c) 2001 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Apache Cocoon" and "Apache Software Foundation" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    nor may "Apache" appear in their name, without prior written
 *    permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */
package org.apache.cocoon.generation;

import org.apache.avalon.framework.parameters.Parameterizable;
import org.apache.avalon.framework.parameters.Parameters;
import org.apache.avalon.framework.parameters.ParameterException;
import org.apache.cocoon.Constants;
import org.apache.cocoon.ProcessingException;
import org.apache.cocoon.environment.ObjectModelHelper;
import org.apache.cocoon.environment.Request;
import org.apache.cocoon.environment.SourceResolver;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;

import java.io.IOException;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.Map;

/**
 * Generates an XML representation of the incoming request.
 * <p>
 * <b>Configuration options:</b>
 * <dl>
 * <dt> <i>container-encoding</i> (optional)
 * <dd> The encoding used by container. Default value is ISO-8859-1.
 * <dt> <i>form-encoding</i> (optional)
 * <dd> The supposed encoding of the request parameter. Default is null.
 * </dl>
 * These configuration options supported in both declaration and use time.
 *
 * @author <a href="mailto:fumagalli@exoffice.com">Pierpaolo Fumagalli</a>
 *         (Apache Software Foundation, Exoffice Technologies)
 * @author <a href="mailto:Giacomo.Pati@pwr.ch">Giacomo Pati</a>
 * @author <a href="mailto:vgritsenko@apache.org">Vadim Gritsenko</a>
 * @author <a href="mailto:kevin.ross@bredex.com">Kevin Ross</a>
 * @version CVS $Id: RequestGenerator.java,v 1.5 2002/02/07 08:17:52 cziegeler Exp $
 */
public abstract class AbstractRequestGenerator extends ServletGenerator implements Parameterizable {

    /** The URI of the namespace of this generator. */
    private String namespaceURI;
    private String headerListElementName;
    private String parameterListElementName;
    private String global_container_encoding;
    private String global_form_encoding;
    private String container_encoding;
    private String form_encoding;

    protected String getNamespaceURI(){
    
        return this.namespaceURI;
    }
    
    protected void setNamespaceURI(String namespaceURI){
     
        this.namespaceURI = namespaceURI;
    }
    
    protected void setHeaderListElementName(String headerListElementName){
        
        this.headerListElementName = headerListElementName;
    }
    
    protected String getHeaderListElementName(){
     
        return this.headerListElementName;
    }
    
    protected void setParameterListElementName(String parameterListElementName){
        
        this.parameterListElementName = parameterListElementName;
    }
    
    protected String getParameterListElementName(){
     
        return this.parameterListElementName;
    }    
    
    public void parameterize(Parameters parameters)
    throws ParameterException {
        // super.parameterize(parameters);

        global_container_encoding = parameters.getParameter("container-encoding", "ISO-8859-1");
        global_form_encoding = parameters.getParameter("form-encoding", null);
    }

    public void setup(SourceResolver resolver, Map objectModel, String src, Parameters par)
    throws ProcessingException, SAXException, IOException {
        super.setup(resolver, objectModel, src, par);

        container_encoding = par.getParameter("container-encoding", global_container_encoding);
        form_encoding = par.getParameter("form-encoding", global_form_encoding);
    }

    /**
     * Generate XML data.
     */
    public void generate()
    throws SAXException {
        Request request = ObjectModelHelper.getRequest(objectModel);
        this.contentHandler.startDocument();
        this.contentHandler.startPrefixMapping("",getNamespaceURI());
        AttributesImpl attr=new AttributesImpl();

        this.attribute(attr,"target", request.getRequestURI());
        this.attribute(attr,"source", (this.source != null ? this.source : ""));
        this.start("request", attr);
        this.data("\n");
        this.data("\n");

        this.data("  ");
        this.start(getHeaderListElementName(), attr);
        this.data("\n");
        Enumeration headers=request.getHeaderNames();
        while (headers.hasMoreElements()) {
            String header=(String)headers.nextElement();
            this.attribute(attr,"name",header);
            this.data("    ");
            this.start("header",attr);
            this.data(request.getHeader(header));
            this.end("header");
            this.data("\n");
        }
        this.data("  ");
        this.end(getHeaderListElementName());
        this.data("\n");
        this.data("\n");

        this.data("  ");
        this.start(getParameterListElementName(),attr);
        this.data("\n");
        Enumeration parameters=request.getParameterNames();
        while (parameters.hasMoreElements()) {
            String parameter=(String)parameters.nextElement();
            this.attribute(attr,"name",parameter);
            this.data("    ");
            this.start("parameter",attr);
            this.data("\n");
            String values[]=request.getParameterValues(parameter);
            if (values!=null) for (int x=0; x<values.length; x++) {
                this.data("      ");
                this.start("value",attr);
                if (form_encoding != null) {
                    try {
                        this.data(new String(values[x].getBytes(container_encoding),
                            form_encoding));
                    } catch(java.io.UnsupportedEncodingException uee) {
                        throw new RuntimeException("Unsupported Encoding Exception: " +
                            uee.getMessage());
                    }
                } else {
                    this.data(values[x]);
                }
                this.end("value");
                this.data("\n");
            }
            this.data("    ");
            this.end("parameter");
            this.data("\n");
        }
        this.data("  ");
        this.end(getParameterListElementName());
        this.data("\n");
        this.data("\n");

        this.data("  ");
        this.start("configurationParameters",attr);
        this.data("\n");
        String[] confparams=super.parameters.getNames();
        for (int i=0; i<confparams.length; i++) {
            this.attribute(attr, "name", confparams[i]);
            this.data("    ");
            this.start("parameter",attr);
            this.data(super.parameters.getParameter(confparams[i], ""));
            this.end("parameter");
            this.data("\n");
        }
        this.data("  ");
        this.end("configurationParameters");
        this.data("\n");
        this.data("\n");

        this.end("request");

        // Finish
        this.contentHandler.endPrefixMapping("");
        this.contentHandler.endDocument();
    }

    private void attribute(AttributesImpl attr, String name, String value) {
        attr.addAttribute("",name,name,"CDATA",value);
    }

    private void start(String name, AttributesImpl attr)
    throws SAXException {
        super.contentHandler.startElement(getNamespaceURI(),name,name,attr);
        attr.clear();
    }

    private void end(String name)
    throws SAXException {
        super.contentHandler.endElement(getNamespaceURI(),name,name);
    }

    private void data(String data)
    throws SAXException {
        super.contentHandler.characters(data.toCharArray(),0,data.length());
    }
}