/*
 * $Id: FopPrintServlet.java,v 1.2 2003/03/07 09:48:05 jeremias Exp $
 * ============================================================================
 *                    The Apache Software License, Version 1.1
 * ============================================================================
 *
 * Copyright (C) 1999-2003 The Apache Software Foundation. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modifica-
 * tion, 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 "FOP" 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 (INCLU-
 * DING, 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 and was originally created by
 * James Tauber <jtauber@jtauber.com>. For more information on the Apache
 * Software Foundation, please see <http://www.apache.org/>.
 */
package org.apache.fop.servlet;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.List;

import java.awt.print.PrinterJob;
import java.awt.print.PrinterException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.xml.transform.TransformerFactory;

import org.xml.sax.InputSource;

// Avalon
import org.apache.avalon.framework.logger.ConsoleLogger;
import org.apache.avalon.framework.logger.Logger;

// FOP
import org.apache.fop.apps.Session;
import org.apache.fop.apps.FOPException;
import org.apache.fop.area.PageViewport;
import org.apache.fop.apps.XSLTInputHandler;
import org.apache.fop.render.awt.AWTRenderer;

/**
 * Example servlet to generate a fop printout from a servlet.
 * Printing goes to the default printer on host where the servlet executes.
 * Servlet param is:
 * <ul>
 *   <li>fo: the path to a XSL-FO file to render
 * </ul>
 * or
 * <ul>
 *   <li>xml: the path to an XML file to render</li>
 *   <li>xslt: the path to an XSLT file that can transform the above XML to XSL-FO</li>
 * </ul>
 * <br/>
 * Example URL: http://servername/fop/servlet/FopPrintServlet?fo=readme.fo
 * <br/>
 * Example URL: http://servername/fop/servlet/FopPrintServlet?xml=data.xml&xsl=format.xsl
 *
 * @author <a href="mailto:fop-dev@xml.apache.org">Apache XML FOP Development Team</a>
 * @version $Id: FopPrintServlet.java,v 1.2 2003/03/07 09:48:05 jeremias Exp $
 * (todo) Doesn't work since there's no AWTRenderer at the moment. Revisit when
 * available.
 * (todo) Don't use XSLTInputHandler anymore
 * (todo) Ev. add caching mechanism for Templates objects
 */
public class FopPrintServlet extends HttpServlet {

    /** Name of the parameter used for the XSL-FO file */
    protected static final String FO_REQUEST_PARAM = "fo";
    /** Name of the parameter used for the XML file */
    protected static final String XML_REQUEST_PARAM = "xml";
    /** Name of the parameter used for the XSLT file */
    protected static final String XSLT_REQUEST_PARAM = "xslt";

    /** Logger to give to FOP */
    protected Logger log = null;
    /** The TransformerFactory to use to create Transformer instances */
    protected TransformerFactory transFactory = null;

    /**
     * @see javax.servlet.GenericServlet#init()
     */
    public void init() throws ServletException {
        this.log = new ConsoleLogger(ConsoleLogger.LEVEL_WARN);
        this.transFactory = TransformerFactory.newInstance();
    }

    /**
     * @see javax.servlet.http.HttpServlet#doGet(HttpServletRequest, HttpServletResponse)
     */
    public void doGet(HttpServletRequest request,
                      HttpServletResponse response) throws ServletException {
        if (log == null) {
            log = new ConsoleLogger(ConsoleLogger.LEVEL_WARN);
        }

        try {
            String foParam = request.getParameter(FO_REQUEST_PARAM);
            String xmlParam = request.getParameter(XML_REQUEST_PARAM);
            String xsltParam = request.getParameter(XSLT_REQUEST_PARAM);

            if (foParam != null) {
                InputStream file = new java.io.FileInputStream(foParam);
                renderFO(new InputSource(file), response);
            } else if ((xmlParam != null) && (xsltParam != null)) {
                XSLTInputHandler input =
                  new XSLTInputHandler(new File(xmlParam),
                                       new File(xsltParam));
                renderXML(input, response);
            } else {
                response.setContentType("text/html");

                PrintWriter out = response.getWriter();
                out.println("<html><title>Error</title>\n"
                        + "<body><h1>FopServlet Error</h1>\n"
                        + "<h3>No 'fo' or 'xml/xsl' "
                        + "request param given.</h3></body>\n</html>");
            }
        } catch (ServletException ex) {
            throw ex;
        } catch (Exception ex) {
            throw new ServletException(ex);
        }
    }

    /**
     * Renders an FO inputsource to the default printer.
     * @param foFile The XSL-FO file
     * @param response Response to write to
     * @throws ServletException In case of a problem
     */
    public void renderFO(InputSource foFile,
                         HttpServletResponse response) throws ServletException {
        try {
            Session session = new Session(foFile, null);
            PrinterJob pj = PrinterJob.getPrinterJob();
            PrintRenderer renderer = new PrintRenderer(pj);

            session.enableLogging(log);
            session.setRenderer(renderer);
            session.run();

            reportOK (response);
        } catch (Exception ex) {
            throw new ServletException(ex);
        }
    }

    /**
     * Renders an FO generated using an XML and a stylesheet to the default printer.
     * @param input XSLTInputHandler to use
     * @param response Response to write to
     * @throws ServletException In case of a problem
     */
    public void renderXML(XSLTInputHandler input,
                          HttpServletResponse response) throws ServletException {
        try {
            Session session = new Session();
            PrinterJob pj = PrinterJob.getPrinterJob();
            PrintRenderer renderer = new PrintRenderer(pj);

            pj.setCopies(1);

            session.enableLogging(log);
            session.setRenderer(renderer);
            session.render(input.getParser(), input.getInputSource());

            reportOK (response);
        } catch (Exception ex) {
            throw new ServletException(ex);
        }
    }

    // private helper, tell (browser) user that file printed
    private void reportOK(HttpServletResponse response)
                throws ServletException {
        String sMsg = "<html><title>Success</title>\n"
                + "<body><h1>FopPrintServlet: </h1>"
                + "<h3>The requested data was printed</h3></body></html>";

        response.setContentType("text/html");
        response.setContentLength(sMsg.length());

        try {
            PrintWriter out = response.getWriter();
            out.println(sMsg);
            out.flush();
        } catch (Exception ex) {
            throw new ServletException(ex);
        }
    }

    // This is stolen from PrintStarter
    class PrintRenderer extends AWTRenderer {

        private static final int EVEN_AND_ALL = 0;
        private static final int EVEN = 1;
        private static final int ODD = 2;

        private int startNumber;
        private int endNumber;
        private int mode = EVEN_AND_ALL;
        private int copies = 1;
        private PrinterJob printerJob;

        PrintRenderer(PrinterJob printerJob) {
            super(null);

            this.printerJob = printerJob;
            startNumber = 0 ;
            endNumber = -1;

            printerJob.setPageable(this);

            mode = EVEN_AND_ALL;
            String str = System.getProperty("even");
            if (str != null) {
                mode = Boolean.valueOf(str).booleanValue() ? EVEN : ODD;
            }
        }

        public void stopRenderer() throws IOException {
            super.stopRenderer();

            if (endNumber == -1) {
                endNumber = getPageCount();
            }

            List numbers = getInvalidPageNumbers();
            for (int i = numbers.size() - 1; i > -1; i--) {
                //removePage(
                //  Integer.parseInt((String) numbers.elementAt(i)));
            }

            try {
                printerJob.print();
            } catch (PrinterException e) {
                e.printStackTrace();
                throw new IOException("Unable to print: "
                                    + e.getClass().getName() + ": " + e.getMessage());
            }
        }

        public void renderPage(PageViewport page) throws IOException, FOPException {
            pageWidth = (int)((float) page.getViewArea().getWidth() / 1000f);
            pageHeight = (int)((float) page.getViewArea().getHeight() / 1000f);
            super.renderPage(page);
        }


        private List getInvalidPageNumbers() {

            List list = new java.util.ArrayList();
            int max = getPageCount();
            boolean isValid;
            for (int i = 0; i < max; i++) {
                isValid = true;
                if (i < startNumber || i > endNumber) {
                    isValid = false;
                } else if (mode != EVEN_AND_ALL) {
                    if (mode == EVEN && ((i + 1) % 2 != 0)) {
                        isValid = false;
                    } else if (mode == ODD && ((i + 1) % 2 != 1)) {
                        isValid = false;
                    }
                }

                if (!isValid) {
                    list.add(Integer.toString(i));
                }
            }

            return list;
        }
    } // class PrintRenderer

}